h jo Water Resources Data Puerto Rico and the U.S. Virgin Islands Water Year 1991 St Thomas 1 Isia ;!a de tP Culebra Isia de Vieques PUERTO RICO St John I U. S. V I R G I N ISLANDS Saint Croix U.S. GEOLOGICAL SURVEY WATER-DATA REPORT PR-91-1 Prepared in cooperation with the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands, and other agencies CALENDAR FOR WATER YEAR 1991 1990 OCTOBER S M T W T F S 123456 7 8. 9 10 11 12 13 14 15 16 1718 19 20 21 22 23 24 25 26 27 28 29 30 31 NOVEMBER S M T W T F S 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 DECEMBER S M T W T F S 1 2345678 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1991 JANUARY S M T W T F S FEBRUARY S M T W T F S MARCH S M T W T F S 12345 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 APRIL S M T W T F S 123456 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 JULY S M T W T F S 123456 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1 2 3456789 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 MAY S M T W T F S 1234 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 .27 28 29 30 31 AUGUST S M T W T F S 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1 2 5456789 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 JUNE S M T W T F S 1 2345678 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 SEPTEMBER S M T W T F S 1234567 8 9 10 11 12 13 14' 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Water Resources Data Puerto Rico and the U.S. Virgin Islands Water Year 1991 by R.E. Curtis, Jr., Z. Aquino, P.L. Diaz, and R.J. Vachier St Thomas Isiaia de v^ Culebra Isia de Vieques PUERTO RICO St John I U. S. V I R G I N ISLANDS Saint Croix I U.S. GEOLOGICAL SURVEY WATER-DATA REPORT PR-91-1 Prepared in cooperation with the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands, and other agencies U.S. DEPARTMENT OF THE INTERIOR MANUEL LUJAN, JR., Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director For additional information on the water resources investigation programs in Puerto Rico and the U.S. Virgin Islands write to: Chief, Caribbean District, Water Resources Division U.S. Geological Survey P.O. Box 364424 San Juan, Puerto Rico 00936-4424 (Telephone: (809) 749-4346) Ml PREFACE This annual hydrologic data report of Puerto Rico and the U.S. Virgin Islands is one of a series of annual reports that document hydrologic data gathered from the U.S. Geological Survey's surface- and ground-water data-collection networks in each state, Puerto Rico, the U.S. Virgin Islands, and the other Trust Territories. These records of streamflow, ground-water levels, and quality of water provide the hydrologic information needed by state, local and Federal agencies, and the private sector for developing and managing our Nation's land and water resources. The report is the culmination of a concerted effort by dedicated personnel of the U.S. Geological Survey, Water Resources Division who collected, compiled, analyzed, verified, and organized the data, and who typed, edited, and assembled the report In addition to the authors, who had primary responsibility for assuring that the information contained herein is accurate, complete and adheres to Geological Survey policy and established guidelines, the following personnel contributed significantly to the collection, processing and tabulations of the data: Jos6 M. Agis Carlos Narvaez George Arroyo Keith Overton Angel Class-Cacho David Payton Iris M. Concepcidn Rafael Pena-Cortez Angel G. Ferrer Francisco Perez-Blair Carlos Figueroa Ronald Richards Eduardo Figueroa Julio A. Rodriguez Pedro Galindo Miguel Rodriguez Alien Gellis Carlos C. Rodriguez Jos6 Gonzalez Ana V. Sanchez Evelyn S. Guevara Jos£ Ren6 Sanchez Sen£n Guzman-Rios Luis Santiago-Rivera Alien Heaken Carlos S antes Felipe Hernandez Luis Soler Richard Kessler Heriberto Torres-Sierra Sandra Lagares Jos£ A. Torres Xevier Maldonado Michael Torres Ernesto Mangual Ahmed Valencia Ruth I. Guzman typed the text of the report. Rafael Medina prepared the illustrations. This report was prepared in cooperation with agencies of the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands, and with other federal agencies under the general supervision of Alien L. Zack, District Chief, Caribbean District, San Juan, Puerto Rico. 5O3T?-1flt REPORT DOCUMENTATION PAGE 1. REPORT NO. USGS/WRD/HD-92/267 3. Recipient's Accession No. 4. Title and Subtitl* Water Resources Data for Puerto Rico and the U.S. Virgin Islands Water Year 1991 5. Report Data March 1992 7. Author oq IO Z coO 0< > CO JJ; o oq to 2, go 0< o B > > Z c_ C O l to WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 Table 3. Surface-water quality stations in Puerto Rico with highest concentration of selected constituents during the 1991 water year [All constituent concentrations are in milligrams per liter; MBAS, Methylene blue active substance] Station number 50129700 50129700 50057025 50055400 50055250 50048800 50138000 50048800 Station name Rio Loco at Guanica Rio Loco at Guanica Rio Gurabo near Gurabo Rio Bairoa near Caguas Rio Caguitas at Highway 30 at Caguas Rio Piedras near Rio Piedras Rio Guanaj ibo near Hormigueros Rio Piedras near Rio Piedras Constituent Sulfide Boron Manganese Iron Zinc Cyanide Phenols MBAS Concent rat ion 0 1 0 13 0 0 0 1 .6 .0 .61 .050 .020 .013 .1 Table 4. Maximum suspended-sediment concentrations and loads during the 1991 water-year Station name Station number Maximum suspended- Maximum suspended- sediment concentration sediment load (milligrams per liter) (tons per day) Rio Tanamci near Utuado Rio de La Plata at Comerlo Rio Piedras at El Senorial Rio Piedras at Rio Piedras Quebrada Blanca at El Jagual 50028000 50043800 50048770 50049000 50051150 1,900 1,300 3,920 2,470 255 16,500 22,600 8,310 7,730 277 Quebrada Salva- tierra near San Lorenzo Rio Grande de Lolza at Caguas Rio Gurabo below El Mang6 Rio Valenciano near Juncos Rio Gurabo at Gurabo Rio Canas at Rio Canas Rio Grande de Lolza below Damsite Rio Toa Vaca above Lago Toa Vaca Rio Rosario near Hormigueros 50051180 50055000 50055750 50056400 50057000 50058350 50059050 50110900 50136400 669 1,650 1,000 555 1,080 1,430 274 2,510 1,150 273 25,500 5,100 1,960 9,200 4,920 4,920 6,340 4,420 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 SPECIAL NETWORKS AND PROGRAMS National Stream Quality Accounting Network (NASQAN) is a nationwide data-collection network designed by the U.S. Geological Survey to meet many of the information needs of government agencies and other groups involved in natural or regional water-quality planning and management The 500 or so sites on NASQAN are generally located at the downstream ends of hydrologic accounting units designated by the U.S. Geological Survey Office of Water Data Coordination in consultation with the Water Resources Council. The objectives of NASQAN are (1) to obtain information on the quality and quantity of water moving within and from the United States through a systematic and uniform process of data collection, summarization, analysis, and reporting such that the data may be used for, (2) description of the area! variability of water quality in the Nation's rivers through analysis of data from this and other programs, (3) detection of changes or trends with time in the pattern of occurrence of water-quality characteristics, and (4) providing a nationally consistent data base useful for water-quality assessment and hydrologic research. EXPLANATION OF RECORDS The surface-water and ground-water records published in this report are for the 1991 water year that began October 1, 1990 and ended September 30, 1991. A calendar of the water year is provided on the inside of the front cover. The records contain streamflow data, water-quality data for surface and ground water, and ground-water-level data. The locations of the stations and wells where the data were collected are shown in figures 3 to 10. The following sections of the introductory text are presented to provide users with a more detailed explanation of how the hydrologic data published in this report were collected, analyzed, computed, and arranged for presentation. Station Identification Numbers Each data station, whether streamsite or well, in this report is assigned a unique identification number. This number is unique in that it applies specifically to a given station and to no other. The number usually is assigned when a station is first established and is retained for that station indefinitely. The systems used by the U.S. Geological Survey to assign identification numbers for surface-water stations and for ground-water well sites differ, but both are based on geographic location. The "downstream order" system is used for regular surface-water stations and the "latitude- longitude" system is used for wells. Downstream Order System Since October 1, 1950, the order of listing hydrologic-station records in Survey reports is in a downstream direction along the main stream. All stations on a tributary entering upstream from a main-stream station are listed before that station. A station on a tributary that enters between two main-stream stations is listed between them. A similar order is followed in listing stations in first rank, second rank, and other ranks of tributaries. As an added means of identification, each hydrologic station and partial-record station has been assigned a station number. These are in the same downstream order used in this report. In assigning station numbers, no distinction is made between partial-record stations and other stations; therefore, the station number for a partial-record station indicates downstream order position in a list made up of both types of stations that may be established; hence, the numbers are not consecutive. The complete 8-digit number for each station such as 50028000, which appears just to the left of the station name, includes the 2-digit part number "50" plus the 6-digit downstream order number "028000." Latitude-Longitude System The 8-digit downstream order station numbers are not assigned to wells and miscellaneous sites where only random water-quality samples or discharge measurements are taken. The well and miscellaneous site numbering system of the U.S. Geological Survey is based on the grid system of latitude and longitude. The system provides the geographic location of the well or miscellaneous site and a unique number for each site. The number consists of 15 digits. The first 6 digits denote the degrees, minutes, and seconds of latitude, the next 7 digits denote degrees, minutes, and seconds of longitude, and the last 2 digits (assigned sequentially) identify the wells or other sites within a 1-second grid. The numbers shown in the grid correspond to the local numbers assigned to each well as visited in the field. An example is well 16 (fig.ll). 87*15! 45' 3D' 15' 88*00! 65*30' 18"30' IS1 18*00' 0 0 , 10 20 s 3 10 <»ys v*« KILOMETERS 20 MILES EXPLANATION FECAL STREPTOCOCCI • < 1000 • 1000-10,000 • 10,000-100,000 | 100,000-1,000,000 • > 1,000,000 Figure 3.--Location of fecal coliform bacteria concentration at sampled sites. 45' 30' 15 s 45' 65*30' 18*30' i" .^ flfo CuM»in»s fflp Ou»ifnbo X^A i rtraruto -^*"C ^ 15' 10 20 10 ^7^^ 30 \V~ S^1^ X"S ^ .« ( W8 EXPLANATION FECAL STREPTOCOCCI < 1000 1000-10,000 10,000-100,000 100,000-1,000,000 Figure 4.--Location of fecal streptococci bacteria concentration at sampled sites. 10 67*00' 15' 8S'30 ! 18"30! Wo CWtotvmais,, Sfe G«fS>*js fl/0 OrtsnsMf^ J"*' ^""s 11478 >v. \ Sfc ¥&$&&*! fid QuattttfboA .1380 A-'' ,ex ^ }£^-~-4£ io381 te^i ~.0395 ) A 7^mo A ^^ \ V k 1 {o^'^woy (Y *-^t-^ e ^ /AA0638 .143 / k V0350 S^S B0450 \ r* iT50^ ^/A^ S >o Jj£^\ . £ 031 2))/) > ! "oa» / V *T^ x A ^.,^ Tv^JW ;jfLj./^jLjJX ^ ^ n^AV |(V^ r/^.^X. V A/«^||' "81% AA^» U /1-\ S \ /"\ ") ) / 025155 " ( B 03?90 IfVTV 0438Y'7 ^"X ^^yosfe ^ ^056* V J V\ N A\'U_-\ | V/Kr.04 f^\ <-«^fiL)^r-'X>^ >W ^\ -^x ^ V-=^ "^/Y'"""* /^ J V \ > 05302S /-v^psoi ^—-J Vj fitoA-MirtHwr i«JL\\. 1 °°2A 039^1 .^^ j \V ^*——— /0148 ^ «^v* ^ .^j *^* .^u / -yK'/^'l X" .,'•> «^ S * V-\fo« , yOi H ji /AA0*38 (^f-fS^y 032290^8 ' 11^A! Ii25 A / i24aA «A VA:.1115 )_ 10 10 $ "> V^ 30 Ji 20 EXPLANATION A 0920 CONTINOUS STREAMFLOW ~ STATION AND NUMBER A 1006 CREST STAGE GAGE • 1415 LAKE-ELEVATION STATION Figure 5.--Location of surface-water stations in Puerto Rico. 67*15! B?"00' 46' <$ s$P /(«• ^ XV Ja v» ^r^_—i# ,-** f- —— \! * EXPLANATION QUALITY OF WATER STATIONS ** SC *- — \j> ^0430 BIOLOGICAL CHEMICAL (Dai'y) SED |MENT (Bi-monthly) Figure 6.--Location of water-quality stations in Puerto Rico. 18 S30! 87 S 15 ! p"~| 18*00' EXPLANATION A LOW-FLOW PARTIAL-RECORD STATION 1107 STATION IDENTIFICATION NUMBER 146075A Rfo Grande^ \ 1109 I . y ,AJ A0" A - s 30 Figure 7.-Location of low-flow partial-record stations in southwest Puerto Rico. 65*30' EXPLANATION e WELL AND WELL NUMBER 18*00' " Figure 8.-Location of ground-water stations in Puerto Rico. Ol 16 ^s^<*^i s^s 85 05 ST. *x. Cha I Amalii 01234 ..™ _ 01234 234 3,4 01234 01234 Figure 9.--Location of surface-water stations in the U.S. Virgin Islands. 17 CC 6f|C» WsJ WiJ V ^S~\ Xw**-^-" 01234 •N*/^4 ^~\ 1 6 "*L* 5 TJ {'- ^ I i I I i 01234 ««,., ^C/^ ST. ^2*97 14«'\ B" ^r^ 10 - 11 •/ 13 01234 0 1 2 3 , 4 MIL! 'X, 64S50S 45' 40 s 64*35* 1?845* 17*40* ST. 01234 Kii 01234 Figure 10.-Location of ground-water stations in the U.S. Virgin Islands. 18 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 66°53' 52' 51' 50' 49' 48' 66°47' 18° 02' — or loOnn' 1 7 Oca' 134 132^ 131* \ X.'6 jr •27 •74 C< X" c COORDINATES FOR WELLS 27 (180150066474900) AND 74 (180135066471000) COORDINATES FOR WELLS 132 (180133066503300) AND 134 (180120066503200) COORDINATES FOR WELL 131 (180058066502700) COORDINATES FOR WELL 16 (175922066495800) Figure 11.--Grid showing system for numbering wells and miscellaneous sites (latitude and longitude). Records of Stage and Water Discharge Records of stage and water discharge may be complete or partial. Complete records of discharge are those obtained using a continuous stage-recording device through which either instantaneous or mean daily discharges may be computed for any time, or any period of time, during the period of record. Complete records of lake or reservoir content, similarly, are those for which stage or content may be computed or estimated with reasonable accuracy for any time, or period of time. They may be obtained using a continuous stage-recording device, but need not be. Because daily mean discharges and end-of-day contents commonly are published for such stations, they are referred to as "daily stations." By contrast, partial records are obtained through discrete measurements without using a continuous stage-recording device and pertain only to a few flow characteristics, or perhaps only one. 'The nature of the partial record is indicated by table titles such as "Crest-stage partial records," or "Low-flow partial records." Records of miscellaneous discharge measurements or of measurements from special studies, such as low-flow seepage studies, may be considered as partial records, but they are presented separately in this type of report. Location of all complete-record and crest-stage partial- record stations for which data are given in this report are shown in figures 5 and 8. Data Collection and Computation The data obtained at a complete-record gaging station on a stream or canal consists of a continuous record of stage, individual measurements of discharge throughout a range of stages, and notations regarding factors that may affect the relationships between stage and discharge. These data, together with supplemental information, such as weather records, are used to compute daily discharges. The data obtained at a complete-record gaging station on a lake or reservoir consist of a record of stage and of notations regarding factors that may affect the relationship between stage and lake content These data are used with stage-area and stage-capacity curves or tables to compute water-surface areas and lake storage. Continuous records of stage are obtained with analog recorders that trace continuous graphs of stage or with digital recorders that punch stage values on paper tapes at selected time intervals or electronic satellite data collector platforms that receive stage values at selected time intervals. Measurements of discharge are made with current meters using methods adapted by the Geological Survey as a result of experience accumulated since 1880. These methods are described in standard textbooks, in Water-Supply Paper 2175, and in U.S. Geological Survey Techniques of Water- Resources Investigations, Book 3, Chapter A6. 19 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 In computing discharge records, results of individual measurements are plotted against the corresponding stages, and stage-discharge relation curves are then constructed. From these curves, rating tables indicating the approximate discharge for any stage within the range of the measurements are prepared. If it is necessary to define extremes of discharge outside the range of the current-meter measurements, the curves are extended using: (1) logarithmic plotting; (2) velocity-area studies; (3) results of indirect measurements of peak discharge, such as slope-area or contracted-opening measurements, and computations of flow-over-dams or weirs; or (4) step-backwater techniques. Daily mean discharges are computed by applying the daily mean stages (gage heights) to the stage-discharge curves or tables. If the stage-discharge relation is subject to change because of frequent or continual change in the physical features that form the control, the daily mean discharge is determined by the shifting-control method, in which correction factors based on the individual discharge measurements and notes of the personnel making the measurements are applied to the gage heights before the discharges are determined from the curves or tables. This shifting-control method also is used if the stage-discharge relation is changed temporarily because of aquatic growth or debris on the control. At some stream-gaging stations the stage-discharge relation is affected by the backwater from reservoirs, tributary streams, or other sources. This necessitates the use of the slope method in which the slope or fall in a reach of the stream is a factor in computing discharge. The slope or fall is obtained by means of an auxiliary gage set at some distance from the base gage. At some stations the stage-discharge relation is affected by changing stage; at these stations the rate of change in stage is used as a factor in computing discharge. In computing records of lake or reservoir contents, it is necessary to have available from surveys, curves or tables defining the relationship of stage and contents. The application of stage to the stage-content curves or tables gives the contents from which daily, monthly or yearly changes then are determined. If the stage-content relationship changes because of deposition of sediment in a lake or reservoir, periodic surveys may be necessary to redefine it Even when this is done, as time between the last survey increases, the contents computed may increase in error. Discharges over lake or reservoir spillways are computed from stage-discharge relationships much as other stream discharges are computed. For some gaging stations there are periods when no gage-height record is obtained, or the recorded gage height is so faulty that it cannot be used to compute daily discharge or contents. This happens when the recorder stops or otherwise fails to operate properly, intakes are plugged, the float is loose in the well, or for various other reasons. For such periods, the daily discharges are estimated from the recorded range in stage, previous or following record, discharge measurements, weather records, and comparison with other station records from the same or nearby basins. Likewise, daily contents may be estimated from operator's logs, previous or following record, inflow-outflow studies, and other information. Information explaining how estimated daily-discharge values are identified in station records is included in the next two sections, "Data Presentation" (REMARKS paragraph) and "Identifying Estimated Daily Discharge." Data Presentation The records published for each gaging station consist of two parts, the manuscript or station description and the data table for the current water year. The manuscript provides, under various headings, descriptive information, such as station location; period of record; average discharge; historical extremes; record accuracy; and other remarks pertinent to station operation and regulation. The following information, as appropriate, is provided with each continuous record of discharge or lake content Comments to follow clarify information presented under the various headings of the station description. LOCATION.-Information on locations is obtained from the most accurate maps available. The location of the gage with respect to the cultural and physical features in the vicinity and with respect to the reference place mentioned in the station name is given. DRAINAGE AREA.—Drainage areas are measured using the most accurate maps available. Drainage areas are updated as better maps become available. PERIOD OF RECORD.-This indicates the period for which there are published records for the station or for an equivalent station. An equivalent station is one that was in operation at a time that the present station was not, and whose location was such that records from it can reasonable be considered equivalent with records from the present station. 20 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 REVISED RECORDS.-Published records, because of new information, occasionally are found to be incorrect, and revisions are printed in later reports. Listed under this heading are all the reports in which revisions have been published for the station and the water years to which the revisions apply. If a revision did not include daily, monthly, or annual figures of discharge, that fact is noted after the year dates as follows: "(M)" means that only the instantaneous maximum discharge was revised; "(m)" that only the instantaneous minimum was revised; and "(P)" that only peak discharges were revised. If the drainage area has been revised, the report in which the most recently revised figure was first published is given. GAGE.-The type of gage in current use, the datum of the current gage, and a condensed history of the types, locations, and datums of previous gages are given under this heading. REMARKS.--A11 periods of estimated daily-discharge record will either be identified by date in this paragraph of the station description for water-discharge stations or flagged in the daily-discharge table. (See next section, "Identifying Estimated Daily Discharge.") If a remarks statement is used to identify estimated record, the paragraph will begin with this information presented as the first entry. The paragraph is also used to present information relative to the accuracy of the records, to special methods of computations, to conditions that affect natural flow at the station and, possibly, to other pertinent items. For reservoir stations, information is given on the dam forming the reservoir, the capacity, outlet works and spillway, and purpose and use of the reservoir. COOPERATION.--Records provided by a cooperating organization or obtained for the Geological Survey by a cooperating organization are identified here. AVERAGE DISCHARGE.—The discharge value given is the arithmetic mean of the water-year mean discharges. It is computed only for stations having at least 5 water years of complete record, and only water years of complete record are included in the computation. It is not computed for stations where diversions, storage, or other water-use practices cause the value to be meaningless. If water developments significantly altering flow at a station are put into use after the station has been in operation for a period of years, a new average is computed as soon as 5 water years of record have accumulated following the development The median of yearly mean discharges also is given under this heading for stations having 10 or more water years of record, if the median differs from the average given by more than 10 percent. EXTREMES FOR PERIOD OF RECORD.~Extremes may include maximum and minimum stages and maximum and minimum discharges or content Unless otherwise qualified, the maximum discharge or content is the instantaneous maximum corresponding to the highest stage that occurred. The highest stage may have been obtained from a graphic or digital recorder, a crest-stage gage, or by direct observation of a nonrecording gage. If the maximum stage did not occur on the same day as the maximum discharge or content it is given separately. Similarly, the minimum is the instantaneous minimum discharge, unless otherwise qualified, and was determined and is reported in the same manner as the maximum. EXTREMES OUTSIDE PERIOD OF RECORD.-Included here is information concerning major floods or unusually low flows that occurred outside the stated period of record. The information may or may not have been obtained by the U.S. Geological Survey. EXTREMES FOR CURRENT YEAR.-Extremes given here are similar to those for the period of record, except the peak discharge listing may include secondary peaks. For stations meeting certain criteria, all peak discharges and stages occurring during the water year and greater than a selected base discharge are presented under this heading. The peaks greater than the base discharge, excluding the highest one, are referred to as secondary peaks. Peak discharges are not published for canals, ditches, drains, or streams for which the peaks are subject to substantial control by man. The time of occurrence for peaks is expressed in 24-hour local standard time. For example, 12:30 a.m. is 0030, and 1:30 p.m. is 1330. The minimum for the current water year appears below the table of peak data. REVISIONS.—If a critical error in published records is discovered, a revision is included in the first report published following discovery of the error. 21 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 Although rare, occasionally the records of a discontinued gaging station may need revision. Because, for these stations, there would be no current or, possibly, future station manuscript published to document the revision in a "Revised Records" entry, users of data for these stations who obtained the record from previously published data reports may wish to contact the District office to determine if the published records were ever revised after the station was discontinued. Of course, if the data were obtained by computer retrieval, the data would be current and there would be no need to check because any published revision of data is always accompanied by revision of the corresponding data in computer storage. Manuscript information for lake or reservoir stations differs from that for stream stations in the nature of the "Remarks" and in the inclusion of a skeleton stage-capacity table when daily contents are given. The daily table for stream-gaging stations gives mean discharge for each day and is followed by monthly and yearly summaries. In the monthly summary below the daily table, the line headed "TOTAL" gives the sum of the daily figures. The line headed "MEAN" gives the average flow in cubic feet per second during the month. The lines headed "MAX" and "MIN" give the maximum and minimum daily discharges, respectively, for the month. Discharge for the month also is usually expressed in cubic feet per second per square mile (line headed "CFSM"), or in inches (line headed "IN"), or in acre-feet (line headed "AC-FT"). Figures for cubic feet per second per square mile and runoff in inches are omitted if there is extensive regulations or diversion or if the drainage area includes large noncontributing areas. In the yearly summary below the monthly summary, the figures shown are the appropriate discharges for the calendar and water years. Data collected at partial-record stations follow the information for continuous-record sites. Data for partial-record discharge stations are presented in two tables. The first is a table of annual maximum stage and discharge at crest-stage stations, and the second is a table of discharge measurements at low-flow partial-record stations. Identifying Estimated Daily Discharge Estimated daily-discharge values published in the water-discharge tables are identified by flagging individual daily values with the letter symbol "e" and printing a table footnote, "e Estimated." Accuracy of the Records The accuracy of streamflow records depends primarily on: (1) The stability of the stage-discharge relation or, if the control is unstable, the frequency of discharge measurements; and (2) the accuracy of measurements of stage, measurements of discharge, and interpretation of records. The accuracy attributed to the records is indicated under "REMARKS." "Excellent" means that about 95 percent of the daily discharges are within 5 percent of the true; "good," within 10 percent; and "fair," within 15 percent Records that do not meet the criteria mentioned, are rated "poor." Different accuracies may be attributed to different parts of a given record. Daily mean discharges in this report are given to the nearest hundredth of a cubic foot per second for values Jess than 1 ftVs; to the nearest tenth between 1.0 and 10 ftVs; to whole numbers between 10 and 1,000 ft3/s; and to 3 significant figures for more than 1,000 ft3/s. The number of significant figures used is based solely on the magnitude of the discharge value. The same rounding rules apply to discharges listed for partial-record stations and miscellaneous sites. Information used in the preparation of the records in this publication, such as discharge-measurement notes, gage- height records, temperature measurements, and rating tables are on file in the Caribbean District office. Also, most of the daily mean discharges are in computer-readable form and have been analyzed statistically. Information on the availability of the unpublished information or on the results of statistical analyses of the published records may be obtained from the District office. Records of Surface-Water Quality Records of surface-water quality ordinarily are obtained at or near stream-gaging stations because interpretation of records of surface-water quality nearly always requires corresponding discharge data. Records of surface-water quality in this report may involve a variety of types of data and measurement frequencies. 22 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 Classification of Records Water-quality data for surface-water sites are grouped into one of three classifications. A continuing-record station is a site where data are collected on a regularly scheduled basis. Frequency may be once or more times daily, weekly, monthly, or quarterly. A partial-record station is a site where limited water-quality data are collected systematically over a period of years. Frequency of sampling is usually less than quarterly. A miscellaneous sampling site is a location other than a continuing or partial-record station, where random samples are collected to give better area! coverage to define water-quality conditions in the river basin. A careful distinction needs to be made between "continuing records" as used in this report and "continuous recordings," which refers to a continuous graph or a series of discrete values punched at short intervals on a paper tape. Some records of water quality, such as temperature and specific conductance, may be obtained through continuous recordings; however, because of costs, most data are obtained only monthly or less frequently. Locations of stations for which records on the quality of surface water appear in this report are shown in figure 6. Arrangement of Records Water-quality records collected at a surface-water daily record station are published immediately following that record, regardless of the frequency of sample collection. Station number and name are the same for both records. Where a surface-water daily record station is not available or where the water quality differs significantly from that at the nearby surface-water station, the continuing water-quality record is published with its own station number and name in the regular downstream-order sequence. Water-quality data for partial-record stations and for miscellaneous sampling sites appear in separate tables following the table of discharge measurement at miscellaneous sites. On-site Measurements and Sample Collection In obtaining water-quality data, a major concern needs to be assuring that the data obtained represent the in situ quality of the water. To assure this, certain measurements, such as water temperature, pH, and dissolved oxygen, need to be made onsite when the samples are taken. To assure that measurements made in the laboratory also represent the in situ water, carefully prescribed procedures need to be followed in collecting the samples, in treating the samples to prevent changes in quality pending analysis, and in shipping the samples to the laboratory. Procedures for onsite measurements and for collecting, treating, and shipping samples are given in publications on 'Techniques of Water- Resources Investigations," Book 1, Chap. D2; Book 3, Chap. C2; Book 5, Chap. Al, A3, and A4. Detailed information on collecting, treating, and shipping samples may be obtained from the Geological Survey District office. One sample can define adequately the water quality at a given time if the mixture of solutes throughout the stream cross section is homogeneous. However, the concentration of solutes at different locations in the cross section may vary widely with different rates of water discharge, depending on the source of material and the turbulence and mixing of the stream. Some streams must be sampled through several vertical sections to obtain a representative sample needed for an accurate mean concentration and for use in calculating load. All samples obtained for the National Stream Quality Accounting Network (see definitions) are obtained from at least several verticals. Whether samples are obtained from the centroid of flow or from several verticals, depends on flow conditions and other factors which must be evaluated by the collector. Chemical-quality data published in this report are considered to be the most representative values available for the stations listed. The values reported represent water-quality conditions at the time of sampling as much as possible, consistent with available sampling techniques and methods of analysis. In the rare case where an apparent inconsistency exists between a reported pH value and the relative abundance of carbon dioxide species (carbonate and bicarbonate), the inconsistency is the result of a slight uptake of carbon dioxide from the air by the sample between measurement of pH in the field and determination of carbonate and bicarbonate in the laboratory. For chemical-quality stations equipped with digital monitors, the records consist of daily maximum, minimum, and mean values for each constituent measured and are based upon hourly punches beginning at 0100 hours and ending at 2400 hours for the day of record. More detailed records, when available, (hourly values) may be obtained from the U.S.G.S. District office whose address is given on the back of the title page of this report. 23 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 Water Temperature Water temperatures are measured at most of the water-quality stations. In addition, water temperatures are taken at time of discharge measurements for water-discharge stations. For stations where water temperatures are taken manually once or twice daily, the water temperatures are taken at about the same time each day. Large streams have a small diurnal temperature change; shallow streams may have a daily range of several degrees and may follow closely the changes in air temperature. Some streams may be affected by waste-heat discharges. At stations where recording instruments are used, either mean temperatures or maximum and minimum temperatures for each day are published. Water temperatures measured at the time of water-discharge measurements are on file in the District office. Sediment Suspended-sediment concentrations are determined from samples collected by using depth-integrating and pumping sediment samplers. Samples usually are obtained at several verticals in the cross section, or a single sample may be obtained at a fixed point and a coefficient applied to determine the mean concentration in the cross sections. During periods of rapidly changing flow or rapidly changing concentration, samples may have been collected more frequently (twice daily or, in some instances, hourly). The published sediment discharges for days of rapidly changing flow or concentration were computed by the subdivided-day method (time-discharge weighted average). Therefore, for those days when the published sediment discharge value differs from the value computed as the product of discharge times mean concentration times 0.0027, the reader can assume that the sediment discharge for that day was computed by the subdivided-day method. For periods when no samples were collected, daily discharges of suspended sediment were estimated on the basis of water discharge, sediment concentrations observed immediately before and after the periods, and suspended-sediment loads for other periods of similar discharge. At other stations, suspended-sediment samples were collected periodically at many verticals in the stream cross section. Although data collected periodically may represent conditions only at the time of observations, such data are useful in establishing seasonal relations between quality and streamflow and in predicting long-term sediment-discharge characteristics of the stream. In addition to the records of suspended-sediment discharge, records of the periodic measurements of the particle- size distribution of the suspended sediment and bed material are included for some stations. Laboratory Measurements Sediment samples, samples for biochemical-oxygen demand (BOD), samples for indicator bacteria, and daily samples for specific conductance are analyzed locally. All other samples are analyzed in the Geological Survey laboratories in Denver, Co. or Ocala, Fla. Methods used in analyzing sediment samples and computing sediment records are given in TWRI, Book 5, Chap. Cl. Methods used by the Geological Survey laboratories are given in TWRI, Book 1, Chap. D2; Book 3, Chap. C2; Book 5, Chap. Al, A3, and A4. Data Presentation For continuing-record stations, information pertinent to the history of station operation is provided in descriptive headings preceding the tabular data. These descriptive headings give details regarding location, drainage area, period of record, type of data available, instrumentation, general remarks, cooperation, and extremes for parameters currently measured daily. Tables of chemical, physical, biological, radiochemical data, and so forth, obtained at a frequency less than daily are presented first, and tables of "daily values" of specific conductance, pH, water temperature, dissolved oxygen, and suspended sediment then follow in sequence, when these parameters are studied. In the descriptive headings, if the location is identical to that of the discharge gaging station, neither the LOCATION nor the DRAINAGE AREA statements are repeated. The following information, as appropriate, is provided with each continuous-record station. Comments that follow clarify information presented under the various headings of the station description. LOCATION.-See Data Presentation under "Records of Stage and Water Discharge;" same comments apply. 24 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 DRAINAGE AREA.-See Data Presentation under "Records of Stage and Water Discharge;" same comments apply. PERIOD OF RECORD.--This indicates the periods for which there are published water-quality records for the station. The periods are shown separately for records of parameters measured daily or continuously and those measured less than daily. For those measured daily or continuously, periods of record are given for the parameters individually. INSTRUMENTATION.-Information on instrumentation is given only if a water-quality monitor temperature record, sediment pumping sampler, or other sampling device is in operation at a station. REMARKS .--Remarks provide added information pertinent to the collection, analysis, or computation of the records. COOPERATION.—Records provided by a cooperating organization or obtained for the Geological Survey by a cooperating organization are identified here. EXTREMES.--Maximums and minimums are given only for parameters measured daily or more frequently. None are given for parameters measured weekly or less frequently, because the true maximums or minimums may not have been sampled. Extremes, when given, are provided for both the period of record and for the current water year. REVISIONS.—If errors in published water-quality records are discovered after publication, appropriate updates are made to the Water-Quality File in the U.S. Geological Survey's computerized data system, WATSTORE, and subsequently by monthly transfer of update transactions to the U.S. Environmental Protection Agency's STORET system. Because the usual volume of updates makes it impractical to document individual changes in the State data-report series or elsewhere, potential users of U.S. Geological Survey water-quality data are encouraged to obtain all required data from the appropriate computer file to insure the most recent updates. The surface-water-quality records for partial-record stations and miscellaneous sampling sites are published in separate tables following the table of discharge measurements at miscellaneous sites. No descriptive statements are given for these records. Each station is published with its own station number and name in the regular downstream-order sequence. Remark Codes The following remark codes may appear with the water-quality data in this report: PRINTED OUTPUT REMARK E Estimated value > Actual value is known to be greater than the value shown < Actual value is known to be less than the value shown K Results based on colony count outside the acceptance range (non-ideal colony count) L Biological organism count less than 0.5 percent (organism may be observed rather than counted) D Biological organism count equal to or greater than IS percent (dominant) & Biological organism estimated as dominant 25 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 Records of Ground-Water Levels Only ground-water level data from a basic network of observation wells are published herein. This basic network contains observation wells so located that the most significant data are obtained from the fewest wells in the most important aquifers. Data Collection and Computation Measurements of water levels are made in many types of wells under varying conditions, but the methods of measurement are standardized to the extent possible. The equipment and measuring techniques used at each observation well ensure that measurements at each well are of consistent accuracy and reliability. Each well is identified by means of (1) a 15-digit number that is based on latitude and longitude and (2) a local number that is provided for local needs. See figure 10. Water-level records are obtained from direct measurements with a steel tape or from the graph or punched tape of a water-stage recorder. The water-level measurements in this report are given in feet with reference to land-surface datum (Isd). Land-surface datum is a datum plane that is approximately at land surface at each well. If known, the elevation of the land-surface datum is given in the well description. The height of the measuring point (MP) above or below land- surface datum is given in each well description. Water levels in wells equipped with recording gages are reported for every day and as an instantaneous observation at noon. Water levels are reported to as many significant figures as can be justified by the local conditions. For example, in a measurement of a depth to water of several hundred feet, the error of determining the absolute value of the total depth to water may be a few tenths of a foot, whereas the error in determining the net change of water level between successive measurements may be only a hundredth of a few hundredths of a foot. For lesser depths to water, the accuracy is greater. Accordingly, most measurements reported to a hundredth of a foot, but some are given to a tenth of a foot or a larger unit. Data Presentation Each well record consists of two parts, the station description and the data table of water levels observed during the water year. The description of the well is presented first through use of descriptive headings preceding the tabular data. The comments to follow clarify information presented under the various headings. LOCATION.—This paragraph follows the well-identification number and reports the latitude and longitude (given in degrees, minutes, and seconds); a landline location designation; the hydrologic-unit number; the distance and direction from a geographic point of reference; and the owner's name. AQUIFER.—This entry designates by name (if a name exists) and geologic age the aquifer(s) open to the well. WELL CHARACTERISTICS .-This entry describes the well in terms of depth, diameter, casing depth and/or screened interval, method of construction, use, and additional information such as casing breaks, collapsed screen, and other changes since construction. DATUM.—This entry describes both the measuring point and the land-surface elevation at the well. The measuring point is described physically (such as top of collar, notch in top of casing, plug in pump base and so on), and in relation to land surface (such as 1.3 ft above land-surface datum). The elevation of the land-surface datum is described in feet above mean sea level datum, if available. It is reported with precision depending on the method of determination. REMARKS.—This entry describes factors that may influence the water level in a well or the measurement of the water level. It should identify wells that also are water-quality observation wells, and may be used to acknowledge the assistance of local (non-survey) observers. PERIOD OF RECORD.-This entry indicates the period for which there are published records for the well. It reports the month and year of the start of publication of water-level records by the U.S. Geological Survey and the words "to current year" if the records are to be continued into the following year. Periods for which water-level records are available, but are not published by the Geological Survey, may be noted. 26 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 EXTREMES FOR PERIOD OF RECORD.--This entry contains the highest and lowest water levels of the period of published record, with respect to land-surface datum, and the dates of their occurrence. A table of water levels follows the station description for each well. Water levels are reported in feet below land- surface datum and all taped measurements of water level are listed. For wells equipped with recorders, daily values tables are published for the instantaneous water-level observation at noon. The highest and lowest water levels of the water year are shown on a line below the table. Because all values are not published for wells with recorders, the extremes may be values that are not listed in the table. Missing records are indicated by dashes in place of the water level. Records of Ground-Water Quality Records of ground-water quality in this type of report differ from other types of records in that for most sampling sites they consist of only one set of measurements for the water year. The quality of ground water ordinarily changes only slowly; therefore, for most general purposes one annual sampling, or only a few samples taken at infrequent intervals during the year, is sufficient Frequent measurement of the same constituents is not necessary unless one is concerned with a particular problem, such as monitoring for trends in nitrate concentration. In the special cases where the quality of ground water may change more rapidly, more frequent measurements are made to identify the nature of the changes. Data Collection and Computation The records of ground-water quality in this report were obtained mostly as a part of special studies in specific areas. Consequently, a number of chemical analyses are presented for some counties but none are presented for others. As a result, the records for this year, by themselves, do not provide a balanced view of ground-water quality Statewide. Such a view can be attained only by considering records for this year in context with similar records obtained for these and other counties in earlier years. Most methods for collecting and analyzing water samples are described in the "U.S. Geological Survey Techniques of Water-Resources Investigations" manuals listed on a following page. The values reported in this type of report represent water-quality conditions at the time of sampling as much as possible, consistent with available sampling techniques and methods of analysis. All samples are obtained by trained personnel. The wells sampled are pumped long enough to assure that the water collected comes directly from the aquifer and has not stood for a long time in the well casing where it would have been exposed to the atmosphere and to the material, possibly metal, comprising the casings. Data Presentation The records of ground-water quality, when available, are published in a section titled QUALITY OF GROUND WATER immediately following the ground-water level records. Data for quality of ground water are listed alphabetically by County, and are identified by well number. The prime identification number for wells sampled is the 15-digit number derived from the latitude-longitude locations. No descriptive statements are given for ground-water-quality records; however, the well number, depth of well, date of sampling, and other pertinent data are given in the table containing the chemical analyses of the ground water. The REMARK codes listed for surface-water-quality records are also applicable to ground-water-quality records. ACCESS TO WATSTORE DATA The U.S. Geological Survey is the principal Federal water-data agency and, as such, collects and disseminates about 70 percent of the water data currently being used by numerous State, local, private, and other Federal agencies to develop and manage our water resources. As part of the U.S. Geological Survey's program of releasing water data to the public, a large-scale computerized system has been developed for the storage and retrieval of water data collected through its activities. The National Water-Data Storage and Retrieval System (WATSTORE) was established in 1972 to provide an effective and efficient means for the processing and maintenance of water data collected through the activities of the U.S. Geological Survey and to facilitate release of the data to the public. A variety of useful products, ranging from data tables to complex statistical analyses such as Log Pearson Type in, can be produced using WATSTORE. The system resides on the central computer facilities of the U.S. Geological Survey at its National Center in Reston, Virginia, and consists of related files and data bases. 27 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 * Station Header File - contains descriptive information on over 440,000 sites throughout the United States and its territories where the U.S. Geological Survey collects or has collected data. * Daily Values Files - Contains over 220 million daily values of streamflow, stages, reservoir contents, water temperatures, specific conductances, sediment concentrations, sediment discharges, and ground-water level. * Pead Flow File - Contains approximately 500,000 maximum (peak) streamflow and gage-height values at surface-water sites. * Water-Quality Data - Contains approximately 2 million analyses of water samples that describe the chemical, physical, biological, and radio-chemicals characteristics of both surface and ground water. * Ground-Water Site Inventory Data Base - Contains inventory data for over 900,000 wells, springs, and other sources of ground water. The data includes site location, geohydrologic characteristics, well-construction history, and one-time field measurements such as water temperature. In 1976, the U.S. Geological Survey opened WATSTORE to the public for direct access. The signing of a Memorandum of Agreement with the Survey is required to obtain direct access to WATSTORE. The system can be accessed either synchronously or asynchronously. The requestor will be expected to pay all computer costs he/she incurs. Direct access may be obtained by contacting: U.S. Geological Survey National Water Data Exchange 421 USGS National Center Reston, Virginia 22092 In addition to provide direct assess to WATSTORE, data can be provided in various machine-readable formats on magnetic tape or 5-1/4 inch floppy disk. Information about the availability of specific types of data or products, and user charges, can be obtained locally from each of the Water Resources Division's offices. (See address on the back of the title page.) DEFINITION OF TERMS Terms related to streamflow, water-quality, and other hydrologic data as used in this report, are defined below. See also the table for converting inch- pound units to the International System of units (SI) on the inside of the back cover. Acre-foot (AC-FT, acre-ft) is the quantity of water required to cover 1 acre to a depth of 1 foot and is equal to about 326,000 gallons or 1,233 cubic meters. Adenosine triphosphate (ATP) is an organic, phosphate-rich, compound important in the transfer of energy in organisms. Its central role in living cells makes it an excellent indicator of the presence of living material in water. A measure of ATP therefore provides a sensitive and rapid estimate of biomass. ATP is reported in micrograms per liter of the original water sample. Algae growth potential (AGP) is the maximum algal dry weight biomass that can be produced in a natural water sample under standardized laboratory conditions. The growth potential is the algal biomass present a stationary phase and is expressed as milligrams dry weight of algae produced per liter of sample. Aquifer is a geologic formation, group of formations, or part of a formation that contains sufficient saturated permeable material to yield significant quantities of water to wells and springs. Artesian means confined and is used to describe a well in which the water level stands above the top of the aquifer, tapped by the well. A flowing artesian well is one in which the water level is above the land surface. 28 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 Bacteria are microscopic unicellular organisms, typically spherical, rodlike, or spiral and threadlike in shape, often clumped into colonies. Some bacteria cause disease, while others perform an essential role in nature in the recycling of materials; for example, by decomposing organic matter into a form available for reuse by plants. Total coliform bacteria are a particular group of bacteria that are used as indicators of possible sewage pollution. They are characterized as aerobic or facultative anaerobic, gram-negative, nonspore-forming, rod- shaped bacteria which ferment lactose with gas formation within 48 hours at 35°C. In the laboratory these bacteria are defined as all the organisms which produce colonies with a golden-green metallic sheen within 24 hours when incubated at 35°C + 1.0°C on M-Endo medium (nutrient medium for bacterial growth). Their concentrations are expressed as number of colonies per 100 mL of sample. Fecal coliform bacteria are bacteria that are present in the intestines or feces of warm-blooded animals. They are often used as indicators of the sanitary quality of the water. In the laboratory they are defined as all organisms which produce blue colonies within 24 hours when incubated at 44.5°C + 0.2°C on M-FC medium (nutrient medium for bacterial growth). Their concentrations are expressed as number of colonies per 100 mL of sample. Fecal streptococcal bacteria are bacteria found also in intestines of warm-blooded animals. Their presence in water is considered to verify fecal pollution. They are characterized as Gram-positive, cocci bacteria which are capable of growth in brain-heart infusion broth. In the laboratory they are defined as all the organisms which produce red or pink colonies within 48 hours at 35°C + 1.0°C on KF-streptococcus medium (nutrient medium for bacterial growth). Their concentrations are expressed as number of colonies per 100 mL of sample. Bed material is the unconsolidated material of which a streambed, lake, pond, reservoir, or estuary bottom is composed. Biochemical oxygen demand (BOD) is a measure of the quantity of dissolved oxygen, in milligrams per liter, necessary for the decomposition of organic matter by microorganisms, such as bacteria. Biomass is the amount of living matter present at any given time, expressed as the mass per unit area or volume of habitat Ash mass is the mass or amount of residue present after the residue from the dry mass determination has been ashed in a muffle furnace at a temperature of 500°C for 1 hour. The ash mass values of zooplankton and phytoplankton are expressed in grams per cubic meter (g/m3), and periphton and benthic organisms in grams per square meter (g/m2). Dry mass refers to the mass of residue present after drying in an oven at 105°C for zooplankton and periphyton, until the mass remains unchanged. This mass represents the total organic matter, ash and sediment, in the sample. Dry-mass values are expressed in the same units as ash mass. Organic mass or volatile mass of the living substance is the difference between the dry mass and the ash mass and represents the actual matter. The organic mass is expressed in the same units as for ash and dry mass. Wet mass is the mass of b'ving matter plus contained water. Bottom material: See Bed material. Cells/volume refers to the number of cells of any organism which is counted by using a microscope and grid or counting cell. Many planktonic organisms are multicelled and are counted according to the number of contained cells per sample, usually milliliters (mL) or liters (L). Chemical oxygen demand (COD) is a measure of the chemically oxidizable material in the water, and furnishes an approximation of the amount of organic and reducing material present. The determined value may correlate with natural water color or with carbonaceous organic pollution from sewage or industrial wastes. 29 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 Clorophyll refers to the green pigments of plants. Chlorophyll a and b are the two most common green pigments in plants. Color unit is produced by one milligram per liter of platinum in the form of the chloroplatinate ion. Color is expressed in units of the platinum-cobalt scale. Contents is the volume of water in a reservoir or lake. Unless otherwise indicated, volume is computed on the basis of a level pool and does not include bank storage. Control designates a feature downstream from the gage that determines the stage-discharge relation at the gage. This feature may be a natural constriction of the channel, an artificial structure, or a uniform cross section over a long reach of the channel. Control structure as used in this report is a structure on a stream or canal that is used to regulate the flow or stage of the stream or to prevent the intrusion of salt water. Crest-stage station is a special form of partial-record station that records the highest stage of the stream that occurred between periodic visits to the station. A stage-discharge relation for each gage may be developed from discharge measurements made by indirect methods or by current meter. Cubic foot per second (cfs) is the rate of discharge representing a volume of 1 cubic foot passing a given point during 1 second and is equivalent to 7.48 gallons per second or 448.8 gallons per minute or 0.02832 cubic meters per second. Cubic foot per second-day (cfs-day) is the volume of water represented by a flow of 1 cubic foot per second for 24 hours. It is equivalent to 86,400 cubic feet, approximately 1.9835 acre-feet, about 646,000 gallons, or 2,445 cubic meters. Cubic feet per second per square mile (CFSM) is the average number of cubic feet of water flowing per second from each square mile of area drained, assuming that the runoff is distributed uniformly in time and area. Discharge is the volume of water (or more broadly, volume of fluid plus suspended sediment), that passes a given point within a given period of time. Instantaneous discharge is the discharge at a particular instant of time. Mean discharge (MEAN) is the arithmetic mean of individual daily mean discharges during a specific period. Dissolved refers to that material in a representative water sample which passes through a 0.45 urn membrane filter. This is a convenient operational definition used by Federal agencies that collect water data. Determinations of "dissolved" constituents are made on subsamples of the filtrate. Dissolved-solids concentration of water is determined either analytically by the "residue-on-evaporation" method, or mathematically by totaling the concentrations of individual constituents reported in a comprehensive chemical analysis. During the analytical determination of dissolved solids, the bicarbonate (generally a major dissolved component of water) is converted to carbonate. Therefore, in the mathematical calculations of dissolved-solids concentration, the bicarbonate value, in milligrams per liter, is multiplied by 0.492 to reflect the change. Diversity index is a numerical expression of evenness of distribution of aquatic organisms. The formula for diversity index is: __ s d = -1 ^_ Iog2 ^_ n n Where "i is the number of individuals per taxon, n is the total number of individuals, and s is the total number of taxa in the sample of the community. Diversity index values range from zero, when all the organisms in the sample are the same, to some positive number, when some or all of the organisms in the sample are different 30 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 Drainage area of a stream at a specified location is that area, measured in a horizontal plane, enclosed by a topographic divide from which direct surface runoff from precipitation normally drains by gravity into the stream above the specified point Figures of drainage area given herein include all closed basins, or noncontribution areas, within the area unless otherwise noted. Drainage basin is a part of the surface of the earth that is occupied by a drainage system, which consists of a surface stream or a body of impounded surface water together with all tributary surface streams and bodies of impounded surface water. Gage height (G.H.) is the water-surface elevation referred to some arbitrary gage datum. Gage height is often used interchangeably with the more general term "stage," although gage height is more appropriate when used with a reading on a gage. Gaging station is a particular site on a stream, canal, lake, or reservoir where systematic observations of hydrologic data are obtained. Ground-water station is a well at which observations of ground-water level are made, either continuously by recorder, or periodically by hand. In addition, various chemical or physical parameters may be obtained, usually on a periodic basis. Hardness of water is a physical-chemical characteristic that is commonly recognized by the increased quantity of soap required to produce lather. It is attributable to the presence of alkaline earths (principally calcium and magnesium) and is expressed as equivalent calcium carbonate (CaCO3). Hydrologic Bench-Mark Network is a network in small drainage basins around the country whose purpose is to provide consistent data on the hydrology, including water quality, and related factors in representative undeveloped watersheds nationwide, and to provide analyses on a continuing basis to compare and contrast conditions observed in basins more obviously affected by the activities of man. Hydrologic unit is a geographic area representing part or all of a surface drainage basin or distinct hydrologic feature as delineated by the Office of Water Data Coordination on the State Hydrologic Unit Maps; each hydrologic unit is identified by an eight-digit number. Land-surface datum (Isd) is a datum plane that is approximately at land surface at each ground-water observation well. Measuring point (MP) is an arbitrary permanent reference point from which the distance to the water surface in a well is measured to obtain the water level. Metamorphic stage refers to the stage of development that an organism exhibits during its transformation from an immature form to an adult form. This developmental process exists for most insects, and the degree of difference from the immature stage to the adult form varies from relatively slight to pronounced, with many intermediates. Examples of metamorphic stages of insects are egg-larva-adult or egg-nymph-adult Methylene blue active substances (MBAS) are apparent detergents. The determination depends on the formation of a blue color when methylene blue dye reacts with synthetic anionic detergent compounds. Micrograms per gram (ug/g) is a unit expressing the concentration of a chemical element as the mass (micrograms) of the element per unit mass (gram) of material analyzed. Micrograms per liter (UG/L, ug/L) is a unit expressing the concentration of chemical constituents in solution as mass (micrograms) of solute per unit volume (liter) of water. One thousand micrograms per liter is equivalent to one milligram per liter. Milligrams per liter (MG/L, mg/L) is a unit for expressing the concentration of chemical constituents in solution. Milligrams per liter represent the mass of solute per unit volume (liter) of water. Concentration of suspended sediment also is expressed in mg/L, and is based on the mass of sediment per liter of water-sediment mixture. Conversion of chemical concentrations in Mg/L to milliequivalents per liter can be done by using the factors in table 5. 31 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1991 Tabl* 5. Factors for conversion of chwoical constituents in milligrams p«r lit«r to milli«« »f»MS «* \ \ « *««»«« «n«w \ *ttvx^ ••OCn ^ 8r«l»e|t IwwwSerf \ EXPLANATION oi48 SURFACE-WATER STATION AND NUMBER -Mop j»«r*(Wti UTUAOO 0123456 3 4 Figure 13.-Rfo Camuy basin. 52 RIO CAMPY BASIN 50014600 RIO CAMOY AT TRES PUEBLOS SINKHOLE, PR LOCATION.~Lat 18°20'42', long 66°49'29', Hydrologic Unit 21010002, at Parque de las Cavernas del Rio Camuy, 1.8 mi (2.9 km) southeast from Bscuela Segunda Unidad de Santiago Palmer, 4.7 mi (7.6 km) west from Observatorio de Arecibo and 4.8 mi (7.7 km) northeast from Plaza de Lares. DRAINAGE! AREA.—Indeterminate. WATER-DISCHARGE RECORDS PERIOD OF RECORD.—June 1990 to current year. GAGE.—Water-stage recorder and crest-stage gage. Datum of gage is 612.21 ft (186.602 m), above mean sea level. REMARKS.—Records fair. Gage-height and precipitation satellite telemetry at station. EXTREMES FOR PERIOD JUNE TO SEPTEMBER 1990 AND WATER YEAR 1991.—Peak discharges greater than base discharge of 1,500 fts/s (42.5 mVs) and maximum (*) i Date Time Sept. 9,1990 1800 Discharge (fts/s) (mVs) •583 16.5 Gage height (ft) (m) •10.10 3.078 Date Time Oct. 7,1990 2245 Discharge (ftVs) (mVs) Gage height (ft) (m) '926 26.2 •11.97 3.648 Minimum daily discharge, 16 fts/s (0.453 mVs), July 30, 1990; 15 ftVs (0.425 mVs), Mar. 16, 17, 24, 25, Apr. 1, 1991. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAILY MEAN VALUES DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN OCT NOV JAN FEE MAR APR MAY JUN JUL AUG SEP 29 30 20 20 28 64 64 29 27 23 25 35 34 25 162 71 50 75 45 36 32 30 30 30 29 27 26 23 23 23 —— 1165 38.8 162 20 22 22 21 21 22 27 24 25 25 22 21 20 19 19 22 22 20 20 19 18 18 17 17 19 23 20 18 17 17 16 28 641 20.7 28 16 42 22 21 19 19 18 17 17 45 40 34 40 32 41 29 27 25 26 28 24 23 24 24 45 54 31 27 26 25 24 23 892 28.8 54 17 25 24 30 39 100 78 57 62 164 91 74 60 61 84 91 80 67 58 74 90 71 61 61 78 68 61 57 55 53 154 —— 2128 70.9 164 24 53 RIO CAMCTY BASIN 50014600 RIO CAMOY AT TUBS PUEBLOS 8IMKHOLB, PR—Continued DISCHARQB, CUBIC FBBT PBR SBCOHD, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUQ SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN 243 132 84 76 71 66 194 198 130 132 95 e79 e81 el!8 e!33 e!38 162 137 159 103 128 102 85 77 95 113 80 71 68 64 61 3475 112 243 61 59 57 55 64 92 65 65 77 56 51 51 51 48 46 45 45 44 43 42 42 41 42 41 40 53 51 41 40 38 37 —— 1522 50.7 92 37 36 36 37 35 34 34 33 33 32 32 31 30 30 31 29 29 28 28 28 28 28 28 28 27 27 25 25 25 25 25 28 925 29.8 37 25 27 25 24 24 24 23 23 22 22 22 21 22 22 22 21 21 22 21 21 21 21 20 20 19 20 20 20 20 21 19 19 669 21.6 27 19 19 19 19 19 75 34 27 28 23 24 30 31 27 23 21 20 20 20 26 71 30 24 22 21 22 21 20 20 —— 756 27.0 75 19 20 19 19 18 18 18 18 18 17 16 17 18 16 16 16 15 15 16 16 17 16 20 20 15 15 24 47 23 19 17 16 575 18.5 47 15 15 19 97 166 97 45 36 33 31 28 26 27 26 25 32 38 26 24 22 22 22 21 19 19 135 130 43 55 36 31 —— 1346 44.9 166 15 29 30 72 137 193 109 60 47 88 125 94 78 126 133 77 62 e74 e64 e46 e!45 elOO 66 50 44 41 40 37 35 34 33 32 2301 74.2 193 29 31 31 29 28 28 27 27 26 26 31 26 24 24 25 27 29 25 33 35 36 38 34 31 28 25 e24 e26 e47 e62 e80 —— 963 32.1 80 24 e64 e37 e32 31 30 28 53 87 53 37 33 30 30 28 28 65 50 35 31 29 28 27 26 26 25 24 25 100 106 73 64 1335 43.1 106 24 87 55 49 39 72 68 44 42 40 40 40 64 69 51 51 57 58 48 44 58 100 128 104 63 60 67 98 114 72 63 100 2045 66.0 128 39 143 102 79 69 64 61 80 65 57 55 54 53 51 49 48 49 53 47 46 60 79 68 58 50 52 61 85 84 62 53 —— 1937 64.6 143 46 WTR YR 1991 TOTAL 17849 MEAN 48.9 MAX 243 MIN 15 e Estimated 54 RIO CAMUY BASIN 50014800 RIO CANDY NEAR BAYANEY, PR LOCATION.—Lat 18°23'48", long 66°49'04", Hydrologic Unit 21010002, on left bank at Highway 488, 1.4 mi (2.2 km) southeast of school at Santiago, 0.9 mi (1.4 km) northwest from Escuela Manuel A. Rivera at Bayaney and 9.1 mi (14.6 km) upstream from Atlantic Ocean. DRAINAGE AREA.—Indeterminate. WATER-DISCHARGE RECORDS PERIOD OF RECORD.—May 1984 to current year. GAGE.—Water-stage recorder. Elevation of gage im 341 ft (104 m), from topographic map. REMARKS.—Record! fair. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.—7 years (1985-91), 110 ft1/* (3.115 mVs), 79,700 acre-ft/yr (98.3 hmVyr). EXTREMES FOR PERIOD OF RECORD.—Maximum discharge, 6,450 ft1/* (183 mj/s), Oct. 7, 1985, gage height, 17.66 ft (5.383 m), from rating curve extended above 300 ftj/s (8.50 mVs) on basis of step-backwater analysis; mln1 imim discharge, 25 ftVs (0.708 mVs), Apr. 26-28, 1989. EXTREMES FOR CURRENT YEAR.—Peak discharges greater than base discharge of 2,000 ftVs (56.6 •?/•) and maximum (*): Di scharge Date Oct. 8 Oct. 17 Time 0030 1545 *2,280 2,150 64.6 CO.9 Gage height (ft) (m) *12.10 3.688 11.80 3.597 Date Apr. 25 Time 2045 Discharge (ftVs) 2,220 62.9 Gage height (ft) (m) 11.97 3.648 Minimum discharge, 26 ft'/B (0.736 *V«), Feb. 1-4, Apr. 24, 25. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1C 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CAL YR WTR YR 587 288 147 132 122 10C 303 599 3C1 31C 191 155 173 354 409 C16 684 427 489 253 394 258 196 1C7 235 317 180 151 142 13 C 157 9045 292 C84 106 17940 1990 1991 133 114 107 18C 222 148 124 1C2 109 97 92 96 86 82 79 81 98 87 77 75 74 74 74 70 96 107 80 79 74 68 —— 3051 102 222 68 C050 TOTAL 3303C TOTAL 39223 CC 63 91 84 70 63 Cl 58 57 56 55 54 53 65 62 53 51 50 47 47 47 47 46 46 44 43 42 42 41 41 77 1722 55.5 91 41 3420 MEAN MEAN 65 45 42 40 39 39 37 34 34 33 33 32 32 32 31 31 32 30 30 30 30 29 28 28 27 27 27 27 28 28 27 1027 33.1 65 27 2040 90.5 MAX 107 MAX 28 26 26 34 35 122 50 47 34 34 56 58 46 38 33 29 29 29 71 246 89 53 45 42 41 40 38 37 —— —— —— 1456 52.0 246 26 2890 684 MIN 684 MIN 38 36 35 34 33 33 32 32 30 30 30 33 31 30 28 28 27 29 30 31 30 36 41 31 29 34 125 56 35 31 29 1107 35.7 125 27 2200 29 AC-FT 26 AC-FT 29 34 179 334 212 80 62 48 43 39 34 35 34 33 34 69 38 34 32 31 31 30 28 26 418 426 122 124 99 77 —— 2815 93.8 426 26 5580 65530 77800 63 58 165 496 469 268 122 96 187 277 188 160 329 336 202 158 190 157 113 341 257 141 106 96 90 86 81 79 77 75 73 5536 179 496 58 10980 70 69 65 62 61 60 58 56 55 69 57 52 51 52 60 65 55 57 184 150 222 114 91 78 69 61 67 109 138 183 —— 2540 84.7 222 51 5040 144 85 73 70 64 59 78 190 120 80 73 73 66 64 63 138 114 77 75 73 66 64 60 60 58 57 55 201 226 157 123 2906 93.7 226 55 5760 188 118 111 86 142 144 92 82 79 73 68 97 122 80 81 86 103 89 79 84 225 357 250 121 102 126 203 268 134 111 277 4178 135 357 68 8290 389 256 171 127 109 99 170 133 108 105 99 91 88 85 80 79 79 78 74 88 136 117 95 81 95 109 253 222 128 96 —— 3840 128 389 74 7620 55 RIO CAMOY BASIN 50014800 RIO CAMOY NEAR BAYANBY, PR—Continued MATER QDALITY RECORDS PERIOD OF RECORD.--NATBR YEARS JUNE 1984 TO CURRENT YEAR STRBAMFLON, SPECIFIC CON- TEMPERA- STRBAMFLON, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DOCTANCB TURB DATE TIME INSTANTANEOUS DUCTANCB TORS (CFS) (UMHOS) (DBG C) (CFS) (DMHOS) (DBG C) APR. 17 1318 38 200 25.0 AUG. 15 1230 81 268 22.5 MAY 23 1320 107 121 23.5 SBP. 26 1522 101 302 24.0 JDN. 18 1428 52 273 24.0 56 RIO GAUDY BASIN 50015700 RIO CANDY NEAR HATILLO, PR LOCATION.--Lat 18°27'44-, long 66°49'S6-, Hydrologie Unit 21010002, 1.8 mi (2.9 km) southwest of Hatillo pl« and 1.8 mi (2.9 km) southeast of Camuy plasa, 1.2 ml (1.9 km) couth of Plant* de Purification, and 3.3 mi (5.5 km) upstream from Atlantic Ocean. DRAXNAGE AREA.--Indeterminate. HATER-DISCHARGE RECORDS PERIOD OF RECORD.--June 1984 to current year. GAGE.—Water-stage recorder. Elevation of gage is 13 ft (4 m), from topographic map. REMARKS.—Record* fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.—7 years (1985-91), 176 ftVs (4.984 •?/•), 127,500 acre-ft/yr (157 hmVyr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 10,700 ftVs (303 mVs), revised, Oct. 7, 1985, gage height, 24.75 ft (7.544 m), from rating curve extended above 200 ft3/* (5.66 mVs) on basis of step-backwater analysis; minimum daily discharge, 25 ft'/s (0.708 mVs), May 30. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 2,500 ft'/« (70.8 mVs) and maximum (*)i Date Oct. 1 Oct. 8 Discharge Time (ftVs) (mVs) 2315 0315 3,070 3,970 86.9 112 Gage height (ft) (m) 15.91 4.849 17.44 5.316 Date Apr. 26 Discharge Time (ftVs) («Vs) 0030 •4,930 140 Gage height (ft) (m) *18.88 5.755 Minimum daily discharge, 37 ftVs (1.048 mVs), Feb. 2, 3, Mar. 16, 17, 21. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JON JUL AUQ SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN CAL YR WTR YR 861 691 176 147 136 110 138 1310 601 809 271 204 290 544 588 1470 2270 e!600 e820 e!300 e820 e620 374 292 310 757 313 233 237 216 240 18748 605 2270 110 1990 1991 338 175 148 348 SOI 269 183 271 174 134 121 126 109 103 96 103 140 187 104 95 90 89 87 80 97 157 95 91 81 73 —— 4665 155 501 73 TOTAL 51394 TOTAL 61614 68 66 122 119 83 72 73 69 67 65 64 63 62 65 88 67 60 60 58 53 52 52 53 51 50 48 47 47 46 46 64 2000 64.5 122 46 MEAN 141 MEAN 169 196 75 66 60 58 59 56 54 53 51 51 50 49 48 47 46 48 e45 e45 e45 e45 e44 e43 e43 e42 e40 e40 e40 e42 •42 e40 1663 53.6 196 40 MAX MAX e41 e37 e37 e47 e44 167 74 69 e52 eSl 72 93 71 57 e52 eSl eSl eSl e80 586 130 75 62 56 55 e52 e49 e47 —— 2309 82.5 586 37 2270 MIN 25 2270 MIN 37 e46 e48 e45 e44 e42 e41 e41 e40 e40 e39 e38 e38 e41 e39 e38 e37 e37 e39 e40 e43 37 44 55 40 38 39 242 80 50 43 41 1525 49.2 242 37 39 40 119 500 512 111 83 63 58 53 48 50 48 47 46 83 52 44 43 41 41 41 39 38 462 1600 224 179 124 72 —— 4900 163 1600 38 57 53 223 813 668 627 143 99 194 477 252 251 397 786 324 272 414 365 144 372 540 193 122 101 92 89 81 71 69 65 63 8417 272 813 53 61 61 58 56 55 54 58 55 54 67 59 S3 52 52 62 68 61 61 286 243 368 178 123 93 81 69 76 135 197 241 —— 3137 105 368 52 219 99 83 78 76 66 61 231 200 91 79 74 68 63 65 171 180 93 84 73 67 64 62 60 59 56 55 161 370 185 103 3396 110 370 55 244 131 115 84 114 216 95 82 79 72 67 68 174 81 82 78 111 94 77 66 226 672 498 157 112 147 146 509 176 129 333 5235 169 672 66 756 522 290 165 129 114 214 281 162 138 131 109 101 97 93 88 89 87 80 77 143 167 111 88 94 134 316 495 223 125 —— 5619 187 756 77 Estimated 57 RIO GAUDY BASIN 50015700 RIO CAMUY NEAR HATILLO, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.—WATER YEARS AUGUST 1984 TO CURRENT YEAR STREAMPLOW, SPECIFIC CON- TEMPERA- STRBAMPLON, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DBG C) (CFS) (UMHOS) (DBG C) AUG. 01 1239 162 290 23.5 MAY 23 0815 66 244 25.0 APR. 17 0930 49 220 24.5 58 THIS PAGE WAS LEFT BLANK INTENTIONALLY EXPLANATION A 0284 SURFACE-WATER STATION AND NUMBER ^0205 QUALITY-OF-WATER STATION AND NUMBER Y7 020050 QUALITY-OF-WATER PARTIAL RECORD v STATION AND NUMBER 204 WELL AND WELL NUMBER 026140 LAKE-ELEVATION STATION 0123456 01234 Figure 14.--Rio Grande de Arecibo basin. 60 RIO GRANDB DB ARBCIBO BASIN 50020500 RIO ORANDB DB ARBCIBO NBAR ADJUNTAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°10'54", long 66°44'12", at Highway 135 bridge, 1.0 mi (1.6 km) upstream from Lago Adjuntas, and 1.5 mi (2.4 km) northwest of Adjunta* plama. DRAINAQB ARBA.--12.7 mia (32.9 km3 ) this does not include 6.0 mi* (15.6 km2) above Lago OarBas. PERIOD OF RECORD.—Water years 1969-74, 1979 to current year. WATBR-QDALITY DATA, WATBR YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATB OCT 1990 23... JAN 1991 09... FEB 25... APR 11... JUN 21... ADO 19... TIME 0845 1000 1330 1215 1230 1400 DIS- CHARGE, INST. CUBIC FEET PER SECOND 137 29 12 15 12 17 SPE- CIFIC CON- DUCT- ANCE (US/CM) 230 278 333 383 409 348 PH (STAND- ARD UNITS) 7.8 7.8 8.3 8.0 8.2 8.2 TEMPER- ATURE WATBR (DBG C) 21.5 19.5 24.5 22.5 26.0 28.0 TUR- BID- ITY (NTU) 5.4 1.1 1.3 15 1.5 1.8 OXYGEN, DIS- SOLVED (MG/L) 8.0 9.0 9.7 9.8 7.4 8.1 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 94 101 120 117 94 107 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 15 <10 17 25 13 13 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K120000 K100 K980 K150 380 K690 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 7900 260 350 270 410 470 DATB OCT 1990 23... JAN 1991 09... FEB 25... APR 11... JUN 21... AUG 19... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CACO3) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 81 0 21 7.0 14 150 0 42 11 26 110 0 30 9.1 22 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATE RIDE, DIS- TOT FBT SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 0.7 1.5 0.9 3.5 0.9 2.2 CACO3 79 95 110 100 110 110 AS 8) AS S04) AS CL) <0.5 14 <0.5 14 10 21 31 32 DATB OCT 1990 23... JAN 1991 09... FBB 25... APR 11... JUN 21... AUG 19... FLUO- RIDE, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS 8102) 26 — — 24 — 32 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 152 -- -- 212 -- 203 SOLIDS, DIS- SOLVED (TONS PER DAY) 56 — — 8.80 — 9.33 K - non- ideal count SOLIDS, RESIDUE TOTAL NITRO- NITRO- NITRO- AT 105 GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 SUS- TOTAL TOTAL TOTAL FENDED (MG/L (MG/L (MG/L (MG/L) AS N) AS N) AS N) 13 4 6 20 5 13 0.980 0.850 0.960 0.940 1.18 0.800 0.020 0.050 0.140 0.160 0.120 0.080 1.00 0.900 1.10 1.10 1.30 0.880 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.120 0.080 0.050 0.140 0.190 0.080 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.18 0.52 0.45 0.56 0.51 0.22 61 RIO GRANDS DB ARBCZBO BASIN 50020500 RIO GRANDB DB ARBCIBO MR ADJUNTAS, PR—Continued MATER QUALITY DATA, WATER YBAR OCTOBER 1990 TO 8BPTBHBBR 1991 DATE OCT 1990 23... JAN 1991 09... FBB 25... APR 11... JON 21... AUG 19... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.60 0.50 0.70 0.70 0.30 NITRO- GEN, TOTAL (MG/L AS N) 1.3 1.5 1.6 1.8 2.0 1.2 NITRO- GEN, TOTAL (MG/L AS N03) 5.8 6.6 8.4 8.0 8.9 5.2 PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.070 <1 0.070 0.240 0.210 2 0.240 0.140 BARIUM, BORON, TOTAL TOTAL RECOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS BA) AS B) <100 <10 — — <100 50 — — CHRO- CADMIUM MIUM, TOTAL TOTAL RECOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CD) AS CR) <1 2 — — 3 3 — — COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 10 — — 40 — — DATS OCT 1990 23... JAN 1991 09... FBB 25... APR 11... JON 21... AUG 19... IRON, TOTAL RECOV- ERABLE (UG/L AS FB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LBNB BLUB ACTIVE SUB- STANCB (MG/L) 580 1200 50 190 <0.10 0.20 10 <0.010 40 <0.010 0.04 0.08 62 RIO GRANDS DE ARBCIBO BASIN 50025000 RIO ORANDB DE ARBCIBO NEAR UTUADO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°18'11 B , long 66«41'59 B , at bridge near Highway 10 at km 56.4, 0.5 mi (0.8 km) downatrc R£o de Caguana, and 2.5 mi (4.0 km) north of Utuado plaia. DRAINAGE ARBA.--66.0 ml2 (170.9 km2) this excludes 6.0 ml2 (15.5 km2 ) upstream from Lago Gariai to Rio Guayan*M in the Rio Tallaboa basin. PERIOD OF RECORD.--Water yean 1959-74, 1979 to current year. WATER-QUALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 from DATB OCT 1990 31... DEC 20... FBB 1991 22... APR 16... JUN 24... AUQ 20... THIS 0915 0950 0930 1330 1245 1225 DIS- CHARGE, INST. CUBIC FEET PBR SECOND 418 87 64 76 75 66 SPE- CIFIC CON- DUCT- ANCE (US/CM) 213 205 289 232 287 276 PH (STAND- ARD UNITS) 8.0 7.7 7.8 7.9 8.0 8.1 TEMPER- ATURE HATER (DBG C) 23.0 21.0 22.5 28.5 29.5 29.0 TUR- BID- ITY (NTU) 18 5.7 2.8 19 3.7 31 OXYGEN, DIS- SOLVED (MG/L) 8.3 8.6 8.1 7.8 7.3 7.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 96 96 93 100 95 97 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 10 <10 <10 22 <10 10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3700 2100 K1500 31000 3200 3300 STREP- TOCOCCI FECAL, (COLS. PBR 100 ML) 520 270 580 3600 570 730 DATB OCT 1990 31... DEC 20... FEB 1991 22... APR 16... JUN 24... AUG 20... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH NAT DI8- (MG/L TOT FLD SOLVED AS MG/L AS (HG/L CACO3) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MO) AS NA) 82 1 22 6.6 12 100 0 28 8.0 13 88 2 24 6.9 12 SODIUM AD- SORP- TION RATIO POTAS- ALKA- LINITY CHLO- SIUM, NAT WH SULFATE RIDE, DIS- TOT FBT SULFIDE DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MQ/L MG/L AS (MG/L AS K) 0.6 1.8 0.6 2.1 0.6 2.7 CACO3 66 87 93 82 89 90 (MG/L <0.5 18 <0.5 27 13 (HG/L AS S) AS 804) AS CL) 12 14 13 DATB OCT 1990 31... DBC 20... FBB 1991 22... APR 16... JUN 24... AUG 20... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 — -- 0.20 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 29 — — 26 — 23 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 141 -- -- 167 -- 142 SOLIDS, DIS- SOLVED (TONS PBR DAY) 159 — — 34 — 25 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 28 <1 <1 17 14 38 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.18 1.17 0.970 1.03 1.05 1.04 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.030 0.030 0.070 0.050 0.060 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 1.20 1.20 1.00 1.10 1.10 1.10 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.070 0.030 0.020 0.170 0.130 0.070 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.23 — — 0.33 0.27 0.53 non-ideal count RIO GRANDS DB ARBCIBO BASIN 50025000 RIO GRANDS DB ARBCIBO NEAR UTUADO, PR--Continu«d HATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 63 DATE OCT 1990 31... DBC 20... PEB 1991 22... APR 16... JUN 24... AUG 20... DATE OCT 1990 31... DBC 20... PEB 1991 22... APR 16... JUN 24... AUG 20... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 «0.20 «0.20 0.50 0.40 0.60 IRON, TOTAL RECOV- ERABLE (UG/L AS PE) NITRO- GEN, TOTAL (MG/L AS N) 1.5 — — 1.6 1.5 1.7 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 6.6 -- -- 7.1 6.6 7.5 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.060 0.080 0.070 0.170 0.140 0.240 MERCURY TOTAL RECOV- ERABLE (UG/L AS BO) ARSENIC TOTAL (UG/L AS AS) .1 -- -- <1 — -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 ~ — <100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 — -- 10 — -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 2 -- -- 3 -- -- PHENOLS TOTAL (UG/L) COPPBR, TOTAL RECOV- ERABLE (UG/L AS CU) 30 — — 20 — -- MBTBY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1900 2000 90 80 <0.10 0.10 20 «0.010 <0.010 0.03 0.03 S 1 * V ! < 4 1 i * t gj , & - * •< gb < S ' fa X nj r W fv < u a c 31 * « DO • Si c S B • m c H g s [3 Ed 1 a g r M ' „ E 1 1 o o a a . c in ' in • rt f IA N O O IA i » s i 1 N 2 * 11 ' & ! i IH « » -5 3 9 " » 9 S H O M ' 9 J M H O t0 ) 1 £ m « 0 U rt H n ? 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W SB i 5 * o M 3 H O P*t BE P S S JB K U H « N in o 0) rt SB SB H H 00 00 rt N N N ss BO W S O O O r- o in n rt rt EE U U "* N riin SB SB 99 in in rt rt rt rt rt rt O rt N N 11 8 S o r* . 9 ^f ^ n r* ii O rt 0) 01 0) 0) rt rt Pti PG ^4 p4 M* P^ 2 b O 3! 1 41 1 H 9 65 RIO GRANDB DB ARBCIBO BASIN 50026050 RIO CAONILLAS ABOVE LAOO CAONILLAS NEAR JAYUYA, PR WATER-QUALITY RECORDS LOCATION.—Lat 18®13'26-, long 66°38'22", 300 ft (91 m) off Highway 531, 700 ft (213 m) upstream from Caonillas, 3.3 mi (5.3 km) northwest of Jayuya plaza. DRAINAGE AREA.--40.4 mi3 (104.6 km1). PERIOD OF RECORD.—Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 Lago DATE OCT 1990 23... JAN 1991 09... FBB 25... APR 11... JUN 21... AUG 19... TIME 1230 1155 1030 0830 0915 1110 DIS- CHARGE, INST. CUBIC FEET PER SECOND 281 41 29 33 34 41 SPE- CIFIC CON- DUCT- ANCE (US/CM) 154 250 229 216 174 158 PH (STAND- ARD UNITS) 8.0 7.1 8.1 7.6 7.8 7.9 TEMPER- ATURE HATER (DBG C) 23.5 23.0 23.0 21.0 23.5 25.5 TUR- BID- ITY (NTU) 7.0 1.3 1.0 1.0 26 0.40 OXYGEN, DIS- SOLVED (MG/L) 8.5 9.0 8.5 8.8 8.1 7.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 102 105 100 99 96 97 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 12 <10 12 10 15 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 400 210 K33 100 K600 K290 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 350 20 K19 110 K1000 210 DATE OCT 1990 23... JAN 1991 09... FEB 25... APR 11... JUN 21... AUG 19... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L MAGNE- SIUM, SODIUM, DI8- DIS- SOLVED SOLVED (MG/L (MG/L CACO3) CACO3 AS CA) AS MG) AS NA) 54 0 14 79 0 21 89 0 21 SODIUM AD- SORP- TION RATIO 6.5 12 6.6 12 ALKA- POTAS- LINITY 8IUM, WAT WH DIS- SOLVED (MG/L AS K) 4.6 8.5 0.5 1.3 0.6 1.3 0.5 1.4 CHLO- SULFATB RIDE, TOT PET SULFIDE DIS- DIS- FIBLD TOTAL SOLVED SOLVED MG/L AS (MG/L (MG/L (MG/L CACO3 AS 8) AS SO4) AS CL) 49 75 79 68 56 59 <0.5 11 <0.5 14 13 9.6 13 10 DATE OCT 1990 23... JAN 1991 09... FBB 25... APR 11... JUN 21... AUG 19... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- <0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 24 — — 23 — 20 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 102 -- -- 132 -- 130 K * non- ideal count RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITB NO2+NO3 AMMONIA ORGANIC (TONS SU8- TOTAL TOTAL TOTAL TOTAL TOTAL PER PENDBD (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 77.7 11.6 14.4 5 8 <1 1 27 15 1.09 0.490 0.390 — 0.690 — 0.010 0.010 <0.010 <0.010 0.020 <0.010 1.10 0.500 0.400 0.460 0.710 0.550 0.020 0.020 0.020 <0.010 0.080 0.020 — 0.38 0.28 — 0.32 — 66 RIO ORANDB DB ARBCIBO BASIN 50026050 RIO CAOMILLA8 ABOVE LAOO CAONILLAS NEAR JAYUTA, PR--Continued MATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 23... JAN 1991 09... VBB 25... APR 11... JUN 21... AUG 19... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) <0.20 0.40 0.30 <0.20 0.40 <0.20 NITRO- GEN, TOTAL (MG/L AS N) — 0.90 0.70 — 1.1 — NITRO- GEN, TOTAL (MQ/L AS N03) -- 4.0 3.1 -- 4.9 — PHOS- PHORUS TOTAL (MG/L AS P) 0.040 0.050 0.060 0.070 0.130 0.090 ARSENIC TOTAL (UG/L AS AS) 20'50", long 66°40'02", at pedestrian bridge, 0.7 mi (1.1 km) downstream from Lago and 6.6 mi (10.6 km) we«t of Florida plaza. DRAINAOB ARBA.--169 mi2 (436 km*) doe* not include 6.0 mi2 (15.6 kB?) above Lago Oarxa*. PERIOD OF RECORD.--Water year* 1970-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 Do* Boca* DATE OCT 1990 19... DEC 20... FBB 1991 15... APR 16... JUN 24... AOQ 20... TIME 1315 0820 0900 1045 1020 1020 DIS- CHARGE, INST. CUBIC FEET PER SECOND 1860 31 29 1490 20 19 SPE- CIFIC CON- DUCT- ANCE (OS/CM) 165 201 227 210 209 221 PH (STAND- ARD UNITS) 7.7 7.2 7.5 7.2 7.5 7.6 TEMPER- ATURE WATER (DEG C) 25.0 23.5 23.5 25.0 27.5 28.0 TUR- BID- ITY (NTU) 170 3.5 4.0 3.0 2.1 23 OXYGEN, DIS- SOLVED (MG/L) 7.7 4.7 6.5 4.0 6.1 5.2 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 92 55 75 47 76 65 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 32 11 <10 16 19 13 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K7100 K20 K49 2400 K60 100 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 11000 K140 130 K40 44 K23 DATE OCT 1990 19... DEC 20... FBB 1991 15... APR 16... JUN 24... AUG 20... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS CAC03) CACO3 MG/L AS (MG/L 60 0 17 75 0 20 80 0 25 MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS HA) SODIUM AD- SORP- TION RATIO 6.1 10 ALKA- POTAS- LINITY SIUM, HAT WH DIS- TOT FET SULFTDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 4.3 9.7 0.5 2.7 0.5 2.2 CACO3 6.5 9.4 0.5 2.8 56 76 75 67 72 75 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L <0.5 13 <0.5 12 13 (MG/L AS S) AS 804) AS CL) 12 11 10 SOLIDS, RESIDUE DATE OCT 1990 19... DEC 20... FEB 1991 15... APR 16... JUN 24... AUG 20... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 19 — — 20 — 20 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 111 -- -_ 122 — 130 SOLIDS, DIS- SOLVED (TONS PER DAY) 558 — _ 489 — 6.70 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 158 <1 13 4 3 1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.810 0.560 0.590 0.240 0.290 0.180 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.090 0.040 0.010 0.020 0.030 0.020 NITRO- GEN, N02+NO3 TOTAL (MG/L AS N) 0.900 0.600 0.600 0.260 0.320 0.200 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.130 0.050 0.030 0.080 0.120 0.060 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.37 0.25 0.47 0.42 0.18 0.34 non-ideal count 69 RIO GRANDS DB ARBCIBO BASIN 50027250 RIO GRANDE DB ARBCIBO BELOW LAQO DOS BOCAS NEAR FLORIDA, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 NITRO- CHRO- GBN,AM- BARIUM, BORON, CADMIUM MIUM, DATE OCT 1990 19... DEC 20... FBB 1991 15... APR 16... JUN 24... AUG 20... DATE OCT 1990 19... DBC 20... FBB 1991 15... APR 16... JUN 24... AUG 20... MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.30 0.50 0.50 0.30 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 8400 -- -- 190 -- -- NITRO- GEN, TOTAL (MG/L AS N) 1.4 0.90 1.1 0.76 0.62 0.60 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 15 — — 3 — — NITRO- GEN, TOTAL (MG/L AS NO3) 6.2 4.0 4.9 3.4 2.7 2.7 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 220 — — 110 — — PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.160 <1 0.040 0.020 0.020 <1 0.030 0.020 MERCURY TOTAL SBLB- RECOV- NIUM, BRABLB TOTAL (UG/L (UG/L AS HG) AS SB) 0.10 <1 — — 1.1 <1 — — TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 — — <1 — — TOTAL RECOV- ERABLE (UG/L AS B) <10 — — 30 -- — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 30 -- -- <10 — -- TOTAL TOTAL RECOV- RECOV- ERABLE ERABLB (UG/L (UG/L AS CD) AS CR) <1 6 — — <1 1 — — — — — CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) <0.010 <1 — — <0.010 3 — — COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) 60 — — 10 — — — MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) <0.01 — — 0.01 — — 70 RIO GRANDE UK ARBCIBO BASIN 50027750 RIO GRANDE DB ARBCIBO ABOVE ARBCIBO, PR LOCATION.—Lat 18°25'22', long 66°41'58', Hydrologic Unit 21010002, 0.5 mi (0.8 km) upstream from Rfo Tanami, 3.6 mi (5.8 km) south of Arecibo and 4.9 mi (7.9 km) above mouth, and 10.4 mi (16.7 km) downstream from Lago Dos Bocas. DRAINAGE ARBA.--200 mi* (520 km1 ), approximately, of which an undetermined amount does not contribute directly to surface runoff. WATER-DISCHARGE RECORDS PERIOD OF RECORD.—April 1982 to current year. GAGE.—Hater-stage recorder. Elevation of gage is 30 ft (9 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Flow regulated by Lago Dos Bocas Dam 10.4 mi (16.7 km) upstream from gage. Gaffe-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--9 years (1983-91), 430 ft}/s (12.18 mV«), 29.20 in/yr (742 mm/yr), 311,500 acre-ft/yr (384 hmVyr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 45,800 ft'/» (1,300 m}/s), May 18, 1985, gage height, 18.22 ft (5.553 m), from floodmark, from rating curve extended above 2,400 ft*/s (68.0 mVs) on basis of slope-area measurement of peak flow; minimum discharge, 30 ft3/" (0.850 mVs), Mar. 30, 1986. EXTREMES FOR CURRENT YEAR.—Peak discharges greater than base discharge of 4,300 ft'/» (122 m?/«) and maximum (*) i Date Time Discharge (ftVs) (mVs) Gage height (ft) (m) Date Til Oct. 17 2345 *4,100 116 *9.27 2.825 Minimum daily discharge, 43 ft3/" (1.218 mVs), June 25. Discharge (ftVs) (mVs) Gage height (ft) (m) DAY OCT DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES NOV DEC JAN FEE MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 758 586 612 662 631 233 82 632 286 1350 782 626 513 573 808 1070 1630 2010 1910 1060 1260 1170 930 1010 1090 1310 1580 1470 1280 1210 1090 30214 975 2010 82 59930 6.96 8.03 1990 1991 838 750 807 470 718 693 713 669 583 462 573 609 672 600 661 708 602 327 169 149 190 80 79 136 90 620 462 413 579 413 —— 14835 494 838 79 29430 3.53 3.94 TOTAL 115242 TOTAL 134549 133 194 532 508 97 369 e383 e474 e659 e240 544 576 643 652 259 67 83 151 233 202 319 157 370 169 122 60 233 elOO e94 e210 e220 9053 292 659 60 17960 2.09 2.41 MEAN MEAN e!40 e450 e!30 elOO e80 e74 «70 511 96 283 345 534 222 213 112 71 95 237 326 422 473 568 220 78 361 151 156 221 199 387 186 7511 242 568 70 14900 1.73 2.00 316 MAX 369 MAX 91 76 109 196 99 69 195 433 263 164 544 618 259 246 83 249 494 259 362 240 157 110 120 160 67 275 408 144 —— 6490 232 €18 67 12870 1.66 1.72 2010 MTN 2010 MTN 64 273 93 166 387 320 139 368 185 122 140 78 e63 e!47 el43 «70 189 65 269 107 131 240 320 241 391 373 485 501 248 447 534 7299 235 534 63 14480 1.68 1.94 38 AC-FT 43 AC-FT 711 247 163 685 333 199 240 354 487 522 652 542 109 168 564 768 €76 135 82 148 252 612 314 215 190 279 479 173 346 291 —— 10936 365 768 82 21690 2.60 2.91 228600 266900 438 454 496 395 553 394 457 535 473 743 1030 291 531 426 444 767 201 515 237 237 763 507 465 105 107 60 53 614 360 438 552 13641 440 1030 53 27060 3.14 3.62 CFSM 2.26 CFSM 2.63 98 148 180 464 552 579 323 77 52 500 119 71 154 166 108 63 162 71 60 415 94 49 48 56 43 212 418 488 104 59 —— 5933 198 579 43 11770 1.41 1.58 IN. 30. IN. 35. 244 406 244 110 303 523 243 644 426 500 587 375 101 224 126 328 299 87 433 133 188 724 262 72 57 275 179 276 711 580 404 10064 325 724 57 19960 2.32 2.67 62 75 325 318 90 218 482 536 411 465 107 60 52 212 102 64 116 99 61 58 449 76 81 491 495 157 183 550 556 539 559 510 414 8836 285 559 52 17530 2.04 2.35 173 160 527 600 449 401 99 153 563 424 326 509 468 100 482 424 247 184 399 203 503 209 289 404 512 300 305 97 54 173 —— 9737 325 600 54 19310 2.32 2.59 Estimated 71 RIO GRANDS DB ARBCIBO BASIN 50027750 RIO GRANDS DB ARBCIBO ABOVB ARBCIBO, PR—Continued WATER QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS APRIL 1982 TO CURRENT YEAR STREAMFLOW, SPECIFIC CON- TEMPERA- STRBAMFLOW, SPECIFIC CON- TBMPERA- DATB TIME INSTANTANBODS DUCTANCB TORE DATE TIME INSTANTANEOUS DUCTANCB TORE (CFS) (UMHOS) (DBG C) (CFS) (UMHOS) (DBG C) APR. 22 1125 121 230 26.0 AUG. 16 0930 92 242 22.5 JDN. 25 1145 43 273 28.0 72 RIO ORAKDB IX ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR LOCATION.—Lat 18°18'02", long 66°46'58 B , Hydrologic Unit 21010001, on downstream side of left abutment of bridge on Highway 111, 1.2 ml (1.9 km) upstream from natural tunnel, 1.5 ml (2.4 km) northeast of Angeles, and 5.8 ml (9.3 km) northwest of Utuado. DRAINAGE AREA.--18.4 ml 1 (47.7 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—June 1944 to June 1958 (dally itage and two to four measurement! per month by Puerto Rico Water Reiourcei Authority), November 1959 to current year. GAOE.—Water-stage recorder and crest-stage gage. Datum of gage is 938.32 ft (286.000 m) above mean sea level. Datum of gage was lowered 3.00 ft (0.914 m) on Oct. 1978. Prior to Nov. 17, 1966, non-recording gage and Nov. 17, 1966 to Sept. 30, 1978 recording gage, both at present site. REMARKS.—Record* fair except those for estimated daily discharges, which are poor. AVERAGE DISCHARGE.--31 yean (1961-91), 48.1 ftVs (1.362 •?/•), 35.50 in/yr (902 mm/yr), 34,850 acre-ft/yr (43.0 hmVyr); median of yearly mean discharge*, 48 ft1/! (1.36 •?/•), 34,800 acre-ft/yr (43 hmVyr). EXTREMES FOR PERIOD OF RECORD.—Maximum discharge, 12,190 ftV« (345 •?/•), May 18, 1985, gage height, 17.45 ft (5.319 m) new datum in use, from floodmark and recorder, from rating curve extended above 500 ft1/* (14.2 •?/•) on basis of slope-area measurement of peak flow; minimum discharge, 6.6 ft1/* (0.187 mVs), June 12, 1977. EXTREMES FOR CDRRBNT YEAR.--Peak discharges greater than base discharge of 3,000 ft1/* (85.0 mVi) and maximum (*) i Date Oct. 1 May 5 Time 1600 1745 Discharge (ftVs) (m *10,270 3,190 291 90.3 Gage height (ft) (m) *16.74 5.102 12.08 3.682 Date May 10 Time 1715 Discharge (ft'/a) (»'/•) 3,280 92.9 Gage height (ft) (m) 12.20 3.718 Minimum daily discharge, 11 ft1/* (0.312 mVs), Mar. 15-17. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JDN JUL ADO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 534 186 136 123 113 97 184 97 108 89 74 68 91 173 190 157 119 170 170 116 201 127 111 105 166 149 114 103 94 87 82 4334 140 534 68 8600 7.60 8.76 1990 1991 78 74 70 70 96 71 68 61 58 55 71 63 59 56 54 54 52 50 50 59 56 65 49 52 52 48 45 43 41 40 —— 1760 58.7 96 40 3490 3.19 3.56 TOTAL 16504 TOTAL 18530 40 39 47 40 37 36 34 34 34 32 33 31 32 34 31 30 30 29 28 28 28 30 28 28 27 26 26 25 25 25 36 983 31.7 47 25 1950 1.72 1.99 MEAN MEAN 30 27 25 25 24 24 24 23 23 23 22 22 22 21 21 20 20 19 19 19 18 18 18 18 18 18 18 18 18 18 18 651 21.0 30 18 1290 1.14 1.32 45.2 MAX 50.8 MAX 21 19 25 33 97 47 25 21 20 36 34 28 39 25 22 21 20 22 29 25 21 19 18 17 17 17 17 18 —— 753 26.9 97 17 1490 1.46 1.52 534 MIN 11 534 MIN 11 18 17 16 16 16 15 15 15 14 13 14 13 12 12 11 11 11 14 12 12 14 27 19 13 13 65 58 19 16 14 13 548 17.7 65 11 1090 .96 1.11 AC-FT AC-FT 13 28 35 75 63 23 19 18 18 16 18 22 19 16 59 36 19 18 16 16 15 15 14 14 216 e45 e26 e!9 16 16 —— 943 31.4 216 13 1870 1.71 1.91 32740 36750 32 78 34 69 338 e93 46 38 105 285 166 124 122 83 65 55 51 57 50 96 54 45 42 41 42 40 39 38 37 37 37 2439 78.7 338 32 4840 4.28 4.93 CFSM 2.46 CFSM 2.76 36 35 33 31 31 30 29 28 27 26 25 25 25 33 38 31 59 81 39 46 40 36 31 29 27 26 27 57 47 95 —— 1123 37.4 95 25 2230 2.03 2.27 IN. 33.37 IN. 37.46 40 32 31 32 28 26 124 194 63 41 e37 e35 e39 42 49 102 157 85 e51 39 36 36 37 34 33 33 32 48 34 31 55 1656 53.4 194 26 3280 2.90 3.35 70 39 42 45 144 75 52 47 44 41 39 54 40 70 49 61 46 e39 37 39 87 97 57 40 50 43 88 59 42 37 54 1727 55.7 144 37 3430 3.03 3.49 145 e70 55 e49 e45 44 51 45 41 44 44 61 47 40 41 56 51 41 40 73 98 58 46 42 43 39 70 52 43 39 —— 1613 53.8 145 39 3200 2.92 3.26 Estimated 73 RIO ORANDE US ARBCIBO BASIN 50028000 RIO TANAMA HBAR UTUADO, PR- -Continued WATER-QUALITY RECORDS PERIOD OF RECORD.— Water year* 1958 to current year. PERIOD OF DAILY RECORD.— SUSPENDED SEDIMENT DISCHARGE* January 1968 to current year. INSTRUMENTATION. — US D-49 Sediment sampler since October 1968. Automatic sediment sampler since 1990. REMARKS. — Sediment samples were collected by a local observer on a weekly basis and during high flow event*. Estimates for period of mining daily record were wide from a sediment transport curve developed from a period of record over 5 yean. EXTREMES FOR PERIOD OF DAILY RECORD. -- SEDIMENT CONCENTRATIONS t Maximum daily mean, 20,400 mg/L November 27, 1968; minimum daily mean, 0 mg/L during water year 1985. SEDIMENT LOADS* Maximum daily, 167,000 tone (152,000 tonne*) May 18, 1985, minimum daily, 0.0 ton (0.0 tonne) •everal day* during many year*. daily mean, 2,310 mg/L October 17, 1989; minimum daily EXTREMES FOR CURRENT YEAR.— SEDIMENT CONCENTRATIONS t 3.0 mg/L several day*. SEDIMENT LOADS* Maximum daily, 11,400 tons (10,400 tonne*) October 17, 1989; minimum daily, 0.14 ton (0.13 tonne) •everal day*. HATER-QUALITY DATA, HATER YEARS OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 11... DEC 26... FEB 1991 19... APR 16... JUN 11... ADO 07... TIME 1130 0935 1030 1715 1020 1200 DIS- CHARGE, INST. CUBIC FEET PER SECOND 75 27 27 25 26 52 SPE- CIFIC CON- DUCT- ANCE (US/CM) 151 160 162 133 172 209 PH (STAND- ARD UNITS) 7.8 8.0 7.8 7.4 7.9 7.8 TEMPER- ATURE WATER (DBG C) 23.0 19.0 21.0 24.0 24.5 24.0 TUR- BID- ITY (NTU) 7.9 2.4 10 93 1.6 9.0 OXYGEN, DIS- SOLVED (MG/L) 8.5 9.0 8.4 7.7 8.1 8.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 101 99 95 93 99 100 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 — 12 31 10 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS. / 100 ML) 480 K70 2000 K12000 96 270 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 240 210 4100 K20000 130 330 DATE OCT 1990 11... DEC 26... FEB 1991 19... APR 16... JUN 11... AUG 07... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL HH WAT DIS- (MG/L TOT FLD SOLVED AS MQ/L AS (MG/L CAC03) CAC03 50 0 12 47 1 12 59 0 15 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MQ/L (MG/L AS CA) AS MO) AS NA) SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT Wfl DIS- TOT FBT SULFIDB SOLVED FIELD TOTAL (MG/L MQ/L AS (MG/L AS K) 4.9 7.5 0.5 2.0 4.2 6.1 0.4 2.6 5.3 7.1 0.4 1.9 CACO3 49 160 53 33 57 46 CHLO- SULFATE RIDE, DIS- DIS- SOLVED SOLVED (MQ/L 24'52", long 66e42'52 11 , Bydrologic Unit 21010002 on right bank at abandoned power house at Charco Hondo, 1.5 M! (2.4 km) upstream from mouth, and 4 mi (6 km) couth of Arecibo. DRAINAGE ARBA.—57.6 mi* (149.2 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—April 1969 to June 1971, October 1981 to current year. GAQB.—Water-stage recorder and crest-stage gage. Elevation of gage is 60 ft (18 m), from topographic map. REMARKS.—Records poor. Diversion 0.8 mi (1.3 km) upstream for municipal supply of Arecibo. AVERAGE DISCHARGE.--11 years (1969-71, 1981-91), 88.2 ftVs (2.498 m'/s), 20.79 in/yr (528 mm/yr), 63,900 acre-ft/yr (78.8 hmVyr); median of yearly mean discharges, 86 ftVs (2.44 m'/s), 62,300 acre-ft/yr (77 hmVyr) . EXTREMES FOR PERIOD OF RBCORD.—Maximum discharge, 15,000 ftVs (425 m'/s). May 18, 1985, gage height, 17.95 ft (5.471 m), from floodmark, from rating curve extended above 1,000 ft'/s (28.3 m'/s) on basis of step-backwater analysis} minimum discharge, 3.3 ftVs (0.093 m'/s). May 28, 29, 1989. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 2,000 ft'/s (56.6 m'/s) and maximum (*)t Date Oct. 1 Apr. 25 May 5 Time 1830 2015 2000 Discharge (ftVs) (mVs) *7,811 2,020 3,261 221 57.2 92.4 Gage height (ft) (m) *15.36 10.16 11.71 4.682 3.097 3.569 Date May 10 July 8 Time 1945 1830 Discharge (ftVs) (mVs) 3,010 2,282 85.2 64.6 Gage (ft) 11.42 10.52 height (M) 3.481 3.206 Minimum daily discharge, 35 ftVs (0.991 m'/s), Apr. 22. DISCHARGE, CUBIC FEET PBR SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUQ SBP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC -FT CFSM IN. CAL YR WTR YR 550 e360 e300 e250 e225 el90 e350 e!90 e205 e!70 e!30 124 143 309 328 380 479 465 562 316 430 312 237 212 255 357 233 191 170 154 152 8729 282 562 124 17310 4.89 5.64 1990 1991 159 e!45 e!40 e!40 el65 elSO el45 145 e!21 el!8 e!21 el22 el 15 ellO e!09 e!03 elOO el 10 el06 e!04 e!07 e!06 e99 e98 e95 e88 e83 e81 e78 e77 —— 3440 115 165 77 6820 1.99 2.22 TOTAL 30865 TOTAL 38500 e96 e82 e78 e77 e75 e73 e72 e68 e70 e66 e69 e72 e65 e64 e63 e61 e60 e60 e61 e64 e61 e58 e57 e54 e54 e53 e53 eSl e78 e67 e60 2042 65.9 96 51 4050 1.14 1.32 MEAN MEAN e53 e53 eSO e52 e52 eSO eSO 49 50 49 49 48 48 47 47 46 46 45 44 44 44 44 44 43 43 43 42 42 42 41 41 1441 46.5 53 41 2860 .81 .93 84.6 MAX 105 MAX 44 42 42 56 123 174 58 50 47 48 72 57 69 54 48 46 45 46 72 150 74 51 47 47 45 44 43 42 --- 1736 62.0 174 42 3440 1.08 1.12 562 MIN 562 MIN 44 42 41 41 40 40 40 40 40 39 41 43 41 40 39 38 38 40 39 37 38 46 55 41 38 65 130 53 44 41 40 1394 45.0 130 37 2760 .78 .90 13 AC-FT 35 AC-FT 39 44 72 81 128 52 45 42 42 40 39 44 40 38 48 92 43 39 38 36 36 35 35 36 310 336 97 e60 e38 e38 —— 2063 68.8 336 35 4090 1.19 1.33 61220 76360 66 104 92 148 479 e250 e90 e80 e!80 430 305 e230 e270 e!80 el40 ellO elOO el 10 e!20 342 352 e86 e80 e80 e80 e76 e74 e72 e70 e70 e68 4934 159 479 66 9790 2.76 3.19 CFSM 1.47 CFSM 1.83 e66 e63 e59 e58 e57 e55 e53 50 55 57 61 64 66 77 117 124 68 132 99 110 136 111 72 75 64 60 66 116 100 183 —— 2474 82.5 183 50 4910 1.43 1.60 IN. 19.93 IN. 24.86 140 79 69 63 63 58 156 338 306 103 83 e74 e72 70 81 168 231 151 101 e90 e74 e85 84 84 82 82 82 e78 92 82 e74 3395 110 338 58 6730 1.90 2.19 122 99 84 83 202 133 101 99 e90 e84 e78 e74 elOO e74 e!03 e90 e!02 e74 e68 e72 249 432 287 132 e74 105 152 257 112 87 e70 3889 125 432 68 7710 2.18 2.51 278 180 112 81 69 65 73 88 68 72 71 75 95 69 67 70 91 71 65 89 130 108 77 70 82 87 145 210 125 80 —— 2963 98.8 278 65 5880 1.71 1.91 Estimated RIO GRANDS DB ARBCZBO BASIN 50029000 RIO GRANDS DB ARBCIBO AT CENTRAL CAMBAIACHB, PR WATER-QUALITY RECORDS LOCATION.--Lat 18»27'20", long 66°12'10", Hydrologic Unit 21010002, at bridge on unimproved (152 m) upstream from Central Cambalache, near Highway 2, 8.3 mi (13.4 km) downstream frc 1.9 mi (3.1 km) downstream from Rio Tanam» , and 1.6 ml (2.6 km) southeast of Arecibo. DRAINAGE ARBA.--200 mi* (520 km*), approximately. PERIOD OF RECORD.—Water years 1963-66, 1969 to current year. WATER-QUALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 83 road, about 500 ft m Dos Boeas Reservoir, DATB NOV 1990 01... JAN 1991 14... FBB 26... APR 15... JUN 25... AUG 21... TIME 1330 1000 1115 1015 0845 1130 DIS- CHARGE, INST. CUBIC FEET PER SECOND 1200 75 108 172 117 241 SPE- CIFIC CON- DUCT- ANCE (US/CM) 248 250 300 250 284 262 PH (STAND- ARD UNITS) 7.6 7.9 8.1 7.5 7.8 7.8 TEMPER- ATURE WATER (DBG C) 26.5 23.0 25.0 25.0 26.0 25.5 TUR- BID- ITY (NTU) 42 3.5 3.7 2.0 6.3 100 OXYGEN, DIS- SOLVED (MG/L) 6.2 7.3 8.8 7.9 7.5 7.1 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 77 83 104 94 90 385 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 15 <10 <10 10 <10 24 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K1500 380 200 360 5000 20000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K1200 K40 Kl K100 300 10000 DATB NOV 1990 01... JAN 1991 14... FBB 26... APR 15... JUN 25... AUG 21... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH NAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CACO3) CACO3 110 110 120 34 34 40 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L AS CA) AS MG) AS NA) 5.5 10 SODIUM AD- SORP- TION (MG/L RATIO ALKA- POTAS- UNITY SIUM, MAT WH DIS- TOT FBT SULFIDE SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.4 2.3 5.7 9.3 0.4 1.8 4.5 7.1 0.3 1.9 CACO3 95 120 100 120 110 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L <0.5 12 <0.5 12 (MG/L AS S) AS SO4) AS CL) 6.0 11 10 6.8 SOLIDS, RESIDUE DATB NOV 1990 01... JAN 1991 14... FBB 26... APR 15... JUN 25... AUO 21... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- <0.10 — <0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 18 — — 16 — 12 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 152 — — 149 -- 144 SOLIDS, DIS- SOLVED (TONS PER DAY) 493 — — 69.1 — 93.9 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 43 50 <1 <1 16 111 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.870 — — 0.350 — 0.500 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.030 <0.010 <0.010 0.010 <0.010 0.030 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.900 0.600 0.500 0.360 0.420 0.530 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.100 0.020 0.030 0.040 0.090 0.030 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.60 0.18 — 0.36 1.1 0.37 non-ideal count 84 RIO ORANDB DB ARBCIBO BASIN 50029000 RIO GRANDE DB ARBCIBO AT CENTRAL CAMBALACHB, PR--Continued MATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 01... JAN 1991 14... FBB 26... APR 15... JUN 25... AUG 21... DATE NOV 1990 01... JAN 1991 14... FBB 26... APR 15... JUN 25... AUG 21... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.70 0.20 <0.20 0.40 1.2 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.6 0.80 — 0.76 1.6 0.93 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 7.1 3.5 — 3.4 7.2 4.1 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.070 0.020 0.020 0.030 0.070 0.090 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 — — <1 — — SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — ~ SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 — — <10 -- — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — ~ CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 5 — — <1 — — PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) 20 — — 10 — ~ MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 3300 180 <1 200 20 <0.10 <0.10 <1 <1 <1 <1 20 <0.010 <0.010 <1 0.03 0.01 PESTICIDE ANALYSES DATE JUN 1991 25... DATE JUN 1991 25... TIME 0845 IDRIN, •OTAL :UG/L) PCS, TOTAL (UG/L) <0.1 BTHION, TOTAL (UG/L) ALDRIN, TOTAL (UG/L) <0.010 HBPTA- CHLOR, TOTAL (UG/L) CHLOR- DANB, TOTAL (UG/L) <0.1 HBPTA- CHLOR EPOXIDB TOTAL (UG/L) ODD, TOTAL (UG/L) <0.010 LINDANB TOTAL (UG/L) DDE, TOTAL (UG/L) <0.010 MALA- THION, TOTAL (UG/L) DOT, TOTAL (UG/L) <0.010 MBTH- OXY- CHLOR, TOTAL (UG/L) DI- AZINON, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) DI- BLDRIN TOTAL (UG/L) <0.010 METHYL TRI- THION, TOTAL (UG/L) BNDO- SULFAN, TOTAL (UG/L) <0.010 MI REX, TOTAL (UG/L) <0.010 <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 <0.01 ',^ 0355 035950 *T\ EXPLANATION SURFACE-WATER STATION AND NUMBER V°3°7 QUALITY-OF-WATER STATION AND NUMBER WELL AND WELL NUMBER 032290 LAKE-ELEVATION STATION 0123456 KILOMETERS j__L_L—J,_L_j__L_. 1 i I" i I 01234 MILES Figure 15.-Rfo Grande de Manati basin. 86 RIO GRANDE DB MANATI BASIN 50030700 RIO OROCOVIS NEAR OROCOVI8, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°14'20-, long 66022'58", at flat low bridge about 300 ft (91 M) northwest of Highway (1.6 k») north of Orocovis plaza. DRAINAGE AREA.—10.1 mi2 (26.2 k*1 ) . PERIOD OF RECORD.—Hater year 1979 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 568, 1.0 mi DATE OCT 1990 24... DEC 05... FEB 1991 06... APR 03... JUN 20... AUQ 16... TIME 1230 1330 1245 .1300 1215 1045 DIS- CHARGE, IN8T. CUBIC FEET PER SECOND 27 20 10 6.8 5.2 6.5 SPE- CIFIC CON- DUCT- ANCE (US/Of) 206 252 292 314 332 309 PH (STAND- ARD UNITS) 8.1 8.3 8.2 8.5 8.1 8.2 TEMPER- ATURE WATER (DBG C) 23.5 22.5 21.0 23.5 25.5 23.5 TUR- BID- ITY (NTU) 10 25 65 1.5 1.7 20 OXYGEN, DIS- SOLVED (MG/L) 7.8 8.3 9.0 9.1 8.0 8.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 95 99 104 108 101 97 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 14 19 18 <10 <10 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 4300 4900 4300 K30 470 4200 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K660 K100 2000 K150 360 780 DATE OCT 1990 24... DEC 05... FEB 1991 06... APR 03... JUN 20... AUG 16... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL NH WAT DI8- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CACO3 80 130 130 19 33 32 MAGNE- SIUM, SODIUM, DI8- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MO) AS NA) SODIUM AD- SORP- TION RATIO 12 14 11 13 ALKA- POTA8- LINITY 8IUM, WAT WH DI8- TOT PET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MQ/L AS K) 7.8 9.6 0.5 1.8 0.5 1.8 0.5 1.7 CAC03 75 96 110 120 140 120 CHLO- SULFATB RIDE, DI8- DIS- SOLVED SOLVED (MG/L (MG/L AS 8) AS 804) AS CL) <0.5 7.9 14 <0.5 11 16 10 16 SOLIDS, RESIDUE DATE OCT 1990 24... DEC 05... FBB 1991 06... APR 03... JUN 20... AUG 16... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- — <0.10 — 0.10 SILICA, DIS- SOLVED (MG/L AS 8102) 28 — — 33 — 32 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 133 — — 193 — 188 SOLIDS, DIS- SOLVED (TONS PER DAY) 9.69 — — 3.54 __ 3.31 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 23 164 96 2 5 3 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.880 — 1.29 _ _ 1.09 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 <0.010 0.010 <0.010 <0.010 0.010 NITRO- GEN, NO2+N03 TOTAL (MG/L AS N) 0.900 0.800 1.30 0.590 0.930 1.10 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.050 0.010 0.040 0.040 0.020 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.28 0.45 0.49 — 0.26 0.18 non-ideal count 87 RIO GRANDE DK MANATI BASIN 50030700 RIO OROCOVIS NEAR OROCOVI8, PR—Continued MATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 24... DEC 05... FEE 1991 06... APR 03... OUN 20... AUG 16... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0,30 0.50 0.50 <0.20 0.30 0.20 NITRO- GEN, TOTAL (MQ/L AS N) 1.2 1.3 1.8 — 1.2 1.3 NITRO- GEN, TOTAL (MG/L AS NO3) 5.3 5.8 8.0 -- 5.4 5.8 PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.090 <1 0.210 0.230 0.260 <1 0.170 0.200 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 — — <100 — — CHRO- BORON, CADMIUM MIUM, COPPER, TOTAL TOTAL TOTAL TOTAL RBCOV- RECOV- RBCOV- RECOV- ERABLE BRABLE ERABLB BRABLE (UG/L (UG/L (UG/L (UG/L AS B) AS CD) AS CR) AS CO) <10 <1 4 10 __ __ <10 <1 <1 10 __ — DATE OCT 1990 24... DEC 05... PEE 1991 06... APR 03... JUN 20... AUG 16... IRON, TOTAL RECOV- ERABLE (UG/L AS PB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 1100 110 60 20 <0.10 <0.10 10 <0.010 <0.010 0.02 0.02 88 RIO ORANDB 08 MANATI BASIN 50031200 RIO ORANDB DB MANATI NEAR MOROVI8, PR LOCATION.--Lat 18°17'45 B , long 66«24'47", Hydrologic Unit 21010001, on right bank , 0.1 mi (0.2 km) downstream from Quebrada Perchas, 0.8 mi (1.3 km) upstream from Rio Sana Muerto, and 2.2 mi (3.5 km) south of Morovis. DRAINAQB ARBA.--55.2 mi* (143.0km*). WATER-DISCHARGE RECORDS PERIOD OF RBCORD.—January 1965 to current year. QAQB.—Water-stage recorder and concrete control. Elevation of gage ia 440 ft (134 m), from topographic map. Feb. 2, 1966 to Apr. 27, 1967, staff gage read twice daily. REMARKS.—Records fair. Public water-supply pumpage, about 300 ft (91 m) above the station, influences low-flow discharges. Oage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--26 years (1966-91), 101 ft*/s (2.860 mV»), 24.85 in/yr (631 mm/yr), 73,170 acre-ft/yr (90.2 hmVyr); median of yearly mean discharges, 88 ft5/" (2.49 mVs), 63,700 acre-ft/yr (78 hmVyr). EXTREMES FOR PERIOD OF RBCORD.--Maximum discharge, 48,000 fta/s (1,359 m5/»). May 18, 1985, gage height, 17.89 ft (5.453 m), from floodmarks, from rating curve extended above 200 fts/s (5.66 mVs) on basis of computations of flow over broad-crested weir and step-backwater analysis; -»<"*••"• discharge, 4.4 fts/s (0.125 m'/s). Apr. 15, 1984. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 3,500 ft5/" (99.1 mVs) and maximum (*)« Time Discharge (fts/s) (mVs) Gage height (ft) (m) Date Discharge (fts/») (m'/s) Date Time Oct. 15 1540 *2,920 82.7 *4.65 1.417 Minimum discharge, 15 fta/s (0.425 m'/s), Sept. 6, 7. DISCHARGE, CUBIC FEET PBR SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES Qage height (ft) (m) DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL ADO SBP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 . TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 164 89 51 104 106 92 244 157 219 226 161 105 107 565 629 638 4S4 380 5*9 29f 781 31C 204 169 237 446 226 170 150 134 132 8263 267 781 51 16390 4.83 5.57 1990 1991 117 109 102 120 127 103 94 100 89 80 76 73 C9 68 «4 75n cs Cl 1M 131 ICO 135 96 79 74 91 99 73 120 —— 2858 95.3 160 61 5670 1.73 1.93 TOTAL 27347 TOTAL 29100 92 101 275 201 125 100 85 75 72 73 67 84 94 66 92 95 67 61 59 5C 55 57 64 66 58 50 50 50 51 98 187 2726 87.9 275 50 5410 1.59 1.84 MEAN MEAN 194 131 102 82 83 111 95 76 76 82 79 67 62 57 53 53 50 48 47 46 45 43 44 43 41 42 40 40 39 40 40 2051 66.2 194 39 4070 1.20 1.38 74.9 MAX 79.7 MAX 47 41 42 51 61 144 106 61 45 44 83 64 155 87 61 54 115 129 280 161 122 93 75 67 59 57 54 48 —— 2406 85.9 280 41 4770 1.56 1.62 781 MIN 12 781 MIN 15 48 45 46 45 45 45 45 48 47 44 45 48 44 45 42 40 40 49 47 41 42 168 145 74 55 129 208 103 68 56 49 1996 64.4 208 40 3960 1.17 1.35 AC-FT AC-FT 48 47 58 53 49 42 44 54 72 45 46 56 114 63 61 55 46 41 39 38 37 37 35 34 34 34 31 31 30 47 1421 47.4 114 30 2820 .86 .96 54240 57720 85 89 137 104 53 37 59 93 55 41 35 120 358 501 233 121 82 65 61 58 46 41 38 35 35 35 36 32 30 29 45 2789 90.0 501 29 5530 1.63 1.88 CFSM 1.36 CFSM 1.44 49 33 30 28 30 29 30 29 28 28 28 28 28 28 28 27 27 28 29 29 29 42 32 36 30 28 27 26 26 35 —— 905 30.2 49 26 1800 .55 .61 IN. 18.43 IN. 19.61 37 29 25 24 23 22 24 43 92 33 25 23 21 19 28 605 177 82 52 42 34 30 29 28 27 25 25 44 52 30 28 1778 57.4 605 19 3530 1.04 1.20 25 24 23 21 21 21 20 20 20 20 21 20 21 19 45 28 24 32 23 20 22 24 69 29 23 21 82 109 39 26 22 934 30.1 109 19 1850 .55 .63 20 20 20 18 16 15 103 107 39 32 23 49 54 28 21 24 23 34 23 31 45 26 25 26 21 19 18 43 24 26 973 32.4 107 15 1930 .59 .66 89 RIO ORAMDB DE MANATI BASIN 50031200 RIO GRANDB DB MANATI NEAR MOROVIS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water year* 1968 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 24... DEC 05... FBB 1991 06... APR 03... JUN 20... ADG 16... TIME 0930 1110 1000 1000 0945 0815 DIS- CHARGE, INST. CUBIC FEET PER SECOND 169 123 118 44 29 27 SPE- CIFIC CON- DUCT- ANCE (US/CM) 221 231 234 281 281 287 PH (STAND- ARD UNITS) 8.0 8.2 8.0 8.2 8.6 7.9 TEMPER- ATURE WATER (DBG C) 23.5 22.5 20.5 23.0 26.5 25.5 TUR- BID- ITY (NTU) 11 70 98 5.0 2.4 6.4 OXYGEN, DIS- SOLVED (MG/L) 8.5 8.4 8.7 8.4 8.2 7.2 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 101 96 96 97 105 87 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 16 16 31 <10 13 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K1200 K1200 6000 110 80 K1600 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 530 650 11000 92 K51 220 DATS OCT 1990 24... DEC 05... FBB 1991 06... APR 03... JUN 20... AUG 16... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS CACO3) CAC03 85 120 110 MG/L AS (MG/L 20 MAGNB- SODIUM SIUM, SODIUM, AD- DIS- DIS- SORP- DIS- TOT FBT SULFIDB SOLVED SOLVED TION SOLVED FIELD TOTAL ALKA- POTAS- LINITY SI0M, WAT WH (MG/L 28 11 27 10 (MG/L AS CA) AS MG) AS NA) 8.5 11 13 13 RATIO (MG/L MG/L AS (MG/L AS K) 0.5 2.3 0.5 1.9 0.5 2.2 CACO3 78 84 92 110 105 110 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) <0.5 11 14 <0.5 7.5 6.3 8.1 16 SOLIDS, RESIDUE DATE OCT 1990 24... DEC 05... FBB 1991 06... APR 03... JUN 20... AUG 16... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 2.6 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 27 — — 28 — 27 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 141 -- -- 164 -- 169 SOLIDS, DIS- SOLVED (TONS PER DAY) 64.2 — — 19.6 — 12.2 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 24 113 172 10 26 3 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.08 0.790 0.870 0.380 0.140 0.310 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.010 0.030 0.010 0.040 0.020 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.10 0.800 0.900 0.390 0.180 0.330 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.020 0.030 0.030 0.030 0.040 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.28 0.28 0.97 0.17 — 0.26 non-ideal count 90 RIO QRANDB DE MANATI BASIN 50031200 RIO GRANDS DB MANATI NEAR MOROVIS, PR--Continued MATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTMBER 1991 DATE OCT 1990 24... DEC 05... FBB 1991 06... APR 03... JUN 20... AUG 16... DATE OCT 1990 24... DEC 05... FEB 1991 06... APR 03... JUN 20... AUG 16... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.30 1.0 0.20 <0.20 0.30 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 1.4 1.1 1.9 0.59 — 0.63 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 6.2 4.9 8.4 2.6 — 2.8 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.070 0.090 0.140 0.060 0.040 0.080 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 — — <1 — -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 — -- <100 ~ — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 30 ~ ~ 30 — -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 ~ ~ <1 -- — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 3 — ~ 2 ~ ~ PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) 10 — ~ <10 -- ~ MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1200 610 60 30 <0.10 <0.10 10 <0.010 <0.010 0.03 0.01 RIO ORANDB DB MANATI BASIN 91 50032290 IJUJO EX. OOINBO AT DAMSITB, PR LOCATION.—Lat 18«09'41-, long 66°51'48", Hydrologic Unit 21010001, at davit* on Rio Tore Nagro, 3.0 mi (4.8 km) northwest from Villalba plaxa and 1.9 mi (3.1 km) northeast of Cerro Maravillas. The reservoir itself fix** the territorial limit* between the Municipality of Ciales and Orocovis. DRAINAQB ARBA.~1.64 mi* (4.25 km1 ). PERIOD OF RECORD.--May 1988 to current year. ELEVATION RECORDS QAQB.—Water stage recorder. Datum of gage is mean sea level. REMARKS.—Lago Quineo was completed in 1931. It provide! a »«-iri»«« storage of approximately 2,180 ac-ft (2.688 hm*) for power and irrigation. Water* are discharged through an outlet power tunnel into the Rio Tore Negro and coveyed to the head water work* of Tore Negro Hydroelectric Plant No.2, for energy generation at Tore Negro Hydroelectric plant No.l, and are discharged into the Ouayabal Reservoir to be later used for irrigation at South Coast Irrigation System. The dam is rockfill with a vertical concrete corewall, rock toes, and riprap facing of upstream slope, with a total length of 565 ft (172 m), a maximum structural height of 125 ft (38 m) to top of corewall. At a maximum reservoir water surface elevation the uncontrolled morning-glory tunnel spillway crest has an elevation of 2,966 ft (904 m) above mean sea level and a design capacity of 7,000 ftV«. The dam is owned by Puerto Rico Electric Power Authority. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.—Maximum elevation 2,961.70 ft (902.73 m), Oct. 21, 1990; minimun elevation, 2,919.79 ft (899.95 m), May 27, 1988. EXTREMES FOR CURRENT TEAR.—Maximum elevation, 2,961.70 ft (902.73 m), Oct. 21; minimun elevation, 2,945.53 ft (897.80 m), Oct. 1. Capacity Table (based on data from Puerto Rico Electric Power Authority) Elevation, in feet 2,872 2,919 2,925 Contents, in acre-feet 0 361 491 Elevation, in feet 2,943 2,950 2,961 Contents, in acre-feet 1,029 1,308 1,852 DAY ELEVATION (FEET NOVD), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY OBSERVATION AT 24100 VALUES OCT NOV DBC JAN FBB MAR APR MAY JDN JOL AUO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX KIN 2946.21 2949.32 2949.89 2950.25 2950.43 2950.67 2950.88 2950.93 2951.85 2952.77 2952.89 2953.77 2954.64 2955.46 2956.08 2959.51 2960.18 2960.95 2960.81 2960.66 2960.89 2960.78 2960.26 2960.75 2961.00 2960.85 2960.87 2960.91 2960.65 2960.85 2960.37 2956.33 2961.00 2946.21 2960.72 2960.71 2960.31 2960.77 2960.34 2959.89 2959.38 2958.81 2959.01 2959.27 2959.53 2959.77 2959.51 2959.72 2959.40 2959.05 2958.84 2959.05 2959.73 2960.16 2960.34 2960.62 2960.76 2960.70 2960.69 2960.55 2960.47 2960.36 2960.18 2959.80 2959.95 2960.77 2958.81 2959.98 2960.22 2960.06 2959.82 2959.69 2959.61 2959.48 2959.16 2959.31 2959.44 2959.37 2959.53 2959.00 2958.90 2958.49 2958.63 2958.36 2958.20 2957.87 2957.58 2957.70 2957.79 2957.89 2957.78 2957.64 2957.43 2957.07 2956.55 2956.43 2956.54 2956.55 2958.45 2960.22 2956.43 2956.44 2956.20 2955.98 2955.80 2955.88 2955.98 2956.06 2956.16 2956.26 2956.30 2956.06 2956.11 2956.18 2955.98 2955.89 2955.66 2955.55 2955.38 2954.98 2955.04 2954.42 2954.00 2953.60 2953.42 2953.10 2952.45 2952.51 2952.56 2952.14 2951.74 2951.60 2954.82 2956.44 2951.60 2951.43 2951.50 2951.62 2952.19 2952.15 2952.08 2952.06 2952.14 2952.22 2952.43 2952.04 2951.66 2951.78 2951.89 2951.95 2952.05 2952.13 2952.24 2951.83 2951.91 2951.98 2952.03 2952.09 2952.17 2952.25 2952.31 2952.37 2952.44 2952.03 2952.44 2951.43 2952.50 2952.55 2952.60 2952.67 2952.73 2952.58 2952.63 2952.18 2952.23 2952.27 2952.34 2952.40 2952.43 2952.47 2952.51 2952.52 2952.57 2952.44 2952.50 2952.53 2952.59 2952.77 2952.81 2952.87 2952.91 2955.01, 2955.11 2955.20 2955.26 2955.32 2955.37 2953.06 2955.37 2952.18 2955.42 2955.32 2955.40 2955.34 2955.45 2955.53 2955.59 2955.67 2955.49 2955.43 2955.37 2954.87 2954.93 2954.98 2954.26 2953.68 2952.90 2952.30 2951.32 2950.40 2950.48 2950.21 2949.64 2949.42 2949.46 2949.52 2949.02 2949.06 2949.10 2949.28 2952.83 2955.67 2949.02 2948.82 2948.92 2948.98 2949.34 2949.44 2949.03 2949.09 2949.05 2949.11 2949.23 2949.83 2949.94 2950.09 2950.18 2949.89 2949.95 2950.03 2950.13 2950.22 2952.24 2952.26 2952.41 2952.28 2952.15 2952.27 2952.33 2952.41 2951.85 2951.91 2951.96 2952.01 2950.56 2952.41 2948.82 2952.13 2952.33 2952.17 2951.97 2951.25 2950.67 2950.47 2950.53 2950.59 2950.01 2949.83 2949.93 2949.97 2949.67 2949.72 2949.75 2949.79 2949.96 2950.42 2950.11 2950.57 2950.71 2950.79 2950.85 2950.93 2950.97 2951.03 2951.09 2950.99 2952.45 2950.72 2952.45 2949.67 2952.44 2952.07 2951.77 2951.86 2951.63 2951.69 2952.25 2954.71 2954.71 2954.53 2954.35 2954.45 2954.55 2954.63 2954.93 2957.91 2957.73 2957.87 2957.43 2956.97 2957.13 2957.07 2956.73 2956.45 2956.58 2956.43 2955.81 2956.21 2955.79 2955.89 2955.78 2955.11 2957.91 2951.63 2955.44 2954.84 2954.92 2955.02 2954.90 2954.56 2954.64 2954.40 2954.46 2954.54 2954.60 2954.46 2954.39 2954.67 2954.09 2954.65 2954.05 2953.47 2953.05 2953.35 2953.75 2954.89 2954.75 2954.95 2955.17 2954.81 2954.35 2954.10 2953.57 2953.30 2953.42 2954.37 2955.44 2953.05 2953.64 2953.78 2953.04 2952.48 2952.18 2951.94 2952.04 2952.14 2952.05 2951.55 2951.63 2951.24 2951.21 2951.29 2951.37 2951.09 2950.87 2950.57 2950.44 2950.39 2950.51 2950.61 2950.35 2950.05 2949.73 2949.79 2949.65 2949.95 2950.06 2949.76 2951.18 2953.78 2949.65 CAL YR 1990 WTR YR 1991 MEAN 2937. MEAN 2954. MAX 2961.00 MIN 2926.24 MAX 2961.00 MIN 2946.21 92 RIO ORANDB DB MANATI BASIN 50032590 LAOO DB MATRULLA8 AT DAMSITE, PR LOCATION. —Lat 18«12'4«", long «««28'50-, Hydrologic Unit 21010001, in concrete house at damsite, and 5.8 mi (9.3 km) southwest of Orocovis. DRAINAOB AREA. --4. 46 mi* (11.55 In*). BLBVATION RECORDS PBRIOD OP RBCORD.— May 1988 to current year. OAQB. — Water- stag* recorder. Datum of gag* is mean sea level. REMARKS.-- Lago Matrullas was completed in 1934. The dam is an earthfill structure about 120 ft ( 37 m) height, a top width of 30 ft (9 m) and a length of 710 ft (216 m) , and has a ma-Hami storage capacity of about 4,274 ac-Ct (5.220 hm*) at top of dam elevation. The Matrullas Dam is owned by the Puerto Rico Electric Power Authority and im part of the Toro Negro Hydroelectric Project; a project developed by the P.R.B.P.A. Cor the primary purpose of generating electric power. Di •charge* from the Power Plant* are collected by the Jacaguas River which Clows into Ouayabal Dam, at which dam they are regulated Cor irrigation oC land* served by the Juana D£az Canal. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PBRIOD OP RECORD.— Maximum elevation 2,413.49 Ct (735.63 m) , Sept. 30, 1989; minimum elevation 2,392.81 Ct (729.33 m), Sept. 10, 1989. EXTREMES OBSERVED POR CURRENT YEAR. —Maximum elevation, 2,413.15 Ct (735.53 m), Mar. 26; minimum elevation 2,409.56 ft (734.43 m), Aug. 16. Capacity Table (based on data from Puerto Rico Electric Power Authority) Elevation, in Ceet 2,338 2,3CO Contents, in acre-feet 2 302 Elevation, in Ceet 2,399 2,415 Contents, in acre-feet 1,845 2,945 DAY ELEVATION (PEBT NOVD), WATBR YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY OBSERVATION AT 24iOO VALUES OCT NOV DEC JAN PBB MAR APR MAY JUN JUL AUQ SEP 1 2412.14 2 2411.68 3 2411.69 4 2411.76 5 2411.82 6 2412.03 7 2412.26 8 2412.26 9 2412.53 10 2412.47 11 2412.08 12 2412.13 13 2412.45 14 2412.46 15 2412.52 16 2412.44 17 2412.23 18 2412.33 19 2412.39 20 2412.34 21 2412.88 22 2412.55 23 2412.43 24 2412.51 25 2412.69 26 2412.77 27 2412.67 28 2412.73 29 2412.59 30 2412.53 31 2412.39 TOTAL74782.75 MEAN 2412.35 MAX 2412.88 KIN 2411.68 CAL YR 1990 WTR YR 1991 2412.28 2412.57 2412.53 2412.83 2412.63 2412.60 2412.58 2412.58 2412.66 2412.51 2412.67 2412.70 2412.55 2412.46 2412.24 2412.12 2412.02 2412.24 2412.55 2413.06 2412.74 2412.86 2412.73 2412.70 2412.68 2412.52 2412.46 2412.38 2412.32 2412.32 --- 72376.09 2412.54 2413.06 2412.02 2412.61 2412.71 2412.65 2412.60 2412.55 2412.55 2412.55 2412.41 2412.61 2412.67 2412.67 2412.67 2412.67 2412.52 2412.45 2412.62 2412.48 2412.41 2412.35 2412.29 2412.51 2412.63 2412.65 2412.65 2412.65 2412.42 2412.23 2412.09 2412.10 2412.35 2412.66 74787.98 2412.51 2412.71 2412.09 2412.65 2412.42 2412.25 2412.16 2412.33 2412.54 2412.59 2412.35 2412.22 2412.27 2412.45 2412.55 2412.57 2412.32 2412.32 2412.15 2412.12 2412.17 2412.15 2412.23 2412.07 2411.85 2411.69 2411.52 2411.34 2411.03 2411.03 2411.07 2410.89 2410.63 2410.47 74770.40 2411.95 2412.65 2410.47 TOTAL 878922.73 MEAN 2408. TOTAL 880268.10 MEAN 2411. 2410.33 2410.41 2410.57 2410.51 2410.50 2410.53 2410.57 2410.59 2410.71 2410.96 2410.93 2410.75 2410.77 2410.82 2410.85 2410.98 2411.12 2411.31 2411.17 2411.10 2411.09 2411.07 2411.17 2411.30 2411.35 2411.33 2411.31 2411.29 —— —— 67505.39 2410.91 2411.35 2410.33 2411.29 2411.38 2411.49 2411.51 2411.51 2411.47 2411.44 2411.21 2411.21 2411.30 2411.31 2411.27 2411.25 2411.22 2411.17 2411.24 2411.33 2411.37 2411.37 2411.35 2411.37 2411.93 2412.21 2412.33 2412.13 2413.15 2412.52 2412.47 2412.45 2412.43 2412.44 74762.12 2411.68 2413.15 2411.17 2412.44 2412.47 2412.63 2412.70 2412.51 2412.49 2412.49 2412.47 2412.45 2412.35 2412.27 2412.07 2412.16 2412.28 2412.13 2412.07 2411.77 2411.44 2411.42 2411.53 2411.67 2411.82 2411.90 2411.96 2411.91 2411.87 2411.63 2411.62 2411.59 2411.82 —— 72361.93 2412.06 2412.70 2411.42 01 MAX 2413.06 KIN 2403. 69 MAX 2413.15 KIN 2409. 2412.51 2412.40 2412.37 2412.51 2412.39 2412.07 2411.98 2411.91 2411.89 2411.92 2412.05 2412.18 2412.25 2412.21 2412.03 2411.93 2411.91 2412.03 2412.16 2412.99 2412.42 2412.25 2412.20 2412.18 2412.26 2412.25 2412.25 2412.03 2411.97 2411.93 2411.93 74777.36 2412.17 2412.99 241i:89 11 64 2412.05 2412.17 2412.12 2412.09 2411.85 2411.57 2411.42 2411.49 2411.61 2411.39 2411.13 2411.09 2411.05 2410.89 2410.91 2411.00 2410.97 2410.95 2410.85 2410.67 2410.57 2410.65 2410.75 2410.73 2410.68 2410.61 2410.56 2410.51 2410.46 2411.82 —— 72334.61 2411.15 2412.17 2410.46 2411.98 2411.83 2411.62 2411.63 2411.46 2411.49 2411.58 2411.77 2412.01 2412.05 2412.06 2412.07 2412.05 2412.07 2412.09 2412.76 2412.15 2411.93 2411.68 2411.31 2411.31 2411.29 2411.05 2410.81 2410.85 2410.84 2410.56 2410.72 2410.69 2410.61 2410.55 74756.87 2411.51 2412.76 2410.55 2410.39 2410.11 2410.10 2410.22 2410.21 2410.02 2409.91 2409.83 2409.75 2409.81 2409.90 2409.86 2409.81 2409.79 2409.64 2410.07 2410.27 2409.99 2409.73 2409.64 2410.36 2411.68 2411.89 2411.90 2412.00 2411.77 2411.52 2411.25 2410.95 2410.69 2410.71 74723.77 2410.44 2412.00 2409.64 2412.04 2412.15 2412.05 2412.03 2411.81 2411.86 2411.98 2411.99 2411.91 2411.74 2411.69 2411.46 2411.25 2411.01 2411.04 2410.89 2410.67 2410.45 2410.19 2410.05 2410.13 2410.26 2410.17 2409.99 2409.77 2409.68 2409.87 2410.17 2410.32 2410.21 —— 72328.83 2410.96 2412.15 2409.68 RIO ORAKDB DB MANATI BASIN 93 50034000 RIO BAUTA NEAR OROCOVI8, PR LOCATION.—Lat 18«14'10", long 66«27'18", Bydrologlc Unit 21010001, on left bank, at bridge on Highway 157 (12.1 km), and 4.2 mi (€.8 km) west of Orocovis. DRAINAGE ARBA.--16.7 mi* (43.3 km*). WATER-DISCHARGE RECORDS PERIOD OF RBCORD.—February 1959 to April 1966 (annual low-flow measurement! only), February to September 1969 (occasional measurements only), October 1969 to September 1982, October 1988 to current year. GAGE.—Water-stage recorder and crest-stage gage. Datum of gage is 772.82 ft (235.556 m) above mean sea level. REMARKS.--Records fair. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--IS years (1971-82,1989-91), 36.0 fts/s (1.020 mVs), 29.27 in/yr (743 mm/yr), 26,080 acre-ft/yr (32.2 hmVyr); median of yearly mean discharges, 28 ftVs (0.79 mVs), 20,300 acre-ft/yr (25 hmVyr). EXTREMES FOR PERIOD OF RBCORD.--Maximum discharge, 17,800 ftVs (504 mVs), Oct. 9, 1970, gage height, 21.9 ft (6.675 m), from floodmark, from rating curve extended above 100 ft3/* (2.83 •?/•) on basis of step-backwater analysis by U.S. Bureau of Reclamation; minimum discharge 2.8 ftVs (0.079 •?/•), July 23, 1977. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 1,500 ft'/s (42.5 •?/•) and marl mum (*)i Discharge Oage height Discharge Gage height Date Time (ftVs) (mVs) (ft) (m) Date Time (ftVs) (mVs) (ft) (m) Oct. 21 1000 1,560 44.2 11.56 3.523 Mar. 26 1645 *1,6SO 46.7 *11.68 3.560 Nov. 20 1620 1,530 43.3 11.52 3.511 Minimum discharge, 6.1 ftVs (0.172 m3/s), July 7. DISCHARGE, CUBIC FRET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DBC JAN FBB MAR APR MAY JDN JUL ATO 8BP 1 60 2 30 3 22 4 21 5 22 6 21 7 27 8 26 9 77 10 120 11 81 12 64 13 143 14 290 IS 271 16 265 17 155 18 160 19 228 20 94 21 542 22 153 23 98 24 98 25 206 26 362 27 189 28 149 29 114 30 85 31 73 TOTAL 4246 MEAN 137 MAX 542 MIN 21 AC-FT 8420 CFSM 8.20 IN. 9.46 CAL YR 1990 WTR YR 1991 60 SO 44 64 49 43 38 33 31 29 27 27 25 24 23 23 22 21 21 239 115 148 90 47 34 29 28 25 23 22 —— 1454 48.5 239 21 2880 2.90 3.24 TOTAL 10140. TOTAL 11439. 21 25 72 52 30 24 21 19 18 18 18 18 17 16 19 17 IS IS 14 14 14 14 IS 14 13 13 13 13 12 14 32 630 20.3 72 12 1250 1.22 1.40 4 MEAN 4 MEAN 25 17 IS 14 13 13 13 13 12 12 12 11 11 11 11 11 11 10 10 10 9.8 9.8 9.8 10 9.9 9.6 9.6 9.5 9.7 9.6 9.7 362.0 11.7 25 9.5 718 .70 .81 27.8 MAX 31.3 MAX 10 9.9 10 9.6 17 36 20 13 11 20 23 22 38 21 IS 14 14 13 21 16 14 12 12 11 12 11 11 11 —— 447.5 16.0 38 9.6 888 .96 1.00 542 MIN 542 MIN 10 9.8 9.9 9.8 10 10 10 9.3 8.9 9.1 9.5 9.7 9.4 9.5 9.1 9.0 9.0 11 9.7 9.2 11 34 22 12 11 268 111 30 19 16 14 739.9 23.9 268 8.9 1470 1.43 1.65 14 14 14 17 16 13 13 13 13 12 12 11 13 11 11 11 10 10 9.8 9.6 9.3 8.9 8.8 8.7 8.6 8.4 8.3 8.1 7.8 11—— 335.3 11.2 17 7.8 665 .67 .75 3.6 AC-FT 20110 6.1 AC-FT 22690 32 23 11 11 9.6 8.2 10 9.8 8.4 8.0 7.7 33 149 85 32 17 12 11 10 91 49 19 14 12 - 11 11 11 10 11 11 11 748.7 24.2 149 7.7 1490 1.45 1.67 CFSM 1. CFSM 1. 11 12 12 11 10 10 10 9.9 9.8 9.4 9.2 9.2 9.2 8.8 8.6 8.5 8.4 8.1 8.0 7.9 7.8 7.9 7.7 7.3 7.2 6.9 6.7 81 7.0 35 365.5 12.2 81 6.7 725 .73 .81 66 IN. 88 IN. 11 7.0 6.6 6.4 6.4 6.2 6.1 69 35 9.5 7.3 6.8 6.6 6.4 6.7 362 69 26 18 14 12 11 11 12 11 10 10 19 18 12 11 823.0 26.5 362 6.1 1630 1.59 1.83 22.59 25.48 9.8 9.6 9.3 27 IS 11 9.2 8.8 8.6 8.4 8.4 8.1 8.3 26 24 13 24 21 13 23 34 122 100 31 19 IS 24 23 14 12 11 690.5 22.3 122 8.1 1370 1.33 1.54 125 77 27 18 14 13 26 24 16 14 13 13 12 11 11 11 13 12 11 13 IS 11 11 11 10 10 14 17 12 12 —— 597 19.9 125 10 1180 1.19 1.33 94 RIO QRANDB DB MANATI BASIN 50034000 RIO BAUTA NBAR OROCOVIS, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.— WATER YEARS OCTOBER 1988 TO CURRENT YEAR STRBAMFLOW, SPECIFIC CON- TEMPERA- STRBAHFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCB TURE DATE TIME INSTANTANEOUS DUCTANCB TURB (CFS) (UMHOS) (DBG C) (CFS) (UMHOS) (DBG C) APR. 30 0845 7.8 210 22.5 JUN. 28 1009 6.9 242 25.0 JUN. 04 1122 11 223 25.5 AUG. 07 1230 9.6 231 27.5 RIO GRANDS DB MANATI BASIN 50035000 RIO QRANDB DB MANATI AT CIALBS, PR 95 LOCATION.—Lat 18«19'26«, long 66«27'36«, Hydrologic Unit 21010001, on left bank, 1.6 mi (2.6 km) upstream from Hwy 145 bridge, 0.8 mi (1.3 km) downstream from Quebrada Saliente, 0.9 mi (1.4 km) upstream from Quebrada Cojo Vales, and 1.2 mi (1.9 km) southeast of Ciales. DRAINAGE ARBA.--128 mi* (332 km*), excludes 6.0 mi* (15.5 km*), the runoff from which is diverted through Bl Guineo and de Matrullas reservoirs. WATER-DISCHARGE RECORDS PERIOD OF RBCORD.—September 1946 to September 1953, May 1956 to December 1957 (unpublished, available in files of Caribbean District Office and in the National Water Data Storage and Retrieval System, Washington, D.C.); February 1959 to September 1960 (monthly discharge measurements only); October 1960 to current year. Equivalent record from January 1971 to December 1972 published as 50035200 Rio Grande de Manati at Highway 145 at Ciales at site 1.6 mi (2.6 km) downstream, drainage area 132 mi 1 (342 km1 ). GAGE.—Water-stage recorder. Elevation of gage is 140 ft (43 m), from topographic map. Prior to Apr. 1, 1962 , staff gage, read twice daily, at site 100 ft (30 m) upstream at same datum. January 1971 to December 1972 at site 1.6 mi (2.6 km) downstream at different datum. REMARKS.—Records poor. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--31 years (1961-91), 258 ft'/s (7.306 m'/s), 27.37 in/yr (695 mm/yr), 186,900 acre-ft/yr (230 hmVyr); median of yearly mean discharges, 232 ftVs (6.57 m'/s), 168,000 acre-ft/yr (207 hmVyr). EXTREMES FOR PERIOD OF RBCORD. - -Maximum discharge, 125,000 ft'/s (3,540 m'/s), Oct. 9, 1970, gage height, 24.0 ft (7.315 m), from floodmark, from rating curve extended above 3,000 ft'/s (85.0 m'/s) on basis of slope-area measurements of peak flow at gage heights 13.2 ft (4.02 m), 15.0 ft (4.57 m), 19.0 ft (5.79 m), and 24.0 ft (7.315 m), datum then in use; minimum discharge, 20 ftVs (0.566 mVs), Apr. 20, 21, 1984. EXTREMES OUTSIDE PERIOD OF RECORD.—Approximate gage heights of major floods, pointed out by local residents are as followst August 1899, 50 ft (15 m), September 1928, 36 ft (11 m), and September 1932, 34 ft (10 m) at site 1.6 mi (2.6 km) upstream. EXTREMES FOR CURRENT YEAR.—Peak discharges greater than base discharge of 7,000 ft'/s (198 m'/s) and maximum (*) i Discharge Gage height Discharge Gage height Date Time (ft'/s) (m'/s) (ft) (m) Date Time (ft'/s) (m'/s) (ft) (m) Oct. 14 1440 8,940 253 7.39 2.252 Oct. 17 1615 *13,700 388 *9.00 2.743 Oct. 15 1645 8,420 238 7.19 2.192 Oct. 21 1145 8,320 236 7.15 2.179 Oct. 16 1745 7,180 203 6.68 2.036 Minimum discharge, 46 ft'/s (1.30 m'/s), Aug. 11-15. 96 DAY RIO GRANDE £8 MAKATI BASIN 50035000 RIO GRANDE DB MANATI AT CIALB8, PR--Continued DISCHARGE, CUBIC PERT PBR SECOND, HATER YEAR OCTOBER 1990 TO SBPTBMBBR 1991 DAILY MEAN VALUES OCT NOV DEC JAN PEB APR MAY JDN JUIi AUO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-PT CPSM IN. CAT, YR WTR YR 577 306 224 333 308 246 858 625 1030 1180 662 359 618 2180 2350 2420 2630 1510 1910 986 3160 1240 747 617 815 1690 1090 767 642 503 458 33041 1066 3160 224 65540 8.33 9.60 1990 1991 351 296 278 252 493 275 235 226 204 193 186 182 174 161 154 163 178 167 163 604 583 681 541 390 318 301 288 274 213 286 ___ 8810 294 681 154 17470 2.29 2.56 TOTAL 83456 TOTAL 86247 234 210 796 574 305 •190 •170 •160 •155 •153 •153 •153 •220 •200 •200 •249 •175 •165 •160 •155 •151 •150 •150 •170 •160 •145 •140 •145 •140 •180 •350 6658 215 796 140 13210 1.68 1.93 MEAN 229 MEAN 236 •468 •273 •206 •184 •175 •219 •168 •160 •153 149 149 144 139 136 127 121 121 120 117 115 113 113 113 110 107 107 •106 •104 •102 •101 •103 4623 149 468 101 9170 1.17 1.34 MAX MAX •109 •110 •108 •117 132 211 273 136 120 109 150 150 296 177 139 120 168 148 649 361 190 140 124 113 107 •98 •97 •94 ___ ___ ___ 4746 169 649 94 9410 1.32 1.38 3160 MIN 36 3160 MIN 46 •92 •91 •89 •88 •87 87 86 84 83 82 81 81 81 81 79 75 72 72 74 76 72 236 316 131 103 810 816 196 124 106 92 4643 150 816 72 9210 1.17 1.35 AC-PT AC-PT 87 89 125 850 560 147 118 108 108 89 83 84 154 109 •95 •100 •86 •81 •78 •76 •72 •69 •66 •64 •63 •64 •62 •60 •62 •80 —— 3889 130 850 60 7710 1.01 1.13 165500 171100 136 241 253 195 119 81 68 133 100 81 115 220 885 1200 585 216 149 134 128 •200 •450 162 128 114 105 105 105 101 94 88 114 6805 220 1200 68 13500 1.71 1.98 CPSM 1.79 CPSM 1.85 108 87 83 80 79 75 72 72 72 69 68 66 66 65 65 61 57 57 60 63 63 69 62 60 59 54 54 52 53 136 --- 2087 69.6 136 52 4140 .54 .61 IN. 24.25 IN. 25.07 121 68 59 56 54 53 52 204 248 78 62 59 56 54 61 2030 521 165 126 96 81 73 71 67 65 62 59 61 113 70 63 5008 162 2030 52 9930 1.26 1.46 60 56 53 102 100 60 53 49 48 48 47 46 46 46 81 79 99 81 58 53 121 221 293 105 75 67 198 257 94 72 63 2831 91.3 293 46 5620 .71 .82 226 280 110 84 73 66 200 241 99 82 74 126 153 85 77 81 69 76 68 82 91 70 66 66 62 60 70 125 74 70 —— 3106 104 280 60 6160 .81 .90 Estimated 97 RIO GRANDB DB MANATI BASIN 50035500 RIO ORANDB IX MANATI AT HIGHWAY 149 AT CIALBS, RP WATER-QUALITY RECORDS LOCATION.—Lat 18020'46", long 66«28'06", at bridge on Highway 149, about 800 ft (244 m) upstream from confluence with Rio Cialitos, 0.5 mi (0.8 km) north of dale* plasa. DRAINAGE ARBA.--136 mi* (352 km3 ) this exclude, the 6 mi* (15.5 km*) upstream from Lago El Guineo and Lago de Matrullas, flow from which la diverted to Rio Jacaguas. PERIOD OF RECORD.—Water years 1979 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1991 DATE NOV 1990 05... JAN 1991 03... FBB 27... MAY 01... JUN 26... ADO 30... TIME 1100 0835 0950 1030 1205 1205 DIS- CHARGE, INST. CUBIC FEET PER SECOND 585 202 98 116 36 64 SPE- CIFIC CON- DUCT- ANCE (US/CM) 189 223 265 264 373 350 PH (STAND- ARD UNITS) 7.8 7.7 8.1 8.1 8.2 8.0 TEMPER- ATURE MATER (DEG C) 24.0 22.0 24.2 27.0 29.5 28.5 TUR- BID- ITY (NTU) 45 20 20 5.5 5.7 52 OXYGEN, DIS- SOLVED (MG/L) 8.4 7.9 7.7 7.0 6.5 6.8 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 99 90 91 87 85 87 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 18 <10 10 11 16 25 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 23000 K700 K840 560 K50 3100 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 5700 360 K140 720 K10 300 DATE NOV 1990 05... JAN 1991 03... FBB 27... MAY 01... JUN 26... AUG 30... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH NAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CAC03 70 110 87 18 26 22 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L AS CA) AS MG) AS HA) SODIUM AD- SORP- TION (MG/L RATIO 9.9 13 7.9 11 ALKA- POTAS- LINITY CHLO- SIUM, NAT WH SULFATE RIDE, DIS- TOT FBT SULFIDE DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L AS K) 6.1 9.0 0.5 1.7 0.6 1.8 0.5 2.4 CAC03 68 84 100 101 140 75 (MG/L <0.5 5.7 <0.5 12 10 (MG/L AS S) AS SO4) AS CL) 10 15 12 SOLIDS, DATE NOV 1990 05... JAN 1991 03... FBB 27... MAY 01... JUN 26... AUG 30... FLUO- RIDE, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.20 — <0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 23 — — 26 — 25 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 115 -- — 164 -- 141 RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 (TONS SOS- TOTAL TOTAL TOTAL PER PBNDBD (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) 20 19 23 12 6 29 0.780 0.880 0.480 0.19 0.067 0.500 0.020 0.020 0.010 0.010 0.010 0.040 0.800 0.900 0.490 0.200 0.077 0.540 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.030 0.060 0.030 0.040 0.020 0.070 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.27 0.24 0.57 0.46 0.28 0.23 non-ideal count 98 RIO GRANDS DB MANATI BASIN 50035500 RIO ORANDB DB HANATI AT HIGHWAY 149 AT CIALB8, PR—Continued HATER-QUALITY DATA, MATER YBAR OCTOBBR 1990 TO SEPTEMBER 1991 DATE NOV 1990 05... JAN 1991 03... FBB 27... MAY 01... JUN 26... AUG 30... DATE NOV 1990 05... JAN 1991 03... FBB 27... MAY 01... JUN 26... ADO 30... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.30 0.60 0.50 0.30 0.30 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 2300 — — 550 — — NITRO- GEN, TOTAL (MG/L AS N) 1.1 1.2 1.1 0.70 0.38 0.84 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 2 — — 8 — — NITRO- GEN, TOTAL (MG/L AS N03) 4.9 5.3 4.8 3.1 1.7 3.7 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 60 — — 50 — — PHOS- PHORUS TOTAL (MG/L AS P) 0.110 0.070 0.080 0.100 0.070 0.120 MERCURY TOTAL RECOV- ERABLE (UG/L AS HO) <0.10 — — <0.10 — — BARIUM, TOTAL ARSENIC RBCOV- TOTAL BRABLB (UG/L (UG/L AS AS) AS BA) <1 <100 — — <1 200 — — — — — SILVER, SBLB- TOTAL NIUM, RBCOV- TOTAL BRABLB (UG/L (UG/L AS SB) AS AG) <1 <1 — — <1 <1 — — BORON, TOTAL RECOV- ERABLE (UG/L AS B) ^10 — -- ^10 — ~~ ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 — — 20 — — CHRO- CADMIUM MIUM, TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CD) AS CR) <1 4 — — <1 2 — — — — — CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) <0.010 3 — — <0.010 <1 — — COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <10 — — 20 — " MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 0.04 — — 0.02 — — RIO GRANDS DB MANATI BASIN 50035950 RIO CIALITOS AT HIGHWAY 649 AT CIALBS, PR WATER-QUALITY RECORDS LOCATION.—Lat 18°20'18", long 66°28'28-, 100 ft (30 m) upstream from bridge on Highway 649, upstream from mouth, and about 0.4 mi (0.6 km) west of dales plaza. DRAINAGE AREA.—17.0 mi2 (44.0 km2). PERIOD OF RECORD.--Water years 1969-71, 1974 to current year. WATBR-QDALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 99 0.7 mi (1.1 km) DATE NOV 1990 05... DEC 26... FBB 1991 27... MAY 01... JUN 26... ADG 30... TIME 0945 1110 1205 1320 1320 1345 DIS- CHARGE, INST. COBIC PBBT PER SECOND 53 19 17 12 1.2 1.5 SPE- CIFIC CON- DUCT- ANCE (US/CM) 158 232 239 230 242 216 PH (STAND- ARD UNITS) 7.9 8.5 8.2 8.4 7.4 8.0 TEMPER- ATURE WATER (DBG C) 22.5 21.0 23.0 27.0 28.5 28.0 TUR- BID- ITY (NTU) 27 1.8 81 2.5 8.0 6.3 OXYGEN, DIS- SOLVED (MG/L) 8.5 9.5 8.2 8.8 8.1 8.8 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 97 105 95 109 103 110 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 20 <10 28 <10 <10 38 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K7300 530 3400 3800 2000 570 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 9700 480 260 630 370 510 DATE NOV 1990 05... DEC 26... FBB 1991 27... MAY 01... JUN 26... AUG 30... HARD- HARD- NBSS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS CACO3) CACO3 66 92 58 MG/L AS (MG/L 19 25 16 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L AS CA) AS MG) AS NA) SODIUM AD- SORP- TION (MG/L RATIO 7.1 12 ALKA- POTAS- UNITY 8IUM, WAT WH DIS- TOT PET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 4.5 8.2 0.4 1.7 0.5 2.0 4.3 8.9 0.5 1.9 CAC03 64 93 100 79 46 36 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L <0.5 4.9 <0.5 1.4 7.0 (MG/L AS 8) AS S04) AS CL) 11 11 8.5 SOLIDS, RESIDUE DATE NOV 1990 05... DEC 26... FBB 1991 27... MAY 01... JUN 26... AUQ 30... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 — 0.10 SILICA, DIS- SOLVED (MG/L AS 8102) 23 — — 29 — 21 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 111 -- -- 135 -- 100 SOLIDS, DIS- SOLVED (TONS PER DAY) 15.8 — — 4.19 — 0.41 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 36 <1 107 4 10 — NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.990 — 0.670 0.410 0.420 — NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 <0.010 0.010 <0.010 0.010 <0.010 NITRO- GEN, NO2+N03 TOTAL (MG/L AS N) 1.00 0.700 0.680 0.420 0.430 0.730 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.020 0.030 0.020 0.020 0.030 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) — 0.18 0.87 0.18 — 0.17 non-ideal count 100 RIO GRANDS DB MANATI BASIN 50035950 RIO CIALITO8 AT HIGHWAY 649 AT CIALB8, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 05... DEC 26... FEB 1991 27... MAY 01... JDN 26... AUQ 30... DATE NOV 1990 05... DEC 26... FEB 1991 27... MAY 01... JDN 26... AUG 30... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) <0.20 0.20 0.90 0.20 <0.20 0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) — 0.90 1.6 0.62 — 0.93 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) — 4.0 7.0 2.7 — 4.1 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.130 0.050 0.370 0.070 0.080 0.040 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 — — <1 — — SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — 200 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 — — <10 — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 2 — — 1 — — PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 ~ — 10 — — MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1500 90 60 20 0.50 <0.10 <1 <1 <1 <1 <0.010 <0.010 <1 0.01 0.01 101 RIO ORANDB DB MANATI BASIN 50038100 RIO ORANDB DB KANATI AT HIGHWAY 2 NEAR MANATI, PR LOCATION.—Lat li«25'52", long 66«31'37", Hydrologic Unit 21010002, at bridge on Highway 2, and 2.3 mi (3.7 km) west of Manatl. DRAINAQB ARBA.--197 mi* (510 km*)/ approximately, of which about 38 mi* (98 km*) is partly or entirely noncontributing, exclude* 6.0 mi* (15.5 kms ) upstream from Lago Bl Quineo and Lago de Matrullas. WATER-DISCHARGE! RECORDS PERIOD Or RBCORD.—1963-68 (annual »"<""•• discharge only), February 1970 to current year. REVISED RECORDS.--WRD PR-86-li 1970-71 (M) , 1975, 1979, 1982-85 (P). GAOB.—Water-stage recorder. Elevation of gage is 14 ft (4 m), from topographic map. Prior to 1968 crest-stage gage at same site and datum 3.57 ft (1.09 m) lower. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--21 years (1971-91), 384 ftVs (10.87 mVs), 26.47 in/yr (672 mn/yr), 278,200 acre-ft/yr (343 hmVyr)j median of yearly mean discharges, 361 ftVs (10.2 mVs), 261,000 acre-ft/yr (323 hmVyr). EXTREMES FOR PERIOD OF RBCORD.—Maximum discharge, 97,200 fts/s (2,750 ms/s). Oct. 7, 1985, gage height, 33.79 ft (10.299 m) from rating curve extended above 15,000 ftVs (425 mVs) on basis of slope-area measurements of peak flow; minimum discharge, 33 fts/s (0.935 m3 /*). May 12, 1984. EXTREMES OUTSIDE PERIOD OF RBCORD.—Approximate gage heights to gage datum of major floods, pointed out by local residents, are as follows* Sept. 13, 1928, 36.6 ft (11.16 m), Sept. 27, 1932, 36.3 ft (11.06 m), and Aug. 4, 1945, 34.3 ft (10.45 m). EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 9,000 ft3/* (255 m3/*) and maximum (*) i Discharge Gage height Date Time (ftVs) (mVs) (ft) (m) Date Time Oct. 17 2200 <>15,500 439 *28.92 8.815 Oct. 21 1815 Minimum discharge, 85 ftVs (2.41 mVs), July 8. Discharge (ftVs) (mVs) 10,700 303 Gage height (ft) (m) 27.77 8.464 DISCHARGE, CUBIC FBET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 954 970 360 524 521 446 809 1940 1720 3980 1340 702 751 2880 4440 4400 5930 4360 4420 2070 5220 2970 1270 919 1100 2320 2000 1140 e985 693 636 62770 2025 5930 360 124500 10.3 11.85 1990 1991 512 447 413 383 650 401 363 341 309 291 274 e267 e259 246 232 237 252 235 241 310 1170 707 742 447 341 317 331 334 261 302 —— 11615 387 1170 232 23040 1.97 2.19 TOTAL 137860 280 278 1090 1220 609 446 369 320 288 276 272 276 303 285 285 366 270 248 234 226 223 221 221 234 225 208 197 199 196 230 417 10512 339 1220 196 20850 1.72 1.99 MEAN TOTAL 148681 MEAN 623 438 311 258 235 306 265 238 225 221 221 209 200 194 186 180 177 171 167 165 162 158 157 158 156 153 151 149 145 145 146 6670 215 623 145 13230 1.09 1.26 378 MAX 407 MAX 155 157 151 156 206 260 350 240 193 180 247 244 398 313 282 219 266 249 787 1060 418 303 246 210 189 175 157 154 —— 7965 284 1060 151 15800 1.44 1.50 5930 MIN 5930 MIN 146 140 134 132 128 127 129 125 122 118 119 122 117 114 110 103 101 107 119 116 133 232 756 235 149 406 2330 417 253 199 175 7714 249 2330 101 15300 1.26 1.46 62 AC-FT 87 AC-FT 162 153 258 645 2350 347 251 218 231 196 176 180 249 213 180 193 165 155 150 145 137 132 127 120 118 120 116 113 117 112 —— 7829 261 2350 112 15530 1.32 1.48 273400 294900 157 284 292 376 275 181 152 225 203 160 186 158 958 2150 1770 411 264 225 205 191 755 259 196 173 159 156 158 149 143 136 134 11241 363 2150 134 22300 1.84 2.12 CFSM 1.92 CFSM 2.07 179 140 132 127 125 124 121 118 117 113 110 109 109 108 107 105 103 100 103 104 110 114 135 109 101 94 91 88 87 94 —— 3377 113 179 87 6700 .57 .64 IN. 26. IN. 28. 252 133 105 97 94 90 87 94 596 169 118 105 101 95 99 3020 1480 362 247 193 159 142 134 127 124 120 117 114 162 137 119 8992 290 3020 87 17840 1.47 1.70 03 08 106 99 96 94 192 119 103 97 96 93 92 89 90 90 114 116 166 139 120 104 119 e300 e450 e540 e!90 e!40 122 487 189 138 119 5009 162 540 89 9940 .82 .95 110 505 192 143 124 113 187 536 188 140 124 117 264 152 121 129 117 121 114 146 162 123 111 112 107 155 106 210 142 116 4987 166 536 106 9890 .84 .94 Estimated RIO GRANDE DB MANATI BASIN 50038100 RIO GRANDE DB MANATI AT HIGHWAY 2 NEAR MANATI, PR—Continued (National stream-quality accounting network station) WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1969 to current year. WATER-QUALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DIS- OXYOBN, COLI- DATB OCT 1990 03... DEC 03... FEB 1991 05... APR 02... JUN 05... AUG 02... DATB OCT 1990 03... DEC 03... FEB 1991 05... APR 02... JUN 05... AUQ 02... TIME 1015 1100 0945 1300 1030 1020 CALCIUM DIS- SOLVED (MG/L AS CA) 26 31 40 39 41 42 CHARGE, INST. CUBIC FEET PER SECOND 250 817 188 153 125 101 MAGNE- SIUM, DIS- SOLVED (MG/L AS MO) 5.5 6.8 8.2 7.9 8.7 7.9 SPE- CIFIC CON- DUCT- ANCE (US/CM) 210 255 306 301 304 344 SODIUM, DIS- SOLVED (MO/L AS NA) 8.6 11 12 11 13 11 PH (STAND- ARD UNITS) 7.7 8.1 7.8 7.7 7.8 7.8 SODIUM AD- SORP- TION RATIO 0.4 0.5 0.5 0.4 0.5 0.4 TEMPER- ATURE HATER (DBG C) 25.0 24.0 24.0 26.5 27.5 28.5 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 3.2 2.0 1.6 1.8 2.3 2.0 TUR- BID- ITY (NTU) 130 60 9.5 6.5 4.1 5.1 ALKA- LINITY NAT WH TOT FET FIELD MG/L AS CAC03 79 100 120 120 120 130 OXYGEN, DIS- SOLVED (MO/L) 6.5 8.0 8.5 7.1 8.0 6.9 SULFATB DIS- SOLVED (MO/L AS 804) 8.6 8.5 12 9.7 9.0 8.5 DIS- SOLVED (PER- CENT SATUR- ATION) 77 -- 99 86 99 87 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 13 13 13 14 15 15 FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2500 K910 K6500 600 3100 4500 FLUO- RIDB, DIS- SOLVED (MO/L AS F) <0.10 0.20 0.10 0.10 <0.10 0.10 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 6900 K2500 2600 K130 280 420 SILICA, DIS- SOLVED (MQ/L AS SI02) 18 23 16 22 22 21 HARD- NESS TOTAL (MG/L AS CAC03) 88 110 130 130 140 140 SOLIDS, RESIDUE AT 180 DEG. C DIS- SOLVED (MG/L) 145 142 171 164 179 187 DATB OCT 1990 03... DEC 03... FEE 1991 05... APR 02... JUN 05... AUQ 02... SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 136 159 179 179 186 188 SOLIDS, DIS- SOLVED (TONS PER DAY) 97.9 313 86.8 67.7 €0.4 51.0 NITRO- GEN, NO2+NO3 DIS- SOLVED (MG/L AS N) 1.10 0.800 0.700 0.400 0.630 0.520 NITRO- GEN, AMMONIA DIS- SOLVED (MO/L AS N) 0.060 0.070 0.040 0.030 0.030 0.020 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.08 0.09 0.05 0.04 0.04 0.03 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 <0.20 0.20 0.20 0.70 0.50 PHOS- PHORUS TOTAL (MG/L AS P) 0.140 0.170 0.070 0.080 0.150 0.110 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.060 0.060 0.070 0.070 0.090 0.070 PHOS- PHORUS ORTHO, DIS- SOLVED (MG/L AS P) 0.070 0.060 0.070 <0.010 0.070 0.060 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS PO4) 0.21 0.18 0.21 __ 0.21 0.18 K » non-ideal count RIO ORANDB DB MANATI BASIN 103 50038100 RIO QRANDB DB MANATI AT HIGHWAY 2 NEAR MANATI, PR—Continued (National •treaa-quality accounting network atation) HATER-QUALITY DATA, WATER YBAR OCTOBER 1990 TO SBPTBMBBR 1991 DATS OCT 1990 03... DBC 03... FBB 1991 05... APR 02... OUN ALUM- INUM, DIS- 8OLVBD (UG/L AS Ali) ARSENIC DIS- SOLVED (UG/L AS AS) BARIUM, DIS- SOLVED (tra/L AS BA) BERYL- LIUM, DIS- SOLVED (UO/L AS BE) CADMIUM DIS- SOLVED (DQ/L AS CD) CHRO- MIUM, DIS- SOLVED (UQ/L AS CR) COBALT, DIS- SOLVED (DG/L AS CO) COPPER, DIS- SOLVED (UG/L AS CU) IRON, DIS- SOLVED (OCJ/L AS FB) LEAD, DIS- SOLVED (UG/L AS PB) 120 20 <1 <1 43 <0.5 1.0 46 <0.5 <1.0 <1 <3 <3 110 <1 05... AUO 02... DATE OCT 1990 03... DBC 03... FBB 1991 05... APR 02... OUN 05... ADO 02... DATE JUN 1991 05... DATE <10 20 LITHIUM DIS- SOLVED (UG/L AS LI) <4 -- <4 -- <4 <4 TIME 1030 BNDRIN, TOTAL (UG/L) 1 1 MANGA- NESE, DIS- SOLVED (UQ/L AS MN) 16 — 22 -- 26 27 PCB, TOTAL (UG/L) <0.1 BTHION, TOTAL (UG/L) 46 47 MERCURY DIS- SOLVED (UG/L AS HG) <0.1 __ <0.1 -- <0.1 <0.1 ALDRIN, TOTAL (UG/L) <0.010 HBPTA- CHLOR, TOTAL (UQ/L) <0.5 0.6 MOLYB- DENUM, DIS- SOLVED (UQ/L AS MO) <10 __ <10 -- <10 <10 PESTICIDE CHLOR- DANB, TOTAL (UG/L) <0.1 HBPTA- CHLOR EPOXIDB TOTAL (UG/L) <1.0 <1.0 NICKEL, DIS- SOLVED (UG/L AS NI) 3 __ 1 -- <1 <1 ANALYSES DDD, TOTAL (UG/L) <0.010 LINDANB TOTAL (UG/L) <1 2 SELE- NIUM, DIS- SOLVED (UG/L AS SB) <1 __ <1 — <1 <1 DDB, TOTAL (UO/L) <0.010 MALA- THION, TOTAL (UG/L) <3 <3 SILVER, DIS- SOLVED (UG/L AS AG) <1.0 __ <1.0 __ <1.0 <1.0 DOT, TOTAL (UG/L) <0.010 MBTH- OXY- CHLOR, TOTAL (UG/L) 6 2 STRON- TIUM, DIS- SOLVED (UG/L AS SR) 140 __ 180 __ 200 190 DI- AZINON, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) 12 12 VANA- DIUM, DIS- SOLVED (UG/L AS V) 8 -- 6 -- 8 8 DI- ELDRIN TOTAL (UG/L) <0.010 METHYL TRI- THION, TOTAL (UG/L) 5 <1 ZINC, DIS- SOLVED (UG/L AS ZN) 13 _- <3 — 16 5 ENDO- SULFAN, TOTAL (UG/L) <0.010 MI REX, TOTAL (UG/L) JUN 1991 05... <0.010 <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 <0.01 <0.01 DATE JUN 1991 05... PARA- THION, TOTAL (UG/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) PER- THANB TOTAL (UG/L) TOX- APHBNB, TOTAL (UG/L) TOTAL TRI- THION (UG/L) 2,4-D, TOTAL (UG/L) 2,4,5-T TOTAL (UG/L) 2, 4 -DP TOTAL (UG/L) SILVEX, TOTAL (UG/L) <0.01 <0.10 <1 <0.01 <0.01 <0.01 <0.01 <0.01 104 RIO GRANDS DE MANATI BASIN 50038100 RIO QRANDB DB MANATI AT HIGHWAY 2 NEAR MANATI, PR—Continued (National •tream-quality accounting network station) WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1990 03... DEC 1991 03... FEE 05... APR 02... JUN 05... AUQ 02... TIME 1045 1000 0945 1300 1030 1020 STREAM- FLOW, INSTAN- TANEOUS (CFS) 250 817 188 153 125 101 SEDI- MENT, SUS- PENDED (MO/L) 182 137 29 43 705 29 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 123 302 15 18 238 7.9 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM — 95 — 87 48 75 LAGUNA TORTUOUERO BASIN 105 50038200 LACUNA TORTUODBRO ODTLBT NEAR VEGA BAJA, PR HATER-QUALITY RECORDS LOCATION.--Lat 18°28'29-, long 66°26'50-, at bridge on Highway 686, 4.2 mi (6.8 km) northeait of Manatf, and 4.4 Mi (7.1 1m) northwMt of Vega Baja plaza. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water year. 1964-66, 1969-71, 1974 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 18... DEC 04... FBB 1991 07... APR 08... JUN 10... AUG 06... DATE OCT 1990 18... DEC 04... FBB 1991 07... APR 08... JUN 10... AUG 06... DATE OCT 1990 18... DEC 04... FBB 1991 07... APR 08... JUN 10... AUG 06... TIME 1145 0845 1245 0930 0800 0840 ALKA- LINITY NAT WH TOT FBT FIELD MO/L AS CAC03 120 120 120 120 110 100 NITRO- GEN, TOTAL (MO/L AS NO3) 8.0 5.8 5.8 6.9 7.3 6.4 DIS- CHARGE, INST. CUBIC FEET PER SECOND 14 25 14 8.4 5.1 7.8 SULFIDB TOTAL (MG/L AS S) <0.5 — — <0.5 — — — PHOS- PHORUS TOTAL (MG/L AS P) 0.050 0.030 <0.010 0.020 <0.010 <0.010 SPE- CIFIC CON- DUCT- ANCE (US/CM) 1350 1200 1250 1250 1290 1320 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 5 <1 4 1 1 1 BORON, TOTAL RECOV- ERABLE (UG/L AS B) 70 -- -- 110 -- — PH (STAND- ARD UNITS) 7.9 8.3 8.1 8.0 8.0 8.0 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.680 0.490 0.480 0.530 0.540 0.340 COPPER, TOTAL RECOV- ERABLE (UQ/L AS CU) 20 — — 10 — — TEMPER- ATURE WATER (DBG C) 29.5 0.5 27.0 27.0 29.0 29.5 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.010 0.020 0.020 0.010 0.010 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 90 * -- -- 60 -- — OXYGEN, DIS- SOLVED (MG/L) 6.5 6.4 7.7 6.4 5.5 6.1 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.700 0.500 0.500 0.550 0.550 0.350 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 20 — — <10 — — OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 84 76 95 79 70 78 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.370 0.320 0.190 0.180 0.220 0.200 ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -- <10 — — OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 30 28 31 31 32 32 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.73 0.48 0.61 0.82 0.88 0.90 CYANIDE TOTAL (MG/L AS CN) <0.010 — — <0.010 — — COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2000 K25 K16 140 3300 92 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.1 0.80 0.80 1.0 1.1 1.1 PHENOLS TOTAL (UG/L) 1 -- -- <1 -- -- STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K39 K57 K4 100 120 80 NITRO- GEN, TOTAL (MG/L AS N) 1.8 1.3 1.3 1.5 1.6 1.4 MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.09 — — 0.08 — — K » non- ideal count 106 THIS PAGE WAS LEFT BLANK INTENTIONALLY 107 EXPLANATION 038320 SURFACE-WATER STATION AND NUMBER 0397 QUALITY-OF-WATER STATION AND NUMBER 213 WELL AND WELL NUMBER 0123456 Q 1 2 3 4 Figure 16.--Rfo Cibuco basin. 108 RIO CIBUCO BASIN 50038320 RIO CIBUCO BELOW COROZAL, PR LOCATIOH.—Lat 18°21'13", long 66°20'07-, Hydrologic Unit 21010001, on right bank, 150 ft (46 m) downstream from Rio Corosal, and 1.4 mi (2.3 km) northwest of Corosal. DRAINAGE AREA.—15.1 mi* (39.1km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—Hay 1969 to current year. GAGE.—Water-stage recorder. Elevation of gage is 195 ft (59 m), from topographic map. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.—22 years (1970-91), 29.5 ft'/« (0.835 m3/"), 26.53 in/yr (674 mm/yr), 21,370 acre-ft/yr (26.3 hmVyr); median of yearly mean discharges, 32 ftVs (0.91 mVs), 23,200 acre-ft/yr (29 hmVyr). EXTREMES FOR PERIOD OF RECORD.—Maximum discharge, 13,600 ft1/" (385 mVs), Nov. 7, 1979, gage height, 19.80 ft (6.035 m), from rating curve extended above 100 ft3/" (2.83 m3/«) on basis of float and slope-area measurements of peak flowi minimum daily discharge, 1.3 ft3/« (0.037 mVs), July 24-26, 1977. EXTREMES FOR CURRENT YEAR.—Peak discharges greater than base discharge of 2,500 ft'/s (70.8 m3/«) and maximum (*) » Date Oct. 7 Oct. 9 Time 1740 1700 Discharge (ft'/s) (mVs) 4,280 2,760 121 78.2 Gage height (ft) (m) 13.03 3.972 11.15 3.398 Date Oct. 17 Mar. 26 Discharge Time (fts/s) (ms/s) 1700 1730 3,110 »4,700 88.1 133 Gage height (ft) (m) 11.62 3.542 *13.49 4.112 Minimum daily discharge, 4.7 ftVs (0.133 m>/«), Sept. 11. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL SEP 1 106 2 34 3 28 4 57 5 37 6 30 7 310 8 92 9 253 10 97 11 125 12 61 13 55 14 179 IS 192 16 214 17 402 18 535 19 252 20 141 21 e370 22 e!40 23 e80 24 e55 25 64 26 84 27 e50 28 e40 29 e30 30 e30 31 e30 TOTAL 4173 MEAN 135 MAX 535 MIN 28 AC-FT 8280 CFSM 8.91 IN. 10.28 CAL YR 1990 WTR YR 1991 32 29 27 41 32 28 24 23 23 21 20 20 19 19 19 27 21 40 33 44 38 50 33 26 22 43 37 30 66 •6 —— 973 32.4 •6 19 1930 2.15 2.40 TOTAL 12278. TOTAL 11734. 50 73 230 71 46 34 28 25 23 22 23 30 25 21 53 31 22 20 18 18 18 21 19 18 16 15 20 33 44 48 171 1286 41.5 230 15 2550 2.75 3.17 5 MEAN 5 MEAN 109 54 37 30 31 37 30 28 27 28 24 22 20 20 20 20 20 19 19 19 20 19 17 16 16 16 16 16 15 15 20 800 25.8 109 15 1590 1.71 1.97 33.6 MAX 32.1 MAX 19 17 16 148 46 33 32 22 18 21 41 36 39 25 18 33 25 56 152 96 46 34 27 23 22 21 20 21 —— —— —— 1107 39.5 152 16 2200 2.62 2.73 535 MIN 535 MIN 19 17 17 17 17 16 16 16 15 14 16 16 17 16 14 14 13 18 14 12 13 61 24 15 13 290 56 27 20 21 18 872 28.1 290 12 1730 1.86 2.15 17 16 16 16 16 14 17 26 21 16 16 25 58 28 74 31 21 17 16 15 14 14 14 13 13 13 12 11 11 11 —— 602 20.1 74 11 1190 1.33 1.48 6.7 AC-FT 24350 4.7 AC-FT 23280 12 12 19 18 13 11 15 20 15 12 11 56 49 66 31 19 16 17 16 15 14 14 13 12 19 13 13 11 11 12 27 602 19.4 66 11 1190 1.29 1.48 CFSM 2 CFSM 2 18 13 12 11 11 9.9 9.5 9.3 9.0 9.0 9.0 8.6 9.0 9.2 9.2 8.8 8.3 7.2 7.8 8.1 8.6 8.3 12 8.9 7.3 6.6 6.8 7.0 7.9 9.2 —— 279.5 9.32 18 6.6 554 .62 .69 .23 IN. .13 IN. 8.7 7.8 12 10 8.1 7.7 12 14 9.7 8.5 8.1 8.2 7.7 7.2 20 280 32 18 13 12 11 11 10 9.2 8.9 8.5 9.4 9.3 9.8 8.2 8.9 608.9 19.6 280 7.2 1210 1.30 1.50 30.25 28.91 9.2 7.7 7.4 7.3 7.6 7.6 7.2 7.1 6.7 6.1 6.1 6.2 6.5 5.9 6.8 6.6 7.0 5.7 5.1 5.3 5.7 13 10 6.5 8.3 5.8 11 8.9 6.4 5.7 5.4 221.8 7.15 13 5.1 440 .47 .55 6.2 7.9 6.8 6.6 6.6 4.8 5.5 7.0 5.4 5.1 4.7 8.2 8.3 6.0 5.3 7.3 9.6 7.6 6.9 6.9 7.3 7.7 7.7 6.9 6.3 6.0 6.2 7.3 9.2 12 —— 209.3 6.98 12 4.7 415 .46 .52 Estimated 109 RIO CIBUCO BASIN 50038320 RIO CIBUCO BELOW COROZAL, PR--Continued HATER-QUALITY RECORDS PERIOD OF RECORD.--Wat*r ymmrm 1969-76, 1979 to current y«ar. WATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 05... JAN 1991 02... FEB 08... APR 10... JUN 17... AUG 16... DIS- CHARGE, 8PB- INST. CIFIC CUBIC CON- PH TEMPER- TUR- OXYGEN, FEET DUCT- (STAND- ATURB BID- DI8- TIME PER ANCB ARD WATER ITY SOLVED SECOND (US /CM) UNITS) (DBG C) (NTU) (MG/L) 1100 46 282 8.0 25.5 47 8.0 0930 56 255 7.8 21.5 30 8.4 0830 23 314 8.0 20.0 27 8.5 1140 15 1220 8.9 1425 6.4 HARD- HARD- NESS 367 7.9 363 8.0 369 8.2 24.0 3.5 28.5 1.0 30.0 1.0 8 7 7 .1 .8 .9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 92 94 93 94 100 104 OXYGEN COLI- DEMAND, FORM, CHBM- FECAL, ICAL 0.45 (HIGH UM-MF LEVEL) (COLS./ (MQ/L) 100 ML) 21 2000 10 510 19 4000 16 3200 <10 600 11 200 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 4800 1400 2200 840 380 220 ALKA- MAGNB- SODIUM POTA8- NESS NONCARB CALCIUM 8IUM TOTAL WH WAT DIS- DI8- , SODIUM, AD- SIUM, DIS- 8ORP- DI8- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED DATE OCT 1990 05... JAN 1991 02... FBB 08... APR 10... JUN 17... AUG 16... AS MQ/L AS (MG/L (MG/L CACO3) CACO3 110 2 — — 140 8 — 130 5 (MG/L RATIO (MG/L AS CA) AS MQ) AS NA) AS 26 12 — — 37 12 — 34 10 SOLIDS, 15 0.6 — — 19 0.7 — 21 0.8 RESIDUE K) 3 - - 3 - 3 FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- OCT 05 JAN 02 FBB 08 APR 10 JUN 17 AUG 16 RIDE, DIS- SOLVED DATE (MQ/L AS F) 1990 <0.10 1991 . . . 0.10 . . . 0.20 DIS- CONSTI- SOLVBD TUENT8, (MG/L DIS- AS SOLVED 8102) (MG/L) 27 178 — — 27 208 — 35 210 DIS- AT 105 GEN, .1 - - .5 - .7 UNITY WAT WH TOT PET FIELD MG/L AS CACO3 NITRO- GBN, SOLVED DBG. C, NITRATE (TONS SUS- TOTAL PER FENDED (MG/L DAY) (MG/L) AS N) 22.0 15 1.44 33 1.46 26 1.38 8.29 1 2.88 3 2.88 3.63 <1 4.28 NI TRITE TOTAL (MQ/L AS 0 0 0 0 0 0 N) .060 .040 .020 .020 .020 .020 92 270 100 110 110 100 SULFATB 8ULFIDB DIS- TOTAL SOLVED (MG/L (MQ/L AS NITRO- GEN, NO2+NO3 TOTAL (MG/L AS 1 1 1 2 2 4 N) .50 .50 .40 .90 .90 .30 S) AS 8O4) <0.5 20 — — <0.5 19 — 17 CHLO- RIDE, DIS- SOLVED (MG/L AS 20 - - 24 - CL) - - - 29 NITRO- NITRO- GEN, GEN, AMMONIA ORGANIC TOTAL TOTAL (MG/L (MG/L AS N) AS 0.170 0.140 0.030 0.010 0.030 0.010 N) 0.43 0.46 0.57 0.39 0.27 0.69 1 10 RIO CIBOCO BASIN 50038320 RIO CIBDCO BELOW COROZAL, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 05... JAN 1991 02... FBB 08... APR 10... JUN 17... ADO 16... DATE OCT 1990 05... JAN 1991 02... FBB 08... APR 10... JUN 17... AUG 16... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MQ/L AS N) 0.60 0.60 0.60 0.40 0.30 0.70 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 2.1 2.1 2.0 3.3 3.2 5.0 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MQ/L AS N03) 9.3 9.3 8.9 15 14 22 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.340 0.140 0.150 0.540 0.630 0.780 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) 1 — — 1 — — SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 ~ ~ <100 ~ — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 20 -- -- 50 — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 8 — — 1 — -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 20 — — <10 — — MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 2700 260 100 30 0.10 <0.10 20 <0.010 <0.010 0.06 0.08 RIO CIBUCO BASIN 50039500 RIO CIBUCO AT VBQA BAJA, PR LOCATION.—Lat 18°26'53', long 66°22'29", Rydrologic Unit 21010002, on left bank, at bridge on Hwy 2, 0.6 Mi (1.0 km) downstream from Rio Indio, and 0.8 mi (1.3 km) east of Vega B»ja. DRAINAOB AREA.--99.1 mi* (256.7 km*)/ of which 25.4 mi' (65.8 km*), does not contribute directly to surface runoff. WATER-DISCHARGE RECORDS PERIOD OF RECORD.—January 1973 to current year. GAGE.—Water-stage recorder. Datum of gage is 7.79 ft (2.374 m) above mean sea level. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--18 years (1974-91), 131 ftVs (3.710 m3/«), 17.95 in/yr (456 mm/yr), 94,910 acre-ft/yr (117 hmVyr); median of yearly mean discharges* 128 ftj/s (3.62 mVs), 92,700 acre-ft/yr (114 hmVyr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 34,000 ft1/* (963 m'/s), Apr. 12, 1987, gage height, 19.10 ft (5.822 m), from rating curve extended above 3,000 ft3/* (85.0 m'/s) on basis of indirect measurements; minimum discharge, 6.1 ft'/s (0.173 mVs), July 24, 25, 1977. EXTREMES OUTSIDE PERIOD OF RECORD.--Flood of Dec. 11, 1965 reached a stage of 26.2 ft (7.99 m), datum unknown, discharge about 28,000 ft3/* (793 •?/•). EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 3,200 ft'/s (90.6 m'/s) and maximum (*) 1 1 1 Discharge (ftVs) (m»/s) Gage height (ft) (m) Discharge (ft*/*) (»Vs) Gage height (ft) (m) Date Time (ftVs) (m'/s) (ft) (m) Date Time Oct. 17 2100 *12,300 348 *17.29 5.270 No other peak greater than base discharge. Minimum daily discharge, 17 ft'/s (0.481 m'/s), Aug. 14, Sept. 12. DAY DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 184 253 111 235 199 141 224 593 390 960 358 240 191 539 520 688 2200 1770 1650 612 1040 508 359 296 290 428 300 239 212 195 181 16106 520 2200 111 31950 5.24 6.05 1990 1991 169 160 152 142 176 136 127 122 110 92 88 86 82 78 79 93 102 91 310 196 202 218 166 110 122 161 290 220 138 307 —— 4525 151 310 78 8980 1.52 1.70 TOTAL 52750 TOTAL 50389 242 180 946 454 262 197 163 143 130 123 114 138 151 110 146 213 122 104 97 91 91 99 93 103 92 80 80 128 140 255 414 5701 184 946 80 11310 1.86 2.14 MEAN 145 MEAN 138 528 352 222 180 166 220 173 148 143 152 153 128 120 109 102 98 95 88 85 82 80 79 81 79 75 74 72 69 66 64 68 4151 134 528 64 8230 1.35 1.56 MAX MAX 89 70 67 104 427 206 197 195 94 78 120 182 178 118 89 75 132 160 577 738 289 216 170 146 132 123 111 153 — J —— 5236 187 738 67 10390 1.89 1.97 2200 MIN 21 2200 MIN 17 140 103 95 91 88 78 80 77 73 69 71 77 68 67 64 61 62 89 76 64 62 172 192 91 72 156 333 124 87 75, 68 3025 97.6 333 61 6000 .98 1.14 AC-FT AC-FT 66 62 84 143 75 61 58 59 120 58 52 58 215 117 175 224 96 75 66 62 59 56 55 52 51 51 48 47 45 44 2434 81.1 224 44 4830 .82 .91 104600 99950 44 46 142 255 82 65 59 117 175 86 65 67 450 376 348 147 102 96 96 85 85 68 60 55 146 116 71 55 52 47 68 3726 120 450 44 7390 1.21 1.40 CFSM 1.46 CFSM 1.39 148 62 53 46 45 42 42 39 38 36 36 35 34 35 31 31 30 30 33 28 30 31 30 58 37 30 30 32 44 57 —— 1253 41.8 148 28 2490 .42 .47 IN. 19.80 IN. 18.91 62 41 37 e61 e45 e34 e35 e52 e64 e40 e34 32 32 29 40 1030 319 87 49 38 34 34 35 31 32 30 33 36 46 35 37 2544 82.1 1030 29 5050 .83 .95 33 28 31 28 28 30 29 24 19 23 21 23 21 17 21 21 29 26 21 21 27 28 82 31 22 29 30 56 29 22 19 869 28.0 82 17 1720 .28 .33 18 18 24 20 19 18 28 91 26 21 18 17 33 23 19 23 30 40 28 26 45 31 35 28 26 21 21 19 23 30 —— 819 27.3 91 17 1620 .28 .31 e Estimated 1 12 RIO CIBOCO BASIN 50039500 RIO CIBOCO AT VEGA BAJA, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.—Water years 1972 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE TIME DIS- CHARGE INST. CUBIC FEET PER , SPE- CIFIC CON- DUCT- ANCE SECOND (US/CM) OCT 1990 18... DEC 06... FEB 1991 07... APR 08... •TON 14... AUG 06... DATE OCT 1990 18... DEC 06... FEB 1991 07... APR 08... •TON 14... AUG 06... 0915 0800 1440 1155 1030 1115 HARD- NESS TOTAL (MG/L AS CACO3) 130 — — 180 — 190 1000 202 121 54 35 30 HARD- NESS 286 441 348 421 423 437 NONCARB CALCIUM WH WAT DIS- TOT FLD SOLVED MG/L AS (MG/L CACO3 1 — -- 1 -- 7 AS CA) 44 — — 54 — 59 PH (STAND- ARD UNITS) 7.5 8.2 7.8 7.9 7.9 7.9 MAGNE- SIUM, DIS- TEMPER- ATURE WATER (DBG C) 24.0 22.5 23.0 25.5 28.5 28.5 SODIUM, DIS- SOLVED SOLVED (MG/L AS MS) 4.6 — — 10 — 9.6 SOLIDS, FLUO- SILICA, SUM RIDE, DIS- SOLVED DATE (MG/L AS F) OCT 18 DEC 06 FBB 07 APR 08 JUN 14 AUG 06 K - 1990 ... ... 1991 ... ... ... ... non- ideal <0.10 -- -- <0.10 — 0.10 count (MG/L AS NA) 7.5 — — 18 — 17 TUR- BID- ITY (NTO) 22 19 53 4.8 3.1 3.0 SODIUM AD- SORP- TION RATIO 0.3 — -- 0.6 — 0.5 OXYGEN, DIS- SOLVED (MG/L) 6.2 7.5 7.6 7.1 5.3 5.5 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 4.6 — — 3.0 — 2.6 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 72 85 87 85 67 70 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CACO3 120 180 130 160 170 170 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MQ/L) 44 12 23 11 12 <10 SULFIDB TOTAL (MG/L AS S) <0.5 — — <0.5 — — — COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 1000 2500 K15000 600 320 510 SULFATB DIS- SOLVED (MG/L AS SO4) 8.2 -- — 14 — 13 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 59000 470 20000 330 K150 350 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 8.0 — — 22 — 23 RESIDUE OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- CONSTI- DIS- AT SOLVED TUBNTS, SOLVED DBG 105 GEN, GEN, GEN, GEN, GEN, . C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (MG/L DIS- (TONS BUS- TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED SIO2) (MG/L) 11 — — 21 — 19 PER PBNDBD (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS 160 432 - - 238 _ 245 — — 34.6 — 19.6 201 0 17 1 81 1 10 1 5 1 1 1 N) AS .880 0 .15 0 .27 0 .59 0 .36 0 .08 0 N) AS .120 1 .050 1 .030 1 .110 1 .040 1 .020 1 N) AS .00 0 .20 0 .30 0 .70 0 .40 0 .10 <0 N) AS .160 .060 .030 .060 .030 .010 N) 1.0 0.44 0.67 0.54 0.97 — RIO CIB0CO BASIN 50039500 RIO CIBOCO AT VEGA BAJA, PR--Continued HATER-QUALITY DATA, KATBR YBAR OCTOBBR 1990 TO SBPTBMBBR 1991 1 13 DATE OCT 1990 18... DEC 06... FBB 1991 07... APR 08... JUN 14... AUG 06... DATE OCT 1990 18... DEC 06... FBB 1991 07... APR 08... JUN 14... ADO 06... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.2 0.50 0.70 0.60 1.0 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 11000 -- -- 530 .. -- NITRO- GEN, TOTAL (MG/L AS N) 2.2 1.7 2.0 2.3 2.4 1.5 LEAD, TOTAL RECOV- ERABLE (DG/L AS PB) 6 — — 1 — — NITRO- GEN, TOTAL (MG/L AS N03) 9.7 7.5 8.9 10 11 6.6 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 350 -- -. 40 .. — PHOS- PHORUS TOTAL (MG/L AS P) 0.300 0.160 0.190 0.250 0.350 0.280 MERCURY TOTAL RECOV- ERABLE (DG/L AS HG) <0.10 — — <0.10 — — ARSENIC TOTAL (UG/L AS AS) 1 .. -- <1 .. -- SELE- NIUM, TOTAL (DG/L AS SB) <1 -- .. <1 .. — BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 — — <1 — — BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 -- -- 10 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 20 -- -- <10 -- -- CHRO- CADMIUM MIUM, TOTAL TOTAL RBCOV- RECOV- ERABLE ERABLB (UG/L (UG/L AS CD) AS CR) <1 24 __ __ <1 2 — -- ~~ CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UQ/L) tO.010 <1 — — <0.010 <1 — — COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 50 — — 10 — — — MBTHY- LBNB BLUE ACTIVE SUB- STANCE (MG/L) <0.01 — — 0.03 — — 1 14 THIS PAGE WAS LEFT BLANK INTENTIONALLY 1 15 Igneous and >,_ .^ staiw«wiar¥ rocfes v / EXPLANATION A W60 SURFACE-WATER STATION AND NUMBER V0430 QUALITY-OF-WATER STATION AND NUMBER V'oagg QUALITY-OF-WATER PARTIAL RECORD STATION AND NUMBER 0 216 WELL AND WELL NUMBER • 039990 LAKE-ELEVATION STATION 0123456 I——I—J——L—I——J——L_ t I I i I 01234 Figure 17.~Rio de la Plata basin. 1 16 RIO DB LA PLATA BASIN 50039990 LAOO CARITE AT GATE TOMBR LOCATION.—Lat 18°03'46", long 66°05'58", Hydrologic Unit 21010005, on top of a concrete tower at diversion tunnel on Carite Reservoir, 0.7 mi (1.1 km) northwest from Escuela Carite Chino, 1.2 mi (1.9 km) northeast from Central Hidroelectrica de Carite Num. 1 and 1.8 mi (2.9 km) northeast from Escuela Segunda Unidad. DRAINAGE AREA.—8.20 mi 1 (21.24 km1 ). ELEVATION RECORDS PERIOD OF RECORD.—May 1989 to current year. GAGE.—Water stage recorder. Datum of gage !• mean sea level. REMARKS.—Lago Carite Dam was completed in 1913. The operation of the reservoir !• controlled by the utilization of water to meet the demand* for domestic, induetrial and agricultural purpose* in the Guayama Area. The dam !• an earthfill with crest elevation of 1,806 ft (550 m) above mean sea level, with a structural height of 104 ft (32 m) and a lenght of 500 ft (152 m). The dam ha* a capacity of approximately 11,310 acre-feet (13.9 hm3) . The Dam !• operated by the Puerto Rico Electric and Power Authority. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.—Maximum elevation 1,782.02 ft (543.16 m), Feb. 12, 1991; minimum elevation, 1,761.48 ft (536.90 m); June 13, 14 1990. EXTREMES FOR CURRENT YEAR.--Maximum elevation 1,782.02 ft (543.16 m), Feb. 12; minimum elevation, 1,765.94 ft (538.26 m), Oct. 7, 8. Capacity Table (based on Data from Puerto Rico Electric Power Authority) Contents, in acre-feet Elevation, in feet Elevation, in feet 1,746 0 1,760 2.471 1,769 4.561 1,775 1,780 1,784 Contents, in acre-feet 6,194 7,704 8,996 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY OBSERVATION AT 24x00 VALUES OCT NOV DEC JAN FBB MAR APR MAY JUN JUL SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 1766.16 1766.10 1766.04 1766.04 1766.01 1765.97 1765.95 1766.00 1766.39 1766.45 1766.46 1766.60 1766.88 1766.93 1767.04 1767.73 1767.92 1770.05 1770.46 1772.74 1775.52 1775.81 1776.04 1776.63 1777.99 1779.46 1780.45 1780.94 1781.22 1781.59 1781.65 1771.33 1781.65 1765.95 1781.66 1781.63 1781.60 1781.65 1781.63 1781.59 1781.60 1781.62 1781.62 1781.59 1781.56 1781.53 1781.51 1781.49 1781.48 1781.48 1781.47 1781.47 1781.46 1781.48 1781.47 1781.46 1781.45 1781.44 1781.42 1781.44 1781.49 1781.46 1781.46 1781.58 —— 1781.53 1781.66 1781.42 1781.53 1781.50 1781.54 1781.52 1781.46 1781.44 1781.42 1781.41 1781.39 1781.38 1781.36 1781.34 1781.36 1781.50 1781.50 1781.47 1781.44 1781.41 1781.39 1781.38 1781.35 1781.32 1781.31 1781.30 1781.28 1781.24 1781.23 1781.27 1781.31 1781.36 1781.68 1781.40 1781.68 1781.23 1781.64 1781.56 1781.51 1781.49 1781.47 1781.45 1781.48 1781.54 1781.54 1781.54 1781.50 1781.51 1781.50 1781.50 1781.51 1781.49 1781.46 1781.43 1781.40 1781.38 1781.38 1781.36 1781.35 1781.33 1781.30 1781.28 1781.24 1781.26 1781.23 1781.20 1781.22 1781.42 1781.64 1781.20 1781.21 1781.19 1781.20 1781.18 1781.29 1781.71 1781.60 1781.52 1781.48 1781.50 1781.57 1782.01 1781.74 1781.60 1781.54 1781.50 1781.46 1781.50 1781.48 1781.56 1781.57 1781.52 1781.48 1781.48 1781.49 1781.46 1781.44 1781.44 —— —— —— 1781.49 1782.01 1781.18 1781.44 1781.44 1781.48 1781.47 1781.48 1781.48 1781.49 1781.47 1781.45 1781.43 1781.41 1780.95 1780.80 1780.69 1781.00 1781.04 1781.07 1781.05 1780.95 1780.88 1780.80 1780.80 1780.74 1780.66 1780.60 1780.54 1780.45 1780.37 1780.29 1780.20 1780.14 1780.97 1781.49 1780.14 1780.06 1779.98 1779.90 1779.85 1779.73 1779.66 1779.59 1779.56 1779.47 1779.40 1779.39 1779.33 1779.24 1779.17 1779.15 1779.05 1778.96 1778.92 1778.81 1778.76 1778.69 1778.60 1778.52 1778.45 1778.37 1778.28 1778.18 1778.10 1778.00 1777 . 92 —— 1779.04 1780.06 1777.92 1777.96 1777.94 1777.91 1777.89 1777.86 1777.70 1777.62 1777.53 1777 . 45 1777.27 1777.25 1777.14 1777.01 1776.90 1776.78 1776.66 1776.58 1776.50 1776.40 1776.26 1776.18 1776.06 1775.93 1775.80 1776.14 1776.03 1775.89 1775.75 1775.63 1775.53 1775.39 1776.74 1777.96 1775.39 1775.31 1775.16 1775.04 1774.91 1774.81 1774.72 1774 . 63 1774.50 1774.37 1774.25 1774.16 1774.09 1773.95 1773.81 1773.69 1773.57 1773.42 1773.31 1773.16 1773.03 1772.93 1773.06 1773.09 1773.11 1773.08 1773 . 04 1773.10 1773 . 08 1773 . 06 1774 . 13 —— 1773.85 1775.31 1772.93 1774.30 1774.31 1774.31 1774.31 1774.31 1774.27 1774.25 1774.22 1774.20 1774.11 1774.06 1774.00 1773.93 1773.85 1774.07 1774.75 1774.75 1774.72 1774.70 1774.66 1774.62 1774.57 1774.60 1774.65 1774.65 1774.65 1774.53 1774.47 1774.47 1774.46 1774.39 1774.39 1774.75 1773.85 1774.39 1774.37 1774.35 1774.33 1774.30 1774.29 1774.26 1774.23 1774 . 19 1774.16 1774 . 13 1774.09 1774.06 1774.04 1773 . 97 1773.92 1774.01 1773.99 1773.93 1773.92 1773.89 1774.11 1774.10 1774 . 06 1773 . 99 1773 . 93 1773.96 1773 . 94 1773.88 1773.83 1773.78 1774.08 1774.39 1773.78 1773.73 1773 . 67 1773.61 1773.63 1773.64 1773.65 1773.66 1773.66 1773.70 1773.70 1773.70 1773.68 1773.66 1773.64 1773.62 1773.59 1774.32 1774.37 1774.46 1774.47 1774.52 1774.88 1775.11 1775.15 1775.17 1775.22 1775.34 1775.42 1776.11 1776.25 —— 1774.31 1776.25 1773.59 CAL YR 1990 WTR YR 1991 MEAN 1770. MEAN 1777. MAX 1781.68 MIN 1761. MAX 1782.01 MIN 1765. RIO DE LA PLATA BASIN 50043000 RIO DB LA PLATA AT PROYECTO LA PLATA, PR LOCATION.—Lat 18°09'37", long 66°13'44", Hydrologic Unit 21010005, at upstream side of bridge on Highway 173, 0.4 mi (0.6 km) northeast of Proyecto La Plata, and 2.5 mi (4.0 km) upstream from Rio Usab6n. DRAINAGE AREA.--63.0 mi a (163.2 km»), excludes 8.2 mi a (21.1 km1 ) upstream from Carite Reservoir, the flow of which is diverted to Rio Guamani. WATER-DISCHARGE RECORDS 1 17 PERIOD OF RECORD.—1958 (occasional April 1960 to current year. isuremants only), February 1959 to march 1960 (monthly measurements only), GAGE.—Water-stage recorder. Elevation of gage is 850 ft (259 m), from topograpnic map. Prior to Mar. 29, 1961, wire-weight gage read twice daily at same site and datum. REMARKS.—Records poor. The Puerto Rico Aqueduct and Sewer Authority operates a pumping plant about 5 mi (8 km) upstream which can divert as much as 23 ft'/s (0.65 mVs) into Cidra Reservoir. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--31 years (1961-91), 106 fts/s (3.002 mVs), 26.27 in/yr (667 mm/yr), 76,800 acre-ft/yr (94.7 hmVyr); median of yearly mean discharges, 80 ftVs (2.26 mVs), 58,000 acre-ft/yr (72 hmVyr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 59,600 ftVs (1,690 mVs), Aug. 27, 1961, gage height, 22.21 ft (9.818 m), from rating curve extended above 7,000 ftVs (198 m3/s) on basis of slope-area measurement; minimum daily discharge, 2.6 ftVs (0.074 mVs), July 25, 1974. EXTREMES FOR CURRENT YEAR.--Maximum discharge, 5,100 ftVs ( 144 m3/s), Oct. 21, gage-height, unknown; minimum daily discharge, 3.1 fts/s (0.088 mVs), Aug. 14. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY NOV DEC JAN APR MAY JUN JUL AUG SEP 1 e250 2 elOO 3 e45 4 e30 5 e25 6 e20 7 e30 8 e70 9 ellO 10 e80 11 e60 12 e40 13 eSOO 14 e250 15 e450 16 eSOO 17 e350 18 e900 19 elOOO 20 e350 21 e2500 22 e400 23 e200 24 elSO 25 eSOO 26 elSOO 27 e900 28 e400 29 e250 30 elSO 31 e!30 TOTAL 12540 MEAN 405 MAX 2500 MIN 20 AC-FT 24870 CFSM 7.38 IN. 8.51 CAL YR 1990 WTR YR 1991 el 10 elOO e90 e80 elOO e90 e70 e60 e70 e60 e56 e52 eSO e48 e46 e45 e44 e42 e42 e41 e58 e44 e49 e38 e34 e33 e33 e41 e36 e35 1697 56.6 110 33 3370 1.03 1.15 TOTAL 35878 TOTAL 22283 e60 e45 eSO e70 eSO e35 e30 e27 e25 e23 e20 e20 e22 e21 e25 e30 e27 e20 e!6 e!5 e!4 e!3 e!2 e!4 e!3 e!2 ell ell e!2 e60 e300 1103 35.6 300 11 2190 .65 .75 .1 MEAN .2 MEAN elOO e60 e45 e35 e30 e45 e35 e35 e40 e33 e35 e31 e30 e25 e20 e!7 e!5 e!2 elO e!2 e9.0 e7.0 e6.8 e7.0 e6.9 e6.8 e6.4 e8.0 e6.4 e7.2 e8.0 744.5 24.0 100 6.4 1480 .44 .51 elO ell e8.0 e!5 eSO e45 elOO eSO e21 e20 elSO e470 eSOO e70 e60 e35 e30 e27 eSO e45 e60 eSO e30 e25 e22 e27 e21 e20 —— 2022.0 72.2 500 8.0 4010 1.32 1.37 98.3 MAX 3060 61.0 MAX 2500 e22 e!9 e!7 e!6 e!6 e20 e30 e45 e26 e34 e40 e31 e25 e20 e!7 e!5 e!4 e!6 e20 e21 e!5 e20 e40 e25 e!5 e!3 e31 e!8 e!4 e!3 e!2 680' 21.9 45 12 1350 .40 .46 MIN 3.0 MIN 3.1 ell <»100 ell elSO elO e9.6 e9.4 e9.0 elO e!2 e!5 e!6 e!2 e9.6 e!2 ell elO ell elO e9.0 e8.6 e8.4 e8.0 e7.8 e7.6 e7.4 e7.4 e7.2 e7.2 e7.0 e6.8 e25—— 306.0 10.2 25 6.8 607 .19 .21 AC-FT 71160 AC-FT 44200 e30 e20 e!2 elO e9.0 e8.6 e9.4 e8.2 e7.8 e9.0 e!2 e7.4 e7.0 e7.6 e6.6 e7.0 e8.1 elO e7.2 e6.2 e5.8 e7.0 e6.0 e9.0 e7.0 e6.0 e5.6 e5.2 eS.O 509.7 16.4 150 5.0 1010 .30 .35 CFSM CFSM e4.8 e7.0 eS.O e6.8 e6.6 e6.0 e5.2 e5.4 e6.2 e5.8 e5.2 eS.O e6.4 e6.4 e5.8 e5.4 eS.O e4.6 e4.5 eS.O e5.2 e5.2 e6.2 e5.6 e5.4 e5.2 eS.O e4.9 e4.8 e!3—— 175.6 5.85 13 4.5 348 .11 .12 1.79 IN. 1.11 IN. e60 e!5 e9.0 e7.6 e6.0 e5.4 e5.2 e5.8 e7.2 e7.2 e6.0 e5.8 e5.4 e5.3 elO e900 e250 e40 e22 e!6 e!4 e!3 e!2 elO e9.0 eS.O e7.5 elO e!4 ell e9.8 1507.2 48.6 900 5.2 2990 .89 1.02 24.36 15.13 e9.8 e9.6 e8.6 e7.5 e7.0 e6.2 e5.4 eS.O e4.5 e4.0 e3.7 e3.5 e3.3 e3.1 elO e7.6 e6.0 eS.O e4.5 e4.0 e4.5 e9.0 eSO e25 e!5 elO e6.0 e35 e!5 e!2 elO 309.8 9.99 50 3.1 614 .18 .21 e6.0 e5.4 eS.O e4.7 e4.5 eS.O e45 eSO elO e9.0 e7.0 e6.8 e9.0 e8.2 e7.4 e6.4 e90 e80 e25 e!5 e25 e!5 e60 eSO e25 e!4 elO e!3 e!7 e60--- 688.4 22.9 90 4.5 1370 .42 .47 Estimated 1 18 PERIOD Or RECORD.--Hater year* 1958 to WATER-QUALITY RIO DE LA PLATA BASIN 50043000 RIO DE LA PLATA AT PROYBCTO LA PLATA, PR—Continued NATER-QUALITY RECORDS current year. DATA, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 22... DEC 18... FEB 1991 13... APR 12... OUN 18... ADO 14... TIME 1600 0825 1400 1030 1015 1130 DIS- GHARQE, INST. CUBIC FEET PER SECOND 363 18 542 9.3 4.1 2.9 SPE- CIFIC CON- DUCT- ANCE (US/Of) 224 387 180 484 499 546 PH (STAND- ARD UNITS) 7.9 8.2 7.7 8.3 7.9 8.2 TEMPER- ATURE MATER (DBG C) 24.0 22.0 22.0 23.5 27.5 29.5 TUR- BID- ITY (NTU) 40 2.5 85 2.7 2.1 3.2 OXYGEN, DIS- SOLVED (MG/L) 7.3 8.9 8.0 7.8 5.0 5.6 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 88 104 92 92 64 74 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 22 <10 30 16 14 17 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3100 K80 K10000 100 130 K54 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 6700 K190 6800 K150 K61 K22 DATE OCT 1990 22... DEC 18... FEB 1991 13... APR 12... JUN 18... AUG 14... HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB WH NAT TOT FLD MG/L AS CALCIUM DIS- SOLVED (MG/L MAGNE- SIUM, DIS- SOLVED (MG/L SODIUM, DIS- SOLVED (MG/L SODIUM AD- SORP- TION RATIO CACO3) CACO3 AS CA) AS MG) AS NA) 80 5 20 7.2 15 170 0 43 16 33 180 1 43 17 39 ALKA- POTAS- UNITY SIUM, NAT WH DIS- TOT PET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.7 2.0 2.4 3.2 CACO3 70 150 54 180 170 180 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) M W M •* M n «•«••••• O O) •• fH O t H H H H H n t> « t> 1/1 I MM« Ifl H i ri "Silit HHHHH HHMHH H M ft •» I/I 124 RIO DB LA PLATA BASIN 50043800 RIO DB LA PLATA AT COMBRIO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) SEPTEMBER MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MQ/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 13 14 13 15 14 19 44 32 23 15 13 13 21 18 132 303 57 105 60 61 30 18 15 15 19 43 152 50 25 19 14 1385 16440 JULY 11 12 11 11 12 13 29 25 18 13 11 11 17 16 62 134 32 57 40 25 16 17 17 17 19 30 98 70 50 30 14 —— MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN DISCHARGE (CFS) AUGUST 1 .38 .42 .40 .45 .42 .65 3.8 2.2 1.2 .53 .40 .38 1.5 .83 82 167 5.5 19 7.3 4.5 1.3 .80 .66 .70 .95 4.2 44 9.6 3.6 1.5 .55 366.92 4460.58 13 14 15 14 13 15 15 14 13 15 149 54 30 40 35 17 13 14 13 12 12 12 13 . 25 17 14 13 11 431 212 48 1326 6 4 5 5 5 14 20 16 11 13 78 35 24 27 25 17 13 10 5 2 6 10 10 18 15 13 11 10 173 99 40 —— .23 .17 .20 .18 .20 .56 .79 .60 .40 .50 42 5.6 2.0 3.3 2.5 .78 .45 .39 .17 .06 .18 .31 .35 1.3 .69 .49 .38 .31 560 100 5.1 730.19 27 19 22 17 20 64 93 89 47 41 33 35 80 141 85 116 54 38 35 25 22 36 33 126 427 322 100 51 35 48 --- 2281 27 19 22 17 20 64 93 89 47 41 33 35 80 141 85 116 54 38 35 25 22 36 33 126 427 322 100 51 35 48 34 26 15 10 14 40 55 50 31 28 28 26 44 45 48 72 54 47 43 42 42 44 42 73 259 164 127 104 82 69 2.5 1.3 .94 .47 1.1 7.7 16 13 4.1 3.2 2.5 2.5 32 31 13 25 7.9 4.8 3.9 2.8 2.4 4.8 3.9 79 463 161 36 15 7.8 18 966.61 125 RIO DB LA PLATA BASIN 50043800 RIO DB LA PLATA AT COMBRIO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER 484 151 65 65 58 46 41 92 242 156 109 66 1010 434 1060 1990 759 1720 2150 419 6380 806 317 246 1460 3520 1560 570 329 267 260 189 190 107 74 61 32 30 54 115 92 62 46 42 185 386 1300 427 903 1000 199 1090 162 50 56 448 900 539 263 156 122 33 324 80 20 13 9 3 3 15 88 42 19 8 55 273 1420 14900 1230 12000 11700 303 22600 481 43 37 2920 10600 2660 425 144 93 26 .4 .9 .5 .5 MEAN MEAN CONCBN- SEDIMENT MEAN DISCHARGE TRATION DISCHARGE DISCHARGE (CFS) (MG/L) (TONS/DAY) (CFS) NOVEMBER 194 166 145 133 154 140 116 105 127 100 94 87 80 75 71 72 69 66 63 60 101 72 80 62 55 55 57 66 59 58 12 11 77 7 8 9 10 10 10 10 55 11 11 15 12 11 10 8 4 4 66 51 18 13 8 10 10 10 10 10 —— 6.1 4.7 30 2.5 3.3 3.5 3.1 2.8 3.4 2.7 14 2.5 2.4 3.1 2.3 2.1 1.8 1.4 .75 .64 20 9.7 3.7 2.1 1.2 1.4 1.6 1.8 1.6 1.5 100 79 97 152 79 58 51 47 45 42 41 44 43 41 53 60 49 37 32 29 29 30 32 32 36 33 35 34 34 53 655 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) DECEMBER 100 79 97 152 79 58 51 47 45 42 41 44 43 41 53 60 49 37 32 29 29 30 32 32 36 33 35 34 34 53 655 46 49 58 83 52 40 30 20 15 14 12 13 14 15 15 16 17 20 20 17 4 2 2 3 5 6 8 9 8 8 241 13 11 17 35 11 6.2 4.1 2.6 1.8 1.6 1.4 1.5 1.7 1.7 2.3 2.7 2.2 1.9 1.8 1.3 .35 .16 .21 .31 .45 .49 .76 .79 .71 1.2 590 TOTAL 26832 82536.3 2782 137.69 2182 717.23 o c-oo in ^i PI ft o e co <0 e» in H < *i H *i oo ft PI <0 in PI n n 01 a»«0a»pt*i c»ptpiinH in ^>c-cove* ri B o o ^I^IPIPI^I ^i^iin^*^i ^I^I^*^*PI •H 01 Z« «-» « H PS 1 I s~ 2 I o ^ 18 3 ft S ^* in r> m o oov* 9 ™ HSH H H H H n ooo ooo in 01 o o 01 H ^i PI in r> in o«i p S S8 ^ ^riHri pt*iomH HHN PI S Q o^ Z HH HH PI s § sse §4 » iZ in««^iriin r-ooinin n «A in 01 e «A n n H ^i ooonooo r»ne»i i i i !c <-« SE BE O —• >< H H H H «A «A PI e» in n ^iinr>«A<« nnpiwin in n H H n HH i i i i IS 3 B w *"* 2 H Hnm iii i 3 n o f<»- m 8 1 S ~> M r»oinpie» o«piHr>p| p|ininr»«A v* v* r« M c> 0i0inno< noioiii et O 3 PI^IPIPIN o«r>0iinin OHV*COO> «A««ino0i H r« ** in •* in*i*ii i i o 9 § 22^ H M PI«AO«H H H i i i 01 o PI H on a co p PI n *o > O H in a Sjc* n H «« in *irimmo eo PI in et at tj S >• •* •* r« •* •* H o 01 01 e» PI «A n PI n 0i r-in •» •* in inr»eeoe»n ^ 3 033 O> •* •* 00 V* HHHHH H*'*H HriiHH* ••••• ' * * ^ T 5 H oi u 91 m >» 0) PI H H 01 n H O n H n S SSS H lie >• PIOPIPIW e»e»r»«A«A in in in in oo oinoov* t-inininw r»0ioriHin i 8 |S|3 s a—"- 1- - HHHH HHNH i M n n n M PI »» ^ M «» n inr>r>mm oo in o ^> o» 01 in n H e o» n H n o o in O e» in 0) r> «A 0r>e»r> r»«»»»«»«» in in in ^ PI PIPIPIPIPI NPIPIPIPIPI o< 2 Pf —. PI H O 1«£ " S^ a >• HriPi^iin «A r> e» 0) o H n PI ^ in e» 01 o H g S E* 127 RIO DB LA PLATA BASIN 50043800 RIO DB LA PLATA AT CCHBRIO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER TEAR OCTOBER 1990 TO SEPT DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CVS} 24 24 23 21 21 20 20 24 36 33 26 25 32 27 22 24 27 20 19 18 17 17 16 16 15 15 15 14 14 45 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) APRIL 27 17 10 10 16 20 21 29 44 36 23 12 10 10 10 11 13 15 16 15 15 14 10 6 5 5 5 5 5 21 1.7 1.1 .59 .58 .87 1.0 1.1 2.0 4.3 3.2 1.6 .83 .83 .76 .61 .76 .95 .85 .78 .72 .70 .60 .41 .26 .21 .20 .20 .20 .20 10 MEAN DISCHARGE (CPS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MAY 175 271 117 39 27 23 26 31 28 22 20 .22 137 149 49 34 30 27 27 29 26 23 22 22 22 76 37 22 20 18 18 96 127 66 28 22 20 20 20 20 20 20 19 65 118 46 21 13 13 14 21 29 35 36 27 18 50 38 27 23 25 29 95 151 28 3.2 1.6 1.3 1.4 1.8 1.5 1.3 1.1 1.2 72 57 6.9 2.0 1.1 .94 1.0 1.6 2.1 2.2 2.1 1.6 1.0 11 4.1 1.7 1.2 1.2 1.4 MEAN DISCHARGE (CFS) 18 20 21 19 18 16 16 18 19 18 16 16 19 19 16 14 14 13 12 13 13 13 16 15 14 14 14 14 12 21 1991 CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 30 27 20 14 10 7 5 5 5 5 5 5 5 5 5 5 5 5 5 11 15 15 15 15 16 16 16 16 15 20 1.5 1.4 1.1 .72 .46 .30 .23 .25 .27 .24 .22 .22 .26 .27 .21 .18 .18 .17 .18 .36 .52 .53 .62 .65 .61 .60 .59 .57 .51 1.5 TOTAL 670 38.11 1589 460.54 481 15.42 128 RIO DB LA PLATA BASIN 50043800 RIO DB LA PLATA AT COMBRIO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) (CPS) (MQ/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YBAR 176 37 20 16 13 12 12 13 16 16 13 13 12 11 16 2500 349 92 49 36 32 28 26 22 19 18 19 22 31 24 22 3685 47909 JULY 99 49 45 43 39 27 17 17 18 18 17 16 14 12 13 824 157 90 73 70 70 67 65 30 13 7 5 5 5 5 5 —— AUGUST 64 5.2 2.6 1.8 1.3 .85 .56 .57 .74 .78 .60 .53 .45 .36 .67 9640 173 23 10 7.0 6.0 5.2 4.5 1.9 .67 .36 .25 .28 .41 .35 .33 9954.26 98424.18 22 21 19 18 18 17 16 15 15 15 14 14 14 14 32 21 18 17 16 17 22 26 125 55 31 21 24 78 45 24 19 823 6 7 7 7 7 7 7 9 10 11 11 11 11 10 21 11 8 7 7 8 10 13 65 32 13 10 17 42 18 12 10 —— .38 .40 .36 .34 .33 .32 .32 .36 .40 .41 .42 .42 .39 .38 2.1 .65 .42 .35 .31 .38 .60 .91 29 5.4 1.2 .59 1.4 9.6 2.6 .82 .49 62.05 SEPTEMBER 17 17 16 16 16 14 88 113 33 24 21 21 28 24 19 17 210 171 46 28 56 28 130 90 41 24 19 29 38 142 —— 1536 8 8 7 7 7 7 39 176 130 80 58 53 50 49 45 36 99 90 29 20 37 22 71 65 52 38 23 22 28 75 —— —— .39 .37 .33 .30 .29 .27 46 67 13 5.3 3.2 3.2 3.6 3.2 2.3 1.6 178 60 4.0 1.6 6.4 1.8 32 16 5.9 2.7 1.3 1.9 3.0 33—— 497.95 129 RIO DE LA PLATA BASIN 50043800 RIO DB LA PLATA AT COMBRIO, PR—Continued HATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1990 13... 16... 18... 21... JUL 1991 16... 16... 16... DATE OCT 1990 13... 16... 18... 21... JUL 1991 16... 16... 16... TIME 0723 1718 2242 0125 0702 1241 2010 SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM — — — 44 60 40 54 DIS- CHARGE, INST. CUBIC FEET PER SECOND 2190 8370 7620 10700 6764 4060 1520 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM ——— 49 72 59 70 SEDI- MENT, SUS- PENDED (MG/L) 1210 3700 4250 810 2700 7880 4200 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 92 77 91 93 91 91 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 7150 83600 87400 23400 49300 86400 17200 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 100 96 86 95 97 94 96 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM —— — 30 22 16 20 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 100 98 91 97 98 98 99 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM ——— 31 34 21 32 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 100 99 99 99 99 99 100 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM —— — 36 48 28 43 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 96 100 100 100 100 130 RIO DB LA PIATA BASIN 50043800 RIO DB IA PIATA AT CCMBRIO--Continued WATER QUALITY DATA, WATER YBAR OCTOBHR 1990 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OF SUSPENDED SBDIMBNT DATE OCT 1990 02... 13... 13... 18... 18... 20... 21... 21... 25... 25... FEE 1991 12... 13... MAY 01... 14... JUL 16... 16... SEP 18... TIME 1650 0833 1115 1803 1930 1118 0027 0415 0112 0250 2040 0014 1510 1320 1321 1451 STREAM- FLOW, INSTAN- TANEOUS (CFS) 107 2090 1730 2510 4040 385 2410 9850 1840 1620 3260 2927 51 107 4130 754 SBDI- MBNT, SUS- PENDED (MQ/L) 250 730 767 1360 1780 844 5050 12500 450 550 1040 1170 108 184 890 750 SBDI- MBNT, DIS- CHARGE, SUS- PENDED (T/DAY) 72 4120 3580 9220 19400 877 32900 332000 2230 2400 9150 9250 14 53 9920 1530 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 99 99 87 99 78 88 92 77 92 71 94 100 95 83 92 1230 127 308 106 99 RIO DB LA PLATA BASIN 131 50044000 RIO DB LA PLATA NEAR COMBRIO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°14'33", long 66°12'28", at bridge on Highway 156, 0.56 mi (0.9 km) upstream from dam, about 2.0 mi (3.2 km) northeast of Comerio plaia. DRAINAGE ARBA.--139 mi3 (360 km2 ), excludes 8.2 ml2 (21.1 km?) upstream from Carite Reservoir, the flow of which is diverted to Rio Ouamanf. PERIOD OF RECORD.—Water years 1979 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 15... DEC 17... FEB 1991 12... APR 05... JUN 07... AUG 12... TIME 1300 0950 0900 0845 0745 1030 DIS- CHARGE, INST. CUBIC FEET PER SECOND 300 77 177 36 26 23 SPE- CIFIC CON- DUCT- ANCE (US/Of) 245 459 316 433 430 438 PH (STAND- ARD UNITS) 7.9 8.6 8.0 8.2 8.1 8.4 TEMPER- ATURE HATER (DEG C) 26.0 24.0 23.0 23.5 25.5 28.0 TUR- BID- ITY (NTU) 100 1.5 27 2.5 3.7 1.7 OXYGEN, DIS- SOLVED (MG/L) 8.1 8.8 7.8 8.0 7.1 8.3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 100 105 92 93 87 105 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 29 15 25 11 14 12 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K11000 K1500 3400 2800 530 K150 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3900 20 2100 440 200 220 DATE OCT 1990 15... DEC 17... FEB 1991 12... APR 05... JUN 07... AUG 12... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS CAC03) CACO3 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 78 0 19 7.4 17 170 1 40 16 25 160 0 37 17 29 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT FBT SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.8 3.2 0.8 2.4 1 2.9 CACO3 67 160 110 160 150 150 CHLO- SULFATH RIDE, DIS- DIS- SOLVED SOLVED (MG/L <0.5 17 <0.5 19 18 (MG/L AS S) AS SO4) AS CL) 24 29 30 DATE OCT 1990 15... DEC 17... FBB 1991 12... APR 05... JUN 07... AUG 12... FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI02) 23 — — 30 — 28 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 151 -- -- 257 -- 252 RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS BUS- TOTAL TOTAL TOTAL TOTAL TOTAL PER FENDED (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 122 25.1 15.6 21 11 43 5 3 4 1.52 1.66 1.15 0.450 0.340 0.87 0.080 0.040 0.050 0.010 0.010 <0.010 1.60 1.70 1.20 0.460 0.350 0.088 0.100 0.030 0.080 0.360 0.020 0.020 1.0 0.37 0.62 0.0 0.78 0.38 K = non-ideal count 132 RIO DB LA PLATA BASIN 50044000 RIO DB LA PLATA NEAR COMBRIO, PR—Continued WATER-QUALITY DATA, HATER YBAR OCTOBBR 1990 TO SEPTEMBER 1991 DATE OCT 1990 15... DEC 17... FBB 1991 12... APR 05... JUN 07... AUG 12... DATE OCT 1990 15... DEC 17... FEB 1991 12... APR 05... JUN 07... AUG 12... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.1 0.40 0.70 0.30 0.80 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS KB) NITRO- GEN, TOTAL (MG/L AS N) 2.7 2.1 1.9 0.76 1.2 0.49 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 12 9.3 8.4 3.4 5.1 2.2 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.270 0.460 0.270 0.270 0.290 0.290 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) .1 — — 1 — — SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 ~ — <100 — ~ SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 30 — — 40 — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — ~ CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 8 -- — <1 — -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 30 — — 10 — ~ MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 6300 210 160 20 <0.10 <0.10 20 <0.010 «0.010 0.03 0.03 RIO DE LA PLATA BASIN 133 50044830 RIO GUADIANA AT GUADIANA, PR LOCATION. — Lat 18*18' 08", long 66°13'24", Hydroloaic Unit 21010005, at left bank downstream side of river, 1.3 ml (2.1 km) Bast of Plaxa de Naranjlto, 0.9 ml (1.4 km) west from Intersection of roads 167 and 164 at km 8.9 and 2.9 ml (4.7 km) norwest from Represa Comcrio. DRAINAGE AREA. --9. 19 ml* (23.80 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD. —JUly 1990 to current year. GAGE. — Water-stage recorder and crest-stage gage. Elevation of gage Is 230 ft (70 m) , from topographic map. REMARKS. — Records fair except those for estimated dally discharges, which are poor. Gage-height and precipitation satellite telemetry at station. EXTREMES FOR PERIOD OF RECORD . - -Maximum discharge, 4,600 ft'/s (130 •?/•), Feb. 5, 1991, gage height, 11.54 ft (3.517 m), from rating curve extended above 500 ftVs (14.2 mVs) on basis of step-backwater analysis; minimum daily discharge, 2.6 ftVs (0.074 •?/•), June 27, 28, 1991. EXTREMES FOR PERIOD JULY TO SEPTEMBER 1990 AND WATER YEAR 1991. —Peak discharges greater than base discharge of 1,800 ftVs (51.0 mVs) and maximum (*) t Date Time Discharge (ftVs) (mVs) Gage height (ft) (m) Date Time Sept. 3, 1990 1745 Oct. 9, 1990 1640 Oct. 15 1550 Oct. 16 1400 *471 1,800 2,340 1,870 13.3 51.0 66.3 53.0 *6.41 8.55 9.20 8.63 1.954 2.606 2.804 2.630 Oct. 18 1940 Oct. 19 1735 Feb. 5,1991 1630 Discharge (fjt/s) (mVs) 2,120 1,800 *4,600 60.0 51.0 130 Gage height (ft) (m) 8.92 8.55 *11.54 2.719 2.606 3.517 Minimum daily discharge, 4.0 ftVs (0.113 mVs), Aug. 21, 1990; 2.6 ftVs (0.074 •?/•), June 27, 28, 1991. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAILY MEAN VALUES DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP •4.1 •5.8 •5.4 •4.3 •5.0 •6.8 •8.8 e6.2 •6.0 •8.2 •6.4 •7.0 elO •9.0 •6.0 5.1 4.6 4.6 4.2 4.2 4.0 5.8 4.9 4.3 6.2 4.5 4.1 24 14 5.5 4.8 203.8 6.57 24 4.0 404 .72 .82 6.6 5.7 66 22 38 15 59 28 13 9.8 13 8.4 7.3 30 14 8.6 7.2 13 8.4 7.0 6.5 6.7 14 7.9 23 11 9.2 8.2 8.5 8.5 —— 483.5 16.1 66 5.7 959 1.75 1.96 Estimated 134 RZO DS LA PLATA BASIN 50044830 RZO OUADIANA AT OUADZANA, PR--Continued DISCHARGE, CUBIC PBBT PBR SECOND, MATER YEAR OCTOBER 1990 TO SBPTBHBBR 1991 DAILY MEAN VALUES DAY OCT MOV DBC JAN FBB MAR APR MAY •TON JUL ADO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MZN AC-FT CFSM IN. 7.9 5.7 15 56 33 19 108 46 194 186 68 30 20 146 234 225 208 306 281 102 322 81 44 38 73 87 40 27 22 19 17 3060.6 98.7 322 5.7 6070 10.7 12.39 16 15 15 16 15 14 13 13 13 12 12 12 11 11 10 13 11 11 11 12 12 26 14 11 10 11 14 11 33 25 —— 423 14.1 33 10 839 1.53 1.71 25 37 105 39 21 16 14 13 12 12 12 14 11 11 11 10 9.5 9.4 9.3 9.3 9.3 11 13 13 9.9 9.2 9.2 10 18 42 66 611.1 19.7 105 9.2 1210 2.15 2.47 58 29 19 15 21 25 21 18 19 20 18 16 14 13 12 12 11 11 11 10 9.7 9.2 9.5 8.9 8.9 8. 8. 7. 7. 7. 10 470.4 15.2 58 7.9 933 1.65 1.90 9.6 8.5 8.3 23 335 58 23 16 14 15 14 17 18 14 12 13 12 45 59 44 30 20 16 14 12 11 11 14 —— 886.4 31.7 335 8.3 1760 3.44 3.59 11 11 10 12 10 11 11 10 9.5 9.1 10 8.8 9.2 8.9 8.1 7.3 7.2 10 7.6 7.0 8.1 101 24 12 9.7 11 12 9.3 8.3 7.9 7.6 399.6 12.9 101 T.O 793 1.40 1.62 7.6 8.7 7.5 7.1 7.1 7.0 9.1 21 11 8.9 10 16 24 19 56 18 12 11 9.6 8.6 .0 .7 .4 .9 .7 .5 .4 6.3 5.8 5.8 —— 346.7 11.6 56 5.8 688 1.26 1.40 5.8 7.2 7.1 6.0 5.9 5.9 7.6 19 9.5 7.1 7.6 11 11 9.7 7.1 6.1 5.7 6.8 9.5 7.6 5.8 5.1 4.8 4.8 18 5.9 4.9 4.5 4.3 5.7 5.2 232.2 7.49 19 4.3 461 .82 .94 5.1 3.9 3.6 3.6 3.5 3.8 3.7 3.3 3.1 3.0 3.0 3.0 2.8 2.8 2.8 2.7 2.7 3.0 3.3 3.2 3.1 3.1 29 4.4 3.3 2.8 2.6 2.6 7.5 32 —— 156.3 5.21 32 2.6 310 .57 .63 6.4 3.7 4.6 4.0 3.3 3.0 7.4 4.4 3.2 2.9 3.0 2.9 2.9 2.7 27 250 22 9.0 6.5 5.3 .7 .4 .1 .3 .9 .0 .2 .5 .0 .2 17 433.5 14.0 250 2.7 860 1.52 1.75 7.1 5.1 4.4 4.1 4.0 3.8 3.8 4.1 3.7 3.5 3.5 3.6 3.7 «3.6 «3.4 «3.9 4.6 4.0 3.2 3.7 3.5 41 9.6 5.1 4.4 4.1 11 6.7 4.6 4.0 3.9 178.7 5.76 41 3.2 354 .63 .72 3.5 3.6 3.2 3.0 3.1 3.1 3.5 3.1 3.0 3.0 2.8 6.9 3.7 2.9 2.7 3.3 6.8 4.0 3.3 3.3 3.3 4.8 5.2 3.9 3.4 3.3 3.3 3.2 4.3 12—— 118.5 3.95 12 2.7 235 .43 .48 WTR YR 1991 TOTAL 7317.0 MEAN 20.0 MAX 335 MZN 2.6 AC-FT 14510 CFSM 2.18 IN. 29.62 e BctiMted 135 RIO DB LA PLATA BASIN 50044850 RIO OOADIAHA NEAR NARANJITO, PR HATER-QUALITY RECORDS LOCATION.--Lat 18°18'39-, long 66»13'28-, at »t««l-ero««-brida« 0.8 mi (1.3 km) north%M«t of (1.9 km) up«tr«am fro* mouth and about 2.0 mi (3.2 km) north«a«t of Naranjito plaza. DRAINAGE ARBA.--4.0 mi* (10.3 km3). PERIOD OF RECORD.--Water y»ar 1979 to currant y«ar. HATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 Highway 1C4, 1.2 mi DATE OCT 1990 17... DEC 17... FEB 1991 12... APR 05... JUN 07... AOQ 12... TIKE 0945 0820 1110 1130 1000 1245 DIS- CHAROB, INST. CUBIC FEET PER SECOND 72 11 12 7.9 8.0 4.4 SPE- CIFIC CON- DUCT- ANCE (US/CM) 237 32C 297 338 335 377 PH (STAND- ARD UNITS) 8.0 8.1 8.1 i 8.3 8.1 8.2 TEMPER- ATURE HATER (DBG C) 23.5 21.5 23.0 24.5 2C.O 29.0 TUR- BID- ITY (NTU) 32 1.2 3.3 12 1.0 1.4 OXYGEN, DIS- SOLVED (MG/L) 8.6 8.1 8.0 9.2 7.3 7.1 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 100 101 91 108 88 90 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 15 10 11 <10 10 12 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 27000 R6000 K730 340 3000 470 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 2700 2600 500 K170 K1200 350 DATE OCT 1990 17... DEC 17... FEB 1991 12... APR 05... JUN 07... AUG 12... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH NAT DIS- (MG/L TOT FLD SOLVED AS 87 130 150 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) 19 9.6 13 30 14 16 35 16 19 SODIUM AD- SORP- TION (MG/L RATIO ALKA- POTAS- LINITY CHLO- SIUM, NAT WH SULFATB RIDE, DIS- TOT FBT SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L 0.6 2.5 0.6 2.2 0.7 2.6 73 110 110 110 120 130 <0.5 11 <0.5 15 13 (MG/L AS K) CAC03 AS S) AS SO4) AS CL) 14 22 25 SOLIDS, RESIDUE DATE OCT 1990 17... DEC 17... FEB 1991 12... APR 05... JUN 07... AUG 12... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 24 -- — 25 -- 26 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 137 -- -- 190 -- 215 SOLIDS, DIS- SOLVED (TONS PER DAY) 26.6 -- — 4.06 -- 2.55 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 33 2 9 67 7 8 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.58 1.28 1.69 -- 1.18 1.09 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.020 0.010 <0.010 0.020 0.010 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.60 1.30 1.70 1.20 1.20 1.10 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.040 0.030 0.010 <0.010 0.030 0.030 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.16 -- 0.29 -- 0.47 0.27 non-id«al count 136 RIO DB LA PLATA BASIN 50044850 RIO GUADIANA NEAR NARANJITO, PR—Continued WATER-QUALITY DATA, WATER YBAR OCTOBER 1990 TO SBPTBMBBR 1991 DATE OCT 1990 17... DBC 17... FEB 1991 12... APR 05... JUN 07... AUQ 12... DATE OCT 1990 17... DBC 17... FBB 1991 12... APR 05... JUN 07... AUQ 12... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MQ/L AS N) 0.20 <0.20 0.30 0.30 0.50 0.30 IRON, TOTAL RECOV- ERABLE (UQ/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.8 ~ 2.0 1.5 1.7 1.4 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 8.0 — 8.9 6.6 7.5 6.2 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.150 0.140 0.160 0.210 0.250 0.320 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 — — <1 — -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — ~ <100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RBCOV- BRABLB (UG/L AS B) <10 — — 30 — -- ZINC, TOTAL RECOV- ERABLE (UQ/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 8 -- — <1 — -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 30 — — <10 — — MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MQ/L) 2500 210 80 20 «0.10 «0.10 <0.010 <0.010 0.03 0.03 RIO DB LA PLATA BASIN 50045000 IiAOO LA PLATA AT DAMSITE, PR 137 LOCATION. — Lat 18°20'40", long 66°14'10-, Hydrologic Unit 21010005, 2.9 mi (4.7 km) at northeast of Plan de Naranjito, 2.7 mi (4.3 km) West of Road 167, km 15.3, Buena Vista, Bayamon, 5.2 mi (8.4 km) east of Plaza de Coroial. DRAINAGE AREA.--181 mi* (469 lot*). ELEVATION RECORDS PERIOD OF RECORD.—February 1989 to current year. GAGE.—Water-stage recorder. Datum of gage is Man sea level. REMARKS.--Lago La Plata first construction phase was completed in 1974 and the second construction phase to provide the spillway with bascule gates was completed in October 1989. The •mirlimiii storage is 37,000 ac-ft (45.6 hm3 ) and its purpose is the supply of water for domestic and industrial use. La Plata Dam is a concrete gravity structure located across the Rio de la Plata, the dam has an overall length of 774 ft (236 m) and a marl mm height of about 131 ft (40 m). The dam spillway is provided with 6 bascule gates. The spillway crest has a total clear length of 690 ft (210 m), an elevation of 155 ft (47 m). The Dam is owned and operated by Puerto Rico Aqueduct and Sewer Authority. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.—Maximum elevation, 159.41 ft (48.59 m), May 8, 1990; minimum elevation, 146.96 ft (44.79 m), Aug. 4, 1989. EXTREMES FOR CURRENT YEAR.--Maximum elevation, 158.15 ft (48.59 m), Oct.21; minimum elevation, 146.70 ft (45.16 m), July 15. Capacity Table (based on data from Puerto Rico Aqueduct and Sewer Authority) Elevation, in feet 98.43 131.24 154.60 Contents, in acre-feet 2,760 11,360 22,720 Elevation, in feet 164.05 170.61 175.52 Contents, in acre-feet 28,550 33,160 37,040 DAY ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY OBSERVATION AT 24iOO VALUES OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG 26 27 28 29 30 31 MEAN 155.35 MAX 157.21 MIN 154.90 154.98 155.11 154.89 154.80 155.48 154.58 154.84 154.96 155.05 155.59 154.45 154.41 154.79 155.08 154.58 154.12 155.00 152.93 154.20 154.83 153.08 150.82 153.44 148.34 151.25 155.52 146.83 151.37 153.66 150.03 SEP 1 2 3 4 5 6 7 8 9 10 155.12 155.01 154.98 155.03 154.99 154.90 155.27 155.06 155.31 155.28 155.09 155.11 155.07 155.06 155.11 155.08 155.02 154 . 99 155.01 154.97 154.97 155.00 155.12 154.96 154.88 154.81 154.78 154.75 154.74 154.73 155.05 154.99 154.95 154.92 154.98 155.04 154.94 154.97 155.02 155.01 154.47 154.44 154.41 154.48 155.59 155.14 155.14 155.03 154.91 154.89 154.84 154.95 154.86 154.81 154.78 154.79 154.79 154.83 154 . 80 154.78 154.48 154.45 154.36 154.27 154.17 154 . 07 153.98 154 . 10 154.08 154 . 04 153 . 08 153.79 154 . 24 154.25 154.18 154.09 154.04 154.59 154.61 154.52 153.44 153.28 153.12 152.95 152.78 152.60 152.41 152.23 152.05 151.86 148.98 148.99 148.96 148.82 148.61 148.37 148.34 148.16 147.98 147.78 153.66 153.52 153.36 153 . 19 153 . 03 152.86 152.70 152.50 152.29 152.07 149.88 149.70 149.51 149.25 149.02 148.82 148.60 148.85 148.72 148.52 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 155.06 154.96 155.23 155.20 155.58 155.95 155.29 157.21 155.37 155.44 155.82 155.17 155.18 155.19 156.32 154.95 154.94 154 . 91 154.90 154 . 89 154.92 154.91 154.99 154.93 154.92 154.99 155.00 154.95 155.01 154.90 154.71 154.74 154.75 154.73 154.77 154.79 154.80 154.77 154.72 154 . 67 154 . 63 154.61 154 . 63 154.66 154 . 63 154.98 154.95 154.94 154.92 154.92 154.90 154.89 154.85 154.83 154.79 154.76 154.74 154.74 154.74 154.76 155.20 155.59 155.13 155.04 154.94 154.94 155.00 155.18 155.16 155.11 155.09 155.00 154.92 154 . 86 154 . 84 154.79 154.79 154.80 154.78 154.76 154.73 154.67 154.70 154.73 154.71 154.69 155.08 155.02 154.85 154.72 154.01 154.25 154.40 154.46 155.00 154.82 154.74 154 . 65 154.52 154.40 154.29 154 . 14 154.01 153.87 153.72 154.41 154.37 154.35 154.83 154.78 154.66 154 . 54 154.49 154.43 154.39 154.27 154.13 153.97 153.82 154.10 151.66 151.44 151.23 151.06 150.89 150.63 150.41 150.30 150.10 149.87 149.63 149.40 149.54 149.39 149.19 147.56 147.31 147.07 146.83 146.91 155.52 154.92 154.78 154.71 154.65 154 . 55 154.45 154.30 154.16 154.02 151.87 151.68 151.44 151.21 151.05 150.94 150.77 150.58 150.32 150.14 150.03 150.17 150.46 150.53 150.45 148.30 148.17 148.01 147.82 147.62 147.39 147 . 51 148.18 148.18 148.09 148.03 147.98 148.12 148.34 148.36 156.22 155.25 155.10 155.05 155.14 155.10 154.91 154.92 154.91 155.03 154 . 97 154 . 62 154.58 154.74 154.99 154.93 155.48 154.70 154.64 154.57 154.51 154.45 154.46 154.82 154.82 154.88 154.78 154.88 154.79 154.71 154.66 154.58 153.56 153.41 153.24 153.09 152.93 154.15 154.12 154.01 153 . 85 153.69 153 . 58 148.96 148.74 148.50 148.34 148.62 153.86 153.72 153.67 153.55 153.48 153.71 150.29 150.34 150.43 150.42 150.26 150.06 148.40 148.44 148.34 148.33 148.53 148.43 149.88 147.39 WTR YR 1991 MEAN 153.33 MAX 157.21 MIN 146.83 138 RIO DB LA PLATA BASIN 50045010 RIO DE LA PLATA BELOW LA PLATA DAM, PR LOCATION. —Lat 18°20'45 11 , long 66°14'1V, Hydrologic Unit 21010005, 2.8 ml (4.5 km) weat of Road 167, km 15.3, Buena Vista, Bayamon, 5.0 ml (8.0 km) eaat of Plaza de Corozal, 3.0 ml (4.8 km) northeast of Plata de Naranjito. DRAZNAGE AREA.--173 ml* (448 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—July 1989 to current year. GAGE.—Water-stage recorder. Elevation of gage 164 ft (30 m), from topographic map. REMARKS.—Record* poor. Regulation at all atagea by Puerto Rico Aqueduct and Sewer Authority reservoir upstream from gage. Gage-height satellite telemetry at station. EXTREMES FOR PERIOD OF RECORD.—Maximum discharge, 48,800 ft'/s (1,380 mVa), Sept. 18, 1989, gage height 22.98 ft (7.00 m), from rating curve extended above 10,000 ftVa (283 mVa), on basis of step-backwater analysis; minimum discharge, no flow many daya. EXTREMES FOR CURRENT YEAR.—Maxtmun discharge, 16,200 ftV* (459 mVa), Oct. 21, gage-height 16.30 ft (4.97 m), from rating curve extended above 10,000 ft'/a (283 m]/a) on basis of step-backwater analysis; minimum discharge, no flow many daya. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 110 140 88 107 95 65 629 218 579 1060 410 145 417 521 1180 2720 1500 2050 3470 484 8790 1010 391 308 845 3810 1670 572 374 254 302 34314 1107 8790 65 68060 6.41 7.39 1990 1991 218 182 178 154 155 171 149 124 125 120 101 92 82 69 62 63 70 67 90 65 78 110 102 102 84 51 55 54 55 185 —— 3213 107 218 51 6370 .62 .69 TOTAL 46569 TOTAL 52462 166 152 377 298 152 86 53 37 28 22 18 16 19 16 16 31 35 26 13 5.6 2.1 1.5 1.3 1.5 1.7 1.4 1.2 5.3 52 182 813 2629.6 ; 84.8 813 1.2 5220 .49 .57 .02 MEAN .90 MEAN 686 224 123 81 56 108 121 69 71 101 88 72 55 48 41 39 32 26 21 15 10 6.7 5.3 6.3 7.1 6.3 2.5 1.9 1.9 1.7 2.1 1128.8 68.7 686 1.7 4220 .40 .46 128 MAX 144 MAX 2.2 2.1 2.0 3.3 1020 452 337 202 117 77 180 291 1070 329 207 109 96 165 350 289 246 192 135 91 68 60 62 72 —— 6226.6 222 1070 2.0 12350 1.29 1.34 8790 8790 75 91 92 54 37 34 38 44 47 35 33 34 31 29 24 15 7.3 4.1 1.6 1.2 .50 217 267 123 38 9.4 86 74 28 8.7 2.8 1581.60 51.0 267 .50 3140 .30 .34 MIN .00 MIN .00 2.0 1.9 2.7 2.9 3.0 2.9 2.9 3.8 4.2 3.2 3.4 3.5 4.5 3.6 68 107 38 11 3.9 3.3 3.3 3.1 2.3 1.9 1.8 1.7 1.5 1.4 1.3 1.2 —— 295.2 9.84 107 1.2 586 .06 .06 AC-FT 92370 AC-FT 104100 1.1 1.1 1.2 1.6 1.2 1.1 1.0 2.5 1.5 .68 .49 .48 .62 14 22 5.7 .77 .33 .29 .26 .25 .17 .14 .12 1.4 .62 .42 .29 .23 .19 .26 62.01 2.00 22 .12 123 .01 .01 CFSM CFSM .46 .41 .29 .23 .17 .15 .15 .12 .10 .07 .04 .04 .03 .02 .01 .01 .00 .45 .47 .28 .17 .10 .19 .17 .12 .08 .03 .02 .02 .41 —— 4.81 .16 .47 .00 9.5 .00 .00 .74 IN. . 83 IN. .45 .27 .20 .21 .16 .09 .25 .44 .31 .20 .13 .07 .05 .02 .05 1330 507 121 36 7.0 1.0 .38 .18 .11 .08 .04 .03 .10 .15 .07 .39 2006.43 64.7 1330 .02 3980 .37 .43 10.03 11.29 .39 .17 .08 .03 .01 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 4 e.02 e.03 e.02 e.03 e.02 0.81 ( .026 .39 .00 1.6 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .02 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 i.OO .00 .00 .01 .01 — ).04 001 .02 .00 .08 .00 .00 Estimated 139 RIO DB LA PLATA BASIN 50046000 RIO DB LA PLATA AT HIGHWAY 2 NEAR TOA ALTA, PR LOCATION. --Lat 18«24'41", long 66«15'39", Hydrologic Unit 21010005, on left buk, at downstream aid* of bridge on Highway 2, 1.3 mi ( 2.1 km) downstream from Rio Lajaa, and 1.6 mi (2.6 km) northwest of Toa Alta, 8.0 mi (12.9 km) downstream from Puerto Rico Aqueduct and Sawar Authority raaarvoir. DRAINAGE ARBA.--208 mi* (539 km*), excludea 8.2 mi* (21.2 km*) upatraam from Lago Carita, flow from which la divartad to Rio Guamani. Araa at aita uaad prior to Saptambar 25, 1984, 200 mi* (518 km*). WATER-DISCHARGE RBCORD8 PERIOD OF RECORD.--November 1959 (meaauramant only), January 1960 to currant yaar. Prior to Octobar 1984, published aa Rio da la Plata at Toa Alta, PR; Octobar 1984 to Saptambar 1988 published aa 50046900. GAGE.—Mater-stage raeordar. Datum of gaga la 9.15 ft (2.789 m), abova maan aaa laval. Prior to Octobar, 1984, at •ita about 1.0 mi (1.6 km) upatraam at maan aaa laval datum. REMARKS.—Racorda fair except thoaa for aatimatad daily discharges, which ara poor. Regulation at all stages by Puerto Rico Aqueduct and Sawar Authority reservoir upatraam from gaga. Gage-height and precipitation satellite telemetry at station. AVERAQB DISCHARGE.--31 years (1961-91), 272 fts/s (7.703 m'/s), 18.47 in/yr (469 mm/yr), 197,100 acre-ft/yr (243 hmVyr); median of yearly maan discharges, 234 fts/s (6.63 mVa), 170,000 acre-ft/yr (210 hm>/yr). EXTREMES FOR PERIOD OF RBCORD.—Maximum discharge, 95,500 ft'/s (2,700 mj/s), Sept. 6, 1960, gaga height, 36.35 ft (11.079m), from floodmark, from rating curve extended above 12,000 ft'/a (340 mj/s) on basis of contracted-opening meaauramant of peak flow at aita 1.0 mi upstream and different datum/ minimum discharge, 2.2 ftVs (0.062 mVs), Apr. 25, 1984. EXTREMES OUTSIDE PERIOD OF RBCORD.—Approximate discharges and elevations of major floods, aa pointed out by local residents ara aa followst Sept. 13, 1928, 120,000 ft'/s (3,400 mVs), gaga height, 37.4 ft (11.40 m); June 16, 1943, 82,000 ftVs (2,322 mj/s), gaga height, 34.4 ft (10.48 m), at aita 1.0 mi upatraam and different datum. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 6,000 ft'/a (170 mVs) and maximum (*) t Discharge Gaga height Discharge Gage height Data Time (ft'/a) (mVs) (ft) (m) Data Time (f't/a) (mVa) (ft) (m) Oct. 16 2215 8,400 238 13.04 3.974 Oct. 21 1515 *18,300 518 *17.64 5.377 Oct. 19 0245 12,100 343 15.07 4.593 Oct. 26 0700 6,280 178 11.60 3.536 Minimum discharge, 12 ft'/s (0.340 mVs), Sept. 11, 12. 140 RIO DB LA PLATA BASIN 50046000 RIO DB LA PLATA AT HIGHWAY 2 NEAR TOA ALTA, PR—Continued DISCHARGE, CUBIC FBBT PBR SECOND, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT MOV DBG JAN PEB MAR APR NAY JUN JUL ADO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX NIN AC-PT CPSN IN. CAL YR WTR YR e450 eSOO e2SO e450 e400 e3SO e700 e2000 elSOO e3000 eSOO eSOO 449 760 1550 3810 3090 2640 6380 1200 9890 2210 777 535 1030 3540 2370 918 588 384 396 53417 1723 9890 250 106000 8.62 9.95 1990 1991 291 232 207 187 175 188 177 145 131 134 113 104 93 83 79 74 79 79 122 111 104 112 110 93 114 111 127 87 68 226 —— 3956 132 291 68 7850 .66 .74 TOTAL 79734 TOTAL 85331 227 211 771 501 239 130 91 69 59 52 63 107 64 49 47 S3 52 51 46 39 35 42 39 42 36 31 31 47 102 262 1070 4658 150 1070 31 9240 .75 .87 MEAN MEAN 1390 463 219 140 123 146 188 124 111 139 128 110 91 79 70 66 59 52 47 44 37 34 33 31 31 31 31 26 25 26 32 4126 133 1390 25 8180 .67 .77 218 MAX 234 MAX 37 28 28 31 597 824 337 231 126 88 92 314 1340 433 210 120 89 160 668 498 271 202 134 96 76 61 56 172 —— 7319 261 1340 28 14520 1.31 1.36 9890 NIN 17 9890 NIN 13 103 66 83 64 51 42 40 41 44 41 38 36 37 34 30 28 26 35 27 22 32 168 311 137 62 35 36 73 48 29 23 1842 59.4 311 22 3650 .30 .34 AC-PT AC-PT 26 36 41 23 22 23 28 30 36 28 27 32 59 42 331 192 61 38 28 26 26 26 27 28 46 48 31 30 30 29 —— 1450 48.3 331 22 2880 .24 .27 158200 169300 28 30 27 26 227 74 74 105 107 48 41 27 26 24 32 32 28 116 49 35 35 30 25 26 145 71 41 27 25 24 26 1631 52.6 227 24 3240 .26 .30 CPSN 1.09 CPSN 1.17 41 31 25 24 25 30 30 25 25 24 24 19 20 23 26 20 18 151 57 22 20 18 30 24 16 14 18 23 25 43 —— 891 29.7 151 14 1770 .15 .17 IN. 14.85 IN. 15.89 29 24 19 23 20 20 22 25 20 23 23 20 18 20 30 2020 1250 290 122 69 49 46 39 35 31 30 29 44 46 34 39 4509 145 2020 18 8940 .73 .84 47 31 25 22 89 51 23 19 20 19 19 18 18 18 17 17 33 25 16 16 42 51 22 14 14 17 130 70 20 16 17 956 30.8 130 14 1900 .15 .18 20 19 16 14 15 16 31 26 IS 15 13 13 14 17 18 20 28 23 16 13 13 14 19 16 19 18 18 29 33 35 —— 576 19.2 35 13 1140 .10 .11 141 RIO DB LA PLATA BASIN 50046000 RIO DB LA PLATA AT HWY 2 NR TOA ALTA, PR (National atrearn-quality accounting network atation) WATER-QUALITY RECORDS LOCATION.--Lat 18«24'41", long 66«15'39", at Highway 2, 1.3 mi (2.1 km) downatream from Rio Lajaa, and 1.6 mi (2.6 km) northweat of Toa Alta, 11.3 mi (18.2 km) downstream from Puerto Rico Aqueduct and Sewer Authority reaervoir. . DRAINAGE AREA.—208 mia (539 km3), exclude 8.2 mia (21.2 km3 ) upatream from Lago Carite, flow from which ia diverted to Rio Ouamani. PERIOD OF RECORD.—Water yeara 1958 to current year WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 09... DEC 19... FBB 1991 11... APR 04... JUN 06... AUQ 13... DATE OCT 1990 09... DEC 19... FEB 1991 11... APR 04... JUN 06... AUQ 13... TIME 0800 0900 1015 0830 1000 1230 CALCIUM DIS- SOLVED (MQ/L AS CA) 32 63 45 49 67 62 DIS- CHARGE, INST. CUBIC FEET PER SECOND 800 46 76 24 25 19 MAGNE- SIUM, DIS- SOLVED (MQ/L AS MQ) 10 12 11 9.9 13 13 SPE- CIFIC CON- DUCT- ANCE (US/CM) 302 470 410 396 499 484 SODIUM, DIS- SOLVED (MQ/L AS NA) 18 20 19 19 25 23 PH (STAND- ARD UNITS) 7.7 7.6 7.7 7.5 7.7 8.0 SODIUM AD- SORP- TION RATIO 0.7 0.6 0.7 0.6 0.7 0.7 TEMPER- ATURE WATER (DBG C) 27.0 25.0 25.0 25.5 27.5 31.0 POTAS- SIUM, DIS- SOLVED (MQ/L AS K) 3.9 2.6 2.6 2.8 2.2 2.5 TUR- BID- ITY (NTU) 28 2.9 6.4 4.0 1.8 2.0 ALKA- LINITY WAT WH TOT FBT FIELD MQ/L AS CACO3 110 180 150 150 200 180 OXYGEN, DIS- SOLVED (MQ/L) 4.8 6.4 6.5 3.4 5.3 9.2 SULFATB DIS- SOLVED (MQ/L AS 804) 17 23 25 14 18 19 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 60 76 77 41 66 122 CHLO- RIDE, DIS- SOLVED (MQ/L AS CL) 21 29 24 23 26 33 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 31000 K780 3500 300 270 30 FLUO- RIDE, DIS- SOLVED (MQ/L AS F) 0.10 0.30 0.10 0.20 0.20 0.10 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 5300 460 980 210 210 10 SILICA, DIS- SOLVED (MQ/L AS SI02) 19 18 18 15 19 18 HARD- NESS TOTAL (MQ/L AS CACO3) 120 210 160 160 220 210 SOLIDS, RESIDUE AT 180 DBG. C DIS- SOLVED (MQ/L) 190 275 227 227 300 279 DATE OCT 1990 09... DEC 19.. . FBB 1991 11... APR 04... JUN 06... AUQ 15... SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MQ/L) 189 280 237 227 293 279 SOLIDS, DIS- SOLVED (TONS PER DAY) 410 34.2 46.8 14.5 19.8 14.3 NITRO- GEN, NO2+N03 DIS- SOLVED (MQ/L AS N) 0.200 0.800 0.400 0.730 0.340 0.560 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS N) 0.060 0.210 0.090 0.120 0.030 0.040 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.08 0.27 0.12 0.15 0.04 0.05 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 0.40 0.30 0.50 0.70 0.70 PHOS- PHORUS TOTAL (MG/L AS P) 0.080 0.120 0.140 0.150 0.130 0.200 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.070 0.100 0.110 0.110 0.100 0.140 PHOS- PHORUS ORTHO, DIS- SOLVED (MQ/L AS P) 0.050 0.100 0.090 0.120 0.090 0.140 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS P04) 0.15 0.31 0.28 0.37 0.28 0.43 non-ideal count 142 RIO DB LA PLATA BASIN 50046000 RIO DB LA PLATA AT HOT 2 NR TOA ALTA, PR—Continued (National stream-quality accounting network station) WATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 09... DEC 19... FBB 1991 11... APR 04... JUN 06... AUG 13... DATE OCT 1990 09... DEC 19... FBB 1991 11... APR 04... JUN 06... ADO 13... DATE JUN 1991 06... DATE JUN 1991 06... DATE JUN 1991 06... ALUM- BERYL- CHRO- INUM, ARSENIC BARIUM, UUM, CADMIUM MIUM, CftBALT, COPPER, IRON, LEAD, DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED (UQ/L (UQ/L (UQ/L (UQ/L (UQ/L (UQ/L (UQ/L (UQ/L (UQ/L (UQ/L AS AL) AS AS) AS BA) AS BE) AS CD) AS CR) AS CO) AS CU) AS FB) AS PB) 110 1 49 <0.5 <1.0 7 <3 3 120 2 -- 60 1 45 <0.5 <1.0 <1 <3 3 11 1 __ <10 2 62 <0.5 <1.0 1 <3 4 10 2 <10 2 66 <0.5 <1.0 <1 <3 4 6 <1 MANOA- MOLYB- SELB- 8TRON- VANA- LITHIUM NBSB, MERCURY DBNUM, NICKEL, NIUM, SILVER, TIUM, DIUM, ZINC, DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED (UQ/L (UQ/L (UQ/L (UG/L (UQ/L (UQ/L (UQ/L (UG/L (UG/L (UG/L AS LI) AS MN) AS HO) AS MO) AS NI) AS SB) AS AQ) AS SR) AS V) AS ZN) <« 22 <0.1 <10 7 <1 <1.0 140 10 40 __ 5 81 <0.1 <10 1 <1 <1.0 180 6 13 -- <« 38 <0.1 <10 1 <1 <1.0 300 <6 15 <« 67 <0.1 <10 1 <1 <1.0 270 7 5 PESTICIDE ANALYSES CHLOR- DI- DI- BNDO- PCB, ALDRIN, DANE, ODD, DDE, DOT, AZINON, ELDRIN SULFAN, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UQ/L) (UG/L) (UG/L) (UQ/L) (UQ/L) (UQ/L) (UQ/L) (UG/L) (UG/L) 1000 <0.1 <0.010 <0.1 <0.010 <0.010 <0.010 0.04 <0.010 <0.010 HBPTA- METH- METHYL METHYL HEPTA- CHLOR MALA- OZY- PARA- TRI- BNDRIN, BTHION, CHLOR, EPOZIDE LINDANB THION, CHLOR, THION, THION, MIREX, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UQ/L) (UQ/L) (UQ/L) (UQ/L) (UQ/L) (UG/L) (UG/L) (UQ/L) (UQ/L) (UG/L) •cO.010 <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 <0.01 <0.01 NAPH- THA- LENES, PARA- POLY- PER- TOX- TOTAL THION, CHLOR. THANE APHENB, TRI- 2,4-D, 2,4,5-T 2, 4 -DP SILVBX, TOTAL TOTAL TOTAL TOTAL THION TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UQ/L) (UQ/L) (UG/L) (UQ/L) (UG/L) (UQ/L) (UQ/L) •cO.Ol <0.10 <0.1 <1 <0.01 0.01 <0.01 <0.01 <0.01 143 RIO DB LA PLATA BASIN 50046000 RIO DB LA PLATA AT HWY 2 MR TOA ALTA, PR—Continued (National stream-quality accounting network station) WATER-QUALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SBDIMBNT DATS OCT 1990 09... DBC 1991 19... PBB 11... APR 04... JTJN 06... AUQ 13... TIME 0800 0900 1015 0830 1000 1230 STREAM- FLOW, INSTAN- TANEOUS (CFS) 800 46 76 24 25 19 SEDI- MENT, SUS- PENDED (MG/L) 53 3.8 15 22 82 18 SBDI- MBNT, DIS- CHARGE, SUS- PENDED (T/DAY) 114 0.47 3.1 1.4 5.5 0.90 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 92 — 86 91 48 90 144 THIS PAGE WAS LEFT BLANK INTENTIONALLY ATLANTIC OCEAN k21B c^fkf> *^%K_ K 1s / \ r^' 1 ^-^ ) N¥l* / X-^ / W0488 w1 ? ^048770 /^"-\—i TRUJILtO <G \ / ^f \..U«. «WMM4 y»**««« * 8c*«« > ii EXPLANATION A 047560 SURFACE-WATER STATION AND NUMBER T 0476 QUALITY-OF-WATER STATION AND NUMBER • 220 WELL AND WELL NUMBER • 047550 LAKE-ELEVATION STATION 0123456 KILOMETERS I J_I__L^ _ ! _ ,L_J_ 01234 Figure 18.--Rfo Hondo to Rio Puerto Nuevo basins. 146 RIO HONDO BASIN 50047530 RIO HONDO AT FLOOD CHANNEL NEAR CATANO, PR MATBR-QDALITY RECORDS LOCATION.--Lat 18°26'13", long 66°09'36", at Rio Hondo Channel, 800 ft (245 m) below junction with Rio Hondo, 0.9 mi (1.5 km) downstream from bridge on de Diego Expressway and 1.1 mi (1.8 km) above mouth. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.—Mater years 1979 to current year. MATBR-QDALITY DATA, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 20... JAN 1991 04... MAR 01... MAY 07... JDN 26... ADO 26... TIME 0900 0750 0845 0815 0815 0820 DIS- CHARGE, INST. CUBIC FEET PER SECOND NF NF NF NF NF NF SPE- CIFIC CON- DUCT- ANCE (US/CM) 5340 6300 44200 2600 28800 17600 PH (STAND- ARD UNITS) 7.4 7.4 7.4 7.6 8.2 7.9 TEMPER- ATURE MATER (DBG C) 26.5 22.5 27.0 26.0 28.5 30.0 TUR- BID- ITY (NTU) 1.1 4.0 61 24 2.7 3.1 OXYGEN, DIS- SOLVED (MG/L) 2.5 7.5 7.3 4.6 8.5 2.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 30 29 90 56 96 32 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 48 58 53 44 450 340 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3600 K99000 K86000 20000 K6900 20000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K140 8900 43000 1500 K1600 7200 DATE NOV 1990 20... JAN 1991 04... MAR 01... MAY 07... JUN 26... AUQ 26... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL MH MAT DI6- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CAC03 MAGNE- SIUM, DI6- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 510 0 54 91 790 320 0 44 50 410 2100 2500 190 530 4400 SODIUM AD- SORP- TION RATIO ALKA- POTA6- UNITY CHLO- SIUM, MAT MH SULFATB RIDE, DIS- TOT PET SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 15 33 10 24 37 200 CACO3 87 150 57 110 150 160 AS S) AS 804) AS CL) <0.5 160 <0.5 100 1100 1500 700 8400 DATE NOV 1990 20... JAN 1991 04... MAR 01... MAY 07... JDN 26... AUG 26... NF - No flow K » non-ideal count FL0O- RIDB, DIS- SOLVED (MG/L AS F) 0.60 — — 0.20 — 1.5 SILICA, DIS- SOLVED (MG/L AS 8102) 6.1 — ~ 9.2 — 4.1 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 2690 — — 1400 — 14900 SOLIDS, DIS- SOLVED (TONS PER DAY) — — ~ ~ — — RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 21 17 58 27 22 32 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.340 0.130 0.340 0.530 0.090 0.180 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.060 0.070 0.030 0.070 0.070 0.060 NITRO- GEN, N02+NO3 TOTAL (MG/L AS N) 0.400 0.200 0.370 0.600 0.160 0.240 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.640 1.20 0.140 0.550 0.250 0.620 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.36 0.40 0.86 0.65 1.0 0.58 147 RIO HONDO BASIN 50047530 RIO HONDO AT FLOOD CHANNEL NEAR CATANO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 20... JAN 1991 04... MAR 01... MAY 07... JUN 26... AUQ 26... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.0 1.6 1.0 1.2 1.3 1.2 NITRO- GEN, TOTAL (MQ/L AS N) 1.4 1.8 1.4 1.8 1.5 1.4 NITRO- GEN, TOTAL (MG/L AS N03) 6.2 8.0 6.1 8.0 6.5 6.4 PHOS- PHORUS ARSENIC TOTAL TOTAL (MQ/L (UQ/L AS P) AS AS) 0.200 1 0.280 0.090 0.160 1 0.210 0.210 BARIUM, TOTAL RECOV- ERABLE (UQ/L AS BA) <100 — — <100 — — BORON, TOTAL RECOV- ERABLE (UQ/L AS B) 410 -- __ 200 -- — CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — — CHRO- MIUM, COPPER, TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLE (UG/L (UQ/L AS CR) AS CD) 1 20 __ __ 1 20 __ __ DATE NOV 1990 20... JAN 1991 04... MAR 01... MAY 07... JUN 26... AUQ 26... IRON, TOTAL RECOV- ERABLE (UG/L AS PB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UQ/L AS HQ) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AQ) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MQ/L AS CN) PHENOLS TOTAL (UQ/L) MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MQ/L) 820 1500 230 190 <0.20 <0.10 20 <0.010 <0.010 0.29 0.17 148 RIO DB BAYAMON BASIN 50047550 LACK) CIDRA AT DAMSITE NEAR CIDRA, PR LOCATION.—Lat 18«11'57-, long 66°08'29 1> , Hydrologie Unit 21010005, at Lago de Cidra Dam on Rfo de Bayamon, 1.9 ml (3.0 km) northeast of Plaza da Cidra and 1.8 ml (2.9 km) northwest of Bseuela Segunda Unidad da Bayam6n. DRAINAGE AREA.--8.26 ml* (21.39 km*). ELEVATION RECORDS PERIOD OF RECORD.—January 1988 to currant year. GAGE.—Water-stag* recorder. Datum of gaga is mean sea level. REMARKS.—Lago de Cidra was completed in 1946. The »Mi»™ storage is 5,300 ae-ft (6.53 hm3 ) and provides supple- mental water to metropolitan San Juan. The dam is a concrete gravity and earthfill structure approximately 541 ft (165 m) long between abutments with a maximum structural height of about 78.7 ft (24.0 m). The spillway portion of the dam, length 131 ft (40 m) and crest elevation 1,322 ft (403 m), is an ungated ogee crest located 131 ft (40 m) from the right abutment. This dam is owned by Puerto Rico Aqueduct and Sewer Authority. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.—Maximum elevation 1,323.99 ft (403.55 m), Feb. 3, 1988; minimum elevation 1.305.18 ft (397.82 m), Sept. 30, 1990. EXTREMES OBSERVED FOR CURRENT YBAR.—Maximum elevation, 1,323.39 ft (403.37 m), Feb. 5; minimum elevation, 1.305.19 ft (397.82 m), Oct. 1. Capacity Table (based on data from Puerto Rico Electric Power Authority) Elevation, in feet 1,305 1,309 1,312 Contents, in acre-feet 1,970 2,610 3,100 Elevation, in feet 1,319 1,322 1,324 Contents, in acre-feet 4,400 5,200 5,800 DAY ELEVATION (FEET NGVD), WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY OBSERVATION AT 24tOO VALUES OCT NOV DEC 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 1305.20 1305.21 1305.23 1305.24 1305.26 1305.27 1305.26 1305.28 1305.50 1305.72 1305.96 1306.16 1306.52 1307.01 1308.20 1309.16 1309.47 1311.16 1312.46 1312.73 1316.38 1316.67 1316.82 1317.02 1317.61 1319.09 1319.54 1319.68 1319.77 1319.85 1319.93 1311.11 1319.93 1305.20 1320.01 1320.08 1320.14 1320.08 1320.02 1319.94 1319.87 1319.84 1319.80 1319.76 1319.70 1319.64 1319.56 1319.44 1319.32 1319.22 1319.12 1318.98 1318.84 1318.74 1318.63 1318.62 1318.57 1318.50 1318.41 1318.38 1318.34 1318.40 1318.56 1318.74 —— 1319.24 1320.14 1318.34 1318.94 1319.04 1319.32 1319.44 1319.53 1319.59 1319.62 1319.64 1319.68 1319.71 1319.74 1319.77 1319.79 1319.82 1319.85 1319.87 1319.89 1319.90 1319.93 A A A A A ___ JAN FBB MAR APR MAY JUN JUL AUG SEP A A A A A A A A A A A A A A A A A A A A A A 1322.77 1322.78 1322.79 1322.77 1322.75 1322.72 1322.72 1322.69 1322.71 —— 1322.70 1322.71 1322.69 1322.74 1323.39 1322.87 1322.65 1322.55 1322.49 1322.45 1322.54 1322.98 1322.80 1322.64 1322.56 1322.52 1322.46 1322.53 1322.57 1322.56 1322.55 1322.53 1322.51 1322.51 1322.48 1322.43 1322.44 1322.44 --_ —— 1322.62 1323.39 1322.43 1322.47 1322.47 1322.49 1322.53 1322.55 1322.58 1322.60 1322.62 1322.58 1322.46 1322.39 1322.29 1322.21 1322.12 1322.03 1321.94 1321.85 1321.83 1321.75 1321.66 1321.58 1321.82 1321.88 1321.90 1321.91 1321.92 1321.91 1321.89 1321.87 1321.85 1321.81 1322.12 1322.62 1321.58 1321.77 1321.75 1321.73 1321.71 1321.67 1321.65 1321.61 1321.61 1321.59 1321.61 1321.58 1321.60 1321.62 1321.60 1321.58 1321.58 1321.56 1321.54 1321.51 1321.47 1321.43 1321.38 1321.34 1321.27 1321.23 1321.15 1321.09 1321.04 1320.97 1320.91 1321.47 1321.77 1320.91 1320.86 1320.82 1320.75 1320.69 1320.63 1320.59 1320.55 1320.54 1320.50 1320.45 1320.40 1320.42 1320.42 1320.36 1320.32 1320.26 1320.18 1320.14 1320.06 1320.00 1319.94 1319.85 1319.75 1319.66 1319.90 1319.90 1319.86 1319.82 1319.74 1319.65 1319.60 1320.21 1320.86 1319.60 1319.52 1319.42 1319.32 1319.26 1319.16 1319.09 1319.00 1318.91 1318.81 1318.68 1318.58 1318.48 1318.42 1318.34 1318.24 1318.11 1317.96 1317.86 1317.76 1317.65 1317.55 1317.44 1317.40 1317.30 1317.17 1317.06 1316.96 1316.80 1316.71 1316.80 —— 1318.13 1319.52 1316.71 1316.85 1316.88 1316.82 1316.76 1316.65 1316.54 1316.45 1316.37 1316.25 1316.12 1316.01 1315.88 1315.75 1315.64 1315.81 1316.90 1316.91 1316.89 1316.85 1316.75 1316.62 1316.53 1316.48 1316.44 1316.34 1316.21 1316.11 1316.03 1315.92 1315.87 1315.75 1316.37 1316.91 1315.64 1315.62 1315.56 1315.45 1315.34 1315.22 1315.11 1314.99 1314.88 1314.75 1314.64 1314.54 1314.42 1314.24 1313.95 1313.64 1313.36 1313.17 1313.06 1312.79 1312.49 1312.22 1312.48 1312.32 1312.06 1311.89 1311.67 1311.70 1311.72 1311.73 1311.61 1311.50 1313.49 1315.62 1311.50 1311.40 1311.26 1311.12 1311.03 1310.90 1310.78 1310.67 1310.56 1310.46 1310.35 1310.25 1310.19 1310.03 1309.91 1309.76 1309.62 A A A A A A A A A A A A A A —— —— No gage-height record. RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO CIDRA, PR 149 LOCATION.—Lat 18°12'04", long 66°08'26 B , Hydrologic Unit 21010005, 0.2 mi (0.3 km) downstream of Lago Cidra Dam on right bank, 2.1 mi (3.4 km) northweit of Plaza de Cidra. DRAINAGB ARBA.--8.31 mi* (21.5 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—November 1990 to September 1991. GAGB.—Water-itage recorder. Blevation of gage 1m 1,279 ft (390 m), from topographic map. REMARKS.—Record! poor. Regulation al all itagei by Puerto Rico Aqueduct and Sewer Authority reiervoir upitream from gage. Gage-height and precipitation Mtellite telemetry at itation. EXTREMES FOR CURRENT PERIOD.--Maximun discharge, 532 ft3/" (15.1 **/•), Feb. 5, gage-height, 12.32 ft (3.755 m), from rating curve extended above 50 ft3/* (1.42 mV") on baiii of itep-backwater analytic* minimun daily discharge, 9.4 ft'/« (0.266 m'/«). July 17. DISCHARGE, CUBIC FEET PER SECOND, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 13 12 13 28 28 28 26 28 28 29 29 29 52 60 60 62 e55 e55 060 060 055 060 060 060 055 055 055 035 013 012 1215 40.5 62 12 2410 4.87 5.43 012 013 013 013 13 13 13 13 13 13 13 12 13 13 12 12 12 12 11 11 12 12 12 12 11 10 11 11 12 12 20 385 12.4 20 10 764 1.49 1.72 12 20 18 16 16 16 16 18 19 19 18 17 15 15 16 15 15 14 14 12 12 12 12 12 13 13 13 13 14 14 14 463 14.9 20 12 918 1.80 2.07 14 13 12 13 143 193 73 38 25 17 30 64 120 50 26 17 13 14 20 19 18 16 15 14 14 11 10 11 —— 1023 36.5 193 10 2030 4.39 4.57 12 13 13 17 16 17 18 19 19 14 11 11 11 11 12 12 12 13 13 13 13 14 13 13 13 12 12 12 12 11 12 414 13.4 19 11 821 1.61 1.85 11 11 11 10 10 12 12 12 12 12 12 12 13 13 13 12 13 13 12 12 13 13 13 13 13 13 13 13 13 12 —— 367 12.2 13 10 728 1.47 1.64 13 13 13 13 13 13 14 14 13 11 11 11 11 11 11 11 12 12 11 12 11 12 12 12 15 12 11 12 13 12 12 377 12.2 15 11 748 1.46 1.69 13 13 13 13 13 13 12 12 12 12 12 12 13 13 12 12 11 12 12 12 12 12 12 12 12 11 11 11 12 12 —— 364 12.1 13 11 722 1.46 1.63 11 11 11 11 11 11 11 11 11 11 11 11 10 11 14 21 9.4 9.5 10 11 11 11 11 11 11 12 14 13 14 13 13 361.9 11.7 21 9.4 718 1.40 1.62 14 14 15 16 15 16 16 17 16 17 17 19 30 49 49 41 23 18 47 45 46 55 43 37 37 28 24 20 29 26 14 853 27.5 55 14 1690 3.31 3.81 13 14 13 13 12 12 11 12 12 12 12 32 23 11 12 12 26 14 15 15 16 17 17 18 18 18 19 20 20 21 480 16.0 32 11 952 1.92 2.15 Bitimated 150 RIO DB BAYAMON BASIN 50047600 RIO DB BAYAMON NEAR AGH7AS BUBNAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°14'39', long 66°08'39", at bridge on Highway 156, and 2.9 ml (4.7 km) west of Aguas Buenas plaza. DRAINAOB AREA.—18.5 mi* (47.9 k*1 ) . PERIOD Or RECORD.—Water years 1958-65, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 17... DEC 18... FEB 1991 13... APR 26... JUN 18... ADO 14... TIKE 1245 1045 0915 0950 1315 1345 DIS- CHARGE, INST. CUBIC FEET PER SECOND 33 18 89 19 18 38 SPE- CIFIC CON- DUCT- ANCE (US /CM) 237 265 233 286 291 270 PH (STAND- ARD UNITS) 8.0 8.1 8.0 8.0 8.5 8.3 TEMPER- ATURE WATER (DBG C) 24.5 22.0 22.0 24.0 26.5 26.0 TUR- BID- ITY (NTU) 55 6.6 17 3.0 3.2 36 OXYGEN, DIS- SOLVED (MQ/L) 7.6 8.4 8.2 7.3 8.2 6.7 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 93 98 94 87 103 83 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 27 <10 16 13 <10 21 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3900 510 K1700 K130 K180 270 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 2800 990 3400 250 500 750 DATE OCT 1990 17... DEC 18... FEB 1991 13... APR 26... •TON 18... AUG 14... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CACO3) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 88 0 20 9.2 12 110 1 26 10 16 98 0 23 9.9 20 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT FBT SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.6 3.6 0.7 1.8 0.9 2.3 CACO3 69 100 85 110 120 97 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS S04) AS CL) <0.5 9.8 /s), Aug. 11, 13. DISCHARGE, CUBIC FEET PBR SECOND, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SBP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 2C 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 14 7.5 99 80 46 25 65 41 110 158 5C 15 9.7 9.9 9.5 11 202 170 54 45 207 26 15 53 103 C3 20 15 14 21 11 1775. C 57.3 207 7.5 3520 7.C5 8.82 1990 1991 10 8.3 8.3 7.8 7.4 7.7 9.5 8.0 C.7 7.5 C.4 C.3 5.8 5.9 C.4 5.2 C.2 5.3 5.4 C.2 5.4 5.3 4.7 4.8 4.3 11 11 C.4 20 12—— 225.2 7.51 20 4.3 447 1.00 1.12 TOTAL 5905 TOTAL C242 37 18 49 12 7.7 6.5 5.1 4.9 4.8 5.2 7.2 5.2 5.7 6.C 7.8 9.6 C.O 5.7 5.4 5.5 C.4 C.8 7.9 8.8 7.3 7.9 7.3 22 54 34 142 519.3 1C. 8 142 4.8 1030 2.24 2.58 .8 MEAN .C MEAN C7 34 17 13 12 14 14 9.1 11 12 9.0 21 9.4 9.2 9.0 8.9 9.2 8.5 8.4 7.6 8.1 7.8 8.3 7.1 7.C 7.0 7.0 6.C 6.2 5.4 8.4 382.8 12.3 C7 5.4 759 1.C5 1.90 1C. 2 MAX 17.1 MAX C.I C.4 6.4 5.7 133 37 18 9.8 8.4 7.2 18 11 10 9.3 8.4 8.0 7.C 93 78 80 29 19 11 10 8.9 8.0 7.0 7.0 —— 6C1.2 23. C 133 5.7 1310 3.15 3.28 207 MIN 207 MIN 6.1 6.0 6.0 8.1 8.7 8.7 7.7 C.9 C.I C.9 C.5 C.I C.I 7.3 7.3 C.9 C.8 8.2 7.3 7.C 8.C 73 13 8.8 8.1 7.4 C.C 6.7 C.3 5.9 C.9 292. C 9.44 73 5.9 580 1.2C 1.45 3.2 AC-FT 2.5 AC-FT C.I 24 10 C.3 5.2 5.3 4.7 2C 7.9 7.1 9.2 25 19 9.2 30 12 7.8 .2 .9 .9 .7 .4 5.7 C.C 14 7.C 7.2 C.I C.3 eC.4 —— 310.8 10.4 30 4.7 C16 1.38 1.54 11710 12380 e6.C •7.5 e20 •90 •25 •15 •21 •14 •20 3C 15 9.2 11 8.7 8.3 10 7.4 35 15 C3 13 9.2 6.8 C.I 9.6 •18 •12 •5.3 •5.2 •5.0 e5.2 533.1 17.2 90 5.0 10CO 2.30 2.C5 CFSM 2. 1C CFSM 2.28 •5.2 •5.0 •5.0 eC.4 eC.O •5.4 e5.4 eC.O e5.4 •5.4 •C.4 eC.O eC.C •7.2 eC.O eC.C eC.7 •42 •14 eC2 •25 ell •7.4 eC.l •5.1 e5.2 •4.3 e4.2 •4.2 ell—— 302.2 10.1 C2 4.2 599 1.34 1.50 IN. 29 IN. 31 e4.4 •3.8 e4.5 e3.8 e3.4 •3.3 •4.2 eC.l e4.8 •4.2 •C.9 •C.2 e3.8 e4.5 •66 •91 •13 •6.4 4.C 3.8 3.0 3.4 3.4 3.8 e3.4 e4.8 e4.3 el!9 •15 e8.4 4.C 420.2 13. C 119 3.0 833 1.81 2.89 .33 .00 3.4 5.7 3.8 4.5 13 4.1 3.2 2.9 2.7 2.C 2.5 2.C 2.5 2.9 •3.2 e77 eCl 15 4.9 33 145 •39 •14 eC.l •4.3 e3.C •99 •30 •9.0 •5.0 •7.0 C12.5 19.8 145 2.5 1210 2.C4 3.04 •6.0 e4.0 •3.5 •3.5 •3.5 e4.0 •20 elO •6.0 •3.5 •3.7 •3.5 •3.1 •3.1 •3.5 •4.5 15 3.9 3.2 3.2 3.5 8.4 3.2 3.2 2.8 3.0 23 7.3 2C 1C—— 207.1 C.90 2C 2.8 411 .92 1.03 Estimated 159 RIO PUERTO NUBVO BASIN 50048770 RIO PIBDRAS AT BL SBNORIAL, PR--Continued MATER QUALITY RBCORDS PERIOD OF RECORD.-- OCTOBER 1989 TO CURRENT YBAR STRRAMFLOW, SPECIFIC CON- TEMPERA- STRRAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCB TURB DATE TINS INSTANTANEOUS DUCTANCB TORE (CFS) (UlffiOS) (DBQ C) (CFS) (UMHOS) (DBG C) OCT. 10 1319 8.86 120 25.5 AUG. 16 1045 3.27 400 27.0 NOV. 26 1553 10.4 347 26.5 SEP. 10 1508 4.11 410 27.0 FEB. 27 1243 8.64 418 28.0 160 RIO PUERTO NUBVO BASIN 50048770 RIO PIEDRAS AT EL SBNORIAL, PR--Continued HATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1988 to current year. INSTRUMENTATION.— USD-77 and automatic •ediment •ampler. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE! April 1988 to September 1990. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION! Maximum daily mean, 24,600 B0/L Sep. 18, 1989; Minimum daily mean, 2 B0/L November 18, 1988. SEDIMENT LOADS! Maximum daily mean, 96,700tons (88,000tonnes) Sep. 18, 1989; Minimum daily mean, 0.04 ton (0.03 tonne) May 6, 1990. EXTREMES FOR HATER YEAR 1991.-- SEDIMENT CONCENTRATION! Maximum daily mean, 3,920 mo/L Aug. 21, 1991; Minimum daily mean, 6 m0/l several days. SEDIMENT LOADS« Maximum daily mean, 8,310 tons (7,540 tonnes) Oct. 17, 1990; Minimum daily mean, 0.04 ton (0.03 tonne) several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MQ/L) (TONS/DAY) DECEMBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 14 7.5 99 80 46 25 65 41 110 158 56 15 9.7 9.9 9.5 11 202 170 54 45 207 26 15 53 103 63 20 15 14 21 11 20 20 3080 2680 314 156 1620 351 2740 2850 839 87 47 39 42 32 3330 1730 630 1030 3700 452 260 855 1050 562 360 79 75 306 55 .76 .39 1180 1200 44 13 878 50 4070 4240 327 3.8 1.3 1.1 1.0 .83 8310 1810 156 412 4330 34 11 613 1020 246 16 3.2 2.9 56 1.7 10 8.3 8.3 7.8 7.4 7.7 9.5 8.0 6.7 7.5 6.4 6.3 5.8 5.9 6.4 5.2 6.2 5.3 5.4 6.2 5.4 5.3 4.7 4.8 4.3 11 11 6.4 20 12 43 90 70 60 59 51 25 19 17 17 18 18 35 24 20 20 19 18 16 16 16 16 16 16 15 69 75 27 204 87 1.1 2.0 1.6 1.3 1.1 1.1 .69 .41 .33 .35 .32 .32 .54 .39 .32 .27 .31 .24 .24 .27 .23 .25 .21 .19 .17 3.3 4.0 .48 82 6.1 37 18 49 12 7.7 6.5 5.1 4.9 4.8 5.2 7.2 5.2 5.7 6.6 7.8 9.6 6.0 5.7 5.4 5.5 6.4 6.8 7.9 8.8 7.3 7.9 7.3 22 54 34 142 458 118 648 86 45 31 27 23 20 19 45 19 16 17 20 53 14 10 9 9 9 10 43 51 14 10 22 250 926 345 2270 130 11 236 2.8 .86 .52 .39 .27 .26 .26 3.8 .27 .23 .29 .42 2.6 .22 .15 .12 .13 .15 .18 1.5 .29 .29 .20 1.4 58 581 68 1570 TOTAL 1775.6 29032.98 225.2 110.13 519.3 2671.42 161 RIO PUERTO NUEVO BASIN 50048770 RIO PIBORAS AT BL SBNORIAL, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 67 34 17 13 12 14 14 9.1 11 12 9.0 21 9.4 9.2 9.0 8.9 9.2 8.5 8.4 7.6 8.1 7.8 8.3 7.1 7.6 7.0 7.0 6.6 6.2 5.4 8.4 675 154 57 31 24 48 54 40 45 53 32 248 37 27 17 14 11 10 10 10 10 9 9 8 8 8 8 6 5 5 10 132 17 2.7 1.1 .67 2.5 2.8 .99 1.5 2.6 .84 105 .95 .66 .39 .33 .28 .23 .23 .21 .23 .18 .21 .17 .16 .15 .15 .11 .10 .08 .22 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MQ/L) (TONS/DAY) FEBRUARY MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 6.1 6.4 6.4 5.7 133 37 18 9.8 8.4 7.2 18 11 10 9.3 8.4 8.0 7.6 93 78 80 29 19 11 10 8.9 8.0 7.0 7.0 10 10 10 10 2160 530 150 41 40 25 165 74 18 14 11 10 10 823 1280 1500 192 119 53 48 40 36 30 22 .16 .18 .18 .16 6420 174 9.8 1.1 .90 .49 34 2.2 .48 .34 .25 .22 .20 979 444 643 15 6.1 1.6 1.3 .96 .78 .56 .41 6.1 6.0 6.0 8.1 8.7 8.7 7.7 6.9 6.1 6.9 6.5 6.1 6.1 7.3 7.3 6.9 6.8 8.2 7.3 7.6 8.6 73 13 8.8 8.1 7.4 6.6 6.7 6.3 5.9 6.9 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 26 2240 69 42 30 36 28 19 17 16 20 .36 .34 .33 .34 .35 .38 .33 .29 .28 .29 .31 .30 .29 .34 .36 .34 .35 .41 .42 .43 .59 1690 2.6 1.1 .68 .69 .56 .36 .30 .25 .38 TOTAL 382.8 274.74 661.2 8737.37 292.6 1704.35 162 RIO PUERTO NDBVO BASIN 50048770 RIO PIHDRAB AT EL SBNORIAIi, PR--Continued SBDIMENT DISCHARGDB, SO8PBNDBD (TONS/DAY), WATER TEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN CONCBN- SBDIMENT TRATION DISCHARGDB (MG/L) (TONS/DAY) APRIL MEAN DISCHARGE (CFS) €.1 24 10 €.3 5.2 5.3 4.7 26 7.9 7.1 9.2 25 19 9.2 30 12 7.8 9.2 €.9 €.9 €.7 €.4 5.7 €.6 14 7.6 7.2 €.1 €.3 •6.4 27 248 42 20 20 20 20 257 34 22 25 414 158 34 311 €1 19 10 8 8 8 8 8 8 86 20 10 10 10 •10 .48 €0 1.3 .33 .29 .28 .25 46 .75 .41 .62 273 23 .88 €1 2.3 .41 .26 .14 .16 .14 .13 .12 .16 8.3 .42 .20 .17 .17 • .17 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MAY •6.6 •7.5 •20 •90 •25 •15 •21 •14 •20 36 15 9.2 11 8.7 8.3 10 7.4 35 15 63 13 9.2 6.8 6.1 9.6 •18 •12 •5.3 •5.2 •5.0 •5.2 •10 •10 •48 •1200 •150 •82 •140 •179 •674 496 89 51 71 34 20 20 19 465 108 745 80 46 22 25 53 •164 •42 •16 •11 •10 •9 • .18 • .20 •2.6 •292 •10 •3.3 •14 •12 •90 199 4.1 1.6 2.6 .80 .44 .51 .36 180 9.0 535 4.0 1.7 .39 .47 1.9 •30 •1.5 • .26 • .17 • .15 • .13 TOTAL 310.8 481.84 533.1 1398.36 MEAN DISCHARGE (CFS) •5.2 •5.0 •5.0 •6.4 •6.0 •5.4 •5.4 •6.0 •5.4 •5.4 •6.4 •6.0 •6.6 •7.2 •6.0 •6.6 •6.7 •42 •14 •62 •25 •11 •7.4 •6.1 •5.1 •5.2 •4.3 •4.2 •4.2 •11 302.2 MEAN CONCEH- SEDIMENT TRATION DISCHARGDB (MG/L) (TONS/DAY) JUNE •9 •10 •11 •15 •20 •22 •22 •21 •19 •16 •11 •11 •11 •10 •10 •10 •10 •1810 •89 •791 •282 •65 •18 •18 •18 •18 •19 •27 •26 •78 .13 .13 .17 .25 .31 .34 .32 .34 .27 .23 .18 .17 .19 .21 .14 .17 .18 •1800 •3.7 •505 •70 •2.7 .36 .27 .26 .25 .23 .29 .31 •6.8 2393.90 • Estimated 163 RIO PUERTO NUBVO BASIN 50048770 RIO PIBDRAS AT EL SENORIAL, PR—Continued SBDIMBNT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY MEAN DISCHARGE (CPS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MEAN DISCHARGE (CFS) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL •4.4 •3.8 •4.5 •3.8 •3.4 •3.3 •4.2 6.1 4.0 4.2 6.9 6.2 3.8 •4.5 166 •91 •13 •6.4 4.6 3.8 3.0 3.4 3.4 3.8 •3.4 •4.0 •4.3 •119 •15 •8.4 4.6 420.2 JULY •21 •16 •25 •10 •10 •10 •10 •29 •18 •20 •20 •20 •20 •20 •2910 •1100 •94 •78 65 51 42 26 21 15 •13 •10 •10 •2010 •80 •48 18 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) AUGUST MEAN DISCHARGE (CFS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) YEAR 6242.6 • Estimated .27 .18 .61 .11 .09 .09 .11 .86 .20 .23 .39 .31 .18 .23 •2630 •814 •3.3 •1.3 .72 .38 .34 .22 .19 .18 • .11 • .11 • .12 •3830 •4.9 •3.2 .23 7293.16 64780.98 3.4 5.7 3.8 4.5 13 4.1 3.2 2.9 2.7 2.6 2.5 2.6 2.5 2.9 •3.2 •77 •61 15 4.9 33 145 •39 •14 •6.1 •4.3 •3.6 •99 •30 •9.0 •5.0 •7.0 18 34 17 20 135 32 19 95 10 9 7 6 6 10 •10 •1060 •770 84 21 500 3920 •357 •75 •22 •6 •11 •1850 •401 •57 •31 •39 .16 1.2 .21 .38 24 .40 .15 .77 .08 .07 .05 .04 .04 .14 • .09 •1350 •676 4.5 .30 215 6650 •57 •3.2 • .42 • .07 • .11 •1270 •60 •1.5 • .44 •1.9 612.5 10318.22 •6.0 •4.0 •3.5 •3.5 •3.5 •4.0 •20 •10 •6.0 •3.5 •3.7 •3.5 •3.1 •3.1 •3.5 •4.5 15 3.9 3.2 3.2 3.5 8.4 3.2 3.2 2.8 3.0 23 7.3 26 16 SEPTEMBER •60 •9 •12 •11 •6 •6 •243 •17 •24 •11 •17 •21 •16 •14 •7 •17 139 20 10 13 12 61 7 6 6 5 360 19 228 117 •4.5 • .11 • .12 • .10 • .06 • .07 •67• .41 • .40 • .11 • .34 • .26 • .22 • .20 • .08 • .28 21 .34 .19 .17 .16 6.8 .07 .06 .04 200 .04 > .38 207.1 48 13 364.51 164 RIO PUERTO NDBVO BASIN 50048770 RIO PIBDRA8 AT EL SENORIAL, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 PARTICLE-SIZE DISTRIBUTION OF SUSPBNDBD SEDIMENT DATE OCT 1990 09... 17... 18... 21... FBB 1991 18... MAR 22... JUN 18... DATE OCT 1990 09... 17... 18... 21... FBB 1991 18... MAR 22... JUN 18... TIME 1725 1440 1920 0030 2035 0820 1455 SBD. SUSP. FALL DIAM. PBRCBNT FINER THAN .016 MM 42 47 -- 31 59 61 56 DIS- CHARGE, INST. CUBIC FEET PER SECOND 769 949 162 607 187 524 402 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .031 MM 56 55 -- 38 71 75 67 SEDI- MENT, SUS- PBNDBD (MO/L) 8790 30200 2300 17200 12400 28200 79400 SBD. SUSP. SIEVE DIAM. PBRCBNT FINER THAN .062 MM 70 65 86 51 86 89 83 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 18200 77400 1100 28200 6260 40500 86200 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 80 73 91 64 92 94 90 SBD. SUSP. FALL DIAM. PBRCBNT FINER THAN .002 MM 8 19— 11 27 27 20 SBD. SUSP. SIEVE DIAM. PBRCBNT FINER THAN .250 MM 90 86 98 84 97 98 96 SBD. SUSP. FALL DIAM. PBRCBNT FINER THAN .004 MM 18 27 -- 17 35 37 28 SBD. SUSP. SIEVE DIAM. PBRCBNT FINER THAN .500 MM 97 98 100 98 99 100 99 SBD. SUSP. FALL DIAM. PBRCBNT FINER THAN .008 MM 30 38— 23 41 50 42 SED. SUSP. SIEVE DIAM. PBRCBNT FINER THAN 1.00 MM 100 100 100 100 100 100 100 165 RIO POBRTO NOBVO BASIN 50048770 RIO PIBDRAS AT EL SBNORIAL, PR--Continued HATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OF SOSPBNDBD SEDIMENT DATE OCT 1990 04... 09... 10... 10.. 17... 17... 18... 18... 20... 21... 24... 24... 24... FEB 1991 21... MAR 14... 22... 22... 22... JUN 18... JUL 15... 15... AUQ 16... 21... 21... TIME 1735 1655 1245 1350 1450 1800 1450 1720 2105 0315 2240 2310 2325 1229 1253 0742 0910 1145 1545 1725 2025 1245 1355 1725 STREAM- FLOW, INSTAN- TANEOUS (CFS) 226 574 425 1050 1600 286 320 405 152 221 246 213 195 7.2 8 187 212 125 212 277 6480 184 198 438 SEDI- MENT, SOS- PBNDBD (MQ/L) 13500 25400 16490 16800 42200 17100 2440 1020 14400 1140 1800 1300 1000 300 30 2660 8000 5600 8300 8460 6480 7500 7240 8210 SEDI- MENT, DIS- CHARGE, SOS- PBNDBD (T/DAY) 8240 39400 18900 47630 182300 13200 2110 1120 5910 680 1200 750 530 5.8 0.65 1340 4580 1890 4750 6330 113000 3730 3870 9710 SBD. SOSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 88 57 45 29 50 98 67 86 98 66 83 83 93 99 87 58 95 96 88 81 87 81 67 52 166 RIO PUERTO NDBVO BASIN 50048800 RIO PIEDRAS NEAR RIO PIBDRAS, PR MATER-QUALITY RECORDS LOCATION.--Lat 18°22'15", long 66°03'40", at bridge on Winston Churchill Avenue in the El Sefiorial Housing area, 0.5 ai (0.8 km) west of Highway 176, and 2.5 ai (4.0 km) southwest of Rfo Piedras plaia. DRAINAOE AREA.--8.17 ai2 (20.9 ka2 ) . PERIOD OF RECORD.—Water year* 1972 to current year. HATER QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 30... DEC 11... FEB 1991 15... APR 17... JUN 21... AUQ 02... TIHE 1025 1305 0830 1035 0905 1230 DIS- CHARGE, INST. CUBIC FEET PER SECOND 12 7.7 7.8 4.1 6.5 4.3 SPE- CIFIC CON- DUCT- ANCE (US /CM) 432 451 505 427 360 423 PH (STAND- ARD UNITS) 7.6 7.5 7.8 7.7 7.9 8.1 TEMPER- ATURE HATER (DBG C) 27.0 27.5 23.5 26.5 24.5 29.0 TUR- BID- ITY (NTU) 7.5 3.2 5.2 4.0 86 5.4 OXYGEN, DIS- SOLVED (MG/L) 4.2 3.8 5.2 6.9 7.5 7.8 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 52 25 61 85 90 99 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 61 48 67 26 26 12 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K1000000 K960000 K40000 250000 320000 4700 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 240000 260000 K70000 59000 35000 6000 DATE OCT 1990 30... DEC 11... FEB 1991 15... APR 17... JUN 21... AUG 02... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS CAC03) CAC03 MQ/L AS (MQ/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L AS CA) AS MO) AS NA) 140 0 35 12 27 140 0 38 12 28 150 1 40 13 27 SODIUM AD- SORP- TION (MQ/L RATIO ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATB RIDE, DIS- TOT PET SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MQ/L MQ/L AS (MG/L AS K) 3.5 3.5 0.9 2.9 CACO3 150 160 170 155 120 150 (MG/L <0.5 25 <0.5 15 18 (MG/L AS S) AS SO4) AS CD 29 33 33 SOLIDS, DATE OCT 1990 30... DEC 11... FEB 1991 15... APR 17... JUN 21... AUG 02... FLUO- RIDE, DIS- SOLVED (MQ/L AS F) 0.40 __ -- <0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SIO2) 31 — — 30 — 31 SUM OF CONSTI- TUENTS, DIS- SOLVED (MQ/L) 253 __ __ 252 -- 255 RESIDUE SOLIDS, TOTAL NITRO- NTTRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL PER PENDBD (MQ/L (MQ/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 22 10 13 1 95 1 0.550 0.320 0.450 0.590 0.820 0.510 0.050 0.080 0.050 0.140 0.060 0.040 0.600 0.400 0.500 0.730 0.880 0.550 1.80 2.60 7.70 2.50 0.420 0.190 2.1 2.1 1.7 1.3 0.48 0.31 non-ideal count 167 RIO PUHRTO NUBVO BASIN 50048800 RIO PIBDRAS NBAR RIO PIBDRAS, PR—Continued HATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 30... DBC 11... FBB 1991 15... APR 17... JUN 21... AUG 02... DATE OCT 1990 30... DBC 11... FBB 1991 15... APR 17... JUN 21... AUG 02... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 3.9 4.7 9.4 3.8 0.90 0.50 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 4.5 5.1 9.9 4.5 1.8 1.0 LEAD, TOTAL RECOV- ERABLE (UQ/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 20 23 44 20 7.9 4.6 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MQ/L AS P) 0.940 1.40 1.10 0.450 0.190 0.160 MERCURY TOTAL RECOV- ERABLE (UG/L AS HO) ARSENIC TOTAL (UG/L AS AS) 1 — — 2 -- — SELE- NIUM, TOTAL (UQ/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 — — 100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AQ) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 40 — — 20 — -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 ~ — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 1 — -- <1 — -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 20 — — 10 — ~ MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MQ/L) 370 470 200 240 0.30 <0.10 <1 <1 <1 <1 10 <0.010 <0.010 1.1 0.25 PESTICIDE ANALYSES DATE JUN 1991 21... DATE JUN 1991 21... TIME 0905 TOTAL (UG/L) tO.010 PCB, TOTAL (UG/L) <0.1 ETHION, TOTAL (UG/L) ALDRIN, TOTAL (UG/L) <0.010 HBPTA- CHLOR, TOTAL (UG/L) CHLOR- DANB, TOTAL (UQ/L) <0.1 HBPTA- CHLOR EPOXIDB TOTAL (UG/L) DDD, TOTAL (UG/L) < 0.010 LINDANB TOTAL (UG/L) DDB, TOTAL (UG/L) <0.010 MALA- THION, TOTAL (UG/L) DOT, TOTAL (UG/L) <0.010 MBTH- OXY- CHLOR, TOTAL (UG/L) DI- AZINON, TOTAL (UG/L) 0.05 METHYL PARA- THION, TOTAL (UG/L) DI- BLDRIN TOTAL (UG/L) <0.010 METHYL TRI- THION, TOTAL (UG/L) ENDO- SULFAN, TOTAL (UG/L) <0.010 MI REX, TOTAL (UG/L) <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 <0.01 <0.01 DATE JUN 1991 21... PARA- THION, TOTAL (UQ/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) PER- THANB TOTAL (UG/L) TOX- APHENB, TOTAL (UG/L) TOTAL TRI- THION (UG/L) 2,4-D, TOTAL (UG/L) <0.01 2,4,5-T 2, 4-DP SILVBX, TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) <0.10 <1 <0.01 <0.01 <0.01 <0.01 <0.01 168 RIO PUERTO NDBVO BASIN 50049000 RIO PIEDRAS AT RIO PIEDRAS, PR LOCATION.--Lat 18®23'48', long 66«03'24", Hydrologic Unit 21010005, on left bank, at bridge on Highway 1, 0.3 mi (0.5 km) southwest of the plaza in Rio Piedras, and 0.4 mi (0.6 km) downstream from diversion for water supply. DRAINAGE AREA.--12.5 mi 1 (32.4 km»). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—October 1958 (maximum discharge Measurement only), 1959-64 (annual low-flow measurements only), July 1971 to September 1982, October 1987 to current year. GAGE.—Water-stage recorder and crest-stage gage. Elevation of gage is 50 ft (15 m), from topographic map. RBMARKS.—Records fair except those for estimated daily discharges, which are poor. Low flow affected by diversions for water supply. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--15 years (1972-82,1988-91), 29.3 ft'/s (0.830 mVs), 31.83 in/yr (808 mm/yr), 21,230 acre-ft/yr (26.2 hmVyr)/ median of yearly mean discharges, 27 ftVs (0.76 mVs), 19,600 acre-ft/yr (24 hmVyr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge 10,000 ftVs (283 mVs), Dec. 11, 1975, gage height, 21.02 ft (6.407 m), from rating curve extended above 3,000 ft*/s (85.0 mVs) on basis of slope-area measurements; minimum daily discharge, 0.26 ftVs (0.007 mj/s), May 19, 1977. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 2,800 ftVs (79.3 mVs) and maximum (*)i Discharge (ftVs) (mVs) Gage height (ft) (m) Date Time (ftVs) (mVs) (ft) (m) Date Oct. 17 unknown *5,090 144 *11.99 3.654 Feb. 18 Minimum discharge, 4.7 ftVs (0.133 •?/•), Aug. 14, 15, Sept. 23, 24. Time 2145 Discharge (ftVs) (mVs) 4,570 129 Gage height (ft) (m) 11.34 3.456 DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUQ 1 25 2 11 3 134 4 70 5 31 6 32 7 103 8 35 9 151 10 252 11 164 12 26 13 18 14 17 15 15 16 25 17 e791 18 e297 19 73 20 47 21 335 22 39 23 24 24 83 25 146 26 94 27 26 28 20 29 19 30 23 31 17 TOTAL 3143 MEAN 101 MAX 791 MIN 11 AC-FT 6230 CFSM 8.11 IN. 9.35 CAL YR 1990 WTR YR 1991 17 16 17 15 21 14 16 15 15 14 13 13 12 13 14 14 15 13 13 20 20 15 12 12 12 41 34 18 53 48 —— 565 18.8 53 12 1120 1.51 1.68 TOTAL 10960. TOTAL 11172. 81 50 118 27 16 14 14 13 13 13 22 17 15 16 15 25 14 15 13 13 13 14 21 19 11 11 15 82 151 55 167 1083 34.9 167 11 2150 2.79 3.22 8 MEAN 1 MEAN 78 30 22 35 29 21 25 15 23 27 19 33 13 12 13 13 12 11 11 11 11 10 11 11 11 11 11 12 12 12 27 592 19.1 78 10 1170 1.53 1.76 30.0 MAX 30.6 MAX 14 14 17 12 179 31 17 12 12 15 25 15 13 11 11 11 11 403 149 170 34 22 12 11 11 10 10 10 —— 1262 45.1 403 10 2500 3.61 3.76 791 MIN 791 MIN 14 12 11 11 12 13 12 12 12 12 13 12 12 11 12 12 12 20 11 9.8 11 145 12 10 22 16 10 9.8 9.7 9.3 9.1 509.7 16.4 145 9.1 1010 1.32 1.52 9.0 27 8.4 8.1 13 9.6 9.7 61 12 14 15 50 39 15 108 32 16 17 14 14 13 12 12 11 36 12 11 10 10 10 —— 628.8 21.0 108 8.1 1250 1.68 1.87 6.6 AC-FT 21740 5.2 AC-FT 22160 10 10 12 167 46 18 24 16 18 29 12 17 9.6 8.7 8.9 10 9.4 38 14 90 16 14 11 10 15 17 11 8.8 8.6 8.8 8.1 695.9 22.4 167 8.1 1380 1.80 2.07 CFSM 2 CFSM 2 8.2 7.9 7.8 8.4 10 9.4 8.0 8.0 7.9 8.2 8.4 9.3 7.9 9.4 7.9 7.8 8.6 30 26 68 62 15 11 9.1 7.7 7.5 10 7.1 7.2 14 —— 417.7 13.9 68 7.1 829 1.11 1.24 .40 IN. .45 IN. 7.5 6.6 18 8.1 7.3 7.2 7.6 11 7.2 6.4 6.5 6.7 7.0 7.7 115 149 15 11 11 12 11 13 13 17 15 15 17 185 28 21 12 774.8 25.0 185 6.4 1540 2.00 2.31 32.62 33.25 9.4 11 9.9 28 17 9.5 9.9 6.6 6.4 6.0 5.8 6.9 5.3 5.8 7.8 138 271 12 7.9 96 134 32 14 8.7 8.9 7.7 157 28 12 8.9 9.7 1091.1 35.2 271 5.3 2160 2.82 3.25 15 8.9 7.1 6.6 6.6 6.5 53 24 6.6 10 7.1 7.8 7.6 6.8 6.1 9.8 15 8.5 7.9 26 6.8 21 5.7 5.2 12 6.5 36 11 29 29 —— 409.1 13.6 53 5.2 811 1.09 1.22 Estimated 169 RIO PDBRTO NOBVO BASIN 50049000 RIO PIBDRAS AT RIO PIBDRAS, PR--Continued HATER QUALITY RECORDS PERIOD OF RECORD.--OCTOBER 1989 TO CURRENT YEAR DATE TIME OCT. 05 0916 NOV. 16 1416 DEC. 26 1149 STRBAMFLOW, INSTANTANBODS (CFS) 33 12 14 SPECIFIC CON- TBMPERA- DUCTANCB TURK (DMHOS) (DBG C) DATE TIME 336 453 458 26.5 27.0 25.5 JAN. 24 1406 FEB. 14 0953 STRBAMFLOW, INSTANTANBODS (CFS) 16.1 17.7 SPECIFIC CON- TBMPBRA- DUCTANCB TORE (UMHOS) (DBG C) 400 446 28.0 27.5 170 RIO PUERTO NUBVO BASIN 50049000 RIO PIBDRAS AT RIO PIEDRAS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.— Water year* 1988 to current year. INSTRUMENTATION.— USD-77 and automatic sediment sampler. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGEt October 1988 to September 1991. EXTREMES FOR PERIOD OF DAILY RECORD.— SEDIMENT CONCENTRATIONt Maximum daily mean, 13,000 mff/L Sep. 18, 1989) Minimum daily mean, 4 rng/L June 4, 1990. SEDIMENT LOADSt Maximum daily mean, 165,000 ton* (150,200 tonnes) Sep. 18, 1989; Minimum daily mean, 0.09 ton (0.08 tonne) Sep. 24, 1991. EXTREMES FOR WATER YEARS 1991.— SEDIMENT CONCENTRATION t Maximum daily mean, 2,400 mff/L Aug. 21, 1991; Minimum daily mean, 6 m0/L several day*. SEDIMENT LOADSt Maximum daily mean, 7,730 ton* (7,010 tonne*) Oct.17, 1990; Minimum daily mean, 0.09 ton (0.08 tonne) Sep. 24, 1991. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CF8) (MG/L) (TONS/DAY) NOVEMBER MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CF8) .(MG/L) (TONS/DAY) DECEMBER 25 11 134 70 31 32 103 35 151 252 164 26 18 17 15 25 e791 e297 73 47 335 39 24 83 146 94 26 20 19 23 17 77 32 1670 343 106 105 521 105 1330 1430 520 67 36 34 30 76 el!70 e854 428 144 2260 98 53 549 996 530 41 18 15 56 33 19 .97 1520 136 11 20 262 12 2960 3360 508 5.6 1.7 1.5 1.2 16 e7730 e!300 131 130 4010 12 3.5 763 1270 421 3.1 .98 .77 6.5 1.6 17 16 17 15 21 14 16 15 15 14 13 13 12 13 14 14 15 13 13 20 20 15 12 12 12 41 34 18 53 48 31 30 30 30 57 19 12 12 12 12 12 12 11 11 11 11 11 11 11 45 49 30 22 21 21 163 118 46 247 207 1.4 1.3 1.4 1.2 5.7 .73 .50 .47 .49 .46 .41 .39 .36 .39 .40 .40 .46 .38 .38 5.1 5.3 1.3 .72 .67 .66 43 23 2.9 146 78 81 50 118 27 16 14 14 13 13 13 22 17 15 16 15 25 14 15 13 13 13 14 21 19 11 11 15 82 151 55 167 426 204 773 95 29 27 25 22 22 22 66 45 28 25 25 66 25 22 21 21 21 21 59 54 18 18 33 386 874 206 1050 263 74 935 7.8 1.3 1.0 .94 .76 .77 .78 13 2.4 1.1 1.1 1.1 8.7 .89 .90 .72 .71 .71 .80 5.4 5.9 .57 .56 1.7 169 957 49 778 TOTAL 3143 24618.42 565 323.87 1083 3284.61 e Estimated 171 RIO PUERTO NDBVO BASIN 50049000 RIO PIBDRAS AT RIO PIBDRAS, PR—Continued SBDIMBNT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) CONCEN- SBDIMBNT TRATION DISCHARGE (MO/L) (TONS/DAY) JANUARY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 78 30 22 35 29 21 25 15 23 27 19 33 13 12 13 13 12 11 11 11 11 10 11 11 11 11 11 12 12 12 27 352 59 54 132 74 58 74 29 47 89 43 147 28 22 27 20 20 20 20 20 20 20 18 13 10 10 10 10 10 10 68 126 5.1 4.6 32 9.1 3.5 6.5 1.1 3.4 12 5.0 32 1.0 .73 1.1 .72 .63 .56 .61 .59 .60 .53 .50 .37 .29 .28 .30 .31 .33 .32 8.3 14 14 17 12 179 31 17 12 12 15 25 15 13 11 11 11 11 403 149 170 34 22 12 11 11 10 10 10 FEBRUARY 21 13 12 11 291 101 41 21 20 39 71 39 28 21 20 20 21 205 678 1250 102 91 22 21 19 16 12 10 .81 .48 .56 .35 702 15 2.2 .66 .67 2.8 11 1.8 .98 .62 .60 .61 .65 785 557 1950 12 6.8 .71 .62 .57 .42 .33 .26 MEAN DISCHARGE (CFS) 14 12 11 11 12 13 12 12 12 12 13 12 12 11 12 12 12 20 11 9.8 11 145 12 10 22 16 10 9.8 9.7 9.3 9.1 MEAN CONCEN- SBDIMBNT TRATION DISCHARGE (MG/L) (TONS/DAY) MARCH 21 673 20 19 17 15 13 12 12 11 10 10 10 9 10 10 10 52 22 19 18 1050 29 16 78 42 28 14 14 14 13 1.4 25 .58 .54 .55 .51 .44 .39 .39 .35 .34 .32 .32 .27 .31 .33 .32 5.5 .70 .55 .53 1660 .96 .40 22 7.2 .80 .39 .37 .36 .32 TOTAL 592 258.37 1262 4055.50 509.7 1732.44 172 RIO PUERTO NOEVO BASIN 50049000 RIO PIBDRAS AT RIO PIBDRAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 AY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 * 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) 9.0 27 8.4 8.1 13 9.6 9.7 61 12 14 15 50 39 15 108 32 16 17 14 14 13 12 12 11 36 12 11 10 10 10 MEAN CONCBN- SEDIMENT TRATION DISCHARCB (MG/L) (TONS/DAY) APRIL 13 97 14 25 31 11 13 294 22 31 33 295 173 44 770 116 30 28 27 25 22 21 20 16 142 23 16 445 445 16 .32 29 .33 .55 2.3 .29 .33 138 .71 2.1 1.7 356 98 1.9 1270 19 1.3 1.3 1.0 .96 .76 .66 .66 .46 54 .74 .45 11 11 .43 MEAN DISCHARGE (CFS) 10 10 12 167 46 18 24 16 18 29 12 17 9.6 8.7 8.9 10 9.4 38 14 90 16 14 11 10 15 17 11 8.8 8.6 8.8 8.1 MEAN CONCBN- SBDIMBNT TRATION DISCHARGE (MG/L) (TONS/DAY) MEAN DISCHARGE (CPS) MAY 16 19 22 1070 269 108 80 23 51 106 26 51 15 14 12 13 18 153 32 586 120 30 18 16 33 41 19 14 12 11 11 .44 .51 .73 3030 103 6.1 18 .97 4.4 31 .92 7.9 .39 .32 .30 .34 .73 48 1.4 602 6.1 1.2 .55 .44 1.7 4.1 .54 .31 .27 .26 .24 MEAN CONCBN- SEDIMENT TRATION DISCHARCB (MG/L) (TONS/DAY) JUNE 8.2 7.9 7.8 8.4 10 9.4 8.0 8.0 7.9 8.2 8.4 9.3 7.9 9.4 7.9 7.8 8.6 30 26 68 62 15 11 9.1 7.7 7.5 10 7.1 7.2 14 11 11 10 10 11 9 8 9 10 10 16 10 11 12 12 12 12 113 137 511 283 31 15 13 10 10 19 12 9 30 .24 .22 .20 .22 .26 .23 .16 .19 .21 .21 .35 .24 .24 .29 .26 .24 .27 57 31 405 170 1.6 .44 .32 .21 .20 .76 .24 .18 1.9 TOTAL 628.8 2005.25 695.9 3873.16 417.7 672.88 173 RIO PUERTO NUEVO BASIN 50049000 RIO PIBDRAS AT RIO PIBDRAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SBPTBHBBR 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR MEAN DISCHARGE (CFS) 7.5 6.6 18 8.1 7.3 7.2 7.6 11 7.2 6.4 6.5 6.7 7.0 7.7 115 149 15 11 11 12 11 13 13 17 15 15 17 185 28 21 12 774.8 11172 . 1 MEAN CONCBN- SEDIMENT TRATION DISCHAROE (MG/L) (TONS/DAY) JULY MEAN MEAN CONCBN- SEDIMENT DISCHAROE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 13 10 54 14 10 10 10 21 11 8 9 9 10 11 1350 703 23 16 15 15 14 12 14 15 15 16 23 1810 72 44 17 —— .27 .17 11 .33 .19 .19 .19 1.2 .22 .15 .16 .16 .20 .28 2230 1060 1.0 .47 .46 .50 .40 .41 .48 .67 .59 .63 1.0 5430 7.1 3.9 .51 8752.83 60846.78 AUGUST 9.4 11 9.9 28 17 9.5 9.9 6.6 6.4 6.0 5.8 6.9 5.3 5.8 7.8 138 271 12 7.9 96 134 32 14 8.7 8.9 7.7 157 28 12 8.9 9.7 1091.1 15 23 19 106 51 44 21 8 7 7 6 6 6 8 15 517 516 23 12 722 2470 93 29 11 12 11 1150 84 21 14 19 .38 1.0 .54 38 5.0 1.2 .68 .15 .13 .12 .10 .12 .08 .19 .53 1270 1940 .88 .24 1130 4600 12 1.3 .27 .29 .23 1760 9.4 .67 .35 .60 10774.45 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SBPTBHBBR 15 8.9 7.1 6.6 6.6 6.5 53 24 6.6 10 7.1 7.8 7.6 6.8 6.1 9.8 15 8.5 7.9 26 6.8 21 5.7 5.2 12 6.5 36 11 29 29 13 12 10 9 10 12 246 82 10 21 9 11 9 7 7 25 38 11 10 114 10 72 7 7 21 10 193 18 90 85 .28 .30 .19 .15 .17 .22 229 21 .18 1.5 .18 .23 .19 .13 .12 1.1 3.5 .25 .21 58 .17 20 .11 .09 1.0 .18 129 .55 16 11 409.1 495.00 174 RIO PUERTO NUBVO BASIN 50049000 RIO PIBDRA8 AT RIO PIRDRAS, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 PARTICLB-SIZB DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1990 03... 09... 11... 17... 21... FBB 1991 05... 18... MAR 22... MAY 04... JUN 20... JUL 15... AUG 21... TIME 0530 1825 1500 1500 0010 1650 2030 0935 1340 1340 1850 1535 DIS- CHARGE, INST. CUBIC FEET PER SECOND 538 1040 1490 1880 1100 1706 1600 628 1107 482 962 443 SEDI- MENT, SUS- PENDED (MG/L) 6580 10100 5010 17600 7000 2216 475 11350 9840 3550 12200 22600 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 9560 28400 20200 89300 20800 10200 2050 19200 29400 4620 31700 27000 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 25 23 22 -- 26 -- 39 — 23 21 27 25 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 36 32 34— 35 — 58 — 36 35 39 37 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 50 45 45— 46 — 62 — 51 46 52 51 DATE OCT 1990 03... 09... 11... 17... 21... FBB 1991 05... 18... MAR 22... MAY 04... JUN 20... JUL 15... AUG 21... SED. SUSP. FALL DIAM. PERCENT FINER THAN 016 MM 62 59 57— 57 __ 68 — 63 56 66 66 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 74 70 69— 66 __ 69 — 76 69 79 74 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 94 88 86 84 88 99 96 82 93 90 95 98 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 99 96 94 94 94 100 97 98 97 97 98 99 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 100 99 99 98 99 100 98 99 99 99 99 100 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 100 100 100 100 100 100 99 99 100 100 100 100 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 100 100 100 100 99 99 100 100 100 100 175 RIO PUERTO NOEVO BASIN 50049000 RIO PIEDRAS AT RIO PIEDRAS, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1990 03... 09... 10... 10... 17... 17... 21... 21... PEB 1991 05... 05... 18... 18... MAY 04... 04... JUN 20... JUL 15... 16... AUQ 16... 16... 21... 21... TIME 0345 1735 1350 1620 1510 1550 0020 0200 1550 1720 1940 2200 1310 1530 1240 1810 1050 1325 1415 1455 1845 STREAM- FLOW, INSTAN- TANEOUS (CFS) 359 831 1230 483 2730 3980 1170 713 616 1170 329 340 547 681 474 362 893 314 306 366 225 SBDI- SUS- PBNDED (MG/L) 7600 14300 5100 2600 12400 4800 10700 2030 1100 1500 881 695 6870 5840 2990 2330 4110 4630 3140 3070 5480 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 7370 32100 17000 3390 91400 51600 33800 3910 1830 4740 782 638 10100 10700 3830 2280 9910 3930 2590 3030 3330 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 97 90. 75 89 83 79 88 85 99 100 99 100 84 92 78 91 86 88 78 64 87 176 RIO PUBRTO NUEVO BASIN 50049100 RIO PIEDRAS AT HATO RBY, PR LOCATION.—Lat 18°24'34", long 66°04'10", Hydrologic Unit 21010005, at bridge on Avenlda Plfielro at Bxpreso Las America!, and 0.8 mi (1.3 km) southwest of Hato Rey. DRAINAGE ARBA.--15.4 mi 1 (39.9 km*). MATER-DISCHARGE RECORDS PERIOD OF RECORD.—June 1970 to December 1987 (discharge Measurements only), 1972 to December 1982 (maximum discharge only), January 1988 to current year. QAQB.—Water-stage recorder and crest-stage gage. Blevatlon of gage Is 16 ft (5 m), from topographic Bap. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Mean daily discharge affected by sewage discharges (approximately 2.0 ft'/s (0.06 m'/s)), 20 ft (6 m) upstream from gaging station. EXTREMES FOR PERIOD OF RBCORD.--Maximum discharge 8,640 ft'/s (245 m'/s), June 17, 1970, gage height 20.77 ft (6.331 m), from floodmarks, from rating curve extended above 3,000 ft'/s (85.0 m'/s) on basis of slope-area and contracted opening measurements of peak flow; minimum daily discharge 8.4 ft*/s (0.238 m'/s), May 23, 1989. EXTREMES FOR WATER YEARS 1988-90.—Peak discharge greater than base discharge of 2,500 ft'/s (70.8 m'/s) and maximum* (*)i Discharge Gage height Discharge Gage height Date Time (ft'/s) (m'/s) (ft) (m) Date Time (ft'/s) (m'/s) (ft) (m) Oct. 17 1615 4,390 124 15.99 4.874 Feb. 18 2200 *5,560 157 *17.42 5.310 Minimum daily discharge, 8.8 ft'/s (0.249 m'/s), Aug. 11. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT MOV DEC JAN FBB MAR APR MAY JUM JDL ADO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTY YR 30 13 257 108 40 81 173 44 255 325 309 37 24 21 18 51 463 441 140 66 487 61 33 114 230 166 45 34 27 31 21 4145 134 487 13 8220 8.80 10.14 1990 TOTAL 1991 TOTAL 19 16 16 15 24 14 20 14 15 14 13 12 13 13 13 14 13 12 14 40 30 14 13 13 14 62 49 20 95 84 —— 718 23.9 95 12 1420 1.57 1.76 16251.3 17086.7 122 81 196 41 23 18 15 16 15 15 23 19 17 19 17 32 15 17 17 18 21 20 40 33 17 17 27 154 279 90 291 1725 55.6 291 15 3420 3.66 4.22 MEAN MEAN 187 66 37 76 65 46 43 22 32 38 25 55 22 20 21 18 17 16 14 16 16 15 17 15 16 16 16 15 15 16 41 1034 33.4 187 14 2050 2.19 2.53 44.5 MAX 46.8 MAX 20 19 23 14 232 51 37 22 22 33 41 22 21 18 16 15 14 679 310 338 79 50 34 30 27 25 26 27 —— 2245 80.2 679 14 4450 5.27 5.49 487 MIN 679 MIN 33 23 23 22 24 24 23 24 20 20 23 19 19 18 18 18 17 36 17 15 16 175 17 13 54 19 16 12 12 12 12 794 25.6 175 12 1570 1.69 1.94 9.5 AC-FT 8.8 AC-FT 13 28 23 11 14 10 12 76 16 21 21 71 58 14 248 46 20 19 17 16 15 15 14 15 61 18 15 13 14 14 —— 948 31.6 248 10 1880 2.08 2.32 32230 33890 14 15 17 197 90 28 41 27 25 40 20 42 17 14 15 15 17 73 26 141 23 17 14 12 18 19 12 9.8 9.5 9.6 9.2 1027 . 1 33.1 197 9.2 2040 2.18 2.51 CFSM 2.93 CFSM 3.08 9.5 9.6 9.1 9.4 13 10 10 10 11 10 10 12 11 13 11 12 12 39 57 139 120 25 18 15 12 11 15 11 11 35 —— 690.6 23.0 139 9.1 1370 1.51 1.69 IN. 39. IN. 41. 14 12 29 16 13 13 13 16 14 12 11 11 12 12 169 276 25 16 14 13 12 14 12 17 12 12 15 214 29 21 16 1085 35.0 276 11 2150 2.30 2.66 77 82 11 12 11 40 19 12 13 12 9.3 9.9 8.8 11 11 11 13 e250 e350 e24 e!2 142 156 55 28 18 23 15 324 47 18 15 16 1697.0 54.7 350 8.8 3370 3.60 4.15 23 13 11 11 11 14 97 68 18 31 15 16 15 13 13 20 26 14 13 90 17 47 15 14 49 12 154 22 54 62 —— 978 32.6 154 11 1940 2.14 2.39 Estimated 177 RIO PUERTO NOBVO BASIN 50049100 RIO PIBDRAS AT BATO RBY, PR WATER-QUALITY RECORDS LOCATION.--Lat li«24'34", long 66«04'10", at bridge on Avenida Pifiiero at Bxpreio La> Aaerieai, and 0. (1.3 km) •outhwett of Bato Rey. DRAIMAOB ARBA.—15.4 mi1 (39.9 km2 ) . PERIOD OF RECORD.—Water yean 1971 to current y*ar. WATER-QUALITY DATA, MATER YBAR OCTOBER 1990 TO SBPTBMBBR 1991 8 Mi DATB OCT 1990 30... DBG 18... FEB 1991 15... APR 18... JUN 25... AUO 02... THIS 1150 1335 1100 1135 1350 1435 DIS- CHARGE, INST. CUBIC PBBT PER SECOND 25 19 15 18 12 10 SPE- CIFIC CON- DUCT- ANCE (US/CM) 481 470 446 470 516 430 PB (STAND- ARD UNITS) 7.8 7.8 7.8 7.9 8.0 8.5 TEMPER- ATURE WATER (DBG C) 28.5 27.0 26.5 26.0 33.5 32.0 TUR- BID- ITY (NTU) 2.5 4.0 3.5 6.0 5.6 2.5 OXYGEN, DIS- SOLVED (MO/L) 5.7 5.4 5.9 6.1 4.1 8.3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 73 66 73 74 56 100 OXYGEN DEMAND, CHEM- ICAL (BIGB LEVEL) (MG/L) 22 27 23 28 21 12 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K170000 550000 K71000 200000 770000 K2000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K1700 53000 K18000 8100 35000 3900 DATB OCT 1990 30... DEC 18... FEB 1991 15... APR 18... JUN 25... AUQ 02... BARD- BARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MQ/L TOT FLD SOLVED AS CACO3) CACO3 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MQ/L (MG/L AS CA) AS MG) AS NA) 160 0 45 12 27 170 0 47 12 32 160 2 45 12 29 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT PET SULFIDB SOLVED FIELD TOTAL (MG/L MQ/L AS (MG/L AS K) 0.9 3.7 3.9 3.9 CACO3 160 164 170 170 170 160 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MQ/L <0.5 24 <0.5 18 18 (MG/L AS S) AS 804) AS CL) 32 40 35 SOLIDS, RESIDUE DATB OCT 1990 30... DBC 18... FEB 1991 15... APR 18... JUN 25... AUG 02... FLUO- RIDB, DIS- SOLVED (MQ/L AS F) 0.30 — — <0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI02) 28 — — 30 — 26 SUM OF CONSTI- TUENTS, DIS- SOLVED (MQ/L) 268 -- -- 285 — 265 SOLIDS, DIS- SOLVED (TONS PER DAY) 17.7 — — 13.5 — 7.23 TOTAL AT 105 DBG. C, SUS- PENDED (MQ/L) <1 <1 5 10 <1 <1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.610 0.570 0.540 0.960 0.530 0.560 NITRO- GEN, NITRITE TOTAL (MQ/L AS N) 0.190 0.230 0.260 0.140 0.270 0.090 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.800 0.800 0.800 1.10 0.800 0.650 NITRO- GEN, AMMONIA TOTAL (MQ/L AS N) 1.50 1.30 1.40 0.570 1.30 0.250 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.40 0.70 0.70 0.53 0.70 0.45 non-ideal count 178 RIO PUERTO NUEVO BASIN 50049100 RIO PIEDRAS AT HATO RBY, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 30... DEC 18... FEB 1991 15... APR 18... JON 25... ADO 02... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MQ/L AS N) NITRO- GEN, TOTAL (MG/L AS N03) PHOS- PHORUS TOTAL (MQ/L AS P) ARSENIC TOTAL (UQ/L AS AS) BARIUM, TOTAL RECOV- ERABLE (UQ/L AS BA) BORON, TOTAL RECOV- ERABLE (UG/L AS B) CADMIUM TOTAL RECOV- ERABLE (UQ/L AS CD) CHRO- MIUM, TOTAL RECOV- ERABLE (UQ/L AS CR) COPPER, TOTAL RECOV- ERABLE (UQ/L AS CU) 1.9 2.0 2.1 1.1 2.0 0.70 2.7 2.8 2.9 2.2 2.8 1.3 12 15 13 9.7 12 6.0 0.400 0.530 0.450 0.250 0.510 0.260 <1 200 <100 50 40 <1 <1 <1 10 10 DATE OCT 1990 30... DEC 18... FEB 1991 15... APR 18... JUN 25... AUQ 02... IRON, TOTAL RECOV- ERABLE (UQ/L AS FE) (01045) LEAD, TOTAL RECOV- ERABLE (UQ/L AS PB) (01051) MANGA- NESE, TOTAL RECOV- ERABLE (UQ/L AS UN) (01055) MERCURY TOTAL RECOV- ERABLE (UQ/L AS HQ) (71900) SELE- NIUM, TOTAL (UQ/L AS SB) (01147) SILVER, TOTAL RECOV- ERABLE (UG/L AS AQ) (01077) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) (01092) CYANIDE TOTAL (MG/L AS CN) (00720) PHENOLS TOTAL (UQ/L) (32730) MBTHY- LBNB BLUE ACTIVE SUB- STANCE (MQ/L) (38260) 480 640 110 160 <0.10 <0.10 <1 <1 <1 <0.010 <0.010 0.20 0.07 RIO PUERTO MDEVO BASIN 1 7 9 50049310 QOBBRADA JOSEFIHA AT PINERO AVEHOB, PR LOCATION.—Lat lt«24'34", long CC«04'31 <> Hydrologie Unit 21010005, cm right bank, 75 ft (23 m) downstream from bridge at highway 17, Pifiero Avenue, l.C mi (2.C km), northwest from Rio Piedras Plaza, 0.8 mi (1.3 km) north from University of Puerto Rico medical Center and 0.4 mi (O.C km) upstream from confluence with Rio Piedras. DRAINAGE AREA.--19.0 mi• (49.2km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—February 1988 to November 1990 (discontinued). GAGE.—Mater-stage recorder. Elevation of gage is 13.1 ft (4.0 m), from topographic map. REMARKS.—Record poor. EXTREMES FOR PERIOD OF RBCORD.--Maximum discharge, 4,320 ftVs (122 •?/•), Sept. 18, 1989, gage-height 8.69 ft (2.C49 m) from rating curve extended above 100 fts/s (2.83 •?/•) on basis of step-backwater analysis; minimum discharge, 0.82 ftVs (0.023 mVs), May 27, 1989. EXTREMES FOR CURRENT PERIOD.—Peak discharges greater than base discharge of 1,800 ft'/s (51.0 •?/•) and maximum (*): Discharge Gage height Discharge Gag* height Date Time (ftVs) (mVs) (ft) (m) Date Time (ftVs) (•?/•) (ft) (m) Oct. 11 0500 *2,240 C3.4 *C.40 1.951 No other peak greater than base discharge. Minimum daily discharge, 0.8C ftVs (0.024 mVs), Oct. 2. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY OUN JUL AUG SEP 1 2 3 4 5 C 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 2t 29 30 31 TOTAL MEAN MAX MIN AC-FT CF8M IN. 1.2 .8C 42 8.0 1.5 20 18 1.9 63 11 73 1.4 1.8 1.8 1.3 19 42 C7 4.9 6.9 32 1.7 3.0 15 25 C.6 1.9 2.4 1.5 1.7 1.3 478. CC 15.4 73 .86 949 4.02 4.64 1.2 .9C .90 1.9 2.2 l.C 4.3 2.2 2.4 2.5 2.2 1.6 2.1 1.7 2.4 3.4 3.5 l.C 1.5 19 5.5 3.7 1.2 1.2 1.0 15 180 RIO PUERTO NUBVO BASIN 50049310 QUBBRADA JOSEFINA AT PINBRO AVBNUB, PR—Continued HATBR QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1989 TO CURRENT YEAR DATE TIME OCT. 05 1139 STRBAMFLOW, INSTANTANEOUS (CFS) 1.32 SPECIFIC CON- DUCTANCE (UMHOS) 439 TEMPERA- TURE (DBG C) 33.5 STRBAMFLOW, SPECIFIC CON- DATE TIME INSTANTANEOUS DUCTANCE (CFS) NOV. 09 1438 2.48 (UMHOS) 402 TEMPERA- TURE (DBG C) 23.5 181 RIO PUERTO NDEVO BASIN 50049820 LACUNA SAN JOSE NO. 2 AT SAN JUAN, PR WATER-QUALITY RECORDS LOCATION.--Lat 18«25'46", long 66°02'10*, 0.2 mi (0.3 In) eaat of Cafio de Martin Pefia, and 650 ft (200 a) •outh of I«la Guachinango. DRAINAGE AREA.—Indeterminate. PERIOD OF RECORD.--Water year* 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 13... JAN 1991 04... MAR 01... MAY 06... JUN 26... AUG 26... DATE NOV 1990 13... JAN 1991 04... MAR 01... MAY 06... JUN 26... AUG 26... TIME 0930 0910 1030 1145 0930 0930 ALKA- LINITY WAT WH TOT FBT FIELD MQ/L AS CAC03 110 81 92 100 130 90 SPE- CIFIC CON- DUCT- ANCE (US/CM) 22400 18000 17700 22500 27000 29000 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MQ/L) 16 19 52 43 27 17 PH (STAND- ARD UNITS) 7.2 8.9 8.4 8.0 8.3 7.5 NITRO- GEN, NITRITE TOTAL (MQ/L AS N) 0.020 0.010 0.010 0.040 0.040 0.010 TEMPER- ATURE WATER (DBG C) 28.0 24.0 26.5 29.5 28.5 30.0 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) <0.100 <0.100 <0.050 <0.050 <0.050 <0.050 TRANS- PAR- ENCY (SBCCHI DISK) (IN) 28.0 15.0 16.0 — 1.30 — — NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 2.10 0.050 0.040 2.30 0.580 0.630 OXYGEN, DIS- SOLVED (MQ/L) 0.6 9.3 6.1 6.0 5.5 1.0 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.0 0.75 2.5 4.6 1.8 0.87 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) — 108 74 76 -- 13 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.7 0.80 2.5 6.9 2.4 1.5 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 94000 9000 690 4200 6000 3500 PHOS- PHORUS TOTAL (MG/L AS P) 0.410 0.100 0.410 0.810 0.830 0.440 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 9300 200 220 560 450 380 CARBON, ORGANIC TOTAL (MG/L AS C) 7.5 8.3 17 16 12 7.3 182 RIO PUERTO NDBVO BASIN 50049920 BAHIA US SAN JUAN NO. 5 AT SAN JUAN, PR WATER-QUALITY RECORDS LOCATION—Lat 18°26'37", long 66°05'11", 0.4 ml (0.6 km) w»«t of Puente de la Conatitucion, and O.S mi (0.8 km) south from U.S. Naval Reservation. DRAINAGE—Indeterminate. PERIOD OF RECORD--Water years 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 13 JAN 04 MAR 01 MAY 07 JUN 26 AUQ 26 1990 . . . 1991 . . . . . . . . . NOV 13 JAN 04 MAR 01 MAY 07 JUN 26 AUG 26 K OXYGEN, COLI- ALKA- RESIDUE SPE- TRANS- DIS- FORM, STREP- LINITY TOTAL CIFIC PAR- SOLVED FECAL, TOCOCCI WAT WH AT 105 CON- PH TEMPER- BNCY OXYGEN, (PER- 0.45 FECAL, TOT PET DBG. C, DUCT- (STAND- ATURB (SECCHI DIS- CENT UM-MF (COLS. FIELD SOS- TIME ANCE ARD WATER DISK) SOLVED SATUR- (COLS./ PER MG/L AS FENDED (US/CM) UNITS) (DBG C) (IN) (MG/L) ATION) 100 ML) 100 ML) CACO3 (MG/L) 1130 41000 1015 49000 1230 50000 0935 1040 45000 1030 44600 NITRO- NITRO- GEN, GEN, NITRATE NITRITE TOTAL TOTAL DATE (MG/L (MG/L AS N) AS N) 1990 0.150 0.050 1991 0.170 0.030 0.130 0.100 0.080 0.050 0.030 0.048 0.020 - non- ideal count 8.0 29 7.7 25 7.6 26 — 8.0 29 8.0 29 NITRO- GEN, .0 26. .5 20. .0 26. — .0 1. .0 NITRO- GEN, NO2+NO3 AMMONIA TOTAL (MG/L AS N) 0.200 0.200 0.230 0.130 <0.050 0.068 TOTAL (MG/L AS N) 0.680 0.450 1.30 0.520 0.670 0.160 0 0 0 _ 10 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.22 0.35 1.2 0.68 0.73 0.24 7.8 7.3 5.9 _ 2.8 4.1 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.90 0.80 2.5 1.2 1.4 0.40 99 59000 K1200 87 89000 5600 71 600 20 ______ 5500 2200 52 2700 K730 NITRO- NITRO- PBOS- GBN, GEN, PHORUS TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L AS N) AS N03) AS P) 1.1 4.9 0.260 1.0 4.4 0.090 2.7 12 0.310 1.3 5.9 0.180 0.230 0.47 2.1 0.130 160 88 160 - 140 120 CARBON, ORGANIC TOTAL (MG/L AS C) 6.0 4.4 7.1 4.3 4.1 3.1 44 52 25 70 50 57 EXPLANATION SURFACE-WATER STATION 0509 AND NUMBER w 0554 QUALITY-OF-WATER STATION T AND NUMBER ry n™ QUALITY-OF-WATER V 0&7& PARTIAL RECORD STATION AND NUMBER 222 rn ES Figure 19.-Rfo Grande de Lofza basin. WELL AND WELL NUMBER 0590 LAKE-ELEVATION STATION 184 RIO GRANDS DB LOIZA BASIN 50050300 QUEBRADA BLASINA NEAR CAROLINA, PR WATER-QUALITY RECORDS LOCATION.—Lat 18*23'27•, long 65°58'28-, at bridge on Highway 3, 1.4 ml (2.3 km) south of Valle Arrlba Height* housing area, and 1.2 ml (1.9 km) west-southwest of Carolina plaza. DRAINAGE AREA.--2.96 ml3 (7.67 km2). PERIOD OF RECORD.—Water years 1973 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 07... DEC 18... FBB 1991 07... APR 05... JUN 06... AUG 26... DATE NOV 1990 07... DEC 18... FEB 1991 07... APR 05... JUN 06... AUG 26... TIME 1140 1150 1055 1030 1305 1035 AS DIS- CHARGE, INST. CUBIC FEET PER SPE- CIFIC CON- DUCT- ANCE SECOND (US/CM) 16 15 6.2 9.5 6.7 8.6 673 422 437 419 520 456 HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED MG/L AS (MG/L PH (STAND- ARD UNITS) 8.0 7.7 7.6 7.8 7.9 7.9 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) TEMPER- ATURE WATER (DBG C) 25.5 24.5 23.0 25.5 27.5 27.5 SODIUM, DIS- SOLVED (MG/L AS NA) TUR- BID- ITY (NTU) 3400 87 3.1 3.1 43 30 SODIUM AD- SORP- TION RATIO CACO3) CAC03 AS CA) 220 2 74 8.6 23 140 0 42 9.5 28 180 1 56 9.1 29 OXYGEN, DIS- SOLVED (MG/L) 5.6 5.5 5.9 6.4 5.6 5.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 68 65 68 77 70 68 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 590 47 34 33 26 38 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K100000 120000 K110000 K600000 38000 4700 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 58000 23000 72000 30000 2700 5900 ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATE RIDE, DIS- TOT FBT SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED AS K) 0.7 3.9 1 2.7 0.9 5.0 (MG/L MG/L AS (MG/L CAC03 172 170 160 200 180 (MG/L <0.5 45 <0.5 16 16 (MG/L AS S) AS S04) AS CL) 34 28 37 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DATE NOV 1990 07... DEC 18... FBB 1991 07... APR 05... JUN 06... AUG 26... K = non-lde RIDE, DIS- SOLVED (MQ/L AS F) <0.10 — — 0.50 — 0.20 al count DIS- SOLVED (MG/L AS 8102) 7.9 — — 27 — 22 CONSTI- TUENTS, DIS- SOLVED (MG/L) 310 — -_ 250 — 282 DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS SOS- TOTAL TOTAL TOTAL TOTAL TOTAL PER FENDED (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 5280 8 12 111 70 62 0.760 0.990 1.02 0.460 0.840 0.660 0.140 0.110 0.080 0.070 0.130 0.120 0.900 1.10 1.10 0.530 0.970 0.780 1.30 0.260 1.20 0.340 0.340 0.290 13 1.0 1.0 1.6 1.9 1.0 185 RIO GRANDE DB LOIZA BASIN 50050300 QUBBRADA BIASING NEAR CAROLINA, PR—Continued MATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 07... DEC 18... PBB 1991 07... APR OS... JUN 06... AUQ 26... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 14 1.3 2.2 1.9 2.2 1.3 NITRO- GEN, TOTAL (MG/L AS N) IS 2.4 3.3 2.4 3.2 2.1 NITRO- GEN, TOTAL (MG/L AS NO3) 66 11 IS 11 14 9.2 PHOS- PHORUS TOTAL (MG/L AS P) 0.540 0.280 0.360 1.00 0.810 0.630 ARSENIC TOTAL (UQ/L AS AS) <1 -- -- 2 -- — BARIUM, TOTAL RECOV- ERABLE (UQ/L AS BA) 1500 -- — <100 -- — BORON, CADMIUM TOTAL TOTAL RBCOV- RECOV- ERABLE ERABLE (UQ/L (UQ/L AS B) AS CD) 110 <1 __ __ 30 <1 __ __ CHRO- MIUM, TOTAL RECOV- ERABLE (UQ/L AS CR) 390 -- -- 17 -- -- COPPER, TOTAL RECOV- ERABLE (UQ/L AS CD) 360 — — 10 — — DATE NOV 1990 07... DEC 18... PBB 1991 07... APR 05... •TON 06... AUQ 26... IRON, TOTAL RECOV- ERABLE (UQ/L AS PB) LEAD, TOTAL RECOV- ERABLE (UQ/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UQ/L AS MN) MERCURY TOTAL RECOV- ERABLE (UQ/L AS HQ) SELE- NIUM, TOTAL (UQ/L AS SB) SILVER, TOTAL RECOV- ERABLE (UQ/L AS AQ) ZINC, TOTAL RECOV- ERABLE (UQ/L AS ZN) CYANIDE TOTAL (MQ/L AS CN) PHENOLS TOTAL (UQ/L) METHY- LBNB BLUB ACTIVE SUB- STANCE (MQ/L) 140000 2300 10000 1200 0.70 •cO.10 <2 <1 410 0.010 13 20 <0.010 0.15 0.04 P- ^ M PI ^ W p- W W M «^ PI O W to pOJP>P>P> p>tOtOtOl MWP-p-p. tO^dPlH P-tOP-W* PIOOltOP-1 H HdHH H PI M H H H to d ^ PI d H H O PI ^ to O d PI . .H .to d« O H d tO W . . ^ PI H M M O W M d O to OI p" M if * PI PI d P-M r» t t t to to to to to to d OOdd M 01 • PI d • P- M P- ...___ . .,__..._ W • tOM • . IHHCC CHdHHC W Ol HH Odd P- P- OI o o o d W M P- O H O O M d PI H O P- PI d OH OI HtO ^ OI OI OI W W p. OI ^ H W W W OI H W d PI OI M d O W W P> p> OI OI P- tO PI d PI P^ to to to W H PI p> p> to W O O OI W H H ^ H • • H d PI M M OI to OI OI PI P; to to to to P^ to « p^ to P- H d OI I M OI P- OI d I OI O d P- O P" ^ . > H .PI H M O OI PI M H > • P- H H PI PI PI M JM to M Md M 3 ^ ^ ^ to M M M d O W M MM M ^ i ^ OI M d i W 10 10 10 d O p- H ^ M M to to to O Md HOI M M O d P-PI P- d H M O O M to «O OI ..... ..H.OlH^ *«BP-tOtOtO HPId^P- • • H OH d d PI M M O O O OI to to W O OI • to to to to to toMp^top? OIP^I O d H p. ^ ^ p. PI o p" W tO to M M M M M M M M H « to M I ..... I M M^ ^ ^ I P-OIHM^MP- M^ • d H • p. O H 01 OI 00 . ^PI . . U) u) W to H H H H BE MHM HHH M M HOI d OI OI OI OI OI P- dd H H «• «• «• 01 «• tO d P-^ p" PI OI p" p. OP-PlHdd OI d H H M OI M it < ...... .'d*dtOOI p-to to to to to ^o to to . * H H H H O M «• PI H to «• to WWW ^d PI I I H H H I I I I . M IHHHH O O to « PI IHHHH HHHOd a a a 888 O M to H ^ tO d M W M H d tO PI OtO M H M M OI P- PI H H OlddP- W 01 PI d P- ^ ^ PI M W O O O O ^ M * p> H O PI ^ M OI H * > H H PI PI W « d Wd PI ^ • > PI . p. to O OI M OI OI . . « H dPI P- O « p. O p. to . . O . p. H to OI OI H OI H . . W H H PIPI O P> OI PI O ^ O H * p> H H OI ^ p" PI ^ « « d H PI ^ PI OI«O H O M O d > H H H .^ PI ^ PI to d > d P- ^ H ^ 33 O H OI OI OI OI H H HdPI^M to p-W OI O 187 RIO ORANDB DB LOIZA BASIN 50050900 RIO ORANDB DB LOIZA AT QUBBRADA ARENAS, PR—Continued WATER QUALITY RECORDS PERIOD OF RECORD.—WATER YEARS AUGUST 1981 TO CURRENT YEAR STRBAHFLOW, SPECIFIC CON- TEMPERA- STRBAMFLOW, SPECIFIC CON- TBHPBRA- DATB TIME INSTANTANEOUS DUCTANCE TURB DATB TIME INSTANTANEOUS DUCTANCB TURB (CFS) (UMHOS) (DBQ C) (CFS) (UMHOS) (DBQ C) FEB. 15 1304 14.4 152 23.0 JUL. 17 1527 14.2 140 28.5 MAR. 19 8.52 160 24.0 AUG. 14 1200 5.91 160 26.0 MAY 15 1050 9.58 145 24.5 SEP. 12 1240 8.91 150 27.0 JUN. 18 1057 6.33 165 25.0 188 RIO QRANDB DB LOIZA BASIN 50051150 QUBBRADA BLANCA AT BL JAGUAL, PR LOCATION.—Lat 18°09'40-, long 65°58'58-, Hydrologic Unit 21010005, 0.1 mi (0.2 km) upstream from bridge on Highway 181, and 2.8 mi (4.5 km) southwest of San Lorenzo. DRAINAGB ARBA.--3.25 mi* (8.42 km*). NATBR-DISCHARGB RBCORD8 PBRIOD OF RBCORD.—October 1984 to current year. GAGB.—Water-stage recorder. Elevation of gage is 459 ft (140 m), from topographic map. REMARKS.--Records fair. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--? years (1985-91), 7.72 ftVs (0.219 mVs), 32.26 in/yr (819 mm/yr), 5,590 acre-ft/yr (6.89 hmVyr). EXTREMES FOR PBRIOD OF RBCORD.--Maximum discharge, 7,400 ft'/s (210 mVs), may 17, 1985, gage height, 14.58 ft (4.444 m), from floodmark, from rating curve extended above 400 ft*/s (11.3 mVs) on basis of step-backwater analysis and slope-area measurement; minimum daily discharge, 0.38 ft*/s (0.011 mVs), Aug. 10, 1991. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 1,000 ftVs (28.3 m'/«) and maximum (*)t Discharge (ft'/s) (mVs) Gage height (ft) (m) Date Time Oct. 20 2245 *1,360 38.5 *8.51 2.594 Minimum daily discharge, 0.38 ftVs (0.011 mVs), Aug. 10. Date Time Discharge (ft'/s) (mVs) Gage height (ft) (m) No other peak greater than base discharge. DISCHARGE, CUBIC FEET PBR SECOND, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY J0N JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR .74 .92 1.1 .94 1.1 .74 .57 .80 1.4 5.9 2.2 1.5 6.7 4.6 3.6 18 15 28 29 57 49 22 11 20 43 50 38 23 14 10 8.0 467.81 15.1 57 .57 928 4.64 5.35 1990 1991 6.1 5.2 4.5 26 26 18 12 10 7.6 6.3 5.8 5.3 5.0 4.1 3.4 5.7 3.9 3.3 2.8 2.4 3.1 3.3 2.5 2.1 2.0 2.5 5.9 9.2 5.1 16 - — 215.1 7.17 26 2.0 427 2.21 2.46 TOTAL 1525 TOTAL 1895 6.8 7.9 19 11 5.3 3.7 3.0 2.7 2.5 2.3 2.0 1.9 1.9 13 6.2 3;7 2.7 2.3 2.0 1.9 1.9 1.7 1.8 1.8 1.6 1.4 1.4 1.4 2.7 3.7 47 168.2 5.43 47 1.4 334 1.67 1.93 .18 MEAN .78 MEAN 16 7.9 5.5 4.2 11 8.9 8.2 8.9 7.7 7.8 6.3 5.4 4.8 4.3 4.4 4.0 3.5 3.2 2.9 2.7 2.5 2.3 2.3 2.0 2.6 2.4 2.2 1.9 1.9 1.9 2.8 152.4 4.92 16 1.9 302 1.51 1.74 4.18 MAX 5.19 MAX 2.6 2.3 2.5 2.3 8.6 5.0 2.7 2.0 1.6 2.3 6.3 17 15 5.4 3.7 2.4 2.0 1.8 3.3 2.2 2.0 1.7 1.5 1.6 1.6 1.4 1.2 2.4 —— 104.4 3.73 17 1.2 207 1.15 1.19 53 MIN 74 MIN 1.9 1.5 1.8 1.8 1.7 7.5 8.6 15 5.8 3.4 2.8 2.2 1.9 1.8 1.6 1.3 1.2 1.5 1.7 1.1 1.3 2.5 1.9 1.3 1.0 .92 1.2 .87 .75 .72 .74 79.30 2.56 15 .72 157 .79 .91 .47 AC-FT .38 AC-FT .70 .71 .71 .67 .72 .77 .70 2.8 1.4 1.5 1.1 1.2 .93 .79 1.2 1.3 .87 1.3 1.1 .80 .73 .73 .65 .64 .59 .56 .54 .50 .46 .42 —— 27.09 .90 2.8 .42 54 .28 .31 3030 3760 .42 .42 .52 .46 .43 .45 .52 .72 .99 .80 3.5 4.5 1.4 .77 .61 .61 .68 2.9 1.3 .76 4.7 6.7 1.5 .86 9.2 3.2 1.3 .82 .63 .57 .53 52.77 1.70 9.2 .42 105 .52 .60 CFSM 1.29 CFSM 1.60 1.3 .92 .66 .57 1.8 1.8 1.9 1.1 .79 .66 .90 2.8 1.4 .81 .65 .54 .48 .69 .57 .52 2.4 1.2 .87 .88 .76 .56 .94 .70 .89 42—— 72.06 2.40 42 .48 143 .74 .82 IN. 17 IN. 21 74 24 6.5 4.5 2.8 2.0 1.4 1.2 1.2 1.1 .90 .84 .78 .72 16 52 14 4.6 2.6 2.3 1.3 .91 .71 1.6 1.0 .61 .58 .59 .52 5.2 1.4 227.86 7.35 74 .52 452 2.26 2.61 .46 .70 .66 .52 .50 .44 .42 .67 .53 .44 .41 .38 .39 .39 .41 .59 .80 .75 1.0 1.4 .92 .74 .93 13 3.6 2.0 1.2 .89 29 16 4.6 2.6 2.1 88.28 2.85 29 .38 175 .88 1.01 2.1 1.8 1.3 1.3 1.1 .92 .92 .96 2.8 1.8 1.7 1.2 .96 .80 .80 .85 47 6.8 3.2 2.3 5.7 35 17 6.7 4.2 3.1 3.2 23 46 16—— 240.51 8.02 47 .80 477 2.47 2.75 189 RIO ORANDB DB LOIZA BASIN 50051150 QUBBRADA BLANCA AT BL JAOUAL, PR—Continued WATER QUALITY RECORDS PERIOD OP RECORD.-- HATER YEARS JANUARY 1985 TO CURRENT YEAR STRBAMFLOW, SPECIFIC CON- TEMPERA- STRBAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCB TURB DATS TIMB INSTANTANEOUS DUCTANCB TURB (CFS) (UMHOS) (DBO C) (CFS) (UMHOS) (DBO C) FEB. 16 0916 2.34 270 24.5 JUL. 15 1436 1.35 290 26.0 MAR. 19 1453 15 280 26.0 AUG. 14 1023 .43 310 25.5 MAY 13 1217 1.18 300 25.5 SEP. 12 1415 1.21 300 28.0 190 RIO GRANDS DB LOIZA BASIN 50051150 QOBBRADA BLANCA AT BL JACKAL, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water yean 1985 to 1986 and water year 1989 to current year. PERIOD OF DAILY RECORD.— SUSPENDED-SEDIMENT DISCHARGEt October 1984 to SepteBber 1986 and from October 1989 to September 1991. EXTREMES FOR PERIOD OF DAILY RECORD.~ SEDIMENT CONCENTRATION! Maxim™ daily Mean, 7,300 ag/L Oct. 06, 1985; Minium daily Man, 1 Mg/Ii several days. SEDIMENT LOADSt MaxiauM daily mean, 4,940 tons (23,400 tonnes) May 17, 1985; Minimum daily 0.0 ton (0.0 tonne) several days. EXTREMES FOR WATER YEARS 1991.— SEDIMENT CONCENTRATION! Maxittim daily 1 mg/If several days. in, 255 ag/L Sep. 17, 1991; Ml ill Ml daily Man, SEDIMENT LOADSi MaxiauM daily Man, 277 tons (252 tonnes) Oct 20, 1990; Mln1«i» daily Man, 0 ton several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATBR YBAR OCTOBER 1990 TO SEPTEMBER 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) .74 .92 1.1 .94 1.1 .74 .57 .80 1.4 5.9 2.2 1.5 6.7 4.6 3.6 18 15 28 29 57 49 22 11 20 43 50 38 23 14 10 8.0 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MQ/L) (TONS/DAY) NOVEMBER MEAN DISCHARGE (CFS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MQ/L) (TONS/DAY) 1 1 1 1 2 1 1 1 2 13 4 5 15 9 7 92 44 123 55 194 176 19 6 80 198 229 113 42 9 5 5 .00 .00 .00 .00 .01 .00 .00 .00 .00 .34 .02 .00 .37 .20 .07 14 2.3 17 5.7 277 30 1.3 .18 17 40 35 12 2.8 .35 .14 .11 6.1 5.2 4.5 26 26 18 12 10 7.6 6.3 5.8 5.3 5.0 4.1 3.4 5.7 3.9 3.3 2.8 2.4 3.1 3.3 2.5 2.1 2.0 2.5 5.9 9.2 5.1 16 5 5 5 220 56 55 36 24 17 12 8 7 7 6 6 11 5 4 3 3 5 4 2 2 2 3 13 27 11 46 .09 .07 .06 40 4.9 2.6 1.2 .62 .33 .20 .12 .09 .09 .06 .05 .27 .06 .03 .02 .02 .06 .03 .01 .02 .02 .01 .39 1.6 .38 2.7 6.8 7.9 19 11 5.3 3.7 3.0 2.7 2.5 2.3 2.0 1.9 1.9 13 6.2 3.7 2.7 2.3 2.0 1.9 1.9 1.7 1.8 1.8 1.6 1.4 1.4 1.4 2.7 3.7 47 15 20 120 22 12 6 4 4 3 3 2 2 2 42 13 7 3 2 2 2 2 2 2 2 2 2 2 2 5 9 206 .32 .88 15 .70 .17 .06 .04 .04 .02 .02 .02 .01 .01 2.8 .25 .06 .03 .01 .01 .01 .01 .00 .00 .00 .00 .00 .00 .00 .04 .13 35 TOTAL 467.81 455.89 215.1 56.10 168.2 55.64 191 RIO ORANDB Ml LOIZA BASIN 50051150 QOBBRADA BLANCA AT BL JAGOAL, PR—Continued 8BOIMBNT DISCHARGB, SUSPENDED (TONS/DAY), WATER YBAR OCTOBER 1990 TO SBPTBMBBR 1991 DAY 1 2 3 4 5 C 7 8 9 10 11 12 13 14 15 1C 17 18 19 20 21 22 23 24 25 2C 27 28 29 30 31 MBAN DISCHAROB (CVS) 1C 7.9 5.5 4.2 11 8.9 8.2 8.9 7.7 7.8 C.3 5.4 4.8 4.3 4.4 4.0 3.5 3.2 2.9 2.7 2.5 2.3 2.3 2.0 2.C 2.4 2.2 1.9 1.9 1.9 2.8 CONCBN- SEDIMENT TRATION DISCHAROB (MQ/L) (TONS/DAY) JANUARY 4C 5 2 2 34 21 11 1C 12 15 9 7 5 3 3 3 3 3 2 2 2 2 2 2 2 2 2 2 2 2 4 2.3 .12 .04 .02 2.5 .58 .25 .53 .26 .37 .16 .10 .06 .04 .04 .03 .02 .02 .02 .02 .02 .02 .02 .02 .00 .02 .02 .01 .01 .01 .03 MBAN DISCHAROB (CPS) MBAN CONCEN- TRATION DISCHARGE (MQ/L) (TONS/DAY) 2.C 2.3 2.5 2.3 8.C 5.0 2.7 2.0 1.6 2.3 C.3 17 15 5.4 3.7 2.4 2.0 1.8 3.3 2.2 2.0 1.7 1.5 l.C l.C 1.4 1.2 2.4 PBBRUARY 4 3 3 3 2C 10 5 2 2 3 8 74 50 7 5 4 2 2 3 2 2 2 2 2 2 2 2 8 .02 .02 .01 .01 1.8 .17 .03 .02 .00 .02 .19 11 2.5 .13 .04 .02 .00 .00 .03 .00 .01 .00 .00 .00 .00 .00 .00 .oc MBAN DISCHARGE (CPS) 1.9 1.5 1.8 1.8 1.7 7.5 8.C 15 5.8 3.4 2.8 2.2 1.9 1.8 l.C 1.3 1.2 1.5 1.7 1.1 1.3 2.5 1.9 1.3 1.0 .92 1.2 .87 .75 .72 .74 MBAN CONCBN- SEDIMENT TRATION DISCHARGB (MG/L) (TONS/DAY) MARCH 3 2 3 2 2 18 23 51 13 5 4 4 2 2 2 2 2 2 2 2 2 3 2 1 1 1 1 1 1 1 1 .01 .00 .00 .01 .01 .55 .94 3.2 .22 .05 .03 .02 .02 .01 .00 .00 .00 .00 .01 .00 .00 .02 .01 .00 .00 .00 .00 .00 .00 .00 .00 TOTAL 152.4 7.C6 104.4 1C. 08 79.30 5.11 192 RIO GRANDS DB LOIZA BASIN 50051150 QOBBRADA BLANCA AT EL JACKAL, PR—Continued SBDIMBNT DISCHARGE, SUSPENDED (TONS/DAY), WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) .70 .71 .71 .67 .72 .77 .70 2.8 1.4 1.5 1.1 1.2 .93 .79 1.2 1.3 .87 1.3 1.1 .80 .73 .73 .65 .64 .59 .56 .54 .50 .46 .42 MEAN OONCBN- SBDIMBNT TRATION DISCHARGE (MG/L) (TONS/DAY) APRIL .00 .00 .00 .00 .00 .00 .00 .04 .00 .00 .00 .00 .00 .00 .00 .00 .00 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 MEAN DISCHARGE (CFS) .42 .42 .52 .46 .43 .45 .52 .72 .99 .80 3.5 4.5 1.4 .77 .61 .61 .68 2.9 1.3 .76 4.7 6.7 1.5 .86 9.2 3.2 1.3 .82 .63 .57 .53 MEAN CONCBN- SBDIMBNT TRATION DISCHARGE (MQ/L) (TONS/DAY) MAY 1 1 1 1 1 1 1 1 1 1 9 8 2 1 1 1 1 5 1 1 12 15 2 1 14 6 1 1 1 1 1 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .31 .12 .01 .00 .00 .00 .00 .04 .00 .00 .55 .39 .00 .00 .52 .06 .00 .00 .00 .00 .00 MEAN DISCHARGE (CFS) MEAN CONCBN- SBDIMBNT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 1.3 .92 .66 .57 1.8 1.8 1.9 1.1 .79 .66 .90 2.8 1.4 .81 .65 .54 .48 .69 .57 .52 2.4 1.2 .87 .88 .76 .56 .94 .70 .89 12 2 1 1 1 3 2 1 1 1 1 1 5 1 1 1 1 1 1 1 1 5 1 1 1 1 1 1 1 1 192 .01 .00 .00 .00 .02 .01 .00 .00 .00 .00 .00 .03 .00 .00 .00 .00 .00 .00 .00 .00 .08 .00 .00 .00 .00 .00 .00 .00 .00 75 TOTAL 27.09 0.05 52.77 2.00 72.06 75.15 193 RIO GRANDB DB LOIZA BASIN 50051150 QUEBRADA BLANCA AT BL JAGUAL, PR—Continued SEDIMENT DISCHARGE, SUSPBNDBD (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) •JULY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 74 24 6.5 4.5 2.8 2.0 1.4 1.2 1.2 1.1 .90 .84 .78 .72 16 52 14 4.6 2.6 2.3 1.3 .91 .71 1.6 1.0 .61 .58 .59 .52 5.2 1.4 227.86 1895.78 242 55 14 7 4 2 1 1 1 1 1 1 1 1 103 176 37 9 4 3 1 1 1 2 1 1 1 1 1 12 2 —— 64 3.9 .26 .09 .03 .01 .00 .00 .00 .00 .00 .00 .00 .00 19 36 1.7 .14 .03 .03 .00 .00 .00 .01 .00 .00 .00 .00 .00 .35 .01 125.56 1019.98 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) AUGUST .66 .52 .50 .44 .42 .67 .53 .44 .41 .38 .39 .39 .41 .59 .80 .75 1.0 1.4 .92 .74 .93 13 3.6 2.0 1.2 .89 29 16 4.6 2.6 2.1 —— 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 94 6 3 1 1 204 20 2 2 2 2.0 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 6.7 .09 .01 .00 .00 55 1.3 .03 .02 .01 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 2.1 1.8 1.3 1.3 1.1 .92 .92 .96 2.8 1.8 1.7 1.2 .96 .80 .80 .85 47 6.8 3.2 2.3 5.7 35 17 6.7 4.2 3.1 3.2 23 46 16 4 2 1 1 1 1 1 1 3 3 1 1 1 1 1 1 255 16 5 4 16 213 56 8 2 2 3 67 209 50 .02 .01 .00 .00 .00 .00 .00 .00 .02 .00 .00 .00 .00 .00 .00 .00 60 .38 .05 .02 .64 43 3.7 .15 .03 .02 .04 10 35 2.5 88.28 65.16 240.51 155.58 194 RIO GRANGE DB LOI2A BASIN 50051150 QUEBRADA BLANCA AT EL JAOUAL--Continued HATER QUALITY DATA, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1990 18... DEC 18... 31... 31... PEB 1991 12... 12... JUN 30... 30... JOL 01... 01... 15... 15... ADO 27... 27... SEP 17... 22... 22... 28... TIME 2015 1620 0430 0537 1808 1845 1255 1425 1231 1330 1920 2035 1518 1933 1120 1555 1710 1720 STREAM- FLOW, INSTAN- TANEOUS (CFS) 70 45 83 76 68 61 155 125 62 107 77 83 173 73 118 124 96 74 SEDI- MENT, SUS- PENDED SEDI- MENT, DIS- CHARGE, SUS- PENDED (MQ/L) (T/DAY) 414 696 846 834 468 394 2290 790 190 107 1400 274 1230 228 851 1200 578 226 78 85 189 171 86 65 958 266 32 31 291 61 574 45 271 401 150 45 BED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 96 90 94 98 97 94 97 100 85 98 93 91 83 84 96 99 91 OIA«-l0t VlfeWMH IA IA IA IA HO • -J M -I W0t MM M * MO IA !0tMVIHH MHMMM I . . . . . ..... ..... ..... .... IWWOIAM w<»iewH IAAWVIH MUU-JM •» M IA IA ff > ft l?| £sl • MM fi • '2n VI *• e •» o-J BE H H VI 01 . . W h» • M 0t *> M* *>M • H O H VI IA WO W IA . . H H • IA IA« IA • KM* IA0I -I O HO W IA 0t 01 I weo»0t0t •» IA *• VIVI-]** WKHHW W0t-IW0< VI KHHMM MMMMM *> 0t •»! 0« •» 0t M W 0t H C| MWwk^l ^I^IWHW H M VI VI VO W *> VO VO *> O VO •» M Z I I I M H> H> I I I ... I I I 0t H fc MMVI*-] W*ptflW'»l tJ * O IA MWOW-1 HKHMW WHHHK 0t0t*iM «WWW0t • Vl M W h* M H KHMMK HHK HKKHH H M *• M *> •»0»0»H0I« eMOWK OtJH>«VO WWOHH MWMOH VI VI M M CO w w 0t in MM W VI0IWH h» H H H M WH CO h» 0t IA .** H>H>H> n es 1 ,M « ^« ** —— » .. -^ i,i-i 1 i ? ill MHKMM H MM0|M •» *• CO CO CO IA *• *• •» M CO VI M •» HO0I 0t MWW0IO Moklhlh IhlhVICOH ifc W >J «J CO d CO^iCO •J0t0lCO -J-JOH-J Q S K O ^ 4eWh* «O9• 4 i F H f H ?1 ! g|8 is I = °i ;p °" Ei ![« it S H "< ?l |g ^S J S'l ? n i H 9 ^g g", H* • » H- I H • H K ik K f ? I ! t t I H- B ? I I ' g • § n ^ I 8 * § i ^ r * * i a S P 1 ? 1 ? 198 RIO GRANDS DB LOIZA BASIN 50051180 gUBBRADA 8ALVATIBRRA NBAR SAN LORBNZO, PR-Continued SBDIMBNT DISCEARGB, SUSPENDED (TONS/DAY), WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) 11 6.2 3.8 2.9 6.0 8.4 6.9 7.9 6.4 4.3 2.9 2.5 2.5 2.2 2.1 2.3 2.1 1.8 1.7 1.7 1.7 1.4 1.3 1.3 1.2 1.1 1.1 1.1 1.1 1.0 1.4 CONCEN- SBDIMBNT TRATION DISCHARGE (MG/L) (TONS/DAY) JANUARY 59 35 25 18 50 61 38 52 42 34 33 32 32 31 28 23 19 15 11 10 10 8 8 8 7 6 6 13 9 6 8 2.0 .59 .27 .13 1.8 1.6 .70 1.3 .77 .41 .25 .22 .22 .18 .15 .13 .11 .08 .05 .04 .04 .04 .03 .02 .02 .02 .02 .04 .02 .02 .03 MEAN DISCHARGE (CFS) MEAN CONCBN- SBDIMBNT TRATION DISCHARGE (MG/L) (TONS/DAY) 1.6 1.3 1.3 1.3 3.8 3.2 2.4 1.6 1.6 1.8 7.9 8.0 10 3.4 2.2 1.7 1.3 1.5 4.4 2.3 1.7 1.4 1.5 1.2 1.2 1.4 1.1 2.6 FEBRUARY 8 6 6 6 24 26 22 20 20 20 55 55 83 28 13 11 10 12 20 11 9 6 7 5 5 5 5 16 .03 .02 .02 .02 .53 .28 .15 .09 .08 .10 1.8 3.1 2.9 .30 .07 .05 .03 .05 .25 .06 .05 .03 .02 .01 .01 .02 .01 .19 MEAN DISCHARGE (CPS) 1.8 1.2 1.2 1.5 1.5 4.1 2.0 4.2 2.3 1.2 1.1 1.1 1.0 1.3 1.3 .97 .82 1.1 1.2 1.0 1.1 2.3 2.0 1.2 1.0 1.8 2.6 1.1 .83 .83 .83 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MARCH 15 10 10 10 10 27 13 30 20 18 13 11 10 8 6 6 6 6 6 5 5 5 5 5 5 11 14 5 5 5 5 .09 .04 .02 .03 .04 .39 .08 .50 .12 .06 .04 .03 .02 .02 .02 .02 .02 .02 .01 .02 .02 .03 .02 .01 .02 .16 .15 .02 .02 .02 .02 TOTAL 99.3 11.30 74.7 10.27 47.48 2.08 199 RIO ORAMDE DE LOIZA BASIN 50051180 QDEBRADA 8ALVATIBRRA NEAR SAN LORENZO, PR-Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO 1991 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CPS) (MQ/L) (TONS/DAY) (CPS) (MQ/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 .81 .75 .78 .73 .72 .83 .82 3.9 3.2 2.3 2.1 1.8 1.6 1.5 1.3 1.4 1.1 1.2 1.4 1.0 .93 .90 .80 .67 .67 .88 .78 .73 .67 .67 APRIL 5 5 5 5 4 4 3 9 9 13 14 11 10 8 8 8 7 6 6 6 6 5 5 5 5 5 5 4 4 4 —— MEAN DISCHARGE (CPS) MAY .02 .02 .02 .01 .00 .00 .00 .09 .08 .09 .08 .06 .05 .03 .02 .04 .02 .01 .02 .02 .02 .02 .01 .00 .00 .01 .02 .00 .00 .00 .67 .67 .94 .81 .75 .75 .75 1.1 1.4 1.4 4.9 4.7 1.0 .72 .84 .65 .99 2.6 1.6 .79 1.2 4.2 1.2 .83 4.1 2.9 1.6 1.1 .83 1.1 1.3 32 35 11 11 11 11 12 18 10 10 10 21 6 3 20 12 10 10 10 6 7 .00 .00 .01 .00 .00 .00 .00 .01 .02 .02 1.3 .61 .03 .02 .02 .03 .04 .14 .04 .02 .04 .32 .02 .01 .33 .10 .05 .04 .02 .02 .04 2.2 2.1 1.3 1.0 2.6 1.5 1.3 1.1 .78 .48 .90 2.2 .87 .50 .50 .42 .47 .60 .51 .42 1.9 2.1 .77 .74 .65 .49 .67 .75 .60 23 CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 8 9 10 11 11 10 10 10 10 10 9 20 6 13 14 5 5 5 5 5 5 5 188 .04 .06 .03 .02 .08 .04 .04 .02 .01 .01 .02 .16 .02 .00 .00 .00 .00 .00 .00 .00 .18 .11 .02 .01 .00 .00 .01 .01 .00 44 TOTAL 36.94 0.76 48.39 3.30 53.42 44.89 200 RIO CRANES DB LOIZA BASIN 50051180 QUEBRADA SALVATIBRRA NBAR SAN LORBNZO, PR-Continued SBDIMBNT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR MEAN DISCHARGE (CFS) 52 6.7 2.3 2.2 1.3 .85 .66 .66 .65 .61 .55 .51 .33 .33 13 71 14 7.8 4.2 3.5 1.8 1.2 .80 2.4 1.4 .94 .85 .83 .80 4.4 1.8 200.37 1823.29 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JULY 372 27 11 10 10 5 5 5 5 5 5 5 5 5 25 430 37 31 30 25 15 8 5 14 9 6 6 6 5 23 11 —— 201 .75 .07 .06 .04 .01 .01 .00 .00 .00 .00 .00 .00 .00 .47 156 1.6 .66 .34 .23 .08 .03 .01 .11 .04 .02 .02 .02 .01 .48 .08 362.14 2449.97 MEAN DISCHARGE (CFS) MEAN CONCBN- SBDIMBNT TRATION DISCHARGE (MG/L) (TONS/DAY) AUGKJST .87 .71 .70 .57 .47 1.1 .88 .56 .46 .47 .48 .47 .48 3.0 4.2 1.0 2.6 4.9 1.8 1.2 1.6 15 7.6 2.0 1.1 .77 39 19 7.3 3.2 2.9 6 5 5 5 5 5 5 5 30 5 5 5 5 21 25 8 17 33 20 14 11 112 53 19 14 11 413 131 49 22 14 .02 .01 .01 .00 .00 .01 .01 .00 .03 .00 .00 .00 .00 .46 .47 .02 .27 .50 .11 .04 .05 9.0 1.3 .11 .04 .02 175 7.9 1.0 .22 .10 MEAN MEAN CONCBN- SEDIMENT DISCHARGE THATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 1.6 1.3 .87 .73 .63 .69 .98 .77 5.3 2.1 1.4 .72 .60 .54 .42 .38 48 8.5 2.4 1.1 2.7 44 17 8.2 4.1 2.1 1.2 2.9 27 16 11 10 10 8 6 6 6 5 38 17 7 5 4 4 4 4 364 37 16 6 18 267 34 17 14 12 10 18 191 113 .05 .03 .02 .02 .01 .01 .01 .02 1.0 .12 .03 .01 .00 .00 .00 .00 157 .91 .12 .02 .29 102 1.8 .39 .15 .07 .03 .24 16 5.3 126.39 196.70 204.23 285.65 201 RIO GRANDB DB LOIZA BASIN 50051180 QUBBRADA SALVATIERRA NEAR SAN LORENZO, PR—Continued WATER QUALITY DATA, WATER YRAR AUGUST 1990 TO SBPTBHBBR 1991 PARTICLB-SIZB DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1990 16... 17... 18... DEC 31... JUL 1991 15... AUO 27... SBP 17... 22... DATB OCT 1990 16... 17... 18... DEC 31... JUL 1991 15... AUO 27... SBP 17... 22... TIME 1331 1646 2000 0400 1947 1546 0916 1901 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 72 70 59 32 91 80 54— DIS- CHARGE, INST. CUBIC FEET PBR SECOND 251 73 1321 91 60 340 172 46 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 78 74 70 45 — 94 69— SEDI- MENT, SUS- PENDED (MG/L) 7090 936 2440 3470 5900 3311 9648 6547 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 97 98 92 64 99 95 87 100 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 4800 180 870 850 956 2700 4480 813 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 98 99 98 78 100 97 96 100 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 28 37 32 16 53 26 18 45 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 100 100 88 100 99 100 100 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 42 50 38 21 62 47 26 63 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 100 100 100 96 100 100 100 100 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 59 62 46 22 82 65 40 93 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 100 98 100 100 100 100 202 RIO QRAKDB DB LOIZA BASIN 50051180 QUBBRADA SALVATIERRA NEAR SAN LORBNZO—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATB OCT 1990 16... 16... 16... 17... 17... 18... 18... 18... 20... 20... 24... 24... 24... DEC 31... JAN 1991 08... AUQ 27... 27... SEP 17... 17... 22... 22... TIME 1338 1345 1352 1726 1736 1746 2010 2130 2316 2346 2131 2221 2311 0500 1124 1521 1656 0841 0952 1441 1541 STREAM- FLOW, INSTAN- TANEOUS (CFS) 200 162 133 62 59 102 166 198 605 475 198 122 106 162 141 101 88 379 77 275 SEDI- SUS- PENDBD (MG/L) 7200 6800 6000 776 774 595 2200 920 4100 2520 1000 1200 450 1450 690 5110 1480 2290 1550 727 2240 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 3900 3000 2200 130 122 160 990 490 670 3230 530 400 130 630 17 2000 403 544 1600 151 1700 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 99 98 99 99 84 92 86 83 88 91 74 93 85 99 79 96 87 85 81 96 RIO GRANDB DB LOIZA BASIN 203 50051310 RIO CAYAOOAS AT CBRRO OORDO, HI LOCATION.—Lat 18«09'13-, long 65«57'20», Hydrologie Unit 21010005, at downstream aid* of bridge on Highway 912, at Barrio Cerro Oordo, 2.8 mi (4.5 km) couth of San Lorenxo. DRAINAOB AREA.--10.2 Mi' (26.4 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—October 1977 to current year. GAGE.—Water-stage recorder and crest-stage gage. Elevation of gage is 490 ft (150 m), fro* topographic map. Prior to Oct. 1, 1983, at site 2,000 ft (610 m) downstream at different datum. REMARKS.—Records poor. Sand removal at a commercial level is practiced at times during the year. This takes place about one hundred feet downstream from the low water control. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.—14 years (1978-91), 44.5 ftJ/« (1.260 •?/•), 59.24 in/yr (1,505 mm/yr), 32,240 acre-ft/yr (39.75 hmVyr)j median of yearly mean discharges, 40.0 ftV« (1.13 mV«), 29,000 acre-ft/yr (35.8 hmVyr). EXTREMES FOR PERIOD OF RECORD.—maximum discharge, 13,200 ft1/! (374 mV«), Aug. 31, 1979, gage height, 9.44 ft (2.877 m), Bite and datum then in use, from rating curve extended above 1,000 ft'/i (28.3 •?/•) on basis of •lope-area measurement; minimum discharge, 7.1 ft'/« (0.201 mV«), Feb. 4, May 3, 1981; Apr. 12, 13, IS, 17, 1983. EXTREMES FOR CURRENT YEAR.--Peak dischargee greater than base discharge of 2,500 ft'/i (70.8 •?/•) and may!mum (*)i Discharge Gage height Discharge Gage height Date Time (ft'/>) (mV«) (ft) (m) Date Time (ft*/«) (mV«) (ft) (m) Oct. 21 0045 *1,150 32.6 *10.30 3.139 Minimum discharge, 8.6 ftVs (0.244 mV«), June 27. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 19 17 17 16 15 15 15 14 17 23 19 15 25 16 16 22 17 29 38 50 219 39 32 70 120 91 56 50 46 38 34 1210 39.0 219 14 2400 3.83 4.41 1990 1991 34 32 29 42 46 33 30 29 28 27 26 26 26 25 25 25 24 24 25 24 24 24 23 23 23 25 25 23 23 39 —— 832 27.7 46 23 1650 2.72 3.03 TOTAL 7383.5 TOTAL 7305.7 26 26 26 25 22 22 21 21 21 21 21 21 20 27 26 23 20 20 20 20 20 20 20 19 19 19 20 20 22 23 65 716 23.1 65 19 1420 2.26 2.61 MEAN MEAN 26 21 20 20 21 20 21 23 22 22 21 21 19 20 22 20 18 18 17 17 17 16 16 16 16 16 16 16 16 15 17 586 18.9 26 15 1160 1.85 2.14 20.2 MAX 20.0 MAX 17 16 19 17 27 33 26 19 19 19 27 32 31 22 21 20 19 19 23 22 24 21 19 20 20 19 18 19 —— —— —— 608 21.7 33 16 1210 2.13 2.22 219 MIN 219 MIN 18 18 19 18 18 28 22 21 19 18 17 16 16 16 16 15 15 16 17 16 15 18 17 15 15 15 15 15 14 14, 14 526 17.0 28 14 1040 1.66 1.92 8.6 AC-FT 9.0 AC-FT 14 14 14 13 13 13 13 14 13 18 14 14 13 13 13 15 13 13 13 12 12 13 12 12 13 12 12 12 12 12 —— 394 13.1 18 12 781 1.29 1.44 14650 14490 11 11 11 11 12 9.8 9.9 10 12 9.7 9.3 10 9.6 9.4 9.4 9.4 9.6 13 11 12 13 16 11 10 15 13 10 9.6 9.4 9.2 9.0 335.3 10.8 16 9.0 665 1.06 1.22 CFSM 1.98 CFSM 1.96 11 11 9.4 9.4 11 15 13 11 10 10 11 12 11 .9 .6 .4 .1 .2 .2 .1 1 .7 .5 .8 .4 9.0 11 10 13 129 —— 430.7 14.4 129 9.0 854 1.41 1.57 IN. 26. IN. 26. 194 25 19 17 16 15 14 15 14 14 14 13 13 13 22 48 22 17 17 18 15 15 16 17 15 14 15 14 14 18 18 711 22.9 194 13 1410 2.25 2.59 93 64 15 15 14 14 14 15 14 13 13 12 12 12 12 12 11 9.8 14 13 11 10 15 22 14 12 11 10 41 28 14 14 12 448.8 14.5 41 9.8 890 1.42 1.64 11 11 11 10 10 10 10 10 12 12 11 10 9.7 9.5 9.3 9.4 51 17 12 10 14 20 27 18 14 12 15 38 68 26 —— 507.9 16.9 68 9.3 1010 1.66 1.85 204 RIO QRANDB DB LOIZA BASIN 50051310 RIO CAYAOUAS AT CBRRO OORDO, PR—Continued HATER QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR DATE TIME FEB. 20 1213 MAR. 19 1120 NAY. 15 1050 JUN. 21 1116 STRBANFLON, INSTANTANBOOS (CFS) 20.9 16.5 9.58 12.0 SPECIFIC CON- TBMPBRA- DDCTANCB TURK (DNHOS) (DBQ C) DATE 139 145 145 135 22.0 23.0 24.5 25.3 JUIi. 17 1202 ADO. 15 1008 SEP. 13 1357 STREAMFLON, INSTANTANBOOS (CFS) 21.2 11.0 9.75 SPECIFIC CON- DUCTANCE (UMHOS) 130 140 150 TEMPERA- TURE (DBQ C) 25.5 24.5 27.5 RIO QRANDE DB LOIZA BASIN 205 50051800 RIO ORANDB DB LOIZA AT HWY 183 NBAR SAN LORBNZO, PR LOCATION.--Lat 18«11'09", long 65«57'42», Hydrologie Unit 21010005, at upitream tide of bridge on Highway 183 by-pa», 0.4 mi (0.6 km) Bouth from Plata de San Lorenzo, 1.4 mi (2.2 km), aouthweBt from Eicuela Rafaal Colon Oarcia and 2.0 mi (3.2 km) northwest from Eicuela Segunda Unidad de Carlo* Zayai. DRAINAOB ARBA.—25.0 mi* (64.8 km*). WATER-DISCHARGE RECORDS PBRIOD OF RECORD.--February 1990 to currant year. QASB.—Water-Btage recorder. Elevation of gag* i« 262 ft (80 m), from topographic map. REMARKS.—Record* fair except thoie for estimated daily discharge*, which are poor. Water purification plant located about 0.2 mi (0.3 km) upitream from gage. Gage-height and precipitation satellite telemetry at itation. EXTREMES FOR PBRIOD OF RECORD.--Maximum discharge, 7,510 ft5/* (213 •?/•), Oct. 20, 1990, gage height, 16.60 ft (5.060 m), from rating curve extended above 2,000 ft5/* (56.6 •?/•) on baiii of itep-backwater analyiii; minimum daily discharge, 15 ft3/* (0.425 •*/•), May 25, 30, 1990. EXTREMES FOR PBRIOD FEBRUARY TO SEPTEMBER 1990 AND WATER YEAR 1991.—Peak discharge greater than bate discharge of 2,500 ft'/* (70.8 •?/•) and maximum (*) i Discharge Gage height Discharge Qage height Date Time (ft3/*) (•?/•) (ft) (m) Date Time (ft5/*) (•?/•) (ft) (m) June 14,1990 1945 2,590 73.3 12.12 3.694 Oct. 20,1990 2350 +7,510 213 *16.60 5.060 Aug. 10 0900 3,730 106 13.23 4.032 Oct. 24 2125 4,180 118 13.68 4.170 Aug. 28 1800 +4,290 121 +13.80 4.206 June 30,1991 1400 4,590 130 14.06 4.285 Oct. 16,1990 1445 2,590 73.3 12.12 3.694 July 1 0545 2,690 76.2 12.22 3.725 Minimum daily discharge, 15 ft3/« (0.425 »'/•), May 25, 30, 1990; 17 ft5/* (0.481 mV«) June 26, 1991. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAILY MEAN VALUES DAY OCT NOV DBG JAN FBB MAR APR MAY JON JUL ADO SBP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. e Estimated e46 e38 e35 e30 e29 e40 eSO e65 eSO 46 36 32 33 41 37 32 35 41 35 39 60 64 57 204 60 48 41 36 —— —— 1360 48.6 204 29 2700 1.94 2.02 40 37 33 32 30 28 27 26 29 35 34 46 50 130 64 56 56 40 34 33 30 27 31 29 28 26 27 29 32 30 29 1178 38.0 130 26 2340 1.52 1.75 27 26 27 26 27 25 23 22 22 21 20 21 42 37 24 23 24 23 26 26 21 19 19 19 53 76 49 27 22 19 —— 836 27.9 76 19 1660 1.11 1.24 19 20 19 19 19 18 18 22 154 247 118 44 34 36 30 27 25 24 21 20 17 19 19 18 15 30 25 20 19 15 17 1148 37.0 247 15 2280 1.48 1.71 18 19 18 19 41 53 39 24 38 26 21 19 19 515 399 136 77 54 46 78 50 41 38 52 263 123 72 52 44 40 —— 2434 81.1 515 18 4830 3.25 3.62 57 49 38 42 41 138 77 58 42 41 39 36 37 52 55 54 49 70 135 62 44 36 31 48 224 222 89 55 46 41 37 2045 66.0 224 31 4060 2.64 3.04 36 40 40 46 56 44 54 210 81 800 193 102 115 82 67 61 54 51 51 46 43 46 49 53 47 50 38 526 134 60 45 3320 107 800 36 6590 4.28 4.94 40 39 39 55 35 31 29 33 32 34 28 30 52 84 79 111 76 85 78 45 39 36 99 58 44 103 70 143 94 70 —— 1791 59.7 143 28 3550 2.39 2.67 206 DAY OCT RIO GRANDE DB LOIZA BASIN 50051800 RIO GRANDB DB LOIZA AT BNY 183 NEAR SAN LORENZO, PR—Continued DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES NOV DBC JAN FBB MAR APR MAY JUN JOL AUQ SBP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-PT CPSM IN. 65 51 57 50 46 41 37 45 135 133 88 60 142 117 97 353 144 301 724 410 1390 243 170 484 810 800 398 269 213 192 188 8253 266 1390 37 16370 10.6 12.28 163 152 138 359 320 199 152 130 113 105 96 89 84 79 76 76 74 71 70 69 66 70 64 60 60 74 90 83 64 159 --- 3405 113 359 60 6750 4.54 5.07 102 84 122 95 70 61 56 54 53 51 55 49 42 229 120 86 70 61 56 56 52 53 51 52 48 45 47 54 70 78 566 2688 86.7 566 42 5330 3.47 4.00 124 77 65 59 82 80 86 90 89 79 69 70 66 67 80 65 55 50 49 47 46 44 46 44 48 46 46 46 45 43 47 1950 62.9 124 43 3870 2.52 2.90 54 46 56 50 121 129 81 45 40 42 111 133 155 68 60 51 46 45 80 74 94 69 58 59 59 58 49 59 —— 1992 71.1 155 40 3950 2.85 2.96 58 50 53 67 63 106 89 93 67 54 49 50 45 47 45 40 37 38 47 36 34 46 46 35 32 31 31 30 •34 •29 •29 1511 48.7 106 29 3000 1.95 2.25 •29 •30 •30 •28 •28 •28 •27 •35 •39 •57 •38 •44 •34 •29 •55 •46 •34 •37 •32 •26 •26 •28 •26 •24 •27 •26 •25 •23 •22 •21 —— 954 31.8 57 21 1890 1.27 1.42 •22 •21 •22 •30 •26 •25 •27 •25 •24 •22 •23 •55 •28 •23 •24 •26 •23 •39 •29 •30 •54 57 31 23 197 62 32 26 22 21 20 1089 35.1 197 20 2160 1.41 1.62 25 30 22 23 28 52 42 33 29 26 32 82 38 27 31 23 20 20 19 19 26 25 21 22 21 17 19 24 30 609 —— 1435 47.8 609 17 2850 1.91 2.14 597 143 83 71 53 47 40 34 33 33 27 25 25 24 75 371 117 69 56 65 50 42 44 56 48 38 42 40 39 64 51 2502 80.7 597 24 4960 3.23 3.72 38 36 33 29 28 30 29 25 24 22 23 20 22 26 32 26 49 62 40 29 61 145 95 49 38 35 118 170 71 56 46 1507 48.6 170 20 2990 1.94 2.24 43 60 35 31 29 33 28 31 67 55 49 37 34 34 33 31 330 132 80 61 79 187 217 130 85 69 88 165 268 198 —— 2719 90.6 330 28 5390 3.63 4.05 WTR YR 1991 TOTAL 30005 MEAN 82.2 MAX 1390 MIN 17 AC-PT 59510 CPSM 3.29 IN. 44.65 WATER QUALITY RECORDS PERIOD OP RECORD.-- OCTOBER 1990 TO SEPTEMBER 1991 STRBAMFLOW, DATE TIME INSTANTANEOUS (CPS) PEB. 20 1420 MAR. 20 1352 MAY 14 1236 JUN. 19 1324 49.0 33.7 18.0 17.1 SPBCIPIC CON- TBMPBRA- DUCTANCE TORE (UMHOS) (DBG C) WATER QUALITY RECORDS 174 175 180 180 24.5 27.0 29.0 31.5 DATE TIME JUL. 15 1104 AUG. 15 0834 SBP. 12 1040 STREAMFLON, INSTANTANEOUS (CPS) 19.3 35.8 32.8 SPECIFIC CON- TBMPERA- DUCTANCB TORE (UMHOS) (DBG C) 180 190 170 28.0 28.0 28.0 so 10 so so H O VI W O VI VI * UUMMMM H M M WOt O Mi >!9lM * so > * S09lU)0»* •O -J -J« O • * so tfl OH O M so MM H H * . H « Wl S09l H H 9l • VI MH O M W -O o W W H M . . * H W -J -JMMHSO* H SOHHHHH **OOtflH-O tfltflMOOH U) * U)***H tfl>l*O HHHHH HHHHH H l-« H H l-« H H H 10 M tfl 9l H H H Q MMW9I* &WW** ** tfl tfl tfl 9l-O so H 9l tflU)9l>le* < •s M< I ft ft g SO 0 ft & o 555! 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SO H 2 * O w & 8r 3 Q 3 \ H ! sr s & 0 0 0 Ml H « M ^f "»& »£s s& B ?§& s| oi tfl H U1Q O • OOMi'l 0 Ml CT, *• • m Pf ft • t*° o H S!!r .^m S"r H ?? Ml ° 1 fT !* t AT £ Q. pi i& 2 krt n 2 ft i • P 1 ?P 0 Ml i*s * so Ml ft KI-> SO 00 .. tfl tfl « -J tfl U) -J« 0* tfl • O * (-* tfl >1 SO 0» tfl tfl tfl 91 91 tfl tfl 91 91 91 9l>10»SOe* 9| 9| 9|-O «J 91 91 91 91 A -JVOOOI->H «JO»OMH -OWUI W Ul>lv09l>l * O M tfl M 91 00 tfl tfl tfl tfl OOH*>1>1 (->!-• H> W M«0 • * 91* O* 91 -J SO l-» H» tfl -O tfl « • SO • • ... . * H M *> H 0* O tfl * M tfl 0i e» 01 01 01 -o e» o so-o etui ui tfi 9i 01 01 01 01 • HOOMW -O 91 H 01 -J M W*UIO»l * «J 91 K "J >]**** ***** **tfltfltfl * * * 0* 10 SO 0* M H H 91 O O Ul O H * i>i>iMi-> M w o o in tfi 01 01 01 «J -OH tfi tfi tfi tfi tfi tfi «J 0i o ^i o o ui in w ui9i>i * * «J * M S roo 208 RIO ORANDB DB LOIZA BASIN 50053025 RIO TDRABO ABOVB BORINQUBN, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1990 TO SEPTEMBER 1991 DATS TIME FEB. 19 1155 JUNE 25 1112 STRBAMFLOW, INSTANTANEOUS (CFS) 3.21 5.57 SPECIFIC CON- DUCTANCE (DMHOS) 152 175 TEMPERA- TURE (DBG C) 22.5 27.5 DATS TIME JULY 12 1223 AUO. 22 1030 STRBAMFLOW, INSTANTANEOUS (CFS) 5.63 29.2 SPECIFIC CON- DUCTANCE (UMHOS) 175 160 TEMPERA- TURE (DBG C) 27.5 24.5 RIO ORANDE DE LOIZA BASIN 50055000 RIO GRANDB DE LOIZA AT CAGUAS, PR 209 LOCATION.—Lat 18°14'33", long 66°00'34", Hydrologic Unit 21010005, on right bank 250 ft (76 m) upstream from bridge on Highway 189, 1.2 mi (1.9 km) downstream from Rio Turabo, and 1.8 mi (2.9 km) east of Plata de Caguas. DRAINAGE AREA.--89.8 mi* (232.6 km1 ). PERIOD OF RECORD.—1959 (low-flow December 1959 to current year. WATER-DISCHARGE RECORDS tsurement only), February to November 1959 (monthly measurements only), GAGE.—Water-stage recorder. Datum of gage is 143.28 ft (43.672 m) above mean sea level. REMARKS.—Records good except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGES.—31 years (1961-91), 220 ftVs (6.230 m>/s), 33.27 in/yr (845 mm/yr), 159,400 acre-ft/yr (196 bnVyr); median of yearly mean discharges, 210 ft1/* (5.95 •?/•). 152,000 acre-ft/yr (190 hmVyr). EXTREMES FOR PERIOD OF RECORD.—Maximum discharge, 71,500 ft3/* (2,020 ms/s), Sept. 6, 1960, gage height, 31.17 ft (9.501 m), from rating curve extended above 6,000 ft3/* (170 mVs) on basis of slope-area measurement; minimum daily discharge, 10 ft3 /* (0.283 mVs), Apr. 5, 10, 29, 1968. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 8,000 ftVs (226 mVs) and maximum (*)i Discharge (ftVs) (ms Gage height (ft) (m) Date Time Oct. 21 0050 *12,900 365 *15.27 4.654 Minimum daily discharge, 20 fts/s (0.566 mVs), Aug. 13. Discharge (ftVs) (mVs) Gage height (ft) (m) Date Til No other peak greather than base discharge. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JDN JUL AUQ SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 119 75 75 91 68 65 •128 64 • 144 •326 169 93 192 161 •479 •1400 397 679 843 508 3580 500 276 elOOO •1700 •1500 •750 •700 •700 •750 •300 17832 575 3580 64 35370 •200 185 164 399 460 287 192 180 156 144 136 128 122 117 113 115 115 105 102 102 97 112 100 89 83 91 122 137 93 187 —— 4633 154 460 83 9190 6.41 1.72 7.39 1990 1991 1.92 TOTAL 51010 TOTAL 55562 208 124 227 195 116 99 89 86 85 85 116 107 73 418 235 142 99 84 77 74 72 70 71 73 66 60 61 72 101 132 •1450 4967 160 1450 60 9850 1.78 2.06 MEAN 140 MEAN 152 377 207 147 126 141 208 165 164 180 150 140 124 131 117 136 128 106 97 89 85 80 76 74 73 72 74 70 69 68 68 66 3808 123 377 66 7550 1.37 1.58 MAX 3580 MAX 3580 89 71 77 75 182 270 165 87 76 71 221 243 383 132 102 86 75 73 141 103 123 99 77 77 76 76 65 72 —— 3387 121 383 65 6720 1.35 1.40 MIN 17 MIN 20 80 65 65 95 89 159 136 123 102 72 63 66 61 62 61 56 52 53 72 58 52 93 101 61 51 75 76 53 46 44 42 2284' 73.7 159 42 4530 .82 .95 AC-FT AC-FT 42 40 42 38 36 37 35 50 62 55 55 55 47 39 36 69 42 39 40 34 31 31 30 28 25 29 27 24 22 21 —— 1161 38.7 69 21 2300 .43 .48 101200 110200 22 23 24 21 26 26 26 26 32 37 59 133 47 29 30 27 26 44 43 33 39 84 43 31 •463 138 64 44 39 35 33 1747 56.4 463 21 3470 .63 .72 CFSM 1.56 CFSM 1.70 34 45 35 31 45 64 65 53 41 35 42 106 72 42 39 33 28 25 25 24 29 39 33 33 29 28 22 32 28 •1040 —— 2197 73.2 1040 22 4360 .82 .91 IN. 21.13 IN. 23.02 •1610 296 137 111 84 69 60 54 51 45 44 37 36 36 166 •1480 248 110 82 89 63 52 47 61 64 44 47 44 40 55 69 5431 175 1610 36 10770 1.95 2.25 46 39 37 35 31 34 38 29 26 25 23 23 20 25 42 29 53 107 53 36 59 235 217 73 49 38 •643 •421 122 77 64 2749 88.7 643 20 5450 .99 1.14 54 82 46 38 35 32 33 34 65 91 54 46 33 31 29 24 •1300 227 169 106 114 •487 429 209 123 95 89 204 727 360 5366 179 1300 24 10640 1.99 2.22 e Estimated 210 RIO ORANDB DB LOIZA BASIN SOOSSOOO RIO GRANDB DB LOIZA AT CAOOA8, PR—Continued WATER-QOALITY RECORDS PERIOD OV RECORD.--Water yeara 1959 to current year. PERIOD OP DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGEi October 1983 to Septeaber 1989. INSTRUMENTATION.-- USD-49 and automatic aediaant aaapler. EXTREMES POR PBRIOD OP DAILY RECORD.-- SEDIMENT CONCENTRATION i Maxiaua daily aean, 14,500 ag/L Nov 27, 1987; Minimum daily aean, 11 ag/L August 12, 1985. SEDIMENT LOADS i Maatiaua daily aean, 227,000 ton* (205,890 tonnea) Nov 27, 1987; Miniaua daily Bean, 1.3 tona (1.2) July 14, 1985. EXTREMES POR CURRENT YEAR.— SBDIMBNT CONCENTRATIONi Maatiaua daily aean, 691 ag/L October 23,1989 » Minima daily aaan, 12 ag/L October 27, 1989. SEDIMENT LOADS i Maatiaua daily aean, 2,830 tona (2,580 tonnea) Auguat 10, 1990 » ainiaua. daily 1.4 ton (1.3 tonnea) May 25, 1990. REVISIONS.— MEAN CONCENTRATION (ag/L)i On May 13, 1986 ia 1,550. SEDIMENT DISCHARGE (tona/day)i On May 13, 1986 ia 36,300. MATER-QUALITY DATA, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 01... DEC 11... PEB 1991 14... APR 11... JUN 25... AUG 22... TIME 0945 0920 0910 0845 1015 0910 DIS- CHARGE, INST. CUBIC FEET PBR SECOND 217 80 138 192 30 75 SPE- CIFIC CON- DUCT- ANCE (US/CM) 216 258 187 250 273 223 PH (STAND- ARD UNITS) 7.6 7.4 7.4 7.3 7.7 7.3 TEMPER- ATURE MATER (DBO C) 26.0 23.5 23.0 24.5 29.5 28.5 TUR- BID- ITY (NTU) 360 19 51 54 10 40 OXYGEN, DIS- SOLVED (MG/L) 7.3 7.7 8.0 7.0 7.0 8.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 89 90 93 84 91 110 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 22 10 21 19 15 19 COLI- PORM, PECAL, 0.45 UM-MF (COLS./ 100 ML) 25000 K27 4300 27000 490 K9100 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 4700 K170 720 3900 K20 700 DATE NOV 1990 01... DEC 11... PBB 1991 14... APR 11... JUN 25... AUG 22... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH NAT DI8- (MG/L TOT PLD SOLVED AS MG/L AS (MG/L CACO3) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 68 0 18 5.7 19 75 19 6.8 22 ALKA- SODIUM POTA8- LINITY CHLO- AD- SIUM, MAT WH SULPATB RIDE, SORP- DIS- TOT PET SULFIDE DIS- DI8- TION SOLVED FIELD TOTAL SOLVED SOLVED RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L 65 1 16 6.1 20 AS K) 1.9 1.9 2.5 CAC03 69 86 59 80 90 79 AS S) AS SO4) AS CL) <0.5 13 <0.5 13 11 21 20 18 non-ideal count RIO GRANDS DB LOIZA BASIN 50055000 RIO QRANDB DB LOIZA AT CAGDAS, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 21 1 SOLIDS, RESIDUE DATE NOV 1990 01... DEC 11... FBB 1991 14... APR 11... JDN 25... ADO 22... DATE NOV 1990 01... DEC 11... FBB 1991 14... APR 11... JDN 25... ADO 22... DATE NOV 1990 01... DEC 11... FBB 1991 14... APR 11... JDN 25... ADO 22... FLDO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 — — <0.10 — 0.10 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.70 0.40 0.30 0.50 2.3 1.6 IRON, TOTAL RECOV- ERABLE (DG/L AS FB) 26000 -- — 3500 -- __ SILICA, DIS- SOLVED (MG/L AS SI02) 31 — — 30 — 31 NITRO- GEN, TOTAL (MG/L AS N) 1.2 0.90 1.0 0.91 2.9 1.9 LEAD, TOTAL RECOV- ERABLE (DG/L AS PB) 9 — — 2 — — SDM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 151 — — 161 — 152 NITRO- GEN, TOTAL (MG/L AS N03) 5.3 4.0 4.4 4.0 13 8.5 MANGA- NESE, TOTAL RECOV- ERABLE (DG/L AS MN) 1700 — — 310 — — SOLIDS, DIS- SOLVED (TONS PER DAY) 88.5 — — 83.0 — 30.8 PHO8- PHORDS TOTAL (MG/L AS P) 0.170 0.190 0.170 0.220 0.310 0.220 MERCURY TOTAL RECOV- ERABLE (DG/L AS HO) 0.60 — — <0.10 — — TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 572 37 54 84 10 61 ARSENIC TOTAL (DG/L AS AS) <1 — — 1 — — — SELE- NIUM, TOTAL (DG/L AS SB) <1 — — <1 — — NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.430 0.470 0.650 0.330 0.530 0.270 BARIUM, TOTAL RECOV- ERABLE (DG/L AS BA) 200 — — <100 — — — SILVER, TOTAL RECOV- ERABLE (DG/L AS AG) <1 — — <1 — — NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.070 0.030 0.050 0.080 0.030 0.040 BORON, TOTAL RECOV- ERABLE (DG/L AS B) <10 — __ 30 — — — ZINC, TOTAL RECOV- ERABLE (DG/L AS ZN) 110 — — 20 — -- NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.500 0.500 0.700 0.410 0.560 0.310 CADMIUM TOTAL RECOV- ERABLE (DG/L AS CD) <1 — — <1 — — — CYANIDE TOTAL (MG/L AS CN) <0.010 — — <0.010 — — NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.110 0.080 0.100 0.130 0.060 0.110 CHRO- MIUM, TOTAL RECOV- ERABLE (DG/L AS CR) 3 — — 2 — — — PHENOLS TOTAL (DG/L) 5 — __ <1 — — NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.59 0.32 0.20 0.37 2.2 1.5 COPPER, TOTAL RECOV- ERABLE (DQ/L AS CD) 60 — — 10 — — — MBTHY- LBNB BLUE ACTIVE SUB- STANCE (MG/L) <0.01 — — 0.04 — — 212 Mo QRAuuB DB LOIZA BASIN 50055000 RIO GRANDB DB LOIZA AT CAGDAS, PR—Continued WATER-QUALITY RECORDS PERIOD OF RBCORD.—Water years 1959 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGEi October 1983 to September 1991. INSTRUMENTATION.— USD-49 and automatic sediment sampler. in, 14,500 mg/L Nov 27, 1987; Minimum daily mean, 11 mg/L EXTREMES FOR PERIOD OF DAILY RBCORD.— SEDIMENT CONCENTRATION: Maximum daily August 12, 1985. SEDIMENT LOADS: Maximum daily mean, 227,000 tons (205,890 tonnes) Nov 27, 1987; Minimum daily mean, 1.1 tons (1.0) August 13, 1991. EXTREMES FOR CURRENT YEAR.— SEDIMENT CONCENTRATION i Maximum daily mean, 1,650 mg/L October 21,1990 ; minimum daily mean, 8 mg/L February 27, 1991. SEDIMENT LOADS: Maximum daily mean, 25,500 tons (23,100 tonnes) October 21, 1990 ; minimum daily 1.1 ton (1.0 tonnes) August 13, 1991. HATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 01... DEC 11... FBB 1991 14... APR 11... JUN 25... AUG 22... DATE NOV 1990 01... DBG 11... FBB 1991 14... APR 11... JUN 25... AUG 22... TIME 0945 0920 0910 0845 1015 0910 HARD- NESS TOTAL (MG/L AS CAC03) 68 — — 75 — 65 DIS- CHARGE, INST. CUBIC FEET PER SECOND 217 80 138 192 30 75 HARD- NESS NONCARB WH WAT TOT PLD MG/L AS CACO3 0 -- -- -- -- 1 SPE- CIFIC CON- DUCT- ANCE (US /CM) 216 258 187 250 273 223 CALCIUM DIS- SOLVED (MG/L AS CA) 18 — — 19 — 16 PH (STAND- ARD UNITS) 7.6 7.4 7.4 7.3 7.7 7.3 MAGNE- SIUM, DIS- SOLVED (MG/L AS MO) 5.7 — __ 6.8 -- 6.1 TEMPER- ATURE WATER (DBG C) 26.0 23.5 23.0 24.5 29.5 28.5 SODIUM, DIS- SOLVED (MG/L AS NA) 19 — — 22 — 20 TUR- BID- ITY (NTU) 360 19 51 54 10 40 SODIUM AD- SORP- TION RATIO 1 -- -- 1 -- 1 OXYGEN, DIS- SOLVED (MG/L) 7.3 7.7 8.0 7.0 7.0 8.5 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 1.9 — — 1.9 — 2.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 89 90 93 84 91 110 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CACO3 69 86 59 80 90 79 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 22 10 21 19 15 19 SULFIDB TOTAL (MG/L AS S) <0.5 — — <0.5 — — COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 25000 K27 4300 27000 490 K9100 SULFATB DIS- SOLVED (MG/L AS 804) 13 -- -- 13 -- 11 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 4700 K170 720 3900 K20 700 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 21 — — 20 — 18 non-ideal count RIO GRANDS DB LOIZA BASIN 50055000 RIO GRANDE DB LOIZA AT CAODAS, PR—Continued MATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 213 SOLIDS, RESIDUE FLUO- SILICA, SDK OF SOLIDS, TOTAL NITRO- NITRO- NITRO- HITRO- NITRO- DATE NOV 1990 01.. . DBG 11... FBB 1991 14... APR 11... JUN 25... ADO 22... DATE NOV 1990 01... DEC 11... FBB 1991 14... APR 11... JUN 25... ADO 22... DATE NOV 1990 01... DEC 11... FBB 1991 14... APR 11... JUN 25... AUG 22... RIDE, DIS- SOLVED (MG/L AS F) <0.10 __ __ <0.10 -- 0.10 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.70 0.40 0.30 0.50 2.3 1.6 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 26000 -- __ 3500 __ -- DIS- SOLVED (MG/L AS SIO2) 31 -- -- 30 -- 31 NITRO- GEN, TOTAL (MG/L AS N) 1.2 0.90 1.0 0.91 2.9 1.9 LEAD, TOTAL RECOV- ERABLE (DG/L AS PB) 9 — — 2 — — CONSTI- TUENTS, DIS- SOLVED (MG/L) 151 -- -- 161 -- 152 NITRO- GEN, TOTAL (MG/L AS NO3) 5.3 4.0 4.4 4.0 13 8.5 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 1700 __ __ 310 -- -- DIS- SOLVED (TONS PER DAY) 88.5 -- — 83.0 — 30.8 PHOS- PHORUS TOTAL (MG/L AS P) 0.170 0.190 0.170 0.220 0.310 0.220 MERCURY TOTAL RECOV- ERABLE (UG/L AS HO) 0.60 — — <0.10 J.- — AT 105 DBG. C, SUS- PENDED (MG/L) 572 37 54 84 10 61 ARSENIC TOTAL (UG/L AS AS) <1 — -_ 1 — — — SELE- NIUM, TOTAL (UG/L AS SB) <1 — __ <1 — — GEN, NITRATE TOTAL (MG/L AS N) 0.430 0.470 0.650 0.330 0.530 0.270 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 — -- <100 — — - SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 — — <1 -- -- GEN, NITRITE TOTAL (MG/L AS N) 0.070 0.030 0.050 0.080 0.030 0.040 BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 — — 30 -- — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 110 — — 20 — — GEN, NO2+NO3 TOTAL (MG/L AS N) 0.500 0.500 0.700 0.410 0.560 0.310 CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 -- — <1 — — — CYANIDE TOTAL (MG/L AS CN) <0.010 — — <0.010 — — GEN, AMMONIA TOTAL (MG/L AS N) 0.110 0.080 0.100 0.130 0.060 0.110 CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 3 — -- 2 -- — — PHENOLS TOTAL (UG/L) 5 -- -- <1 -- -- GEN, ORGANIC TOTAL (MG/L AS N) 0.59, 0.32 0.20 0.37 2.2 1.5 COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 60 — -- 10 -- — — MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) <0.01 — -- 0.04 — — 214 RIO GRANDS DB LOIZA BASIN 50055000 RIO QRANDB DB LOI2A AT CAGUAS, PR—Continued SBDINBNT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 119 75 75 91 68 65 •128 64 •144 •326 169 93 192 161 •479 •1400 397 679 843 508 3580 500 276 •1000 •1700 •1500 •750 •700 •700 •750 •300 99 64 66 103 90 76 •104 64 •109 •318 153 97 88 79 •305 •924 229 478 443 256 1650 272 188 •540 •1120 •943 •424 •400 •400 •424 •200 35 13 14 27 16 13 •68 12 •87 •291 80 25 46 53 •666 •8730 283 2850 2150 508 25500 388 144 •1460 •5140 •3820 •859 •756 •756 •859 •162 •200 185 164 399 460 287 192 180 156 144 136 128 122 117 113 115 115 105 102 102 97 112 100 89 83 91 122 137 93 187 NOVEMBER •147 285 265 368 329 361 288 238 195 170 138 113 95 85 73 62 55 51 50 47 44 36 31 30 27 28 100 110 80 139 TOTAL 17832 55811 4633 •79 138 119 624 500 302 161 122 86 68 49 39 32 28 22 19 17 14 14 13 12 11 8.4 7.1 6.1 7.3 34 42 20 81 2674.9 208 124 227 195 116 99 89 86 85 85 116 107 73 418 235 142 99 84 77 74 72 70 71 73 66 60 61 72 101 132 11450 147 73 117 141 67 42 40 39 37 33 58 90 63 267 172 76 33 29 24 20 20 19 18 18 12 16 37 57 80 111 •795 85 25 97 83 22 11 9.5 8.8 8.4 7.3 34 32 12 415 121 34 8.8 6.5 5.0 4.1 3.9 3.8 3.5 3.6 2.1 2.6 6.0 11 22 42 •5410 4967 6539.9 • Bstiut«d RIO GRANDB DB LOIZA BASIN 50055000 RIO GRANDB DB LOIZA AT CAOOA8, PR—Continued SEDIMENT DISCHAROB, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 215 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHAROB (CFS) MEAN CONCBN- SBDIMBNT TRATION DISCHARGE (MG/L) (TONS/DAY) JANUARY MEAN DISCHARGE (CFS) MEAN CONCBN- SBDIMBNT TRATION DISCHARGE (MG/L) (TONS/DAY) MEAN DISCHARGE (CFS) 377 207 147 126 141 208 165 164 180 150 140 124 131 117 136 128 106 97 89 85 80 76 74 73 72 74 70 69 68 68 66 256 153 46 27 65 153 118 77 129 77 51 35 29 33 44 75 83 58 40 45 58 64 61 64 60 49 41 33 34 38 39 301 92 18 9.5 34 100 53 37 70 32 20 12 11 11 17 26 23 15 9.4 10 12 13 11 12 11 9.2 7.8 6.2 6.2 6.6 7.2 89 71 77 75 182 270 165 87 76 71 221 243 383 132 102 86 75 73 141 103 123 99 77 77 76 76 65 72 FEBRUARY 41 43 43 44 118 188 130 74 64 71 153 168 207 59 44 36 31 29 108 100 99 115 81 55 30 16 8 9 MEAN CONCBN- SBDIMBNT TRATION DISCHARGE (MG/L) (TONS/DAY) MARCH 9.4 8.1 9.3 9.0 156 176 67 17 12 14 105 256 310 23 12 8.6 6.2 5.9 45 30 35 30 16 11 6.4 3.0 1.5 1.9 80 65 65 95 89 159 136 123 102 72 63 66 61 62 61 56 52 53 72 58 52 93 101 61 51 75 76 53 46 44 42 12 20 26 31 28 114 114 99 69 31 29 30 30 30 30 30 34 38 38 33 78 80 67 30 26 61 53 20 51 22 24 2.6 3.5 4.5 7.7 6.8 54 44 35 21 6.2 5.1 5.2 .8 .9 .7 .5 .9 5.6 7.3 5.0 11 23 20 5.0 3.7 16 13 2.7 6.5 2.6 2.8 TOTAL 3808 1003.1 3387 1384.3 2284 343.6 216 RIO GRANDB DB LOIZA BASIN 50055000 RIO QRANDB OB LOIZA AT CAODAS, PR—Continued 8BDIMBNT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY MEAN DISCHARGE (CFS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MO/L) (TONS/DAY) APRIL 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 42 40 42 38 36 37 35 50 62 55 55 55 47 39 36 69 42 39 40 34 31 31 30 28 25 29 27 24 22 21 1161 25 23 20 73 21 27 29 42 41 42 51 88 40 41 42 59 39 40 40 41 45 39 32 36 43 26 21 20 30 40 2.9 2.4 2.3 7.4 2.1 2.8 2.8 6.1 7.9 6.9 7.6 14 5.2 4.3 4.1 12 4.6 4.1 4.3 3.7 3.8 3.3 2.6 2.7 2.9 2.0 1.5 1.3 1.6 2.3 131.5 MEAN DISCHARGE (CPS) 22 23 24 21 26 26 26 26 32 37 59 133 47 29 30 27 26 44 43 33 39 84 43 31 e463 138 64 44 39 35 33 1747 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MQ/L) (TONS/DAY) MEAN DISCHARGE (CPS) MAY MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MQ/L) (TONS/DAY) JUNE 40 65 50 30 31 38 44 51 58 60 49 107 52 48 44 42 40 40 39 35 44 72 63 26 el430 113 74 68 65 61 56 2.4 4.0 3.2 1.7 2.1 2.7 3.1 3.6 5.0 6.0 14 47 6.4 3.6 3.8 3.0 2.8 4.6 4.4 3.2 4.6 17 7.6 2.1 e5350 48 14 8.4 6.4 5.7 4.9 5595.3 34 45 35 31 45 64 65 53 41 35 42 106 72 42 39 33 28 25 25 24 29 39 33 33 29 28 22 32 28 e!040 47 37 27 21 20 88 32 30 27 24 22 83 99 79 74 71 69 74 85 85 79 66 38 18 21 21 28 33 30 e910 4.3 4.4 2.4 1.8 2.4 15 5.7 4.4 3.1 2.2 2.4 30 21 8.7 7.1 6.4 5.0 4.9 5.6 5.4 6.2 6.7 3.5 1.6 1.6 1.5 1.7 2.8 2.3 e9890 2197 10060.1 e Estimated RIO GRANDS DB LOIZA BASIN 50055000 RIO GRANDE DB LOIZA AT CAGUAS, PR—Continued SBDIMBNT DISCHARGB, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 217 MEAN DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) el610 296 137 111 84 69 60 54 51 45 44 37 36 36 166 e!480 248 110 82 89 63 52 47 61 64 44 47 44 40 55 69 CONCEN- TRATION (MG/L) JULY e986 100 108 72 54 51 53 74 37 27 23 20 20 20 98 e!040 208 40 170 20 20 21 21 39 112 58 50 51 52 64 58 TOTAL 5431 YEAR e 55562 Estimated SBDIMBNT DISCHARGB (TONS/DAY) e7050 83 47 20 13 9.4 8.5 11 4.9 3.2 3.0 1.9 1.9 1.9 159 e6450 155 13 35 4.5 3.6 3.0 2.8 7.0 19 7.4 6.5 6.1 5.4 9.9 12 14157.9 112845.9 MEAN DISCHARGB (CPS) MEAN COHCBN- SBDIMBNT TRATION DISCHARGE (MO/L) (TONS/DAY) AUGUST MEAN DISCHARGE (CPS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MO/L) (TONS/DAY) SEPTEMBER 46 39 37 35 31 34 38 29 26 25 23 23 20 25 42 29 53 107 53 36 59 235 217 73 49 38 e643 e421 122 77 64 37 34 31 28 26 23 21 21 21 20 20 21 20 20 20 20 47 96 56 40 61 164 103 38 36 34 e538 e230 88 57 51 4.5 3.5 2.9 2.7 2.1 2.2 2.1 1.6 1.4 1.4 1.2 1.3 1.1 1.4 2.4 1.6 9.3 30 8.5 3.9 11 167 92 7.5 4.9 3.6 e2850 e382 33 12 8.8 2749 3656.9 54 82 46 38 35 32 33 34 65 91 54 46 33 31 29 24 el300 227 169 106 114 e487 429 209 123 95 89 204 727 360 5366 54 75 64 61 65 70 65 55 95 155 150 149 141 122 103 88 ellSO 155 96 47 107 e316 295 170 96 50 54 156 364 148 8.1 17 8.5 6.2 5.7 5.8 5.1 5.0 19 40 22 19 12 9.8 7.5 5.7 e8740 114 57 15 34 e609 373 106 36 13 13 114 900 167 11487.4 218 RIO GRANDS DB LOIZA BASIN 50055000 RIO GRANDS DB LOIZA AT CAGRJA8, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 PARTICLB-SIZB DISTRIBUTION OP SUSPENDED SEDIMENT DATE OCT 1990 21... JUN 1991 30... AUG 27... SEP 17... DATE OCT 1990 21... JUN 1991 30... AUG 27... SEP 17... TIME 0045 1531 1759 1120 SED. SUSP. PALL DIAM. PERCENT FINER THAN .016 MM 67 82 86 92 DIS- CHARGE, INST. CUBIC FEET PER SECOND 12900 6940 2080 6480 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 82 95 95 96 SEDI- MENT, SUS- PENDED (MQ/L) 5590 8350 1820 3280 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 92 99 98 98 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 195000 156000 10200 57400 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 98 100 99 98 SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 23 27 52 40 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 100 99 99 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 37 40 60 57 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 100 100 99 98 SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 54 60 76 84 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 100 99 RIO GRANDS DE LOIZA BASIN 50055000 RIO GRANGE DE LOIZA AT CAGUAS--Continued WATBR QUALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 219 DATE OCT 1990 16... 16... 21... 21... DEC 31... FBB 1991 07... 19... APR 12... MAY 25... JON 30... JUL 01... AUQ 27... 27... SEP 17... 17... TIME 1505 1635 0115 1630 0717 0722 1305 0729 1205 2011 1535 1719 2259 1005 1550 STREAM- FLOW, INSTAN- TANEOUS (CFS) €490 4430 12100 1660 3940 200 149 57 2120 1400 2260 1800 1520 1800 1660 SEDI- MENT, SUS- PENDED (MQ/L) 3770 3100 5800 414 3400 400 500 191 8290 5610 806 945 1260 3200 1700 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) €6100 37100 189000 1850 36200 216 201 29 47400 21200 4920 4590 5170 15500 7620 SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 97 98 92 98 96 99 100 99 96 92 96 98 99 71 97 220 RIO QRANDB DB LOIEA BASIN 50055100 RIO CAODITA8 HEAR ADDAS BDBNA8, PR LOCATION.—Lat 18«14'48-, long 66«05'37-, Hydrologic Unit 21010005, on right bank 450 ft (137 m) upstream from bridge on Highway 777, 1.0 mi (1.6 km) southeast from Aguas Buenas 3.9 mi (€.3 km) northwest from Caguas and 2.1 mi (3.4 km) southwest from Las Carolina*. DRAINAOB ARBA.--5.30 mi» (13.72 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—February 1990 to current year. OAOB.—Water-stage recorder and crest-stage gage. Elevation of gage is 394 ft (120 m), from topographic map. REMARKS.—Records fair. Gage-height and precipitation satellite telmatry at station. EXTREMES FOR PERIOD OF RECORD. —Maximum discharge, 1,460 ftVs (41.3 mVs), Oct. 15, 1990, gage height, 15.24 ft (4.645 m), from rating curve extended above 100 ftVs (2.83 mVs) on basis of step-backwater analysis; minimum discharge, 1.8 ft'/s (0.051 m*/s). May 3, 6-8, 24-26, 28-30. EXTREMES FOR CURRENT YEAR.—Peak discharges greater than base discharge of 100 ftVs (2.83 mVs) and maximum (*)t Discharge Date Oct. 7 Oct. 15 Oct. 16 Oct. 18 Oct. 20 Time 1550 1600 1245 1700 2345 (ftVs) 166 *1,460 114 369 482 (mVs) 4.70 41.3 3.23 10.4 13.6 Qage height (ft) 11.11 *15.24 10.79 12.04 12.45 (») 3.386 4.645 3.289 3.670 3.795 Discharge Date Oct. Dec. Feb. July Aug. 26 31 5 16 27 Time 1630 0445 1735 0945 1645 (ftVs) 146 316 424 1,030 117 (mVi 4. 8. 12. 29. 3. '> 13 95 0 2 31 Qage height (ft) 10. 11. 12. 14. 10. 99 82 25 10 81 (m) 3.350 3.603 3.734 4.298 3.295 Minimum discharge, 2.8 ftVs (0.079 mVs), June 17-23. DISCHARGE, CUBIC FEET PBR SECOND, WATER YEAR OCTOBER 1990 TO SBPTBMBBR 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JDN JUL ADO SEP 1 3.8 2 3.3 3 3.8 4 4.1 5 3.6 6 3.6 7 11 8 4.2 9 3.5 10 11 11 5.8 12 4.2 13 5.5 14 6.6 15 100 16 30 17 13 18 77 19 32 20 36 21 109 22 19 23 11 24 17 25 25 26 47 27 20 28 12 29 9.5 30 8.5 31 7.6 TOTAL 647.6 MEAN 20.9 MAX 109 MIN 3.3 AC-FT 1280 CFSM 3 . 94 IN. 4.55 7.3 7.0 6.7 6.5 6.1 6.0 5.9 5.8 5.5 5.4 5.2 5.2 5.1 5.0 5.1 6.8 5.4 5.3 5.2 6.2 5.4 5.6 5.3 5.0 4.9 7.1 6.4 5.4 5.0 6.1 —— 172.9 5.76 7.3 4.9 343 1.09 1.21 9.5 32 5.7 5.6 5.4 7.7 3.3 13 .2 .1 7.4 10 5.6 5.5 5.5 7.5 3.2 4.2 .0 .2 29 7.8 5.6 5.5 5.5 6.2 3.2 3.4 .0 .1 9.7 6.8 5.3 5.8 5.5 5.8 3.2 3.5 .1 .1 6.2 7.4 41 6.0 5.2 5.7 3.2 3.3 .1 .0 5.4 10 14 6.1 5.2 5.7 3.6 3.3 .3 .8 5.1 7.2 7.7 5.8 5.2 7.3 3.3 3.8 .3 .9 .9 6.8 6.0 6.0 6.6 7.0 3.2 5.2 .3 .1 .9 7.3 5.5 5.8 5.8 4.1 3.1 4.1 .2 .3 .7 8.6 5.3 5.4 5.6 4.4 3.0 3.3 .4 .3 .6 7.4 5.8 5.5 5.8 4.3 3.0 3.3 .3 .2 .4 6.7 15 5.5 6.3 4.4 3.1 3.4 .4 .1 .5 6.3 9.8 5.5 7.2 3.6 3.1 3.3 .3 .1 5.0 5.9 6.6 5.5 5.9 3.5 3.0 3.4 .4 .1 6.2 5.9 6.1 5.5 5.8 3.4 2.9 9.7 .4 3.9 5.2 5.8 5.8 5.7 5.9 3.4 2.9 82 .7 3.9 .7 5.7 5.7 5.7 5.6 3.4 2.9 8.1 .9 17 .6 5.7 6.3 6.2 5.5 3.9 2.8 6.2 .0 5.4 .5 5.7 8.2 6.3 5.5 6.5 2.8 5.7 .8 5.5 .4 5.6 6.4 5.9 5.5 4.1 2.8 5.3 .8 4.5 .4 5.5 6.1 5.8 5.5 3.7 2.8 .9 5.2 4.3 .5 5.5 6.0 23 5.4 3.6 2.8 .7 8.3 5.2 .6 5.3 5.9 8.2 5.3 3.4 4.0 .6 5.5 6.7 .6 5.3 5.9 6.7 5.3 3.3 3.5 .8 4.7 4.7 .4 5.2 5.8 6.1 5.3 11 3.3 .5 4.4 4.2 4.4 5.2 5.7 5.8 5.7 4.1 3.2 .1 4.2 4.1 6.1 5.2 5.6 5.7 5.3 3.7 3.3 .1 18 5.1 5.4 5.2 5.7 5.6 5.3 3.5 3.2 .2 7.2 4.9 9.5 5.2 —— 5.5 5.5 3.3 3.3 .2 5.0 7.1 12 5.2 —— 5.5 6.1 3.3 11 .2 4.5 6.3 93 5.5 —— 5.4 —— 3.3 —— .1 4.3 287.8 222.9 224.1 198.1 169.2 148.1 102.0 225.9 159.2 150.2 9.28 7.19 8.00 6.39 5.64 4.78 3.40 7.29 5.14 5.01 93 32 41 23 7.2 11 11 82 18 17 4.4 5.2 5.3 5.4 5.2 3.3 2.8 3.3 4.0 3.8 571 442 445 393 336 294 202 448 316 298 1.75 1.36 1.51 1.21 1.06 .90 .64 1.37 .97 .94 2.02 1.56 1.57 1.39 1.19 1.04 .72 1.59 1.12 1.05 WTR YR 1991 TOTAL 2708.0 MEAN 7.42 MAX 109 MIN 2.8 AC-FT 5370 CFSM 1.40 IN. 19.01 RIO QRANDE DE LOIZA BASIN 50055100 RIO CAGOITAS NEAR AQUAS BOENAS, PR—Continued WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1989 TO CURRENT YEAR DATE TIME FEB. 19 1446 JDN. 21 1447 STREAMFLOW, INSTANTANEOUS (CFS) .60 2.87 SPECIFIC CON- DUCTANCE (UMHOS) 290 350 TEMPERA- TURE (DEO C) 21.0 24.5 DATE TIME JUL. 10 1111 AUG. 22 1143 STREAMFLOW, INSTANTANEOUS (CFS) 3.35 11.9 SPECIFIC CON- DUCTANCE (UMHOS) 340 300 221 TEMPERA- TURE (DEO C) 24.0 23.5 222 RIO ORANDB DB LOIZA BASIN 50055225 RIO CAGK7ITAS AT VILLA BLANCA AT CAGUAS, PR LOCATION.—Lat 18014'55", long 66°01'40-, Hydrologic Unit 21010005, on left bank, at C. 4 street Villa Blanca housing area at Caguas, 1.8 mi (2.9 km) upstream from Rio Grand* de Lofia, and 0.95 mi (1.53 km) northeast from Caguas Plan DRAINAGB AREA.--11.71 mi* (30.33 km*). WATBR-DISCHARQB RECORDS PERIOD OF RECORD.—December 1990 to September 1991. QAOB.—Water-stage recorder. Elevation of gage is 164 ft (50 m), from topographic map. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. EXTREMES FOR CURRENT PERIOD.--Peak discharges greater than base discharge of 1,000 fts/s (28.3 m*/s) and maximum (*)» Discharge Gage height Discharge Gage height Date Time (fts/s) (mVs) (ft) (m) Date Time (ftVs) (mVs) (ft) (m) Dec. 31 0700 1,380 39.1 12.02 3.664 Sept. 17 0940 1,090 30.9 11.43 3.484 July 16 1150 *2,060 58.3 *13.16 4.011 Minimum daily discharge, 5.6 ft'/s (0.158 m'/s), June 29. DISCHARGE, CUBIC FEET PER SECOND, WATER TEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SBP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. e Estimated 97 37 26 22 23 29 23 23 20 25 22 19 16 15 16 16 15 14 15 14 16 12 13 13 13 13 13 16 12 39 12 46 12 357 13 629 20.3 97 12 1250 1.73 2.00 14 13 14 14 119 45 30 18 15 14 28 50 39 24 21 16 14 22 35 20 17 13 13 12 13 10 9.8 13 —— 665.8 23.8 119 9.8 1320 2.03 2.12 12 10 13 16 19 25 14 15 13 10 11 11 11 13 12 9.8 8.9 14 11 11 11 73 32 16 14 17 12 11 10 10 10 475.7 15.3 73 8.9 944 1.31 1.51 10 10 11 12 13 13 13 38 16 11 13 23 21 12 14 12 9.8 9.5 9.5 9.8 11 10 9.0 8.9 9.3 8.9 8.6 8.1 7.9 8.5 —— 370.8 12.4 38 7.9 735 1.06 1.18 10 9.6 13 9.2 8.7 10 16 26 19 15 34 36 14 13 13 13 12 23 43 26 17 16 13 12 37 17 13 12 12 11 10 533.5 17.2 43 8.7 1060 1.47 1.69 11 10 9.5 10 15 15 11 10 8.5 7.4 9.5 14 7.9 7.2 7.7 7.8 6.7 6.5 6.7 6.3 6.5 6.5 13 7.8 6.3 7.6 5.8 6.7 5.6 61—— 314.5 10.5 61 5.6 624 .90 1.00 93 16 9.0 8.1 8.1 7.6 10 12 11 7.3 6.8 6.7 6.4 6.3 55 360 30 18 19 14 10 9.3 9.1 12 8.7 6.9 6.7 6.4 e6.4 e6.4 e6.6 792.8 25.6 360 6.3 1570 2.18 2.52 e7.0 e6.4 e6.0 e5.8 e5.8 e6.0 e6.0 e6.0 e5.8 e6.0 e5.8 e6.0 e5.8 e6.0 e6.1 e6.6 e6.8 e6.2 e6.0 e6.0 e7.0 e65 e20 e9.0 e8.3 e8.0 e!26 e37 e9.2 e8.4 e8.0 428.0 13.8 126 5.8 849 1.18 1.36 e7.8 e8.0 e7.8 e7.8 e7.4 e7.1 e7.4 e7.7 e8.0 e8.1 e7.9 e7.7 e7.7 e7.8 e7.3 e7.4 e!20 e!5 e20 e!3 e!5 e25 e27 e!8 e!3 ell e!2 e21 e35 e25—— 492.9 16.4 120 7.1 978 1.40 1.57 RIO ORANDB DB LOIZA BASIN 50055225 RIO CAQOITAS AT VILLA BLANCA AT CAGUAS, PR—Continued HATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1990 TO SBPTBMBBR 1991 DATE TIME FEB. 22 1412 JUN. 25 1417 STRBAMFLOW, INSTANTANEOUS (CFS) 3.42 6.29 SPECIFIC CON- DUCTANCE (UMHOS) 304 430 TEMPERA- TURE (DBQ C) 24.5 32.0 STRBAMFLOW, DATE TIME INSTANTANEOUS (CFS) JUL. 10 1402 AUG. 13 0950 7.0 8.7 223 SPECIFIC CON- TEMPBRA- DUCTANCB (UMHOS) 435 500 TURK (DBG C) 31.5 31.0 224 uo ORANDE DE LOIZA BASIN 50055250 RIO CAGUITAS AT HIGHWAY 30 AT CAOOAS, PR WATER-QUALITY RBCORDS LOCATION.--Lat 18«15'11", long 66«01'26", at Highway 30 bridge, and 0.8 mi (1.3 km) eait of Caguai plaza. DRAINAOB AREA. —14.1 mia (36.5 In?). PERIOD OF RECORD.—Water year* 1972 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 26... DEC 10... FBB 1991 14... APR 11... JON 12... AUO 20... TIME 0800 0915 1040 1100 1120 1020 DIS- CHARGE, INST. CUBIC FEET PER SECOND 75 22 42 28 23 23 SPE- CIFIC CON- DUCT- ANCE (US/CM) 288 561 490 590 540 €53 PH (STAND- ARD UNITS) 7.5 7.3 7.3 7.4 7.3 7.5 TEMPER- ATURE HATER (DEO C) 24.5 24.0 25.0 26.0 30.0 29.0 TUR- BID- ITY (NTU) 90 15 15 3.6 3.4 5.0 OXYGEN, DIS- SOLVED (MO/L) 4.7 3.6 5.5 3.1 1.8 1.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 56 42 66 38 24 18 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MQ/L) 35 50 49 73 67 81 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 41000 2700 250000 K60000 470000 K730000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 37000 55000 28000 7800 29000 78000 DATE OCT 1990 26... DEC 10... FEB 1991 14... APR 11... JUN 12... AUO 20... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL HH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L AS CA) AS MG) AS MA) 93 0 22 9.3 14 160 1 41 13 42 150 0 39 12 50 SODIUM AD- SORP- TION (MG/L RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT FBT SULFIDE SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.6 3.7 6.3 7.5 CAC03 95 150 140 170 140 180 CHLO- SULFATE RIDE, DIS- DIS- SOLVED SOLVED (MG/L <0.5 22 <0.5 44 51 (MG/L AS S) AS S04) AS CL) 19 49 52 DATE OCT 1990 26... DEC 10... FBB 1991 14... APR 11... JUN 12... AUG 20... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.30 — — 0.10 — 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 41 — — 30 — 27 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 188 __ -- 327 — 347 SOLIDS, DIS- SOLVED (TONS PER DAY) 38.1 — — 24.7 — 21.8 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 104 6 14 14 2 7 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.630 0.530 0.670 0.420 0.270 0.110 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.170 0.170 0.130 0.170 0.140 0.070 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.800 0.700 0.800 0.590 0.410 0.180 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.900 9.10 6.20 9.40 1.70 12.0 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 1.1 0.90 3.0 2.6 9.3 5.0 non-ideal count RIO ORANDB DB LOIZA BASIN 50055250 RIO CAGUITAS AT HIGHWAY 30 AT CAOUAS, PR—Continued HATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 225 DATE OCT 1990 26... DEC 10... FBB 1991 14... APR 11... JUN 12... ADO 20... DATE OCT 1990 26... DEC 10... FBB 1991 14... APR 11... JUN 12... AUO 20... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 2.0 10 9.2 12 11 17 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 2.8 11 10 13 11 17 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 12 47 44 56 51 76 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.430 2.60 1.50 2.40 2.40 4.20 MBRCDRY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) 1 — — 2 — — SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 — ~ <100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 50 — — 100 — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 16 — — 5 — — PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) 40 — — 20 ~ ~ MBTHY- LBNB BLUE ACTIVE SOB- STANCE (MG/L) 11000 1000 10 420 230 0.10 0.20 <1 <1 <1 50 <0.010 30 <0.010 0.10 226 RIO ORAMDB DB LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR LOCATION.--Lat 18«15'32", long 66°02'24'1 , Hydrologic Onit 21010005, on left bank, in the Bairoa Housing Area, 1.6 Mi (2.6 km) northwest of Plan d« Caguas, 4.1 mi (fi.fi km) east of Plaza de Aguas Buenas, and 0.9 mi (1.4 km) northwest of Bscuela Pepita Oarriga. DRAINAQB ARBA.—5.08 mi* (13.15 km1 ). MATBR-DISCHARGE RECORDS PERIOD OF RECORD.—November 1990 to September 1991. GAGE.—Hater-stage recorder and crest-stage gage. Elevation of gage is 131 ft (40 m), from topographic map. REMARKS.—Records poor. Gage-height and precipitation satellite tele affected by domestic discharge nearby station. »try at station. Mean daily discharge EXTREMES FOR CURRENT YEAR.—Peak discharges greater than base discharge of 400 ftVs (11.3 •?/•) and maximum (*)« Date Dec. Feb. May 14 5 19 Time 0345 1830 1315 Discharge (ftVs) (mVs) 450 529 502 12.7 15.0 14.2 Gage height (ft) (m) 8.82 9.23 9.08 2.S88 2.813 2.768 Date June 30 July IS July 18 Time 1140 1145 1615 Discharge (ftVs) (mVs) 450 *742 £32 12.7 21.0 18.0 Gage height (ft) (m) 8.82 *10.24 9.75 2. £88 3.121 2.972 Minimum daily discharge, 2.6 ft'/s (0.074 mVs), June IS, 17. DISCHARGE, CUBIC FEET PER SECOND, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOW DEC JAN FBB MAR APR MAY JUN JUL AUG WTR YR 1991 TOTAL 3179.3 MEAN 8.71 MAX 191 MTN 2.6 AC-FT £310 CFSM 1.71 IN. 23.28 SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. e4.7 e4.1 e4.7 eS.O e4.5 e4.5 e!4 e5.2 e4.4 e!4 e7.2 e5.4 e7.0 e8.4 e!20 e30 el 6 e94 e40 e45 e!30 e22 e!4 e23 e36 e54 e22 e!5 e!2 elO e9.4 785.5 25.3 130 4.1 1560 4.99 5.75 e9.0 e8.6 e8.2 e8.0 e7.6 e7.2 e7.2 e7.0 e6.8 e6.6 e6.4 e6.2 efi.2 e6.0 e6.0 e22 6.4 5.7 5.8 6.0 11 7.3 5.8 6.0 5.5 S.I 8.9 5.9 6.4 8.7 —— 224.5 7.48 22 5.5 445 1.47 1.64 12 12 51 9.6 5.9 5.1 .9 .6 .5 .4 .6 .8 5.0 20 14 5.0 4.6 4.8 4.4 4.4 4.4 5.0 4.6 5.1 4.9 4.9 5.0 5.7 22 15 57 319.2 10.3 57 4.4 S3 3 2.03 2.34 35 7.4 S.O 5.1 7.9 10 S.5 S.O 17 21 8.1 7.9 S.I 5.8 fi.l 5.9 5.S 5.7 5.7 5.7 5.7 5.8 5.9 5.9 5.S 5.4 5.3 5.1 5.0 4.9 S.O 245.1 7.91 35 4.9 48S 1.5S 1.79 5.S 5.7 5.2 5.0 94 11 S.2 5.2 4.8 4.7 S.S 6.2 5.5 4.7 4.8 5.5 4.5 S.S S.7 5.0 5.2 .7 .8 .6 .8 .3 .4 .4 —— —— 240.9 8. SO 94 4.3 478 1.S9 1.7S 4.4 4.2 4.4 4.7 5.2 5.8 4.S 5.0 4.S 4.8 4.4 4.2 4.1 4.3 4.2 4.2 4.1 4.4 4.1 3.8 3.8 25 4.8 4.2 4.1 9.2 4.8 4.0 3.9 3.7 3.5 ISO. 5 5.18 25 3.5 318 1.02 1.18 3.7 3.S 3.S 3.5 3.5 3.5 3.5 7.2 4.1 3.4 3.5 S.4 5.2 3.S 3.8 3.5 3.4 3.4 3.3 3.3 3.3 3.2 3.3 3.4 3.3 3.2* 3.1 3.1 3.1 4.7 —— 112.7 3.7S 7.2 3.1 224 .74 .83 3.S 3.4 3.4 3.5 3.7 3.7 S.2 11 5.2 4.9 4.S 4.0 3.4 3.3 3.2 3.2 3.1 9.4 55 7.3 3.8 4.0 3.0 3.0 7.S 3.3 3.1 3.0 3.0 3.0 3.0 184.9 5.9S 55 3.0 3S7 1.17 1.35 3.1 3.0 2.9 3.0 3.S 4.0 4.1 3.3 3.1 3.0 3.2 3.7 2.9 2.8 2.7 2.S 2.S 2.8 3.0 2.9 3.3 3.1 S.9 3.9 3.5 3.7 3.4 3.S 3.5 34—— 131.2 4.37 34 2.S 2SO .86 .96 40 S.9 S.S 5.0 4.5 4.3 28 8.0 4.8 4.0 4.0 3.9 4.0 3.S 17 191 9.8 79 14 7.2 5.9 20 eS.S e5.2 e4.8 e4.5 e4.3 e7.0 e3.7 e3.5 e3.8 512.9 IS. 5 191 3.5 1020 3.2S 3.7S e4.2 e3.5 e3.2 e3.3 e3.5 e3.3 e3.3 e3.1 e3.3 e3.1 e3.0 e2.9 e2.8 e2.9 e2.8 e3.1 e3.2 e3.3 e3.2 e3.1 e3.1 e7.4 e5.2 e4.3 e4.0 e3.8 elS eS.4 e4.5 e4.1 e3.9 12S.8 4.09 IS 2.8 252 .81 .93 e3.7 e3.8 e3.8 e3.7 e3.S e3.4 e3.5 e3.7 e3.9 e3.8 e3.8 e3.7 e3.7 e3.7 e3.S e3.5 elS e4.8 eS.O e4.0 e3.9 e6.0 e4.S e4.2 e3.8 e3.7 e4.S e4.4 eS.4 e5.8 —— 135.1 4.50 15 3.4 2S8 .89 .99 e Estimated RIO GRANDS DB LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR—Continued HATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1990 TO SEPTEMBER 1991 DATE TIME FEB. 22 1540 OUN. 25 1237 STRBAMFLON, INSTANTANEOUS (CFS) 3.01 3.33 SPECIFIC CON- DUCTANCE (UMHOS) 384 400 TEMPERA- TURE (DBS C) 23.0 26.5 STRBAMFLON, DATE TIME INSTANTANEOUS (CFS) JUL. 10 1237 AUG. 13 1036 3.83 2.86 SPECIFIC CON- DUCTANCE (UMHOS) 395 430 227 TEMPERA- TURE (DBG C) 29.0 26.0 228 KjO ORJUJDB DB LOIZA BASIN 50055400 RIO BAIROA NEAR CAGUAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°15'28-, long CC°02'13", at bridge on Highway 1, about 2.5 mi (4.0 km) upstream from Rio Qrande de Loima, and 1.4 mi (2.3 km) north of Caguas plama. DRAINAGE ARBA.--5.4 mi2 (14.0 km2). PERIOD OF RECORD.—Water years 1958, 1962-66, 1973-74, 1979 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 26... DEC 10... FBB 1991 14... APR 19... JUN 12... ADO 22... TIKE 1005 1100 1130 1335 1240 1240 DIS- CHARGE, INST. CUBIC FEET PER SECOND 346 5.8 6.3 3.0 3.8 8.3 SPE- CIFIC CON- DUCT- ANCE (US/CM) 255 473 388 418 400 ICO PH (STAND- ARD UNITS) 7.6 7.6 7.8 7.9 7.8 7.0 TEMPER- ATURE WATER (DBG C) 24.0 23.0 24.0 27.5 28.0 25.0 TUR- BID- ITY (NTU) 180 20 4.0 1.0 2.3 1.1 OXYGEN, DIS- SOLVED (MG/L) 7.7 6.3 8.0 8.1 6.6 6.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 91 73 94 100 84 78 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 50 95 18 18 1C 17 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 21000 KCOOOOOO K8300 47000 120000 100000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 20000 430000 K1100 1900 2000 72000 DATE OCT 1990 26... DEC 10... FBB 1991 14... APR 19... JTJN 12... AUG 22... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MO) AS NA) 100 1 28 8.4 1C 160 2 38 15 24 160 0 38 15 31 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATB RIDE, DIS- TOT FBT SULFIDE DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 0.7 4.3 0.8 3.5 1 4.5 CACO3 90 150 130 137 130 54 AS S) AS 304) AS CL) <0.5 14 <0.5 15 22 20 35 34 SOLIDS, RESIDUE DATE OCT 1990 26... DEC10... FBB 1991 14... APR 19... JUN 12... AUG 22... FLUO- RIDB, DIS- SOLVED (MQ/L AS F) 0.30 -- — 0.20 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SIO2) 21 — — 29 — 31 SUM OF CONSTI- TUENTS, DIS- SOLVED (MQ/L) ICC __ — 242 _- 262 SOLIDS, DIS- SOLVED (TONS PER DAY) 155 — — 1.98 — 5.87 TOTAL AT 105 DBG. C, SUS- PENDED (MQ/L) 123 24 13 9 4 1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.930 1.C4 1.9C 1.96 1.55 0.530 NITRO- GEN, NITRITE TOTAL (MQ/L AS N) 0.070 O.OCO 0.040 0.040 0.050 0.040 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.00 1.70 2.00 2.00 l.CO 0.570 NITRO- GEN, AMMONIA TOTAL (MQ/L AS N) 0.120 4.20 0.070 0.150 0.100 0.120 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.88 5.8 0.43 0.35 0.60 0.98 non-ideal count RIO GRANDS OB LOIZA BASIN 50055400 RIO BAIROA NEAR CAGUAS, PR—Continued MATER-QUALITY DATA, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 229 DATE OCT 1990 26... DEC 10... FEB 1991 14... APR 19... JUN 12... AUG 22... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.0 10 0.50 0.50 0.70 1.1 NITRO- GEN, TOTAL (MG/L AS N) 2.0 12 2.5 • 2.5 2.3 1.7 NITRO- GEN, TOTAL (MQ/L AS N03) 8.9 52 11 11 10 7.4 PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.290 <1 2.20 0.390 0.540 2 0.500 0.570 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 — — 100 — — BORON, TOTAL RECOV- ERABLE (UG/L AS B) 30 -- -- 70 -- — CHRO- CADMIUM MIUM, TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLE (UG/L (UG/L AS CD) AS CR) <1 36 — — <1 <1 — — COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 50 — — 10 — — DATE OCT 1990 26... DEC 10... FEB 1991 14... APR 19... JUN 12... AUG 22... IRON, TOTAL RECOV- ERABLE (UQ/L AS FB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HO) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AGO ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) HBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 13000 250 440 70 <0.10 <0.10 <1 <1 <1 <1 40 <0.010 <0.010 0.10 230 RIO GRANDS DB LOI2A BASIN 50055750 RIO GURABO BELOW BL MANOO, PR LOCATION.--Lat 18°14'02", long 65«53'07", Hydrologic Unit 21010005, on left bank, 2.43 mi (3.91 km) northeast of Plaza d« Juncos, 1.3 mi (2.1 km) of Escuela La Placita and 0.35 mi (0.56 km ) of Bl Mango. DRAINAGE ARBA.--22.3 mi» (57.8 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—March 1990 to current year. GAGE.—Water-stage recorder. Elevation of gage is 230 ft (70 m), from topographic map. REMARKS.--Records fair. Gage-height and precipitation satellite telemetry at station. EXTREMES FOR PERIOD OF RECORD. - -Maximum discharge, 3,760 ftVs (106 mVs), Oct. 21, 1990, gage height, 15.90 ft (4.846 m), from rating curve extended above 1,000 ft'/s (28.3 «*/•) on basis of step-backwater analysis; minimun discharge, 1.4 ftVs (0.040 •?/•), Aug. 14, 1991. EXTREMES FOR PERIOD MARCH TO SEPTEMBER 1990 AND WATER YEAR 1991.-Peak discharges greater than base discharge of 1,000 ftVs (2«.3 m*/s) and maximum (*)« Date Time July 18,1990 1945 Oct. 21,1990 0930 Oct. 26 1300 Dec. 29 1755 Dec. 31 0515 Discharge (ftVs) •1,080 *3,760 1,460 1,950 3,400 (mVs) 30.6 106 41.3 55.2 96.3 Gage height (ft) (m) •13.45, •15.90 13.92 14.42 15.63 .100 .846 .243 .395 .764 Date Time Discharge (ftVs) (mVs) June 30,1991 1500 Aug. 17 1830 Sept.27 1555 Sept.29 1115 1,080 1,420 1,680 1,640 30.6 40.2 47.6 46.4 Gage height (ft) (m) 13.45 4.100 13.87 4.228 14.15 4.313 14.11 4.301 Minimum discharge, 2.1 ftVs (0.059 mVs), May 30, 31, 1990; 1.4 ftVs (0.040 m3/s), Aug. 14, 1991. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAILY MEAN VALUES DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 22 22 50 67 71 18 22 22 10 7.0 6.6 6.1 5.4 6.0 4.8 4.6 5.1 13 9.6 9.3 6.1 5.6 ___ —— —— 4.6 4.5 5.1 4.2 4.7 4.0 3.7 3.7 3.5 3.3 3.5 3.9 9.4 11 7.0 5.7 5.6 4.2 3.8 5.0 6.5 4.4 3.5 3.1 57 31 7.4 4.9 3.9 3.5 —— 225.6 7.52 57 3.1 447 .34 .38 3.4 3.2 3.0 2.7 2.7 2.7 2.6 2.7 2.9 17 15 5.1 4.3 14 13 7.5 5.7 6.2 4.1 3.3 3.1 2.9 2.6 2.5 2.4 2.6 2.4 2.6 2.8 2.4 2.4 149.8 4.83 17 2.4 297 .22 .25 5.0 5.6 6.1 3.7 9.7 32 8.3 4.6 3.9 3.7 5.4 4.5 3.3 32 77 63 28 30 18 69 21 10 7.7 92 120 37 15 9.5 7.4 6.1 738.5 24.6 120 3.3 1460 1.10 1.23 6.0 7.7 5.5 5.0 5.0 60 238 29 12 10 8.0 6.7 5.7 8.3 14 14 20 143 65 15 8.7 6.4 5.5 123 117 33 20 12 9.1 7.9 7.1 1027.6 33.1 238 5.0 2040 1.49 1.71 6.5 9.1 12 7.3 65 27 35 94 26 218 109 34 61 56 18 13 10 9.6 8.9 7.5 6.9 23 58 36 20 22 9.6 51 20 11 8.0 1092.4 35.2 218 6.5 2170 1.58 1.82 6.8 6.4 6.6 8.1 6.8 6.3 5.7 6.1 31 80 47 121 142 95 52 40 36 81 46 22 15 11 9.6 23 79 22 12 11 9.2 9.2 1046.8 34.9 142 5.7 2080 1.56 1.75 RIO GRANDB DB LOIZA BASIN 50055750 RIO OORABO BELOW BL MANGO, PR—Continuad DISCHARGE, CUBIC PBBT PBR SECOND, WATER YBAR OCTOBBR 1990 TO SEPTEMBER 1991 DAILY MEAN VALORS DAY OCT MOV DBG JAN PBB MAR APR MAY JUN JUL AUG 231 SBP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC- FT CFSM IN. 19 11 12 66 27 14 55 122 107 156 184 39 23 17 36 88 93 83 187 240 1180 135 93 222 336 384 209 256 228 250 119 4991 161 1180 11 9900 7.22 8.33 194 88 53 39 53 47 60 46 23 21 17 19 14 12 11 11 13 12 17 32 26 42 14 9.9 18 15 62 40 17 40___ 1065.9 35.5 194 9.9 2110 1.59 1.78 57 58 214 111 41 24 18 16 14 16 13 12 11 59 75 28 17 13 119.8 9.5 11 12 139.6 8.3 10 20 151 87 679 1828.2 59.0 679 8.3 3630 2.64 3.05 218 71 44 27 34 98 86 63 39 67 71 25 19 27 18 24 19 16 14 13 12 11 11 11 11 10 10 11 12 12 18 1122 36.2 218 10 2230 1.62 1.87 32 22 28 34 51 69 46 21 16 14 48 121 94 34 27 17 14 40 161 123 67 25 21 20 29 32 14 12 — - 1232 44.0 161 12 2440 1.97 2.06 9.5 8.0 15 33 21 142 33 52 24 12 9.9 8.9 8.3 8.4 7.6 6.8 6.1 6.9 11 8.2 6.9 41 24 10 7.7 8.6 9.0 6.1 5.8 5.5 5.5 561.7 18.1 142 5.5 1110 .81 .94 5.4 5.3 5.4 7.9 6.5 5.8 5.3 6.1 11 8.4 11 8.5 37 29 16 187.8 6.0 5.7 4.9 4.6 4.7 4.3 4.2 4.8 146.6 4.7 4.2 3.7 — - 266.8 8.89 37 3.7 529 .40 .45 3.6 3.8 3.5 3.6 5.7 4.8 5.9 24 20 9.1 6.0 34 12 10 35 21 8.4 34 48 39 24 51 23 9.4 12 13 7.4 5.5 4.7 4.1 4.0 489.5 15.8 51 3.5 971 .71 .82 5.9 12 12 5.6 7.2 7.5 9.5 8.3 17 7.4 5.4 18 14 6.8 5.8 4.4 3.7 3.4 3.6 3.9 45 36 15 15 6.1 3.9 3.9 5.3 3.8 146___ 441.4 14.7 146 3.4 876 .66 .74 325 88 25 39 15 9.1 6.8 5.7 5.2 4.7 4.0 3.7 3.3 3.1 23 147 30 10 6.5 5.3 4.5 3.8 3.6 4.0 4.3 3.2 3.1 3.0 3.0 3.3 3.6 798.8 25.8 325 3.0 1580 1.16 1.33 2.5 2.3 2.1 2.1 2.2 2.1 2.3 1.9 1.8 1.7 1.6 1.5 1.5 1.7 2.3 1.9 148 63 12 64 42 78 62 18 9.5 6.5 166 237 62 24 32 1055.5 34.0 237 1.5 2090 1.53 1.76 14 9.7 7.4 6.0 5.0 4.7 5.9 56 94 43 18 11 7.4 6.0 4.8 4.3 34 20 7.4 5.3 5.4 77 72 17 9.0 10 178 101 400 108 1341.3 44.7 400 4.3 2660 2.00 2.24 WTR YR 1991 TOTAL 15194.1 MEAN 41.6 MAX 1180 MIN 1.5 AC-FT 30140 CFSM 1.87 IN. 25.35 HATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBBR 1990 TO SEPTEMBER 1991 STRBAMFLOW, SPECIFIC CON- TBMPBRA- DATB TIME INSTANTANEOUS DUCTANCB TURB (CFS) (UMHOS) (DBG C) MAR. 21 1147 MAY 17 1308 JUN. 20 1136 6.86 8.09 3.52 350 345 410 29.0 28.5 27.5 DATE TIME JUL. 18 1045 AUG. 21 1338 SEP. 13 1046 STRBAMFLOW, INSTANTANEOUS (CFS) 10.0 30.9 7.35 SPECIFIC CON- DUCTANCE (UMHOS) 300 240 350 TEMPERA- TURE (DBG C) 27.0 26.0 28.0 232 RIO GRANDS DB LOIZA BASIN 50055750 RIO ODRABO BELOW EL MANGO, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.— Water year* 1985 to 1986 and water year 1989 to current year. PERIOD OF DAILY RECORD.— SUSPENDED-SEDIMENT DISCHARGES March 1990 to September 1991. EXTREMES FOR PERIOD OF DAILY RECORD.— SEDIMENT CONCENTRATIONi Maximum daily 4 mg/L April 7,1991. SEDIMENT LOADSi Maximum daily mean, 0.4 ton (0.3 tonne) several day*. EXTREMES FOR WATER YEARS 1990-91.— i, 1,000 mg/L Oct. 21, 1990; Minimum daily mean, 5,100 tone (4,630 tonne*) October 21, 1990; Minima daily Water Year 1990 1991 Suspended-lediment concentration (mg/L) maximum minimum 246 (Jul. 07) 1,000 (Oct. 21) 5 (few day*) 4 (few day*) Suspended-cediment discharge (tone per day) minimum 0.06 (few day*) 0.04 (several day*) 326 (Jul. 07) 5,100 (Oct. 21) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JANUARY MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MARCH 22 33 2.2 22 50 67 71 18 22 22 10 7.0 6.6 6.1 5.4 6.0 4.8 4.6 5.1 13 9.6 9.3 6.1 5.6 33 58 67 76 30 31 34 20 17 16 15 13 14 13 12 15 23 19 18 14 13 2.3 8.9 12 17 1.5 2.9 2.4 .56 .32 .30 .24 .18 .22 .18 .15 .21 1.0 .50 .43 .24 .19 TOTAL RIO GRANDS DB LOIZA BASIN 233 50055750 RIO GDRABO BELOW EL MANGO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) (MQ/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 4.6 4.5 5.1 4.2 4.7 4.0 3.7 3.7 3.5 3.3 3.5 3.9 9.4 11 7.0 5.7 5.6 4.2 3.8 5.0 6.5 4.4 3.5 3.1 57 31 7.4 4.9 3.9 3.5 —— APRIL 12 11 11 11 11 11 10 10 9 9 9 10 18 20 16 9 8 8 8 9 9 9 8 11 63 57 28 20 20 20 —— MEAN DISCHARGE (CFS) MAY .16 .14 .15 .12 .13 .12 .10 .09 .08 .08 .09 .12 .59 .64 .31 .13 .12 .09 .08 .12 .15 .10 .08 .10 47 5.6 .59 .26 .22 .19 —— 3.4 3.2 3.0 2.7 2.7 2.7 2.6 2.7 2.9 17 15 5.1 4.3 14 13 7.5 5.7 6.2 4.1 3.3 3.1 2.9 2.6 2.5 2.4 2.6 2.4 2.6 2.8 2.4 2.4 20 20 23 28 30 28 23 15 10 27 26 14 10 23 23 13 11 14 10 13 18 21 25 29 31 32 30 26 20 15 11 .19 .18 .18 .20 .23 .21 .16 .12 .09 1.5 1.3 .19 .12 1.2 .85 .28 .18 .25 .11 .11 .15 .17 .19 .20 .21 .21 .20 .18 .14 .10 .08 5.0 5.6 6.1 3.7 9.7 32 8.3 4.6 3.9 3.7 5.4 4.5 3.3 32 77 63 28 30 18 69 21 10 7.7 92 120 37 15 9.5 7.4 6.1 —— MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 5.0 5.6 6.1 3.7 9.7 32 8.3 4.6 3.9 3.7 5.4 4.5 3.3 32 77 63 28 30 18 69 21 10 7.7 92 120 37 15 9.5 7.4 6.1 14 18 19 17 18 43 18 12 11 11 10 10 10 38 85 72 40 52 51 81 26 17 13 103 128 34 22 20 19 15 .20 .26 .31 .17 1.0 4.3 .43 .16 .12 .11 .14 .12 .09 16 26 17 3.6 4.0 2.3 23 1.8 .47 .26 94 52 3.7 .91 .50 .37 .23 TOTAL 225.6 57.75 149.8 9.48 738.5 253.55 234 RIO GRANDS E« LOIZA BASIN 50055750 RIO GORABO BELOW BL MANGO, PR--Continued SEDIMENT DISCHARQB, SUSPENDED (TONS/DAY), WATER YBAR OCTOBER 1989 TO SEPTEMBER 1990 JAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARQB (CFS) 6.0 7.7 5.5 5.0 5.0 60 238 29 12 10 8.0 6.7 5.7 8.3 14 14 20 143 65 15 8.7 6.4 5.5 123 117 33 20 12 9.1 7.9 7.1 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (Ma/L) (TONS/DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MO/D (TONS/DAY) JULY 11 10 7 5 5 65 246 29 20 20 19 17 13 16 24 26 30 162 72 26 18 14 12 137 85 27 20 17 14 14 14 AUGUST SEPTEMBER .18 .20 .10 .06 .06 16 326 2.6 .68 .54 .42 .30 .20 .39 1.0 1.1 2.8 214 18 1.1 .43 .26 .18 174 34 2.7 1.1 .55 .35 .30 .27 6.5 9.1 12 7.3 65 27 35 94 26 218 109 34 61 56 18 13 10 9.6 8.9 7.5 6.9 23 58 36 20 22 9.6 51 20 11 8.0 14 19 18 13 71 39 44 112 38 239 115 42 72 77 35 25 20 20 17 12 13 32 69 59 35 34 19 58 34 21 17 .25 .52 .69 .26 40 3.4 7.4 34 2.9 237 41 3.9 26 14 1.9 .89 .56 .53 .43 .25 .26 2.6 22 7.3 2.0 2.3 .50 22 2.3 .61 .38 6.8 6.4 6.6 8.1 6.8 6.3 5.7 6.1 31 80 47 121 142 95 52 40 36 81 46 22 15 11 9.6 23 79 22 12 11 9.2 9.2 13 10 10 8 7 6 6 7 35 86 57 134 142 101 76 52 52 90 56 42 23 20 19 31 93 32 29 33 35 33 .23 .17 .17 .18 .12 .10 .09 .11 14 31 11 99 60 35 13 6.2 5.4 40 8.2 2.6 .94 .58 .50 3.7 42 2.3 .91 .94 .87 .80 TOTAL 1027.6 799.87 1092.4 478.13 1046.8 380.11 RIO GRANDS DB LOIZA BASIN 235 50055750 RIO GORABO BELOW BL MANQO, PR--Continued SEDIMENT DISCHARGE, SUSPBNDBD (TONS/DAY), WATER YBAR OCTOBBR 1990 TO SEPTEMBER 1991 DAY MEAN DISCHARGE (CPS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT MEAN DISCHARGE TRATION DISCHARGE DISCHARGE (CPS) (MG/L) (TONS/DAY) (CPS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MO/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 19 11 12 66 27 14 55 122 107 156 184 39 23 17 36 88 93 83 187 240 1180 135 93 222 336 384 209 256 228 250 119 OCTOBBR 33 29 26 71 39 26 65 129 122 160 167 43 37 32 45 113 101 93 198 276 1000 137 98 258 363 410 195 268 241 261 104 1.7 .85 1.0 17 3.2 1.1 34 73 143 80 133 4.7 2.3 1.5 7.3 42 36 41 133 423 5100 55 34 318 424 578 131 228 169 204 35 194 88 53 39 53 47 60 46 23 21 17 19 14 12 11 11 13 12 17 32 26 42 14 9.9 18 15 62 40 17 40 NOVEMBER 204 90 59 50 61 55 63 61 50 49 43 36 27 20 18 17 16 15 22 43 49 62 60 53 39 27 68 59 27 48 149 22 8.5 5.3 9.9 7.5 19 8.5 3.2 2.8 2.1 1.9 1.0 .64 .52 .53 .53 .48 1.7 4.4 3.8 7.3 2.4 1.4 1.8 1.2 17 7.0 1.2 5.7 57 58 214 111 41 24 18 16 14 16 13 12 11 59 75 28 17 13 11 9.8 9.5 11 12 13 9.6 8.3 10 20 151 87 679 DECEMBER 64 66 224 106 38 27 22 20 20 19 16 16 19 65 83 40 26 18 17 16 14 12 13 16 11 10 12 32 163 93 465 12 16 216 35 4.6 1.8 1.0 .84 .77 .75 .56 .51 .60 15 25 3.2 1.3 .60 .49 .43 .35 .33 .48 .62 .28 .22 .34 1.8 324 29 1780 TOTAL 4991 8454.65 1065.9 298.30 1828.2 2473.87 236 RIO ORANDB DE LOIZA BASIN 50055750 RIO GORABO BELOW EL MANGO, PR--Continued SEDIMENT DISCHARGB, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN DISCHARGE DAY (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGB (MG/L) (TONS/DAY) JANUARY MEAN MEAN CONCBN- SEDIMENT DISCHARGB TRATION DISCHARGB (CFS) (MQ/L) (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 218 71 44 27 34 98 86 63 39 67 71 25 19 27 18 24 19 16 14 13 12 11 11 11 11 10 10 11 12 12 18 230 63 45 25 31 99 89 66 52 70 79 37 31 37 20 19 19 JL9 16 12 9 8 10 11 11 12 13 13 12 12 25 172 14 5.9 1.9 5.0 31 24 14 5.9 13 18 2.6 1.5 3.3 1.0 1.3 .98 .78 .59 .40 .29 .26 .29 .32 .32 .32 .34 .37 .39 .39 1.4 32 22 28 34 51 69 46 21 16 14 48 121 94 34 27 17 14 40 161 123 67 25 21 20 29 32 14 12 FEBRUARY 32 33 38 46 59 72 56 25 13 11 52 124 97 42 34 29 24 52 153 108 32 25 22 21 39 38 22 21 MARCH 3.8 1.9 2.9 4.8 9.5 18 8.1 1.5 .55 .46 8.2 61 30 4.1 2.6 1.3 .86 28 88 41 6.1 1.8 1.2 1.1 3.3 3.8 .90 .65 9.5 8.0 15 33 21 142 33 52 24 12 9.9 8.9 8.3 8.4 7.6 6.8 6.1 6.9 11 8.2 6.9 41 24 10 7.7 8.6 9.0 6.1 5.8 5.5 5.5 19 15 20 41 28 150 44 63 50 16 11 10 9 10 10 10 10 10 10 10 10 43 32 21 20 18 18 12 11 10 9 .50 .33 1.6 5.1 2.0 86 4.4 13 3.9 .60 .29 .23 .20 .21 .21 .19 .17 .19 .30 .25 .19 8.4 2.6 .56 .41 .44 .49 .19 .17 .15 .12 TOTAL 1122 321.84 1232 335.42 561.7 133.39 RIO GRANDB DB LOIZA BASIN 237 50055750 RIO GtJRABO BELOW BL MANGO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 5.4 5.3 5.4 7.9 6.5 5.8 5.3 6.1 11 8.4 11 8.5 37 29 16 18 7.8 6.0 5.7 4.9 .6 .7 .3 .2 .8 1 .6 .7 .2 3.7 APRIL 7 6 6 7 9 7 4 4 10 9 10 10 48 35 28 29 20 19 15 11 10 10 10 10 10 21 20 19 17 14 —— .11 .09 .09 .16 .15 .11 .06 .07 .31 .21 .30 .24 7.2 3.8 1.3 1.5 .44 .31 .22 .13 .12 .12 .11 .11 .13 .87 .36 .22 .20 .13 —— MEAN DISCHARGE (CPS) 3.6 3.8 3.5 3.6 5.7 4.8 5.9 24 20 9.1 6.0 34 12 10 35 21 8.4 34 48 39 24 51 23 9.4 12 13 7.4 5.5 4.7 4.1 4.0 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MAY 12 11 11 10 10 10 10 32 21 14 12 41 19 10 44 28 12 39 56 38 32 53 33 20 24 23 16 13 12 12 11 .11 .12 .10 .10 .15 .12 .15 3.4 1.3 .37 .20 6.1 .73 .27 5.1 1.8 .26 13 10 5.6 2.2 10 2.5 .51 .87 .89 .33 .19 .15 .13 .12 MEAN DISCHARGE (CPS) 5.9 12 12 5.6 7.2 7.5 9.5 8.3 17 7.4 5.4 18 14 6.8 5.8 4.4 3.7 3.4 3.6 3.9 45 36 15 15 6.1 3.9 3.9 5.3 3.8 146 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 13 22 23 15 15 14 13 11 26 13 11 29 26 16 16 18 22 27 30 16 62 51 27 23 15 18 18 17 10 149 .22 .86 .84 .22 .30 .31 .33 .25 1.3 .26 .16 1.5 1.1 .29 .23 .20 .21 .25 .28 .17 21 6.8 1.3 1.0 .23 .20 .18 .24 .11 215 TOTAL 266.8 19.17 489.5 66.87 441.4 255.34 238 RIO GRANDS DB LOIZA BASIN 50055750 RIO GURABO BELOW BL MANGO, PR--Continued SEDIMENT DISCHARGB, SUSPENDED (TONS/DAY), HATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DAY MEAN MEAN CONCBN- SEDIMENT DISCHARGB TRATION DISCHARGB (CFS) (MG/L) (TONS/DAY) JULY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 325 88 25 39 15 9.1 6.8 5.7 5.2 4.7 4.0 3.7 3.3 3.1 23 147 30 10 6.5 5.3 4.5 3.8 3.6 4.0 4.3 3.2 3.1 3.0 3.0 3.3 3.6 319 100 27 48 19 11 10 10 10 10 9 8 8 8 29 152 41 21 17 17 19 21 24 27 25 20 17 15 15 14 12 358 25 2.0 5.6 .87 .28 .17 .15 .14 .12 .10 .09 .07 .06 8.9 72 4.1 .59 .31 .24 .23 .22 .23 .30 .30 .17 .14 .13 .13 .13 .12 MEAN MEAN CONCBN- SEDIMENT DISCHARGB TRATION DISCHARGB (CFS) (MG/L) (TONS/DAY) MEAN DISCHARGB (CFS) AUGUST I 2.5 2.3 2.1 2.1 2.2 2.1 2.3 1.9 1.8 1.7 1.6 1.5 1.5 1.7 2.3 1.9 148 63 12 64 42 78 62 18 9.5 6.5 166 237 62 24 32 11 10 10 12 15 17 18 16 15 13 10 10 10 10 10 10 233 70 22 75 83 131 115 73 65 49 160 213 57 37 45 .07 .06 .06 .07 .08 .09 .11 .08 .08 .05 .04 .04 .04 .06 .06 .06 379 15 .77 45 11 40 22 3.7 1.7 .89 152 185 10 2.5 4.5 14 9.7 7.4 6.0 5.0 4.7 5.9 56 94 43 18 11 7.4 6.0 4.8 4.3 34 20 7.4 5.3 5.4 77 72 17 9.0 10 178 101 400 108 MEAN CONCBN- SEDIMENT TRATION DISCHARGB (MG/L) (TONS/DAY) 14 9.7 7.4 6.0 5.0 4.7 5.9 56 94 43 18 11 7.4 6.0 4.8 4.3 34 20 7.4 5.3 5.4 77 72 17 9.0 10 178 101 400 108 22 14 12 11 10 10 12 88 101 53 32 31 28 19 12 11 26 27 20 20 20 89 79 28 20 17 197 104 335 110 .88 .38 .24 .17 .13 .12 .30 35 30 7.4 1.5 .94 .56 .32 .15 .12 3.5 1.7 .39 .29 .27 35 19 1.4 .51 .47 401 36 560 38 TOTAL YBAR 798.8 15194.1 480.89 14889.59 1055.5 874.11 1341.3 1175.74 RIO ORANDE DE LOIZA BASIN 50055750 RIO OURABO BELOW EL MANGO, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 239 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE TIME DIS- CHARGE, INST. CUBIC FEET PER SECOND SEDI- MENT, SUS- PENDED (MQ/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM JUN 1991 30... 1424 AUQ 17... 1815 27... 2021 SEP 22... 1338 246 1400 595 235 1250 1760 662 460 830 6650 1060 292 18 32 38 39 50 45 20 54 64 47 35 DATE JUNE 1991 30... AUQ 17... 27... SEP 22... SBD. SUSP. FALL DIAM. PERCENT FINER THAN 016 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 64 73 56 43 74 84 67 60 89 96 96 92 95 98 97 95 98 99 98 96 99 100 99 98 100 100 100 99 240 RIO GRANDS DB LOIZA BASIN 50055750 RIO ODRABO BBLOW EL MANGO--Continued WATER QUALITY DATA, WATER YBAR OCTOBER 1989 TO SEPTEMBER 1990 SILT AND CLAY PERCENT OF SUSPENDED SBDIMBNT DATE APR 1990 02... JUN 16... JUL 07... 07... 07... 19... TIME 1306 1025 1615 1630 1645 0917 STREAM- PLOW, INSTAN- TANEOUS (CFS) SBDI- MBNT, SUS- PENDED (MQ/L) SBDI- MBNT, DIS- CHARGE, SUS- PENDED (T/DAY) SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 3.4 US 122 120 116 63 10 141 93 92 97 75 0.09 45 31 30 30 13 94 99 93 84 93 96 RIO ORANDB DB LOIZA BASIN 241 50055750 RIO GDRABO BELOW BL MANOO--Continued WATER QUALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE MAY 1991 18... 18... OUN 21... 21... 30... 30... JUL 01... 01... 01... AUQ 17... 17... SEP 08... 08... 22... TIME 2124 2209 1841 2031 1434 1809 1753 1909 2214 1740 1930 2026 2241 1253 STREAM- FLOW, INSTAN- TANEOUS (CFS) 184 486 219 162 824 290 308 252 191 371 830 280 191 252 SEDI- MENT, SUS- PENDED (MG/L) 176 190 370 181 1180 275 256 230 168 1730 603 357 351 280 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 87 249 219 79 2620 215 212 156 87 1730 1350 270 181 190 BED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 92 91 93 99 96 90 98 96 95 69 98 92 98 93 22... 1513 184 194 96 95 242 RIO GRANDE DB LOIZA BASIN 50056400 RIO VALENCIANO HEAR JUNCO8, PR LOCATION.--Lat 18«12'58", long 65«55'34", Hydrologio Unit 21010005, on left bank at Highway 919, 0.5 mi (0.8 km) upstream from Quebrada Don Victor, 1.7 mi (2.7 km) upstream from Rio Qurabo and 1.0 mi (l.C km) south of Juncos. DRAINAGE AREA.--16.4 at* (42.5 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RBCORD.—January 1971 to current year. GAGB.—Water-stage recorder. Elevation of gage Is 320 ft (98 m), from topographic map. REMARKS.—Records fair except those for estimated dally discharges, which are poor. Minor diversion from public water supply tank, 0.5 mi upstream, during low flow. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.—20 years (1972-91), 51.2 ft'/i (1.450 m>/s), 42.40 in/yr (1,077 mm/yr), 37,090 acre-ft/yr (45.7 hmVyr)* median of yearly mean discharges, 51 ftVs (1.44 ma/s), 36,900 acre-ft/yr (45 hmVyr). EXTREMES POR PERIOD OP RBCORD.--Maximum discharge, 40,000 ft'/s (1,130 mVs), Dec. 8, 1987, gage height, 25.63 ft (7.812 m), from floodmark and rating curve extended above 100 ft'/s (2.83 mVs) on basis of slope-area measurement and step-backwater analysis; minimum discharge, 1.4 ftVs (0.040 mVs), Apr. 21, 1988, result of diversion and June 12, 1990. EXTREMES OUTSIDE PERIOD OP RBCORD.—Approximate discharges (no stages were recorded) of major floods are as follows: Sept. 6, 1960, 37,100 ftVs (1,050 mVs)j Oct. 9, 1970, 18,200 ft'/s (515 •?/•). EXTREMES POR CURRENT YEAR.--Peak discharges greater than base discharge of 3,400 ftVs (96.3 m*/s) and maximum (*)i Discharge (ftVs) (mVs) Gage height (ft) (m) Date Time July 1 0530 *3,610 102 *7.86 2.396 Minimum discharge, 3.1 ftVs (0.088 mVs), May 2, 3. Date Discharge Time (ftVs) (mVs) Gage height (ft) (m) No other peak greather than base discharge. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DBC JAN PEB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX HIN AC-PT CPSM IN. CAL YR WTR YR 6.7 39 8.7 7.4 7.1 6.2 7.8 6.7 6.5 222 41 13 20 11 25 122 34 74 129 207 774 66 57 388 333 271 113 127 108 88 56 3375.1 109 774 6.2 6690 6.64 7.66 1990 TOTAL 1991 TOTAL 47 36 28 27 56 37 25 22 20 19 17 17 17 16 15 15 15 15 27 15 28 29 14 13 13 14 27 24 16 39 —— 703 23.4 56 13 1390 1.43 1.59 9247.4 10378.6 34 29 33 24 17 15 13 13 13 13 18 15 12 79 23 17 15 13 12 12 12 12 12 12 11 10 11 11 20 23 402 956 30.8 402 10 1900 1.88 2.17 MEAN MEAN 44 23 20 16 27 29 36 27 20 20 17 17 17 23 21 18 17 15 14 13 13 12 12 12 11 11 11 11 11 11 14 563 18.2 44 11 1120 1.11 1.28 25.3 MAX 28.4 MAX 15 12 14 12 12 108 33 15 13 13 35 81 46 18 35 17 14 12 25 16 14 13 14 16 14 13 12 25 —— 667 23.8 108 12 1320 1.45 1.51 774 MIN 774 MIN 18 13 14 21 16 88 19 e!3 ell elO e9.4 9.8 8.9 9.5 8.8 8.0 7.3 7.8 8.8 7.4 7.2 10 9.1 7.3 6.8 6.8 7.2 6.3 5.8 5.9 5.5 386.6 12.5 88 5.5 767 .76 .88 1.8 AC-FT 3.2 AC-PT 5.7 5.8 6.3 6.3 5.3 5.5 5.2 6.1 6.6 10 7.3 8.5 6.8 6.1 6.4 9.6 5.4 6.7 5.2 4.4 .5 .8 .5 .1 .5 .1 .6 .1 .1 .2 174.7 5.82 10 4.1 347 .36 .40 18340 20590 3.9 3.2 3.5 3.7 3.7 6.5 6.0 4.4 9.1 6.2 5.2 6.2 6.4 4.5 6.5 8.0 6.2 18 9.2 7.8 19 33 9.0 6.2 36 12 7.4 6.2 5.2 4.8 5.1 272.1 8.78 36 3.2 540 .54 .62 CPSM 1.54 CPSM 1.73 12 9.7 6.3 5.4 11 11 9.3 8.2 7.1 6.0 6.9 11 8.3 6.1 5.6 4.6 4.4 5.7 7.0 5.2 9.6 16 6.8 6.3 6.1 4.6 7.9 7.6 5.1 225—— 445.8 14.9 225 4.4 884 .91 1.01 IN. 20 IN. 23 594 45 20 66 20 13 9.9 8.8 7.8 7.3 7.0 7.2 6.6 6.8 34 183 26 12 11 14 9.3 8.2 8.5 10 8.9 7.2 7.2 7.5 7.7 22 11 1206.9 38.9 594 6.6 2390 2.37 2.74 .98 .54 7.6 6.8 7.9 6.4 6.4 7.6 7.1 5.8 .9 .3 .5 .6 .2 11 7.4 5.5 55 45 9.2 9.7 11 15 13 7.2 6.1 5.9 253 132 23 13 22 722.1 23.3 253 4.2 1430 1.42 1.64 13 10 8.3 7.3 6.3 6.6 7.0 7.0 12 9.9 8.9 7.8 7.1 6.5 5.8 5.5 58 14 8.1 8.2 17 116 71 32 17 12 16 53 284 71—— 906.3 30.2 284 5.5 1800 1.84 2.06 Estimated 243 RIO GRANDS DB LOIZA BASIN 50056400 RIO VALBNCIANO NEAR JUNCOS, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR STRBAMFLOH, SPECIFIC CON- TEMPERA- STRBAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURK DATE TIME INSTANTANEOUS DUCTANCB TURB (CFS) (UMHOS) (DBG C) (CFS) (UMHOS) (DBG C) WATER QUALITY RECORDS FEB. 13 1521 3.24 208 22.5 JUL. 18 1358 12.9 260 28.0 MAR. 03 1400 7.45 230 23.0 AUG. 15 1128 7.33 290 25.5 MAY. 14 1035 4.51 270 26.0 SEP. 13 1226 6.85 290 28.0 244 RIO ORANDB DE LOIZA BASIN 50056400 RIO VALBNCIANO NEAR JUNCOS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1983 to 1986 and water year 1989 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE> October 1989 to September 1991. IN8TRUMANTATION. — Automatic sediment sampler. n, 1,600 mg/L Oct. 06, 1985; Minium daily mean. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION! Maximum daily 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 46,300 tons (42,000 tonnes) May 18, 1985; Minimum daily mean, 0.01 ton (0.01 tonne) several days. EXTREMES FOR WATER YEARS 1990-91.-- Water Suspended- sediment concentration (mg/L) Year »••»•< »• minimum 1990 290 (Aug. 10) 3 (several days) 1991 555 (Oct. 21) 2 (several days) SEDIMENT DISCHARGE, SUSPENDED DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 48 41 36 e40 e34 30 28 106 147 36 32 29 26 27 26 24 23 27 24 24 26 62 42 25 23 22 20 20 19 27 22 MEAN CONCEN- TRATION (MG/L) OCTOBER 42 35 30 e37 e34 26 24 92 127 31 27 26 23 24 23 21 20 24 21 21 23 54 36 22 20 19 17 17 16 24 19 SEDIMENT DISCHARGE (TONS/ DAY) 5.6 3.9 2.8 e5.2 e3.0 2.0 1.8 26 50 3.0 2.3 2.0 1.6 1.7 1.6 1.4 1.2 1.7 1.4 1.4 1.6 9.0 4.1 1.5 1.2 1.1 .92 .92 .82 1.7 1.1 (TONS/DAY) MEAN DISCHARGE (CFS) 26 21 19 17 50 27 20 28 41 26 20 18 18 18 17 15 15 17 17 17 15 14 14 13 13 15 14 13 13 13 —— Suspended- sediment maximum 603 (Aug. 10) 1,960 (Oct. 21) , WATER YEAR OCTOBER MEAN CONCEN- TRATION (MG/L) NOVEMBER 23 18 16 14 43 24 17 25 35 23 17 15 15 15 14 13 13 14 14 14 13 12 12 11 11 13 12 11 12 11 —— SEDIMENT DISCHARGE (TONS/DAY) 1.6 1.0 .82 .64 5.8 1.7 .92 1.9 3.9 1.6 .92 .72 .72 .72 .64 .52 .52 .64 .64 .64 .52 .46 .46 .38 .38 .52 .46 .38 .40 .39 —— 1989 TO SBPTBt MEAN DISCHARGE (CFS) 13 13 12 12 12 12 13 11 11 11 10 10 9.8 9.3 9.0 8.9 9.1 9.3 9.6 9.4 8.8 8.1 8.1 14 19 9.7 8.6 9.6 15 14 11 discharge (tons per day) ml nl •»«•• 0.02 (several days) 0.03 (several days) fflBR 1990 MEAN CONCEN- TRATION (MG/L) DECEMBER 10 10 10 10 9 9 10 8 8 8 8 8 8 8 8 7 7 7 8 8 7 6 6 12 16 8 8 8 14 12 11 SEDIMENT DISCHARGE (TONS/DAY) .36 .36 .32 .32 .30 .30 .36 .24 .25 .24 .21 .21 .21 .20 .20 .18 .16 .18 .20 .20 .17 .13 .13 .56 1.0 .22 .20 .23 .75 .51 .32 TOTAL 1116 143.56 584 30.91 340.3 9.22 e Estimated RIO GRANDB DB LOIZA BASIN 245 50056400 RIO VALBNCIANO NEAR J0NCOS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 25 34 18 11 9.6 9.1 8.3 9.8 8.6 11 11 10 14 9.9 8.7 8.9 10 9.7 10 40 17 11 10 12 13 21 17 16 13 14 14 21 31 14 9 8 8 8 7 6 7 10 9 12 8 7 7 8 7 8 34 15 9 8 8 12 18 14 14 10 10 10 1.6 3.8 .65 .28 .21 .20 .18 .18 .15 .22 .29 .24 .56 .24 .18 .18 .24 .19 .20 9.1 .82 .27 .22 .25 .58 1.1 .68 .62 .32 .37 .41 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN DISCHARGE (CFS) FEBRUARY 11 17 11 10 9.5 9.2 13 24 33 19 15 12 11 13 10 10 12 17 11 13 16 15 12 14 8.5 8.0 7.8 6.9 —— 9 14 9 8 6 6 10 19 26 15 9 8 8 8 7 7 9 14 10 11 17 13 11 9 7 7 7 6 .29 .66 .26 .20 .17 .14 .46 1.2 3.0 .80 .35 .24 .24 .28 .19 .17 .31 .73 .30 .53 .85 .57 .39 .34 .17 .17 .16 .12 7.4 7.1 6.2 6.2 5.9 6.1 6.1 5.0 6.3 6.3 6.2 9.4 11 49 e!4 •25 e!7 e9.6 •8.4 ell elO •8.6 9.6 6.8 7.4 7.1 6.9 8.6 8.4 7.0 7.8 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MARCH 7.4 7.1 6.2 6.2 5.9 6.1 6.1 5.0 6.3 6.3 6.2 9.4 11 49 •14 •25 •17 •9.6 •8.4 ell elO •8.6 9.6 6.8 7.4 7.1 6.9 8.6 8.4 7.0 7.8 6 6 5 5 5 5 5 5 5 5 5 8 10 44 •12 •22 •14 •8 •7 •8 •8 •7 8 5 5 5 5 7 7 6 6 .14 .13 .09 .08 .08 .08 .08 .06 .08 .08 .08 .20 .30 10 e.52 •2.7 .82 .21 .16 .22 .23 .18 .25 .10 .09 .10 .08 .17 .17 .11 .14 TOTAL 434.6 24.53 368.9 13.29 311.4 17.73 e Estimated 246 RIO GRANDS DB LOIZA BASIN 50056400 RIO VALENCIANO NEAR JUNCOS, PR—Continued SEDIMENT DISCHARQB, SD8PBNDBD (TONS/DAY), WATER YEAR OCTOBER 1989 TO SBPTBMBBR 1990 JAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) 5.5 5.7 20 8.9 6.0 .8 .7 .2 .3 .7 5.9 4.7 24 11 5.5 .9 .4 .1 .6 e .0 e3.5 e2.9 e2.6 e2.5 e20 26 8.4 5.7 e4.0 e3.8 —— MEAN CONCBN- BBDIMBNT TRATION DISCHARGE (MQ/L) (TONS/DAY) APRIL 4 4 16 7 5 4 3 3 3 3 4 4 21 9 4 3 3 3 3 e3 e3 «3 e3 e3 >21 23 6 5 5 5 .07 .06 1.1 .17 .07 .05 .04 .04 .04 .05 .07 .06 2.4 .33 .07 .04 .04 .03 .04 e.04 e.03 e.02 e.02 e.02 e6.0 2.5 .15 .07 e.05 e.05 TOTAL 221.3 13.72 MEAN DISCHARGE (CF8) e3.2 e3.1 e3.2 e3.0 e2.6 e2.3 e2.2 2.4 6.7 36 9.6 6.1 4.8 10 7.2 eS.l e4.0 e3.5 e3.1 e2.8 e2.6 e2.5 e2.3 2.6 2.2 3.2 3.8 3.2 5.0 2.4 5.0 155.7 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MQ/L) (TONS/DAY) MAY e5 e9 .10 .10 .12 ill e9 7 9 35 20 18 12 12 12 ill e8 «7 «7 e7 «7 e6 e6 6 6 6 7 6 6 6 7 .05 .08 .08 .08 .08 .07 .05 .05 .33 5.0 .53 .30 .14 .33 .23 .15 .09 .06 .06 .06 .04 .04 .04 .04 .04 .06 .07 .06 .09 .04 .09 8.43 MEAN DISCHARGE (CPS) 3.8 7.8 3.7 3.5 10 16 8.5 5.0 3.7 4.3 3.4 1.8 2.0 98 94 29 12 8.2 10 32 12 7.9 5.4 9.8 27 17 8.2 6.0 5.0 4.6 459.6 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MQ/L) (TONS/DAY) JUNE 8 11 9 7 10 17 11 10 10 8 7 6 5 77 83 35 11 6 6 28 11 9 6 9 24 27 7 5 5 4 .09 .22 .10 .07 .34 .85 .25 .14 .09 .09 .07 .03 .03 134 40 3.0 .36 .15 .16 3.3 .45 .20 .09 .28 2.3 1.4 .18 .10 .07 .05 188.46 a Estimated RIO QRAKDE DB LOIZA BASIN 247 50056400 RIO VALBNCIANO NEAR JDNCOS, PR—Continued SEDIMENT DISCHARGB, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAY MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGB (MG/L) (TONS/DAY) JULY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 5.4 5.0 3.8 5.4 9.4 68 65 19 11 12 9.0 8.7 6.5 6.8 21 13 11 27 27 12 8.1 6.6 5.5 120 •135 28 16 12 9.5 8.5 8.0 3 3 3 4 8 61 58 16 11 6 5 6 6 6 18 11 9 23 24 10 6 5 5 104 •117 24 14 12 9 8 5 TOTAL 703.2 YEAR e 6253.6 Estimated .05 .05 .04 .07 .22 23 16 .85 .32 .20 .13 .13 .11 .11 1.8 .44 .31 2.4 1.7 .32 .14 .08 .08 34 •43 2.0 .61 .44 .21 .18 .11 129.10 1337.21 MEAN MEAN CONCBN- SEDIMENT DISCHARGB TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 7.6 9.9 10 11 9.6 11 9.3 136 30 393 80 41 60 44 27 22 19 18 21 15 11 11 16 23 23 16 12 16 26 12 10 5 8 7 9 10 14 14 104 26 290 65 35 52 65 35 18 7 6 7 8 8 10 13 19 18 12 10 14 23 11 10 .10 .23 .18 .39 .24 .40 .34 72 2.2 603 19 3.9 10 8.3 2.6 1.1 .36 .30 .40 .32 .24 .33 .61 1.2 1.3 .52 .31 1.3 2.3 .32 .26 1150.4 734.05 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGB (CFS) (MG/L) (TONS/DAY) SEPTEMBER 9.4 8.5 9.2 16 10 8.5 7.7 9.8 9.7 24 11 11 47 27 20 17 23 24 18 11 •8.2 •8.0 e7.7 •8.2 •8.8 •9.4 9.4 8.6 9.5 8.6 10 10 10 10 9 8 8 5 9 20 9 9 41 26 24 14 22 22 16 11 ell •9 •8 •8 •8 •8 8 8 8 8 .24 .22 .24 .42 .25 .18 .16 .14 .23 1.6 .27 .27 8.7 2.5 1.6 .68 1.6 1.9 .77 .31 .24 .20 .16 .18 .20 • .20 .20 .18 .20 .17 408.2 24.21 248 RIO GRANDE DE LOIZA BASIN 50056400 RIO VALBNCIANO NEAR JUNCOS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 1 3 3 4 5 6 7 8 9 10 11 13 13 14 15 16 17 18 19 30 31 33 33 24 35 36 37 38 29 30 31 6.7 39 8.7 7.4 7.1 6.3 7.8 6.7 6.5 322 41 13 20 11 25 122 34 74 129 207 774 66 57 388 333 371 113 137 108 88 56 11 35 9 9 9 10 9 5 5 160 43 15 16 10 33 114 30 66 113 179 555 59 50 305 275 225 100 113 81 76 46 .30 7.7 .31 .18 .17 .16 .19 .10 .09 368 6.3 .54 1.3 .39 3.4 108 3.3 35 58 255 1960 12 13 1440 389 215 40 45 28 21 7.0 NOVEMBER MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 47 36 as a? 56 37 35 22 ao 19 17 17 17 16 15 15 15 15 37 15 as 39 14 13 13 14 37 34 16 39 36 34 29 27 46 33 18 10 11 11 11 10 10 10 10 10 10 10 25 10 18 26 12 10 10 12 26 32 15 33 4.8 3.4 2.1 2.5 9.9 3.6 1.3 .59 .60 .55 .48 .44 .42 .39 .38 .41 .39 .40 2.9 .41 3.2 2.5 .45 .34 .33 .50 2.5 2.3 .71 4.7 34 29 33 24 17 15 13 13 13 13 18 15 12 79 23 17 15 13 12 12 12 12 12 12 11 10 11 11 20 23 402 29 25 29 46 23 12 8 7 8 9 16 14 7 49 20 16 14 12 12 11 10 10 9 8 8 8 8 8 15 21 305 3.6 2.6 2.9 3.1 1.1 .48 .29 .25 .28 .30 1.3 .64 .23 13 1.4 .73 .53 .42 .37 .33 .32 .30 .30 .29 .25 .22 .25 .26 1.3 1.6 770 TOTAL 3375.1 5018.03 703 53.49 956 808.94 RIO GRANDB DB LOIZA BASIN 50056400 RIO VALENCIANO NEAR JONCOS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 249 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MQ/Ii) (TONS/DAY) (CFS) (MQ/Ii) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 44 23 20 16 27 29 36 27 20 20 17 17 17 23 21 18 17 15 14 13 13 12 12 12 11 11 11 11 11 11 14 39 14 11 10 21 26 31 23 20 17 14 15 17 21 19 13 12 12 11 9 8 8 8 9 8 8 8 8 8 9 13 5.2 .92 .57 .41 3.2 2.5 3.7 1.8 1.2 .84 .65 .80 .78 1.5 1.2 .62 .59 .47 .40 .32 .27 .25 .26 .29 .25 .24 .24 .24 .24 .26 .57 FEBRUARY 15 12 14 12 12 108 33 15 13 13 35 81 46 18 35 17 14 12 25 16 14 13 14 16 14 13 12 25 —— —— —— 12 6 6 6 7 89 30 14 12 11 30 68 40 16 116 19 12 10 24 20 19 14 10 10 11 11 11 22 —— .55 .21 .21 .20 .31 94 3.7 .58 .41 .39 3.7 37 7.4 .77 16 .83 .43 .36 1.9 .85 .71 .47 .34 .42 .40 .37 .34 2.5 —— MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/Ii) (TONS/DAY) MARCH 18 13 14 21 16 88 19 •13 •11 •10 •9.4 9.8 8.9 9.5 8.8 8.0 7.3 7.8 8.8 7.4 7.2 10 9.1 7.3 6.8 6.8 7.2 6.3 5.8 5.9 5.5 17 15 15 16 10 79 22 •22 •21 •20 •17 12 10 10 11 11 12 10 10 7 6 8 10 10 9 6 5 5 5 5 5 .93 .52 .60 1.0 .38 40 1.0 • .78 • .63 • .54 • .42 .32 .24 .26 .26 .24 .23 .22 .23 .15 .12 .24 .23 .19 .16 .12 .09 .08 .08 .08 .08 TOTAL 563 30.78 667 175.35 386.6 50.42 • Estimated 250 RIO GRANDS DB LOIZA BASIN 50056400 RIO VALBNCIANO NEAR JTJNCOS, PR--Continued AY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 5.7 5.8 6.3 6.3 5.3 5.5 5.2 6.1 6.6 10 7.3 8.5 6.8 6.1 6.4 9.6 5.4 6.7 5.2 4.4 .5 .8 .5 .1 .5 .1 .6 .1 .1 .2 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) APRIL 4 4 4 4 5 5 5 5 5 8 6 5 5 6 6 7 5 5 5 4 3 3 2 2 3 12 7 10 10 10 .07 .06 .07 .08 .08 .08 .08 .09 .08 .26 .14 .12 .11 .10 .12 .23 .08 .09 .08 .05 .04 .04 .03 .03 .04 .24 .10 .11 .11 .11 > (TONS/DAY) , WATER YEAR OCTOBER 1990 TO SBPT1 MEAN MEAN CONCBN- SEDIMENT MEAN DISCHARGE TRATION DISCHARGE DISCHARGE (CFS) (MG/L) (TONS/DAY) (CFS) MAY 3.9 3.2 3.5 3.7 3.7 6.5 6.0 4.4 9.1 6.2 5.2 6.2 6.4 4.5 6.5 8.0 6.2 18 9.2 7.8 19 33 9.0 6.2 36 12 7.4 6.2 5.2 4.8 5.1 10 9 6 5 5 6 9 10 10 7 8 8 10 7 5 5 5 69 10 7 19 38 23 6 32 15 14 12 11 9 7 .10 .08 .06 .04 .04 .11 .15 .12 .26 .13 .11 .13 .17 .09 .08 .11 .08 5.1 .24 .16 1.4 4.0 .64 .10 5.7 .48 .30 .19 .15 .12 .10 12 9.7 6.3 5.4 11 11 9.3 8.2 7.1 6.0 6.9 11 8.3 6.1 5.6 4.6 4.4 5.7 7.0 5.2 9.6 16 6.8 6.3 6.1 4.6 7.9 7.6 5.1 225 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 11 8 5 5 7 7 6 5 4 4 7 9 6 5 23 5 5 6 6 5 5 11 12 7 4 3 6 6 4 171 .49 .23 .10 .08 .21 .21 .14 .10 .08 .06 .14 .30 .15 .09 .33 .07 .06 .10 .13 .07 .08 .45 .21 .13 .06 .04 .18 .14 .06 382 TOTAL 174.7 2.92 272.1 20.54 445.8 386.49 251 RIO GRANDS DB LOIZA BASIN 50056400 RIO VALENCIANO NEAR JUNCOS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO 1991 DAY MEAN DISCHARGE (CPS) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 594 45 20 66 20 13 9.9 8.8 7.8 7.3 7.0 7.2 6.6 6.8 34 183 26 12 11 14 9.3 8.2 8.5 10 8.9 7.2 7.2 7.5 7.7 22 11 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JULY TOTAL YEAR 1206.9 10378.6 402 39 18 57 14 8 7 5 5 5 5 4 4 4 27 189 29 11 7 11 4 4 4 7 5 7 11 11 10 21 31 —— 1460 5.3 1.0 14 .93 .27 .18 .13 .10 .10 .10 .07 .08 .07 11 123 2.6 .36 .20 .46 .11 .08 .09 .20 .14 .14 .22 .21 .23 2.3 .93 1624.60 9267.85 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 7.6 6.8 7.9 6.4 6.4 7.6 7.1 5.8 .9 .3 .5 .6 .2 11 7.4 5.5 55 45 9.2 9.7 11 15 13 7.2 6.1 5.9 253 132 23 13 22 19 7 4 4 3 3 3 3 3 4 5 5 5 10 6 6 47 41 9 8 9 13 11 6 5 5 297 103 14 6 19 .41 .15 .09 .06 .06 .06 .06 .05 .04 .05 .06 .06 .06 .50 .13 .10 20 10 .23 .23 .30 .69 .42 .12 .08 .08 637 48 1.0 .22 1.3 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 13 10 8.3 7.3 6.3 6.6 7.0 7.0 12 9.9 8.9 7.8 7.1 6.5 5.8 5.5 58 14 8.1 8.2 17 116 71 32 17 12 16 53 284 71 1] 1 4 12! i; 4 1! 9' 61 31 1< 1, i: 4' 22; 6 I .46 } .23 > .11 .08 .07 .07 .08 .08 .32 .18 .10 .09 .08 .07 .06 1 .06 i 39 t .63 > .13 1 .16 i .73 t 50 J 18 1 3.2 1 .64 L .36 » .79 1 8.9 1 237 L 13 722.1 721.61 906.3 374.68 252 RIO ORANDB DB LOIZA BASIN 50056400 RIO VALENCIANO NEAR JUNCOS, PR--Continued MATER QUALITY DATA, WATER YEAR OCTOBER 1989 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE JUL 1990 07... 25... OCT 16... DEC 31... AUQ 1991 27... 27... 27... SEP 29... TIME 1715 1055 1545 0953 1720 1810 2050 1220 STREAM- FLOW, INSTAN- TANEOUS (CFS) 39 103 740 620 456 1360 749 786 SEDI- MENT, SUS- PENDED (MG/L) 170 103 679 453 1155 1150 502 434 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 18 28 1400 760 1420 4220 1020 920 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 94 98 97 96 97 94 88 253 RIO ORANDB DB LOIZA BASIN 50056900 QDBBRADA MAMBY NEAR OURABO, PR LOCATION.—I*t 18«14'57", long 65°56'44", Hydrologie Unit 21010005, at l«£t downstream aide of bridge on Highway 189, 1.9 ml (3.0 km) coutheact of Gurabo plaza, and 2.1 mi (3.4 km) northwest of Juncoc plaza. DRAINAGE AREA.--2.30 mi* (5.96 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—December 1983 to current year. OAOE.—Water->tage recorder and crect-ctage gage. Elevation of gage i« 180 ft (55 m), from topographic map. REMARKS.— Record* fair. AVERAGE DISCHARGE.--? yeara (1985-91), 3.58 ft'/« <0.101 mV«), 21.14 in/yr (537 mm/yr), 2,594 acre-ft/yr (3.20 hmVyr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 2,740 ft'/« (77.6 M3/*), Nov. 26, 1987, gage height, 11.04 ft (3.365 m), from rating curve extended above 400 ft'/« (11.3 •(*/•) on bail* of indirect measurement of peak flow and atep-backwater analytic; minimum discharge, 0.15 ft'/« (0.004 m'/«), June 12, July 5, 6, 1990. EXTREMES FOR CURRENT YEAR.—Peak diachargea greater than bate discharge of 500 ftV« (14.2 mVa) and maximum (*)« Date Oct. 7 Oct. 16 Time 1700 1345 Di •charge (ftVa) (mVa) *670 510 19.0 14.4 Gage height (ft) (m) *7.28 2.219 6.85 2.068 Date Oct. 24 Dec. 11 Dicebarge Time (ftVa) (mVa) 1945 1930 510 608 14.4 17.2 Gage height (ft) (m) 6.85 2.088 7.12 2.170 Minimum daily di•charge, 0.21 ft'/a (0.006 m1/*), Sept. 26. DAY OCT DISCHARGB, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 26 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR .69 .67 .98 1.4 1.0 .77 51 4.2 1.0 25 5.2 1.5 1.6 .79 33 49 12 26 15 31 83 5.1 2.5 47 48 52 7.5 3.4 2.5 2.4 2.6 518.00 16.7 63 .67 1030 7.27 8.36 1990 1991 1.9 1.7 1.6 1.6 1.9 1.4 1.3 1.3 1.3 1.4 1.2 1.2 1.1 1.1 1.0 1.1 1.1 1.1 1.1 5.0 1.6 1.1 1.0 .97 1.0 1.1 1.2 1.1 1.1 1.3 —— 41.87 1.40 5.0 .97 83 .61 .68 TOTAL 1018 TOTAL 1069 1.8 3.1 12 2.5 1.5 1.2 1.2 1.1 1.3 1.4 18 3.8 1.5 19 29 3.7 1.8 1.5 1.4 1.4 1.4 1.4 1.3 1.3 1.2 1.2 1.2 1.3 5.5 2.5 46 174.5 5.63 48 1.1 346 2.45 2.82 .08 MEAN .22 MEAN 6.0 2.0 1.3 1.2 1.1 1.2 1.1 1.1 1.0 1.0 1.0 1.2 1.0 .98 .95 .97 .97 .93 .87 .83 .83 .84 .86 .83 .87 .98 .96 .93 .93 .90 1.0 36.63 1.18 6.0 .83 73 .51 .59 2.79 MAX 2.93 MAX 1.1 1.1 1.2 1.2 1.4 1.9 1.2 1.1 1.2 1.5 2.7 1.3 1.3 .90 1.6 .90 .75 1.2 1.6 .94 .81 .73 .72 .95 .81 .75 .71 .68 —— —— —— 32.25 1.15 2.7 .68 64 .50 .52 83 MIN 83 MIN .68 .74 .82 1.1 1.5 10 1.2 .98 .91 .78 .73 .68 .66 .66 .61 .62 .53 .54 .57 .48 .48 1.1 .70 .48 .46 .68 .73 .50 .46 .48 .49 31.35 1.01 10 .46 62 .44 .51 .17 AC-FT .21 AC-FT .54 .51 .55 .54 .64 .57 .55 .84 .59 .49 .53 .53 .56 .54 .61 .68 .55 .48 .44 .38 .36 .38 .38 .35 .36 .39 .42 .42 .44 .42 —— 15.04 .50 .84 .35 30 .22 .24 2020 2120 .42 .43 .42 .42 .49 .49 .44 .50 .45 .42 38 16 1.4 .94 .79 .78 .68 .72 .72 .66 .60 1.4 .75 .58 2.0 .90 .64 .56 .57 .61 .66 74.44 2.40 38 .42 148 1.04 1.20 CFSM 1.21 CFSM 1.27 .98 1.2 .87 .79 .95 2.5 1.9 1.4 1.1 .72 .67 .76 .67 .60 .57 .51 .47 .51 .49 .50 .53 .47 .49 .43 .41 .39 .37 .38 .37 2.3 —— 24.30 .81 2.5 .37 46 .35 .39 IN. 16 IN. 17 24 1.3 .54 .49 .48 .38 .38 .40 .42 .30 .26 .28 .32 .35 2.2 12 1.4 .55 .43 .45 .41 .38 .36 1.8 .71 .34 .31 .25 .28 .28 .33 52.38 1.69 24 .25 104 .73 .85 .47 .29 .33 .30 .39 .51 .48 .29 .35 .30 .35 .38 .46 .44 .37 .65 1.2 .33 .23 .27 .28 .28 .40 1.6 .71 .26 .27 .25 10 3.6 .48 .27 .28 26.31 .85 10 .23 52 .37 .43 .32 .29 .29 .25 .23 .23 .33 .25 .28 .36 .37 .26 .24 .23 .27 .28 1.5 .99 1.9 1.1 .59 17 5.5 .84 .32 .21 .23 .43 6.1 .96 —— 42.15 1.40 17 .21 84 .61 .68 254 RIO GRANDB DB LOIZA BASIN 50056900 QUHBRADA HAMBY NEAR QDRABO, PR--Continued WATER QUALITY RECORDS PERIOD OF RBCORD.--WATER YEARS MARCH 1984 TO CURRENT YEAR DATE FEB. MAR. JUN. 02 18 27 TIMB 1237 1516 1254 STRRAMFLOW, INSTANTANEOUS (CFS) .48 .53 .42 SPECIFIC CON- DUCTANCE (UMHOS) 498 510 625 TEMPERA- TURE (DBG C) 24.0 24.5 29.0 DATE JUL. AUG. 07 15 TIMB 1118 1439 STREAMFLOW, INSTANTANEOUS (CFS) .27 .64 SPECIFIC CON- DUCTANCE (UMHOS) 600 630 TEMPERA- TURE (DEC C) 28.0 28.5 RIO GRANDS DB LOIZA BASIN 255 50057000 RIO OORABO AT ODRABO, PR LOCATION.—Lat 18«15'30", long 65»58'05-, Hydrologic Unit 21010005, on left bank, at bridge on Highway 181, 0.3 ml (0.5 km) east of Ourabo, and 4.5 mi (7.6 km) upstream from Rio Grande de Loixa. DRAINAGE AREA.--60.2 mi* (155.9 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RBCORD.—1958 (occasional low-flow measurement* only), January to September 1959 (monthly measurements only), October 1959 to current year. GAGB.—Water-stage recorder and crest-stage gage. Datum of gage is 131.58 ft (40.106 m) above mean sea level. Prior to Oct. 1, 1989 datum 5.0 ft (1.5 m) higher. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--32 years (1960-91), 135 ftVs (3.823 mVs), 30.45 in/yr (773 mm/yr), 97,810 acre-ft/yr (120 bmVyr); median of yearly mean discharges, 127 ft3/* (3.60 mVs), 92,000 acre-ft/yr (110 hmVyr). EXTREMES FOR PERIOD OF RECORD.—maximum discharge, 74,600 ftVs (2,133 mVs), Sept. 6, 1960, gage height, 27.7 ft (8.443 m), from floodmark, from rating curve extended above 8,000 ft'/s (227 m'/s) on basis of slope-area measurement at gage height 21.6 ft (6.58 m), contracted opening, culvert and flow over road measurement at gage height 23.76 ft (7.242 m), datum then in use, and estimate of peak flow based on slope-area measurements of Rio Ourabo and Rio Valenciano, 7.0 mi (11.3 km) upstream, adjusted for channel storage and flow from intervening area; minimum discharge, 4.5 ftVs (0.127 mVs), Feb. 21, 25, 1968. EXTREMES OUTSIDE PERIOD OF RBCORD.--Approximate elevation to gage datum of the Aug. 4, 1945 flood, as pointed out by local residents, 26.6 ft (8.1 m), datum then is use. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 3,000 ftVs (85.0 mVs) and maximum (*) i Discharge Gage height Discharge Gage height Date Time (ftVs) (mVs) (ft) (m) Date Time (ftVs) (mVs) (ft) (m) Oct. 21 1130 *5,010 142 *16.88 5.145 Dec. 31 0745 3,380 95.7 14.47 4.410 Oct. 24 2300 3,090 87.5 13.97 4.258 Minimum discharge, 6.9 ftVs (0.195 mVs), Aug. 13, 14. DISCHARGE, CUBIC FEET PBR SECOND, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DBC JAN FBB MAR APR MAY JUN JUL AUO SBP 1 44 2 61 3 40 4 67 5 50 6 44 7 176 8 165 9 74 10 415 11 317 12 100 13 69 14 57 15 228 16 446 17 303 18 224 19 465 20 385 21 2310 22 335 23 194 24 606 25 945 26 870 27 417 28 402 29 411 30 419 31 226 TOTAL 10865 MEAN 350 MAX 2310 MIN 40 AC-FT 21550 CFSM 5 . 82 IN. 6.71 e!30 elOO e90 elSO ellO 101 77 93 64 62 56 56 52 49 47 46 47 46 54 69 57 86 51 43 40 48 69 100 55 69 —— 2117 70.6 150 40 4200 1.17 1.31 CAL YR 1990 TOTAL 28341.7 WTR YR 1991 TOTAL 30182.1 108 88 240 153 75 57 52 49 47 47 80 89 56 183 163 79 54 48 45 43 43 42 42 44 40 37 37 45 160 173 1040 3459 112 1040 37 6860 1.85 2.14 MEAN MEAN 346 126 74 57 53 92 109 74 72 66 78 53 49 54 53 51 50 46 43 41 38 36 33 32 30 31 31 29 27 28 26 1928 62.2 346 26 3820 1.03 1.19 77.6 MAX 82.7 MAX 35 28 29 34 40 98 118 43 33 27 69 110 173 49 55 42 35 33 165 110 93 48 41 45 45 48 38 32 —— 1716 61.3 173 27 3400 1.02 1.06 2310 MIN 2310 MIN 46 29 27 49 35 213 76 60 65 39 32 30 27 27 26 24 23 25 30 29 26 37 54 31 26 42 29 25 22 21 20 1245 40.2 213 20 2470 .67 .77 9.7 AC-FT 7.5 AC-FT 20 19 18 18 19 19 17 17 19 21 26 23 32 30 24 29 20 16 16 14 14 14 14 13 12 18 18 14 12 11 —— 557 18.6 32 11 1100 .31 .34 56220 59870 10 10 9.6 9.5 11 15 16 16 32 27 132 103 39 24 31 35 25 27 61 39 43 54 51 25 39 42 24 18 15 13 11 1007 . 1 32.5 132 9.5 2000 .54 .62 CFSM 1.29 CFSM 1.37 14 26 23 16 14 27 26 23 21 19 14 20 29 19 16 13 11 10 13 11 12 66 32 27 19 14 10 15 12 238 810 27.0 238 10 1610 .45 .50 IN. IN. 845 175 64 79 51 33 27 22 20 18 16 16 14 13 17 324 91 39 26 24 19 16 14 19 21 14 13 13 13 15 29 2100 67.7 845 13 4170 1.13 1.30 17.51 18.65 14 11 11 11 9.7 9.5 11 10 9.4 8.6 8.2 8.1 7.5 13 33 12 94 218 45 53 98 79 89 36 21 16 273 525 111 52 50 1947.0 62.8 525 7.5 3860 1.04 1.20 47 38 24 19 16 14 15 24 86 64 35 26 19 16 13 12 49 65 50 37 32 173 234 77 47 37 131 171 599 261 —— 2431 81.0 599 12 4820 1.35 1.50 Estimated 256 RIO GRANDS DB LOIZA BASIN 50057000 RIO ODRABO AT GURAGO, PR—Continued WATER QUALITY RECORDS PERIOD OF RECORD.—WATER YEARS AUGUST 1981 TO CURRENT YEAR STRBAMFIiOW, SPECIFIC CON- TEMPERA- STRBAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCB TURB DATE TIKE INSTANTANEOUS DUCTANCB TORE (CFS) (DMHOS) (DBG C) (CFS) (DMHOS) (DBG C) FEB. 16 1122 11.2 304 24.5 OUL. 11 1314 16.4 365 29.5 MAR. 18 1303 4.19 310 27.0 AUG. 15 1324 26.1 320 29.5 JUN. 24 1129 14.0 300 28.0 O to 0» «J 0» M to 0t M U U UifrM *. e touM o»0» in in * MM M M M *. *. in in »> «n in in «j M -J a» M U UM U M to o o a» M M M o»o at we in UMM o M «JM Mfl» in in -o M o M M M MU a»in »• win M o in o» M in * M M-O M M U *• MM M in 0t OM M-o0fO» o»-otoe-o in»in0)» u MM ovi e M u OM a» M M M M M • M M ot o» «e -o e M in 10 o w M» U -O M u uin in «e u w u to * M M M m * o» o» M MM W* «e M in in in MM M M tnM-oa»tn mea»eto M in u u to o» «n in «o to M M 9l 0» tfl 09 0» u u m to o in we o» o» in M «J h> to W M M* MMMMM MMUUW - - - ou»»» tno»Minin MMMMM M m -o o» o» M M e M* 011 •O tOMO u»»in in MO * M M ill ro en •s 258 RIO GRANDS DB LOIZA BASIN 50057000 RIO GKJRABO AT GKJRABO--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), MATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 346 126 74 57 53 92 109 74 72 66 78 53 49 54 53 51 50 46 43 41 38 36 33 32 30 31 31 29 27 28 26 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MO/L) (TONS/DAY) MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGB (MQ/L) (TONS/DAY) MEAN DISCHARGE (CFS) JANUARY 214 94 75 40 37 62 64 53 56 37 52 35 24 25 39 29 16 14 8 8 8 10 10 13 13 17 20 21 19 15 21 221 35 15 6.3 5.5 17 20 12 12 7.1 11 5.2 3.1 4.1 5.7 4.1 2.2 1.8 .93 .88 .83 .98 .92 1.1 1.1 1.4 1.6 1.6 1.4 1.2 1.5 35 28 29 34 40 98 118 43 33 27 69 110 173 49 55 42 35 33 165 110 93 48 41 45 45 48 38 32 FEBRUARY 26 22 19 17 29 65 79 34 32 32 38 79 165 50 45 31 25 321 123 73 62 34 29 30 25 19 19 17 CONCBN- SEDIMENT TRATION DISCHARGB (MG/L) (TONS/DAY) MARCH 2.4 1.7 1.5 1.5 3.4 44 36 4.1 2.9 2.4 7.0 38 103 7.0 7.3 3.6 2.4 27 68 23 18 4.6 3.3 3.5 3.0 2.5 1.9 1.5 46 29 27 49 35 213 76 60 65 39 32 30 27 27 26 24 23 25 30 29 26 37 54 31 26 42 29 25 22 21 20 32 21 21 32 24 126 84 42 47 28 18 11 10 10 10 10 9 14 20 14 9 24 37 22 17 27 19 14 11 10 8 4.4 1.7 1.6 4.7 2.3 108 20 8.4 9.5 3.0 1.6 .85 .76 .72 .71 .65 .55 1.0 1.6 1.1 .63 2.9 5.9 1.9 1.2 5.6 1.5 .96 .61 .52 .46 TOTAL 1928 403.54 1716 424.5 1245 195.32 259 RIO ORANDE DB LOIZA BASIN 50057000 RIO OORABO AT OTRABO--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCBN- SBDIMBNT DISCHARGE TRATION DISCHARGE DAY (CPS) (MO/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 20 19 18 18 19 19 17 17 19 21 26 23 32 30 24 29 20 16 16 14 14 14 14 13 12 18 18 14 12 11 —— APRIL 8 8 10 12 12 12 11 11 12 12 13 14 21 21 20 20 22 21 20 17 13 11 11 10 8 8 9 10 12 16 MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCEN- SBDIMBNT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) (CPS) (MO/L) (TONS/DAY) MAY .42 .42 .49 .57 .63 .59 .50 .51 .59 .71 .83 .88 1.9 1.6 1.4 1.5 1.2 .90 .85 .64 .48 .40 .39 .35 .29 .44 .47 .34 .37 .47 —— 10 10 9.6 9.5 11 15 16 16 32 27 132 103 39 24 31 35 25 27 61 39 43 54 51 25 39 42 24 18 15 13 11 20 21 21 21 21 21 19 17 19 17 170 57 37 34 34 33 159 27 49 27 23 43 42 19 35 39 33 28 23 18 15 .55 .56 .54 .54 .62 .83 .83 .87 1.5 1.2 184 19 4.1 2.2 2.7 3.0 9.2 2.0 9.2 2.8 2.7 6.7 6.5 1.4 4.7 4.6 2.3 1.3 .91 .61 .46 JUNE 14 26 23 16 14 27 26 23 21 19 14 20 29 19 16 13 11 10 13 11 12 66 32 27 19 14 10 15 12 238 13 15 11 11 10 10 8 10 9 9 10 10 10 8 13 17 18 17 15 17 21 48 27 19 15 11 10 10 10 331 —— .48 1.0 .67 .46 .42 .67 .58 .58 .53 .46 .36 .54 .77 .38 .55 .56 .53 .47 .52 .50 .71 11 2.4 1.4 .82 .42 .27 .38 .31 773—— TOTAL 557 21.13 1007.1 278.42 810 801.74 260 RIO GRANDB DE LOIZA BASIN 50057000 RIO GURABO AT OURABO--Continued SBDIMBNT DISCHARGB, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGB (MQ/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 845 175 64 79 51 33 27 22 20 18 16 16 14 13 17 324 91 39 26 24 19 16 14 19 21 14 13 13 13 15 29 2100 30182.1 JULY 547 117 45 51 36 24 21 13 11 10 9 9 9 9 12 140 60 46 38 32 26 19 14 8 5 7 10 11 12 15 23 2050 69 8.4 12 5.2 2.2 1.5 .79 .57 .46 .40 .38 .34 .31 .77 145 17 4.9 2.7 2.1 1.4 .82 .50 .41 .32 .27 .33 .38 .42 .74 2.0 2331.61 30320.01 MEAN DISCHARGB (CFS) 14 11 11 11 9.7 9.5 11 10 9.4 8.6 8.2 8.1 7.5 13 33 12 94 218 45 53 98 79 89 36 21 16 273 525 111 52 50 1947.0 MEAN CONCBN- SBDIMBNT TRATTON DISCHARGE (MQ/L) (TONS/DAY) AUGUST 12 12 11 11 11 12 13 17 16 12 11 8 7 11 37 20 111 139 39 41 88 61 82 55 39 21 434 243 58 37 33 .49 .35 .34 .33 .29 .30 .40 .45 .39 .28 .23 .18 .14 .74 3.5 .69 206 123 5.1 16 27 18 22 5.6 2.3 .91 446 407 21 5.6 4.3 1318.91 MEAN DISCHARGE (CFS) 47 38 24 19 16 14 15 24 86 64 35 26 19 16 13 12 49 65 50 37 32 173 234 77 47 37 131 171 599 261 2431 MEAN CONCBN- SBDIMBNT TRATION DISCHARGB (MQ/L) (TONS/DAY) SEPTEMBER 33 34 38 31 20 13 11 17 58 47 37 26 16 11 9 7 30 53 36 31 20 315 179 114 80 47 86 114 598 124 5.1 3.6 2.5 1.6 .85 .48 .46 1.1 16 8.2 3.7 1.9 .83 .49 .31 .22 6.9 11 7.2 3.7 1.8 137 125 24 11 4.8 97 65 1260 106 1907.74 261 RIO GRANDS DE LOIZA BASIN 50057000 RIO ODRABO AT ODRABO, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1990 11... 21... 24... 26... DEC 31... 31... JUN 1991 30... ADO 17... 27... DATE OCT 1990 11... 21... 24... 26... DEC 31... 31... JUN 1991 30... ADO 17... 27... TIME 1852 1653 2032 2015 0645 0731 1752 2212 2132 SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 72 22 76 70 54 47 67 67 70 DIS- CHARGE, INST. CUBIC FEET PER SECOND 1240 1210 937 913 2870 3360 1230 807 1650 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 71 26 86 74 67 60 73 71 75 SEDI- MENT, SUS- PENDED (MG/L) 1370 1340 1100 586 3067 2380 1640 1010 751 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 90 44 95 95 79 75 95 98 96 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 4590 4380 2780 1440 23800 21600 5450 2200 3350 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 97 45 99 98 91 86 98 99 99 SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 28 17 30 27 19 24 33 47 39 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 45 100 100 99 95 99 100 100 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 44 16 50 47 30 33 49 52 48 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 100 46 100 100 100 99 100 100 100 SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 55 21 64 61 41 39 56 61 63 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 53 100 100 100 100 100 100 100 262 RIO ORANDE DB LOIZA BASIN 50057000 RIO ODRABO AT OURABO, PR--Continu«d WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM DATE OCT 1990 09... 21... 24... 24... 26... 26... 26... DEC 31... 31... 31... 31... FEB 1991 07... MAR 06... 06... APR 16... MAY 11... 11... JON 30... 30... JUIf 01... 01... 16... 16... ADO 17... 18... 27... 28... TIME 1318 1627 2132 2245 1207 1715 2000 0630 0939 1000 1150 0737 1417 1602 1715 1752 1922 1722 2307 0733 2310 1010 1240 2127 0312 1947 0132 STREAM- FLOW, INSTAN- TANEOUS (CFS) 61 1450 2320 3080 453 1570 913 2450 2550 2330 1440 124 523 454 21 462 467 877 480 2440 400 632 523 622 422 521 907 SEDI- MENT, SUS- PENDED (MQ/L) 1230 489 2220 1200 206 398 651 1650 1660 485 664 SBDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 202 1920 13900 9980 252 1690 1600 10900 11400 3050 2580 304 265 240 160 1310 1920 1490 581 3930 162 278 192 463 221 255 332 102 374 294 1630 2420 3530 753 25900 175 474 271 777 252 359 813 100 92 87 94 93 94 95 71 96 90 89 97 93 97 95 99 98 93 99 42 98 86 87 88 100 90 97 263 RIO ORANDB DE LOIZA BASIN 50057025 RIO GURABO NEAR GURABO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°15'56", long 65°59'04", at bridge on Highway 941, 1.2 mi (1.9 k») west-northwest fi station 50057000, and 1.0 Mi (1.6 km) northwest of Ourabo plaza. DRAINAOB AREA.--62.8 mi* (162.7 lot). PERIOD OF RECORD.—Water years 1979 to current year. HATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 gaging DATB OCT 1990 24... DEC 10... FBB 1991 28... APR 23... JUN 12... AUG 20... TIME 1250 0750 0825 1350 0955 0900 DIS- CHARGE, INST. CUBIC FEET PER SECOND 25 42 — -- — — SPE- CIFIC CON- DUCT- ANCE (US/CM) 255 392 382 360 428 300 PH (STAND- ARD UNITS) 7.4 7.2 7.3 7.0 7.2 7.3 TEMPER- ATURE HATER (DBG C) 26.0 23.5 26.0 31.5 29.5 28.0 TUR- BID- ITY (NTU) 65 12 14 5.0 18 17 OXYGEN, DIS- SOLVED (MG/L) 6.3 3.1 4.1 3.2 1.2 1.3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 77 36 50 42 16 17 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 33 21 16 21 22 29 COLI- FORM, FECAL, 0.45 UM-MF (COLS. / 100 ML) 11000 2100 K820 K770 4000 4100 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K17000 2800 370 K150 450 K850 DATB OCT 1990 24... DEC 10... FBB 1991 28... APR 23... JTJN 12... ADO 20... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DI8- (MG/L TOT FLD SOLVED AS CACO3) CAC03 74 130 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 18 7.1 18 30 13 33 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, NAT WH SULFATB RIDE, DIS- TOT PET SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L AS K) 80 1 19 7.9 23 0.9 4.9 1 4.4 1 7.7 CACO3 80 130 130 136 140 80 (MG/L <0.5 14 <0.5 19 22 (MG/L AS S) AS S04) AS CL) 21 36 26 DATE OCT 1990 24... DEC 10... FBB 1991 28... APR 23... JUN 12... AUG 20... FLUO- SILICA, RIDB, DI8- DIS- SOLVED SOLVED (MG/L (MG/L AS SOLIDS, RESIDUE SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- AS F) <0.10 0.10 0.10 SI02) 25 34 20 CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, TUENTS, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL SOLVED PER PBNOBD (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 156 10.7 251 174 56 3 7 13 5 9 0.770 1.21 1.12 1.19 0.730 0.930 0.130 0.090 0.080 0.110 0.110 0.170 0.900 1.30 1.20 1.30 0.840 1.10 0.240 0.640 0.380 0.370 0.730 0.660 0.96 0.76 0.82 1.0 1.1 2.4 K * non-ideal count 264 RIO GRANDE DB LOIZA BASIN 50057025 RIO GDRABO HEAR GORABO, PR--Continued MATER-QUALITY DATA, MATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 24... DEC 10... FBB 1991 28... APR 23... JUN 12... AUG 20... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.2 1.4 1.2 1.4 1.8 3.1 NITRO- NITRO- PHO8- GBN, GEN, PHORUS ARSENIC TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L (UG/L 2.1 2.7 2.4 2.7 2.6 4.2 BARIUM, TOTAL RECOV- ERABLE (UG/L AS N) AS N03) AS P) 9.3 12 11 12 12 19 0.300 0.520 0.410 0.620 0.710 0.680 200 <100 BORON, CADMIUM TOTAL TOTAL RECOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS AS) AS BA) AS B) 30 50 AS CD) <1 <1 CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) COPPER, TOTAL RECOV- ERABLE (UG/L AS CD) 20 DATE OCT 1990 24... DEC 10... FBB 1991 28... APR 23... JUN 12... AUG 20... IRON, TOTAL RECOV- ERABLE (UG/L AS PB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HO) SBLB- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 4400 570 280 610 <0.10 <0.10 20 <0.010 <0.010 0.03 0.06 265 RIO GRANDE DE LOIZA BASIN SOOS83SO RIO CANAS AT RIO CANAS, PR LOCATION.—Lat 18°17'41-, long 66°02'44', Hydrologie Unit 21010005, at right bank, off road 798, upstream side of bridge on Highway 52, .5 mi (.8 km ) northeast Bscuela Segunda Unidad de Francisco Vald6s and .8 mi (1.3 km) north of La Barra. DRAINAGE ARBA.—7.53 mi a (19.50 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1990 to current year. QAGB.—Hater-stage recorder and crest-stage gage. Elevation of gage is 164 ft (SO m), from topographic map. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. EXTREMES FOR PERIOD MARCH TO SEPTEMBER 1990 AND WATER YEAR 1991.—Peak discharges greater than base discharge of 800 ftVs (22.6 mVs) and maximum (*) t Date Time Sept. 3,1990 1745 Oct. 7,1990 1715 Oct. 17 1530 Discharge (ftVs) (mVs) •404 850 3,830 11.4 24.1 108 Gage height (ft) (m) •12.41 14.11 •20.55 3.782 4.301 6.264 Date Time Discharge (ftVs) (mVs) Gage height (ft) (m) Oct. 18,1990 1330 Feb. 5,1991 1605 1,610 1,400 45.6 39.6 16.27 15.74 4.959 4.798 Minimum discharge, 2.7 ftJ/« (0.076 m1/*), July 11, 1990; 2.9 ft1/* (0.082 mVs), May 3-5, 1991. DISCHARGE, CUBIC FEET PER SECOND, MATER YBAR OCTOBER 1989 TO SEPTEMBER 1990 DAILY MEAN VALUES DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SBP e4.4 4.2 10 5.3 9.1 10 46 34 6.9 20 7.6 5.2 4.6 4.3 4.2 4.0 3.9 3.7 3.7 4.1 4.5 4.2 3.9 3.7 3.7 _ _ —— —— —— 3.7 3.5 3.5 3.4 3.4 3.3 3.3 3.3 3.2 3.2 3.4 3.3 3.4 3.6 3.5 3.4 3.3 5.8 4.1 4.2 3.5 3.4 3.3 3.2 4.7 3.6 3.1 3.1 3.1 3.2 —— 106.0 3.53 5.8 3.1 210 .47 .52 3.6 3.6 3.3 3.1 3.0 3.0 3.0 3.0 6.5 4.1 3.3 3.8 4.0 4.3 3.6 3.2 3.2 3.2 3.1 3.0 3.0 3.0 3.0 2.9 2.8 2.8 2.9 2.9 2.9 2.9 2.9 102.9 3.32 6.5 2.8 204 .44 .51 3.8 4.0 3.9 3.8 3.6 3.5 3.3 3.3 3.3 3.7 3.4 3.3 3.3 7.2 8.6 4.7 4.0 3.9 3.8 3.8 3.8 4.1 4.3 4.3 4.3 4.1 3.8 3.7 3.7 3.5 —— 121.8 4.06 8.6 3.3 242 .54 .60 4.1 3.6 3.3 3.8 4.0 3.7 3.5 3.3 3.2 3.2 2.9 2.9 3.0 3.2 3.3 3.4 4.2 4.0 3.2 3.0 2.9 2.8 3,6 4.4 3.9 3.9 3.4 3.1 2.9 2.9 2.8 105.4 3.40 4.4 2.8 209 .45 .52 2.8 3.8 3.4 2.9 3.0 3.1 5.2 4.4 16 £.1 5.1 £.3 5.7 5.1 4.0 3.7 3.6 3.5 3.5 3.5 3.5 3.5 3.7 3.6 4.9 4.1 3.6 3.4 3.4 3.4 3.4 135.2 4.36 16 2.8 268 .58 .67 3.4 3.4 43 6.9 4.4 3.9 20 6.1 4.4 4.2 4.1 4.0 4.3 5.3 5.3 4.4 4.2 4.4 4.9 6.8 4.7 4.6 3.9 4.0 3.9 3.9 4.6 4.2 3.9 6.1 —— 191.2 6.37 43 3.4 379 .85 .94 Estimated 266 DAY OCT RIO GRANDE DE LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR—Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES NOV DEC JAN FBB MAR APR MAY JON JDIi AOQ WTR YR 1991 TOTAL 4143.1 MEAN 11.4 MAX 292 MIN 2.9 AC-FT 8220 CFSM 1.51 IN. 20.47 • Estimated SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. 4.8 4.0 7.1 12 6.7 5.0 73 9.4 6.8 58 14 7.5 6.8 6.0 34 10 292 180 57 54 139 26 14 24 63 47 19 13 11 9.7 9.0 1222.8 39.4 292 4.0 2430 5.24 6.04 8.3 7.8 7.6 7.3 7.3 7.3 6.9 6.9 6.8 6.6 6.8 6.7 6.3 6.1 6.1 6.5 6.6 6.1 6.1 8.8 6.8 7.7 6.3 6.0 6.1 6.1 6.3 6.1 7.0 18 —— 215.3 7.18 18 6.0 427 .95 1.06 12 17 42 13 9.4 8.1 7.5 7.3 7.3 7.2 6.9 6.9 6.9 15 7.1 6.9 6.5 6.7 6.4 6.1 6.2 7.2 6.8 7.2 6.4 6.3 6.1 8.2 41 27 43 371.6 12.0 43 6.1 737 1.59 1.84 19 10 8.1 7.3 7.1 8.5 7.3 7.9 7.2 7.4 6.7 6.5 6.3 6.0 5.8 6.1 5.9 5.7 5.7 5.7 5.6 5.3 5.3 5.3 5.3 5.3 5.1 5.2 5.2 5.1 6.8 209.7 6.76 19 5.1 416 .90 1.04 5.8 5.4 5.3 5.3 140 29 11 8.5 7.5 6.7 8.8 7.9 8.0 6.5 6.4 6.2 5.7 11 10 9.1 7.1 6.8 6.3 5.8 5.5 5.4 5.3 22 —— 368.3 13.2 140 5.3 731 1.75 1.82 6.9 6.2 6.0 6.2 6.8 12 6.2 5.7 5.7 5.2 5.2 5.2 5.2 5.2 5.0 4.7 4.7 5.2 4.9 4.6 4.5 16 5.9 4.9 4.6 5.9 5.2 4.4 4.0 3.9 3.8 179.9 5.80 16 3.8 357 .77 .89 4.1 4.0 4.0 3.8 3.8 3.8 3.7 7.1 4.3 3.8 3.8 4.4 4.6 5.1 19 5.5 4.4 4.2 3.8 3.8 3.7 3.5 3.5 3.3 3.2 3.2 3.2 3.2 3.3 6.1 —— 137.2 4.57 19 3.2 272 .61 .68 3.8 3.2 3.2 2.9 3.0 3.7 3.8 167.1 67 7.4 5.0 4.9 : 4.4 : 4.1 : 4.2 : 4.1 : 37 ( s.s : 6.6 5.6 4 6.3 : 5.1 ! 4.8 4 8.6 : 40 : 6.6 : 5.4 1 5.0 14 4.7 11: 4.5 296.5 25C 9.56 8. 67 J 2.9 : 588 4 1.27 1 1.46 1 .9 118 .7 5.5 .4 8.2 .2 5.6 .9 4.9 .5 4.6 .4 12 .3 6.0 .1 5.0 .1 4.5 .0 4.4 .7 4.3 1.9 4.2 1.8 4.1 1.5 22 1.4 83 1.5 8.7 5.5 54 1.9 13 1.9 7.5 1.1 6.2 1.8 20 5.9 8.7 1.0 6.8 1.6 5.9 1.6 5.5 1.5 5.6 ».8 33 I 7.2 t 11 13 >.9 502.4 36 16.2 L12 118 1.4 4.1 198 997 11 2.15 24 2.48 7.5 6.2 5.9 18 7.1 6.2 5.7 5.7 5.6 5.2 5.2 5.0 5.0 5.0 5.0 5.0 e4.8 e4.8 e4.7 e4.7 5.8 7.6 5.4 4.8 14 5.0 32 7.9 5.8 4.7 4.5 219.8 7.09 32 4.5 436 .94 1.09 4.4 4.2 4.1 4.2 4.2 4.2 6.0 4.4 4.0 3.9 3.9 4.0 3.9 3.8 3.7 3.8 20 4.8 4.2 4.2 6.8 13 4.8 6.6 4.5 4.1 4.4 4.5 9.1 11 —— 168.7 5.62 20 3.7 335 .75 .83 WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1990 TO SEPTEMBER 1991 DATE TIME FEB. 02 1333 JUN. 06 1203 STRBAMFLOW, INSTANTANEOUS (CFS) 4.04 3.82 SPECIFIC CON- TBMPBRA- DUCTANCE TURK (OMHOS) (DBG C) DATE STREAMFLOH, SPECIFIC CON- TEMPERA- TIME INSTANTANEOUS DUCTANCB TURB (CFS) (UMHOS) (DBG C) 332 350 25.0 24.5 JUL. 10 1507 AUG. 13 1308 4.44 4.98 335 330 28.5 26.5 > M H OW fT i I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I w w w * * * I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I WWW** **UI«4O oloJW OM W l HHW W IAMWM I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I •4WWV6WW I I I I I II I I I I I ; W II I I I I I IA W I I I I I I I ... I I I I I I I M H H I I I I I I I e oil i i i i i O) 268 RIO GRANDS DB LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YBAR OCTOBER 1989 TO SEPTEMBER 1990 MEAN MEAN CONCEN- SEDIMENT MEAN DISCHARGE TRATION DISCHARGE DISCHARGE DAY (CFS) (MG/L) (TOMS/DAY) (CFS) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 3.7 3.5 3.5 3.4 3.4 3.3 3.3 3.3 3.2 3.2 3.4 3.3 3.4 3.6 3.5 3.4 3.3 5.8 4.1 4.2 3.5 3.4 3.3 3.2 4.7 3.6 3.1 3.1 3.1 3.2 —— APRIL 7 6 6 6 6 6 6 6 5 5 4 4 3 3 3 2 2 16 33 20 8 6 6 6 10 6 4 3 3 3 —— .06 .06 .06 .06 .06 .06 .06 .06 .05 .04 .04 .04 .02 .02 .02 .02 .02 .66 .39 .24 .08 .06 .06 .06 .17 .07 .03 .02 .02 .02 3.6 3.6 3.3 3.1 3.0 3.0 3.0 3.0 6.5 4.1 3.3 3.8 4.0 4.3 3.6 3.2 3.2 3.2 3.1 3.0 3.0 3.0 3.0 2.9 2.8 2.8 2.9 2.9 2.9 2.9 2.9 MEAN CONCBN- SEDIMENT TRATICM DISCHARGE (MG/L) (TONS/DAY) MAY 3 3 3 3 3 3 3 2 18 10 5 7 14 12 6 5 5 5 5 5 5 5 5 .03 .03 .02 .02 .02 .02 .02 .02 .69 .11 .04 .09 .14 .16 .06 .04 .04 .04 .04 .04 .04 .04 .04 .04 .04 .04 .04 .04 .04 .04 .04 MEAN DISCHARGE (CPS) 3.8 4.0 3.9 3.8 3.6 3.5 3.3 3.3 3.3 3.7 3.4 3.3 3.3 7.2 8.6 4.7 4.0 3.9 3.8 3.8 3.8 4.1 4.3 4.3 4.3 4.1 3.8 3.7 3.7 3.5 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 6 5 7 6 5 7 7 5 5 5 6 5 5 23 24 14 13 12 11 10 10 10 9 7 7 6 5 5 5 5 .08 .06 .11 .07 .05 .07 .06 .04 .04 .05 .06 .05 .04 .98 .59 .17 .14 .13 .11 .10 .10 .11 .11 .09 .08 .07 .06 .05 .04 .04 TOTAL 106.0 2.63 102.9 2.11 121.8 3.75 269 RIO GRANDS DB LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR--Continued SEDIMENT DISCHAROB, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 IAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) 4.1 3.6 3.3 3.8 4.0 3.7 3.5 3.3 3.2 3.2 2.9 2.9 3.0 3.2 3.3 3.4 4.2 4.0 3.2 3.0 2.9 2.8 3.6 4.4 3.9 3.9 3.4 3.1 2.9 2.9 2.8 MEAN CONCEN- SEDIMENT TRATION DISCHAROB (MQ/L) (TONS/DAY) JULY 6 5 5 5 6 6 5 5 5 5 4 4 4 5 5 5 8 10 10 10 10 10 10 21 24 21 16 12 10 10 10 .07 .05 .04 .05 .07 .06 .05 .05 .04 .04 .04 .04 .04 .04 .05 .05 .10 .11 .09 .08 .08 .08 .10 .27 .26 .22 .15 .10 .08 .08 .08 MEAN DISCHAROB (CPS) 2.8 3.8 3.4 2.9 3.0 3.1 5.2 4.4 16 6.1 5.1 6.3 5.7 5.1 4.0 3.7 3.6 3.5 3.5 3.5 3.5 3.5 3.7 3.6 4.9 4.1 3.6 3.4 3.4 3.4 3.4 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) AUGUST MEAN MEAN CONCEN- SEDIMENT DISCHAROB TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) SEPTEMBER 10 16 22 20 20 20 21 9 92 19 13 22 34 27 26 24 21 18 15 14 14 14 14 14 16 22 26 15 12 8 6 16 .08 .18 .21 .16 .17 .17 .33 .11 .31 .18 .45 .49 .38 .28 .24 .20 .17 .14 .13 .13 .13 .14 .13 .28 .24 .25 .13 .11 .08 .06 3.4 3.4 43 6.9 4.4 3.9 20 6.1 4.4 4.2 4.1 4.0 4.3 5.3 5.3 4.4 4.2 4.4 4.9 6.8 4.7 4.6 3.9 4.0 3.9 3.9 4.6 4.2 3.9 6.1 6 7 1220 210 60 45 197 119 20 20 20 20 70 29 109 59 58 59 62 60 50 33 22 16 16 16 16 15 15 20 .06 .07 587 5.0 .75 .48 45 2.5 .24 .22 .22 .21 .91 .49 1.4 .70 .66 .68 .80 1.0 .68 .39 .23 .16 .16 .16 .18 .18 .15 .46 TOTAL 105.4 2.66 135.2 22.06 191.2 651.14 270 RIO ORANDB DB LOI2A BASIN 50058350 RIO CANAS AT RIO CAftAS, PR—Continued SBDIHBNT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 4.8 4.0 7.1 12 6.7 5.0 73 9.4 6.8 58 14 7.5 6.8 6.0 34 10 292 180 57 54 139 26 14 24 63 47 19 13 11 9.7 9.0 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MQ/L) (TONS/DAY) MEAN DISCHARGE (CPS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MQ/L) (TONS/DAY) OCTOBER 14 8 20 113 224 25 895 55 33 957 575 58 25 20 718 218 1150 1080 175 409 1430 157 94 198 748 513 . 19 16 13 11 10 NOVEMBER MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MQ/L) (TONS/DAY) DECEMBER .19 .09 .54 9.6 4.6 .37 1150 1.7 .62 558 24 1.2 .43 .32 220 7.8 4920 1520 35 188 929 13 3.7 40 327 124 1.0 .57 .37 .29 .23 8.3 7.8 7.6 7.3 7.3 7.3 .9 .9 .8 .6 .8 .7 .3 .1 .1 .5 .6 .1 .1 .8 .8 .7 .3 .0 .1 .1 .3 .1 7.0 18 9 8 8 8 8 7 6 5 5 5 5 5 4 4 4 3 3 3 4 22 20 19 14 10 9 9 6 5 15 99 .19 .17 .16 .16 .16 .15 .13 .11 .09 .08 .09 .09 .07 .06 .06 .06 .06 .06 .06 1.1 .38 .40 .25 .16 .14 .14 .10 .08 .37 15 12 17 42 13 9.4 8.1 7.5 7.3 7.3 7.2 6.9 6.9 6.9 15 7.1 6.9 6.5 6.7 6.4 6.1 6.2 7.2 6.8 7.2 6.4 6.3 6.1 8.2 41 27 43 42 41 863 44 19 11 10 10 10 9 9 9 9 77 10 10 8 8 10 16 20 20 19 16 16 14 12 28 380 206 351 1.8 2.0 213 1.7 .48 .25 .21 .20 .19 .17 .16 .16 .16 12 .20 .18 .15 .14 .17 .26 .35 .37 .32 .31 .27 .24 .19 .75 239 51 150 TOTAL 1222.8 10081.62 215.3 20.13 371.6 676.38 271 RIO ORANDB DE LOISA BASIN SOOS83SO RIO CANAS AT RIO CANAS, PR—OontilMMd SEDIMENT DISCHARGE, SD8PBNDBD (TONS/DAY), MATER YEAR OCTOBER 1990 TO SBPTRMBBR 1991 kAY 1 3 3 4 5 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MBAN DISCHARGE (CPS) 19 10 8.1 7.3 7.1 8.5 7.3 7.9 7.2 7.4 6.7 6.5 6.3 6.0 5.8 6.1 5.9 5.7 5.7 5.7 5.6 5.3 5.3 5.3 5.3 5.3 5.1 5.2 5.2 5.1 6.8 MBAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JANUARY 85 21 14 13 13 12 11 13 14 10 7 7 6 35 6 5 4 4 4 3 3 3 2 2 2 4 5 5 4 3 2 MBAN MBAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) FEBRUARY 6.2 .59 .31 .25 .24 .27 .23 .27 .29 .21 .13 .13 .11 .53 .10 .09 .07 .06 .06 .05 .04 .04 .03 .02 .02 .05 .07 .08 .07 .05 .04 5.8 5.4 5.3 5.3 140 29 11 8.5 7.5 6.7 8.8 7.9 8.0 6.5 6.4 6.2 5.7 11 10 9.1 7.1 6.8 6.3 5.8 5. 5 5.4 5.3 22 2 2 2 2 1200 230 33 23 19 17 24 20 18 6 6 6 6 30 31 16 14 12 8 4 3 3 2 688 .03 .02 .02 .03 2790 SO 1.1 .53 .38 .31 .70 .48 .44 .11 .10 .10 .10 1.7 1.0 .38 .26 .22 .15 .07 .04 .04 .03 300 MBAN DISCHARGE (CPS) .9 .2 .0 .2 .8 12 6.2 5.7 5.7 5.2 5.2 5.2 5.2 5.2 5.0 4.7 4.7 5.2 4.9 4.6 4.5 16 5.9 4.9 4.6 5.9 5.2 4.4 4.0 3.9 3.8 MBAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MARCH 14 6 6 6 6 42 13 10 10 10 18 12 10 10 10 10 10 10 10 10 10 68 14 7 6 12 IS 11 11 10 7 .28 .10 .10 .10 .11 2.4 .21 .16 .15 .14 .25 .16 .14 .14 .13 .12 .12 .13 .13 .12 .12 5.2 .23 .09 .08 .25 .21 .13 .12 .11 .08 TOTAL 209.7 10.70 368.3 3148.34 179.9 11.81 272 RIO ORANDB DB LOIZA BASIN 50058350 RIO CARA8 AT RIO CANAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YBAR OCTOBER 1990 TO 8BFTBMBBR 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 4.1 4.0 4.0 3.8 3.8 3.8 3.7 7.1 4.3 3.8 3.8 4.4 4.6 5.1 19 5.5 4.4 4.2 3.8 3.8 3.7 3.5 3.5 3.3 3.2 3.2 3.2 3.2 3.3 6.1 MEAN DISCHARGE (CFS) APRIL 6 5 4 4 4 4 5 29 27 12 4 6 8 11 90 13 8 9 7 5 4 4 4 5 5 6 8 10 10 22 MEAN COHCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) HAY .06 .06 .05 .04 .04 .04 .04 .76 .35 .12 .05 .09 .11 .14 12 .23 .10 .10 .08 .05 .04 .04 .04 .04 .04 .05 .07 .08 .08 .85 3.8 3.2 3.2 2.9 3.0 3.7 3.8 16 7.1 67 7.4 5.0 4.9 4.4 4.1 4.2 4.1 37 8.S 6.6 5.6 6.3 5.1 4.8 8.6 40 6.6 5.4 5.0 4.7 4.5 9 7 6 6 6 6 6 119 78 602 29 14 8 6 6 7 6 350 27 20 14 14 11 10 12 443 17 11 11 10 9 .10 .06 .05 .04 .05 .07 .07 12 1.7 612 .69 .19 .10 .07 .06 .08 .06 150 1.1 .46 .23 .24 .14 .11 .29 378 .33 .15 .13 .11 .10 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MO/L) (TONS/DAY) JUNE .9 .7 .4 .2 .9 .5 .4 .3 .1 .1 .0 .7 3.9 3.8 3.5 3.4 3.5 6.5 3.9 7.9 4.1 3.8 5.9 4.0 3.6 3.6 3.5 6.8 14 112 10 10 7 5 6 10 9 7 5 4 3 3 2 2 2 2 3 18 8 32 8 6 26 31 23 18 16 27 433 572 .11 .11 .08 .06 .08 .11 .11 .08 .06 .05 .04 .04 .03 .02 .02 .02 .03 1.4 .09 3.1 .09 .07 .52 .34 .22 .17 .15 1.1 43 411 TOTAL 137.2 15.84 296.5 1158.78 250.9 462.30 M 91 VI «0 OB «J M VI -O * VI 08 VI 0» H M Ul » VI O O 01 «O VI M VI I VI * M fl» l «e MHMM OB O H Ul * •OOBUI M 91 * Ul M * 9i 9i » Ul O «J MOP 9< M M VB VI VI H VI Ul OH M M-O M »0 91 OOOO O H 91 H H W «J * 00 -O OB H O «J Ul VI VI VI 9i 9< 9< 91 9i * 91 H Ul Ul 9i 9i *- M M Ul H •••• H . «0 »»VI«JMVI * * VI «J VI * * » » VI VI VI VI VI VI VI VI VI VI 91 -OOBtfl»*J OB VI -O OB «0 O OB * 91 OB «J «J OB 0» O OOOOM M 91 «J «J M M VB M VI I M H* M I Ul M M to H* M BJ (§ (§ (§ 0 H* H* BJ ^ M M M I UIUI«dOMVI M VI -O * VI VI Ul VI VI VI Ul VI VI VI VI VIVI9I09I 9l M VI O «O M VI * M VI M O 910 •••• VB OH I H O M MM-JO OOOOO 00000 OOOMM VI M i»> H VI Ul OB 9i9i9i9i9i 9i 9i 9i OB OB OB «O * 9i * 9i Ul H M WlJhOB OB MMOB OB ^1 OB W O VD VB O i»> O M M M H M » I I M II^M H H «J M M* H I I OBOBMUIUI WOBOMH VI 91 H O * MMMMM M 9l VB M M M M M M Ul VI H» Ul Ul » K H * . (..... ... . ... . ..... ..... ..... M I M H O O O H «J H -O OOH O OOOOO O O M Ul O M I MUI9I HO* «0 91 «J * * MMMMM Ul 91 O M M til H a i S UI VI It O i a K V O - H Sin * K I I 8 10 -4 CO 274 RIO ORANDE DB LOIZA BASIN 50058350 RIO CANA8 AT CA&AS, PR--Continu«d WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1990 07... 10... 17... 25... FBB 1991 05... MAY 26... JXJN 30... 30... JUL 16... TIME 1625 0900 1455 2255 1600 1345 1240 1250 1000 DIS- CHARGE, INST. CUBIC FEET PER SECOND SEDI- MENT, SUS- PENDED (MQ/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 345 8 2590 311 1390 526 537 547 485 4050 840 9040 3770 10530 5130 8120 6620 3970 377 19 63200 3160 39500 7300 11800 9800 5200 21 55 8 15 27 26 26 30 16 39 68 19 27 38 35 35 41 25 55 84 29 43 51 51 52 53 41 DATE OCT 1990 07... 10... 17... 25... FBB 1991 05... 26... JUN 30... 30... JUL 16... SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 80 86 46 62 64 62 61 68 55 84 92 68 74 76 74 76 79 70 98 100 84 92 87 89 90 92 88 99 100 91 97 94 96 95 97 94 100 100 96 99 98 99 98 99 97 100 98 100 99 100 99 100 99 100 99 100 100 100 100 100 100 275 RIO GRANDS DB LOIZA BASIN 50058350 RIO CANA8 AT CANAS, PR—Continued WATER QUALITY DATA, WATER YBAR OCTOBER 1989 TO SEPTEMBER 1990 SIM- AND CLAY PERCENT OP SUSPENDED SEDIMENT DATB JUL 1990 17... AUG 11... SEP 03... 03... 04... TIME 1305 1335 1725 1835 0910 STREAM- PLOW, INSTAN- TANEOUS (CPS) 5.2 4.2 337 228 6.3 SEDI- MENT, SUS- PENDED (MG/L) 925 2640 7150 6110 246 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 13 30 €500 3760 4 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 99 96 99 61 276 RIO ORANDB DB LOIZA BASIN 50058350 RIO CANA8 AT CANAS, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OP SUSPENDED SEDIMENT DATE OCT 1990 07... 11... 25... 26... DEC 03... FHB 1991 05... 05... 28... MAY 26... JDN 30... 30... JUL 16... TIME 1905 1048 2350 0025 1017 1630 1750 1415 1435 1220 1410 1040 STREAM- PLOW, INSTAN- TANEOUS (CPS) 184 16 184 146 116 1180 446 198 209 359 200 494 SEDI- MENT, SUS- PENDED (MQ/L) 2800 475 2600 5400 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 1400 20 1300 2130 2200 8220 3240 6920 4760 8020 2160 3170 700 26200 3900 3700 2700 7800 1200 4200 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 99 97 96 96 91 89 91 94 92 89 90 RIO QRANDE DE LOIZA BASIN 277 50059000 LAOO LOIZA AT DAMSITB, PR LOCATION.—Lat 18°19'49", Long 66°01'00", Hydrologic Unit 21010005, at pump site at damsite, and 1.9 mi (3.1 km) south of Trujillo Alto plama. DRANAIGE AREA.--208 mi» (539 km*). ELEVATION RECORDS PERIOD OF RECORD.--December 1987 to current year. GAGE.—Water-stage recorder. Datum of gage is mean sea level. REMARKS.—Lake is formed by Loima Dam, a concrete structure completed in 1954. Useable capacity of impoundment is 30,000 acre-ft (37.0 bm3). Out flow from lake is controlled by five slid* gate* in powerplant and pump intake structure, four •luice gate*, and concrete spillway witb eigbt radial gate*. Lake is used for municipal water supply and intermittent power generation. Gage-height satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.—Maximun elevation 147.42 ft (44.93 m), Sept. 18, 1989; minimun elevation, 125.86 ft (38.36 m), June 12, 1988. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation 135.17 ft (41.20 m), Dec. 31, Mar. 6; minimum elevation, 127.93 ft (38.99 m), June 30. Capacity Table (based on data from Puerto Rico Electric Power Authority) Elevation, in feet 98.4 111.5 120.4 Contents in acre-feet 5 8.9 13 Elevation, in feet 128.6 137.8 147.6 Contents in acre-feet 18 26 35 ELEVATION (FEET NOVD), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY OBSERVATION AT 24iOO VALUES DAY OCT NOV 1 133.90 134.42 2 133.96 134.48 3 134.06 134.28 4 134.20 134.03 5 132.44 133.98 6 132.46 134.70 7 132.23 134.56 8 132.64 134.69 9 132.98 134.57 10 132.73 134.39 11 133.36 134.63 12 133.64 134.83 13 134.04 134.47 14 133.78 134.63 15 132.92 134.53 1C 132.74 134.51 17 133.08 134.25 18 132.46 134.37 19 133.86 134.49 20 133.38 134.49 21 22 23 24 25 26 27 28 29 30 31 MEAN 133.42 134.54 134.77 134.68 134.69 MAX 134.42 134.89 135.01 135.00 135.08 MIN 132.23 133.98 133.95 134.25 134.04 DEC 134.47 134.93 134.71 134.77 134.72 134.84 134.92 135.00 134.58 134.66 134.84 134.76 134.82 134.98 134.46 134.76 134.90 135.00 134.68 134.72 JAN 134.25 134.97 134.56 134.80 134.46 134.72 134.78 134.54 135.00 134.CO 134.94 134.42 134.CO 134.77 134.97 134.45 134.55 134.65 134.71 134.75 FEB 134.64 134.CC 134.CC 134.68 134.86 134.04 134.56 134.64 134.68 134.68 134.44 135.08 134.96 134.58 134.78 134.86 134.91 134.14 134.84 134.50 MAR 134.68 134.67 134.69 134.81 134.91 134.39 134.52 134.74 134.90 134.95 134.46 134.45 134.44 134.42 134.38 134.32 134.25 134.23 134.23 134.19 APR 134.36 134.24 134.12 134.00 133.87 133.71 133.56 133.67 133.63 133.57 133.52 133.56 133.54 133.48 133.54 133.53 133.43 133.31 133.21 133.05 MAY 131.21 130.98 130.77 130.57 130.39 130.22 130.12 130.1C 130.13 130.59 131.00 131.54 131.55 131.43 131.34 131.28 131.14 131.37 131.73 131.84 JUN 132.1C 132.09 131.93 131.75 A 129.94 129.73 129.57 JUL 134.01 134.CO 133.94 134.OC 134.04 133.98 133.98 133.94 133.82 133.68 133.50 133.32 133.14 133.01 133.49 134.52 134.43 134.20 133.26 133.34 AUG 133.29 133.19 133.03 132.93 132.80 132.CO 132.44 132.26 132.05 131.85 131.65 A A A A 130.72 130.74 131.28 131.26 131.13 SEP 134.56 134.58 134.46 134.34 134.1C 134.02 133.99 133.89 133.95 134.05 134.01 133.91 133.75 133.59 133.41 133.25 134.15 133.65 134.00 134.08 132.73 133.90 133. 1C 133.94 134.04 134. OC 134.33 133.74 133.28 133.44 134.42 134.81 134.49 134.63 134.73 134.77 134.57 134.83 134.58 134.75 134.89 134.78 134.80 134.86 134.91 134.93 134.91 134.91 135.01 134.53 134.69 133.95 134.76 134.75 134.75 134.74 134.72 134.72 134.70 134. CC 134.62 134.56 134.58 134.82 134. CO 134.69 134.75 134.81 134.89 134.92 134. CO ___ ___ 134.11 134.62 134.76 134.73 134 . 64 134.88 134.85 134.79 134.69 134.59 134.47 132.92 A A 132.45 132.31 132. 1C 131.99 131.79 131.63 131.42 131.79 131.90 131.88 131.74 132.71 132.99 132.92 132.78 132 . 62 132.45 132.29 129.36 129.28 129.18 129.02 128.84 128.63 128.39 128.19 128.00 131.58 133.32 133.56 133.52 133 . 54 133.52 133.42 133.32 133.50 133.40 133.34 133.38 131.33 132.05 132.53 132.53 132.51 132.37 134.75 134 . 17 134.44 134.50 134.50 134.28 134.26 134.08 134.50 133.48 133.50 133.74 134.28 133.86 133.56 —— 134.57 134.95 134.11 131.47 132.99 130.12 133.68 134.CO 133.01 133.98 134.58 133.25 A No gage-height record. 278 RIO QRANDB IX LOIZA BASIN 50059000 LAGO LOIZA AT DANSITB, PR WATER-QUALITY RECORDS LOCATION. —Lat 18»19'49", long 66»01'00", at puaphouse at dam*ita, and 1.9 mi (3.1 km) aouth of Tru- jillo Alto plaia. DRAINAGE ARBA.—208 mi* (539 km3). PERIOD OF RBCORO.—Watar yean 1974 to currant yaar. WATBR-QDALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATS OCT 1990 26... DBC 04... FBB 1991 07... APR 11... JON 13... ADO 14... DATS OCT 1990 26... DBC 04... FBB 1991 07... APR 11... ODN 13... AOQ 14... TIME 1120 1210 1215 1215 0930 1020 SULFIDE TOTAL (MO/L AS S) <0.5 — — <0.5 -- — SPE- CIFIC CON- DUCT- ANCE (US /CM) 168 310 30 320 340 270 RESIDUE TOTAL AT 105 DBQ. C, SUS- PENDED (MQ/L) 98 <1 13 22 10 15 PH (STAND- ARD UNITS) 7.0 7.1 6.9 7.1 7.1 7.1 NITRO- GEN, NITRATE TOTAL (MQ/L AS N) 0.450 0.530 0.450 0.190 -- — TEMPER- ATURE WATER (DBQ C) 27.0 26.5 25.5 26.5 29.0 30.0 NITRO- GEN, NITRITE TOTAL (MQ/L AS N) 0.150 0.070 0.050 0.020 0.010 <0.010 OXYGEN, DIS- SOLVED (MQ/L) 3.6 2.6 4.6 2.8 2.0 2.0 NITRO- GEN, N02+N03 TOTAL (MQ/L AS N) 0.600 0.600 0.500 0.210 <0.050 <0.050 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 45 32 56 35 26 27 NITRO- GEN, AMMONIA TOTAL (MQ/L AS N) 0.260 0.420 0.190 0.050 0.320 0.240 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MQ/L) 35 10 22 16 14 37 NITRO- GEN, ORGANIC TOTAL (MQ/L AS N) 0.74 0.28 0.51 0.75 0.78 1.7 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K720 K22 K740 46 K14 1000 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MQ/L AS N) 1.0 0.70 0.70 0.80 1.1 1.9 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 210 75 840 K8 39 84 NITRO- GEN, TOTAL (MQ/L AS N) 1.6 1.3 1.2 1.0 — — ALKA- LINITY WAT WH TOT FET FIELD MG/L AS CAC03 51 98 97 110 110 84 NITRO- GEN, TOTAL (MG/L AS NO3) 7.1 5.8 5.3 4.5 — — BORON, COPPER, IRON, PHOS- TOTAL TOTAL TOTAL PHORUS RECOV- RBCOV- RBCOV- TOTAL BRABLB BRABLB BRABLB DATS (MQ/L (UG/L (UG/L (UG/L AS P) OCT 1990 26... DBC 04... FBB 1991 07... APR 11... OUN 13... ADO 14... 0.270 0.190 0.220 0.150 0.420 1.20 AS B) 40 50 30 10 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L ZINC, TOTAL RBCOV- CYANIDE BRABLB TOTAL (UG/L (MQ/L 6200 730 250 160 70 <0.010 80 <0.010 MBTHY- LENE BLUB ACTIVE PHENOLS SUB- TOTAL STANCE AS CD) AS FB) AS MN) AS ZN) AS CN) (UG/L) (MQ/L) <0.01 0.02 K« non-ideal count a»K M r» «* P« M o 9IHW 00 00 <« oo oo oo oo oo r> M 9i eo r> c- c- c- c- vo r» oo in 01 oo PI « • oo r> H vo PI PI PI «* H • • • ve oo •* 1/1 01 n o <* o oo r- • vo n • in r- oo vo H n 01 vo • . r>n9i9ive vevevo<«in «* o oo oo oo oo o n n H <* r» 01 o oo oo vo •* o 91 in •* H oo o 01 ifl ..... ..... ..... ..... ..... .. ... . .00 • 00 H H in vo in in in in in in in in M M «* «* •* -«inini/)vo in mining •« in H oo vo r» oo r» ve «* ve • • 9i vo vo vo w vo <« vo oo in in o oo o ^ o H H . ..... . . ... . n r- -vovor- ^ O1 H d n H H 01 H H H H H H r» O9IMMM MMMMM MM<«IMMM d H r» 1/1 00 • . VO in O H H HHHHtH HHHHH r» O O «* H VO H r- ve n r- 01 01 <* ft r» oo oo PI oo r- r- c^ oo oo oo oo oo oo n oo oo oo oo oo in 01 01 r» vo vo vo vo «o M o oo r» i in vo t^ t^ oo i PI in n n oo < . |»H O H • in- PI r» 91 91 ve 91 91 oo oo oo oo oo oo oo H H in ft H M «* 91 ve 91 M PI 91 00 00 00 00 00 PI r<> 9i M r> 91 00 00 9l 9l 91 PI O 91 t^ 00 00 t^ VO O H H H H M O 00 PI f. *H «H 9j H PI H in o M «* «* 91 91 ve PI o «»"ve • • M • VO H H r» oo M oo c- • • oo n H »H r» o PI o r» 9i • -ci • H PI PI M r» «* r» PI • • r- r- <• 1 PI 00 91 H M n H H M «* H 91 91 91 00 i « vo vo r» <« oo oo oo oo ve9ieo r> oo in oo in in in • • o M PI O VD •* 91 «• H in vo vo PI •* H n vo inn o ve «H r» r» «• H n H n •* n oo H vo oo •H M H ^ PI PI PI 9i t»«» PI ve ««i 9i r> 9i r» ^ r- n H H M M H H H i-l oo o in 9i vo t^ oo oo et 9\ M 00 9l 9l «* ve PI O o in o H o at H . 10 «• ••« r> 9> 01 H ^ VO H . • H n oo r- o PI H n o r» o 01 oo oot ^ 01 n in n in in r-•* o ver»eo9io n o 9100 r» H ^9i Hin O «* O 00 <« OOHOO o r> PI r> 9i M H «H 9i t> in ve r> r> oo vo n 01 H vo H H ve «H n ve n o 01 o 01 in . «* M • at o ve o M «* 9i r» ve oo oo vo n t«- • • oo ve ve «* r» rt o ve H «* «* 01 vo r- vo 01 n OH m 91 91 I 91 91 -A H H 41 280 RIO CERANDE DE LOIZA BASIN 50059050 RIO CERANDE DE LOIZA BELOW DAMSITE, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.-- Water year* 1987 to current year. INSTRUMENTATION.—— Automatic tediment •ampler. PERIOD OF DAILY RECORD.-- SUSPBNDBD-SBDIMBNT DISCHARGE! December 1986 to September 1991. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION! Maximum daily mean, 628 mg/I> September 18, 1989) Minimum daily mean, 1 mg/L several day*. SEDIMENT LOADSt Maximum daily mean, 79,900 tone (72,710 tonne*) December 8, 1987; Minimum daily mean, 0.03 ton (0.02 tonne*) several day*. EXTREMES FOR CURRENT YEAR.-- SEDIMENT CONCENTRATIONt Maximun daily 1 mg/1 several day*. 274 mg/1 October 21, 1990; minimun daily SEDIMENTS LOADSt Maximun daily mean, 4,920 tone (4,480 tonne*) October 21, 1990t minimum daily mean, 0.03 tone (0.02 tonne*) several day*. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 )AY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 4.8 3.3 12 5.3 982 5.2 525 7.1 4.4 1180 72 10 9.5 140 1590 1500 674 1730 778 894 6650 310 311 1190 2670 2380 665 764 649 377 16 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER 14 11 23 15 58 15 91 17 7 67 43 20 19 58 71 133 99 184 104 108 274 73 73 234 164 157 99 104 98 78 28 .18 .10 .75 .21 154 .21 129 .33 .08 214 8.3 .53 .48 22 306 538 181 859 219 261 4920 61 61 1040 1180 1010 178 214 172 79 1.2 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 162 216 175 272 440 9.8 142 74 123 116 14 9.9 157 9.5 57 56 78 32 6.7 47 14 179 7.1 7.0 7.8 78 8.6 137 8.7 62 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 62 67 63 71 83 21 57 43 54 54 26 20 61 19 39 20 44 35 15 37 26 64 18 17 17 44 19 57 21 41 27 39 30 52 99 .52 22 8.6 18 17 .98 .53 26 .50 6 5.9 9.2 3 .28 4.7 .98 31 .34 .33 .36 9.2 .43 21 .49 6.8 310 6.1 454 169 64 14 12 13 100 13 12 58 11 346 338 17 12 12 68 7.8 7.8 8.0 8.5 9.9 9.6 9.5 9.8 14 216 343 2440 73 16 85 64 41 5 23 24 48 24 23 40 22 75 74 28 8 4 42 18 18 18 18 19 18 19 1 26 67 76 158 61 .27 104 29 7.1 .98 .75 .86 .13 .86 .75 6.2 .64 70 68 1.3 .75 .13 7.7 .37 .37 .40 .42 .52 .48 .48 .03 30.98 39 70 1040 TOTAL 26108.6 11810.37 2706.1 441.14 5113.0 1543.47 281 RIO GRANDB DB LOIZA BASIN 50059050 RIO ORANDB DB LOIZA BBLOH DAMSITB, PR—Continuad SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 IS 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 540 9.2 170 5.3 113 12 153 128 9.8 171 8.1 164 6.5 6.4 7.1 174 8.9 8.9 8.9 8.8 8.6 8.9 8.8 8.4 8.2 8.5 8.7 8.4 7.8 7.6 8.4 1805.2 92 19 S3 35 52 23 60 55 21 S3 18 SI 17 17 17 64 8 19 19 18 19 9 18 18 18 19 20 18 0 18 18 —— 134 .47 29 .50 IS .75 25 19 .56 29 .40 27 .30 .30 .33 .30 .19 .45 .45 .44 .45 .22 .44 .40 .40 .43 .46 .40 .38 .36 .40 288.78 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY 7.9 8.3 8.0 7.9 39S 430 11 11 12 13 145 10 318 193 7.3 7.8 7.8 195 15 1S3 10 72 8.9 8.9 8.S 8.3 8.4 83 —— 2175.1 S 36 19 18 79 83 21 21 23 25 59 60 73 65 18 18 18 65 27 SI 12 43 18 18 19 18 19 45 —— —— .13 .42 .40 .38 84 96 .62 .62 .75 .86 23 l.SO S3 34 .35 .37 .37 34 1.10 27 .32 8.30 .45 .45 .44 .42 .42 10 —— 389.77 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 9.3 8.7 8.9 9.5 9.7 259 137 IS 15 IS 105 19 15 14 14 15 14 14 14 14 15 20 15 14 14 14 15 15 13 13 12 887.1 1 18 19 19 19 70 57 28 27 28 49 29 27 22 26 27 26 26 26 27 30 12 26 26 26 26 12 12 25 25 22 —— .03 .44 .45 .50 .51 49 21 1.20 1.10 1.2 14 1.50 1.10 .83 .98 1.10 .98 .98 .98 1.10 l.SO 1.10 .98 .98 .98 .98 1.1 1.10 .86 .86 .72 110.24 282 RIO GRANDEE DB LOIZA BASIN 50059050 RIO GRANDB DB LOIZA BBLOW DAMSITS, PR--Continued SBDIMEHT DISCHARGEE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCBN- SEDIMENT DISCHARGEE TRATION DISCHARGE DAY (CFS) (MQ/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 12 12 12 11 11 11 11 14 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 11 11 11 11 11 11 11 APRIL 26 26 26 22 22 22 22 26 23 23 7 23 23 23 23 23 23 23 43 23 23 23 23 22 22 22 22 22 22 22 TOTAL 351 e Estimated .75 .75 .75 .64 .64 .64 .64 .98 .75 .75 .23 .75 .75 .75 .75 .75 .75 .75 L.40 .75 .75 .75 .75 .64 .64 .64 .64 .64 .64 .64 21.65 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 11 11 10 14 10 10 11 10 9.6 9.3 8.9 8.9 8.6 8.9 8.9 8.9 8.9 11 11 e25 ell 11 10 9.5 9.5 9.4 8.9 8.6 8.9 8.5 8.3 22 22 19 26 20 20 22 20 39 18 19 19 18 19 19 19 23 22 22 e32 e22 14 20 19 19 19 19 18 19 20 45 .64 .64 .53 .98 .53 .53 .64 .53 .82 .47 .45 .45 .42 .45 .45 .45 .55 .64 .64 e2.2 e.64 .42 .53 .50 .50 .48 .45 .43 .45 .45 1.00 JUNE 8.1 7.7 7.8 7.8 8.3 8.3 8.3 8.3 8.3 8.3 8.2 7.8 7.8 7.8 7.8 7.8 7.5 7.3 7.3 12 7.7 6.7 6.4 6.4 6.0 5.8 6.5 7.0 7.8 8.7 18 17 17 17 19 8 19 19 19 19 19 18 18 18 18 18 18 17 17 125 18 17 16 16 17 16 16 17 18 19 318.5 18.86 231.5 .40 .36 .36 .38 .42 .18 .42 .42 .42 .42 .41 .38 .38 .38 .38 .38 .36 .34 .34 1.00 .37 .30 .28 .28 .27 .25 .29 .33 .37 .45 14.32 283 RIO ORANDB DB LOIZA BASIN 50059050 RIO GRANDS DB LOIZA BELOW DAMSITB, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN DISCHARGE DAY (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 664 53 201 12 12 11 11 13 11 11 11 11 11 11 17 1770 309 305 442 5.9 5.6 5.6 5.6 5.9 5.6 5.4 5.6 14 5.8 5.5 5.5 3962.0 JULY 99 38 66 23 23 22 22 25 22 22 17 22 22 22 28 153 72 72 148 16 15 16 16 16 16 15 16 24 15 6 6 AUGUST YEAR 49372.9 e Estimated 177 5.5 36 .75 .75 .64 .64 .86 .64 .64 .50 .64 .64 .64 1.30 732 60 59 176 .25 .23 .24 .24 .25 .24 .22 .24 .98 .24 .23 .23 1257.73 17414.62 5.7 6.2 5.9 5.9 5.6 5.6 5.6 5.6 5.4 5.5 5.4 5.0 4.8 4.8 4.8 4.8 5.0 5.2 5.2 6.1 5.9 5.7 5.3 5.0 4.8 4.8 5.6 681 8.4 6.0 7.9 848.5 24 16 16 16 15 19 15 15 15 15 15 30 14 13 14 14 15 15 15 16 14 16 15 15 14 14 15 100 18 17 18 183 190.32 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER .37 .27 .25 .25 .23 .29 .23 .23 .22 .23 .22 .40 .18 .17 .18 .18 .20 .21 .21 .27 .22 .24 .21 .20 .18 .18 .23 .42 .27 .38 8.7 8.4 8.3 8.2 8.0 7.4 15 9.9 8.1 7.8 7.8 7.8 7.4 7.1 6.9 6.9 e!220 e811 e7.1 7.1 7.5 e738 e!95 e3.4 e688 e3.7 e3.4 e3.4 e464 e581 19 18 19 19 18 17 27 19 18 18 18 18 18 18 17 17 e!19 elOS e4 17 18 e!36 e64 e3 e84 e!3 e!3 e!3 e85 e!7 .44 .42 .42 .42 .40 .24 1.10 .52 .40 .37 .37 .37 .35 .34 .32 .32 e393 e231 e.08 .33 .36 e271 e34 e.03 e!52 e.13 e.12 e.12 e!07 e!32 4866.3 1327.97 n O A ' RIO ORANDB DB LOIZA BASIN 50059100 RIO ORANDB DB LOIZA BELOW TRUJILLO ALTO, PR WATER-QUALITY RBGORDS LOCATION.—Lat 18°21'35", long 66°00'15 a , 100 ft (30 •) downstream of Highway 181 bridge, 0, northweit of Trujillo Alto plaxa, and 2.2 H! (3.5 km) northeait of Lago Loiia Reservoir. DRAINAQB ARBA.--213 »i2 (552 *•?). PERIOD OV RECORD.--Water year* 1981 to current year. REMARKSi Flow controlled by Lago Loixa reiervoir. WATBR-QDALITY DATA, WATBR YEAR OCTOBER 1990 TO SEPTEMBER 1991 4 Mi (0.6 km) DATE OCT 1990 30... DEC 21... FEB 1991 28... APR 25... JUN 13... ADG 26... TIME 0840 1030 1055 1030 1250 1255 DIS- CHARGE, INST. CUBIC FEET PER SECOND 27 14 16 10 12 9.6 SPE- CIFIC CON- DUCT- ANCE (US/CM) 211 382 422 383 373 383 PH (STAND- ARD UNITS) 7.4 8.3 8.5 8.1 8.4 8.1 TEMPER- ATURE WATBR (DBG C) 26.0 26.0 23.5 31.5 34.0 32.0 TUR- BID- ITY (NTU) 85 2.1 3.4 5.5 4.9 12 OXYGEN, DIS- SOLVED (MG/L) 6.3 9.4 8.4 9.3 9.9 9.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 77 115 98 120 139 116 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 30 10 12 13 18 25 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2900 470 200 K10 K140 2700 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 960 K70 K18 220 K40 K50 DATE OCT 1990 30... DEC 21... FEB 1991 28... APR 25... JUN 13... AUG 26... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS CACO3) CACO3 130 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS MA) 72 0 18 6.6 15 32 13 31 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH SULFATE DIS- TOT PET SULFIDB DIS- SOLVED FIELD TOTAL SOLVED (MG/L MG/L AS (MG/L AS K) 140 0 34 13 30 0.8 4.1 1 2.3 1 3.9 CACO3 ISO 134 ISO 140 140 120 (MG/L <0.5 12 3g »F jj jj 33 H H HO 4 4 S3 -400 W -4 tfl 10 <0» M M M M £ £ •• ss MM MH w w w w o o ii Mtfl -4« 1 1 HH »»4 tfl* 10 tfl OO O O 1 >4 ss M M tfl tfl H H 22 * 8 M * 3 -4« «fc MM G M O O H 10 tflO M tfl* M . . <0 Ot 00 Ot H w at o w W W H " « 00 •fc O H H 01 00 W . . to to -4-4 W « at OM M rr«^ Ot fr tfl • M H O W H « « tfl Ot H W -4 « o oo tfi at HH H O 0 • tfi o at w ggq 5 e Ot M M O Ot -4 . O 10 M Ot »H W 00 » o • w «fc H O M H <0 «0 Ot * H «0 tfl* •fc tfl . . IOtt-4 c£ O 00 Ot M M£? »>40 w 10 0 • tfl M ot • Ot VI » H •h «h HO «o at -4 ot • 1 1 M M M -4H i 00* H «0 ao M H W 10 HO W M H ^ «4 ^ OB ^ W C H H H HH w w » »» H HH i i i e H •* 1 1 1 1 1 1 -4-4 -4 -4 00 at * in u ot ot ao 1 -4« -4 -4 10 1 W 00 O «4 tfl tfl tfl «h *> tfl «4 W MI0 «O tfl W M MM M M tfl* W M H • • C H H W H W Ot tfl » H H M H H * -4 o et «fc H H H H H in in ot ot ot C H H H M w in ot M • HM W • «0 H tflo at 0 O -4 -4 -4 -4 -4 Ot »»4 Ot -4 -i ot w 10 at •.OtOtOtH H MH H H H O 10 »-4 Ot • HH HH H -4 M M » -4 H H HH H H H HMM -400 WOM tfl tfl M 10 00 W 10 «0 M tfl • H H* • 10 tfl »-4 00 O 00 0 H 00 00 W H H at H-4 H H H O Ot 10 10 H OO H HHH H in * w M H • • • • • H H H M 10 ao ot -J in * H HHH H W W *> tfl tfl MM M » M M M M M «fc MM »»4 O HH HH M OM W tfl tfl 000000 10 10 H<0 -4O «k H HM H H W » H •» at HHHM at «0 otot ot ^4 •- * E J? « J IT w •* • rr ! H • t A • ••M Q & IHWI0-4M 00 » Q t u •* • ^ ** HO * MMHMM W W W tfl » H Q _ 8 H S J" § • • _ w S Ii »s. 00 W IO W 10 O «k M «4 IO Z • 8 r Jd «- 9 •» r* n B * rr HHHHH HHHHH M H *J — ' OHHMM M W » W tfl JB Q •< ° Q Si H HQ «o M ^ w» T • • »< ot c-i * tfl K P M HHHM HMHHH ^ H4 10 H H W M *J H M O O K gj w in 5 ** g s 8 H M no D p t0WM»4-»] -4000t->]aO fc Q I * w ao* enat«0-4tfi » Q » H M S w H H H W 00 M tfl «4 *S «4 «4 *S 00 «4 K 10 4 w inot vi H in M ot K «J | g tfi 1 . s i srcl M| 1 1 S i M&P i e o w i S5 5 " o S • H-S S 81 "1 08 1 ! ° 1 »*B ""•^"S.B'I SS "fff* ^•rr HW i P <• . •*• 8 £M fi H i [it § ^ISS J§ 8 S g ', |»" g e.»<*>pa aji 5 i tr < H 1 BS»B •• • ' • * •*• S ^2« 8 I: ? a P 2 ^.s ^ M! o & M ^ f * - °t - g S*| ? , ^ i § g p. egg - " s ff8 i d 1 » H : ?r "• 1 S » I'd O "• 1 • >1 W W JB H H ! « ^SZ.S'B •< • S • 2 w ff 1^ 8 » "« . & o o a rrv«4 * QP ' • § • 2 — p * o y e t t m & i fi H ft & ft oo > o 3 * jrfi H« IT « ° - «g.a i • • K f ot o n Mfvpitfi • & ^a-f ^r s 3 8 1 a- ^ S iriitfiio • ?i — o w i«|EHMtrrij • * • «. er oES-'Oit .*M P ^fntll^^^iip ri^H 2 S3 p. ftM . JT " .H/ : ff"P ff rr S ? ^^ & Q "8| |« B- Q S q?S S3 BUR |9 1 < • 0 H*3 ? | |«j :^ a ? i ffS| !- Ii * a * a i C-H- 5- e -5K S? S B s - go rB* - < - wl , H » ca Old 5 ^ i ?8 : 1 1 Ip 7 L!U ^IL f 5" 1 O!M 5 !SC- "? & " " ^^S e 6 ?^ ?r B 8, S &&S H-QiQi^ilB Q H> 0 II W C HW 1 O O WU.O & CftS -• • £ B * g w 5 - o o pa o a tn£. ^. tf M • n> p-o* HI< M OP i »H » in ntrr > ot wi wi« M ot • ... .. .. .. ..... ..... ..... ..... q -400OMHW* OtfrH O* 00 Ot tfl -4 -4 Ot M at M H O «0 00 -4 -4 00 «0 00 Ot «fc W W W M Q •§• d 1 0 rr . i HP- tfifr w • • • • M H O fr *> «• «• -J MOO w M tfi «J oo «fc HH t M M I 287 RIO GRANDS DB LOIZA BASIN 50061800 RIO CANOVAKAS NEAR CAMPO RICO, PR—Continued HATER QOALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR DATE TIME OCT. 04 1512 NOV. 08 1202 DEC. 14 1430 JAN. 23 1146 FEB. 28 1037 MAR. 26 1415 STRBAMFLOW, INSTANTANEOUS (CFS) 28.6 19 19.1 16.4 10.4 42.9 SPECIFIC CON- TEMPBRA- DUCTANCB TURB (UMHOS) (DBG C) DATE TIME 150 206 208 203 254 205 27.0 26.0 25.5 22.5 22.0 25.0 APR. 17 1348 HAY 23 1053 JUN. 13 1443 JUL. 17 1158 AUG. 16 0924 SEP. 20 0959 STRBAMFLOW, INSTANTANEOUS (CFS) 9.84 9.94 6.78 5.24 4.32 8.72 SPECIFIC CON- DUCTANCE (UMHOS) 200 200 235 250 290 280 TEMPERA- TURE (DBG C) 28.5 27.0 30.5 28.0 27.5 26.5 288 THIS PAGE WAS LEFT BLANK INTENTIONALLY EXPLANATION !L A0670 SURFACE-WATER STATION AND NUMBER Y°725 QUALITY-OF-WATER STATION AND NUMBER 0123456 1234 Figure 20.~Northeastem river basins the Rio Herrera to Rio Anton Ruiz basins. 290 RIO HSPIRITU SANTO BASIN 50063440 QUBBRADA SONADORA HEAR KL VERDE, PR LOCATION.—Lat 18°19'24", long 65°49'03", Hydrologic Unit 21010005, in Caribbean National Forest, at El Yunque, 0.6 mi (1.0 km) upstream from Rio Bspfritu Santo, 0.2 mi (0.3 km) upstream from Highway 186, and about 1.2 mi (1.9 km) south of El Verde. DRAIHAGB AREA.—1.01 mi* (2.62 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—March 1983 to current year. GAGE.—Hater-stage recorder and creat-stage gage. Elevation of gage im 1,230 ft (375 m), from topographic map. REMARKS.—Records poor. AVERAGE DISCHARGE.—8 years (1984-91), 7.12 ftVs (0.202 mVs), 95.73 in/yr (2,432 mm/yr), 5,160 acre-ft/yr (6.36 hmVyr). EXTREMES FOR PERIOD OF RECORD.—Maximum discharge, 2,230 ft'/s (63.2 •?/•), Dec. 7, 1987, gage height, 9.42 ft (2.871 m) from rating curve extended above 20 ftVs (0.57 mVs) on basis of step-backwater analysis; minimum discharge, 0.10 ft3/* (0.001 mVs), Aug. 8-10, 15. EXTREMES FOR CURRENT YEAR.—Peak discharges greater than base discharge of 500 ftVs (14.2 •?/•) and maximum (*) i Discharge Gage height Discharge Gage height Date Time (ftVs) (m1/.) (ft) (m) Date Time (ftVs) (•?/•) (ft) (m) Oct. 7 1715 *440 12.5 *6.91 2.106 Minimum daily discharge, 0.10 ftVs (0.001 mVs) , Aug. 8-10, 15. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN ' FEE MAR APR MAY JUN JUL AUG SEP 1 1.7 2 .41 3 2.4 4 3.6 5 6.0 6 1.7 7 28 8 4.8 9 1.9 10 9.8 11 20 12 1.5 13 .90 14 .64 15 .50 • 16 22 17 2.5 18 10 19 4.5 20 2.2 21 33 22 1.9 23 1.0 24 10 25 21 26 30 27 4.7 28 8.4 29 5.4 30 7.3 31 1.7 TOTAL 249.45 MEAN 8.05 MAX 33 MIN .41 AC-FT 495 CFSM 7 . 97 IN. 9.19 CAL YR 1990 WTR YR 1991 1.1 .87 .70 .65 3.3 .99 1.7 .80 .41 .74 .46 .39 .34 .33 .32 6.2 1.8 .52 .35 .33 6.0 5.7 2.4 .49 .37 2.9 7.3 1.8 5.9 19—— 74.16 2.47 19 .32 147 2.45 2.73 TOTAL 2713 TOTAL 1626 10 11 31 7.2 3.4 1.1 .73 .55 1.3 .64 .42 1.1 6.4 3.1 1.9 8.2 1.5 .56 .66 .43 .41 1.8 4.4 1.2 .50 .38 12 9.5 41 24 54 240.38 7.75 54 .38 477 7.68 8.85 .63 MEAN .88 MEAN 19 9.1 5.1 3.7 8.0 14 3.4 5.1 6.5 14 8.8 3.4 2.0 3.0 4.2 2.4 1.1 .74 .56 .50 .46 .45 .43 .43 .42 .41 .40 .39 .38 .37 11 129.74 4.19 19 .37 257 4.14 4.78 7.43 MAX 4.46 MAX 2.6 .80 3.2 3.9 .52 14 .91 .41 .39 .37 1.1 .38 .39 .41 .52 .41 .41 30 22 27 7.7 5.1 5.8 10 7.3 3.7 1.8 1.8 —— —— —— 152 . 92 5.46 30 .37 303 5.41 5.63 91 MIN 54 MIN 1.8 8.5 10 4.5 5.6 4.5 1.9 2.1 1.4 1.0 2.3 1.5 1.3 3.3 1.0 .72 .59 19 9.4 1.5 1.0 46 5.7 2.8 2.0 1.6 1.4 1.1 .89 .79 .71 145.90 4.71 46 .59 289 4.66 5.37 4.4 1.8 7.1 2.6 .95 .79 1.6 27 3.6 4.8 7.9 14 18 17 17 7.8 3.7 5.2 2.7 2.0 1.7 1.6 1.4 1.2 2.3 4.4 1.6 1.1 .94 .83 —— 167.01 5.57 27 .79 331 5.51 6.15 .32 AC-FT 5380 .10 AC-FT 3230 1.1 .96 .87 7.6 .87 7.7 2.0 22 5.8 2.2 1.7 20 4.3 3.3 2.1 .99 .66 .45 2.1 4.8 1.8 3.8 .63 .34 21 1.9 1.5 .79 .58 .44 .38 124 . 66 4.02 22 .34 247 3.98 4.59 CFSM 7.36 CFSM 4.41 .32 .26 e.25 e.24 3.8 1.8 2.5 2.9 3.8 .49 11 7.2 1.0 .53 .41 .30 .23 .21 .25 .30 3.0 .86 2.9 .75 .27 e.24 1.6 .55 .87 16—— 64.83 2.16 16 .21 129 2.14 2.39 IN. 99 IN. 59 13 1.8 1.1 1.3 .49 .33 1.0 .59 .25 .18 e.16 e.15 e.14 e.14 15 24 1.4 .56 .37 .35 .24 .20 e.19 3.0 .58 .19 .76 .68 .87 2.3 1.8 73.12 2.36 24 .14 145 2.34 2.69 .95 .92 .31 .51 2.3 .27 .14 .13 .11 e.10 e.10 e.10 e.ll e.12 .23 e.ll e.10 e.13 7.0 5.2 .84 1.5 8.3 32 4.4 1.5 1.1 .90 28 5.1 1.6 1.1 .95 104.36 3.37 32 .10 207 3.33 3.84 .84 .73 .62 .54 .48 .49 1.1 .60 2.4 1.6 3.4 .83 .48 .38 .31 .42 2.6 1.9 .92 .41 1.5 19 3.2 1.6 2.9 2.6 22 3.5 13 10—— 100.35 3.34 22 .31 199 3.31 3.70 Estimated 291 RIO B8PIRITU SANTO BASIN 50063440 QOBBRADA SONADORA NEAR EL VERDE, PR—Continued WATER QUALITY RECORDS PERIOD Of RECORD.--WATBR YEARS APRIL 1983 TO CURRENT YEAR DATS TIME OCT. NOV. DEC. JAM. FEB. 03 1135 07 1401 13 1232 IS 1325 21 1448 STRBAMFLOW, ZttSTANTANBOUS (Cfg) S.SO .67 1.29 1.85 7.10 SPECIFIC COH- TEMPERA- DUCTANCB TURB (UMH08) (DEC C) DATE TIME MAR. 28 1307 56 57 78 52 52 60 24.0 24.0 21.0 20.5 22.5 22.5 ABR. 30 1233 MAY 22 1234 JDN. 14 1211 JDL. 18 1057 AUG. 14 1329 SBP. 15 1205 8TRBAMFLOM, INSTANTANEOUS (CFS) .83 10.2 .52 .59 1.39 2.04 SPECIFIC CON- DUCTANCE (UMHO8) 62 50 60 55 64 70 TEMPERA- TURE (DBO C) 24.0 23.5 24.5 24.5 25.5 23.5 i J i. * O C* O rH C* I ODtectO • O rH H IA e e e «iAi0iAiA <« u>» r» IA o A H o A » « t» t» •* o t» IA o IA OHHHH rHHHHH HOOOO OOHHO O O H rH O rH H O O O O ft H >O • PI 10 t» ft ft ft C*H 2J J 9 ast • j- ° ° 5 ft • *» • • I S 3 •H "I H >, IA PI PI Hi0( rHf«PI»» €»«IAM» Q I«0H *00 W1 * W 4 •J M M W UI W II H H •J 9\ e e II W ^G M M W H • • H H 0> O ON H tfl H 0> • W W to O -Oto H » M ll Kl MMHMM 10 «l tfl H W W «J U ot H « « *i M e w H ! eWMW. W A M M M M M MMMMM M W W W UI tfl tfl * tfl O - - - ^IHMMWW »vi vi ON -o to o w w H uu ON «JON •J W U H M C4 HW >> HH Z 10 W w e RR as as ,H •J * e e *1 M H H • M H W O 10 WO tfl »» M W H • • H w me •4 H »H M • 10 » H O» I0» W 1 1 1 1 1 1 MMW 1 1 i |d MH MH £MHH e w tftvt«d w HWH M M W H Mfc M H 10 M H «0 *> M HH Ctfl I0HM tfl H> to O H 91 *>HH 10 AM* tfl M M M WOt MM H MH •O UOA O W M M M M •» O M M A ^1 tfl H M M M W *1 O M M H M Ol tfl W tfl 10 H* M O «I M W ^ ^ M W ^1 ^ U U UI * M W H • •WHWHI K*H Otfl*HO>. O> IHHHHM HHHHH H M W M A M tfl to O> W tOONOWWWO I WU»0tM WtflOlMON «4 O ^ O> W -4UI-4Otfl UI fc M U M > • » H W M M tfl O H> to • O ...... HMOWHO* »»tfl^l«k« MM H M t H H K» M UMW^H »WU» t* «k p (^ W « U O W UI U *» H M «U0t MO »M« 0» UI 0t K* W*0tfi«~Hi"«" •• • WUOO-OUOI ON W H H H UI H •!>*•• * *fl 00 «J « W \fl W -4 -4 • • W«0 • MOMM K»W-a«» >• • U M^ I MUM M «J toOtWtflM MHMHH H H H H H H H H • • tfl WH ON to IH^iMMM H ON ON tfl * OMOtOH H»«HW> U O tfl * tfl • • I •> •OMOOMOtO I tO* RIO E8PIRITU SANTO BASIN 50063800 RIO BSPIRXTD SANTO NBAR RIO GRANDB, PR—Continued WATER-QUALITY RECORDS PERIOD or RECORD.—Water years 1958, 1961-66, 1968 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SBPTBMBER 1991 295 DATE NOV 1990 02... DEC 04... PEB 1991 07... APR 05... JON 06... AUG 05... TIME 1245 0910 0835 0810 1010 1300 DIS- CHARGE, INST. CUBIC PBBT PER SECOND 31 63 42 17 23 7.5 SPB- CIPIC CON- DUCT- ANCE (US/CM) 98 64 67 103 79 110 PH (STAND- ARD UNITS) 7.9 6.8 7.0 6.9 7.5 7.9 TEMPER- ATURE WATER (DBG C) 26.0 21.5 19.5 23.5 25.5 30.5 TUR- BID- ITY (NTU) 2.5 13 1.5 2.5 4.4 1.5 OXYGEN, DIS- SOLVED (MQ/L) 8.2 8.9 9.2 8.3 8.2 7.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 100 99 100 97 100 100 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 17 23 11 10 <10 COLI- PORM, PBCAL, 0.45 UM-MF (COLS./ 100 ML) 4200 K110 K1100 47000 K1800 10 STREP- TOCOCCI PBCAL, (COLS. PER 100 ML) HI 60 K10 3700 380 3500 40 DATE NOV 1990 02... DEC 04... PEB 1991 07... APR 05... JON 06... AUG 05... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MQ/L TOT PLD SOLVED AS MG/L AS (MQ/L CACO3) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MQ/L AS CA) AS MO) AS NA) 31 0 6.9 3.4 7.6 33 1 7.3 3.6 8.4 36 1 7.5 4.1 8.3 SODIUM AD- SORP- TION RATIO ALKA- POTAS- UNITY CHLO- SIUM, WAT WH SULPATE RIDE, DIS- TOT PET SULPIDB DIS- DIS- SOLVED PIBLD TOTAL SOLVED SOLVED (MG/L MG/L AS (MQ/L (MG/L (MQ/L AS K) CAC03 0.6 0.60 0.6 0.80 0.6 0.70 34 16 20 33 23 43 AS S) AS S04) AS CL) <0.5 <0.5 1.9 11 2.0 11 1.9 11 DATE NOV 1990 02... DEC 04... PEB 1991 07... APR 05... JUN 06... AUG 05... PLUO- RIDB, DIS- SOLVED (MG/L AS P) <0.10 — — <0.10 — <0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 18 — — 15 — 19 SOLIDS, SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 70 — — 68 -- 78 RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS SU8- TOTAL TOTAL TOTAL TOTAL TOTAL PER PBNDBD (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 5.75 3.19 1.59 <1 3 13 1 3 <1 0.09 0.19 0.19 0.043 0.058 0.049 0.010 0.010 0.010 0.010 0.010 0.010 0.100 0.200 0.200 0.053 0.068 0.050 0.030 0.060 0.020 0.030 0.030 0.020 0.27 0.24 0.68 0.27 — 0.38 K * non-ideal count 296 RIO BSPIRITD SANTO BASIN 50063800 RIO BSPIRITD SANTO NEAR RIO ORANDB, PR--Continued WATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 02... DEC 04... FEB 1991 07... APR 05... JUN 06... AUG 05... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.30 0.70 0.30 <0.20 0.40 NITRO- GEN, TOTAL (MG/L AS N) 0.40 0.50 0.90 0.35 — 0.45 NITRO- GEN, TOTAL (MG/L AS N03) 1.8 2.2 4.0 1.6 — 2.0 PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) <0.010 <1 0.050 0.050 0.010 <1 0.030 0.030 BARIUM, BORON, TOTAL TOTAL RBCOV- RECOV- ERABLE ERABLE (UG/L (UG/L AS BA) AS B) <100 <10 — — <100 <10 — — CHRO- CADMIDM MIUM, COPPER, TOTAL TOTAL TOTAL RBCOV- RBCOV- RECOV- ERABLE ERABLE ERABLE (UG/L (UG/L (UG/L AS CD) AS CR) AS CU) <1 1 10 — — <1 <1 10 — — DATE NOV 1990 02... DEC 04... FEB 1991 07... APR 05... JUN 06... AUG 05... IRON, TOTAL RECOV- ERABLE (UG/L AS FE) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) KING, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 240 270 35 <0.10 <0.10 <0.010 <0.010 0.03 0.02 RIO BSPIRITU SANTO BASIN 50064200 RIO GRANDS NEAR EL VBRDB, PR 297 LOCATION.—Lat 18«20'54", long 65«50'30", Bydrologic Unit 21010005, on left bank 250 ft (7.6 m) upstream side of bridge at Bwy 960, 0.05 mi (0.08 km) southwest of junction of Highways 956 and 960, 1.1 mi (1.8 km) west of Bl Verde, and 2.7 mi (4.3 km) south of Rio Qrande. DRAINAGE ARBA.—7.31 mi» (18.93 km* ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—May 1967 to December 1970, January 1972 to September 1982, August 1990 to current year. GAGE.—Water-stage recorder. Elevation of gage is 131 ft (40 m), from topographic map. REMARKS.—Records fair. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--14 years (1968-70, 1973-82, 1991), 45.4 ft3/" (1.286 m3/s), 84.34 in/yr, (2,142 mm/yr), 32,890 acre-ft/yr (40.4 hmVyr); median of yearly mean discharges, 39 ft3/" (1.10 m3/s), 28,200 acre-ft/yr (35 hmVyr). EXTREMES FOR PERIOD OF RECORD.—Maximum discharge, 17,400 ftVs (493 m3/s), Sept. 16, 1975, gage height, 15.5 ft (4.724 m), but may have been exceeded by flood of Dec. 9, 1975, from rating curve extended above 100 ftj/s (2.83 mVs) on basis of slope-area measurement of peak flow, datum then in use; minimum discharge, 1.6 ftj/s (0.045 m*/s) Mar. 13, 1977. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 3,000 ft3/s (85.0 •?/•) and maximum (*) i Date Time Discharge (ft3/s) (m3/s) Gage height (ft) (m) Date Time Oct. 16 1630 *4,100 116 *11.62 3.542 Minimum discharge, 2.1 ftVs (0.059 m3/s), Aug. 16. Discharge (ftVs) (mVs) Gage height (ft) (m) DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. 23 11 45 59 64 22 151 117 42 62 107 28 22 19 21 261 65 51 58 36 182 40 29 44 146 134 65 81 55 75 33 2148 69.3 261 11 4260 9.48 10.93 28 25 22 21 24 23 34 24 18 17 16 16 15 14 14 30 18 16 14 19 16 70 24 17 17 38 85 26 49 68 —— 818 27.3 85 14 1620 3.73 4.16 85 73 172 63 37 24 21 19 21 19 17 17 20 24 23 36 20 16 15 13 13 21 30 17 14 12 61 83 224 122 250 1582 51.0 250 12 3140 6.98 8.05 147 68 49 47 64 79 40 46 68 78 64 37 33 32 31 34 25 22 21 20 19 17 17 17 16 15 15 14 14 14 25 1188 38.3 147 14 2360 5.24 6.05 28 18 26 18 14 44 22 14 12 12 38 18 19 13 12 11 11 92 99 110 41 28 30 23 24 23 15 14 —— —— —— 829 29.6 110 11 1640 4.05 4.22 14 19 19 37 30 26 17 15 15 12 12 12 11 11 10 9.9 9.7 23 19 11 9.8 111 25 13 11 11 10 9.4 8.7 8.7 8.7 558.9 18.0 111 8.7 1110 2.47 2.84 9.0 9.1 9.0 9.7 8.6 7.8 8.5 57 20 12 11 29 48 55 26 26 12 11 9.7 9.1 8.8 8.7 8.8 8.6 8.2 12 8.5 7.8 7.6 7.3 —— 473.8 15.8 57 7.3 940 2.16 2.41 8.3 8.2 7.5 10 8.8 11 12 50 20 15 10 78 22 17 23 16 11 13 18 24 12 15 12 9.2 39 17 15 9.9 8.6 8.0 7.7 536.2 17.3 78 7.5 1060 2.37 2.73 7.9 9.8 8.3 7.0 8.0 11 9.2 7.5 9.4 6.8 6.4 20 9.5 7.0 11 6.5 5.9 5.6 5.6 5.2 30 14 14 11 6.9 6.0 12 11 10 28 310.5 10.3 30 5.2 616 1.42 1.58 41 14 8.8 11 7.4 6.1 6.Q 6.0 5.5 5.4 5.5 5.4 5.1 4.9 13 53 13 7.4 5.9 5.7 5.2 5.0 4.8 4.8 4.9 4.2 5.0 4.3 3.8 4.0 4.5 280.6 9.05 53 3.8 557 1.24 1.43 4.0 3.5 3.5 3.3 3.1 3.0 3.1 2.8 2.8 2.6 2.6 2.5 2.7 2.5 2.2 2.3 2.8 9.2 7.3 5.4 15 39 15 4.5 3.3 3.0 43 23 5.3 3.6 3.1 229.0 7.39 43 2.2 454 1.01 1.17 2.9 2.6 2.7 2.7 2.6 2.6 4.1 4.4 9.8 8.2 5.5 4.7 3.5 2.7 2.6 2.7 3.9 5.2 3.0 2.5 5.6 79 12 6.0 5.6 8.9 135 30 57 36 —— 454.0 15.1 13S 2.5 901 2.07 2.31 WTR YR 1991 TOTAL 9408.0 MEAN 25.8 MAX 261 MIN 2.2 AC-FT 18660 CFSM 3.53 IN. 47.88 298 RIO BSPIRITU SANTO BA8IM 50064200 RIO ORAHDB HBAR EL VBRDB, PR--Continued HATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1990 TO SEPTEMBER 1991 STRBAMFLOW, SPECIFIC CON- TBMPERA- DATB TUB INSTANTANEOUS DUCTANCB TORE (CFS) (UMHOS) (DBO C) OCT. 04 1111 NOV. 07 1141 DEC. 13 0948 FEB. 21 1030 MAR. 28 1115 47.2 18.4 16.4 38.2 9.10 80 129 130 90 96 26.0 26.5 23.5 24.0 25.0 DATE TIME APR. 17 1059 MAY 16 1105 JUN. 13 1219 001.. 17 1349 AUO. 13 1615 STRBAMFLOW, INSTANTANEOUS (CFS) 12.6 15.7 9.09 11.4 2.97 SPECIFIC CON- DUCTANCE (UMHOS) 107 105 110 100 166 TEMPERA TURB (DBO C) 25.0 27.5 29.5 28.5 32.5 RIO MAMBYBS BASIN 500«S500 RIO MAMEYBS NKAR 8ABANA, PR 299 LOCATION.--Lat 18«19'46", long 65«45'04 <> , Hydrologic Unit 21010005, on left bank, at bridge on Highway 908, 1,4 Hi (2,3 km) wast of Sabana, 2.0 mi (3.2 km) downstream from Rio te la Ulna, and 3.2 •! (5.1 km) southaaat of Mameyes. DRAINAGE AREA.--6.08 mi» (17.82 km*). NATBR-DISCRARGR RECORDS PERIOD OP RBCORD.-'August 1967 to December 1973. JUne 1903 to currant yaar. OAQB.--Watar-stag* recorder and crest-stage gaga. Rlavation of gaga !• 275 ft (04 m), from topographic map. RBHARKS.—Raeorda fair •xeapt those for estimated dally discharge*, which ara poor. Gage-height and pracipitation aatalllta telemetry at atatlon. AVBRAOB DISCHAR08.--14 years (1968-73, 1984-91), 57.7 ft*/" (1.634 mV«), 113.89 In/yr (2,093 mm/yr), 41,800 acra-ft/yr (51.5 hmVyr)j median of yearly mean discharges, 59 ft'/» (1.67 •?/•), 42,700 acra-ft/yr (53 hmVyr). EXTREMES POR PERIOD OP RECORD.--Maximum discharge, 20,500 ft1/* (589 •?/•), Sept. 10, 1909, ga0« height, 13.19 ft (4.920 m), from rating curve extended above 1,000 ft1/* (51.9 **/•) on basis of flope-area measurement of peak flow; minimum discharge, 5.1 ft1/* (9.144 mVa), Apr. 9, 9, 1970. EXTREMES POR CURRENT YEAR.--Peak discharges greater than base discharge of 4,090 ftVs (113 mVs) and maximum (*) i Data Oct. 7 Ally 1 Time 1739 9345 7,059 5,589 299 150 Gage height (ft) (m) 9.03 2,752 8.34 2.542 Date Aug. 22 Discharge Time (ftV«) (m»/a) 1615 *7,140 202 Oage height (ft) (m) *9.07 2.764 Minimum discharge, 9.0 ft1/" (9.255 mVa), Apr. 39, May 1. DISCHARGE, CUBIC PBBT PER SECOND, WATER YEAR OCTOBER 1999 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT MOV DBG PBB MAR APR MAY JON JDL ADO SEP 1 39 2 34 3 69 4 54 5 44 6 39 7 214 0 69 9 55 19 194 11 149 12 46 13 37 14 31 15 32 16 153 17 89 19 163 19 113 29 61 21 187 22 69 23 44 24 59 25 192 26 163 27 199 29 11$ 29 92 39 139 31 5| TOTAL 1699 MEAN 86.9 MAX 214 Mm 39 AC-PT 5349 CP8M 12.6 IN. 14.54 CAL YR 1999 WTR YR 1991 44 37 31 65 74 44 48 36 29 32 28 25 23 22 24 66 47 29 22 28 45 •9 32 2f 27 48 63 35 75 167 — « 1361 4S.« 167 22 2798 6.59 7.36 TOTAL 21974. TOTAL 17195, 143 66 32| •359 •4f •35 •31 •29 •36 •31 •39 •69 44 98 44 52 34 24 23 21 29 26 35 27 29 19 46 92 194 135 241 2262 73.9 359 18 4499 10.6 12.23 0 MEAN 2 MBAM 145 94 69 63 61 07 59 66 57 107 ft 49 37 36 46 37 29 26 24 23 22 21 21 29 19 18 17 17 16 16 79 1461 47.1 145 16 2999 6.95 7.99 69.2 MAX 46.9 MAX 34 21 48 189 46 169 49 29 25 23 26 44 37 26 27 21 19 114 194 111 43 39 34 7« 51 31 21 21 —— — - --- 1469 52,1 189 19 2909 7.59 7,89 945 MIN 359 MPI 19 32 45 39 41 39 25 34 24 29 28 22 23 36 29 16 14 159 74 21 19 192 51 27 24 21 29 18 17 1§ 15 1139 36.7 192 14 9169 5.34 6.16 23 19 18 19 14 13 24 195 26 22 34 36 68 82 61 38 39 27 17 14 13 19 14 11 19 26 13 11 19 9,2 —— : 824.2 27.5 195 9.| 1638 3,99 4.46 14.9 AC-PT 43599 9.2 AC-PT 33939 22 12 19 42 15 50 42 193 49 32 41 138 27 21 21 15 15 18 23 48 59 116 39 22 59 23 21 29 19 29 29 1153 37.2 139 12 2299 5.41 6.23 CPSM 9.75 CPSM 6.91 35 29 17 17 43 36 39 28 49 19 71 «7 24 23 22 19 18 22 39 25 54 32 66 39 31 If 33 49 31 IfS TT- 1114 37.1 185 17 2219 5.49 6.92 Pi- Pi- •31| •38 •33 39 27 23 22 22 21 19 19 19 17 16 69 99 23 19 18 19 16 *7 17 29 •!* •21 25 29 22 33 32 1194 35.6 314 16 2199 5.19 5.97 118.91 92.49 IP 17 33 20 27 22 19 10 18 17 17 17 3? 17 18 10 50 07 40 58 1« H3 79 I* ?l 38 113 55 26 31 23 1390 44.8 313 17 2760 6.52 7.52 20 19 10 IS 15 15 17 •18 •47 •38 •26 •23 10 15 I* 17 It 22 18 16 35 97 40 32 52 54 140 52 111 103 TTT 1147 38.2 148 14 2200 5.56 6.20 • Estimated 300 RIO MAMBYES BASIN 50065500 RIO MAMEYBS NEAR SABANA, PR—Continued WATBR QUAIJTY RECORDS PERIOD OF KBCORD.—WATBR YBARS JUNE 1983 TO CURRENT YBAR DATE Til OCT. 02 1346 NOV. 06 1625 DBC. 12 1336 JAN. 18 1207 FEB. 13 1428 MAR. 20 1609 STRBAMFLOW, INSTANTANEOUS (CFS) 51.8 37.1 55.8 27.8 30.8 20.4 SPECIFIC CON- DUCTANCE (UMHOS) 95 92 104 75 96 96 TEMPERA TURB (DBG C) 26.0 26.5 23.0 22.5 23.0 26.0 DATE TIME APR. 16 1439 MAY 21 1638 JDN. 18 1345 JDL. 11 1512 13 1302 15 1300 AUG. SEP. STRBAMFLOW, INSTANTANEOUS (CFS) 35.2 78.2 23.8 19.7 22.4 21.1 SPECIFIC CON- TBMPBRA- DUCTANCB TURB (UMHOS) (DBG C) 104 90 110 120 124 100 25.0 26.5 28.0 28.0 28.5 27.5 RIO 8ABANA BASIN 50067000 RIO SABAKA AT SAHARA, PR 301 LOCATION.—L»t 18»19'52", long 65»43'52", Hydrologic Unit 21010005, on right bank along Highway 988, 0.3 Mi (0.5 km) north of Junction of Highway* 988 and 983 in Sabana, and 3.3 mi (5.3 km) south of luguillo. DRAINAGE AREA.—3.96 mi» (10.26km»). HATER-DISCHARGE RECORDS PERIOD OP RBCORD.—October 1979 to current year. OAOB.—Water-stag* recorder and crest-stage gage. Elevation of gage is 260 ft (80 a), from topographic Bap. REMARKS.—Records fair except those for estimated daily discharges, which are poor. AVERAGE DISCHARGE.—12 years (1980-91), 19.6 ftVs (0.555 mVs), 67.21 in/yr (1,707 mm/yr), 14,200 acre-ft/yr (17.5 hmVyr)* Median of yearly mean discharges, 20 ftVs (0.57 mVs), 14,500 acre-ft/yr (18 hmVyr). EXTREMES FOR PERIOD OF RBCORD.--Maximum discharge, 9,010 ftVs (255 •?/•), Apr. 21, 1983, gage height, 19.35 ft (5.898 m), from floodmark, from rating curve extended above 200 ft3/* (5.66 •?/•) on basis of step-backwater analysis and slope-area measurement) minimum discharge, 0.86 ft3/* (0.024 •?/•), Apr. 17, 1983. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 1,500 ft3/* (42.5 •?/•) and maximum (*)« Date Oct. 7 Oct. 16 Tims 1730 1200 Discharge (ftVs) (mVs) 2,310 1,660 65.4 47.0 Gage height (ft) (m) 13.34 4.066 12.39 3.776 Date June 30 Aug. 22 Time 1100 1615 Discharge (ftVs) (mVs) Oage height (ft) (m) *4,520 2,750 128 77.9 *15.80 13.90 4.816 4.237 Minimum discharge, 1.4 ftVs (0.040 mVs), Apr. 29, 30, May 1, 2. DISCHARGE, CUBIC FBBT PER SECOND, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT MOV DBC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 3.9 15 21 9.8 5.6 14 137 22 28 72 81 13 9.4 8.2 7.3 156 58 157 57 25 109 25 33 31 45 65 24 21 21 e52 e21 1347.2 43.5 157 3.9 2670 11.0 12.66 1990 1991 e!8 e!6 e!5 e!4 e30 e!8 17 14 12 11 11 10 10 10 10 13 12 11 8.8 20 18 13 9.3 8.7 7.7 8.9 10 8.5 13 91—— 468.9 15.6 91 7.7 930 3.95 4.40 TOTAL 7604. TOTAL 6185. 89 16 115 23 16 12 11 11 13 11 9.1 13 9.1 67 13 8.7 8.7 .9 .6 .0 .0 .6 .9 .3 .8 .4 .3 21 148 50 195 920.4 29.7 195 4.4 1830 7.50 8.65 0 MEAN 9 MEAN 50 26 13 e!6 e!9 e25 e!7 e!9 e!7 e31 e26 e!5 ell elO e!3 ell e9.0 7.2 7.0 6.8 6.4 5.6 5.5 5.5 5.1 .7 .5 .3 .4 .0 12 411.0 13.3 50 4.0 815 3.35 3.86 20.8 MAX 16.9 MAX 7.9 4.5 6.7 26 8.4 29 8.6 4.5 e4.3 e4.1 e4.4 e7.6 e6.6 5.3 6.2 3.9 3.3 10 37 33 8.7 5.2 4.9 15 10 8.7 5.1 7.0 —— 285.9 10.2 37 3.3 567 2.58 2.69 569 MIN 328 MIN 5.2 4.6 4.9 4.5 7.6 6.6 5.3 6.9 5.9 5.1 10 5.9 5.3 6.0 5.2 4.6 4.6 7.3 8.8 4.8 4.0 72 11 4.8 4.2 4.2 4.9 3.2 3.3 3.4 3.3 237.4 3 7.66 72 3.2 471 1.93 2.23 2.2 AC-FT 1.5 AC-FT 5.5 4.0 4.0 3.4 2.7 2.9 4.6 16 6.4 3.8 4.4 3.3 5.1 8.1 5.4 6.6 3.7 3.4 3.0 2.7 2.7 13 4.9 2.1 1.8 2.6 2.1 2.4 1.7 1.5 — - L33.8 4.46 16 1.5 265 1.13 1.26 15080 12270 2.0 1.8 5.1 8.4 2.6 7.9 21 55 5.8 9.6 4.6 148 7.5 4.1 3.8 3.5 8.4 11 4.4 8.8 45 135 10 5.5 7.0 4.6 3.5 3.3 2.9 2.8 2.9 545.8 17.6 148 1.8 1080 4.45 5.13 CFSM 5.26 CFSM 4.28 19 3.9 2.7 2.8 23 40 15 4.4 5.0 3.7 23 7.8 3.7 3.0 2.7 2.4 2.3 5.8 7.3 2.7 3.7 2.9 194.1 2.8 2.4 4.8 3.9 6.9 328 —— 558.7 18.6 328 2.3 1110 4.70 5.25 IN. 71. IN. 58. e80 e25 17 12 7.3 5.9 5.2 4.3 4.1 4.0 3.9 3.8 3.7 3.6 15 18 5.9 4.5 5.2 7.0 .5 .2 ,3 .8 .4 .1 .4 .2 7.1 4.6 8.5 292.5 9.44 80 3.6 580 2.38 2.75 43 11 4.9 4.8 9.0 10 9.6 6.3 5.6 5.5 5.0 4.8 4.9 5.3 5.5 5.0 8.3 8.9 22 36 9.3 31 49 226 25 7.3 5.7 5.0 62 247.6 6.0 5.9 625.2 20.2 226 4.8 1240 5.09 5.87 .7 .9 .5 .3 .3 .1 .0 3.8 13 9.8 5.6 4.9 4.2 4.0 3.7 4.0 13 4.8 3.9 3.5 4.5 15 6.6 5.4 7.6 18 99 19 32 43 —— 359.1 12.0 99 3.5 712 3.02 3.37 Estimated 302 RIO SABANA 50067000 RIO SABANA AT SABANA, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD,—WATER YEARS AUGUST 1981 TO CURRENT YEAR STRBAMFUnr, SPECIFIC CON- TEMPERA- DATE TINE INSTANTANEOUS DOCTANCJ TORE (CF8) (UMHOS) (DBG C) OCT. 02 1047 NOV. 06 1259 DEC. 11 1546 JAN. 17 1335 FEB. MAR. 13 104$ 21 17.6 16.7 7.52 6.41 12,f 4.56 110 103 130 90 93 90 26.0 27.5 24.9 24.5 23.0 25.Q STRRAMPLOW, SPECIFIC CON- TEMPERA- DATK TINE INSTANTANEOUS DOCTAJCB TORE (CFS) (UNH08) (DBQ C) APR. 16 1037 MAY 21 1433 OUN. 17 1428 JUL. 11 1050 AUG. 15 1510 SEP, 27 1526 8.55 6.40 2.35 3.71 7.31 314 96 120 130 122 120 74 34.5 28.0 30,0 27,0 28,0 26.0 IP H H «OIO «O IO H O iin Co- SS O -J «O A •• in o in •J hi EE A «O H •) hi M S B 23£ggg3 * fi-i SP «0>J>J hi • • M VIH A H «*IO M H H -J •J VIO A O« hi MMM hi H • • H H VIO Afchl H 0« -J «oo •• o« in H A •» Ui Ui VI H o VIH • in* • •»OO fc OMhl MMH hi . . IO H H W •»H hi H M« -J MO OO "Jhl H Ul UIM •» H • • VI M VIM H OMH O> -J « ino H winu hi hi MM MM H O«O « •>) A M H H Ot O >J Ul >J •» Ul-lhl M A * 1 1 -Jhl H hi M 1 UIO W hlhl •» M in « •>) M VIH HH H H UIH MM 00 1 1 1 1 | | H H M 1 1 1 A * •>) MMMMM in fchi MH H M H A A •>!•) A Ahl A A M HHMM hi •»««•» O H H H H H M •»« AH C H H H H •»&•»•» Ui •» UtM* hi MUI« fc MHH HH MM H Ul • 0 •» 10 H A«»in «o H H M MM IO-1 U Mhl H H H MM H H •• •• Ul K H H MM A* OIO MH AO H H H H H H H H in *» w MH M A hi fc UIO hi •» UIM •• MMMMM O H •»•»!• M MH M H M •>«««••• MMMM W A •> •>) «O O H H hi •• H •J A UIW •» H010 m -i A CHUI « w ino « in in hi hi •» -J A H •••>) UIM H H H MM •J «J •) O fc VI Mhl hi •» IOIO hi A •) H H M hi W M*>0 •» 0 in •• WMH K XZ2ZS S * « ou«> in Q •J O«hlfc < * £* & ?r 6 MH «O A e 8r SE 3 0 in o o !' j 10 •••• M * * § "" Hi Hfc ft -J «O - 00 hi »MU> A » • hi IO H VIM H ™ S S PB §* «-j 1 ^ g » •* M « w hi AMHM H O •.AOMxl B gj tr>< f vt^i H " ; r MM • ^* 523 VIA ££ 33 M •» «O O in o 0 M 0 0 QQ Mhl •J -J hlH titi SB X hi in •J O H hi hi m A HHH H H VlhIM* •. • • •» •» o •» H 10 in •J HHH M «O • • in JH A ^HgHH in in. H H H M 1 «* H •• UIH 1 • 1 -J H H H H H Ul« H W A •) A H M MUt •» H H AH H It H HH MH fr hi IO hi Ul M H M« hi •» JO •••••• MH H H H •) •>!» H H «O A •>)•>)•>) M M H MO hi hi A A •>) •• H H H H M OMUIfcH Mhl A M OOhl MIO H H Ul hi O MM o AO -IH K9 *••» --K-K g Ii S ^ a ' H H HH M < H O IO OM g 1 in 90 i D J ' e«ci 9 U 9 H ° H M AfcHH „ «* OUMOH i g OH K «>M >4 H H 0 inin H MMM hi M • • M •) •» «J «J • Vtfc* W • H hi M M hi O MMOVI U» O •) MH H M« • • «J VI M« H MIO W • A« • OH OUt O* « in HHH H -J ••HA ««M •• Mhl • IO • • hi «0hl UIH M IO hi hi H 1 IO •>! H •>) * 1 H H H H M hi Ul H H H Ul IO in •• wo -J «* •j A->)hl IO H 1 Mhl 0 Ul«* 1 H H MMhl 0 A-JM A H H H H H fcVB OH M H H*« A A •• «« A •>!•>! A^Min. hi «O H H H H W -J Ul M»1«IO •> H H H H Ul Mhl fc ht •J VI A A A H Ul A •• A MH A -J WIOM A H hi H MH hi Ul hi O A OH H H H M M •. VI^HH A~l«*l*l H H A hi A •J IO A H HHM I IO VB H VI-J Q i o 3 | A t Mhlfc AH « A >JH Ah» tJ I P * H H 10 10 MI/I »J f m >jui Q «eo-J € ij » i AW 9 u in S AM 3 0.0 ^ » ^ H ««0 OIO •J » H O -J H «0 «•• ht M H •» OM Ul O ?? ? r* rr Discharge Vs) («"/s) ( N>O ft If ^s F? £s ft ?? 3 1 r*ttw «^ • O — P» 1 P 5. 1?s «r &«• s fr § a 1 1 a5 R. — Peak discharges Q 2tt H | sr 2 oHi u % * i Br Ii •» ?S rs OM O K M^WM fca AM V?S £.• 2 8*8 !;*8 "2?8 H H D M «|H-{S ^fci i * * fit S36 & fft § £ | !? ? MM II*S *^ Q&C- aIs^ ^gin &H.B. S t,*^ a^«. B " «C» •«« w tt B.»wH B^« H-a • I H low Sj? lit |-8 ?&»• » S • H '"I* sir JjpM ft a o HSJI . m%° • 8 o rt J? >j Op .8 B*e ^•a Si w «iIi g° P L^ &I 1:§sr- !? » H S?- • «* » • 9*<~> «OH Hi VO ft M ^« '"- *«.•>. H« «o» ini? ^•o *.** * & inr"3 o*1 o^. °H • * ft W 9 -4 9 A • "• 41 •tf. i"< ^§E % A fc M* ts «». O M3s ' ? HI tts £*f a ft» lr" 2ft ^1 MB ?r Low flow affected a daily discharges M -ft °5 mn "-H. "If O M -? in'1 • « S? £i!^ £S B*s s f ° E. <0 B i! rmmm f r ipitati ii P 9n £1 H- S n i • • i A?* 5i? •4 era »|g er* jnftj VI B1 O .-. • • 1*1 *lf ?r* *-* H a V HHH -j. m % MH H •» W «*» -J •J • MH A <• o ft A SHJJ *s-~ H •• M*r yiKg VIO H» «• W *4H'C> in «* * 5& V I • H * * w _ A«B »' 1 «oi jjinp ~ t*a s"8 W-. • •• H 2 M § in w • VIM i*" }[ A r* Si A *• g1 8J % wot? n a o 1 i Its 1 1 & S t m **£• Q » SB * § *r fc| " P H S»S f ?* *?H* * * II"2 s n Ms 1 " U » A • «•» H ~> U»«4 W «JH * " **I § * -H* : tr 5»*s £ j "•.• B ' (Tot H &• •> W WM 0 1 Ki IS fat s if Hn-i IB Q. "W t* R MCft » f I rin « & 1 • M * o 1 i i ;§ * s H 3D r% O 16 H 0 •* I *" S f§ 1 S > o fsr • S L3 S % 1 er * li g 5& n Ot 81 Fa H HI s r- H HP S Hi 2 p* i •* i ** it i ve 1 8"* 5 * • fr* 0 • • »t M*! 304 RIO FAJARDO BASIN 50071000 RIO FAJARDO NEAR FAJARDO, PR—Continued HATER-QOALITY RECORDS PERIOD OF RECORD.—Hater years 1960 to current year. MATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 02... DEC 03... FBB 1991 05... APR 04... JON 04... ADO 06... TIME 1400 0930 0900 0855 0950 1135 DIS- CHARGE, INST. CUBIC FEET PER SECOND 70 298 35 13 9.0 7.0 SPE- CIFIC CON- DUCT- ANCE (US/CM) 112 93 91 135 130 130 PH (STAND- ARD UNITS) 8.1 6.8 7.1 6.9 7.1 8.2 TEMPER- ATURE HATER (DBG C) 28.5 23.5 21.5 25.0 26.5 30.0 TUR- BID- ITY (NTU) 7.0 95 3.5 5.9 0.90 1.0 OXYGEN, DIS- SOLVED (MG/L) 8.0 8.0 8.0 8.6 7.7 8.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 102 93 90 103 95 109 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 12 34 15 <10 <10 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2000 60000 380 K10 K590 K60 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 8600 37000 2100 K27 460 K190 DATE OCT 1990 02... DEC 03... FBB 1991 05... APR 04... JUN 04... AUG 06... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL NH HAT DI8- (MG/L TOT FLO SOLVED AS CAC03) CAC03 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DI8- DIS- SOLVED SOLVED (MG/L AS CA) AS MG) AS HA) SODIUM AD- SORP- TION (MG/L RATIO 44 0 10 4.7 14 32 1 6.8 3.7 13 ALKA- POTA8- LINITY 8IUM, HAT HH DI8- TOT FBT SULFIDB SOLVED FIELD TOTAL (MQ/L MG/L AS (MQ/L AS K) 28 2 6.6 2.8 9.8 0.8 1.4 0.9 3.6 1 1.2 CACO3 28 56 20 38 36 30 CHLO- SULFATB RIDE, DI8- DIS- SOLVED SOLVED (MG/L <0.5 3.8 <0.5 3.6 3.2 (MQ/L AS 8) AS 8O4) AS CL) 12 16 14 DATE OCT 1990 02... DEC 03... FEB 1991 05... APR 04... JUN 04... AUG 06... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 __ -- <0.10 -- 0.20 SOLIDS, RESIDUE DIS- SOLVED (MG/L AS 8IO2) 22 25 24 KJM OF !ON8TI- rUBNTS, DIS- SOLVED (MG/L) 75 — — 100 — 84 SOLIDS, DIS- SOLVED (TONS PER DAY) 14.1 — — 3.53 — 1.60 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 8 96 21 14 61 4 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.099 0.170 0.28 0.120 0.063 — NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.030 0.021 0.020 0.010 <0.010 NITRO- GEN, N02+N03 TOTAL (MQ/L AS N) 0.100 0.200 0.300 0.140 0.073 0.058 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.010 0.120 0.021 0.050 0.040 <0.010 NITRO- GEN, ORGANIC TOTAL (MQ/L AS N) 0.19 0.68 0.38 — 0.56 — non-ideal count RIO FAJARDO BASIN 50071000 RIO FAJARDO NEAR FAJARDO, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 305 DATE OCT 1990 02... DEC 03... FBB 1991 05... APR 04... JUN 04... AUG 06... DATE OCT 1990 02... DEC 03... FBB 1991 05... APR 04... JUN 04... AUG 06... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 0.80 0.40 <0.20 0.60 0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 0.30 1.0 — — 0.67 0.26 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 1.3 4.4 — -- 3.0 1.1 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.030 0.130 0.041 0.040 <0.010 0.010 MERCURY TOTAL RECOV- ERABLE (UG/L AS HO) ARSENIC TOTAL (UG/L AS AS) <1 -- — <1 — — SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — -- <100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 20 — — <10 — -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 — — 1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 30 — — <10 — — MBTBY- LBNB BLUE ACTIVE SUB- STANCE (MG/L) 530 360 40 20 <0.10 <0.10 <1 <1 <1 <1 10 <0.010 20 <0.010 <1 0.04 0.03 PESTICIDE ANALYSES DATE JUN 1991 04... DATE JUN 1991 04... TIME 0950 TOTAL (UG/L) <0.010 PCB, TOTAL (UG/L) <0.1 ETHION, TOTAL (UG/L) ALDRIN, TOTAL (UG/L) <0.010 HBPTA- CHLOR, TOTAL (UG/L) CHLOR- DANB, TOTAL (UG/L) <0.1 HBPTA- CHLOR EPOXIDB TOTAL (UG/L) DDD, TOTAL (UG/L) <0.010 LINDANE TOTAL (UG/L) DDE, TOTAL (UG/L) <0.010 MALA- THION, TOTAL (UG/L) DOT, TOTAL (UG/L) <0.010 MBTH- OXY- CHLOR, TOTAL (UG/L) DI- AZINON, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) DI- ELDRIN TOTAL (UG/L) <0.010 METHYL TRI- THION, TOTAL (UG/L) BNDO- SULFAN, TOTAL (UG/L) <0.010 MIRBX, TOTAL (UG/L) <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 <0.01 <0.01 DATE JUN 1991 04... PARA- THION, TOTAL (UG/L) <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) <0.10 PBR- THANB TOTAL (UG/L) <0.1 TOX- APHBNB, TOTAL (UG/L) <1 TOTAL TRI- THION (UG/L) <0.01 2,4-D, 2,4,5-T 2, 4-DP 8ILVEX, TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) <0.01 <0.01 <0.01 <0.01 RIO FAJARDO BASIN 50072500 RIO PAJARDO BELOW FAJARDO, PR WATER-QUALITY RECORDS LOCATION.—Lat 18*19'35-, long fiS»38'47-, 1.2 mi (1.9 1m) •outlnmftt of Playa d* Fajardo, and •ast of Fajardo plaza. DRAINAGE AREA.--23.4 •!* (C0.fi ItM2 ) . PERIOD OF RBCORO.--Water yaara 1974 to currant yaar. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO 8BPTBMBER 1991 0.5 (0.8 k») DATE MOV 1990 07... DEC 03... FBB 1991 05... APR 04... JON 04... ADO 06... TIME 0855 1145 1040 1045 1245 1330 DIS- CHARGE, INST. CUBIC FEET PER SECOND fil E500 54 10 9.4 8.5 SPE- CIFIC CON- DUCT- ANCE (US/CM) 158 117 114 219 184 174 PH (STAND- ARD UNITS) 7.4 6.9 7.1 7.0 8.0 8.0 TEMPER- ATURE WATER (DBG C) 25.5 24.5 23.0 27.5 29.0 31.5 TUR- BID- ITY (NTU) 8.0 93 9.1 1.5 1.4 2.5 OXYGEN, DIS- SOLVED (MG/L) 6.8 8.0 8.4 8.4 9.6 8.6 OXYQKN, DIS- SOLVED (PER- CENT SATUR- ATION) 82 94 97 105 124 111 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 26 17 <10 <10 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K800 390 5900 420 K1000 100 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 510 600 3800 K10 K120 120 DATE NOV 1990 07... DEC 03... FEB 1991 05... APR 04... JUN 04... AUG 06... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH NAT DI8- (MG/L TOT FLD SOLVED AS CACO3) CACO3 MQ/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MQ/L (MG/L AS CA) AS MB) AS NA) 44 0 11 4.1 13 57 0 14 5.4 19 47 0 11 4.7 19 SODIUM AD- SORP- TION RATIO ALKA- POTA8- LINITY 8IUM, NAT NH DIS- TOT PET 8ULFIDB SOLVED FIELD TOTAL AS K) 0.8 1.3 1.5 1.2 CACO3 34 31 26 50 30 39 <0.5 <0.5 CHLO- 8ULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS 8) AS 804) AS CL) 6.1 21 5.5 34 4.4 25 SOLIDS, DATE NOV 1990 07... DEC 03... FBB 1991 05... APR 04... JUN 04... AUG 06... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 — — 0.10 -- 0.20 SILICA, DIS- SOLVED (MO/L AS SI02) 23 — — 23 — 23 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 100 ._ — 132 -- 112 RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL PER PENDBD (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) <1 91 13 3 3 8 0.370 0.180 0.190 — 0.130 0.063 0.030 0.020 0.010 •cO.010 0.020 0.020 0.400 0.200 0.200 0.095 0.150 0.083 0.040 0.080 0.060 0.040 0.020 0.030 0.16 0.22 0.44 — 1.2 0.27 K * non-idMl count B « RIO PAJARDO BASIN 50072500 RIO PAJARDO BELOW PAJARDO, PR--Continued MATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 307 DATE NOV 1990 07... DEC 03... PBB 1991 05... APR 04... JON 04... AUG 06... DATE NOV 1990 07... DEC 03... PBB 1991 05... APR 04... JON 04... AUG 06... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 0.30 0.50 <0.20 1.2 0.30 IRON, TOTAL RECOV- ERABLE (UG/L AS KB) NITRO- GEN, TOTAL (MG/L AS N) 0.60 0.50 0.70 — 1.4 0.38 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 2.7 2.2 3.1 — 6.0 1.7 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.030 0.140 0.030 0.030 0.040 0.040 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 — — <1 — — SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 ~ — <100 — ~ SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 20 — — 20 — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 — — <1 — — PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <10 — — <10 — ~ MBTHY- LBNE BLUE ACTIVE SUB- STANCE (MG/L) 840 360 120 60 <0.10 <0.10 10 <0.010 <0.010 0.03 0.02 H H 1 TOTAL 54 L TOTAL 4: Id O H » Id H H H H * «e CD i^ •J Id M H II Id Ul an M SS n n 1 1 H OP 0 VI «J \Q M 0 0 nn Hd Hd u uii H <* H »OP M • • H H MWI •J«e OP VI OP VI H on <«H H M ** * «J Id «J H Id CD • » • VI* • t« ui oon UI^JCD Id WOP H M • • on on H «» •J «JUI . M • • Id H Id «J Id O fc H VI U1H H HO * ui oan an <« o> H • «J- • IdOO « M » H H Id OOP H •» • • on on H ui <0* UIOP «H Id H * MH H Id • Mopen ui » OP • en • on • • M ui H * en vi M Id WOP H H • . on an o ui H CD en o vi M ui Id WOP HO • • on vi o * o-»J vi an o M VI VI • M £ w H i^ f4 ^** ^S -JCD vi- «kid • Ul * MH fc Ul 0 M on on -J ui w oon • vi on • OP ui w on » id ui Id <«OP H M • • OK Id 0 Ul 2 U1fc • VI • • VIH<0 H OP W IdldMMMM MMMMM M H H H H HHHHH H 5 H O <0 CD ~1 On VI * Id M H O <* CO -J On Vl^ldMH O <« CD ~1 On VI * Id M H K H Id M fc M fc MM H^ H H VI H VI Id M M H Id HHH id t« H ui* an MOP4 MM HH MM H H H H HH iidM-^ido «J an -«J M M en *J *J t« ui CD -J OB CD <« OP w w OP w M M w o H 9S i vi en ~J «* «BH<«H OIAOUIH WHOP co i en o> t« ui co OP id » o * OP H M •«* id OP wo o -J OP vi 50 H MHHH HH^M HMH H Id k on 0 H OW OP VI -J 0 VI fc VI-JCDUI^J K fc H H H M H i w w ui H Vi vi on o w o «J on on on on on OP on w * en OP -J -J w w on on on on Cj i w on -J ui o MMHOM co an -i w opopwfeo VIM*«JW Z H H H * enonuiuioBen H vi * M ui en ^J com OPOWM M M ui on on OM id P M VI H H H in* COM M id -^ OP vi on OP OP w M OP w s. H 9 * 8 S ^ M § 5 H *" £ S * S % M 8 i S* H a *° sg i i " < •< H 11 J ^ " i Hw w0 igSi H ve W H M H Id0 -J OP H M WI Ul OP H O 1tr an H * VI •J OP Ul M M M Ul en-j H ? f H> 1, i2 8 ? ~a i So rr If -s ~? ~£ rr P • r H> *s. ~? o fir ga 53 11^ H> _ ~S S _r ? ** § 3 50 1 l•e if ftP 8ri o 3 ?»i rr5* p0g1 8 H- P* I OHi on VIo HI rj, •x. n H OP ^ *L >» n i gr ^*" 3 IR PBRIOD C , from rat charge, 1. VIH-Hd !i! o i °MK * rr •) M E B 41 >.f e • ft • ^ 5 & wa M 0«j >%? i * * ? en H?° ?OP(t H • i* * ""H §o n n H- — H • 0 > tj m • 9 H 1 » f H Is p % ft• 0 | S • Q H-D- H rr p w H * i HI V rr pi ICHARGB.— 1 re-ft/yr ( r). H W Id 3 ^S H r* « • ' I v J.M 8,2 i< **» t ~ §H •< » S HIt, H- H 1?i" • w iiS-" * •N?U1 .-. Ul OH * H- 00 ^•H * ^% % * o o S H 55 8- I Hift n i 0 HI S. .r except 1 HI rr | |T & & H- HJ ^ ft H- 8 1 5| % 13. • 3 n' Hi Q if ffl SIT >r- stage n •graphic •• D S rri f Q 3 | &i M ^0 ^ 3 ti • M 1 H- 0p 8. Q | H- H M 0 M O Hirr on H on II. % DRAXNAQB AF PBRIOD OF F water yea Sr! £ H§ wo i Wl> H Ul 1 > 1 1 M on Ci on •* ** m "< P- fi M IS s • WI H M ? an ?f ? Hi* — r & • • S » Ul » Ul S o" § * * | S | • • 53 & i H D 2S* S w» % VI Vw 9 en» ia » ? 8 ?& i ? 8 1 to rr o-? s i C 6 1 9 is B Hii 1 0 . HH- — g gH 1 ? LOCATION. -- at Bl Yun 5.3 ai (fl w.er a- ?rt i H & H OP P «H it* P^S !?*" rr «H 81 f! n p «4 Ii? c * *• » ft -j &n * 0 f o 8 ** J2*,- • HI N *1 H rs! nS KI f!f S3 9 Q P •Sn: ?o »s KO 0 o H B1 ** 4 D * J? Ml • H- OP&nP ?* U»fT H- E§ H O HO or! ••0 HHi 0 Hi P-M I & H 1 ( ( '^~-^^~^ .«*»*.»») / ^^> *i'» SEA EXPLANATION SURFACE-WATER STATION AND NUMBER 0835 QUALITY-OF-WATER STATION AND NUMBER 96 WELL AND WELL NUMBER Figure 21.--Southeastern river basins the Rio Humacao to Rio Seco basins. CO 312 RIO HUMACAO BASIN 50081000 RIO HDMACAO AT LAS PIBDRAS, PR LOCATION.--Lat 18°10'27», long 65«52'11-, Hydrologic unit 21010005, on left bank at downstream aid* of bridge on Highway 921, 0.6 ml (1.0 km) aoutheaat of junction with Highway 30, 0.8 mi (1.3 km) downstream from Quebrada Blanca and 0.8 mi (1.3 km) aouth of Laa Piedraa. DRAINAQB AREA.--6.65 mi* (17.22 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—September 1958 to December 1967 (monthly diacharge October 1987 to current year. »nta), JUly 1974 to September 1977, OAQB.—Water-atage recorder. Elevation of gage la 260 ft (79 m), from topographic map. Prior to July 1974, creat-atage gage at different datum. July 1974 to September 1977 at aite 90 ft (27 m) upatream at preaent datum. REMARKS.—Record* fair except thoae above 1,000 ft'/a (28.3 mVa), which are poor. Gage-height and precipitation aatellite telemetry at atation. AVERAGE DISCHARGE.--? yeara (1975-77, 1988-91), 22.7 ftVa (0.643 mVa), 46.36 in/yr (1,178 mm/yr), 16,450 acre-ft/yr (20.3 hmVyr). EXTREMES FOR PERIOD OF RECORD.--Maximum diacharge, 20,800 ft'/a (589 mVa) Sept. 6, 1960, gage height, 34.4 ft (10.485 m), datum then in uae, from floodmarka, and rating curve extended above 5,300 ft'/a (150 mVa) on bails of alope-area measurement of peak flow; minlmun daily diacharge, 2.2 ftVs (0.062 mVa) July 16, 1974. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base diacharge of 1,000 ftVs (28.3 mVa) and maximum (*)i Diacharge (ftVa) (mVa) Gage height (ft) (m) Date Time June 30 1300 1,370 38.8 5.26 1.599 Minimum daily diacharge, 4.9 ft1/a (0.139 m'/a), June 17. Date July 1 Time 0530 Diacharge (ftVa) (mVa) •2,460 69.7 Gage height (ft) (m) •6.99 2.130 DISCHARGE, CUBIC FBBT PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 12 2 9.6 3 8.2 4 8.4 5 8.0 6 8.4 7 8.3 8 8.1 9 8.2 10 80 11 26 12 12 13 18 14 12 15 11 16 17 17 1« 18 17 19 58 20 53 21 204 22 28 23 27 24 49 25 106 26 66 27 34 28 43 29 57 30 41 31 24 TOTAL 1077.2 MEAN 34.7 MAX 204 KIN 8.0 AC-FT 2140 CFSM 5.23 IN. 6.03 28 22 18 18 32 23 16 16 15 14 14 13 13 13 13 13 12 12 19 14 29 16 13 13 12 13 15 14 15 36 —— 514 17.1 36 12 1020 2.58 2.88 CAL YR 1990 TOTAL 4952.5 WTR YR 1991 TOTAL 5839.8 21 23 27 21 16 15 14 14 14 14 14 14 13 22 18 16 14 13 13 13 13 13 12 12 12 12 13 13 15 17 132 593 19.1 132 12 1180 2.88 3.32 MEAN MEAN 22 15 17 14 15 13 17 15 14 14 13 14 13 13 13 12 12 11 11 10 10 10 10 10 10 10 9.7 9.7 9.4 9.0 11 388.8 12.5 22 9.0 771 1.89 2.17 13.6 MAX 16.0 MAX 10 9.4 11 9.7 9.1 27 17 10 9.7 9.6 19 71 25 12 15 12 10 10 24 12 14 11 10 16 11 10 9.7 23 ~- 437.2 15.6 71 9.1 867 2.35 2.45 204 MTN 369 MTN 13 10 10 10 9.4 27 14 12 11 9.6 9.4 9.9 8.4 9.0 8.6 8.0 7.9 7.5 9.7 8.1 7.7 11 9.1 8.0 7.4 7.4 7.4 7.3 6.8 6.8 6.8 297.3 9.59 27 6.8 590 1.44 1.66 5.2 AC-FT 4.9 AC-FT 6.8 7.2 7.3 6.8 6.6 6.6 6.6 6.6 7.0 21 9.3 8.0 7.4 7.1 8.2 7.6 6.9 7.3 7.0 6.6 6.6 6.6 6.5 6.3 6.7 6.8 6.0 6.0 6.0 5.9 —— 221.3 7.38 21 5.9 439 1.11 1.24 9820 11580 5.5 5.5 6.4 6.0 8.1 10 7.5 7.5 8.9 9.8 7.4 6.8 6.8 7.2 7.6 7.4 7.6 19 9.8 10 8.6 23 10 8.2 17 9.5 7.5 6.8 6.6 6.6 6.3 274.9 8.87 23 5.5 545 1.33 1.54 CFSM 2.04 CFSM 2.41 12 9.7 7.4 6.6 8.4 11 8.7 7.6 7.0 6.6 S.I 9.0 8.1 6.8 6.5 5.7 4.9 7.2 6.4 6.2 17 9.5 7.6 7.6 6.9 6.1 7.0 7.0 7.0 286 —— 515.6 17.2 286 4.9 1020 2.58 2.88 IN. 27 IN. 32 369 30 18 15 12 10 9.3 8.7 8.7 8.2 7.7 7.7 7.7 7.5 13 S3 14 10 9.6 13 8.9 8.3 8.7 10 9.0 8.0 8.4 8.3 7.8 13 16 738.5 23.8 369 7.5 1460 3.58 4.13 .70 .67 9.7 8.9 9.0 7.4 8.1 8.7 7.8 7.2 6.8 6.6 6.6 6.6 6.5 6.0 6.0 6.1 9.7 7.8 7.3 10 8.0 15 10 7.3 6.5 6.0 118 40 13 13 9.4 399.0 12.9 118 6.0 791 1.94 2.23 8.5 7.7 7.6 7.1 7.1 6.8 7.1 6.8 7.3 8.4 7.9 7.0 6.6 6.5 6.0 6.3 25 11 8.0 7.7 9.8 24 16 12 10 8.8 12 16 86 22 —— 383.0 12.8 86 6.0 760 1.92 2.14 RIO HDHACAO BASIN 50081000 RIO HDHACAO AT LAS PIBDRAS, PR--Continued WATER QUALITY RECORDS 313 PERIOD OF RECORD.-- OCTOBER 1989 TO CURRENT YEAR DATE STRBAMFLOW, SPECIFIC CON- TBMPBRA- TIHB INSTANTANBODS DDCTANCB TURB (CFS) (UMHOS) (DBQ C) DATS TIME FEB. 02 1205 MAR. 22 1054 MAY 17 1055 JDN. 20 1000 19.4 11.1 7.19 6.02 159 185 190 190 22.0 22.5 25.0 24.5 JUL. 19 1259 ADG. 21 1139 SEP. 11 1341 STRBAMFLOW, INSTANTANBODS (CFS) 9.35 8.15 8.25 SPECIFIC CON- DUCTANCE (UMHOS) 190 180 185 TEMPERA- TURE (DBG C) 25.5 25.5 27.5 314 RIO HUMACAO BASIN 50082000 RIO HDMACAO AT HIGHWAY 3 AT HDMACAO, PR WATBR-QOALITY RECORDS LOCATION.—Lat 18°08'49", long 65°49'37", at bridge on Highway 3, 300 ft (91 m) downstream from Quebrada Mariana, and 0.4 Mi (0.6 km) south of Humacao. DRAmAOB AREA.—17.3 mi1 (44.8 km2). PERIOD OP RECORD.—Water years 1958-66, 1969 to current year. WATBR-QOALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 24... DEC 20... FEB 1991 08... APR 22... JDN 18... ADO 19... TIME 1120 0845 0940 1130 1345 1140 DIS- CHARGE, INST. CUBIC FEET PER SECOND 49 20 18 10 10 10 SPE- CIFIC CON- DUCT- ANCE (US /CM) 235 318 324 396 365 350 PH (STAND- ARD UNITS) 7.4 7.7 7.1 7.1 7.5 7.5 TEMPER- ATURE HATER (DBG C) 28.0 22.0 23.5 29.0 30.5 30.1 TUR- BID- ITY (NTU) 100 83 27 2.8 2.8 5.5 OXYGEN, DIS- SOLVED (MG/L) 7.7 6.9 7.3 6.3 4.5 4.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 98 78 85 82 59 52 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 26 17 29 52 24 25 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K100000 64000 310000 K960000 680000 530000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 36000 10300 K130000 220000 120000 69000 DATB OCT 1990 24... DEC 20... FEB 1991 08... APR 22... JUN 18... AUQ 19... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS CACO3) CACO3 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS HA) 70 1 19 5.4 18 87 0 25 5.9 28 100 3 29 7.0 31 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT FET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.9 3.4 1 3.1 1 2.4 CACO3 69 93 98 93 100 110 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L <0.5 14 <0.5 14 14 (MG/L AS 8) AS SO4) AS CL) 23 32 37 SOLIDS, RESIDUE DATB OCT 1990 24... DEC 20... FBB 1991 08... APR 22... JUN 18... AUG 19... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- <0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 28 -- -- 36 — 39 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 152 -- -- 200 -- 220 SOLIDS, DIS- SOLVED (TONS PER DAY) 20.2 — — 5.42 — 5.94 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 121 109 53 6 7 22 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.520 0.830 0.760 0.530 0.230 0.330 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.080 0.070 0.040 0.040 0.020 0.040 NITRO- GEN, , NO2+NO3 TOTAL (MG/L AS N) 0.600 0.900 0.800 0.570 0.250 0.370 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.240 0.750 1.30 2.80 1.40 0.720 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.76 0.35 0.40 0.80 0.90 0.18 non-ideal count RIO HUMACAO BASIN 50082000 RIO HUMACAO AT HIGHWAY 3 AT HUMACAO, PR—Continued WATER-QUALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 315 DATE OCT 1990 24... DEC 20... FEB 1991 08... APR 22... JDN 18... ADO 19... DATE OCT 1990 24... DEC 20... FEB 1991 08... APR 22... JDN 18... ADO 19... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.0 1.1 1.7 3.6 2.3 0.90 IRON, TOTAL RECOV- ERABLE (OG/L AS FE) £400 -- -- 570 -- — NITRO- GEN, TOTAL (MG/L AS N) 1.6 2.0 2.5 4.2 2.6 1.3 LEAD, TOTAL RECOV- ERABLE (DG/L AS PB) 5 — — 5 — — NITRO- GEN, TOTAL (MG/L AS N03) 7.1 8.9 11 18 11 5.6 MANGA- NESE, TOTAL RECOV- ERABLE (DG/L AS MN) 430 -- — 160 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.190 0.330 0.380 0.750 0.440 0.400 MERCURY TOTAL RECOV- ERABLE (DG/L AS HG) <0.10 — — 0.20 — — BARIUM, TOTAL ARSENIC RECOV- TOTAL BRABLB (DG/L (DG/L AS AS) AS BA) <1 200 — — <1 <100 — — — — — SILVER, 8BLE- TOTAL NIDM, RECOV- TOTAL BRABLB (DG/L (DG/L AS SB) AS AG) <1 3 — — <1 9 — — BORON, TOTAL RECOV- ERABLE (OQ/L AS B) 30 — -- 70 — — — ZINC, TOTAL RECOV- ERABLE (DG/L AS ZN) 40 — — 20 -- — CHRO- CADMIDM MIDM, TOTAL TOTAL RECOV- RECOV- ERABLE BRABLB (DG/L (OO/L AS CD) AS CR) <1 2 — — <1 3 — — — ~"~ CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (DG/L) <0.010 6 — — <0.010 13 — — COPPER, TOTAL RECOV- ERABLE (DG/L AS CD) 20 — — 20 — "~— MBTHY- LBNB BLUE ACTIVE SUB- STANCE (MG/L) 0.06 — — 0.30 — — RIO GUAYANBS BASIN 50083500 RIO QOAYANB8 AT YABOCOA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°03'33", long 6S«S4'03", at bridge on Highway 182, 1.4 ml (2.2 km) west-northwest of plaia. DRAINAGE AREA.--17.2 mia (44.6 km2 ). PERIOD OF RECORD.—Water years 1958-62, 1968-70, 1980 to currant year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 Yabucoa DATE OCT 1990 29... DEC 19... FBB 1991 08... APR 23... JUN 17... AUG 13... DATE OCT 1990 29... DEC 19... FBB 1991 08... APR 23... JUN 17... ADO 13... TIME 1220 1225 0815 1130 1215 1150 HARD- NESS TOTAL (MG/L AS 37 — — DIS- CHARGE, INST. CUBIC FEET PER SECOND 129 32 39 21 14 14 HARD- NESS NONCARB WH WAT TOT FLD MQ/L AS 0 -- -- 51 0 — 53 -- 0 SPE- CIFIC CON- DUCT- ANCE (US/CM) 135 175 161 160 150 175 PH TEMPBR- (STAND- ATURB ARD UNITS) 7.1 7.1 7.0 7.0 7.5 7.4 WATBR (DBG C) 25.0 23.5 21.5 28.0 27.0 27.5 MAGNB- CALCIUM DIS- SOLVED (MG/L 9.4 — — 13 — 13 SIUM, DIS- SODIUM, DI8- SOLVED SOLVED (MG/L 3.3 __ -- 4.5 -- 4.9 SOLIDS, FLUO- SILICA, SUM (MG/L 11 — — 16 — 16 TUR- BID- ITY (NTU) 59 62 26 10 15 25 SODIUM AD- SORP- TION RATIO 0.8 __ __ 1 — 1 OXYGEN, DIS- SOLVED (MG/L) 6.3 7.7 7.7 7.1 3.4 6.7 POTAS- SIUM, DIS- SOLVED (MG/L 1.9 — — 1.4 — 1.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 76 89 87 89 42 83 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS 42 66 56 61 67 62 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 25 16 20 18 <10 14 SULFIDB TOTAL (MG/L OTO'0> OT> OTO'0> 0» T> T> T> T> OT'0> OT'O 08C 08C CT OOCC 00t6 (a/OM) SDNYiS -SOS SAIJOY SflflB BNSa -AOL3II — — OT — — oc (no SY i /on) HTOYHS -AOOSH TYiLOX 'HHddOO (a/on) TYIOi SIONBBd — — T> — — C (HO SY a/on) BTHYHS -A03SH TYlOi 'HQIH -OHHO (MO SY a/OM) TYiOX SQINYAO — ~ T> — -- T> (ao SY a /on) sasYHH -AOOSH OYJXU lUUHOYO (HZ SY a/on) BOBYHH -AOOSH TYlOi 'OHIZ — — OT> — — OC (B SY a/ on) BTHYHS -AOOBH TYIOi 'MOHOB (OY SY a /on) BaBYHB -AOOSH TYiOi 'HBAaiS __ ~ ooc ~ — OOT> (YB SY a/on) SIHYHa -AOOBB TYiOX 'HQIBYB (BS SY a/on) TYJOi 'iiaiM -BOBS — — T> — — T> (SY SY a/on) OYJOX OIMSSHY (OB SY a /on) BaBYHB -AOOBB TYiOX AHnOHHH 080*0 OAO'O OOT'O 090*0 OLO'O OTC'O (d SY a/OM) TY.LOX SHHOBd -SOBd (MM SY a/on) BOBYHB -AOOBB OY.LOX 'BSBN -YOMYM 9'C O'C — — — f8 (COM SY a/QR) OY1OX 'MBO -OBXIM (Bd SY a /on) BTHYHB -AOOBB OY10X 'OYBa 85*0 9fO — — — 6'T (M SY a/DM) 1Y10X 'MBO -OHilN (M SY a/on) BOBYHB -AOOBB TYIOi 'MOHI OfO oc-o OS'0 OfO> OZ*0> C'T (M SY a/BR) OYIOX OIMYOUO + YIMOM -MY'MBO -OBXIM "•6T DQY •"8T nor •••co AY* ••*9Z T66T BB* •"AT oaa •••ft 0661 IOO sxva •*'6T DDY •"8T nor •••co AY* ••*9t T66T BS* •"AT oaa '"ft 066T iOO HXYQ eie T66T HSBMSXdBS OO, 066T BSBOAOO BYSA BBXYM 'YXYd AAIOYnO-BSXYM d 'SBNYJLYOD BQ YJLYTH AY BXOOM BAOBY SBHYAYOD OIH OOS9800S MISYB SSNYJLYOD OIB 320 RIO MAUNABO BASIN 50090500 RIO MAUNABO AT LIZAS, PR LOCATION.«Lat 18«01'38", long 65*56'24", Hydrologic Unit 21010005, on right bank, off Highway 759 at Lisas, about 1.0 mi (1.6 km) downstream Quebrada Coroco, and about 3.0 mi (4.8 km) northwest of Maunabo. DRAINAGE AREA.--5.38 mi* (13.93 km*). WATBR-DISCHARGE RECORDS PERIOD Or RECORD.—February 1971 to January 1985, February to September 1991. GAGE.—Hater-stage recorder. Elevation of gage is 230 ft (70 m), from topographic map. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.—13 years (1972-84), 18.4 ftVs (0.521 mVs), 46.44 in/yr (1,180 mm/yr), 13,330 acre-ft/yr (16.4 hmVyr)! median of yearly mean discharges, 15 ft'/s (0.42 mVs), 10,900 acre-ft/yr (13 hm'/yr). EXTREMES FOR PERIOD OF RECORD.—Maximum discharge, 6,780 ftVs (191 mVs), Nov. 25, 1977, gage height, 14.84 ft (4.523 m) from rating curve extended above 50 ftVs (1.42 mVs) on basis of step-backwater analysis; minimum daily discharge, 2.2 ftVs (0.062 mVs) July 16, Aug. 7, 13, 1974. EXTREMES FOR CURRENT PERIOD.--Peak discharges greater than base discharge of 600 ft'/s (17.0 mVs) and maximum (*)i Date Feb. 18 June 30 Time Discharge (ftVs) (mVs) 1930 839 1300 *2,300 23.8 65.1 Gage height (ft) (m) 7.40 2.256 *10.08 3.072 Date July 1 Sept. 29 Discharge Time (ft'/s) (mVs) 0045 1115 997 646 28.2 18.3 Gage height (ft) (m) 7.78 2.371 7.03 2.143 Minimum daily discharge, 4.1 ftVs (0.116 mVs), June 16, 17. DISCHARGE, CUBIC FEET PER SECOND, WATBR YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. OOP NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 11 9.3 8.6 84 52 48 18 14 14 13 14 12 11 15 —— ___ —— 11 10 13 11 11 19 13 11 9.7 9.0 8.7 8.3 7.9 8.7 8.2 7.6 7.3 7.4 8.0 7.3 6.9 11 8.1 6.9 6.6 .6 .7 .3 .1 .0 5.9 274.2 8.85 19 5.9 544 1.64 1.90 6.3 9.5 6.5 5.9 5.8 5.6 5.4 5.7 5.7 5.6 9.3 6.7 5.8 6.1 8.0 6.2 5.5 6.5 6.0 5.4 5.3 5.6 5.0 4.8 6.1 5.3 4.9 4.9 4.8 4.6 —— 178.8 5.96 9.5 4.6 355 1.11 1.24 4.5 4.4 4.4 9.3 5.5 6.8 8.0 7.2 7.1 5.1 5.3 4.8 4.7 4.8 5.2 5.5 7.4 5.4 5.3 5.8 6.0 5.9 5.2 4.9 e!3 •6.2 e5.4 eS.O •4.8 e4.8 e4.6 182.3 5.88 13 4.4 362 1.09 1.26 12 5.9 5.0 4.7 4.8 8.3 8.8 5.2 4.7 4.6 4.9 10 5.3 4.5 4.3 4.1 4.1 4.8 5.2 4.9 12 5.7 7.0 6.3 5.6 5.2 14 6.7 5.0 267—— 450.6 15.0 267 4.1 894 2.79 3.12 283 22 16 18 e9.5 e8.5 e7.5 e7.0 •6.6 •6.4 •6.4 •6.2 •6.2 •6.2 •6.4 •50 • 12 9.0 8.9 8.8 7.0 6.2 7.5 7.1 6.2 6.7 8.4 8.5 14 12 12 600.2 19.4 283 6.2 1190 3.60 4.15 14 9.2 8.5 8.2 6.7 9.2 7.2 7.0 6.6 6.8 7.4 7.4 8.2 7.1 7.3 7.7 16 11 8.6 8.5 8.9 14 8.9 7.5 6.7 6.7 33 18 12 11 14 313.3 10.1 33 6.6 621 1.88 2.17 9.5 8.8 7.5 7.0 6.6 6.9 6.8 6.1 12 8.4 7.6 6.2 5.6 5.1 4.7 5.0 22 7.0 5.3 5.7 11 21 31 8.5 7.7 6.3 9.6 7.8 115 11—— 382.7 12.8 115 4.7 759 2.37 2.65 Estimated RIO MAUNABO BASIN 50091000 RIO MAUNABO AT MAUNABO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18«00'24", long 65«54'19", at bridge on Highway 3, 0.4 mi (0.6 ka) southwest and 1.3 B! (2.1 taa) upstream from mouth. DRAINAGE AREA.--12.4 •!* (32.1 km2 ). PERIOD OP RECORD.—Hater years 1958-66, 1975 to current year. WATER-QUALITY DATA, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 321 of Mannatm plaxa, DATE OCT 1990 29... DEC 19... PBB 1991 26... APR 23... JUN 17... AOQ 13... TIME 1010 1025 0935 0850 1010 0935 DIS- CHARGE, INST. CUBIC PBBT PER SECOND 93 1C 21 9.8 6.5 2.7 SPE- CIFIC CON- DUCT- ANCE (US/CM) 199 272 2 1C 252 280 310 PH (STAND- ARD UNITS) 7.2 7.C 7.5 7.3 7.5 7.C TEMPER- ATURE WATER (DBQ C) 2C.O 24.0 2C.O 26.0 28.0 28.0 TUR- BID- ITY (NTU) 4.0 13 7.0 4.9 5.3 9.0 OXYGEN, DIS- SOLVED (MG/M 7.1 7.5 7.C 6.6 7.1 6.7 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 87 88 93 80 89 83 OXYGEN DEMAND, CHEM- ICAL (HIGB LEVEL) (MG/L) 26 12 17 <10 <10 24 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K10000 710 2100 2400 260 K150 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3500 100 250 450 K20 K140 DATE OCT 1990 29... DEC 19... FBB 1991 26... APR 23... JUN 17... AUG 13... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL NH NAT DIS- (MG/L TOT FLD SOLVED AS CACO3) CACO3 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L AS CA) AS MO) AS HA) 57 0 14 5.3 17 84 0 20 8.2 23 110 0 27 11 32 SODIUM AD- SORP- TION (MG/L RATIO ALKA- POTA8- UNITY SIUM, NAT NH DIS- TOT FBT SULFIDE SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 2.0 1.2 3.0 CAC03 54 93 84 87 93 100 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS 8) AS 804) AS CL) <0.5 9.9 22 <0.5 10 24 18 38 DATE OCT 1990 29... DEC 19... FEB 1991 26... APR 23... JUN 17... AUG 13... K * non-ideal FLUO- RIDB, DIS- SOLVED (MQ/L AS F) 0.10 -- — 0.10 — 0.20 count SILICA, DIS- SOLVED (MG/L AS SI 02) 31 — — 41 — 40 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 134 — -- 180 — 229 SOLIDS, DIS- SOLVED (TONS PER DAY) 33.5 — — 4.75 — 1.68 SOLIDS, RESIDUE TOTAL NITHO- NITRO- NITHO- AT 105 GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 SOS- TOTAL TOTAL TOTAL FENDED (MG/L (MG/L (MG/L (MG/L) AS N) AS N) AS N) 49 15 6 10 7 48 0.680 0.560 0.480 0.530 0.440 1.03 0.020 0.040 0.020 0.020 0.040 0.070 0.700 0.600 0.500 0.550 0.480 1.10 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.050 0.750 0.240 0.060 0.360 0.220 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.55 0.25 0.36 0.24 0.34 0.38 322 RIO MAUNABO BASIN 50091000 RIO MAUNABO AT MAUNABO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 29... DEC 19... FBB 1991 26... APR 23... JUN 17... AUG 13... DATE OCT 1990 29... DEC 19... FBB 1991 26... APR 23... JUN 17... AUG 13... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 1.0 0.60 0.30 0.70 0.60 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.3 1.6 1.1 0.85 1.2 1.7 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 5.8 7.1 4.9 3.8 5.2 7.5 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MO/L AS P) 0.060 0.170 0.150 0.210 0.530 0.890 MERCURY TOTAL RECOV- ERABLE (UG/L AS HO) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AGO BORON, TOTAL RECOV- ERABLE (UG/L AS B) 20 — -- 20 — -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — -- CYANIDE TOTAL (MO/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 1 -- -- 1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) 20 — — <10 — -- MBTHY- LENB BLUB ACTIVE SUB- STANCE (MO/L) 3700 720 130 40 <0.10 <0.10 <0.010 <0.010 0.01 0.03 RIO CKCCO BASIN 50091800 RIO CHICO AT PROVIDENCIA, PR WATER-QUALITY RECORDS LOCATION.--Lat 17«59'16", long 66«00'18", at flat low bridge 200 ft (61 m) south of Highway above wrath, and 1.5 mi (2.4 km) southeast of Patillas plaza. DRAINAGE ARBA.--4.9 ml* (12.8 km2). PERIOD OP RECORD.—Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 323 3, 0.5 mi (0.8 km) DATE OCT 1990 31... DEC 14... FBB 1991 25... APR 12... JUN 07... AUG 12... TIME , 0950 0810 0900 1035 1045 1145 DIS- CHARGE, INST. CUBIC PBBT PER SECOND 25 35 3.3 1.1 1.0 0.23 SPE- CIFIC CON- DUCT- ANCE (US/CM) 259 134 357 407 420 478 PH (STAND- ARD UNITS) 7.7 7.3 7.9 7.7 7.5 7.3 TEMPER- ATURE WATER (DBG C) 25.5 23.0 24.0 26.5 30.5 31.5 TUR- BID- ITY (NTU) 19 130 2.5 3.4 44 3.0 OXYGEN, DIS- SOLVED (MG/L) 7.1 7.3 7.8 7.6 5.2 3.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 86 84 92 94 69. 45 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 15 <10 17 31 36 40 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3200 71000 430 K930 560 2300 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 2700 82000 310 K1000 410 3200 DATE OCT 1990 31... DEC 14... FBB 1991 25... APR 12... JUN 07... AUG 12... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CACO3) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MQ/L (MG/L AS CA) AS MG) AS NA) 79 0 19 7.7 26 100 1 24 9.7 41 85 0 22 7.4 59 SODIUM AD- SORP- TION RATIO ALKA- POTAS- UNITY SIUM, WAT WH DIS- TOT PET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 1 1.7 2 5.1 3 10 CACO3 82 48 110 98 62 66 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L • • ot e» K OB «0 Ot I0M O 1/1 OB UK OM «j «• u U U U VI H • • M K *> Ot UO «J U K • *> VIO O O H«fl «J MM M Uh* • . u h* -J H u o K M *. • en «J en o H » en en • • -i OB e* «• VI OB H «J • «0 M« O Ot «0 «00t MM M *. K • • VI H VIM VI *> H H M • Ot «J Ot O Ot «fl H U K* H H H M U h*MUUh*HH«**>MU »u K g «0 U «J K «J *> «0 O U O H «• «fl Ot «fl *.*.*. Ot O M M M M M U *> OB Q KVI«0 *.«b «0 Ot VI Ot «J «J Ot «• O UUOt III H H 9 I I IUMM M M M U *• Ot *> U M U U VI M 10 «0 M M U «J M ot H H H H M I I I in » « M*>MOtO «0 en M KKMUU KKKMM K«O*>OMVI i o o *> «• ot enuvi in-J*. in in «0 u «j «• K «j «A M «A *. ' ' «VI «0 IWUVIWM UVIM M U U *. VI OB KKKU MMKK -— -«» f » R R C CC* 326 RIO GRANDB DB PATILLA8 BASIN 50092000 RIO ORANDB DB PATILLA8 NBAR PATILLAS, PR—Continued (National stream-quality accounting network station) MATER-QUALITY RECORDS PBRIOD OP RBCORD.-- Water years 1960 to current year. WATER-QUALITY DATA, WATBR YBAR OCTOBER 1990 TO SEPTEMBER 1991 DIS- OXYGBN, COLI- DATB OCT 1990 15... JAN 1991 08... APR 08... JUL 24... TIME 0945 0950 0955 1030 CHARGE, INST. CUBIC FEET PBR SECOND 59 35 15 18 SPE- CIFIC CON- DUCT- ANCE (US/CM) 128 148 175 154 PH (STAND- ARD UNITS) 7.8 7.5 8.0 8.1 TEMPER- ATURE MATER (DBG C) 24.0 22.0 23.5 27.0 TUR- BID- ITY (NTU) 6.0 12 1.4 0.40 OXYGEN, DIS- SOLVED (MG/L) 8.1 8.2 8.2 8.3 DIS- SOLVED (PER- CENT SATUR- ATION) 96 93 96 102 FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K1100 5600 460 K30 STREP- TOCOCCI FECAL, (COLS. PBR 100 ML) 2300 5300 210 590 HARD- NESS TOTAL (MG/L AS CACO3) 49 46 55 47 CALCIUM DIS- SOLVED DATB (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, NAT WH SULPATB DIS- TOT PET DIS- SOLVED FIELD SOLVED (MG/L MG/L AS (MG/L CHLO- RIDE, DIS- SOLVED (MG/L PLUO- RIDB, DIS- SOLVED (MG/L SILICA, DIS- SOLVED (MG/L AS SOLIDS, RESIDUE AT 180 DBG. C DIS- SOLVED AS K) CACO3 AS SO4) AS CL) AS P) SIO2) (MG/L) OCT 1990 15... JAN 1991 08... APR08... JUL 24... 9.3 11 13 11 6.3 4.4 5.5 4.8 31 13 15 12 2 0.8 0.9 0.8 1.7 0.80 0.50 0.60 39 46 60 49 12 8.3 10 9.2 20 13 13 12 0.20 <0.10 <0.10 0.20 20 20 23 22 93 100 109 87 DATB OCT 1990 15... JAN 1991 08... APR 08... JUL 24... SOLIDS, SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 126 99 116 101 SOLIDS, DIS- SOLVED (TONS PER DAY) 14.7 9.56 4.30 4.32 NITRO- GEN, NO2+NO3 DIS- SOLVED (MG/L AS N) 0.300 0.200 0.067 <0.050 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS N) 0.010 0.050 <0.010 0.020 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.01 0.06 __ 0.03 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.40 0.40 0.40 <0.20 PHOS- PHORUS TOTAL (MG/L AS P) 0.010 0.040 0.020 0.020 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.020 0.020 <0.010, <0.010 PHOS- PHORUS ORTHO, DIS- SOLVED (MG/L AS P) 0.010 0.010 <0.010 <0.010 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS PO4) 0.03 0.03 — — K*non-ideal count RIO GRANDS DB FATILLAS BASIN 327 50092000 RIO ORANDB DB FATILLAS NEAR FATILLAS, PR- -Continued (National stream-quality accounting network station) MATER- QUALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 15... JAN 1991 08... APR 08... JUL 24... ALUM- BBRYL- INUM, ARSENIC BARIUM, LIUM, CADMIUM DIS- DIS- DIS- DIS- DIS- SOLVED SOLVED SOLVED SOLVED SOLVED (UO/L (DG/L (UO/L (DG/L (UO/L AS AL) AS AS) AS BA) AS BE) AS CD) 120 <1 11 <0.5 2.0 130 <1 12 <0.5 <1.0 20 <1 14 <0.5 <1.0 10 <1 11 <0.5 <1.0 CHRO- MIUM, COBALT, COPPER, DIS- DIS- DIS- SOLVED SOLVED SOLVED (DG/L (UO/L (DG/L AS CR) AS CO) AS CD) <3 <3 <3 <3 IRON, DIS- SOLVED (UO/L AS FE) 180 110 22 27 LEAD, DIS- SOLVED (DG/L AS FB) 27 4 1 1 DATE OCT 1990 15... JAN 1991 08... APR 08... JUL 24... LITHIUM DIS- SOLVED (UO/L AS LI) MANGA- NESE, DIS- SOLVED (DG/L AS MN) MERCURY DIS- SOLVED (UO/L AS HO) MOLYB- DENUM, DIS- SOLVED (DG/L AS MO) NICKEL, DIS- SOLVED (UO/L AS NI) SELE- NIUM, DIS- SOLVED (OG/L AS SB) SILVER, DIS- SOLVED (UO/L AS AG) STRON- TIUM, DIS- SOLVED (UG/L AS SR) VANA- DIUM, DIS- SOLVED (DG/L AS V) ZINC, DIS- SOLVED (DG/L AS ZN) <4 <4 <4 <4 68 20 7 7 47 37 43 40 <6 <6 <6 <6 18 13 7 <3 PARTICLB-SIZB DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1990 15... JAN 1991 08... APR 08... JUL 24... TIME 0945 0950 1005 1030 STREAM- FLOW, INSTAN- TANEOUS (CFS) SEDI- MENT, SUS- PENDED (MG/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 59 35 15 18 9 22 14 21 1.4 2.1 0.57 1.02 70 77 328 THIS PAGE WAS LEFT BLANK INTENTIONALLY EXPLANATION 1080 SURFACE-WATER STATION AND NUMBER 1065 QUALITY-OF-WATER STATION AND NUMBER WELL AND WELL NUMBER CREST-STAGE GAGE STATION CAfEY •' / #) • / ^' £ € *^*^ i***"^*"^ JK' •/! // 0123456 Figure 22.--South coast river-basins the Rio Salinas to Rio Jacaguas basins. 330 50100200 RIO 8ALINAS BASIN RIO LAPA NEAR RABO I»L BUSY, PR LOCATION. —Lat 18°03'36", long 66°14'28", Hydrologic Unit 21010004, on left bank, at bridge on Highway 1, Km 9.7, 1.5 mi (2.4 km) north of Rabo del Buey, and 4.4 mi (7.1 km) northeaat of Salinaa Plaza. DRAINAOB ARBA. — 9.92 mi 1 (25.69 km*). WATBR-DISCHAROB RECORDS PERIOD OF RECORD. — 1953-63 (annual low-flow measurement* only), September 1988 to current year. GAQB. — Water- atage recorder and creat-atage gage. Elevation of gage 1m 394 ft (120 m), from topographic map. REMARKS. — Record* fair except thoae for estimated daily discharge*, which are poor. EXTREMES FOR PERIOD OF RECORD. — Ma^H™- discharge, 1,750 ft'/a (49.6 m1/*), Oct. 20, 1990, gage height, 10.23 ft (3.118 m) from rating curve extended above 100 ft1/* (2.83 m1/*) on ba*i* of *tep-backwater analyai*; minimum daily discharge, 0.02 ft3/* (0.001 m1/*), Aug. 29, 1989. EXTREMES FOR CURRENT YEAR.— Peak discharge* greater than baae discharge of 200 ft3/* (5.66 m1/*) and maximum (*) t Discharge Date Oct. 9 Oct. 16 Oct. 18 Oct. 20 Oct. 21 Time 1515 1515 1930 2315 0845 (ft3/*) 1,240 437 783 *1,750 907 (mV») 35.1 12.4 22.2 49.6 25.7 Gage (ft) 9.51 7.88 8.70 *10.23 8.96 height (m) 2.899 2.402 2.652 3.118 2.731 Date Oct. 24 Oct. 25 Feb. 5 Feb. 12 Time 2015 2215 1745 1800 Discharge (Ct*/>> (mV«) 523 912 207 255 14.8 25.8 5.86 7.22 Gage height (ft) (m) 8.11 8.96 7.06 7.28 2.472 2.731 2.152 2.219 minimum daily discharge 0.16 ft1/* (0.004 mVa), July 23. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 31 2 14 3 6.1 4 4.5 5 3.9 6 3.4 7 3.2 8 17 9 97 10 51 11 19 12 19 13 65 14 55 15 44 16 84 17 60 18 120 19 84 20 94 21 242 22 137 23 107 24 141 25 185 26 164 27 127 28 109 29 97 30 94 31 81 TOTAL 2359.1 MEAN 76.1 MAX 242 MIN 3.2 AC-FT 4680 CFSM 7.67 IN. 8.85 CAL YR 1990 WTR YR 1991 74 10 69 9.1 61 11 56 10 53 7.6 43 7.4 41 7.1 36 6.6 34 5.5 32 5.5 29 6.7 26 7.0 24 5.8 22 5.8 20 5.2 20 .8 18 .8 17 .8 15 .6 24 .4 19 .3 17 .2 16 .1 15 .1 14 .2 13 .1 12 .0 11 .0 10 .5 12 .5 —— 13 853 188.7 28.4 6.09 74 13 10 4.0 1690 374 2.87 .61 3.20 .71 TOTAL 3977.83 MEAN TOTAL 4081.20 MEAN 7.8 6.1 5.1 .7 .4 .5 .5 .7 .8 .4 4.1 3.9 3.8 3.6 3.4 3.4 3.2 3.0 3.0 3.0 2.9 2.9 2.8 2.8 2.8 2.8 2.7 2.8 2.8 2.7 2.5 115.9 3.74 7.8 2.5 230 .38 .43 10.9 MAX 11.2 MAX 2.3 2.2 1.3 .65 e2.0 el. 9 e.40 .42 2.3 2.1 1.4 .60 e2.1 el. 5 e.33 .44 2.1 2.1 1.4 .54 el. 9 el.O e.31 .43 2.1 2.1 1.3 .52 el. 5 e.72 e.28 .42 20 2.3 1.2 .50 el.l e.68 e.30 .32 12 2.2 1.1 .50 el. 2 e.30 e.31 .36 7.5 2.1 1.1 - .54 el.O e.20 e.37 .60 3.5 2.0 1.3 .56 e.54 e.24 e.36 .57 2.9 1.8 1.4 .66 e.84 e.23 e.42 .46 23 1.8 1.1 .78 e.90 e.33 e.45 .48 56 1.7 1.1 e.80 e.60 e.33 e.52 .42 74 1.7 1.1 el.O el.l e.27 .50 .39 63 1.6 1.1 el. 3 el. 3 e.22 e.45 .42 20 1.6 1.1 el. 5 .74 e.21 e.74 .38 9.2 1.5 1.0 el. 3 .56 e.25 e.78 .36 6.3 1.5 .99 el. 4 .40 e4.0 e.80 .37 5.1 1.5 .93 el. 5 .36 el. 5 e.52 4.7 4.5 1.4 .90 el. 7 .34 e.70 e.40 1.2 4.3 1.4 .84 e2.0 .37 e.60 e.36 1.3 4.1 1.4 .77 e2.2 .41 e.45 e.35 .70 3.7 1.3 .80 e2.0 .43 e.25 e.40 .57 3.4 1.6 .81 e2.2 .45 e.17 el. 7 .93 3.2 1.8 .76 e2.2 .54 e.16 e2.3 1.9 3.0 1.4 .70 e2.1 .52 .19 el.O .88 2.7 1.3 .70 e3.0 .52 .18 e.80 .73 2.4 2.8 .71 e3.1 .35 .18 e.60 .85 2.2 2.1 .68 e2.5 .30 .18 .69 .80 2.4 1.6 .70 e2.3 .32 .25 .75 .68 1.6 .64 e2.3 .32 .30 .56 1.4 1.5 .64 e2.2 e2.0 e.52 .46 1.2 —— 1.4 —— e2.0 —— e.52 .45 —— 347.2 54.4 29.57 46.45 25.01 18.53 18.66 24.68 12.4 1.75 .99 1.50 .83 .60 .60 .82 74 2.8 1.4 3.1 2.1 4.0 2.3 4.7 2.1 1.3 .64 .50 .30 .16 .28 .32 689 108 59 92 50 37 37 49 1.25 .18 .10 .15 .08 .06 .06 .08 1.30 .20 .11 .17 .09 .07 .07 .09 242 MIN .06 AC-FT 7890 CFSM 1.10 IN. 14.92 242 MIN .16 AC-FT 8100 CFSM 1.13 IN. 15.30 Estimated RIO SALINAS BASIN 50100450 RIO MAJADA AT LA PLENA, PR 331 LOCATION.—Lat 18»02'40-, long 66»12'27-, Hydrologic Unit 21010004, on right bank, upstream side of bridge on Hwy 712, about 0.3 mi (0.5 km) southwest of La Plena. DRAINAGE AREA.--16.7 mi* (43.3 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—September 1988 to current year. GAGE.—Water-stage recorder. Elevation of gage is 410 ft (125 m), from topographic map. REMARKS.-Records fair. Some regulation at low flow upstream from station by local residents for agricultural purposes. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 3,820 ftVs (108 •?/•), Oct. 25, 1990, gage height, 10.34 ft (3.152 m) from rating curve extended above 100 ftVs (2.832 •?/•) on basis of step-backwater analysis and logarithmic extension; minimum daily discharge, 0.05 ft'/« (0.001 mVs), June 4-10, 1990. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 250 ft*/s (7.08 •?/•) and maximum (*) i Discharge Date Oct. 9 Oct. 18 Oct. 20 Time 1545 1945 2330 Gage height (ft) (m) 756 2,000 3,210 21.4 56.6 90.9 6.86 8.72 9.87 2.091 2.658 3.008 Date Oct. 24 Oct. 25 Time Discharge (ftV«) (mVs) Gage height (ft) (m) 1900 912 2145 *3,820 25.8 108 7.17 •10.34 2.185 3.152 MiniBum daily discharge 0.56 ftVs (0.016 ms/«). Aug. 20, Sept. 6. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN 1991 JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 8.2 5.2 3.6 2.5 1.8 2.0 2.1 9.1 120 26 9.9 9.9 56 15 13 18 18 139 77 155 320 82 52 130 343 221 155 113 82 103 77 2369.3 76.4 343 1.8 4700 4.58 5.28 1990 1991 59 50 44 43 42 36 33 31 29 26 25 24 22 21 20 19 18 17 17 20 19 18 17 16 16 15 15 15 13 15 755 25.2 59 13 1500 1.51 1.68 TOTAL 3818 TOTAL 4382 14 12 13 12 9.4 .5 .9 .5 .2 .2 10 11 9.9 14 10 9.5 8.4 7.8 7.8 7.9 8.0 7.9 8.3 8.5 8.4 8.0 7.8 7.9 9.0 9.1 13 299.9 9.67 14 7.8 595 .58 .67 .58 MEAN .71 MEAN 11 8.8 7.7 7.3 7.0 6.8 6.5 6.8 6.3 5.7 5.7 5.2 5.0 4.8 5.3 5.0 4.5 4.2 4.0 3.9 3.9 3.8 3.7 3.6 3.5 3.6 3.5 3.6 3.6 3.7 3.6 161.6 5.21 11 3.5 321 .31 .36 10.5 MAX 12.0 MAX 3.8 3.5 3.7 3.9 8.1 40 21 7.9 6.3 11 22 57 43 16 11 8.5 7.4 6.5 7.6 8.3 .6 .0 .0 .4 .6 .6 .4 .2 .4 .8 .0 .0 .8 .0 .2 .0 .8 .0 .2 .4 6.2 4.0 5.7 3.6 5.2 4.2 5.0 3.3 5.0 3.2 4.8 3.8 4.6 4.2 4.6 3.1 2.7 —— 3.1 2.8 337.6 121.4 12 . 1 3 . 92 57 4.6 3.5 2.7 670 241 .72 .23 .75 .27 343 MIN .05 AC-FT 343 MIN .56 AC-FT 3.0 3.1 3.0 2.9 2.6 2.2 2.3 2.6 2.9 2.7 2.1 2.1 2.0 1.6 1.8 2.2 1.7 1.6 1.6 1.6 1.7 1.8 1.7 1.3 1.4 1.8 1.2 1.2 1.2 1.1 —— 60.0 2.00 3.1 1.1 119 .12 .13 7570 8690 .95 .92 .79 .78 .74 .83 .92 .94 1.1 1.3 1.3 1.7 2.2 2.6 2.2 2.4 2.6 3.2 3.5 3.7 3.3 3.8 3.8 3.5 5.3 5.4 4.1 4.0 4.0 3.9 3.4 79.17 2.55 5.4 .74 157 .15 .18 CFSM .63 CFSM .72 3.4 3.6 3.1 2.3 1.9 2.2 1.7 1.2 1.9 2.0 1.4 2.6 3.0 1.8 1.3 .94 .84 .76 .83 .95 .97 1.0 1.3 1.2 1.2 .82 .69 .73 .73 5.6 —— 51.96 1.73 5.6 .69 103 .10 .12 IN. 8.51 IN. 9.76 5.2 3.7 2.4 2.1 1.3 .82 .64 .80 .77 1.1 1.1 .85 .71 .68 .89 15 8.2 4.1 2.4 2.2 1.6 1.4 .98 .85 .87 .87 1.0 .81 l."7 1.7 1.3 68.04 2.19 15 .64 135 .13 .15 .92 .76 .69 .65 .66 .62 .75 .71 .83 .90 1.1 .99 .85 1.6 1.6 1.6 .88 .72 .66 .56 .84 3.3 4.6 1.4 .83 .66 .64 .98 .96 .84 .65 33.75 1.09 4.6 .56 67 .07 .08 .64 .61 .68 .60 .62 .56 .57 .79 .80 .94 1.1 .90 .76 .63 .69 .62 3.5 2.9 .88 2.8 1.1 1.0 5.4 3.0 1.4 .95 .81 .74 4.8 4.2 44.99 1.50 5.4 .56 89 .09 .10 RIO COAMO BASIN 50106500 RIO COAMO NEAR COAMO, PR WATER-QUALITY RECORDS LOCATION.—Lat 18«03'52-, long 66°22'10-, Hydrologic Unit 21010004, on Highway 153 bridge, 0.4 ml (0.6 km) above Rio d« la Ulna, and l.B mi (2.9 km) mouth of Comma plaEa. DRAINAGE AREA.—46.0 mi2 (119.1 km3). PERIOD Or RECORD.—Water year* 197B to current year. WATER-QUALITY RECORDS, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 06... DEC 13... FBB 1991 19... APR 24... JDN 19... ADO 21... TIME 1135 1005 1250 1335 1225 1245 DIS- CHARGE, INST. CUBIC FEET PER SECOND 81 28 12 6.4 4.8 33 SPE- CIFIC CON- DUCT- ANCE (US/CM) 658 697 576 731 740 680 PH (STAND- ARD UNITS) 8.4 8.2 8.3 8.0 8.1 8.0 TEMPER- ATURE WATER (DBG C) 28.0 24.5 27.5 32.0 31.5 33.0 TUR- BID- ITY (NTU) 1.4 1.5 2.0 2.5 1.4 2.0 OXYGEN, DIS- SOLVED (MG/L) 8.0 7.5 8.5 8.9 9.8 7.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 102 89 107 117 133 7 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 20 <10 12 27 25 28 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K140000 2100 K7400 33000 K6500 3000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 4600 370 440 2100 K130 600 DATE NOV 1990 06... DEC 13... FBB 1991 19... APR 24... JDN 19... ADO 21... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L RATIO 260 2 70 21 32 240 0 65 20 48 240 3 64 19 39 ALKA- SODIUM POTAS- LINITY AD- SIUM, WAT WH SORP- DIS- TOT PET SULFIDE TION SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L 0.9 3.0 6.0 5.3 240 250 240 250 260 260 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L <0.5 33 <0.5 38 34 (MG/L 37 57 53 DATE NOV 1990 06... DEC 13... FEB 1991 19... APR 24... JUN 19... AUG 21... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 — SILICA, DIS- SOLVED (MG/L AS SIO2) 30 -- SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 370 -- RESIDUE SOLIDS, DIS- SOLVED (TONS PER DAY) 80.9 — TOTAL AT 105 DBG. C SUS- PENDED , (MG/L) < 2 1 la 0.20 -- 0.20 28 — 30 412 -- 400 7.08 — 35.5 6 8 4 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 2.58 2.41 1.50 0.690 0.660 0.600 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.120 0.190 0.200 0.610 0.540 0.600 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 2.70 2.60 1.70 1.30 1.20 1.20 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.210 0.780 0.690 3.70 3.10 3.40 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.79 0.72 0.41 1.2 1.3 2.3 non-ideal count RIO COAHO BASIN 50106500 RIO COAMO NEAR COAHO, PR--Continued HATER-QUALITY RECORDS, WATER YBAR OCTOBBR 1990 TO 8BPTBMBBR 1991 333 DATS NOV 1990 06... DEC 13... FBB 1991 19... APR 24... JUN 19... AUG 21... DATS NOV 1990 06... DEC 13... FBB 1991 19... APR 24... JUN 19... AUG 21... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.0 1.5 1.1 4.9 4.4 5.7 IRON, TOTAL RECOV- ERABLE (UG/L AS PE) NITRO- GEN, TOTAL (MG/L AS N) 3.7 4.1 2.8 6.2 5.6 6.9 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 16 18 12 27 25 31 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.270 0.500 0.470 0.960 0.540 0.890 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 — — 1 — -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — 100 ~ — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UQ/L AS B) 60 — — 70 — -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 ~ — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 1 — — 2 — -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — 10 — ~ MBTHY- LENE BLUB ACTIVE SUB- STANCE (MG/L) 420 330 30 130 <0.10 <0.10 30 tO.010 <0.010 0.08 0.27 3§ Sd t* 33 M M <0 <0 *o *o M e •I a q Q H »3 PS in in «OM e OP e «0 *ie in 01 K Kii M M 01 * MWI SE * * 10 10 •J «J 55 9898 MO win >> I I M M «4>4 M M M e e «0 e o on ng ng SB M M MM in M H H ' ' MM •4 in 0 M Min Q Q s? n E B £c 2B ^V Q H y H O * fi "i * z 3 3 P M OP -4 wi <0<0 01 ** . 5*1" * «0 e e «J at w MMM W • • «0 M«O M w e C oi 01 OP M OP in • • in M . * •J 01 e • MM. w* in OP WIM -J M -J . . 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M°r • • Eft **° » £r & ?.«, r-^ 5g 6 "^ «09l9l OH- Ml MMM O III III U 91 00 *: •-.Ml OMI «•>« «5 \l u u en 336 RIO JACAOOAS BASIN 50110900 RIO TOA VACA ABOVB LAGO TOA VACA, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1988 to 1991. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGEi April 1988 to September 1991. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONI Maximum daily 1 mo/L several days. in, 2,510 mg/L October 21, 1990; Minimum daily Bean, SEDIMENT LOADSi Maximum daily mean, 6,340 tons (5,750 tonnes) October 21, 1990; Minimum daily mean, 0.0 ton (0.0 tonne) several days. EXTREMES FOR WATER YEARS 1989-90.-- SEDIMBNT CONCENTRATIONi Maximum daily 1 »0/L several days. SEDIMENT LOADSi Maximum daily me) 0.0 ton (0.0 tonne) few days. n, 2,510 mg/L October 21, 1990; minimum daily mean, n, 6,340 tons (5,750 tonnes) October 21, 1990; Minimum daily mean, SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 IB 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 133 82 35 25 21 36 33 66 150 126 77 71 108 244 113 154 103 116 92 65 410 107 BO 96 171 16B 115 112 97 102 B3 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER 490 337 35 32 44 124 96 261 670 553 279 269 423 1120 165 B57 327 4BO 349 235 2510 416 2B6 295 494 432 313 253 202 269 59 34B 257 3.7 2.1 2.4 30 B.B B9 642 242 61 62 133 1770 53 996 9B 256 106 57 6340 124 62 104 22B 197 101 B6 SB 92 14 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 70 62 SB 51 49 43 40 37 34 33 2B 25 24 22 20 19 20 19 IB 231 63 46 36 30 26 23 21 20 IB 17 —— 3B 32 22 21 22 2B 31 30 25 19 15 15 IB 115 41 4B 36 29 22 1410 132 2B 30 31 33 32 31 30 30 30 —— 7.1 5.4 3.3 2.B 2.9 3.2 3.3 3.0 2.2 1.7 1.1 .99 1.2 6.2 2.1 2.4 l.B 1.4 1.0 4310 2B 3.3 2.9 2.5 2.2 1.9 l.B 1.6 1.4 1.4 —— MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 17 16 16 16 15 15 14 14 14 14 14 14 12 11 11 11 10 9.3 9.0 B.B B.B B.B B.7 B.5 B.2 7.B 7.2 6.6 6.4 6.6 9.6 30 30 29 25 15 12 17 23 2B 30 30 29 34 42 4B 54 SB 60 61 57 49 3B 2B 23 20 19 IB 17 13 10 14 1.3 1.3 1.3 1.1 .62 .45 .63 .87 1.1 1.1 1.1 1.1 1.0 1.2 1.4 1.5 1.6 1.5 1.5 1.4 1.2 .93 .65 .49 .43 .39 .34 .29 .20 .IB .37 TOTAL 3391 12623.0 1203 4410.09 34B.3 2B.54 RIO JACAGOAS BASIN 50110900 RIO TOA VACA ABOVB LAOO TOA VACA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAT), WATBR YEAR OCTOBBR 1990 TO 8BPTBMBBR 1991 337 DAT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 7.9 6.6 6.0 6.1 5.6 5.4 5.4 5.1 .8 .5 .5 .6 .7 .6 .3 .5 .3 .4 .2 .1 .2 .2 .2 .1 3.8 3.8 3.7 3.8 3.6 3.7 3.6 MEAN CONCEIT- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MEAN DISCHARGE (CFS) JANUARY 20 26 20 15 15 14 38 33 19 15 11 9 9 18 32 44 46 40 36 30 24 20 13 9 12 18 23 28 33 38 38 .44 .45 .32 .23 .22 .19 .59 .43 .23 .17 .13 .11 .11 .23 .38 .49 .52 .47 .40 .31 .26 .21 .14 .10 .12 .18 .22 .27 .31 .37 .38 3.7 3.7 3.8 3.6 5.3 6.2 6.1 4.5 3.8 3.9 5.4 12 12 5.9 4.9 4.6 4.8 4.0 4.0 3.8 3.6 3.7 3.5 3.3 3.4 3.3 3.1 3.2 FEBRUARY 35 32 30 27 24 21 21 18 18 77 13 31 27 8 8 7 8 8 9 10 10 10 11 11 15 19 23 28 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MQ/L) (TONS/DAY) MARCH .35 .32 .30 .28 .39 .43 .42 .21 .19 .80 .17 2.1 1.2 .13 .11 .09 .11 .09 .09 .10 .10 .09 .09 .09 .13 .17 .19 .23 3.2 2.9 2.8 2.7 2.6 2.5 2.4 2.3 2.2 2.1 2.1 2.1 2.1 2.4 2.4 2.4 2.2 2.2 2.1 2.3 2.2 3.0 3.4 2.8 2.8 45 21 6.4 4.4 3.7 3.3 30 30 31 31 25 15 10 10 10 10 14 22 27 26 20 15 10 8 8 8 8 20 32 39 36 189 52 24 28 33 25 .27 .22 .22 .21 .17 .10 .06 .06 .06 .06 .08 .12 .16 .16 .13 .09 .05 .04 .04 .04 .05 .16 .31 .30 .27 70 4.7 .40 .32 .32 .23 TOTAL 144.3 8.98 133.1 8.97 146.0 79.40 338 HXO JACAGOAS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR—Continued 8BDHIBNT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 3.1 9.9 6.2 4.4 3.4 2.9 2.8 2.6 2.7 2.5 2.3 2.5 2.6 2.4 2.3 2.4 2.4 2.2 2.2 2.3 2.4 2.4 2.3 2.1 2.1 2.1 2.1 2.1 2.2 2.2 —— APRIL 30 32 19 11 13 18 21 21 20 14 26 43 47 48 45 40 32 38 45 53 57 51 41 30 23 22 21 20 20 15 —— MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) (CFS) (MQ/L) (TONS/DAY) MAY .24 1.8 .40 .12 .11 .13 .15 .14 .13 .09 .16 .29 .31 .29 .28 .26 .19 .22 .27 .33 .36 .32 .24 .17 .13 .12 .12 .12 .12 .09 —— 2.5 8.3 3.9 15 4.8 2.9 2.6 2.8 2.4 2.3 15 4.5 66 21 7.7 4.9 4.1 4.2 4.2 89 45 19 12 9.1 7.6 6.9 5.3 4.4 4.2 4.3 4.2 13 21 12 63 17 18 1220 38 31 18 59 14 477 121 22 7 8 10 11 637 88 19 6 3 2 2 2 3 6 7 6 .11 .58 .12 16 .24 .13 8.5 .29 .20 .11 9.5 .24 322 9.0 .53 .10 .10 .11 .12 941 14 1.1 .23 .08 .05 .04 .04 .04 .07 .08 .07 JUNE 3.8 4.5 3.6 3.1 3.1 2.8 2.6 2.4 2.2 2.1 2.1 2.7 2.2 2.2 2.4 2.2 2.1 2.0 2.0 2.5 1.9 2.1 2.1 2.2 1.8 1.9 1.9 1.9 1.9 18—— 5 4 3 3 3 2 2 3 5 12 13 6 3 3 3 4 4 3 3 3 3 4 6 12 22 29 16 15 6 167 .06 .05 .03 .02 .02 .02 .02 .02 .03 .06 .07 .04 .02 .02 .02 .02 .02 .02 .02 .01 .01 .02 .03 .06 .11 .14 .09 .08 .03 26 TOTAL 8C.1 —— 7.70 390.1 —— 1324.78 88.3 —— 27.16 RIO JACAGUAS BASIN 50110900 RIO TOA VACA ABOVB LAOO TOA VACA, PR—Continued SEDIMENT DISCHAROB, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 339 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR MEAN DISCHARGE (CFS) 8.9 6.0 5.1 4.9 4.7 4.9 7.4 36 13 5.0 3.9 3.5 3.5 3.1 3.1 81 24 10 5.7 4.3 3.4 3.0 2.9 2.6 2.6 2.4 2.4 49 8.6 3.3 2.7 320.9 6642.4 MEAN CONCEN- SEDIMENT TRATION DISCHARQE (MG/L) (TONS/DAY) JULY 10 9 7 5 5 5 15 517 29 10 9 8 6 4 4 342 43 3 3 3 3 3 3 4 5 4 3 275 33 16 10 .26 .15 .10 .07 .06 .06 .68 219 1.3 .14 .09 .07 .05 .04 .03 153 4.0 .08 .05 .04 .03 .02 .02 .03 .04 204 ,02 ,02 .88 .15 .08 584.56 19449.71 DISCHARGE (CFS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) AUGUST 2.5 2.4 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.0 1.9 1.9 1.9 35 9.9 4.3 3.8 2.6 2.0 1.9 4.8 19 26 10 5.5 4.2 8.0 5.0 3.5 3.2 2.9 7 5 4 3 3 3 4 4 5 5 5 5 5 283 31 9 6 4 3 3 15 53 51 10 5 3 14 6 1 3 3 .05 .03 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .03 140 1.6 .10 .07 .03 .02 .01 .69 5.6 4.5 .30 .08 .04 1.0 .10 .02 .03 .02 DISCHARGE (CFS) CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) SEPTEMBER 178.9 154.52 39 18 7.3 5.5 4.7 4.3 6.9 6.0 4.3 4.4 4.7 4.2 4.3 4.3 3.9 3.7 4.3 4.2 4.5 26 11 5.7 5.0 4.3 3.9 3.5 3.5 3.6 3.7 3.7 212.4 350 32 6 3 2 2 7 6 2 2 2 2 2 4 5 4 3 2 6 67 13 3 2 1 1 1 1 1 1 2 172 2.3 .14 .05 .03 .02 .26 .13 .02 .02 .02 .02 .03 .05 .06 .05 .04 .03 .08 16 .50 .05 .03 .02 .01 .00 .00 .01 .02 .02 192.01 340 RIO JACAOOAS BASIN 50110900 RIO TOA VACA ABOVE LAOO TOA VACA, PR—Continued HATER QDALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1990 01... MAY 1991 13... 20... JUL 08... 28... AOG 14... DATE OCT 1990 01... MAY 1991 13... 20... OUL 08... 28... AUO 14... TIME 1349 1431 1603 1455 1733 1700 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 47 35 25 42 55 44 DIS- CHARGE, INST. CUBIC FEET PER SECOND 598 330 537 378 247 351 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 60 44 34 57 66 56 SEDI- MENT, SUS- PENDED (MQ/L) 2590 5270 14500 7890 3250 3180 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 71 61 49 74 84 86 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 4200 4700 21000 8050 2200 3000 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 84 73 62 85 91 93 SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 19 14 10 18 16 12 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 96 89 83 96 96 98 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 30 21 12 22 32 21 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 96 97 94 99 98 99 SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM -- 25 18 32 42 28 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 99 99 99 100 100 99 341 RIO JACAOOAS BASIN 50110900 RIO TOA VACA ABOVB LAOO TOA VACA, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1990 01... 01... 21... MAY 14... 20... JDN 07... JUL 08... 28... 28... AUQ 14... 14... SEP 29... TIME 1324 1334 1022 1437 1608 1630 1440 1608 1718 1615 1640 1220 STREAM- FLOW, INSTAN- TANEOUS (CF8) SEDI- MENT, SUS- PENDED (MQ/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 8ED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 358 454 1130 16 827 150 378 365 363 80 351 5500 5300 4500 5500 1930 5900 111 9340 1930 5 21000 800 4200 4300 1520 1500 2840 2800 1.5 1300 4800 434 280 4500 1.8 41 53 82 97 50 93 50 72 65 94 67 88 342 JUQ JACAOUAS BASIN 50111500 RIO JACAOUA8 AT JUANA DIAZ, PR LOCATION.—Lat 18«03'16", long 66«30'40-, Hydrologic Unit 21010004, on Highway 14 bridge, 0.4 mi (0.6 km) west of Juana Dial plasa, and 4.0 mi (6.4 km) downstream from Lago Ouayabal. DRAINAGE AREA.--49.8 mi* (129.0km*). WATER-DISCHARGE RBCORDS PBRIOD OF RECORD.--March 1984 to current year. GAGE.—Hater-stage recorder. Elevation of gage is 131 ft (40 m), from topographic map. REMARKS.—Records poor. Flow regulation from Lago Ouayabal. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--? years (1985-91), 50.0 ft3/s (1.416 m3/s), 13.63 in/yr (346 mm/yr), 36,225 acre-ft/yr (44.7 hmVyr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 40,000 ft3/s (1,130 m>/s), Oct. 7, 1985, gage height, 29.42 ft (8.967 m) from rating curve extended above 500 ft3/s (14.2 •?/•) on basis of step-backwater analysis and logarithmic extension! minimum daily discharge, 0.68 ft3/s (0.012 m*/s), Sept. 1, 1990. EXTREMES FOR CURRENT YEAR.--Maximum discharge, 8,470 ft3/s (239 mVs), Oct. 16, gage height, 15.9 ft (4.846 m) from rating curve extended above 500 ft3/s (14.2 •?/•) on basis of step-backwater analysis and logarithmic extension; minimum daily discharge 1.5 ft*/s (0.042 mVs), May 4. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JON JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 291 440 215 138 102 111 113 152 376 887 427 255 486 738 320 848 241 235 288 301 1210 367 280 427 641 662 439 370 296 417 289 12362 399 1210 102 24520 8.01 9.23 1990 1991 250 203 197 168 175 167 162 151 132 118 104 98 95 113 108 113 112 94 84 273 100 88 44 45 39 40 46 43 39 40 —— 3441 115 273 39 6830 2.30 2.57 TOTAL 18658. TOTAL 22225 39 23 21 31 36 37 33 52 52 44 44 46 51 55 54 51 30 23 24 18 18 25 18 19 28 23 19 19 19 23 28 1003 32.4 55 18 1990 .65 .75 37 MEAN .6 MEAN 39 23 16 15 18 20 22 17 12 11 10 9.4 8.8 8.1 7.9 7.3 6.5 6.4 7.3 8.1 8.3 8.3 10 29 35 38 38 17 8.8 7.7 7.0 479.9 15.5 39 6.4 952 .31 .36 51.1 60.9 6.6 7.6 6.9 6.7 27 43 39 28 21 15 21 15 23 11 7.7 9.6 11 11 12 28 24 22 20 16 14 10 8.5 8.1 —— 472.7 16.9 43 6.6 938 .34 .35 MAX 1210 MAX 1210 7.7 10 10 9.5 8.1 7.9 7.2 6.1 5.3 5.3 5.4 4.8 4.5 6.7 6.8 5.7 5.7 5.5 4.2 3.9 4.2 5.6 4.9 3.5 3.1 11 7.8 3.8 4.5 4.3 3.2 186.2 6.01 11 3.1 369 .12 .14 MIN .68 MIN 1.5 3.4 2.9 2.6 2.7 3.0 3.4 3.1 2.9 2.9 2.8 3.1. 3.1 2.8 2.8 3.1 3.2 3.2 3.4 3.5 3.5 3.6 3.7 3.7 3.1 3.7 4.1 3.2 2.9 3.1 3.1 —— 2.9 1.7 1.7 1.5 1.7 1.9 1.9 3.0 4.0 2.4 11 3.5 2.6 2.8 2.6 4.9 3.2 3.8 4.2 3.4 3.2 3.7 3.5 3.4 3.3 3.5 3.5 3.3 2.8 2.8 2.9 95.6 100.6 3.19 4.1 2.6 190 .06 .07 AC-FT 37010 AC-FT 44080 3.25 11 1.5 200 .07 .08 CFSM CFSM 2.9 3.5 4.6 3.2 3.0 2.7 2.5 2.6 2.4 2.3 2.4 2.9 2.8 2.4 2.7 4.2 4.3 4.0 e3.7 e5.6 e6.6 e8.0 •8.8 •8.2 •9.0 elO elO •13 •23 •35—— 196.3 6.54 35 2.3 389 .13 .15 1.03 IN. 1.22 IN. •28 •19 •20 •21 •18 •20 •54 •140 •54 •22 •21 •23 •23 •29 •82 •454 •130 •62 •17 •9.0 •6.0 •4.3 •3.4 •4.3 •3.7 •3.5 •50 •290 •74 •30 •23 1738.2 56.1 454 3.4 3450 1.13 1.30 13.94 16.60 •8.1 •8.2 23 24 43 60 67 49 33 21 16 25 27 5.0 10 19 53 35 19 5.0 2.2 97 125 55 16 5.3 16 57 42 34 23 1022.8 33.0 125 2.2 2030 .66 .76 5.4 39 17 14 12 9.0 9.1 9.0 4.7 4.3 3.7 3.6 3.3 3.3 3.2 11 7.5 5.2 34 106 140 103 77 86 •79 •74 •68 •64 •66 •66—— 1127.3 37.6 140 3.2 2240 .75 .84 Estimated A A A RIO JACAOUAS BASIN 50111500 RIO JACAOUAS AT JUANA DIAZ, PR—Continued WATER QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS APRIL 1984 TO SEPTEMBER 1985, OCTOBER 1987 TO CURRENT YEAR STRBAMFLOW, SPECIFIC CON- TEMPERA- STRBAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TORE DATE TIME INSTANTANEOUS DUCTANCE TORE (CFS) (UMHOS) (DBG C) (CFS) (UMHOS) (DBG C) JAN. 29 1133 8.62 400 24.0 MAY 20 1019 3.11 510 24.0 MAR. 12 1138 4.91 430 24.0 JUNE 18 1259 3.67 440 24.0 APR. 24 1342 3.02 410 24.0 344 THIS PAGE WAS LEFT BLANK INTENTIONALLY .-/-•• ^••x/v- vw,...-^ EXPLANATION SURFACE-WATER STATION AND NUMBER QUALITY-OF-WATER STATION AND NUMBER WELL AND WELL NUMBER 125780 LAKE-ELEVATION STATION 0123458 34 Figure 23.--South coast river basins the Rio Inab6n to Rio Loco basins. CO 346 RIO INABON BASIN 50112500 RIO INABON AT REAL ABAJO, PR LOCATION.~Lat 18°05'10", long 66°33'46", Hydrologie Unit 21010004, at bridge on private road, off Highway 511 at Hacienda La Concordia, 0.4 mi (0.6 km) upstream from diversion canal, 0.5 mi (0.8 km) north of Real Aba jo, and 6.1 mi (9.8 km) northeast of Plaza Degetau in Ponce. DRAINAGE AREA.--9.70 mi* (25.12 km*). MATER-DISCHARGE RECORDS PERIOD OF RECORD. — 1962-63 (annual low-flow measurements only), February to June 1964 (monthly measurements only), July 1964 to July 1970, April 1971 to current year. GAGE. — Water-stage recorder. Elevation of gage is 410 ft (125 m) , from topographic map. Prior to April 1971 nonrecording gage and crest-stage gage at different datum. REMARKS. — Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE. --25 years (1965-69, 1972-91), 18.6 ftVs (0.527 m'/s), 26.04 in/yr (661 mm/yr) , 13,480 acre-ft/yr (16.6 nmVyr); median of yearly mean discharges, 18 ft'/s (0.51 mVs) , 13,000 acre-ft/yr (16 hmVyr) . EXTREMES FOR PERIOD OF RECORD. — M*y1™^ discharge, 19,000 ftVs (538 mVs), Oct. 7, 1985, gage height, 25.3 ft (7.711 m), datum then in use, from floodmark, from rating curve extended above 30 ftVs (0.85 mVs) on basis of contracted opening and flow-over-road measurements of peak flowi minimum daily discharge, 0.80 ftVs (0.023 m'/s), July 23, 1977. EXTREMES FOR CURRENT YEAR. --Peak discharges greater than base discharge of 500 ftVs (14.2 mVs), and maximum (*)t Discharge (ftVs) (m?/ Gage height (ft) (m) Date Time Oct. 21 0925 668 18.9 8.04 2.450 Minimum daily discharge, 3.2 ftVs (0.091 m>/s), Apr. 26. Date July 16 Time 1145 Discharge (ftVs) (mVs) *772 28 Gage height (ft) (m) *8.93 2.722 DISCHARGE, CUBIC FEET PER SECOND, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. OCT 82 93 54 30 27 30 36 44 64 94 99 68 115 108 63 61 46 39 50 66 180 88 53 76 127 115 93 104 87 131 114 2437 78.6 180 27 4830 8.10 9.35 NOV 86 68 57 54 61 52 43 39 36 33 31 29 27 26 25 25 24 23 29 45 34 32 32 28 39 37 28 24 21 20 1108 36.9 86 20 2200 3.81 4.25 DEC 19 18 19 17 16 15 15 14 14 13 13 13 12 12 15 14 12 10 10 9.9 9.7 9.2 9.1 8.8 8.8 8.4 8.1 7.7 7.1 7.0 11 375.8 12.1 19 7.0 745 1.25 1.44 JAN 9.2 7.6 7.2 6.6 6.6 6.5 6.6 6.8 6.5 5.8 5.5 5.4 5.3 5.1 5.5 6.1 5.6 5.6 5.4 5.7 6.0 6.0 6.2 e6.6 e5.5 eS.O e4.8 e4.7 5.4 5.8 6.0 186.6 6.02 9.2 4.7 370 .62 .72 FEB 7.4 6.8 7.1 8.2 12 17 13 8.5 7.6 7.7 9.7 7.6 7.9 7.4 7.2 9.0 7.5 6.8 6.6 6.4 6.0 5.8 5.5 5.5 5.5 5.5 5.4 5.4 216.0 7.71 17 5.4 428 .80 .83 MAR 5.4 4.9 5.3 5.9 6.5 6.3 5.8 5.4 5.2 4.8 5.1 5.0 5.0 .8 .7 .6 .6 .8 5.0 5.4 5.1 5.1 7.0 4.6 4.1 61 31 13 9.5 7.9 6.6 259.4 8.37 61 4.1 515 .86 .99 APR 5.8 16 15 16 13 16 12 7.1 5.6 5.5 5.2 5.2 4.6 4.5 4.7 5.0 4.2 3.7 3.5 3.5 3.7 3.9 4.0 3.7 3.4 3.2 3.4 7.5 3.5 3.5 MAY 7.7 8.0 12 e!7 ell e9.9 7.6 13 10 7.1 20 19 18 14 9.6 JUN 5.6 e7.0 e6.2 e5.4 e5.2 eS.O e4.8 e4.8 e4.7 e4.6 e4.5 e9.0 e5.6 e8.9 e7.8 7.2 5.5 8.2 7.6 3 4 8.2 5.9 .9 .6 .6 .9 .7 .9 5.4 5.6 e6.0 e4.7 eS.O e23 e!6 e50 e21 e!7 e!3 ell 12 10 9.9 8.7 23—— CAL YR 1990 WTR YR 1991 TOTAL 6214.53 TOTAL 7315.40 KftAN 17.0 MEAN 20.0 MAX 180 MAX 180 MIN .93 MIN 3.2 191.9 6.40 16 3.2 381 .66 .74 AC-FT 12330 AC-FT 14510 293.1 9.45 20 4.6 581 .97 1.12 CFSM 1.76 CFSM 2.07 322.4 10.7 50 4.5 639 1.11 1.24 JUL 13 13 11 10 10 11 29 47 42 18 14 12 13 11 11 115 44 46 28 16 12 14 12 10 9.1 10 11 27 19 14 e!8 670.1 21.6 115 9.1 1330 2.23 2.57 AUG e21 16 14 12 e!8 e!3 14 13 11 11 9.6 9.5 11 e32 e!6 44 28 20 17 36 25 66 48 47 41 27 28 30 24 20 18 740.1 23.9 66 9.5 1470 2.46 2.84 SEP 26 20 IX 15 13 11 16 13 14 13 12 11 13 11 12 20 21 16 26 35 27 19 17 14 13 12 11 32 21 14 515 17.2 35 11 1020 1.77 1.98 IN. 23.83 IN. 28.05 Estimated 347 RIO BUCANA BASIN 50113800 RIO CBRRILLOS ABOVE LACK) CERRILLOS NEAR PONCE, PR LOCATION.«Lat 18007'01-, long 66°36'17", Hydrologic Dnit 21010004, on right bank, 0.3 ml (0.5 km) downstream from confluence with Rio San Patricio, 0.1 mi (0.2 km) southwest of Hwy 139 and 2.4 mi (3.7 km) northwest of Maraguex. DRAINAGE AREA.-- 15.4 mi* (39.9 km*). WATER-DISCHARGE RECORDS PERIOD OF RBCORD.—December 1988 to current year. GAGE.—Water-stage recorder and crest-stage gage. Elevation of gage is 720 ft (210 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor, satellite telemetry at station. Gage-height and precipitation EXTREMES FOR PERIOD OF RBCORD.--Maximun discharge, 2,500 ft'/» (70.8 mVs), Sept. 25, 1990, estimated based on mean daily discharge correlation with nearby station 50115000; minimum discharge, 3.3 ft1/* (0.093 mV*)/ Aug. 16-18, 20, 21, 1990. EXTREMES FOR CURRENT YEAR..—Peak discharges greater than base discharge of 600 ft1/* (17.0 •?/») and (*)« Date Oct. 2 Oct. 14 Oct. 16 Oct. 21 Time 1515 1515 1530 0930 Discharge (ftVs) (mVs) 737 621 624 777 20.9 17.6 17.7 22.0 Gage height (ft) (m) 3.71 3.42 3.35 3.80 1.131 1.042 1.021 1.158 Date Oct. 25 Aug. 16 Aug. 20 Sept. 28 Time 2000 1445 1445 1515 Discharge (ftVs) (mVs) *1,070 628 603 699 30.3 17.8 17.1 19.9 Gage height (ft) (m) *4.40 3.36 3.37 3.62 1.341 1.024 1.027 1.103 Minimum discharge, 4.8 ft'/s (0.14 mVs), Mar. 10-26. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALOBS DAY OCT NOV DEC JAN FEE MAR APR MAY JON JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX KIN AC-FT CFSM IN. CAL YR WTR YR M 188 137 71 51 46 58 59 87 90 118 129 249 229 155 166 140 111 118 142 345 162 104 141 309 278 263 246 195 170 136 4787 154 345 46 9500 10.0 11.56 114 92 78 76 92 77 65 56 51 46 42 40 37 36 33 35 32 30 34 61 43 50 47 39 51 39 32 28 26 24 —— 1506 50.2 114 24 2990 3.26 3.64 1990 TOTAL 10752.0 1991 TOTAL 12198.5 24 25 24 22 22 21 21 20 20 20 19 18 19 21 28 20 17 17 16 15 15 15 15 15 15 14 13 14 12 13 15 565 18.2 28 12 1120 1.18 1.36 MEAN MEAN 14 12 12 12 12 12 12 12 12 11 11 11 11 10 11 10 9.6 9.4 9.2 9.2 9.2 9.2 9.2 9.1 8.7 8.7 8.7 8.3 8.3 8.2 7.9 317.9 10.3 14 7.9 631 .67 .77 29.5 MAX 33.4 MAX 8.3 8.2 8.5 8.3 13 13 11 9.2 8.8 10 11 13 17 9.2 8.0 7.4 7.7 .6 .9 .6 .3 .3 5.7 5.6 5.6 5.6 5.7 5.1 —— 237.6 8.49 17 5.1 471 .55 .57 345 MIN 345 MIN 5.6 5.2 5.2 5.1 5.5 5.6 5.4 5.2 5.4 5.3 5.1 5.1 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 5.7 5.8 4.8 4.8 82 19 8.1 6.6 6.0 6.0 255.7 8.25 82 4.8 507 .54 .62 3.3 AC-FT 4.8 AC-FT 5.7 14 13 20 15 27 18 9.6 8.1 7.4 7.1 7.2 6.7 6.7 6.7 6.6 6.0 6.0 6.0 6.0 6.0 6.0 5.7 5.7 5.7 5.7 5.7 5.4 5.4 11 —— 265.1 8.84 27 5.4 526 .57 .64 21330 24200 8.8 6.7 7.6 43 24 14 8.7 14 16 12 28 21 13 11 11 10 8.9 16 16 23 18 17 12 11 9.9 10 9.1 8.3 8.3 8.3 8.8 433.4 14.0 43 6.7 860 .91 1.05 CFSM 1.91 CFSM 2.17 9.3 11 9.2 8.2 8.3 7.9 7.6 7.4 7.4 7.4 7.0 14 9.2 14 12 8.1 7.4 35 25 16 55 27 14 11 10 9.4 9.1 9.2 8.7 61 —— 445.8 14.9 61 7.0 884 .96 1.08 IN. 25. IN. 29. 26 18 21 18 13 12 35 41 26 16 13 12 12 ell elS e!30 e40 81 45 23 19 18 V> 15 14 13 13 31 17 15 47 827 26.7 130 11 1640 1.73 2.00 99 47 30 40 18 34 e!4 29 elSO 26 e86 25 31 24 18 24 16 24 15 25 16 23 16 21 16 23 17 22 60 20 27 20 62 50 42 33 23 23 16 36 98 57 95 34 163 27 113 25 72 22 107 21 86 20 72 37 55 81 43 40 36 26 33 —— 1646 912 53.1 30.4 163 81 14 20 3260 1810 3.45 1.97 3.98 2.20 Estimated 348 RIO BUCANA BASIN 50113800 RIO CBRRILLOS ABOVE LAQO CBRRILLOS NEAR PONCE, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.--JANUARY TO JUNE 1991. STRBAMFLOW, SPECIFIC CON- TEMPERA- DATE TINE INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DBG C) DATE TIME JAN. 11 1235 APR. 25 1421 11.0 5.67 280 290 22.0 24.0 MAY 22 1057 JUNE 20 1413 STRBAMFLOW, INSTANTANEOUS (CFS) 18.7 15.0 SPECIFIC CON- TBMPBRA- DUCTANCE (UMHOS) 210 200 TURE (DBQ C) 24.0 24.0 RIO BUCANA BASIN 348 50114000 RIO CBRRILLOS NEAR PONCE, PR LOCATION.—Lat 18°04'15", long 66°34'51", Hydrologic Unit 21010004, on right bank off Highway 139, 0.8 mi (1.3 km) below Lago Cerrillos Dam, 2.3 mi (3.7 km) upstream from Quebrada Ausubo and 4.6 mi (7.4 km) northeast of Plaza Degetau in Ponce. DRAINAGE AREA.--17.8 mi2 (46.1 km2 ), excludes 17.4 mi2 (45.1 km2), upstream from Lago Cerrilloi Dam. WATER-DISCHARGE RECORDS PERIOD OF RECORD.—February to April 1964 (monthly measurements only), May 1964 to June 1985, July 1985 to April 1991 (semi-monthly measurements only), Hay to September 1991. GAGE.—Water-stage recorder. Datum of gage is 253.10 ft (77.145 m), above mean sea level. Prior to March 22, 1977 at site 0.15 mi (0.24 km) upstream and datum 9.90 ft (3.018 m) higher. REMARKS.--Records poor. Flow regulated by Lago Cerrillos Dam since May 1991. Gage-height and precipitation satellite telemetry at station. Prior to June 1985 some low-flow regulation by construction upstream. AVERAGE DISCHARGE.—20 years (1965-84), 35.1 ftVs (1.994 mVs), 26.78 in/yr (680 mm/yr), 25,430 acre-ft/yr (31.4 haVyr); median of yearly mean discharges, 33 ft'/s (0.93 mVs), 23,900 acre-ft/yr (29 hmVyr), prior to Lago Cerrillos Dam construction. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 22,400 ftVs (634 mVs), Sept. 16, 1975, gage-height, 11.2 ft (3.414 m), site and datum then in use, from floodmarks, from rating curve extended above 150 ft'/s (4.25 m*/s) on basis of slope- area measurement of peak flow} minimum discharge, 2.2 ftVs (0.062 mVs), May 28, 1967, prior to Lago Cerrillos Dam construction. EXTREMES FOR CURRENT PERIOD.--Maximum discharge, 297 ftVs (8.41 mVs), July 16, gage-height 3.34 ft (1.018 m), from rating curve extended above 100 ftVs (14.2 m?/s) on basis of step-backwater analysis} ••<"<"•"- daily discharge, 6.6 ftVs (0.187 mVs), May 2. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR. MAY JUN JUL AUG SEP 1 e9.0 10 33 42 14 2 e6.6 10 15 17 13 3 e7.4 10 14 15 13 4 e42 9.0 20 13 13 5 e25 9.0 14 39 12 6 e!5 9.7 12 39 13 7 e8.6 7.3 21 18 12 8 e!4 8.4 35 16 11 9 e!6 8.2 29 14 12 10 e!2 7.3 16 13 13 11 e30 8.2 14 12 13 12 e21 13 12 12 13 13 e!3 14 12 12 15 14 ell 11 11 37 14 15 ell 16 14 26 14 16 e9.8 11 106 45 17 17 e8.8 11 42 35 14 18 e!6 17 62 25 15 19 e!6 35 54 17 14 20 e27 24 27 33 14 21 e23 29 19 46 15 22 e22 42 18 36 15 23 e!2 16 17 22 17 24 ell 13 15 25 20 25 e9.8 10 13 23 19 26 e9.8 10 13 18 20 27 e9.0 11 13 13 21 28 e8.2 9.0 23 11 22 29 e7.6 12 29 13 20 30 7.9 34 13 14 25 31 9.7 —— 26 14 —— TOTAL 449.2 435.1 762 715 463 MEAN 14.5 14.5 24.6 23.1 15.4 MAX 42 42 106 46 25 MIN 6.6 7.3 11 11 11 AC-FT 891 863 1510 1420 918 CFSM .81 .81 1.38 1.30 .87 IN. .94 .91 1.59 1.49 .97 e Estimated 350 RIO BUCANA BASIN 50114000 RIO CERRILLO8 NEAR PONCB, PR Location.--Lat 18°04'15-, long 66°34'51", Hydrologic unit 21010004, on right bank off Highway 139, (3.7 1m) upstream from Quebrada Ausubo and 4.6 mi (7.4 km) northeast of Plaza Degetau in Pone*. DRAINAGE ARBA.—17.8 mia (46.1 km2) WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1964 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 2.3 mi DATE OCT 1990 19... DEC 12... FBB 1991 06... APR 10... JUN 05... AOG 29... TIME 1145 1145 0830 1100 1345 1535 DIS- CHARGE, INST. CUBIC FEET PER SECOND 150 22 18 10 4.4 14 SPE- CIFIC CON- DUCT- ANCE (OS/CM) 291 313 314 297 326 232 PH (STAND- ARD UNITS) 8.1 8.5 8.2 8.5 8.5 8.3 TEMPER- ATURE WATER (DBG C) 24.0 24.5 20.0 24.5 31.5 28.5 TUR- BID- ITY (NTU) 120 8.6 29 2.8 7.5 4.3 OXYGEN, DIS- SOLVED (MG/L) 8.4 8.8 8.8 8.4 7.9 6.7 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 99 105 97 100 107 86 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 30 <10 23 10 22 16 COLI- FORM, FECAL, 0.45 UM-HF (COLS./ 100 ML) 34000 K700 K1900 310 K50 470 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 67000 K150 5500 K100 K50 M220 DATE OCT 1990 19... DEC 12... FBB 1991 06... APR 10... JUN 05... AUG 29... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CAC03 110 130 120 33 42 35 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MQ) AS NA) SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT FBT SULFIDE SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS K) CACO3 AS S) AS SO4) AS CL) 6.6 5.5 8.5 0.4 1.0 100 <0.5 16 150 150 6.9 11 0.4 1.0 130 <0.5 18 9.3 130 6.8 10 0.4 1.3 140 -- 19 7.4 SOLIDS, DATE OCT 1990 19... DEC 12... FBB 1991 06... APR 10... JUN 05... AUG 29... FLUO- RIDB, DIS- SOLVED (MQ/L AS F) 0.20 -- -- <0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 24 — — 21 — 22 SUM OF CONSTI- TUENTS, DIS- SOLVED (MQ/L) 155 -- -- 187 — 162 RESIDUE SOLIDS, V3TAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+N03 AMMONIA ORGANIC (TONS PER DAY) 1- )ED I/L) 287 17 77 3 15 192 TOTAL (MG/L AS N) 0.930 0.380 0.780 — 0.580 0.470 TOTAL (MG/L AS N) 0.070 0.020 0.020 <0.010 0.010 0.010 TOTAL (MG/L AS N) 1.00 0.400 0.800 0.230 0.590 0.480 TOTAL (MG/L AS N) 0.080 0.020 0.030 <0.010 0.030 0.130 TOTAL (MG/L AS N) 0.22 — 0.87 — 0.27 0.27 non-ideal count RIO BUCANA BASIN 50114000 RIO CBRRILLOS NEAR PONGS, PR—Continued HATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 351 DATE OCT 1990 19... DEC 12... PEB 1991 06... APR 10... •TON 05... AUQ 29... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MQ/L AS N) 0.30 <0.20 0.90 0.50 0.30 0.40 NITRO- GEN, TOTAL (MQ/L AS N) 1.3 — 1.7 0.73 0.89 0.88 NITRO- GEN, TOTAL (MQ/L AS N03) 5.8 -- 7.5 3.2 3.9 3.9 PHOS- PHORUS ARSENIC TOTAL TOTAL (MQ/L (UG/L AS P) AS AS) 0.190 <1 0.060 0.070 0.020 <1 0.050 0.040 BARIUM, TOTAL RECOV- ERABLE (UQ/L AS BA) 200 — — <100 — — CHRO- BORON, CADMIUM MIUM, TOTAL TOTAL TOTAL RBCOV- RECOV- RECOV- ERABLE BRABLE BRABLE (UG/L (UG/L (UQ/L AS B) AS CD) AS CR) <10 <1 5 __ __ 20 3 <1 __ — COPPER, TOTAL RECOV- ERABLE (UQ/L AS CU) 30 — — <10 — — DATE OCT 1990 19... DEC 12... PEB 1991 06... APR 10... JUN 05... AUQ 29... IRON, TOTAL RBCOV- BRABLE (UQ/L AS PE) LEAD, TOTAL RECOV- ERABLE (UQ/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UQ/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HO) SELE- NIUM, TOTAL (UQ/L AS SB) SILVER, TOTAL RECOV- ERABLE (UQ/L AS AQ) ZINC, TOTAL RECOV- ERABLE (UO/L AS ZN) CYANIDE TOTAL (MQ/L AS CN) PHENOLS TOTAL (UQ/L) MBTHY- LENB BLUE ACTIVE SUB- STANCE (MQ/L) 10000 350 12 370 50 <0.10 <0.10 <1 <1 <1 <1 30 <0.010 <0.010 <0.01 0.02 hi. e e e» <• n n n n H H out n t» M t» r>e» w M 00 09 d O O W «• • n H r- * 1/1 e <* H e . • H n d H H 3 * O A «o 1/1 « A r-1/1 r-1/1 d eeer>«o •• vo H H vo g r-H H H M m dH H H H H H M A «0 A W d A AH«H« d 1/1 e A r- A I/IHHOOWOO d I/I U) H H n H H H I/I d • • n w •• •• i* dd I/I VO VO A d H d H H HH H A « A d dOOHUtf) Wn<«A<« 'dHdHH ••HHH e e e Hf. I/I MM «* 383 e e A n n e OHH e e e 00 I/I A W A «0 A a w oo w 1/1 HI/IH Af» A 00 •• m «H H o w «o A . w H w e n U) H •• H • • HI/I m d d oo m w ut O O A A O «0 W . . • • «o . H w r- SB SB H^ 1/10 . . HH S3 M M I H A I/I i I H HI r< • • H vo r- 1/1 w w i o«0dww A e oo 1/1 H •• VO W WU) > w M i m o» o» «» o «o m o « ...i * 1/1 m • r- m <« •* vo iwwi r-. •*!/! • • MM 40 A •• H r- oo o vo n r- vo i/ir-dHm «O«OU>WA a w A •• n •• vo vo H vo i/i m • • d • n i/i vo r-r-wwoo r- w M 1/11/1 1/11/11/11/11/1 1/11/1 w w w w r- A r- w 1/1 w A H A «o H n H ut oo * * W d H H d H H •• A U) W M A d I/I e w «o i i i • • • i ii «or>r> i i i oo i/i n vo o vo «» d H r> w • • SB SB ss 33333 33333 i I/I H <• <• H , H • r- * 1/1 «o r- r- w M in 1/1 1/1 M M «• o r- A A • M H oe r- oo I/I A H . • H M I/I « M I/I «0 «d IA w 1/1 e •• w W I/I A W A «n « I/IH «o d W d 0 «0 dHHH 40 ^ d d A r> w d r> * HHd r- A n«o n p. W W I/I I/I OH e o « n n A «o 1/1 I/IH •• e ut 1/1 1/1 « M e H H A 1/1 w r- r- H e «o w r>«o 1/1 w w w H M r- o» I/I W •• U) M H H •• W A A I/I 1 W •• M M M 1 1 «0 H A A I/I •• e «or> 1/1 1/1 « H r- «o H i/i o i/i i/i •9 0 I/I fH •• M «0 d H M •• . . m w •• •• d d W W 00 • M M I/I I/I (•) H • W H d d « H «n d d W d «• r> oo d d 1%n 0 H A A A A H H « 1/1 wr-«OAO RIO PORTUGOBS BASIN 50115000 RIO PORTOOUBB NBAR PONCB, PR 353 LOCATION.—Lat 18°04'45-, long 66°38'01-, Bydrologic Unit 21010004, on right bank 30 ft (9 m) up*tream tram bridge on Highway 504, 0.2 mi (0.3 km) upstream from small unnamed tributary, 4.4 mi (7.1 km) upstream from Rio Chiquito, and 4.7 mi (7.6 km) north of Plaza Degetau in Ponce. DRAINAGE ARBA.—8.82 mi* (22.84 km*). WATER-DISCHARGE RECORDS PERIOD OF RBCORD.—February to June 1964 (monthly measurements only), July 1964 to current year. GAGE.—Water-atage recorder. Elevation of gage ia 470 ft (143 m), from topographic map. Prior to Dec. 4, 1964, non-recording gage at same aite and datum. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Some low-flow regulation due to unknown activity upstream. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--27 years (1965-91), 19.0 ftj/s (0.538 mVs), 29.25 in/yr (743 mm/yr), 13,760 acre-ft/yr (17.0 hmVyr); median of yearly mean discharges, 18.8 ftVs (0.53 mVs), 13,600 acre-ft/yr (17 hm'/yr). EXTREMES FOR PERIOD OF RBCORD.--Maximum discharge, 21,000 ftVs (595 mVs), Oct. 7, 1985, gage height, 20.2 ft (6.157 m), from floodmarks at downstream side of bridge, from rating curve extended above 150 ftVs (4.25 mVs) on basis of slope-area measurement of peak flow; •«<«<•»• discharge, 1.0 ftVs (0.028 m'/s), May 29, 1973. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 800 ftVs (22.6 mVs) and maximum (*)t Date Oct. 2 Oct. 14 Time 1540 1600 Discharge (ftVs) (mVs) 1,330 1,040 37.7 29.4 Gage height (ft) (m) 6.96 2.121 6.30 1.920 Date Oct. 25 Time 1945 Discharge (ftVs) (mVs) Gage height (ft) (m) •1,920 54.4 •8.01 2.441 Minium discharge, 2.5 ftVa (0.071 mVs), Apr. 27-30. DISCHARGE, CUBIC FBBT PBR SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JON JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 61 146 69 35 25 21 36 43 68 67 76 101 198 216 86 119 114 83 82 83 315 112 78 118 313 236 e!70 e!60 e!50 e!20 elOO 3601 116 315 21 7140 13.2 15.19 1990 1991 e86 e74 e60 e52 e48 e55 e48 e43 e37 e34 e31 e28 e26 23 21 22 20 19 19 58 35 31 23 22 35 30 22 19 17 16 —— 1054 35.1 86 16 2090 3.98 4.45 TOTAL 7326.9 TOTAL 7331.8 15 15 15 13 13 12 12 11 11 11 11 10 11 12 24 14 11 10 9.4 9.7 9.5 8.9 8.9 8.9 8.4 8.1 8.3 8.1 8.1 8.0 10 345.3 11.1 24 8.0 685 1.26 1.46 MEAN MEAN 8.6 7.5 7.4 7.4 7.1 6.9 7.1 6.9 6.8 6.8 6.7 6.4 6.4 6.2 6.2 6.2 5.9 6.1 5.9 5.9 5.9 5.9 5.9 5.8 5.3 5.1 5.1 5.2 4.9 4.9 4.8 193.2 6.23 8.6 4.8 383 .71 .81 20.1 MAX 20.1 MAX 5.0 4.6 5.1 7.4 14 7.7 8.2 5.5 5.3 5.9 7.4 16 19 10 7.2 7.2 7.1 5.7 5.6 5.4 5.2 5.1 5.1 5.3 5.1 5.0 4.6 4.8 —— 199.5 7.12 19 4.6 396 .81 .84 315 MIN 315 MIN .7 .6 .6 .7 .2 .0 .6 .2 .3 .2 .2 .6 .2 .2 .2 4.0 3.8 3.9 3.9 3.8 3.8 4.4 5.0 3.9 3.8 60 21 6.8 4.9, 4.1 3.8 208.4 6.72 60 3.8 413 .76 .88 1.5 AC-FT 2.5 AC-FT 3.7 6.4 12 4.9 5.6 17 15 6.3 4.9 4.3 4.3 4.0 4.0 3.7 3.6 3.7 3.2 3.2 3.3 3.1 3.0 3.0 2.8 2.8 3.2 2.8 2.6 2.5 2.5 3.0 —— 144.4 4.81 17 2.5 286 .55 .61 14530 14540 5.5 2.8 2.6 21 22 14 6.5 23 40 26 13 16 8.8 6.6 5.4 5.1 4.7 12 12 8.3 7.3 9.2 6.5 5.3 5.1 5.8 5.8 4.6 4.2 4.2 4.7 318.0 10.3 40 2.6 631 1.16 1.34 CFSM 2.28 CFSM 2.28 5.3 4.5 4.5 4.0 3.9 3.8 3.9 3.7 3.6 3.4 3.3 4.8 4.1 4.6 6.0 3.5 3.4 5.8 7.3 4.5 10 7.6 4.3 3.9 3.6 3.5 3.7 4.7 4.2 9.0 —— 142.4 4.75 10 3.3 282 .54 .60 IN. 30. IN. 30. 7.3 4.4 19 15 6.0 4.7 16 13 6.3 5.2 4.4 4.3 4.2 3.9 4.8 46 20 35 25 12 7.8 8.2 7.8 5.7 5.0 4.8 4.6 8.1 8.1 5.2 12 333.8 10.8 46 3.9 662 1.22 1.41 90 92 12 6.2 5.8 5.0 53 30 11 8.3 6.6 5.9 5.4 5.2 5.2 9.0 7.2 5.4 25 15 7.4 36 36 75 48 34 39 25 15 12 9.9 8.8 7.8 575.1 18.6 75 5.0 1140 2.10 2.43 7.1 6.7 6.4 5.9 5.4 5.2 5.4 5.2 5.7 5.4 .8 .6 .4 .2 .5 9.1 14 6.1 11 15 13 10 8.8 7.2 6.3 6.4 5.9 8.3 8.5 6.2 216.7 7.22 15 4.2 430 .82 .91 Estimated 354 RIO PORTUQUBS BASIN 50115000 RIO PORTUOUBS NEAR PONCB, PR—Continued MATER-QUALITY RECORDS PERIOD OF RECORD.--Water yeari 1964 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 19... DBC 12... FEB 1991 06... APR 10... JUN 05... ADO 29... TUB 0940 1005 1035 0855 1040 1345 DIS- CHARGE, INST. CUBIC FEET PER SECOND 81 11 16 4.1 4.2 10 SPE- CIFIC CON- DUCT- ANCE (US/CM) 233 326 313 305 310 260 PH (STAND- ARD UNITS) 8.3 8.2 8.2 8.4 8.6 7.9 TEMPER- ATURE HATER (DBG C) 22.0 21.5 21.0 21.5 25.0 27.0 TUR- BID- ITY (NTU) 80 1.3 1.5 2.2 1.0 18 OXYGEN, DIS- SOLVED (MG/L) 8.5 9.1 8.9 9.0 10.5 6.3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 99 102 100 100 127 79 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 12 <10 13 <10 12 34 COLI- FORM, FBCAL, 0.45 UM-MF (COLS./ 100 ML) K910 4900 4000 490 280 82 STREP- TOCOCCI FBCAL, (COLS. PER 100 ML) 2600 240 3100 K260 260 240 DATE OCT 1990 19... DBC 12... FEB 1991 06... APR 10... JUN 05... AUG 29... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DI8- (MG/L TOT FLD SOLVED AS MAGNE- SIUM, SODIUM, DI8- DIS- SOLVED SOLVED MG/L AS (MG/L (MG/L 100 0 32 140 0 46 87 0 27 (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) 5.3 7.9 7.3 11 4.8 7.7 SODIUM AD- SORP- TION RATIO ALKA- POTA8- LINITY SIUM, NAT MB DI8- TOT FBT SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L CHLO- SULFATB RIDE, DI8- DIS- SOLVED SOLVED (MG/L 0.3 1.0 0.4 1.3 0.4 1.4 100 150 140 140 140 70 <0.5 <0.5 7.5 7.4 7.0 (MG/L AS K) CAC03 AS 8) AS SO4) AS CL) 8.6 9.2 6.5 DATE OCT 1990 19... DEC 12... FEB 1991 06... APR 10... JUN 05... AUG 29... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- <0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 22 — — 19 — 20 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 144 -- -- 185 — 125 SOLIDS, DIS- SOLVED (TONS PER DAY) 31.5 — — 2.07 — 3.38 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 37 <1 6 1 <1 10 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.39 0.980 1.39 — — 0.620 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.020 0.010 <0.010 <0.010 0.020 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.40 1.00 1.40 0.810 0.350 0.640 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.030 0.070 <0.010 <0.010 0.020 0.050 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.47 0.43 — — 0.28 0.35 non-Ideal count RIO PORTUGUES BASIN 50115000 RIO PORTUOOBS NEAR PONCB, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBBR 1990 TO SBPTBMBBR 1991 355 DATE OCT 1990 19... DBC 12... FBB 1991 06... APR 10... JUN 05... AUG 29... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.50 0.60 0.20 0.30 0.40 NITRO- GEN, TOTAL (MG/L AS N) 1.9 1.5 2.0 1.0 0.65 1.0 NITRO- GEN, TOTAL (MG/L AS NO3) 8.4 6.6 8.9 4.5 2.9 4.6 PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.040 <1 0.060 0.040 0.040 <1 0.030 0.080 BARIUM, BORON, TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS BA) AS B) <100 <10 — — <100 40 — — CHRO- CADMIUM MIUM, COPPER, TOTAL TOTAL TOTAL RBCOV- RBCOV- RECOV- ERABLE BRABLB BRABLB (UG/L (UG/L (UG/L AS CD) AS CR) AS CU) <1 2 20 — — <1 <1 10 — — DATS OCT 1990 19... DBC 12... FBB 1991 06... APR 10... JUN 05... AUG 29... IRON, TOTAL RECOV- ERABLE (UO/L AS FB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UO/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UO/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTBY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 1300 140 50 <0.10 <0.10 <0.010 •cO.010 <1 0.04 0.04 356 RIO PORTOODBS BASIN 50116200 RIO PORTUOUBS AT PONCB, PR MATER-QUALITY RECORDS LOCATION.--Lat 18°00'20-, long 66°36'28», 1,300 ft (400 m) south of Las America* Avenue Bridge, 1.2 mi (1.9 km) •outh of CSC 50115900, 0.8 mi (1.3 km) west of Highway* 1 and 2 junction, and 0.7 mi (1.1 km) aoutheait of Ponce. DRAINAGE AREA.—18.9 mi2 (49.0 km2 ). PERIOD OF RECORD.--Water year* 1979 to current year. MATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 06... DEC 13... FBB 1991 19... APR 24... JUN 19... AUG 21... TIKE 0920 0810 1000 1040 0940 1140 DIS- CHARGE, INST. CUBIC FEET PER SECOND 61 8.9 1.7 0.48 7.1 21 SPE- CIFIC CON- DUCT- ANCE (US/CM) 384 583 600 564 400 257 PH (STAND- ARD UNITS) 8.5 7.7 7.9 8.0 7.9 7.9 TEMPER- ATURE HATER (DBG C) 24.5 22.0 25.0 28.0 25.0 25.5 TUR- BID- ITY (NTU) 20 4.2 3.5 2.0 6.6 41 OXYGEN, DIS- SOLVED (MQ/L) 9.1 6.3 5.0 7.0 5.4 6.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 108 71 60 88 64 83 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MO/L) 13 <10 21 50 17 23 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 6400 K1700 K630 2700 34000 60000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3200 280 K130 420 9400 21000 DATE NOV 1990 06... DEC 13... FBB 1991 19... APR 24... JUN 19... AUG 21... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MQ/L TOT FLD SOLVED AS MQ/L AS (MQ/L CACO3) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 150 0 47 8.7 18 140 0 40 10 54 96 0 30 5.1 15 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, NAT WH SULFATB RIDE, DIS- TOT FBT SULPTDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MQ/L AS (MG/L (MO/L (MG/L AS K) 0.6 1.4 2 2.4 0.7 1.8 CACO3 140 190 160 140 140 87 AS S) AS 804) AS CL) <0.5 23 <0.5 49 21 18 34 13 SOLIDS, RESIDUE DATE NOV 1990 06... DEC 13... FBB 1991 19... APR 24... JUN 19... AUG 21... FLUO- RIDB, DIS- SOLVED (MQ/L AS F) <0.10 — -- 0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 21 — — 20 — 17 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 221 — -- 293 -- 155 SOLIDS, DIS- SOLVED (TONS PER DAY) 36.4 — — 0.38 — 8.96 TOTAL AT 105 DBG. C, SUS- PENDED (MQ/L) 24 4 7 17 10 7 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.18 1.06 0.330 0.090 0.120 0.720 NITRO- GEN, NITRITE TOTAL (MQ/L AS N) 0.020 0.040 0.070 0.040 0.020 0.040 NITRO- GEN, . NO2+NO3 TOTAL (MG/L AS N) 1.20 1.10 0.400 0.130 0.140 0.760 NITRO- GEN, AMMONIA TOTAL (MQ/L AS N) 0.030 0.110 0.490 0.490 0.090 0.180 NITRO- GEN, ORGANIC TOTAL (MQ/L AS N) 0.37 0.29 0.71 1.5 0.51 0.52 non-ideal count RIO PORTUOOBS BASIN 50116200 RIO PORTUGUES AT PONCE, PR—Continued WATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 357 DATE HOV 1990 06... DEC 13... FBB 1991 19... APR 24... JUN 19... ADO 21... NITRO- GEN, AM- MONIA + NITRO- ORGANIC GEN, TOTAL TOTAL (MQ/L (MG/L AS N) 0.40 0.40 1.2 2.0 0.60 0.70 1.6 1.5 1.6 2.1 0.74 1.5 NITRO- PHOS- OBN, PHORU8 TOTAL TOTAL (MQ/L (MG/L AS N) AS NO3) AS P) 7.1 6.6 7.1 9.4 3.3 6.5 BARIUM, BORON, CADMIUM TOTAL TOTAL TOTAL ARSENIC RBCOV- RBCOV- RBCOV- TOTAL BRABLB ERABLE ERABLE (UQ/L (UQ/L (UO/L (UQ/L AS AS) AS BA) AS B) CHRO- MIUM, TOTAL RECOV- ERABLE (UG7L COPPER, TOTAL RBCOV- BRABLB (UG/L AS CD) AS CR) AS CU) 0.070 0.050 0.090 0.420 0.050 0.110 <1 <1 <100 <100 30 90 <1 <1 10 10 DATE NOV 1990 06... DEC 13... FBB 1991 19... APR 24... JUN 19... AUQ 21... IRON, TOTAL RECOV- ERABLE (UO/L AS FB) LEAD, TOTAL RECOV- ERABLE (UQ/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RBCOV- BRABLB (UQ/L AS HO) SELE- NIUM, TOTAL (UO/L AS SB) SILVER, TOTAL RECOV- ERABLE (UQ/L AS AO) ZINC, TOTAL RECOV- ERABLE (UO/L AS ZN) CYANIDE TOTAL (MO/L AS CN) PHENOLS TOTAL (UQ/L) MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MQ/L) 1200 670 60 340 <0.10 0.10 <1 <1 <1 <1 <0.010 10 <0.010 0.02 0.22 PESTICIDE ANALYSES DATE JUN 1991 19... PCB, TIME TOTAL (UG/L) 0940 ALDRIN, TOTAL (UQ/L) <0.010 CHLOR- DANB, TOTAL (UQ/L) DDD, TOTAL (UO/L) DDE, TOTAL (UQ/L) DOT, TOTAL (UO/L) DI- ELDRIN TOTAL (UG/L) BNDO- SULFAN, TOTAL (UG/L) BNDRIN, TOTAL (UG/L) HEPTA- CHLOR, TOTAL (UG/L) <0.010 <0.010 <0.010 <0.010 <0.010 <0.010 <0.010 HBPTA- CHLOR EPOXIDE LINDANB DATE TOTAL TOTAL (UG/L) (UG/L) JUN 1991 19... <0.010 <0.010 <0.01 NAPH- MBTH- OXY- CHLOR, TOTAL (UG/L) MIRBX, TOTAL (UQ/L) THA- LBNBS, POLY- CHLOR. TOTAL (UO/L) PER- THANB TOTAL (UQ/L) TOX- APHBNB, TOTAL (UO/L) <0.01 <0.10 <1 2,4-D, 2,4,5-T 2, 4-DP SILVBX, TOTAL TOTAL TOTAL TOTAL (UQ/L) (UQ/L) (UO/L) (UQ/L) <0.01 <0.01 <0.01 358 RIO OUAYANILIA BASIN 50124200 RIO OUAYANILIA NEAR OUAYANILLA, PR LOCATION.—Lat 18°02'40", long 66«47'53", Hydrologic Unit 21010004, on left bank, 0.7 mi (1.1 km) north of junction of Highway* 2 and 132, 0.6 mi (1.0 km) downstream from Quebrada Consejo, 1.8 mi (2.9 km) north-northwest from Plaza de Ouayanilla. DRAINAGE AREA.--18.9 mi* (49.0 km*). WATER-DISCHARGE RECORDS PERIOD OF RBCORD.—March 1981 to current year. GAQE.—Water-stage recorder. Elevation of gage is 80 Ct (24 m), from topographic map. RBHARKS.—Record* fair. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--10 years (1982-91), 27.3 ft'/s (0.773 •>/•), 17.17 in/yr (436 mm/yr), 17,316 acre-ft/yr (21.4 hmVyr)) median of yearly mean discharges, 24 ftVs (0.68 •>/•), 17,400 acre-ft/yr (21.0 hmVyr). EXTREMES FOR PERIOD OF RBCORD.--Maximum discharge, 14,700 ftVs (416 mVs), Sept. 12, 1982, gage height, 20.4 ft (6.218 m), from floodmarks, from rating curve extended above 100 ftVs (2.83 mVs) on basis of step-backwater analysis and indirect measurement of peak flow; minimum daily discharge, 0.97 ft}/s (0.027 mVs), Aug. 21, 1990. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 800 ft'/s (22.6 mVs) and maximum (*) i Date Oct. 9 Oct. 11 Oct. 14 Oct. 21 Time 1745 1445 1515 0120 Discharge (ftVs) (mVs) *2,697 1,726 1,500 90S 76.4 48.9 42.8 25.6 Gage height (ft) (m) •12.42 11.08 10.71 9.53 3.786 3.377 3.264 2.905 Date Oct. 24 Oct. 25 Oct. 27 Mar. 26 Time 1930 1930 1900 1615 Discharge (ftVs) (mVs) 1,550 1,770 864 922 43.9 50.1 24.5 26.1 Qage height (ft) (m) 10.79 11.15 9.43 9.57 3.289 3.398 2.874 2.917 Minimum daily discharge, 2.0 ftVs (0.057 mVs), May 26, 27. DISCHARGE, CUBIC FEET PBR SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 77 99 83 54 54 41 39 37 286 142 193 141 239 286 128 110 94 163 131 96 369 130 129 293 396 221 228 179 120 103 93 4754 153 396 37 9430 8.11 9.36 1990 1991 83 73 67 60 105 84 63 54 S3 51 48 46 42 39 36 42 39 36 30 52 42 33 33 36 41 43 36 30 25 26 —— 1448 48.3 105 25 2870 2.55 2.85 TOTAL 10191. TOTAL 9960 25 23 23 21 20 19 18 18 17 17 16 17 16 20 40 33 21 15 13 13 12 12 12 13 13 12 12 8.9 9.3 9.3 12 530.5 17.1 40 8.9 1050 .91 1.04 67 MEAN .1 MEAN 9.9 9.1 9.0 8.7 8.9 9.2 9.3 9.3 8.8 8.1 6.7 5. 5 7.1 4.7 4.0 4.6 5.0 5. 5 5.8 6.2 6.7 7.1 6.9 6.9 6.3 6.3 6.3 5.8 5.7 6.2 6.4 216.0 6.97 9.9 4.0 428 .37 .43 27.9 27.3 7.1 6.9 8.5 8.1 13 25 9.0 5.7 4.7 11 13 9.7 26 12 5.7 12 6.9 4.7 5.7 4.7 3.7 2.9 3.0 3.1 3.3 3.4 3.1 4.0 —— —— —— 225.9 8.07 26 2.9 448 .43 .44 MAX 396 MAX 396 4.5 3.9 3.6 4.5 6.5 5.9 4.1 3.7 3.7 3.4 3.6 3.4 3.6 3.3 3.1 2.9 3.0 3.1 3.1 2.9 3.9 7.3 7.3 4.6 4.0 99 37 12 7.8 5.9 5.1 269.7 8.70 99 2.9 535 .46 .53 MIN .97 MIN 2.0 6.0 5.6 12 5.9 14 57 34 10 6.0 4.6 5.3 5.3 4.7 4.7 4.2 4.2 3.7 3.3 3.3 2.9 2.9 2.9 3.3 2.9 2.2 2.2 2.2 2.2 2.5 2.5 222.5 7.42 57 2.2 441 .39 .44 AC-FT 20220 AC-FT 19760 2.2 23 17 5.8 7.8 30 72 83 71 43 75 98 87 49 29 21 16 19 18 13 11 9.2 8.3 7.1 8.1 7.6 7.4 5.6 5.3 5.0 3.9 858.3 27.7 98 2.2 1700 1.46 1.69 CFSM CFSM 3.3 3.3 3.1 3.3 3.3 2.8 2.6 2.4 2.5 2.5 2.5 2.9 2.9 2.5 7.0 2.8 2.2 2.5 2.9 2.9 2.9 5.9 2.8 2.5 2.5 2.0 2.0 5.3 2.8 9.6 —— 98.5 3.28 9.6 2.0 195 .17 .19 1.48 IN. 1.44 IN. 6.0 5.3 30 51 10 7.0 17 32 11 6.3 4.7 4.2 3.9 3.3 10 24 16 11 21 11 7.0 6.5 9.4 4.9 3.9 9.5 4.1 4.8 12 4.9 11 362.7 11.7 51 3.3 719 .62 .71 20.06 19.60 14 5.1 4.9 3.6 69 59 21 12 9.1 8.5 8.2 7.2 7.5 8.6 7.5 7.4 6.6 6.6 4.5 4.7 8.0 22 22 9.1 24 17 11 12 9.3 8.0 7.3 424.7 13.7 69 3.6 842 .72 .84 6.6 5.8 5. 5 5.1 5.6 9.3 17 9.5 7.6 6.3 6.1 7.0 14 6.3 42 26 107 38 18 20 24 28 17 12 7.6 11 18 20 30 19—— 549.3 18.3 107 5.1 1090 .97 1.08 RIO GUAYANHiLA BASIN 50124700 RIO GUAYANILLA AT CBNTRAL RUFINA, PR WATER-QUALITY RECORDS LOCATION.—Lat 18«00'40-, long 66«46'49", at dirt road bridge, 0.7 ai (1.1 km) fro* Mouth, 0 Central Rufina and 0.9 mi (1.4 km) southeast of Ouayanilla. DRAINAOB ARBA.--22.8 mij (59.1 In?). PERIOD OF RECORD.--Water yean 1960-65, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 369 9 mi (1.4 km) eait of DATE OCT 1990 16... DEC 05... PEB 1991 11... APR 29... JUN 10... AUO 09... TINE 0945 0915 0905 1045 0845 1150 DIS- CHARGE, INST. CUBIC FEET PER SECOND 29 17 9.4 9.3 1.1 4.0 SPE- CIFIC CON- DUCT- ANCE (US/CM) 430 525 469 819 800 578 PH (STAND- ARD UNITS) 8.0 7.7 7.8 7.4 7.5 8.0 TEMPER- ATURE WATER (DBG C) 25.0 22.5 24.0 30.0 27.5 30.5 TUR- BID- ITY (NTU) 10 1.4 7.6 1.6 1.6 4.0 OXYGEN, DIS- SOLVED (MG/L) 5.1 9.0 8.5 7.5 5.1 6.7 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 61 102 100 98 63 87 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 10 10 14 25 16 22 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 5400 230 K7000 K10 K10 10 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 2200 K30 K1SOO K10 K73 10 DATE OCT 1990 16... DEC 05... FEB 1991 11... APR 29... JUN 10... AUG 09... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CACO3) CAC03 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MO) AS MA) 190 0 51 15 14 270 0 77 20 68 200 0 53 16 32 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, WAT WH 8ULFATB RIDE, DIS- TOT FET SULFIDE DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 0.4 1.9 6.3 3.4 CAC03 160 190 170 213 230 190 AS 8) AS SO4) AS CL) <0.5 30 <0.5 93 54 15 77 35 DATE * OCT 1990 16... DEC 05... FBB 1991 11... APR 29... JUN 10... AUG 09... PLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.30 -- 0.20 SILICA, DIS- SOLVED (MG/L AS 8102) 21 — — 25 — 22 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 242 -- -- 494 -- 330 RESIDUE SOLIDS, TOTAL DIS- AT 105 SOLVED DBG. C, (TONS SUS- PBR PBNDBD DAY) (MG/L) 19.1 19 <1 4 12.5 3 9 3.57 <1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.69 1.28 1.28 1.86 3.16 0.400 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.020 0.020 0.140 0.340 0.260 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 1.70 1.30 1.30 2.00 3.50 0.660 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.050 0.130 0.100 0.140 2.00 2.50 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.25 0.27 0.80 0.56 1.0 0.70 K « non- ideal count 360 RIO GUAYANILLA BASIN 50124700 RIO GUAYANILLA AT CENTRAL ROFIHA, PR—Continued MATER-QUALITY DATA, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 16... DEC 05... FEE 1991 11... APR 29... JUN 10... ADQ 09... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) (00625) 0.30 0.40 0.90 0.70 3.0 3.2 NITRO- GEN, TOTAL (MG/L AS N) (00600) 2.0 1.7 2.2 2.7 6.5 3.9 NITRO- GEN, TOTAL (MG/L AS N03) (71887) 8.9 7.5 9.7 12 29 17 PHOS- PHORUS TOTAL (MG/L AS P) (00665) 0.120 0.180 0.370 1.00 2.10 1.40 ARSENIC TOTAL (UG/L AS AS) (01002) <1 — — 1 — — BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) (01007) <100 — — <100 — — BORON, TOTAL RECOV- ERABLE (UG/L AS B) (01022) <10 — — 150 — — CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) (01027) <1 — — <1 — — CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) (01034) 2 -- -- <1 — — COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) (01042) 40 — — 10 — — DATE OCT 1990 16... DEC 05... FEB 1991 11... APR 29... JUN 10... AUG 09... IRON, TOTAL RECOV- ERABLE (UG/L AS FB) (01045) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) (01051) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) (01055) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) (71900) SELE- NIUM, TOTAL (UG/L AS SB) (01147) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) (01077) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) (01092) CYANIDE TOTAL (MG/L AS CN) (00720) PHENOLS TOTAL (UG/L) (32730) METHY- LENE BLUE ACTIVE SUB- STANCE (MQ/L) (38260) 1000 140 15 40 110 •cO.10 0.20 <1 <1 <1 <1 <0.010 <0.010 <1 <1 0.03 0.16 PESTICIDE ANALYSES DATE JUN 1991 10... DATE JUN 1991 10... TIME 0845 BNDRIN, TOTAL (UG/L) PCB, TOTAL (UG/L) <0.1 BTHION, TOTAL (UG/L) ALDRIN, TOTAL (UG/L) •cO.010 HBPTA- CHLOR, TOTAL (UG/L) CHLOR- DANB, TOTAL (UG/L) <0.1 HEPTA- CHLOR EPOXIDB TOTAL (UG/L) ODD, TOTAL (UG/L) •cO.010 LINDANE TOTAL (UG/L) DDE, TOTAL (UG/L) •cO.010 MALA- THION, TOTAL (UG/L) DOT, TOTAL (UG/L) <0.010 MBTH- OXY- CHLOR, TOTAL (UG/L) DI- AZINON, TOTAL (UG/L) 0.06 METHYL PARA- THION, TOTAL (UG/L) DI- ELDRIN TOTAL (UG/L) •cO.010 METHYL TRI- THION, TOTAL (UG/L) BNDO- SULFAN, TOTAL (UO/L) •cO.010 MI REX, TOTAL (UG/L) •cO.010 <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 <0.01 <0.01 DATE JUN 1991 10... PARA- THION, TOTAL (UG/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) PER- THANE TOTAL (UG/L) TOX- APHENE, TOTAL (UG/L) TOTAL TRI- THION (UG/L) 2,4-D, TOTAL (UG/L) 2,4,5-T TOTAL (UG/L) 2, 4-DP TOTAL (UG/L) SILVEX, TOTAL (UG/L) <0.01 <0.10 <1 <0.01 <0.01 •cO.Ol <0.01 <0.01 361 RIO YAUCO BASIN 50125780 LAQO LUCCHBTTI AT DAMSITE, PR LOCATION.--Lat 18°05'37', long 66°51'54", Hydrologic Unit 21010004, at Antonio Lucchetti Dam on Rio Yauco, 3.9 mi (6.3 km) north of Yauco. DRAINAGE AREA. —17.4 mi» (45.1 km» ) . ELEVATION RECORDS PERIOD OF RECORD.--December 1989 to current year. GAGE.—Water-itage recorder. Datum of gage !• Mean sea level. REMARKS.—Lago Lucchettl was completed In 1952. The dam !• on Rio Yauco and is a unit of the Southwestern Puerto Rico Project. It provide! 16,500 acre-feet (20.3 hm5 ) of usable •torage for power generation and irrigation. The dam IB a concrete gravity structure with a total length of 591 ft (180 m), a maximum height of 178 ft (54 m), and a mmMimim width at the base of 150 ft (46 m). An ungated, overflow type spillway with a clear length of 171 ft (52 m) and a crest elevation of 570 ft (174 m) , occupies the central portion of the dam. The spillway was designed for a maximum capacity of 62,800 ft'/s (1,778 mI/s) at a design head of 20 ft (6 m). The dam is owned by Puerto Rico Electric Power Authority. Gage-height and precipitation setellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Mazimum elevation, 571.54 ft (174.21 m), Oct. 25; minimum elevation, 527.50 ft (160.78 m), Aug. 20, but may have been less during period of no gage-height record. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 571.54 ft (171.21 m), Oct. 25; minimum elevation, 527.50 ft (160.78 m), Aug. 20, but may have been less during period of no gage-height record. Capacity Table (based on data from Puerto Rico Water Resources Authority) Elevation, in feet Contents, in acre-feet Elevation, in feet Contents, in acre-feet 525 2,965 550 7,020 527 3,255 561 9,600 530 3,695 563 10,125 532 3,975 571 12,125 540 5,165 573 12,645 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY OBSERVATION AT 24iOO VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUO SEP 1 544.56 568.36 556.93 567.56 569.69 566.83 567.95 A 561.13 549.07 540.46 530.87 2 546.22 567.56 556.99 568.86 569.56 566.28 568.86 A 561.10 547.21 537.43 530.90 3 547.10 567.77 556.02 569.17 569.53 566.15 568.55 A 561.07 547.40 534.45 530.85 4 547.38 566.92 556.05 569.20 568.88 566.15 569.32 A 561.16 547.42 533.22 530.99 5 547.62 565.75 556.07 569.21 568.47 565.68 568.27 A 561.23 546.63 532.82 531.14 6 548.12 563.49 556.09 569.19 568.20 565.22 568.56 A 561.38 546.66 531.24 530.88 7 548.47 562.22 556.11 569.19 567.70 564.65 568.60 560.18 561.40 546.86 529.32 530.71 8 548.54 560.60 556.12 569.56 567.71 563.98 567.78 561.36 561.34 544.82 529.26 530.53 9 554.28 559.72 556.17 569.70 567.73 563.97 566.98 562.06 561.02 544.80 529.26 530.44 10 555.69 559.56 556.21 570.20 567.79 563.96 566.32 561.53 560.18 543.61 529.18 529.99 11 A 559.45 556.24 570.44 567.52 563.35 565.93 A 560.11 542.68 529.52 530.18 12 A 559.64 556.75 570.29 567.24 562.62 565.44 A 559.57 541.84 529.48 530.35 13 A 558.26 557.95 569.84 567.54 561.71 565.60 A 559.14 541.80 529.28 530.52 14 A 557.76 560.81 568.79 567.16 561.01 565.61 A 558.61 542.16 529.29 530.69 15 563.22 556.10 561.37 568.69 567.17 560.09 566.38 A 558.11 542.17 529.18 530.33 16 563.77 555.22 561.91 568.17 567.45 559.69 567.18 562.83 558.04 542.18 528.06 529.95 17 564.42 555.02 563.17 567.23 567.63 559.69 567.98 562.05 557.96 542.56 527.90 530.12 18 565.90 555.14 564.24 566.77 567.93 560.13 567.61 562.26 556.80 542.42 528.03 530.30 19 565.82 555.30 564.59 567.03 568.57 560.63 566.20 562.41 555.78 541.96 528.05 A 20 566.11 555.64 564.86 567.82 568.03 561.07 A 562.53 555.45 541.85 527.50 531.22 21 22 23 24 25 26 27 28 29 30 31 568.82 568.65 568.34 569.16 571.51 570.43 570.50 570.44 570.37 570.06 569.05 555.82 556.02 556.12 556.24 556.48 556.61 556.69 556.75 556.80 556.85 565.30 565.21 565.95 565.92 565.94 566.11 566.13 566.47 566.88 567.58 567.65 568.66 569.22 568.69 569.21 569.67 569.21 569.45 569.49 570.32 570.19 570.24 567.66 567.34 567.53 567.52 567.52 567.27 566.77 566.83 ___ 561.78 562.09 562.06 562.38 562.66 563.22 564.47 564.95 565.40 566.20 567.16 A 563.08 A A A A A A A A 562.81 562.81 562.12 A 562.08 562.06 562.06 562.40 562.37 561.51 561.05 554.45 554.43 554.37 553.27 552.92 551.27 551.02 549.62 549.21 549.15 541.90 543.21 543.96 544.32 544.30 543.36 542.86 544.29 544.68 543.74 543.20 527.92 528.10 528.36 529.48 530.72 530.82 531.75 531.90 531.98 531.40 531.10 532.02 532.70 532.87 533.02 533.14 533.14 533.32 533.33 532.98 533.08 MEAN —— 559.13 561.41 569.07 567.85 563.39 —— —— 557.01 544.06 530.53 MAX —— 568.36 567.65 570.44 569.69 567.16 —— —— 561.40 549.07 540.46 MIN —— 555.02 556.02 566.77 566.77 559.69 —— —— 549.15 541.80 527.50 A No gage-height record. 362 RIO LOCO BASIN 50129700 RIO LOCO AT OOANICA, PR WATER-QUALITY RECORDS LOCATION.--Lat 17»58'33", long 66°54'52 I> , 0.6 ml (1.0 ka) northwest of Guanica and 1.2 ml (1.9 km) northeaat of Bnsenada. DRAINAQB AREA.--Indeterminate. PRRIOD OF RECORD.--Water year* 1975 to current year. MATER-QUALITY DATA, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 18... DEC 07... FEE 1991 11... MAY 02... JUN 10... AUG 07... TIME 1245 1115 1010 1000 0950 0940 DIS- CHARGE, IMST. COBIC FEET PER SECOND E500 -- -- -- -- — . SPE- CIFIC CON- DUCT- ANCE (US/CM) 359 12000 26000 11600 26400 5170 PH (STAND- ARD UNITS) 7.4 7.5 7.5 7.5 7.2 7.5 TEMPER- ATURE HATER (DBG C) 26.5 25.0 28.5 31.0 31.0 28.0 TUR- BID- ITY (NTU) 15 10 8.0 5.0 2.4 23 OXYGEN, DIS- SOLVED (MQ/L) 4.2 3.6 3.6 2.8 2.6 1.6 OXYQBN, DIS- SOLVED (PER- CENT SATUR- ATION) 52 43 46 37 34 20 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MQ/L) 49 140 180 230 190 22 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2000 310 1700 280 K990 340 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 5100 610 670 260 450 290 DATE OCT 1990 18... DEC 07... FEB 1991 11... MAY 02... JUN 10... AUO 07... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MQ/L TOT FLD SOLVED AS CACO3) CACO3 MQ/L AS (MQ/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MQ/L (MG/L AS CA) AS MQ) AS NA) 140 0 30 15 19 1400 0 110 270 1900 160 1 37 16 41 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, NAT WH DIS- TOT PET SULFIDB SOLVED FIELD TOTAL (MQ/L MQ/L AS (MQ/L AS K) 0.7 5.1 22 74 1 3.1 CACO3 140 280 230 250 270 170 CHLO- SULFATE RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) 0.6 9.5 17 <0.5 620 3600 21 61 SOLIDS, RESIDUE DATE OCT 1990 18... DEC 07... FEB 1991 11... MAY 02... JUN 10... AUG 07... E - estimate K * non- ideal FLUO- RIDE, DIS- SOLVED (MG/L AS F) •cO.10 __ -- 0.70 -- 0.10 count SILICA, DIS- SOLVED (MQ/L AS 8102) 28 — — 25 — 21 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 208 -- -- 6750 -- 302 SOLIDS, DIS- SOLVED (TONS PER DAY) — — — — — — TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 37 15 17 20 13 10 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.160 0.570 0.280 — — 0.100 NITRO- GEN, NITRITE TOTAL (MG/L AS M) 0.040 0.030 0.020 •cO.010 •cO.010 0.010 NITRO- GEN, NO2+N03 TOTAL (MG/L AS M) 0.200 0.600 0.300 0.100 0.150 0.110 NITRO- GEN, AMMONIA TOTAL (MG/L AS M) 0.050 0.100 0.140 0.070 0.040 0.040 NITRO- GEN, ORGANIC TOTAL (MQ/L AS N) 1.2 0.10 0.46 0.53 0.36 0.66 RIO LOCO BASIN 50129700 RIO LOCO AT GUANICA, PR—Continued MATER-QUALITY DATA, WATER YBAR OCTOBBR 1990 TO SEPTEMBER 1991 363 DATE OCT 1990 18... DEC 07... FBB 1991 11... MAY 02... OUN 10... ADO 07... DATE OCT 1990 18... DEC 07... FBB 1991 11... MAY 02... OUN 10... ADO 07... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MQ/L AS N) 1.3 0.20 0.60 0.60 0.40 0.70 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MO/L AS N) 1.5 0.80 0.90 0.70 0.55 0.81 LEAD, TOTAL RECOV- ERABLE (UO/L AS PB) NITRO- GEN, TOTAL (MQ/L AS N03) 6.6 3.5 4.0 3.1 2.4 3.6 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS UN) PHOS- PHORUS TOTAL (MG/L AS P) 0.730 0.140 0.090 0.090 0.080 0.120 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 — — 1 — — SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — 200 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 30 — — 1000 — -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <2 — — CYANIDE TOTAL (MG/L AS CM) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 10 — — 9 — -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 30 — — 10 — -- MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 2300 1000 <2 410 200 <0.10 <0.10 <1 <2 <1 <1 <0.010 10 <0.010 <1 0.04 0.35 DATS JUN 1991 10... Til 0950 PCS, TOTAL (UG/L) ALDRIN, TOTAL PESTICIDE ANALYSES CHLOR- DANB, TOTAL (UG/L) (UG/L) <0.010 ODD, TOTAL (UG/L) DDB, TOTAL (UG/L) DOT, TOTAL (UG/L) <0.010 <0.010 <0.010 DI- AZINON, TOTAL (UG/L) DI- BNDO- BLDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 DATS OUN 1991 10... HEPTA- MBTH- METHYL HBPTA- CHLOR MALA- OXY- PARA- BNDRIN, BTHION, CHLOR, BPOXIDB LINDANB THION, CHLOR, THION, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) <0.010 <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 METHYL TRI- THION, MIRBX, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.01 DATS OUN 1991 10... PARA- THION, TOTAL (UG/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UO/L) PBR- THANB TOTAL (UG/L) TOX- APHENB, TOTAL (UG/L) TOTAL TRI- THION (UG/L) 2,4-D, TOTAL (UG/L) 2,4,5-T TOTAL (UG/L) 2, 4-DP TOTAL (UG/L) SILVEX, TOTAL (UG/L) <0.01 <0.10 <1 <0.01 <0.01 <0.01 <0.01 <0.01 364 THIS PAGE WAS LEFT BLANK INTENTIONALLY CARIBBEAN SEA 0123458 |_LTL_Jr_L^_J_ 01234 •A t.«» »••>» EXPLANATION L 138° SURFACE-WATER STATION AND NUMBER f 1297 QUALITY-OF-WATER STATION AND NUMBER » 143 WELL AND WELL NUMBER I Figure 24.--Rio Guanajibo basin. CO 0) 366 RIO OOANAJIBO BASIN 50131990 RIO OOANAJIBO AT HWY 119 AT SAN GERMAN, PR LOCATION.—Lat 18°05'06", long 67»02'02", Hydrologic Unit 21010003, on right bank, at bridge on Hwy 119, 0.6 ml (1.0 km) southwest of junction of Highways 119 and 2, 0.22 mi (0.35 km) northeast of junction of Highways 119 and 102, 0.74 mi (1.19 km) east from public Plaza of San German. DRAINAGE AREA.— 34.6 mi* (89.6 km*). MATER-DISCHARGE RECORDS PERIOD OF RECORD.—April to September 1991. GAGE.—Water-stage recorder. Elevation of gage is 148 ft (45.0 m) , from topographic map. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. EXTREMES FOR CURRENT PERIOD.—Peak discharges greater than base discharge of 300 ftj/s (8.50 •?/•) and maximum (*) i Discharge Gage height Discharge Gage height Date Time (ft'/s) (mj/s) (ft) (m) Date Time (ft'/s) (•?/•) (ft) (m) May 11 1930 375 10.6 6.41 1.954 Aug. 14 1915 *901 25.5 *7.40 2.256 Minimum daily discharge, 4.2 ft1/* (0.119 m'/m), June 27. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 18 6.4 5.7 8.4 14 2 31 6.4 5.3 8.2 13 3 22 5.9 24 7.5 12 4 20 5.6 29 7.1 11 5 28 5.3 11 7.2 9.6 6 62 5.2 8.4 e!3 11 7 94 5.1 12 8.1 13 8 67 5.1 30 6.3 12 9 97 4.6 13 5.9 10 10 60 4.4 9.1 5.9 9.1 11 81 5.2 7.5 6.1 8.6 12 85 5.8 6.6 6.0 8.5 13 49 5.3 6.3 29 10 14 33 4.6 6.1 129 8.8 15 25 4.7 7.2 47 7.8 16 20 5.6 30 22 21 17 e!2 17 5.2 37 21 27 18 12 21 4.9 25 30 18 19 11 32 4.5 22 17 14 20 12 27 4.5 15 14 14 21 12 20 4.6 13 13 17 22 11 15 4.9 12 20 22 23 11 13 5.1 17 23 16 24 9.6 12 4.4 13 22 13 25 10 14 4.4 10 55 11 26 10 12 4.5 8/5 41 10 27 10 10 4.2 8.0 27 9.8 28 10 9.2 4.6 13 22 13 29 10 8.1 4.5 23 19 12 30 12 7.7 4.8 12 16 10 31 —— 7.0 —— 8.8 15 TOTAL —— 1017.0 150.3 448.5 671.7 386.2 MEAN —— 32.8 5.01 14.5 21.7 12.9 MAX —— 97 6.4 37 129 27 MIN —— 7.0 4.2 5.3 5.9 7.8 AC-FT —— 2020 298 890 1330 766 CF8M —— .95 .14 .42 .63 .37 IN. —— 1.09 .16 .48 .72 .41 e Estimated RIO GUANAJIBO BASIN 50133600 RIO OUANAJIBO NEAR SAN GERMAN, PR WATER-QUALITY RECORDS LOCATION.—I*t 18°07'18-, long 67<>03'56-, at bridge on Highway 347, 2.2 mi (3.5 lot) northwest of San DRAINAGB ARBA.--45.5 mi3 (117.8 krf) . PERIOD OF RECORD.—Water year* 1979 to currant year. WATER QUALITY DATA, WATER YEARS OCTOBER 1990 TO SEPTEMBER 1991 367 German. DATE OCT 1990 16... DEC 07... FBB 1991 13... APR 30... JUN 11... AOQ 09... TINE 1200 1015 0940 1020 1025 0935 DIS- CHARGE, INST. CUBIC FEET PER SECOND 232 37 36 6.6 7.0 4.6 SPE- CIFIC CON- DUCT- ANCE (US/CM) 426 636 515 760 705 855 PH (STAND- ARD UNITS) 8.0 8.0 7.8 7.5 7.8 7.9 TEMPER- ATURE WATER (DBG C) 26.0 22.0 23.5 27.5 28.0 27.5 TUR- BID- ITY (NTU) 25 6.3 10 2.3 1.7 2.5 OXYGEN, DIS- SOLVED (MQ/L) 7.3 7.3 6.8 4.3 4.3 3.3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 89 82 79 54 55 42 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 56 <10 21 13 14 18 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3900 K10 22000 3500 K140 K1200 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3700 K60 600 340 K82 K36 DATE OCT 1990 16... DEC 07... FBB 1991 13... APR 30... JUN 11... AUG 09... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLO SOLVED AS MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L CACO3) CACO3 AS CA) AS MG) AS NA) SODIUM AD- SORP- TION (MG/L RATIO ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATB RIDE, DIS- TOT FBT SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L 210 0 22 37 11 0.3 1.4 270 0 30 48 51 1 3.5 260 1 29 45 72 2 3.1 120 250 220 246 240 260 <0.5 12 <0.5 64 100 (MG/L AS K) CAC03 AS 8) AS SO4) AS CL) 11 62 73 SOLIDS, RESIDUE DATE OCT 1990 16... DEC 07... FBB 1991 13... APR 30... JUN 11... AUG 09... FLUO- RIDE, DIS- SOLVED (MQ/L AS F) <0.10 -- -- 0.20 -- 0.20 SILICA, SUM OF SOLIDS, TOTAL DIS- CONSTI- DIS- AT 105 SOLVED TUENTS, (MG/L DIS- AS SOLVED 8102) (MG/L) 37 35 35 NITRO- NITRO- NITRO- NITRO- NITRO- GEN, GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC TOTAL TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L (MG/L (MG/L AS N) AS N) AS N) AS N) AS N) (TONS PER DAY) 203 127 441 7.81 513 6.30 SUS- PENDED (MG/L) 61 2 9 4 <1 <1 0.870 0.800 1.08 6.67 1.92 2.52 0.030 0.100 0.120 0.130 0.180 0.180 0.900 0.900 1.20 6.80 2.10 2.70 0.110 0.180 0.320 1.20 0.380 0.370 0.39 0.12 0.28 1.1 0.62 0.63 non-ideal count 368 RIO GUANAJIBO BASIN 50133600 RIO GUANAJIBO NEAR SAN GERMAN, PR--Continued NITER QUALITY DATA, MATER YEARS OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 16... DEC 07... FBB 1991 13... APR 30... JUN 11... AUG 09... DATE OCT 1990 16... DEC 07... FBB 1991 13... APR 30... JUN 11... AUG 09... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.30 0.60 2.3 1.0 1.0 IRON, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N) 1.4 1.2 1.8 9.1 3.1 3.7 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 6.2 5.3 8.0 40 14 16 MANGA- NESE, TOTAL RECOV- ERABLE (UO/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.180 0.260 0.450 3.10 1.10 1.10 MERCURY TOTAL RECOV- ERABLE (UQ/L AS HO) ARSENIC TOTAL (UG/L AS AS) <1 -- — <1 — — SELE- NIUM, TOTAL (UQ/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UQ/L AS BA) <100 — ~ <100 ~ — SILVER, TOTAL RECOV- ERABLE (UQ/L AS AQ) BORON, TOTAL RECOV- ERABLE (UQ/L AS B) 20 — — 220 — -- ZINC, TOTAL RECOV- ERABLE (UO/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UQ/L AS CD) <1 — — <1 ~ — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 46 — -- 1 -- -- PHENOLS TOTAL (UO/L) COPPER, TOTAL RECOV- ERABLE (UQ/L AS CU) 20 — — 20 — — MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 3600 190 12 130 80 <0.10 <0.10 <0.010 <0.010 0.03 0.07 369 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUERO8, PR LOCATION.--Lat 18°09'36", long «7°05'08", Hydrologic Unit 21010003 at bridge on Highway 348, 0.5 mi (0.8 km) southwest of RoMrio plaza. DRAINAGE AREA.—18.3 mi* (47.4 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1985 to currant year. GAGE.—Water-stage recorder. Elevation of gage im 50.0 ft (15.2 m), from topographic map. REMARKS.—Records fair. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--6 years (1986-91), 51.4 ftVs (1.456 m>/s), 38.14 in/yr (969 mm/yr), 37,240 acre-ft/yr (45.9 hmVyr). EXTREMES FOR PERIOD OF RECORD.—Maximum discharge, 7,480 ft'/s (212 mVs), Aug.24, 1988, gage height, 13.€4 ft (4.157 m) from rating curve extended above 900 ft'/s (25.5 mVs) on basis of step-backwater analysis/ minimum discharge €.5 ftVs (0.184 mVs), Apr. 30, 1991. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 1,500 ft'/s (42.5 mVs) and maximum (*)i Date Oct. 1 Oct. 17 Time 1415 1715 Discharge (ftVs) (mVs) 1,700 2,390 48.1 67.7 Gage height (ft) (m) 8.21 2.502 9.27 2.825 Date May Sept. 7 21 Time 1715 1630 Discharge (ft'/s) (m»/s) 1,870 *4,710 53.0 133 Gage height (ft) (m) 8.51 *11.77 2.594 3.587 Minimum discharge, 6.5 ft'/s (0.184 mVs), Apr. 30. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 368 209 129 95 82 74 67 79 62 67 88 73 214 198 178 233 377 210 200 146 207 135 103 96 211 207 130 112 102 88 80 4620 149 377 62 9160 8.14 9.39 1990 1991 72 66 63 60 114 75 61 57 54 51 48 47 45 44 42 42 41 39 39 38 38 36 35 34 68 42 31 28 28 27 —— 1465 48.8 114 27 2910 2.67 2.98 TOTAL 16102. TOTAL 14397. 26 25 25 25 26 26 25 24 24 24 23 24 25 26 27 23 22 22 21 21 21 21 21 21 20 20 20 21 20 19 19 707 22.8 27 19 1400 1.25 1.44 7 MEAN 5 MEAN 19 18 18 18 18 18 18 17 17 17 17 16 16 16 15 16 16 16 16 15 15 15 15 14 14 14 14 14 14 14 14 494 15.9 19 14 980 .87 1.00 44.1 MAX 39.4 MAX 16 14 15 26 33 20 16 15 15 21 24 19 25 18 15 13 12 12 19 14 13 13 11 11 11 10 9.6 9.5 —— 450.1 16.1 33 9.5 893 .88 .91 377 MIN 377 MIN 10 9.8 9.8 10 10 10 11 12 10 10 10 10 9.9 10 10 10 10 10 10 11 10 11 11 11 10 11 16 11 10 10 9.9 324.4 10.5 16 9.8 643 .57 .66 9.7 6.8 10 10 13 11 41 26 16 12 109.6 12 12 11 9.7 21 16 11 9.7 9.5 8.9 8.7 7.9 7.8 7.8 7.4 8.3 7.3 7.4 6.8 7.2 —— 356.0 11.9 41 6.8 706 .65 .72 AC-FT 31940 AC-FT 28560 25 21 14 21 17 45 200 139 99 72 62 57 45 46 37 29 23 66 114 100 51 36 29 25 23 24 52 45 31 24 22 1594 51.4 200 14 3160 2.81 3.24 CFSM 2.41 CFSM 2.16 22 19 17 16 15 15 14 13 13 12 12 12 12 11 12 11 11 13 14 49 34 23 16 13 14 18 13 14 16 64 —— 538 17.9 64 11 1070 .98 1.09 IN. IN. 35 19 40 34 22 18 36 32 20 17 16 15 14 18 64 53 80 151 80 46 36 85 83 42 34 30 27 31 29 34 133 1374 44.3 151 14 2730 2.42 2.79 32.73 29.27 58 38 32 32 32 30 26 26 24 22 22 20 23 22 25 20 19 18 17 16 17 18 21 17 22 45 33 25 21 19 18 778 25.1 58 16 1540 1.37 1.58 18 17 16 15 15 15 21 24 17 15 15 95 48 32 55 73 54 32 35 122 362 123 58 61 50 37 58 75 47 92 —— 1697 56.6 362 15 3370 3.09 3.45 370 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMTGUEROS, PR—Continued WATER-QUALITY RECORDS PERIOD OV RECORD.—HATER YEARS 1979 TO CURRENT YEAR. PERIOD Of DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGEi October 1985 to September 1986. INSTRUMENTATION.--US D-49 Sediment sampler since October 1985. Automatic sediment sampler since 1986 RBMARKS.—SediMmt samples were collected by a local observer once daily during low flow and more than once daily during high flow events for concentration and particle size analyses. Sediment samples are collected periodically by survey staff. Automatic sediment sampler set to collect samples above 200 cfs. daily mean, 1 mg/L EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONS! Um^iwum daily mean, 8,150 mg/L October 7, 1985; Mini] January 28, 1990. SEDIMENT LOADSt Maximum daily, 74,700 tons (67,800 tonnes) October 7, 1985; Minimum daily, 0.05 ton (0.04 Tonne) several days. EXTREMES FOR CURRENT YEAR.— SEDIMENT CONCENTRATIONS i Maximum daily mean, 1,440 mg/L June 7, 1990; Minimum daily mean, 1.0 mg/L January 28, 1990. SEDIMENT LOADSt Maximum daily, 3,920 tons (3,600 tonnes) September 24, 1990; Minimum daily 0.09 ton (0.08 tonne) few days. MATER-QUALITY DATA, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 18... DEC 06... FEB 1991 12... APR 30... JUN 11... AUO 08... TIME 1020 0910 0900 0845 0850 1245 DIS- CHARGE, IN8T. CUBIC FEET PER SECOND 204 56 17 6.1 12 25 SPE- CIFIC CON- DUCT- ANCE (US/CM) 624 283 263 303 283 264 PH (STAND- ARD UNITS) 8.0 8.2 8.3 7.9 8.1 8.1 TEMPER- ATURE WATER (DBG C) 23.0 20.5 22.5 24.5 24.5 27.0 TUR- BID- ITY (NTU) 25 1.5 4.4 4.3 2.5 3.4 OXYGEN, DIS- SOLVED (MG/L) 8.5 9.1 9.1 8.2 8.3 9.1 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 99 104 104 98 98 110 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 13 <10 <10 <10 <10 24 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) R6000 K11000 260 K80 K140 10 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K1600 2000 220 480 K120 80 DATE OCT 1990 18... DEC 06... FEB 1991 12... APR 30... JUN 11... AUG 08... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL NH WAT DI8- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L MAGNE- SIUM, SODIUM, DI8- DIS- SOLVED SOLVED (MG/L 96 140 120 (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) 17 13 5.3 27 17 11 25 15 8.2 SODIUM AD- SORP- TION RATIO ALKA- POTA8- LINITY SIUM, WAT WH DI8- TOT FBT SULFIDE SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L CHLO- SULPATB RIDE, DI8- DIS- SOLVED SOLVED AS K) 0.2 1.3 0.4 1.3 0.3 1.2 CACO3 94 130 120 136 130 72 (MG/L <0.5 6.9 <0.5 6.4 6.9 (MG/L AS S) AS 8O4) AS CL) 6.6 11 9.6 K - non-ideal count RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGDEROS, PR—Continued HATER QUALITY DATA, HATER YEARS OCTOBER 1990 TO SEPTEMBER 1991 371 DATE OCT 1990 18... DEC 06... PEB 1991 12... APR 30... OUN 11... AUG 08... DATE OCT 1990 18... DEC 06... PEB 1991 12... APR 30... OUN 11... AUG 08... DATE OCT 1990 18... DEC 06... PEB 1991 12... APR 30... OUN 11... AUG 08... FLUO- RIDB, DIS- SOLVED (HQ/L AS F) 0.30 -- -- 0.10 -- •cO.10 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (HG/L AS N) 0.60 <0.20 0.50 0.40 0.20 0.30 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 3200 -- -- 320 -- -- SILICA, DIS- SOLVED (MG/L AS SIO2) 29 — — 30 — 26 NITRO- GEN, TOTAL (MG/L AS N) 1.6 — 1.2 0.63 0.48 0.82 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 12 — — 4 — — SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (HG/L) 136 __ -- 185 -- 135 NITRO- GEN, TOTAL (MG/L AS NO3) 7.1 -- 5.3 2.8 2.1 3.6 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 80 __ -- 20 -_ -- SOLIDS, DIS- SOLVED (TONS PER DAY) 75 — — 3.05 — 9.01 PHOS- PHORUS TOTAL (MG/L AS P) 0.040 0.020 0.050 0.060 0.030 0.030 MERCURY TOTAL RECOV- ERABLE (UG/L AS HO) •cO.10 — — 0.20 — — RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 32 <1 6 12 <1 <1 ARSENIC TOTAL (UG/L AS AS) <1 __ -- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) <1 __ -- <1 __ -- NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.980 0.890 0.690 0.220 0.270 0.510 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 — — <100 — -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 — — <1 — — NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.010 0.010 0.010 0.010 0.010 BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 -- -- <10 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -- <10 -- -- NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.00 0.900 0.700 0.230 0.280 0.520 CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — -- CYANIDE TOTAL (MG/L AS CN) •cO.010 — — •cO.010 — — NITRO- GEN, AMMONIA TOTAL (HG/L AS N) 0.030 0.020 0.030 0.030 0.010 0.030 CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 18 -- -- 1 -- — — PHENOLS TOTAL (UG/L) 1 -- -- <1 -- -- NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.57 — 0.47 0.37 0.19 0.27 COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 20 — — 10 — — — MBTHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 0.02 — — 0.01 — — 372 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUBROS, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS 1979 TO CURRENT YEAR. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: OCTOBER 1990 TO SEPTEMBER 1991 INSTRUMENTATION.--US D-49 SEDIMENT SAMPLER SINCE OCTOBER 1985. AUTOMATIC SEDIMENT SAMPLER SINCE 1986 REMARKS.--sediment samples were collected by a local observer once dally during low flow and more than once daily during high flow events for concentration and particle size analyses. Sediment samples are collected periodically by survey staff. Automatic sediment sampler set to collect samples above 200 cfs. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONS t Maximum daily Man, 8,150 mg/L October 7, 1985} Minium daily mean, 1 mg/L January 28, 1990. SEDIMENT LOADS: Maximum daily, 74,700 tons (67,800 tonnes) October 7, 1985} Minimum daily, 0.05 ton (0.04 Tonne) several days. EXTREMES FOR CURRENT YEAR.-- SEDIMENT CONCENTRATIONSt Maximum daily mean, 1,150 mg/L October 1, 1990} Minimum daily mean, 2.0 mg/L several days. SEDIMENT LOADS: Maximum daily, 4,420 tons (4,000 tonnes) September 21, 1991} Minimum daily 0.8 ton (0.72 tonne) several days. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 18... DEC 06... FEB 1991 12... APR 30... JDN 11... AUG 08... TIME 1020 0910 0900 0845 0850 1245 DIS- CHARGE, INST. CUBIC FEET PER SECOND 204 56 17 6.1 12 25 SPE- CIFIC CON- DUCT- ANCE (US/CM) 624 283 263 303 283 264 PH (STAND- ARD UNITS) 8.0 8.2 8.3 7.9 8.1 8.1 TEMPER- ATURE WATER (DBG C) 23.0 20.5 22.5 24.5 24.5 27.0 TUR- BID- ITY (NTU) 25 1.5 4.4 4.3 2.5 3.4 OXYGEN, DIS- SOLVED (MG/L) 8.5 9.1 9.1 8.2 8.3 9.1 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 99 104 104 98 98 110 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 13 <10 <10 <10 <10 24 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) R6000 K11000 260 K80 K140 10 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K1600 2000 220 480 K120 80 DATE OCT 1990 18... DEC 06... FEB 1991 12... APR 30... JUN 11... AUG 08... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS CAC03) CACO3 96 140 120 MG/L AS (MG/L 17 27 25 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L AS CA) AS MO) AS NA) 13 5.3 17 11 SODIUM AD- SORP- TION (MG/L RATIO ALKA- POTAS- UNITY SIUM, WAT WH DIS- TOT PET SULFIDE SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 15 8.2 0.2 1.3 0.4 1.3 0.3 1.2 CACO3 94 130 120 136 130 72 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) <0.5 6.9 6.6 <0.5 6.4 11 6.9 9.6 K » non-ideal count RIO OUANAJIBO BASIN 50136400 RIO ROSARIO NEAR BORMIGUEROS, VS.—Continued WATER QUALITY DATA, WATER YEARS OCTOBER 1990 TO SEPTEMBER 1991 373 SOLIDS, RESIDUE FLOO- SILICA, SOU OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DATE OCT 1990 18... DEC 06... FEE 1991 12... APR 30... OUN 11... AUO 08... DATE OCT 1990 18... DEC 06... FBB 1991 12... APR 30... JUN 11... AUO 08... DATE OCT 1990 18... DEC 06... FBB 1991 12... APR 30... JUN 11... AUO 08... RIDE, DIS- SOLVED (MQ/L AS F) 0.30 — — 0.10 -- <0.10 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 <0.20 0.50 0.40 0.20 0.30 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 3200 — -- 320 — — DIS- SOLVED (MO/L AS SIO2) 29 — — 30 — 26 NITRO- GEN, TOTAL (HG/L AS N) 1.6 — 1.2 0.63 0.48 0.82 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 12 -- — 4 — — CONSTI- TUENTS, DIS- SOLVED (MO/L) 136 — — 185 -- 135 NITRO- GEN, TOTAL (MO/L AS NO3) 7.1 — 5.3 2.8 2.1 3.6 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 80 — — 20 — — DIS- SOLVED (TONS PER DAY) 75 — — 3.05 — 9.01 PHOS- PHORUS TOTAL (MO/L AS P) 0.040 0.020 0.050 0.060 0.030 0.030 MERCURY TOTAL RECOV- ERABLE (UG/L AS BO) <0.10 — — 0.20 — — AT 105 DBG. C, SUS- PENDED (MO/L) 32 <1 6 12 <1 <1 ARSENIC TOTAL (UG/L AS AS) <1 — — <1 — — - SELE- NIUM, TOTAL (UG/L AS SB) <1 — — <1 — — GEN, NITRATE TOTAL (MG/L AS N) 0.980 0.890 0.690 0.220 0.270 0.510 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 — — <100 — — SILVER, TOTAL RECOV- ERABLE ' (UG/L AS AG) <1 — — <1 — — GEN, NITRITE TOTAL (MO/L AS N) 0.020 0.010 0.010 0.010 0.010 0.010 BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 — — <10 — — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 — — <10 — — GEN, NO2+NO3 TOTAL (MG/L AS N) 1.00 0.900 0.700 0.230 0.280 0.520 CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — — — CYANIDE TOTAL (MO/L AS CN) <0.010 — — <0.010 — — GEN, AMMONIA TOTAL (MO/L AS N) - 0.030 0.020 0.030 0.030 0.010 0.030 CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 18 — — 1 -- — — PHENOLS TOTAL (UG/L) 1 — — <1 — — GEN, ORGANIC TOTAL (HG/L AS N) 0.57 — 0.47 0.37 0.19 0.27 COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) 20 — — 10 — — MBTHY- LBNB BLUB ACTIVE SUB- STANCE (HG/L) 0.02 — — 0.01 — — 374 RIO GOANAJIBO BASIN 50136400 RIO ROSARIO NBAR HORMIGUBRO8, PR—Continued SEDIMENT DI8CHAROB, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MO/L) (TONS/DAY) OCTOBER 20 209 129 95 82 74 67 79 62 67 88 73 214 198 178 233 377 210 200 146 207 135 103 96 211 207 130 112 102 88 80 1150 540 78 17 11 10 11 80 30 45 118 537 608 464 674 1140 369 229 34 341 21 13 20 574 258 21 15 13 14 14 3.0 475 30 4.4 2.4 2.1 2.0 23 5.3 11 46 5.8 597 704 272 894 3120 284 162 15 209 8.1 3.8 5.9 805 196 7.5 4.6 3.7 3.2 3.0 MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MO/L) (TONS/DAY) NOVEMBER 72 66 63 60 114 75 61 57 54 51 48 47 45 44 42 42 41 39 39 38 38 36 35 34 68 42 31 28 28 27 8 5 4 8 147 28 13 8 6 6 6 5 7 11 7 2 4 5 6 8 6 4 6 9 121 52 28 18 16 14 1.6 .88 .75 1.3 55 6.5 2.1 1.3 .86 .80 .85 .64 .89 1.3 .81 .28 .43 .58 .68 .84 .67 .44 .55 .82 52 6.3 2.4 1.4 1.1 .98 MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MO/L) (TONS/DAY) ngQOUDim 26 25 25 25 26 26 25 24 24 24 23 24 25 26 27 23 22 22 21 21 21 21 21 21 20 20 20 21 20 19 19 T"""""» 16 14 10 7 4 3 4 5 5 4 4 6 6 7 13 13 7 4 3 5 9 6 3 3 4 4 3 3 3 3 3 1.1 .91 .66 .48 .30 .21 .26 .32 .32 .28 .24 .41 .40 .48 1.2 .82 .46 .25 .18 .31 .49 .35 .16 .16 .20 .20 .16 .16 .15 .14 .15 TOTAL 4272 7907.8 1465 145.05 707 11.91 UUMMMM MMMMM MHHHH HHHHH H 10 O CO «4 00 Ot **UU1«j «JOtMMM MMMMM MMMMM MMUUU i i i I I I i i i "^ g! M HHHHH HHHHH KHHHH MH HH HHHHH HH * ta o o H o« H OHHHO (-• o o e o o o w o o OOMHO oo< 4 O i i i ui o« ill PH| CO•s 01 376 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGOBROS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SBPTBIfBBR 1991 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) APRIL 10 10 13 11 41 26 16 12 10 9.6 12 12 11 9.7 21 16 11 9.7 9.5 8.9 8.7 7.9 7.8 7.8 7.4 8.3 7.3 7.4 6.8 7.2 4 3 5 6 62 106 45 18 10 9 11 11 9 8 46 42 19 16 13 7 8 10 15 14 8 6 5 6 7 8 .11 .09 .15 .17 18 9.0 2.3 .58 .28 .25 .34 .34 .26 .21 4.8 2.0 .58 .40 .30 .18 .19 .19 .32 .30 .17 .14 .10 .12 .12 .18 MEAN DISCHARGE (CFS) 25 21 14 21 17 45 200 139 99 72 62 57 45 46 37 29 23 66 114 100 51 36 29 25 23 24 52 45 31 24 22 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MO/Ii) (TONS/DAY) MAY 26 13 23 26 13 88 701 248 111 71 141 84 85 80 26 16 15 184 313 135 58 25 11 8 6 5 57 62 33 14 10 6.6 1.0 1.1 1.6 .67 24 1520 147 38 29 27 14 12 10 2.9 1.3 .96 90 271 44 8.4 2.6 .85 .57 .38 .34 23 8.4 3.1 .94 .60 MEAN DISCHARGE (CFS) 22 19 17 16 15 15 14 13 13 12 12 12 12 11 12 11 11 13 14 49 34 23 16 13 14 18 13 14 16 64 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 9 10 9 8 11 11 7 5 5 10 17 13 5 5 6 6 5 6 6 105 89 81 65 40 28 73 30 17 22 110 .55 .50 .40 .35 .42 .44 .29 .18 .20 .32 .53 .40 .15 .17 .20 .19 .16 .23 .24 51 14 5.5 2.8 1.5 1.4 3.8 1.0 .63 1.0 57 TOTAL 356.0 42.17 1594 2291.31 538 145.55 377 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO HEAR HORMIGUBROS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MQ/L) (TONS/DAY) AUGUST MEAN MEAN CONCBN- SEDIMENT MEAN DISCHARGE TRATION DISCHARGE DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 35 19 40 34 22 18 36 32 20 17 16 15 14 18 64 53 80 151 80 46 36 85 83 42 34 30 27 31 29 34 133 1374 14049.5 JULY 79 43 89 91 40 39 49 83 43 23 16 12 13 17 108 112 466 641 89 25 20 170 105 28 17 14 11 20 20 29 570 —— 8.1 2.3 25 9.1 2.0 2.0 9.8 8.4 2.4 1.0 .67 .47 .48 1.3 44 19 306 821 23 3.3 1.9 138 33 3.3 1.5 1.1 .80 2.4 1.6 3.7 759 2235.62 18785.38 58 38 32 32 32 30 26 26 24 22 22 20 23 22 25 20 19 18 17 16 17 18 21 17 22 45 33 25 21 19 18 778 70 22 16 22 16 10 22 46 34 9 6 5 13 8 5 4 7 11 13 11 9 9 8 6 5 58 56 66 67 37 11 12 2.6 1.3 1.9 1.6 .86 1.5 3.2 2.3 .54 .35 .28 1.1 .53 .37 .24 .39 .50 .56 .47 .38 .46 .49 .28 .31 26 5.1 4.2 3.7 2.0 .51 MEAN DISCHARGE (CPS) 18 17 16 15 15 15 21 24 17 15 15 95 48 32 55 73 54 32 35 122 362 123 58 61 50 37 58 75 47 92 MEAN CONCEN- TRATION (MG/L) SEPTEMBER 10 10 9 6 8 12 23 14 12 11 13 426 80 47 99 91 70 18 25 430 1050 209 30 92 40 16 55 83 43 165 SEDIMENT DISCHARGE (TONS/ DAY) .45 .45 .38 .26 .34 .48 1.5 .90 .55 .44 .50 540 14 5.6 39 29 12 1.6 3.3 549 4420 89 5.4 27 6.9 1.6 15 22 6.5 106 76.02 1697 5899.15 378 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUBROS, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 PARTICLB-SIZB DISTRIBUTION OF SUSPENDED SEDIMENT DATE MAY 1991 19... •TON 30... JUL 17... 18... SEP 20... TIME 0648 1616 1900 1630 1624 DIS- CHARGE, INST. CUBIC FBBT PER SECOND SEDI- MENT, SUS- PENDED (MG/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 52 216 304 766 347 3250 4210 3200 3460 7850 456 2460 2630 7160 7360 28 26 30 10 18 43 36 40 17 30 62 54 56 34 54 DATE MAY 1991 19... JUN 30... JUL 17... 18... SEP 20... BSD. SUSP. FALL DIAM. PERCENT FINER THAN 016 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 73 66 68 50 54 83 80 80 70 70 99 94 97 84 85 99 96 99 94 94 100 98 100 98 98 100 98 100 99 99 100 100 100 100 100 379 RIO QUANAJIBO BASIN 50136400 RIO RO8ARIO HBAR BORMXOUBROS, PR—Continual WATER QUALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1990 17... 17... FEB 1991 04... APR 06... 15... JDN 20... JUL 18... 18... 18... 18... 31... SEP 21... TIME 1605 1654 1800 1750 1905 1753 1915 1600 1515 1755 1920 1608 STREAM- FLOW, INSTAN- TANEOUS (CFS) SEDI- MENT, SUS- PENDED (MG/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 1600 1695 24 17 51 225 285 685 573 447 250 2677 4840 7780 98 90 271 979 8890 4640 4870 4650 2240 5580 20900 35600 6.4 4.1 37 595 684 8580 7540 5610 1510 40300 68 78 88 98 98 90 75 89 83 96 97 65 380 RIO GOANAJIBO BASIN 50138000 RIO GDAMAJIBO NEAR HORMTOUBROS, PR LOCATION.--Lat 18°08'36", long 67°08'57", Hydrologie Unit 21010003, at bridge on Highway 100, 1.4 mi (2.3 km) west of Hormigueros, and 2.0 mi (3.2 km) downstream from Rio Rosario. DRAINAGE AREA.--120 mi* (311 km"). MATER-DISCHARGE RECORDS PERIOD OP RECORD.--Annual low-flow measurements 1959, monthly 1973 to current year. isurements April 1959 to November 1967, January GAGE.—miter-stage recorder. Datum of gage is at mean sea level. Previous to Nov. 7, 1980, at site 0.3 mi (0.5 km) upstream at datum 7.36 ft (2.243 m) higher. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--18 years (1974-91), 210 ftVs (5.947 mVs), 23.76 in/yr (604 mm/yr), 152,100 acre-ft/yr (188 hmVyr); median of yearly mean discharges, 194 ft1/" (5.49 mVs), 140,000 acre-ft/yr (172 hm?/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 128,000 ft3/" (3,620 mVs), Sept. 16, 1975, gage height, 28.50 ft (8.687 m), site and datum then in use, from rating curve extended above 100 ftVs (2.832 mVs) on basis of contracted-opening measurement of peak flow; minimum discharge, 4.6 ftVs (0.130 mVs), June 22, 1977. EXTREMES FOR CORRECT YEAR.--Peak discharges greater than base discharge of 2,000 ft1/" (56.6 •?/•) and maximum (*) i Date Oct. 13 Oct. 17 Oct. 18 Time 2000 0300 0400 Discharge (ft1/*) (•*/•) 2,330 2,640 4,450 66.0 74.8 126 Gage (ft) 19.81 20.04 21.36 height (m) 6 . 038 6.108 6.510 Date Oct. Oct. Oct. 19 21 26 Time 1700 1805 0800 Discharge (ft*/«) (»V«> 2,140 2,160 *4,720 60.6 61.2 134 Gage (ft) 19.62 19.64 •21.52 height (M) 5.980 5.986 6.559 Minimum daily discharge, 14 ftVs (0.396 mVs), April 24, 25, 30. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 622 681 461 294 250 276 227 293 264 428 661 897 1620 1350 1440 1120 2070 2650 1870 1020 1640 1080 618 498 869 3330 1190 659 516 425 359 29678 957 3330 227 58870 7.98 9.20 1990 1991 313 280 257 227 450 305 254 221 202 183 169 165 162 158 157 168 156 143 135 232 191 169 143 137 149 192 132 118 110 144 —— 5822 194 450 110 11550 1.62 1.80 TOTAL 62460 TOTAL 57301 141 117 118 107 102 98 94 92 90 87 85 83 85 86 147 150 103 95 89 84 80 76 73 71 70 67 75 74 86 82 73 2880 92.9 150 67 5710 .77 .89 MEAN MEAN 80 106 73 69 65 63 61 56 53 52 51 48 45 43 41 40 39 38 38 38 37 39 37 36 35 36 36 35 33 33 33 1489 48.0 106 33 2950 .40 .46 171 MAX 157 MAX 37 35 37 44 64 57 47 44 42 54 79 72 92 85 59 52 49 47 62 59 55 50 44 42 41 39 37 36 —— 1461 52.2 92 35 2900 .43 .45 3330 MIN 17 3330 MIN 14 37 35 32 31 33 30 30 37 29 26 26 26 23 23 20 19 19 18 20 19 18 22 28 18 16 69 79 •24 e!9 el8 e!7 861 27.8 79 16 1710 .23 .27 AC-FT AC-FT •16 •17 •20 22 32 108 67 41 31 26 30 29 28 28 29 44 28 24 21 19 19 17 15 14 14 17 15 15 15 14 --- 815 27.2 108 14 1620 .23 .25 123900 113700 20 55 39 41 44 273 480 572 415 312 250 317 214 198 135 112 98 109 161 230 181 131 109 95 87 79 79 106 80 69 62 5153 166 572 20 10220 1.39 1.60 CFSM 1.43 CFSM 1.31 60 57 53 48 45 41 38 35 33 32 28 28 24 22 22 23 23 39 35 118 127 98 64 54 49 55 46 52 52 74 —— 1475 49.2 127 22 2930 .41 .46 IN. 19.36 IN. 17.76 86 53 69 152 75 63 74 185 129 69 58 54 49 44 65 117 114 193 162 90 71 81 196 93 75 66 61 56 80 69 136 2885 93.1 196 44 5720 .78 .89 119 79 67 60 63 61 52 45 44 40 38 36 34 84 168 59 51 59 48 43 46 45 62 45 79 94 88 64 54 49 44 1920 61.9 168 34 3810 .52 .60 42 40 37 32 29 29 38 52 35 27 25 55 110 47 54 111 117 76 69 167 309 362 127 105 118 96 •138 •146 •111 158 —— 2862 95.4 362 25 5680 .79 .89 Estimated RIO GUANAJIBO BASIN 50138000 RIO GUANAJIBO NEAR KORMIGUEROS, PR--Continued MATER-QUALITY RECORDS PERIOD or RECORD.--Water yvars 1958 to current y«ar. HATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 381 DATE OCT 1990 22... DEC 07... FEB 1991 13... APR 30... JUN 11... AUG 08... TIME 1105 0820 0800 0700 0655 0950 DIS- CHARGE, INST. CUBIC FEET PER SECOND 11 99 77 14 30 49 SPE- CIFIC CON- DUCT- ANCE (US/CM) 288 494 433 510 475 388 PH (STAND- ARD UNITS) 7.5 7.9 8.0 7.8 7.9 7.9 TEMPER- ATURE HATER (DBG C) 24.5 22.5 23.5 25.5 25.5 26.5 TUR- BID- ITY (NTU) 33 7.5 12 3.3 3.0 28 OXYGEN, DIS- SOLVED (MG/L) 4.7 7.2 7.5 5.8 5.9 6.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 56 82 88 70 77 79 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 25 <10 10 19 <10 10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K930 K70 2800 240 440 140 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 2200 K82 490 790 420 240 DATE OCT 1990 22... DEC 07... FEB 1991 13... APR 30... JUN 11... AUQ 08... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CACO3) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MO) AS NA) 140 0 22 20 7.7 230 0 34 36 27 170 0 28 24 15 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATB RIDE, DIS- TOT FBT SULFIDE DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L AS K) 0.3 2.2 0.8 2.2 0.5 1.6 CACO3 130 220 180 210 210 170 (MG/L /s) at a reservoir elevation of 70.00 ft (21.34 m). Timber flashboards that were added to increase storage capacity were subsequently removed and their use discontinued. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation, 1462.43 ft (445.75 m). May 27, 1980; minimum elevation recorded, 1415.43 ft (431.42 m), June 2, 1990, but may have been less during period of no gage-height record June 2-5, 1990. EXTREMES OBSERVED FOR CURRENT YBAR.--Maximum elevation, 1460.94 ft (445.29 m), Oct. 26; minii 1419.47 ft (432.65 m), Apr.17. elevation recorded Capacity Table (based on data from Puerto Rico Water Resources Authority) Elevation, in feet 1415 1449 Contents, in acre-feet 3,960 10,660 Elevation, in feet Contents, in acre-feet 1460 1465 13,550 15,000 DAY 26 27 28 29 30 31 MEAN MAX MIN ELEVATION (FEET NGVD), WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY OBSERVATION AT 24100 VALUES OCT NOV DBG JAN FBB MAR APR MAY JUN JUL AUO SBP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 21 22 23 24 25 1448.82 1449.37 1449.22 1448.61 1447.68 1447.35 1448.32 1448.79 1451.00 1451.81 1451.83 1452.83 1454.49 1455.88 1456.69 1456.70 1456.69 1458.37 1459.45 1458.51 1459.22 1459.89 1459.90 1460.53 1460.76 1460.27 1460.27 1460.26 1460.26 1460.26 1460.26 1460.26 1460.26 1460.26 1460.26 1460.37 1460.37 1460.37 1460.20 1460.20 1460.19 1460.19 1460.18 1460.19 1460.47 1460.27 1460.26 1460.19 1460.18 1460.19 1460.15 1460.15 1460.15 1460.15 1460.12 1460.10 1460.17 1460.17 1460.17 1460.17 1460.17 1459.93 1460.35 1459.89 1459.89 1459.86 1438.08 A A 1434.76 1437.77 1443.42 1439.46 1438.15 A A 1434.67 1437.96 1443.96 1439.68 1438.41 A A 1434.61 1439.00 1444.32 1438.45 1438.53 A A 1434.24 1439.68 1444.69 1438.14 1438.57 A A 1433.48 1439.92 1445.05 1438.36 1438.79 1438.71 A 1432.77 1440.10 1445.38 1437.91 1438.65 1438.93 1423.87 1432.50 1441.03 1445.31 1438.41 1438.55 1439.06 1425.05 1432.40 1441.61 1444.44 1438.76 1438.64 1439.18 1426.30 1432.30 1441.93 1443.34 1438.09 1439.02 1439.33 1426.96 1431.98 1442.16 1442.87 1437.70 1438.89 1439.45 1428.51 1431.84 1442.42 1442.90 1437.53 1439.18 1439.53 1429.93 1433.65 1442.66 1441.94 1436.99 1439.10 1439.59 1430.84 1433.74 1442.87 1441.21 1436.89 1439.31 1439.57 1431.56 1433.75 1442.82 1440.58 1437.17 1439.48 1439.58 1432.07 1433.98 1442.15 1439.74 1436.66 1438.78 1439.34 1420.67 1431.71 1434.25 1442.26 1439.46 1437.17 1438.62 1439.37 1419.61 1432.13 1434.63 1443.21 1439.61 1437.59 1438.46 1438.51 1419.93 1432.61 1434.97 1444.16 1439.31 1438.10 1437.53 1437.36 1420.37 1433.15 1435.23 1444.21 1438.82 1437.26 1437.71 1436.33 1420.86 1433.47 1434.94 1444.55 1439.16 1437.96 1437.80 1434.71 1421.14 1433.47 1435.32 1444.56 1439.70 1437.63 1437.84 1434.25 1420.97 1433.82 1435.54 1443.12 1440.01 1438.30 1437.54 1434.32 1421.39 1434.16 1435.78 1442.08 1440.78 1437.80 1442.16 1437.63 1433.96 1421.78 1434.50 1436.04 1442.24 1441.29 1436.77 1440.89 1437.75 1433.26 1422.27 1434.86 1436.27 1442.49 1441.92 1435.98 1460.93 1460.72 1460.72 1460.60 1460.28 1460.27 1455.36 1460.93 1447.35 1460.16 1460.16 1460.16 1460.16 1460.15 1460.24 1460.47 1460.15 1440.75 1440.31 1440.31 1438.79 1438.24 1437.94 1437.89 1437.97 1437.98 —— 1432.56 1431.75 1430.57 1430.11 1429.07 1427.12 1422.74 1422.35 1422.84 1423.27 1423.72 —— 1435.20 1435.50 1434.56 1434.82 1434.94 1434.89 1436.52 1436.74 1436.99 1437.22 1437.44 1442.60 1442.61 1442.61 1441.92 1441.19 1440.72 1441.31 1440.77 1440.16 1439.74 1438.97 1438.91 1434.74 1434.78 1435.25 1435.42 1435.78 —— 1438.39 1439.48 1437.53 1434.62 1437.44 1431.84 1441.89 1444.56 1437.77 1441.58 1445.38 1438.82 1437.36 1439.68 1434.74 A No gage-height record. 387 RIO GRANDS DB ANA8CO BASIN 50143000 RIO ORANDB DB ANA8CO NEAR IARBS, PR WATER-QUALITY RECORDS LOCATION.—Lat 18«15'26-, lono 66«55'00-, at bridge on Highway 124, 0.7 mi (1.1 km) downstream from confluence of Rio Blanco and Rio Prieto, mud 3.7 mi (6.0 km) southwest of Lares plaza. DRAINAGE AREA. —26.3 mi3 (68.1 km3 ) this does not include 36.2 mi3 (93.8 km3 ) which contributes only dur- ing high floods, and 3.5 mi3 (9.1 km3 ) which contributes only part of its storm runoff. PERIOD OF RECORD.—Water years 1959-68, 1970 to current year. MATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE OCT 1990 30... DEC 27... PEB 1991 20... APR 18... JUN 11... AUQ 09... TIME 1330 0830 0845 1355 1345 1200 DIS- CHARGE, INST. CUBIC FBBT PER SECOND 461 47 38 22 38 55 SPE- CIFIC CON- DUCT- ANCE (US/CM) 218 278 270 276 264 301 PH (STAND- ARD UNITS) 8.3 8.1 8.0 8.4 8.5 8.2 TEMPER- ATURE WATER (DBG C) 25.5 19.5 21.0 26.5 29.5 26.5 TUR- BID- ITY (NTU) 14 3.0 4.0 4.0 1.7 4.5 OXYGEN, DIS- SOLVED (MG/L) 7.3 8.7 8.0 8.0 9.2 7.8 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 92 110 100 98 120 96 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 13 10 10 14 12 18 COLI- FORM, FECAL, 0.45 UM-MF (COLS. / 100 ML) 810 310 260 K91 K40 280 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 510 480 870 K73 K10 500 DATE OCT 1990 30... DEC 27... FEB 1991 20... APR 18... JTJN 11... AUG 09... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CACO3 85 0 23 120 0 31 110 0 31 MAGNE- SIUM, DIS- SOLVED (MG/L SODIUM, DIS- SOLVED (MG/L SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED (MG/L ALKA- LINITY WAT WH TOT FBI FIELD MG/L AI AS CA) AS MG) AS NA) 9.2 12 8.4 11 AS K) 6.7 9.0 0.4 2.0 0.5 1.5 0.5 1.5 CACO3 80 110 110 110 100 100 SULFATE 3ULFIDE DIS- TOTAL SOLVED (MG/L (MG/L <0.5 10 <0.5 17 17 CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS SO4) AS CL) 11 12 9.6 SOLIDS, DATE OCT 1990 30... DEC 27... FEE 1991 20... APR 18... JUN 11... AUG 09... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 — — 0.10 — <0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 25 — — 28 — 33 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 140 _ — 177 — 171 RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS BUS- TOTAL TOTAL TOTAL TOTAL TOTAL PER PBNDED (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 26 <1 <1 13 5 6 0.790 0.890 0.680 0.210 0.380 1.390 0.010 0.010 0.020 0.020 0.010 0.010 0.800 0.900 0.700 0.230 0.390 1.40 0.020 0.010 0.020 0.020 0.010 0.020 0.48 ~ 0.18 0.28 0.19 0.18 non-ideal count 388 RIO GRANDE IX ANASCO BASIN 50143000 RIO ORANDE DB ANASCO NEAR LARES, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATS OCT 1990 30... DEC 27... FBB 1991 20... APR 18... JUN 11... AUG 09... DATE OCT 1990 30... DBC 27... FBB 1991 20... APR 18... JUN 11... AUG 09... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 <0.20 0.20 0.30 0.20 0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.3 ~ 0.90 0.53 0.59 1.6 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 5.8 — 4.0 2.3 2.6 7.1 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.050 0.010 0.030 0.040 0.050 0.030 MERCURY TOTAL RECOV- ERABLE (UG/L AS HO) ARSENIC TOTAL (UG/L AS AS) <1 — — <1 — — SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — ~ <100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) •<10 — — •{10 — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 ~ — <1 ~ ~ CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 — — <1 — — PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 10 — — <10 — ~ MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1300 400 90 40 •cO.10 <0. 10 •cO.010 •cO.010 0.02 0.01 389 RIO GRANDS DB ANA8CO BASIN 50144000 RIO ORANDB DB AMA8CO NEAR SAN SEBASTIAN, PR LOCATION. ~ Lat 18«17' 85", long 67«03'05", Hydrologic Unit 21010003, on right bank, at downstream aide of bridge on Highway 108, 0.4 mi (0.6 km) downs t ream fro* Quebrada La Zumbadora, 4.4 mi (7.1 km) northweat of La* Marias, 5.4 ml (•.7 km) southwest of San Sebastian. DRAINAG« ARBA.— 94.3 mi* (244.2 km1 ), doea not include 36.2 ml 1 (93.8 km1 ) which contribute* only during high flood*, and 3.5 mi* (9.1 km*) which contribute* only part of ita storm runoff. WATER-DISCHARGE RECORDS PBRIOD OF RECORD. —March 1963 to current year. GAQE. — Water-stage recorder. Datum of gage is 103.72 ft (31.614 m) above mean sea level (Puerto Rico Department of Public Works bench mark). Previous to Oct. 30, 1975, at site 600 ft (180 m) upstream at same datum. REMARKS. — Records fair. Transbasin diversion (except during floods) to Rfo Yauco basin for hydroelectric power and irrigation above Lago Quayo, Yahuecas, and Prieto, combined useable storage 17,300 acre-ft (21.3 hm3 ) . Limited storm runoff is contributed to baain by 3. 5 mi* (9.1 km1 ) above Rfo Toro Diversion dam. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.-- 28 years (1964-91), 310 fta/s (8.779 m>/s), 44.64 in/yr (1,134 mm/yr), 224,600 acre-ft/yr (277 hmVyr); median of yearly mean discharges, 304 ftVs (8.61 m>/s), 220,000 acre-ft/yr (271 hmVyr) . EXTREMES FOR PBRIOD OF RECORD. — myimviB discharge, 140,000 ft3/* (3,960 m3/*), Sept. 16, 1975, gage height, 33.9 ft (10.333 m), from rating curve extended above 4,000 ft3/* (113 m3/*) on basis of slope-area measurement; minimum discharge, 31 ft3/* (0.878 m3/*), Apr. 19, 20, 1965. EXTREMES FOR CURRENT YEAR. --Peak discharges greater than base discharge of 6,000 ft3/* (170 m3/*) and maTJmiim (*) i Date Oct. 17 May 12 July 28 Time 1745 2200 1715 Discharge (ftVs) (mVs) 8,570 6,930 6,220 243 196 176 Gage height (ft) (m) 8.65 7.79 7.39 2.636 2.374 2.252 Date Aug. Aug. 5 21 Time 1700 1755 Discharge (ftVs) (m»/s) *13,800 6,150 391 174 Gage height (ft) (m) *10.93 3.331 7.35 2.240 Minimum discharge, 60 ftVs (1.699 m3/*), Apr. 22-25. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR 1210 1420 962 530 439 408 577 896 584 932 842 678 733 972 1520 1700 2490 1750 2230 1070 1390 1030 770 697 1230 1970 1500 1090 915 782 586 33903 1094 2490 408 67250 11.6 13.37 496 449 421 432 599 578 410 370 349 333 331 360 352 337 331 329 367 327 311 646 624 338 302 285 315 354 279 264 254 247 —— 11390 380 646 247 22590 4.03 4.49 1990 TOTAL 102607 1991 TOTAL 124840 246 238 242 240 231 226 220 215 213 213 210 207 232 491 229 217 199 188 184 178 178 176 173 169 167 161 160 155 152 152 149 6411 207 491 149 12720 2.19 2.53 MEAN 281 MEAN 342 156 149 144 144 139 138 133 129 131 128 126 125 127 123 121 116 114 113 108 107 107 107 108 107 103 101 101 99 96 95 92 3687 119 156 92 7310 1.26 1.45 MAX MAX 101 99 113 143 181 156 113 106 98 132 182 132 159 135 110 98 95 92 108 119 103 93 89 88 97 87 84 82 —— —— 3195 114 182 82 6340 1.21 1.26 2490 MIN 44 2690 MIN 58 84 81 77 76 74 76 76 81 79 73 74 83 78 74 71 69 67 68 69 72 68 74 84 75 67 129 294 117 82 75 71 2638 85.1 294 67 5230 .90 1.04 AC-FT AC-FT 68 126 177 228 253 172 108 83 77 72 74 87 77 71 70 136 84 81 79 66 63 59 58 58 95 161 76 72 76 69 —— 2976 99.2 253 58 5900 1.05 1.17 203500 247600 266 330 384 509 919 753 277 252 468 914 1650 2030 1170 661 362 293 413 396 474 1010 526 305 257 229 211 262 234 194 181 174 167 16271 525 2030 167 32270 5.57 6.42 CFSM 2.98 CFSM 3.63 169 159 150 144 141 137 133 124 132 128 115 112 110 113 212 149 157 744 258 182 192 185 175 131 116 161 164 401 615 1130 —— 6839 228 1130 110 13570 2.42 2.70 IN. 40 IN. 49 390 239 190 286 188 159 170 728 390 211 173 156 149 141 168 305 317 357 340 222 183 170 341 207 176 159 250 1210 351 228 975 9529 307 1210 141 18900 3.26 3.76 .48 .25 1010 455 574 339 405 267 746 241 2690 225 1010 217 464 701 368 480 313 283 279 247 257 310 249 466 250 518 354 282 382 254 368 418 283 334 235 274 211 260 480 605 867 1020 382 579 404 319 282 269 729 321 469 243 525 887 366 439 294 310 258 260 674 16178 11823 522 394 2690 1020 211 217 32090 23450 5.53 4.18 6.38 4.66 390 RIO GRANDS DB ANA8CO BASIN 50144000 RIO GRANTS DB ANASCO HEAR SAN SEBASTIAN, PR—Continued (National stream-quality accounting network station) WATER-QUALITY RECORDS PERIOD OF RECORD.—Water years 1963 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DI8- OXYGBN, COLI- DATE OCT 1990 04... JAN 1991 10... APR 18... JUL 23... TIME 1230 1055 1015 1245 CHARGE, IN8T. CUBIC FEET PER SECOND 519 130 79 305 SPE- CIFIC CON- DUCT- ANCE (US/CM) 208 230 250 196 PH (STAND- ARD UNITS) 7.4 8.5 8.0 7.8 TEMPER- ATURE WATER (DBG C) 25.5 23.5 25.0 26.0 TUR- BID- ITY (NTU) 17 1.4 3.0 71 OXYGEN, DIS- SOLVED (MG/L) 7.8 9.2 8.4 7.7 DIS- SOLVED (PER- CENT SATUR- ATION) 95 107 100 93 FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 20000 220 2200 K7100 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 8600 K10 250 2300 HARD- NESS TOTAL (MG/L AS CACO3) 86 110 110 82 DATE OCT 1990 04... JAN 1991 10... APR 18... JUL 23... CALCIUM DIS- SOLVED (MG/L AS CA) 22 28 28 21 MAGNE- SIUM, DIS- SOLVED (MQ/L AS MO) 7.6 9.4 8.9 7.2 SODIUM, DIS- SOLVED (MG/L AS NA) 8.1 10 10 6.9 SODIUM AD- SORP- TION RATIO 0.4 0.4 0.4 0.3 POTAS- SIUM, DIS- SOLVED (MQ/L AS K) 1.5 1.4 1.7 1.4 ALKA- LINITY WAT WE TOT PET FIELD MG/L AS CACO3 85 108 98 76 SULFATB DIS- SOLVED (MG/L AS 804) 9.9 13 11 8.4 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 7.8 11 9.8 7.4 FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 <0.10 0.20 0.30 SILICA, DIS- SOLVED (MG/L AS 8IO2) 27 27 28 23 SOLIDS, RESIDUE AT 180 DBG. C DIS- SOLVED (MG/L) 137 160 178 103 DATE OCT 1990 04... JAN 1991 10... APR 18... JUL 23... SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 139 169 159 126 SOLIDS, DIS- SOLVED (TONS PER DAY) 194 59 38.2 84.8 NITRO- GEN, NO2+N03 DIS- SOLVED (MG/L AS N) 1.10 0.500 0.490 0.900 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS N) 0.020 0.020 0.020 0.040 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.03 0.03 0.03 0.05 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.40 0.50 0.20 0.50 PHOS- PHORUS TOTAL (MG/L AS P) 0.060 0.030 O.OCO 0.110 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.030 0.040 0.040 0.040 PHOS- PHORUS ORTHO, DIS- SOLVED (MG/L AS P) 0.030 <0.010 0.020 0.030 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS PO4) 0.09 — 0.06 0.09 K - non-ideal count RIO GRANDB DB ANASCO BASIN 50144000 RIO GRANDB DB ANASCO NEAR SAN SEBASTIAN, PR—CONTINUBD (NATIONAL STREAM-QUALITY ACCOUNTING NETWORK STATION) WATER-QUALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 391 DATS OCT 1990 04... JAN 1991 10... APR 18... JUL 23... ALUM- INUM, DIS- SOLVED (UG/L AS AL) ARSENIC DIS- SOLVED (UG/L AS AS) BARIUM, DIS- SOLVED (UG/L AS BA) BERYL- LIUM, DIS- SOLVED (UG/L AS BE) CADMIUM DIS- SOLVED (UG/L AS CD) CHRO- MIUM, DIS- SOLVED (UG/L AS CR) COBALT, DIS- SOLVED (UG/L AS CO) COPPER, DIS- SOLVED (UG/L AS CU) IRON, DIS- SOLVED (UG/L AS FB) LEAD, DIS- SOLVED (UG/L AS PB) 80 30 40 110 32 30 32 33 58 51 47 45 44 42 42 44 88 61 50 45 40 50 41 38 36 --_ ___ --- 1419 50.7 88 36 2810 .71 .74 3630 MIN 24 5060 MIN 27 37 35 34 33 32 32 31 33 33 30 31 32 31 30 30 29 28 29 29 28 29 31 35 30 29 30 47 35- 29 28 28 978 31.5 47 28 1940 .44 .51 AC-FT AC-FT 27 28 256 333 161 62 48 43 41 39 39 39 37 36 35 38 40 71 62 61 42 39 39 39 65 142 64 90 84 57 --- 2157 71.9 333 27 4280 1.01 1.13 123500 190900 51 77 187 332 133 139 75 65 298 259 115 167 127 197 438 831 5060 677 377 2070 1190 484 236 189 167 181 150 127 117 111 105 14732 475 5060 51 29220 6.67 7.70 CFSM 2.40 CFSM 3.70 103 102 101 91 89 95 87 83 164 197 106 90 81 76 99 196 154 109 e300 e400 e!80 el32 e!30 e!25 elOS e84 e98 ellS e230 e400 4322 144 400 76 8570 2.02 2.26 IN. 32 IN. 50 e660 eSOO e210 elSS e!80 e!70 e!25 e!23 e300 e450 e200 e!40 e!20 el!3 e!06 e!20 e!80 e232 e250 e255 e!90 e!45 e!30 e200 e250 e!35 e!24 elSO e600 e450 e200 7163 231 660 106 14210 3.25 3.74 .54 .29 eSOO e720 e740 e350 e400 elSOO elOOO e450 e300 e250 e215 e!95 e!88 e!85 247 3110 912 e270 e207 898 760 948 459 269 269 378 1410 2110 378 501 1070 21189 684 3110 185 42030 9.60 11.07 847 389 268 225 204 190 757 2240 e224 e!81 e!63 e278 e337 e2W) elSO e!60 e270 e210 el70 e!60 e390 e620 e!90 162 1190 467 2550 1300 333 237 15102 503 2550 160 29950 7.07 7.89 Estimate 399 RIO CULBBRINAS BASIN 50149100 RIO CULBBRINAS NEAR AGUADA, PR WATER-QUALITY RECORDS LOCATION.—Lat 18»24'03*, long 67»09'40*, at bridg* on Highway 3, and 2.3 mi (3.7 km) northeast of Aguada plaza. ORAIHAOB AREA.--97.0 «i2 (251.2 la?) . PERIOD OV RECORD.—Hater year* 1958, 1970 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE NOV 1990 06... JAN 1991 11... FBB 21... APR 17... JUN 12... AUG 08... TIME 1145 0745 1030 1140 1115 1230 DIS- CHARGE, INST. CUBIC FEET PER SECOND 590 74 81 44 111 234 SPE- CIFIC CON- DUCT- ANCE (OS/CM) 330 303 326 331 342 352 PH (STAND- ARD UNITS) 7.9 8.0 7.9 7.5 7.8 7.7 TEMPER- ATURE HATER (DBG C) 25.0 24.0 24.0 27.0 27.5 28.0 TUR- BID- ITY (NTU) 6.5 94 1.6 15 17 17 OXYGEN, DIS- SOLVED (MG/L) 7.6 7.0 7.0 4.7 4.3 4.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 30 80 81 58 53 61 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 30 <10 10 20 24 18 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K10000 390 2400 K1200 600 K200 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 4900 K163 310 540 800 K1600 DATE NOV 1990 06... JAN 1991 11... FBB 21... APR 17... JON 12... AUG 08... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH NAT DIS- (MG/L TOT FLO SOLVED AS MG/L AS (MG/L CACO3) CACO3 150 0 53 130 0 43 130 0 44 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MQ) AS NA) 5.3 9.4 6.1 16 5.7 11 SODIUM AD- SORP- TION RATIO ALKA- POTAS- UNITY CHLO- SIUM, NAT WH SULFATE RIDE, DIS- TOT FET SULFIDE DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 0.3 2.7 0.6 3.2 0.4 2.4 CACO3 140 130 120 130 130 130 AS 8) AS 804) AS CL) <0.5 14 12 <0.5 11 19 9.0 12 SOLIDS, DATE NOV 1990 06... JAN 1991 11... FBB 21... APR 17... JUN 12... AUG 08... PLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- <0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 21 — — 36 — 29 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 207 -- -- 212 -- 191 RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 (TONS SUS- TOTAL TOTAL TOTAL PER PBNDBD (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) 145 4 12 12 15 68 0.780 0.390 0.970 0.620 0.780 0.930 0.020 0.010 0.130 0.020 0.030 0.020 0.800 0.400 1.10 0.640 0.810 0.950 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.120 0.030 0.080 0.110 0.080 0.070 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.98 0.47 0.32 0.39 0.62 0.53 non-ideal count 400 RIO CULBBRINAS BASIN 50149100 RIO CULBBRINAS NEAR AGUADA, PR--Continued MATER-QUALITY DATA, MATER YEAR OCTOBER 1990 TO SBPTBMBBR 1991 DATE NOV 1990 06... JAN 1991 11... PEB 21... APR 17... JUN 12... AUQ 08... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MQ/L AS N) 1.1 0.50 0.40 0.50 0.70 0.60 NITRO- GEN, TOTAL (MQ/L AS N) 1.9 0.90 1.5 1.1 1.5 1.6 NITRO- GEN, TOTAL (MG/L AS N03) 8.4 4.0 6.6 5.0 6.7 6.9 PHOS- PHORUS TOTAL (MG/L AS P) 0.120 0.020 0.130 0.170 0.130 0.070 ARSENIC TOTAL (UQ/L AS AS) <1 __ __ <1 __ — BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — — BORON, CADMIUM TOTAL TOTAL RBCOV- RECOV- ERABLE SUABLE (UQ/L (UG/L AS B) AS CD) <10 9 __ __ <10 7 __ — CHRO- MIUM, COPPER, TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLE (UQ/L (UG/L AS CR) AS CU) 5 40 __ __ 1 40 __ — DATE NOV 1990 06... JAN 1991 11... PBB 21... APR 17... JUN 12... AUG 08... IRON, TOTAL RECOV- ERABLE (UQ/L AS PB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UQ/L AS MN) MERCURY TOTAL RECOV- ERABLE (UQ/L AS HO) SELE- NIUM, TOTAL (UQ/L AS SB) SILVER, TOTAL RECOV- ERABLE (UQ/L AS AQ) ZINC, TOTAL RECOV- ERABLE (UQ/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LENB BLUB ACTIVE SUB- STANCE (MQ/L) 4200 690 39 190 70 0.10 <0.10 <1 <1 <1 <1 100 <0.010 60 <0.010 <1 0.01 0.03 DATE JDN 1991 12... PCB, TIMB TOTAL (UQ/L) 1115 ALDRIN, TOTAL PESTICIDE ANALYSES CHLOR- DANB, TOTAL (UQ/L) (UQ/L) <0.010 ODD, TOTAL (UG/L) DDE, TOTAL (UG/L) DDT, TOTAL (UQ/L) DI- AZINON, TOTAL (UG/L) <0.010 <0.010 <0.010 DI- ENDO- ELDRIN SDLFAN, TOTAL TOTAL (00/L) (UG/L) 0.02 <0.010 <0.010 HBPTA- MBTH- METHYL METHYL HEPTA- CHLOR MALA- OXY- PARA- TRI- BNDRIN, BTHION, CHLOR, EPOXIDE LINDANB THION, CHLOR, THION, THION, MIRBX, DATE TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UQ/L) (UG/L) (00/L) (UG/L) (UQ/L) (UG/L) (UQ/L) (0Q/L) (UQ/L) (UG/L) JUN 1991 12... <0.010 <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 <0.01 <0.01 DATE JUN 1991 12... PARA- THION, TOTAL (UQ/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UQ/L) PER- THAKB TOTAL (UG/L) TOX- APHENB, TOTAL (UG/L) TOTAL TRI- THION (UQ/L) 2,4-D, TOTAL (UG/L) 2,4,5-T TOTAL (UQ/L) 2, 4 -DP TOTAL (UQ/L) SILVEX, TOTAL (UQ/D <0.01 <0.10 <1 <0.01 0.19 <0.01 <0.01 <0.01 401 Discharge Partial-Record Stations in Puerto Rico 402 DISCHARGE AT PARTIAL-RECORD STATIONS As the number of streams on which streamflow information is likely to be desired far exceeds the number of stream-gaging stations feasible to operate at one time, the Geological Survey collects limited streamflow data at sites other than stream-gaging stations. When limited streamflow data are collected on a systematic basis over a period of years for use in hydrologic analyses, the site at which the data are collected is called a partial-record station. Data collected at these partial-record stations are useable in low-flow or floodflow analyses, depending on the type of data collected. In addition, discharge measurements are made at other sites not included in the partial- record program. These measurements are generally made in times of drought or flood to give better areal coverage to those events. Those measurements and others collected for some special reason are called measurements at miscellane- ous sites. Low-flow partial-record stations Measurements of streamflow in the areas covered by this report made at low-flow partial-record stations are given in the following table. These measurements were made during periods of base flow when streamflow is pri- marily from ground-water storage. These measurements, when correlated with the simultaneous discharge of nearby stream when continuous records are available, will give a picture of the low-flow potentiality of stream. STATION NUMBER Discharge STATION NAME isurements made at low-flow partial-records stations during water year 1991 PUBLICATION RECORD 50095900 Quebrada Melania near Jobos, PR 50097000 Quebrada Cimarrona near Jobos, PR 50097800 Rio Seco near Central Quamani, PR 50100200 Rio Lapa near Rabo del Buey, PR 50100300 Rio Jajome at Jajome, PR 50100450 Rio Hajada at La Plena, PR 50100700 Rio Majada at Rabo del Buey, PR LOCATION AND BASIN Rio Melania basin Lat 17°57'51", long 66°59'30' Hydrologic unit 21010004. 0.6 mi (1.0 km) upstream from bridge on Hwy 3. Lat 17°59'18", long 66°10'59". Hydrologic unit 21010004. Barrio Poxo Hondo, 2.4 mi (3.7 km) north from Puerto de Jobos, and 4.0 mi (6.4 km) northwest from Guayama Plaza. Rio Seco basin Lat 17<>58'06•, long 66°10'52". Hydrologic unit 21010004. At Bridge on Hwy 3, .2 mi (0.3 (0.3 km) north of Central Guamani, and 1.2 mi (1.9 km) northwest of Jobos. Rio Salinas (Nigua) basin Lat 18°03'36", long 66°14'28". Hydrologic unit 21010004. Barrio Lapa, at Hwy 1, 1.6 mi (2.6 km) upstream from conflu- ence with Rio Majada, and 6.2 mi (10 km) southwest from Cayey Plaxa. Lat 18°03'49 B , long 66°09'38". Hydrologic unit 21010004. Barrio Jijome Bajo, at Hwy 708, 3.5 mi (5.6 km) south from Cayey Plaza. Lat 18°02'40", long 66°12'27 B . Hydrologic unit 21010004. Barrio Quebrada Yegua, at Hwy 712, 2.0 mi (3.2 km) northeast from Albergue Olimpico, and 5.5 mi (8.8 km) southwest fron Cayey Plasa. Lat 18°02'17", long 66°14'27". Hydrologic unit 21010004. Barrio Lapa, 0.2 mi (0.3 km) upstream from confluence with Rio Lapa, 400 ft upstream from intersection of Hwy's 1 and 712, and 0.2 mi (0.3 km) nortwest from Albergue Olimpico. DRAINAGE AREA mi* (km1 ) 2.75 (7.13) 3.09 (8.00) 11.2 (29.0) 10.0 (25.8) 4.56 (11.8) 16.7 (43.2) 22.2 (57.5) DATE 3/06/91 4/16/91 3/06/91 4/16/91 3/06/91 4/16/91 3/06/91 4/16/91 3/06/91 4/16/91 3/06/91 4/16/91 3/06/91 4/16/91 TIME 1025 1215 1110 1050 1055 1200 1400 0730 0750 0950 0900 0900 1205 0810 STREAM- FLOW ft*/s (mVs) 0.38 (0.011) 0.24 (0.007) 0.12 (0.003) 0.00 0.00 0.00 3.28 (0.093) 1.65 (0.047) 2.67 (0.076) 1.18 (0.033) 6.62 (0.19) 2.76 (0.078) 5.40 (0.15) 0.98 (0.028) DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations—Continued 403 STATION NUMBER STATION NAME 50102000 Rio Salinas at Salinas, PR 50102400 Rio Jueyes at Rio Jueyes, PR 50103000 Rio Jueyes near Jauea, PR 50104000 Rio Coamo near Paste, PR 50105400 Rio Cuyon at La Guava, PR 50105600 Rio Cuy6n near Comma, PR 50105900 Quebrada Monterii near Coamo, PR 50106100 Rio Commo at Comma, PR 50106600 Rio de La Ulna near CoajK>, PR 50106650 Rio del Paste Coamo, PR LOCATION AND BASIN Lat 17»58'42- / long 66«18'17-. Hydrologic unit 21010004. At Bridge on Hwy I/ and 0.4 Hi (0.6 km) west from Salinas Plaza. Rio Jueyes basin Lat 18*01'17", long 66°19'51". Hydrologic unit 21010004. Barrio Rio Jueyes, at Hwy 154, 1.3 mi (2.1 km) upstream from Hwy 52, and 4.5 mi (7.2 km) Southeast from Coamo Plaza. Lat 17<>58'45-, long 66°20'20-. Hydrologic unit 21010004. At bridge on Hwy 1, 1.8 mi (2.9 km) east of Jaueas, and 2.7 mi (4.3 km) west of Salinas Plaza. Rio Coamo basin Lat 18<>07'08", long 66°21'52 I> . Hydrologic unit 21010004. Barrio Paste, at Hwy 555, 2.6 mi (4.2 km) northwest from Coamo Plaza. Lat 18<>05'20", long 66oi6'17". Hydrologic unit 21010004. Barrio Algarrobo, at Hwy 717, 1.0 mi (1.6 km) southwest from Cerro Verdtin, and 5.6 mi (9.0 km) east from Coamo Plaza. Lat 18»05'25-, long 66°18'SO-. Hydrologic unit 21010004. Barrio Cuy6n, at Hwy 14, 0.8 mi (1.3 km) southeast from Cerro Santa Ana, and 2.8 mi (4.5 km) northeast from Coamo Plaza. Lat 18005'13", long 66*21'04-. Hydrologic unit 21010004. Barrio Paste, at confluence with Rio Cuy6n, and 0.5 mi (0.8 km) northeast from Coamo Plaza. Lat 18005'00", long 66»21'16-. Hydrologic unit 21010004. Coamo, at Hwy 14, 500 ft (152 m) downstream from con- fluence with Rio Cuy6n, and 0.2 mi (0.3 km) east from Coamo Plaza. Lat 18005'04", long 66<>23'22-. Hydrologic Unit 21010004. Barrio Santa Catalina, at Hwy 150, 2.2 mi (3.5 km) west from Coamo Plaza. Lat 18004'49", long 66°22'32-. Hydrologic unit 21010004. Barrio San Idelfonso, at Hwy 150, 1.3 mi (2.1 km) west from Coamo Plaza. DRAINAGE AREA (km«) 52.4 (136) 3.50 (9.06) 8.56 (22.2) 9.05 (23.4) 4.33 (11.2) 18.1 (46.8) 2.62 (6.78) 1.80 (4.67) DATE 3/06/91 4/16/91 3/07/91 4/16/91 3/07/91 4/16/91 3/08/91 4/18/91 3/08/91 4/18/91 TIME 1305 1305 1040 1410 1120 1345 0850 0825 0820 0750 STREAM FLOWS ftVs (mVs) 2.96 (0.084) 1.71 (0.048) 0.97 (0.027) 0.69 (0.020) 0.00 0.00 3/08/91 4/17/91 3/06/91 4/16/91 3/07/91 4/17/91 0715 1350 1450 0640 0650 0705 3.98 (0.113) 3.71 (0.105) 1.20 (0.034) 0.76 (0.022) 2.94 (0.083) 1.42 (0.040) 7.12 (18.4) 43.5 :ii3) 3/07/91 4/17/91 3/07/91 4/17/91 0835 0835 0750 0750 0.58 (0.016) 0.37 (0.010) 9.43 (0.267) 4.69 (0.133) 0.30 (0.008) 0.15 (0.004) 0.27 (0.008) 0.13 (0.004) 404 DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations—Continued STATION NUMBER 50106700 50106820 50107000 50107800 50108200 50108500 50109000 50109500 STATION NAME Rio de La Mina at Coano, PR Rio Coano at Bafios de Coano, PR Rio Coano near Santa Isabel, PR Rio Dascalabrado near Sanja Blanca, PR Rio Descalabrado at Las Ollas, PR Rio Descalabrado near Santa IBabel, PR Rio Cafias near Juana Dial, PR Rio Cafias near Santa Isabel, PR 50110550 50110700 Rio Jacaguas at Villalba, PR Rio To* Vaca at Pedro Garcia, PR LOCATION DRAINAGE STREAM AREA 'LOWS AND ni» DATE TIME ft'/s (kn») («Vs) BASIN Lat 18«03'56", long 66°22'29". 5.88 3/07/91 1510 0.54 Hydrologic unit 21010004. (15.2) (0.015) Barrio San Idelfonso, at Hwy 14, 0.2 ni (0.3 kn) upstrean 4/17/91 1255 0.33 fron confluence with Rio Coano, (0.009) and 1.7 ni (2.7 kn) fron Coano Plaza. Lat 18«02'23», long 66«22'31». 58.5 3/07/91 0935 12.1 Hydrologic unit 21010004. (152) (0.343) Barrio San Idelfonso, at the end of Hwy 546, 3.3 ni (5.3 kn) 4/17/91 0935 7.52 southwest fron Coano Plaza. (0.213) Lat 17«58'36", long 66°25'10". 69.3 3/07/91 1150 0.54 Hydrologic unit 21010004. At (179) (0.015) bridge on Hwy 1 at Velaxquex, 1.1 ni (1.8 kn) northwest of 4/17/91 1030 0.00 Santa Isabel Plaza. Rio Descalabrado basin Lat 18«05'24", long 66°24'30". 4.27 3/08/91 0920 0.46 Hydrologic unit 21010004. (11.0) (0.013) Barrio Santa Catalina, at Hwy 150, 2.0 ni (3.2 kn) southeast 4/18/91 0910 0.25 fron Lago Toa Vaca, and 3.4 ni (0.007) (5.5 kn) northwest fron Coano Plaza. Lat 18«02'10", long 66°25'36". 13.9 Hydrologic unit 21010004. (36.0) Barrio Descalabrado, at Hwy 536, 0.6 ni (1.0 kn) upstrean fron Hwy 52, and 2.2 ni (3.5 kn) northwest fron Cerro del Muerto. Lat 17<>58'45", long 66°26'35". 18.1 Hydrologic unit 21010004. At (46.9) bridge on Hwy 1, 0.9 ni (1.4 kn) upstrean fron nouth, and 3.1 ni (5.0 kn) northwest of Santa Isabel. Rio Cafias basin Lat 18«02'41", long 66«27'26". 2.88 3/07/91 1350 0.10 Hydrologic unit 21010004. (7.47) (0.003) Barrio Rio Cafias Arriba, at Hwy 14, 3.3 east fron Juana 4/17/91 1145 0.11 Diaz Plata. (0.003) Lat 17«59'39", long 66«28'33". 6.38 3/07/91 1315 0.00 Hydrologic unit 21010004. At (16.5) bridge on Hwy 1, 0.5 ni (0.8 kn) fron nouth, 0.6 ni (1.0 4/17/91 1120 0.00 kn) east of Pastillo, and 5.1 ni (8.2 kn) northwest of Santa Isabel Plaza. Rio Jacaguas basin Lat 18«07'37", long 66°29'42". 12.2 3/14/91 0955 44.5 Hydrologic unit 21010004. (31.7) (1.260) Barrio Hato Puerco Arriba, upstrean fron Water Treatment 4/25/91 0910 41.1 Plant, 100 ft (30 n) downstrean (1.164) fron confluence with Quebrada Achiote, 0.2 ni (0.3 kn) south- west fron Villalba. Lat 18«08'11", long 66°23'47". 3.09 3/14/91 1245 0.28 Hydrologic unit 21010004. (8.00) (0.008) Barrio Pedro Garcia, 2.1 ni (3.4 kn) southeast fron inter- 4/25/91 1140 0.05 section of Hwy's 143 and 155, (0.001) and 4.1 ni (6.6 kn) northeast Lago Toa Vaca. 3/07/91 4/17/91 3/07/91 4/17/91 1420 1215 1235 1050 1.56 (2.044) 0.25 (0.007) 0.89 (0.025) 0.41 (0.012) DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations—Continued 405 STATION NUMBER 50110900 50111720 50112400 50112700 STATION NAME Rio Toa Vaca upstream from Lago Toa Vaca, PR Quebrada Guanabana near Juana D£ax, PR Rio Inab6n at Real An6n, PR Rio Quayo near Collores, PR 50112750 Quebrada Indalecia at Collores, PR 50112800 Rio Quayo upstreai from Diversion at Collores, PR 50113790 50113800 50114150 Rio San Patrieio upstream from Lago Cerrillos, PR Rio Cerrillos upstream from Lago Cerrillos, PR Quebrada Ausubo near Ponce, PR LOCATION AND BASIN Lat 18<>07'36", long 66«27'25*. Hydrologie unit 21010004. Barrio Caonillas Arriba, at Hwy 553, 0.5 mi (0.8 km) upstream Lago Toa Vaea, and 2.4 mi (3.9 km) east from Villalba. Lat 18<>03'12", long 66°29'02". Hydrologie unit 21010004. Barrio Tijeras, at Hwy 14, 1.5 mi (2.4 km) east from Juana Diai Plxa. Rio Inab6n basin Lat 18°07'22*, long 66«34'20". Rydrologie unit 21010004. Barrio Anon, at Hwy 511, 1.0 mi (1.6 km) northeast from Cerro Santo Domingo, and 4.5 mi (7.2 km) northwest from Lago Ouayabal. Lat 18«07'24", long 66«33'27". Rydrologie unit 21010004. Barrio Collores, at Hwy 5.17 about 400 ft (122 m) west from escuela Quaraguao 0.9 mi (1.4 km) northwest from inter- section of Hwy's 517 and 5.12, and 3.5 mi (5.6 km) northwest from Lago Toa Vaea. Lat 18°06'33*, long 66°32'20*. Hydrologie unit 21010004. Barrio Collores, 200 ft (61 m) upstream from conflu- ence with Rio Quayo, 0.9 mi (1.4 km) northeast from Cerro Agustinillo, and 2.2 mi (3.5 km) northwest from Lago Quayabal. Lat 180Q5'10", long 66<>32'24*. Hydrologie unit 21010004. Barrio Collores, 2.1 mi (3.4 km) southwest from Lago Quayabal, and 3.1 mi (5.0 km) northwest from Juana Diai Plaxa. Rio Bucani basin Lat 18«07'12', long 66«36'27". Hydrologie unit 21010004. Barrio Maraguez, 1.5 mi (2.4 km) north- west from Cerro Santo Domingo, 3.6 mi (5.8 km) northwest from Lago Cerrillos, and 7.3 mi from (12 km) Degetau Plaxa, Ponee. Lat 18°07'01", long 66°36'17*. Hydrologie unit 21010004. At barrio Karagoei, 1.3 mi (2.1 km) west from Cerro Santo Domingo, 3.3 mi (5.3 km) northwest from Lago Cerrillos, and 7.2 mi (12 km) from Degetau Plaxa, Ponce. Lat 18«03'09", long 66«35'08". Hydrologie unit 21010004. At Barrio Machuelo Arriba, 2.4 mi (3.9 km) west from Goto Laurel, 1.5 mi (2.4 km) south from Lago Cerrillos, and 3.8 mi (6.1 km) northeast from Degetau Plaxa, Ponce. DRAINAGE AREA mi' (km') 14.2 (36.8) 1.72 (4.46) 6.00 (15.4) 1.67 (4.34) 3.52 (9.11) 9.55 (24.7) 5.84 (15.1) 11.9 (30.7) 1.18 (3.05) DATE 3/14/91 4/25/91 3/13/91 4/22/01 3/13/91 4/23/91 3/13/91 4/23/91 3/13/91 4/23/91 3/13/91 4/23/91 3/12/91 4/22/91 3/12/91 4/22/91 3/11/91 4/22/91 TIME 1105 1010 0820 1205 1205 1200 1015 1040 1110 1115 0905 0950 1310 1415 1435 1503 1045 1245 STREAM FLOWS ftj/s (mVs) 2.42 (0.068) 1.93 (0.055) 0.09 (0.002) 0.01 (0.000) 2.39 (0.068) 3.96 (0.112) 0.92 (0.026) 0.91 (0.026) 0.00 0.00 1.56 (0.044) 1.90 (0.054) 2.97 (0.084) 2.83 (0.080) 5.24 (0.148) 6.01 (0.170) 0.00 0.00 406 DISCHARGE AT PARTIAL-RECORD STATIONS low-flow partial-record stations—Continued STATION NUMBER STATION NAME 50114200 Rio Bayagan Ponce, PR 50114600 Rio Bucani at Ponc« PR 50114900 Rio Portugufs near Tibes, PR 50115400 Rio Portuguts near Ponce, PR 50115450 Rio Chiquito at Portuguts, PR 50115600 Rio Chiquito near Ponce, PR 50116500 Rio Portugufs at Bwy 2 By-Pass at Ponce, PR 50116800 Rio Caftas at Magueyes PR 50116970 Rio Caftas downstream from Las Americas Ave., PR LOCATION AND BASIN L»t 18<>02'51-, long 66«35'12". Bydrologic unit 21010004. At Barrio Machuelo Arriba, 2.5 mi (4.0 Km) west of Goto Laurel, 1.9 mi (3.0 km) south from Lago Cerrillos, and 3.0 mi (4.8 km) northeast from Degetau Plaza, Ponce. L»t 18<>00'28-, long 66°35'36*. Bydrologic unit 21010004. At bridge on Bwy 1, 0.2 mi (0.3 km) east of intersection of Bwys 1 and 2, 1.5 mi (2.4 km) east of Degetau Plaza in Ponce, 3.1 mi (5.0 km) upstream from mouth. Rio Portuguts basin Lat 180 04'26", long 66°38'35*. Bydrologic unit 21010004. At barrio Tibes, 0.5 mi (0.8 km) southwest from Cerro del Diablo, 6.0 mi (9.6 km) northeast from Peftuelas, and 6.2 mi (10 km) north from Ponce. Lat 18°02'27', long 66036'41". Bydrologic unit 21010004. At barrio Portugues, 1.0 mi (1.6 km) west from Jardines de Ponce, 0.4 mi (0.6 km) north from confluence with Rio Chi- quito, and 1.9 mi (3.0 km) north from Degetau Plaxa, Ponce. Lat 18*04'11", long 66°37'00*. Bydrologic unit 21010004. At barrio Portugufs, 2.1 mi (3.4 km) northwest from Jardines de Ponce, 1.7 mi (2.7 km) southwest from Pico Pinto, and 2.8 mi (4.5 km) north from Degetau Plaxa, Ponce. Lat 180 02'37-, long 66°36'31'. Bydrologic unit 21010004. At barrio Portugufs, 0.6 mi (1.0 km) west from Jardines de Ponce, 0.8 mi (1.3 km) South from Cerro El Oato, and 2.1 mi (3.4 km) north from Degetau Plaza, Ponce. Lat 17»59'52", long 66°36'52". Bydrologic unit 21010004. At bridge on Bwy 2 By-Pass, 1.1 mi (1.8 km) south of Degetau Plaza, and 2.0 mi (3.2 km) upstream from mouth. Rio Matilde basin Lat 18°04'26-, long 66°39'07-. Bydrologic unit 21010004. At barrio llagueyes, 2.4 mi (3.9 km) southwest from Cerro del Diablo, 4.7 mi (7.6 km) northwest from Pefiuelas, and (6.4 km) northwest from Ponce. Lat 18°QQ'3T, long 66°38'26'. Bydrologic unit 21010004. 0.5 mi (0.8 km) upstream from con- fluence with Rio Pastille. DRAINAGE AREA mi* (km*) 3.82 (9.88) 27.3 (70.7) DATE 3/11/91 4/22/91 3/11/91 4/23/91 TIKE 1030 1240 1230 1615 7.27 (18.8) 12.2 (31.6) 3.12 (8.09) 4.43 (11.5) 20.5 (53.1) 4.00 (10.3) 8.50 (22.0) 3/12/91 4/24/91 3/12/91 4/24/91 3/12/91 4/24/91 3/12/91 4/24/91 3/11/91 4/23/91 3/11/91 4/24/91 3/11/91 4/24/91 0810 1035 0915 1125 1040 1210 1010 1230 1330 1535 1445 0825 1540 0910 STREAM FLOWS ft*/s (mVs) 0.00 0.00 2.24 (0.063) 2.94 (0.083) 3.66 (0.104) 2.51 (0.071) 3.65 (0.103) 1.69 (0.048) 0.60 (0.017) 0.20 (0.006) 0.19 (0.005) 0.52 (0.015) 0.70 (0.020) 0.74 (0.021) 1.89 (0.054) 2.05 (0.058) 6.82 (0.193) 4.33 (0.123) DI8CHAROB AT PARTIAL-RECORD STATIONS Low-flow partial-record stations—Continued 407 STATION NUMBER 50117800 STATION NAME Rio Pastille at Pastille, PR 50118300 Rio Pastille near Pone*, PR 50119000 Rio Matilda at Pone*, PR 50119200 Quebrada del Agua at Playa da Ponc«, PR 50120550 Rio Tallaboa near Quebrada Ceiba, PR 50120700 Rio Ouayan** near Pefiuelas, PR 50121000 Rio Tallaboa at Pefiuelas, PR 50122000 Rio Tallaboa at Tallaboa, PR 50122500 Rio Vacant near Pefiuelas, PR 50122900 Rio Macani at Magi Arriba, PR LOCATION AND BASIN Lat 18«02'53", long 66«39'52". Hydrologie unit 21010004. Barrio Quebrada Lim6n at Hwy 502, 0.8 Hi (1.3 km) northwest of Hwy's 502 and 132 inter- section, 0.9 mi (1.4 km ) west of lUgueyes and 3.1 Hi (5.0 km) northwest from Ponce. Lat 18«00'31", long 66«38'39". Hydrologie unit 21010004. Canas Orbano, on bridge, 0.7 mi (1.1 km) downstream fro* Jardines del Caribe and 1.1 mi (1.7 km) west of Bscuela Dr. Pila, Ponce. Lat 17«59'53", long 66°38'06". Hydrologie unit 21010004. At Hwy 2, 1.1 Hi (1.8 km) upstream from mouth. Lat 17«59'13", long 66°38'22 <> . Hydrologie unit 21010004. 700 ft (213 m) upstream fro* con- fluence with Rio Matilda. Rio Tallaboa basin Lat 18«04'18", long 66«42'03". Hydrologie unit 21010004. Barrio Quebrada Ceiba, on bridge, 0.06 mi (0.1 km) west from Hwy 391, 1.2 mi (2.0 km) north from Tallaboa Alta and 1.7 mi (2.7 km) northeast from Pefiuelas Plaza. Lat 18<>04'03", long 66°43'36". Hydrologie unit 21010004. Barrio Jaguas, on Hwy 386, 0.2 mi (0.4 km) northeast from Hwy's 386 and 132 intersection, 0.6 mi (1.0 km) northeast from Pefiuelas Plaza. Lat 18°03'02", long 66«43'19". Hydrologie unit 21010004. 350 ft (106.7 m) downstream from Hwy 132 bridge, 0.6 mi (1.0 km) south of Pefiuelas. Lat 18«00'31", long 66«43'49". Hydrologie unit 21010004. At bridge at Hacienda Dolores, 700 ft (213 H) upstream from Hwy 127, 0.8 mi (1.3 km) north- west of Tallaboa, and 7.6 mi (12.2 km) west of Degetau Plaza, Ponce. Rio Macani basin Lat 18«03'40", long 66°46'12-. Hydrologie unit 21010004. Barrio Macana at Hwy's 131 and 132 intersection, 5.5 mi (8.8 km) northeast from Yauco, and 2.8 (4.5 km) northeast from Ouayanilla Plaza. Lat 18«01'00", long 66«45'57". Hydrologie unit 21010004. 1.8 mi (2.8 km) east of Ouayanilla Plaza, 200 ft (60 H) upstream from bridge on Hwy 2, and 0.6 mi (1.0 km) upstream from mouth. DRAINAGE AREA Hi* (km*) 4.32 (11.2) 10.6 (27.6) 20.5 (53.2) 6.45 (16.7) 8.41 (21.8) 7.29 (18.9) 24.2 (62.7) 31.6 (81.7) DATE 3/11/91 4/22/91 3/11/91 4/22/91 TIME 0910 0930 0850 0910 3/11/91 4/22/91 3/11/91 4/22/91 0805 0825 1430 1500 3/11/91 4/22/91 3/11/91 4/22/91 3/11/91 4/22/91 3/11/91 4/22/91 1010 1020 1120 1125 1210 1220 1315 1400 2.77 (7.17) 8.98 (23.2) 3/13/91 4/24/91 3/13/91 4/24/91 0910 0935 0750 0750 STREAM FLOWS fts/« (mV«) 0.84 (0.024) 0.47 (0.013) 0.00 0.00 4.43 (0.125) 3.87 (0.110) 0.00 0.00 3.61 (0.102) 3.14 (0.089) 1.21 (0.034) 1.34 (0.038) 6.27 (0.178) 4.90 (0.139) 2.19 (0.062) 1.88 (0.053) 0.44 (0.012) 0.41 (0.012) 0.00 0.00 408 DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations—Continued STATION NUMBER 50123100 STATION NAME Rio Quayanilla at Pasto, PR 50124600 Rio Quayanilla near Central Rufina, PR LOCATION AND BASIN Rio Quayanilla basin Lat 18°05'53", long 66°47'38". Hydrologic unit 21010004. At barrio Paste, 1.8 mi (2.9 km) southeast from Pico Rodadero, 1.8 mi (2.9 km) west from Cerro El Peligro, and 5.2 mi (8.4 km) north from Quayanilla Plaza. Lat 18<>01' 00", long 66°47'01". Hydrologic unit 21010004. At Quayanilla, 1.2 mi (1.9 km) upstream from mouth, 0.8 mi (1.3 km) northeast from Central Rufina, and 0.6 mi (1.0 km) southeast from Quayanilla Plaxa. DRAINAGE AREA mi* (km*) 6.45 (16.7) 23.0 (59.5) DATE 3/13/91 4/24/91 3/13/91 4/24/91 TIME 1005 1020 0820 0835 STREAM FLOWS fts/« 2.72 (0.077) 2.60 (0.074) 0.46 (0.013) 0.39 (0.011) 50125000 Rio Yauco near Lago Lucchetti Damsite, PR 50125500 Rio Naranjo near Lago Lucchetti Damsite, PR 50125600 Quebrada Qrande near Lago Lucchetti Damsite, PR 50125860 Rio Duey at Duey, PR 50128450 Quebrada Qrande upstream from Lago Loco, PR 50128500 Rio Loco upstream from Lago Loco, PR 50129200 Quebrada Susua at Palomas, PR 1.92 (4.97) 2.83 (7.33) 4.55 (11.8) 3/13/91 4/24/91 3/13/91 4/24/91 3/13/91 4/24/91 1245 1305 1200 1225 1115 1125 0.27 (0.008) 0.28 (0.008) 0.68 (0.019) 0.41 (0.012) 2.55 (0.072) 2.03 (0.057) Rio Yauco basin Lat 18<>06'40", long 66°52'38". 8.05 3/13/91 1320 2.61 Hydrologic unit 21010004. (20.8) (0.074) Barrio Vegas, 300 ft (91 m) from mouth, 1.5 mi (2.4km) 4/24/91 1350 2.24 northwest from spillway, and (0.063) 5.4 mi (8.7 km) northwest from Yauco Plaia. Lat 18<>06'20", long 66°51'37". Hydrologic unit 21010004. Barrio Naranjo at Rwy 128, 0.3 mi (0.5 km) from mouth and 0.9 mi (1.4 km) from spillway. Lat 18<>06'20", long 66050'56". Hydrologic unit 21010004. Barrio Naranjo, 0.6 mi (1.0 km) west from Hacienda Roig, 0.9 mi (1.4 km) from mouth, and 1.3 mi (2.1 km) from spillway. Lat 18005'44", long 66°50'06". Hydrologic unit 21010004. Barrio Duey, 0.8 mi (1.3 km) southeast from Hacienda Roig, 1.2 mi (1.9 km) east from Lago Lucchetti, and 4.1 mi (6.6 km) from Yauco Plaxa. Rio Loco basin Lat 18°03'45", long 66°53'10". 2.72 3/14/91 1000 0.56 Hydrologic unit 21010004. (7.03) (0.016) Barrio Almacigo Alto, 800 ft (244 m) upstream from confluene with Rio Loco, 1.2 mi (1.9 km) 4/25/91 0925 0.25 north from spillway, and 3.0 mi (0.007) (4.8 km) northwest from Yauco Plaia. Lat 18<>03'22", long 66053'08". 7.66 3/14/91 0920 1.00 Hydrologic unit 21010004. At (19.8) (0.028) barrio Susua Alta, 0.2 mi (0.3 km) upstream from Lago 4/25/91 0850 0.30 Loco, 1.9 mi (3.0 km) north- (0.008) east from Cerro La Torre, and 5.2 mi (8.4 km) southeast from Sabana Grande Plaia. Lat 18<>01'19-, long 66°52'28". 3.23 3/14/91 0820 0.35 Hydrologic unit 21010004. At (8.37) (0.010) bridge on Rwy 2, 0.5 mi (0.8 km) north of Palomas, and 1.9 4/25/91 0750 0.86 mi (3.1 km) southwest of Yauco. (0.024) DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations—Continued 409 STATION NUMBER STATION NAME 50130400 Rio Grande near Sabana Grande, PR 50130500 Rio Guanajibo at La Pica, PR 50130800 Rio Flora* near Sabana Grande,PR 50131010 Rio Cruces near Sabana Grande, PR 50131800 Rio Cupeyes near San German, PR 50132010 Rio Guanajibo below San German, PR 50133000 Rio Cain near San Genan, PR 50133800 Rio Duey near Rosario, PR 50134600 Rio Hbconuco near San Genan, PR 50135000 Rio Hoconuco (Duey) near San German, PR LOCATION AND BASIN Rio Guanajibo basin Lat 18°OS'S3", long 66«S6'18". Hydrologic unit 21010003. Barrio Rln at Hwy 364, 0.5 mi (0.8 km) northeast from Capilla del Pozo de la Virgen, and 1.8 mi (2.9 km) northeast from Sabana Grande Plaza. Lat 18°04'11", long 66«S7'29". Hydrologic unit 21010003. Barrio Rayo at Hwy 2, 1.0 mi (1.6 km) north from Cerro de de los Bonelli, and 0.8 mi (1.3 km) southeast from Sabana Grande Plaza. Lat 18°04'02", long 66«S8'2S". Hydrologic unit 21010003. Barrio Santana at Hwy 2, 0.2 mi (0.3 km) east from Hwy's 2 and 363 intersection, and 0.9 mi (1.4 km) west from Sabana Grande Plaza. Lat 18«04'54-, long 66«58'37". Hydrologic unit 21010003. Barrio Santana at Hwy 2, 400 ft (122 m) west from Hwy 2 and 363 intersection, 1.1 mi (1.8 km) west from Sabana Grande Plaza. Lat 18°04'48", long 67°00'24". Hydrologic unit 21010003. Barrio Guamt, 0.2 mi (0.3 km) downstream from Hwy 2, and 2.5 mi (4.0 km) east from San German Plaza. Lat 18°05'28", long 67°02'38". Hydrologic unit 21010003. 0.5 mi (0.8 km) north of San German Plaza and 1500 ft (457m) downstream from Hwy 360 bridge. Lat 18°06'06", long 67°02'26". Hydrologic unit 21010003. Barrio Cain, at Hwy 361, 600 ft (183 m) upstream from Hwy 2, and 1.3 mi (2.1 km) north from San German Plaza. Lat 18°08'S7", long 67«03'15". Hydrologic unit 21010003. Barrio Duey Alto, 200 ft (61 m) downstream from Hwy 348, 100 ft (30 m) downstream from conflu- ence with Rio Nueve Pasos, and 2.0 mi (3.2 km) southeast from Rosario Plaza. Lat 18°07'08", long 67°04'27». Hydrologic unit 21010003. Barrio Hoconuco Bajo, 0.2 mi (0.3 km) downstream from Hwy 358, 200 ft upstream from confluence with Rio Duey, and 3.2 mi (5.1 km) northwest from San German Plaza. Lat 18°07'10", long 67°04'48'. Hydrologic unit 21010003. Barrio Duey Bajo, 200 ft (61 m) downstream from Hwy 2, and 3.4 mi (5.5 km) northwest from San German Plaza. DRAINAGE AREA mi' (km*) 6.45 (16.7) 14.7 (38.2) 1.98 (5.13) 5.18 (13.4) DATE 3/11/91 4/22/91 3/11/91 4/22/91 3/11/91 4/22/91 TIME 1000 1100 0910 1125 1045 1200 13.2 (34.3) 3/12/91 4/24/91 3/12/91 4/25/91 0845 1245 0915 0835 STREAM FLOWS ftVs (mVs) 0.64 (0.018) 0.00 1.87 (0.053) 1.52 (0.043) 0.06 (0.002) 0.00 4.68 (12.1) 4.16 (10.8) 36.1 193.5) 6.32 (16.4) 4.17 (10.8) 3/11/91 4/24/91 3/12/91 4/24/91 3/12/91 4/23/91 3/12/91 4/24/91 3/12/91 4/23/91 1105 1025 0635 1105 0815 1050 0720 1135 1015 0840 1.11 (0.031) 0.75 (0.021) 0.65 (0.018) 0.48 (0.014) 9.04 (0.256) 3.81 (0.108) 0.33 (0.009) 0.33 (0.009) 0.87 (0.025) 0.50 (0.014) 0.06 (0.002) 0.00 1.08 (0.030) 0.44 (0.012) 410 DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations—Continued STATION NUMBER STATION NAME 50135700 Rio Haricao at Haricao, PR 50135800 Rio Rosario at Las Vegas, PR 50136400 Rio Rosario near Honigueros, PR 50136500 Rio Rosario at Hwy 2 near HormLgueros, PR 50137800 Rio Viejo near Cabo Rojo, PR 50138100 Quebrada maga near Guanajibo, PR 50138200 Rio Hondo near Guanajibo, PR 50138300 Quebrada S£balos near MayagQez, PR 50138900 Rio Yaguez at Balboa, PR LOCATION AND BASIN Lat 18°11'22", long 66°59'37". Hydrologic unit 21010003. Barrio Haricao Afuera, at Hwy 357, 0.4 mi (0.6 km) east from Hacienda San Antonio, and 1.0 mi (1.6 km) northwest from Haricao Plaza. Lat 18°11'13-, long 67°01'52-. Hydrologic unit 21010003. Barrio Montoso, at Hwy 119, 0.1 mi (0.2 km) southeast from intersection with Hwy 105, and 3.6 (5.8 km) northeast from Rosario Plaza. Lat 18°09'36", long 67°05'08-. Hydrologic unit 21010003. At Bridge on Hwy 348, 0.5 mi (0.8 km) Southwest of Rosario Plaza. Lat 18°07'35", long 67°05'39-. Hydrologic unit 21010003. Barrio Benavente, at Hwy 2, 2.7 mi (4.3 km) southwest from Rosario, and 2.5 mi (4.0 km) southeast from HormLgueros Plaza. Lat 18°06'04", long 67°07'48". Hydrologic unit 21010003. Barrio Bajura, at Hwy 103, 1.0 mi (1.6 km) northeast from intersection with Hwy 102, and 1.4 mi (2.2 km) from Cabo Rojo Plaza. Quebrada Haga basin Lat 18°09'18-, long 67°08'07" Hydrologic unit 21010003. Barrio Guanajibo, 0.3 mi (0.5 km) southeast from Hayaguez Hall, and 1.2 mi (1.9 km) northwest from Hormigueros Plaza. Rio Hondo basin Lat 18»09'45-, long 67°09'00". Hydrologic unit 21010003. Barrio Guanajibo, at Hwy 114, 1.8 mi (2.9 km) east from Cerro Cornelia, and 2.0 mi (3.2 km) northwest from Hormigueros Plaza. Quebrada Sabalos basin Lat 18°10'47". long 67°08'58". Hydrologic unit 21010003. Barrio Sabalos, at Hwy 2R, 2.9 mi (4.7 km) northwest from Hormigueros, and 1.7 mi (2.7 km) southwest from MayagOez Plaza. Rio Yaguez basin Lat 18°12'13", long 67°07'55". Hydrologic unit 21010003. 1200 ft (366 m) upstream from bridge on Balboa St. and 1.6 mi (2.6 km) upstream from mouth. DRAINAGE AREA mi* (km*) 3.80 (9.85) 8.33 (21.6) 18.3 (47.4) 22.8 (58.9) 12.3 (31.9) 0.76 (1.96) 3.16 (8.18) 2.47 (6.40) 12.2 (31.6) DATE 3/14/91 4/23/91 3/14/91 4/23/91 3/11/91 4/22/91 3/12/91 4/23/91 3/15/91 4/23/91 3/13/91 4/23/91 3/13/91 4/25/91 3/13/91 4/25/91 3/13/91 4/25/91 TIME 1030 0700 1120 0750 1235 1250 1155 1010 0800 1145 1100 1215 1130 0705 1200 0640 1235 0600 STREAM FLOWS ftVs (mVs) 2.26 (0.064) 2.58 (0.073) 5.68 (0.161) 4.39 (0.124) 9.44 (0.267) 7.71 (0.218) 9.14 (0.259) 7.16 (0.203) 1.22 (0.035) 1.62 (0.046) 0.00 0.00 0.18 (0.005) 0.18 (0.005) 0.38 (0.011) 0.32 (0.009) 3.36 (0.095) 3.73 (0.106) DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations—Continued 41 1 STATION NUMBER STATION NAME 50140300 Rio Quilarte near Adjuntas, PR 50140800 Rio Liaani n« Yabuecas, PR 50141400 Rio Ouayo at Guayo, PR 50142000 Rio Blanco at La Torre, PR 50142100 Quebrada de Los Platanos at Marisol, PR 50142300 Rio Prieto at Indiera Alta, PR 50142710 Rio Prieto at Rio Prieto, PR 50142900 Rio Prieto at Pesuela, PR 50143000 Rio Orande de Afiasco near Lares, PR 50143104 Rio Lajas near Maricao, PR LOCATION AND BASIN Rio Qrande de Afiasco basin Lat 18°10'58", long 66°46'09". Hydrologic unit 21010003. Barrio Guilarte at Hwy 131, 0.4 mi (0.6 km) southwest from Hwy's 130 and 131 intersection, and 4.3 mi (6.9 km) east from Castaffer. Lat 18«12'01", long 66°47'50 <> . Hydrologic unit 21010003. Barrio Yahuecas, 200 ft (61 m) upstream with Rio Quilarte, and 500 ft (152 m) southwest from Hwy's 129 and 135 intersection. Lat 18«10'49", long 66°49'40-. Rydrologic unit 21010003. Barrio Guayo at Hwy 131, 1.0 mi (1.6 km) upstream from Lago Ouayo, 0.4 mi (0.6 km) southeast from Castafier. Lat 14«18'34", long 66«51'49". Rydrologic unit 21010003. Barrio La Torre, at Hwy 128, 2.7 mi (4.3 km) northwest from Lago Guayo, and 4.5 mi (7.2 km) northwest from Castafier. Lat 18«15'41", long 66«51'22". Rydrologic unit 21010003. Barrio Marisol, at Hwy 128, 0.3 mi (0.5 km) south from Hwy's 128 and 129 intersection. Lat 18«10'07", long 66«51'49". Rydrologic unit 21010003. Barrio Indiera Alta, at Hwy 128, 2.3 mi (3.7 km) southwest from Lago Guayo, and 2.2 mi (3.5 km) southwest from Castafier. Lat 18<> 12'06', long 66°53'05". Rydrologic unit 21010003. Barrio Rio Prieto, at Hwy 431, 3.7 mi (5.6 km) west from Lago Guayo, and 6.4 mi (10 km) northeast from Maricao Plaza. Lat 18«15'17", long 66°54'25". Rydrologic unit 21010003. Barrio Pesuela, 400 ft (122 m) upstream from confluence with Rio Grande de Afiasco, and 3.4 mi (5.5 km) southwest from Lares Plasa. Lat 18«15'28", long 66°55'05". Rydrologic unit 21010003. At bridge on Hwy 124, 0.7 mi (1.1 km) from confluence with Rio Blanco and Rio Prieto, and 3.7 mi (6.0 km) southwest from Lares Plasa. Lat 18°10'54", long 66°57'39-. Rydroloigc unit 21010003. Barrio Indiera Frla, at Hwy 105, 0.3 mi (0.5 km) upstream from confluence with Rio Guaba, 0.7 mi (1.1 km) Maricao Plasa. DRAINAGE AREA mi* (km») 2.62 (6.78) DATE 3/12/91 4/23/91 TIME 0830 1000 26.3 (68.1) 5.79 (15.0) 3/12/91 4/24/91 3/12/91 4/23/91 1310 0720 0720 1410 STREAM FLOWS ftVs (mVs) 2.83 (0.080) 1.88 (0.053) 7.38 (19.1) 4.15 (10.7) 33.2 [86.0) 0.57 (1.47) 7.47 (19.3) 15.1 [39.0) 26.1 [67.7) 3/12/91 4/23/91 3/12/91 4/23/91 3/11/91 4/24/91 3/15/91 4/24/91 3/11/91 4/24/91 3/11/91 4/25/91 3/12/91 4/24/91 0925 1100 1115 1300 1710 1115 1025 1010 1430 1335 1540 1245 1530 0830 5.30 (0.150) 3.64 (0.103) 3.35 (0.095) 2.09 (0.059) 20.5 (0.059) 12.4 (0.351) 0.28 (0.008) 0.48 (0.014) 6.27 (0.178) 3.10 (0.088) 1.85 (0.052) 0.85 (0.024) 8.58 (0.243) 6.03 (0.171) 29.2 (0.827) 19.9 (0.564) (0.240) 3.26 (0.092) 2.22 (0.063) 412 DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations--Continued STATION NUMBER STATION NAMB 50143108 Rio Ghiaba near Maricao, PR 50143150 Rio Bucarabones Las Marias, PR 50143200 Rio Ghiaba near Las Marias, PR 50143400 Quebrada Las Cafias at Perchas, PR 50143500 Rio Mayaguecilla at Las Marias, PR 50143800 Rio Grand* de Afiasco near Las Marias, PR 50143900 Rio Arena* at Las Marias, PR 50144200 Quebrada Cerro Oordo near Cerro Oordo, PR 50144900 Rio Humata near Bl Bspino, PR 50145000 Rio Grand* de Afiasco at Bl Bspino, PR LOCATION DRAINAGE STREAM AREA FLOWS AND mi 1 DATE TIME ftj/s (km*) (»*/•) BASIN Lat 18°11'02", long 66°57'30". 4.95 3/12/91 0820 4.19 Hydrologic unit 21010003. (12.8) (0.119) Barrio Bucarabones, at Bwy 105, 200 ft (61 m) upstream 4/23/91 1755 2.77 from confluence with Rio (0.078) Lajas, and 1.5 mi (2.4 km) from Maricao Plata. Lat 18°13'27", long 66°56'41". 9.19 3/12/91 1155 5.81 Hydrologic unit 21010003. (23.8) (0.164) Barrio Bucarabones, 400 ft (122 m) upstream from 4/23/91 1210 4.69 confluence with Rio Ghiaba, (0.133) and 3.7 mi (5.6 km) northeast from Maricao Plaxa. Lat 18°13'37", long 66°56'33 a . 25.4 3/12/91 1045 15.8 Hydrologic unit 21010003. (65.7) (0.447) Barrio Cerrote, at Hwy 124, 0.3 mi (0.5 km) downstream from 4/23/91 1120 11.0 confluence with Rio Bucarabones, (0.312) and 3.9 mi (6.3 km) northeast from Maricao Plaxa. Lat 18«16'23", long 66°56'36". 3.08 3/15/91 0840 2.40 Hydrologic unit 21010003. (7.98) (0.068) Barrio Perchas No 2, at Hwy 434, 800 ft (244 m) upstream from 4/23/91 0910 2.25 confluence with Rio Grande de (0.064) Annasco, and 3.5 mi (5.6 km) from Las Marias Plaxa. Lat 18«14'50", long 66°59'05 a . 3.30 3/12/91 0955 0.09 Hydrologic unit 21010003. (8.54) (0.002) Barrio Palma Escrita, at Hwy 124, 2.0 mi (3.2 km) upstream from 4/23/91 1030 0.02 confluence with Rio Grand* de (0.001) Afiasco, and 0.7 mi (1.1 km) southeast fron Las Marias Plaxa. Lat 18«16'41", long 66°58'48". 116 3/15/91 0725 60.6 Hydrologic unit 21010003. (299) (1.716) Barrio Ouacio, at Hwy 119, 1.8 mi (2.9 km) northeast 4/23/91 0755 51.2 from Las Marias Plaxa. (1.450) Lat 18°15'10", long 66°59'57". 2.79 3/13/91 1400 3.28 Hydrologic unit 21010003. (7.22) (0.093) Barrio Maravillas, at Hwy 119, 0.5 mi (0.8 km) southwest from 4/23/91 0640 2.73 Las Marias Plaxa. (0.077) Lat 18«17'09", long 66°04'09 a . 2.66 3/13/91 1025 2.22 Hydrologic unit 21010003. (6.89) (0.063) Barrio Corcovada, 600 (183 m) upstream from confluence with 4/25/91 0800 2,02 Rio Orande de Afiasco, and 5.7 (0.057) mi (9.2 km) from Las Marias, and 4.8 mi (7.7 km) east from Afiasco Plasa. Lat 18<>17'18-, long 67°06'24'. 4.86 3/13/91 1125 3.12 Hydrologic unit 21010003. (12.6) (0.088) Barrio Carreras, at Hwy 109, 0.3 mi (0.5 km) upstream from 4/25/91 0900 1.38 confluence with Rio Gtrande de (0.039) Afiasco, and 2.4 mi (3.9 km) east from Afiasco Plata. Lat 18«16'50", long 67°06'46 a . 108 3/13/91 1230 91.8 Hydrologic unit 21010003. (280)-384 (2.560) Barrio Bspino, at Hwy 406, 400 ft (249 m) east from 4/25/91 0955 67.8 intersection with Hwy 109, (1.920) and 1.9 mi (3.1 km) from Afiasco Plata. DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations—Continued 413 STATION NDHBBR STATION NAME 50145400 Rio Case! Mar Mayagues, PR 50146000 Rio Grande de Afiasoo at Afiasoo Arriba, PR 50146002 Rio Caftas at Rio Caftas Arriba, PR 50146005 50146075 Rio Caftas at Rio Cafias Abajo, PR Rio Daguey near Afiasoo, PR 50146200 Rio Grand* near Rinc6n, PR 50146300 50146400 Rio Ingenio at Jaguey, PR Rio Ingenio near Aguada, PR 50146600 Rio Culebra near Aguada, PR LOCATION AND BASIN Lat 18«15'18", long 67°04'48". Bydrologic unit 21010003. Barrio Leguisamo, at Bwy 108, 4.6 mi (7.4 lot) northeast from Mayaues, and 4.5 mi (7.2 km) southeast from Mayagues Plaza. Lat 18<>16'31-, long 66«07'37". Bydrologio unit 21010003. 0.8 mi (1.2 km) south of Afiasoo and 3.0 Hi (4.8 km) upstream from mouth. Lat 18»13'37», long 67°04'01». Bydrologio unit 21010003. Barrio Cafias Arriba, at Hwy 354. 0.2 Hi (0.3 km) south from intersection with Buy 355. and 5.1 mi (8.2 km) from Mayagues Plasa. Lat 18«14'38", long 67«07'17". Bydrologic unit, 21010003. Barrio Rio Cafias Abajo, at Hwy 108, and 3.1 mi (5.0 km) north- east from MayagueE Plasa. Lat 18<>17'19-, long 67«08'08". Bydrologic unit 21010003. Barrio Carreras, at Hwy 405, 100 ft (30 m) east from intresection with Hwy 404, and 0.5 mi (0.8m) northeast from Mayagues Plasa. Rio Grande basin Lat 18<>22'06-, long 67°13'56". Bydrologic unit 21010003. At bridge on Hwy 115, 1.2 mi (1.9 km) upstream from mouth, and 2.2 Hi (3.5 km) northeast of Rinc6n. Rio Ingenio basin Lat 18°20'36", long 67°11'52". Bydrologic unit 21010003. Bario Jaguey, at unmunbered Hwy, 0.3 Hi (0.5 km) from Hwy 411 intersection, and 2.7 mi (4.3 km) southwest from Aguada Plasa. Lat 18°22'48", long 67°12'35". Hydrologic unit 21010003. At bridge on unimproved road, 0.3 mi (0.5 km) upstream from con- fluence with Rio Culebra, 0.7 mi (1.1 km) upstream from mouth of Rio Guayabo, and 1.4 mi (2.3 km) west of Aguada. Rio Culebra basin Lat 18°22'26", long 67°11'35". Bydrologic unit 21010003. At bridge on Hwy 411, 0.6 mi (1.0 km) south of Aguada, 1.5 mi (2.4 km) upstream from conflu- ence with Rio Ingenio, and 1.9 mi (3.1 km) upstream from mouth of Rio Guayabo. DRAINAGE AREA mi* (km») 8.17 (21.2) 161 (416) 3.58 (9.26) DATE 3/13/91 4/24/91 3/14/91 4/22/91 3/13/91 4/25/91 TIME 0905 1600 0700 1500 0755 0640 STREAM FLOWS ft*/ s (m3/.) 6.93 (0.392) 5.30 (0.150) 92.7 (2.625) 81.1 (2.297) 2.26 (0.064) 1.73 (0.049) 11.2 (29.1) 1.06 (2.75) 2.83 (7.33) 3.18 (8.22) 7.00 (18.1) 3/13/91 4/24/91 3/14/91 4/22/91 3/14/91 4/22/91 3/14/91 4/22/91 3/14/91 4/22/91 0635 1655 0800 1430 1240 1330 1035 1125 1150 1230 3.75 (9.70) 3/14/91 4/22/91 0910 1030 2.57 (0.073) 2.09 (0.059) 0.31 (0.009) 0.27 (0.008) 0.49 (0.014) 0.29 (0.008) 1.21 (0.034) 1.29 (0.036) 2.59 (0.073) 1.58 (0.045) 1.18 (0.033) 0.81 (0.023) 414 DISCHARGE AT CRBST- STAGS PARTIAL-RECORD STATIONS The following table contains annual ••"<"•"• discharge for crest-stag* stations. A crest-stag* gag* is a device which will register the peak stage occurring between inspections of the gage. A stage-discharge relation for each gage is developed from discharge measurements made by indirect measurements of peak flow or by current meter. The date of the — — -f— IT discharge is not always certain but is usually determined by comparison with nearby continuous- record stations, weather record, or local inquiry. Only the — •»•<— i- discharge for each water year is given. Infor- mation on some lower floods may have been obtained, and discharge measurements may have been made for purposes of establishing the stage- discharge relation, but these are not published herein. The years given in the period of rec- ord represent years for which the annual maximum has been determined. Annual maximum discharge at crest-stage partial-record stations during water year 1991 Station nitmn and number Location and drainage area Water year 1991 maximum ~"~~ Gage Dis- Period Date height charge of ft ftVs record (m) (m'/s) Period of record marlimiin Date Gage height ft (m) Dis- charge ftVs (m'/s) Quebrada Yeguas near Salinas, PR (50100600) Rio Salinas Basin Lat 18°01'57", long 66°13'30", 1989-91 10-20-90 Rydrologic Unit 21010004, on right bank, 350 ft (107 m) upstream bridge on Highway 712, 1.4 mi (2.2 km) southwest of La Plena, 1.6 mi (2.6 km) southeast of Camp Santiago and 1.7 mi (2.7 km) northwest of Ouayama municipal limit. Drainage area is 2.66 mi1 (6.89 km3 ). 11.90 (3.627) 1,310 (37.10) 10-20-90 11.90 (3.627) 1,310 (37.10) 415 Water-Quality at Partial-Record Stations in Puerto Rico 416 ANALYSES OF SAMPLES COLLBCTBD AT WATER-QUALITY PARTIAL-RBCORD STATION Water-quality partial-record itationi arc partiocular litei where chemical-quality, biological and or ledimant data are collected lyiteaatioally over a period of yeari for me in hydrological analyiii. The data are collected unially le» than quarterly. WATBR-QDALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 DATE 50010720 NOV 1990 28... MAR 1991 27... JUL 12... TIME LAGO 0930 0935 0810 DEPTH AT SAMPLE LOC- ATION, TOTAL (FEET) GUAJATACA 1.00 1.00 1.00 8PB- TRANS- CIFIC PAR- CON- PH TEMPER- BNCY OXYGEN, DUCT- (STAND- ATURB (SECCHI DI8- ANCE ARD WATER DISK) SOLVED (US/CM) UNITS) (DBG C) (IN) (MG/L) RIO GUAJATACA BASIN NO. 3 NR MOUTH NR QUEBRADILLAS,PR (LAT 18°22' 269 325 262 6.8 7.6 7.2 27.7 28.5 29.0 99 81 31 .6 .0 .2 8. 8. 9. 2 2 3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 05-N LONG 103 105 122 COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) 066°54'36 BW) 20 26 39 RIO QRANDB DB ARBCIBO BASIN 50025110 NOV 1990 26... MAR 1991 25... JUL 17... 50039900 NOV 1990 23... MAR 1991 20... JUL 09... 50044400 NOV 1990 21... MAR 1991 19... JUL 10... 50057500 NOV 1990 19... MAR 1991 21... JUL 15... LAGO 0900 0940 0845 LAGO 0815 0855 0825 LAGO 0915 0845 0800 LAGO 1155 0900 0945 DOS BOCA8 1.00 1.00 1.00 CARITB NO. 1.00 1.00 1.00 NO. 3 AT WEST BRANCH NR UTUADO, 222 238 255 RIO DB 3 ON RIO DB 127 133 145 5.9 7.7 7.8 26.5 26.0 28.0 51 30 37 PR (LAT .6 .0 .2 18° 19' 11. 8. 6. 9 3 9 15-N LONG 145 99 88 066°40'11 BW) 160 K350 K400 LA PLATA BASIN LA PLATA 5.9 7.8 7.4 NR CAYBY, 24.3 27.0 26.8 LA PLATA NO. 5 NR MOUTH NR NARAMJITO, 1.00 1.00 1.00 LOIZA NO. 4 1.00 1.00 1.00 344 336 421 RIO GRANDB 6.2 7.8 6.4 DB LOIZA NR MOUTH NR CAGUAS, 327 259 391 6.4 6.6 6.2 27.0 24.6 28.5 BASIN 54 42 48 PR 30 24 14 PR (LAT .0 .0 .0 18o 6. 8. 7. (LAT 18<>19' .0 .0 .4 11. 9. 1. 05' 8 4 9 33- 3 1 8 PR (LAT 18° 16' 51 "N LONG 28.5 27.0 29.0 23 7 33 .4 .0 .6 6. 5. 1. 0 0 9 04-N LONG 86 93 84 066°06'03-W) 11 19 15 N LONG 066°12'28"W) 139 108 23 066°00'35 76 62 24 K130 K250 K7 •W) 2900 550 160 K « non-ideal count 417 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATION WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DATE 50010720 NOV 1990 28... MAR 1991 27... JUL 12... 50025110 NOV 1990 26... MAR 1991 25... JUL 17... 50039900 NOV 1990 23... MAR 1991 20... JUL 09... 50044400 NOV 1990 21... MAR 1991 19... JUL 10... 500S7500 NOV 1990 19... MAR 1991 21... JUL 15... STREP- TOCOCCI FECAL, KF AQAR (COLS. PER 100 ML) LAOO 13 12 49 LAOO 93 180 130 LAOO 160 26 8 LAOO K14 94 52 LOIZA 108 54 K20 ALKA- RESIDUE LINITY TOTAL NITRO- NITRO- NITRO- NITRO- WAT WH AT 105 GEM, GEN, GEN, GEN, TOT PET DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA FIELD BUS- TOTAL TOTAL TOTAL TOTAL MG/L AS PBNDBD (MQ/L (MG/L (HG/L (MG/L CACO3 (MG/L) AS N) AS N) AS N) AS N) RIO GUAJATACA BASIN- -Continued GUAJATACA NO. 3 NR MOUTH NR QUEBRADILLAS, PR (LAT 18°22 130 <1 — <0.010 <0.100 0.040 140 6 0.090 0.020 0.110 0.020 100 1 — < 0.010 <0.050 0.060 RIO GRANDS DB ARBCIBO BASIN— Continued DOS BOCAS NO. 3 AT WEST BRANCH NR UTUADO,PR (LAT 18° 19 77 <1 0.680 0.020 0.700 0.050 80 2 0.390 0.020 0.410 0.030 75 5 0.150 0.010 0.160 0.030 RIO DB LA PLATA BASIN— Continued CARITB NO. 3 ON RIO DB LA PLATA NR CAYBY, PR (LAT 18°05 31 2 — 0.010 <0.100 0.110 39 7 — <0.010 04'39-N LONG 64.8 -- 55.0 -- 49.0 — , PR (LAT 18°20 .5 .0 .5 .5 .0 .5 38.4 -- 55.0 -- 62.4 — 7.8 1.8 10.1 2.3 8.8 0.8 066° 06' 19" 98 23 126 29 116 1 W) 16— K10— K3— 79 -- K10 -- 190 — '18-N LONG 0660 14'01'W) 11.0 2.4 6.9 2.6 4.6 0.1 137 30 81 31 60 1 150— K7— K17— K4— 170 — 58 — LOIZA BASIN- -Continued NR TRUJILLO ALTO, PR 5.9 6.0 6.8 6.7 6.2 6.1 29 27 26 25 29 29 .0 .0 .0 .0 .0 .0 (LAT 18»19'29"N 40.8 -- 10.0 -- 23.4 — 8.9 1.5 4.8 2.8 3.2 1.9 LONG 0660 00'47"W) 114 19 59 34 41 24 54— 120— K170— K4 -- K15 — 27 -- non-ideal count 420 MISCELLANEOUS STATION ANALYSES DATE 50010790 NOV 28. 28. MAR 27. 27. JUL 12. 12. 1990 . . 1991 . . . . •• 50020050. NOV 27. 27. MAR 26. 26. JUL 11. 11. 1990 . . 1991 . . . . . . • • 50027090 NOV 26. 26. MAR 25. 25. JUL 17. 17. 1990 . . 1991 . . . . •• 50039950 NOV 23. 23. MAR 20. 20. JUL 09. 1990 . , 1991 . . . . •• 50044950 NOV 21. 21. MAR 19. 19. JUL 10. 10. 1990 . . . . 1991 . . . . •• 50058800 NOV 19. 19. MAR 21. 21. JUL 15. 15. 1990 . . . . 1991 . . . . . . HARD- NESS TOTAL (MG/L AS CAC03) LAGO 140 160 150 160 150 £6 LAGO 59 53 67 67 69 130 LAOO 74 74 85 81 81 81 LAGO 38 29 31 32 35 LAGO 110 54 110 110 110 130 LACK) 82 •5 100 100 97 94 HARD- NESS MAGNB- SODIUM POTAS- NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WH WAT DIS- DIS- DIS- SORP- DIS- TOT FLD SOLVED SOLVED SOLVED TION SOLVED MG/L AS (MO/L (MQ/L (MG/L RATIO (MG/L CACO3 AS CA) AS MO) AS NA) AS K) RIO GUAJATACA BASIN- -Continued QUAJATACA NO.l NR DAM NR QUEBRADILLAS,PR (LAT 18°23'S6" 49 60 53 57 55 18 RIO GRANDB DB GARZAS NO.l NR DAM 17 15 19 19 19 45 3.8 3.6 4.1 4.0 3.4 5.1 6.3 5.5 £.3 6.3 5.1 6.3 0. 0. 0. 0. 0. 0. 2 2 2 2 2 3 2.2 1.7 1.9 2.0 1.8 1.0 ALKA- LINITY NAT WH SULFATB TOT FBT DIS- FIBLD SOLVED MG/L AS (MG/L CACO3 AS SO4) 'N LONG 066°55'23"W) 130 160 120 140 150 110 8 3 16 10 8 2 .5 .2 .3 .9 ARBCIBO BASIN- -Continued NR ADJUNTAS,PR 4.1 3.7 4.8 4.8 5.3 4.0 6.2 5.5 6.6 6.3 6.3 5.9 DOS BOCA8 NO.l NR DAM NR UTUADO,PR 20 20 23 22 22 22 RIO DB LA CARITB NO.l NR DAM 8.6 6.3 6.9 7.0 6.9 5.9 5.8 6.7 6.3 6.4 6.4 9.5 9.6 12 10 11 11 (LAT 18°08'21 >N LONG 0. 0. 0. 0. 0. 0. 4 3 4 3 3 2 (LAT 18°20'09" 0. 0. 0. 0. 0. 0. 5 5 6 5 5 5 1.1 1.2 1.1 1.2 1.4 2.0 066*44 '35' 56 61 59 65 80 70 W) 2 3 2 2 8 11 .6 .0 .3 .8 .2 N LONG 066°40'04 >W) 2.0 1.8 2.0 2.1 2.0 2.2 72 70 75 82 -- 190 8 13 15 12 14 15 .9 PLATA BASIN — Continued NR CAYBY, 4.0 3.2 3.4 3.5 4.4 P.R. 7.9 7.9 7.8 8.1 9.0 LA PLATA NO. 3 NR DAM NR NARANJITO, 26 13 26 27 27 30 RIO ORANDB 11 5.3 10 11 10 13 DB LOIZA 21 10 14 17 15 20 (LAT 18<>04' 39 "N LONG 0. 0. 0. 0. 0. PR (LAT 0. 0. 0. 0. 0. 0. 6 6 6 6 7 18<>20' 9 6 6 7 6 8 1.0 0.80 1.0 0.80 0.80 066°06'19" 54 31 19 30 56 18 "N LONG 06 6° 14 2.2 2.3 3.0 2.3 2.9 1.7 110 51 87 44 120 130 W) <1 3 2 2 3 '01 13 6 13 13 7 14 .0 .0 .7 .8 .0 •W) .7 .1 BASIN- -Continued LOIZA NO. 7 NR DAM NR TRUJILLO ALTO 20 22 25 25 25 24 7.7 7.2 9.3 9.4 8.3 8.3 18 17 23 25 26 25 , PR (LAT 18° 19 0. 0. 1 1 1 1 9 8 '29"N 3.0 3.3 2.6 2.7 4.6 4.6 LONG 066»00'47"W) 84 82 50 44 100 100 12 9 18 19 20 19 .3 421 DATE 50010790 MISCELLANEOUS STATION ANALYSES SOLIDS, RESIDUE CHLO- FLOO- SILICA, SOU OF TOTAL NITRO- NITRO- NITRO- NITRO- RIDB, RIDE, DIS- CONSTI- AT 105 GEN, GEN, GEN, GEN, DIS- DIS- SOLVED TUENTS, DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA SOLVED SOLVED (MG/L DIS- SUS- TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L AS SOLVED FENDED (MG/L (MG/L (MG/L (MG/L AS CL) AS F) SI02) (MG/L) (MG/L) AS N) AS N) AS N) AS N) RIO GUAJATACA BASIN—Continued LAGO GUAJATACA NO.l NR DAM NR QUBBRADILLAS,PR (LAT 18°23'56"N LONG 066°55'23"W) NOV 1990 28... 28... MAR 1991 27... 27... JUL 12... 12... 50020050 NOV 1990 27... 27... MAR 1991 26... 26... JUL 11... 11... 50027090 NOV 1990 26... 26... MAR 1991 25... 25... JUL 17... 17... 7.2 5.0 11 10 6.2 9.1 LAGO 5.5 5.5 5.8 6.3 12 9.0 LAGO 9.7 8.7 11 12 13 13 0 0 0 0 0 0 .20 .20 .10 .10 .10 .20 GARZAS NO. 0 0 <0 <0 0 0 .20 .20 .10 .10 .30 .10 DOS BOCAS 0 0 0 <0 0 0 .20 .20 .10 .10 .30 .30 6 7 6 7 19 7 RIO 1 NR 18 21 21 22 6 21 NO.l 22 24 20 23 21 21 .4 162 .6 183 .8 171 .9 181 125 .0 180 <1 — 3 — 6 — -- -- -- -- -- <0.010 -- 0.010 — 0.010 — 0.100 -- <0.050 -- <0.050 — 0. - 0. - 0. - 040 - 020 - 070 - GRANDB DB ARBCIBO BASIN- -Continued DAM NR ADJUNTAS,PR (LAT 89 91 96 101 .7 129 118 1 — <1 — 2 — 18<>08' -- -- -- -- --— NR DAM NR UTUADO,PR (LAT 18°20 124 122 135 137 136 205 <1 — 2 — 17 — 0.490 -- -- -- 0.087 — 21-N LONG <0.010 — 0.010 — •cO.010 — '09"N LONG 0.010 — <0.010 -- 0.010 — 066°44' <0.100 -- <0.050 — <0.050 — 066°40 0.500 — 0.210 -- 0.097 — 35-W) 0. - 0. - 0. - '04"W) 0. - 0. - 0. - 030 - 010 - 060 - 030 - 020 - 010 - RIO DB LA PLATA BASIN— Continued 50039950 NOV 1990 23... 23... MAR 1991 20... 20... JUL 09... 09... 50044950 NOV 1990 21... 21... MAR 1991 19... 19... JUL 10... 10... 50058800 NOV 1990 19... 19... MAR 1991 21... 21... JUL 15... 15... LAGO 10 9.9 10 9.6 10 9.2 LAGO 38 10 19 17 24 18 LAGO 18 17 23 23 29 28 CARITB NO. 0 0 0 0 0 0 .20 .20 .20 .20 .10 .10 1 NR 16 17 18 19 19 20 DAM NR CAYBY, 66 59 68 62 87 81 P.R. (LAT <1 -- 4 — 12 -- LA PLATA NO. 3 NR DAM NR NARANJITO, PR 0 0 0 0 0 0 LOIZA <0 0 0 0 0 0 .20 .20 .10 .10 .10 .10 NO. 7 .10 .20 .10 .10 .10 .10 20 16 17 20 18 20 197 94 133 155 199 172 RIO GRANDB DE NR DAM NR TRUJILLO 26 25 29 29 28 28 152 153 160 160 201 197 <1 — 6 — 4 — 18°04'39"N LONG -- -- 0.057 -- -- -- 0.010 — 0.010 — <0.010 — 066°06' <0.100 — 0.067 -- <0.050 — 19-W) 0. - 0. - <0. - (LAT 18°20'18"N LONG 066°14'01 0.180 -- -- -- --— 0.020 — <0.010 — <0.010 — 0.200 -- <0.050 -- <0.050 — 0. - 0. - 0. - 090 - 020 - 010 - "W) 040 - 020 - 050 - LOIZA BASIN— Continued ALTO, PR 21 — 26 — 13 — (LAT 18«19'29-N 0.420 -- 0.500 -- 0.130 — 0.080 — 0.090 — 0.090 — LONG 0660 00'47"H) 0.500 -- 0.590 — 0.220 — 0. - 0. - 1. - 050 - 050 - 10 - 422 DATE 50010790 MISCELLANEOUS STATION ANALYSES NITRO- CHLOR-A CHLOR-B NITRO- GEN, AM- PHYTO- PHYTO- QEN, MONIA + NITRO- NITRO- PHOS- PLANK- PLANK- PLANK- PLANK- OROANIC ORQANIC QBN, QBN, PHORUS TON TON TON TON TOTAL TOTAL TOTAL TOTAL TOTAL CHROMO CHROMO BIOMASS BIOMASS (MG/L (MG/L (MG/L (MG/L (MG/L FLUOROM FLDOROM ASH WT DRY WT AS N) AS N) AS N) AS NO3) AS P) (OG/L) (OG/L) (MG/L) (MG/L) RIO GUAJATACA BASIN—Continued LAGO GUAJATACA NO.1 NR DAM NR QUEBRADILLAS,PR (LAT 18°23'56-N LONG 066°55'23"W) NOV 28. 28. MAR 27. 27. JUL 12. 12. 1990 . . . . 1991 . . . . . . . . 0.26 — 0.38 — 0.33 — 0.30 -- 0.40 -- 0.40 -- 0.40 — —— —— 1.8 — — -- -- -- 0.040 — 0.020 — 0.020 — 3.30 -- 2.00 -- 3.20 -- 0 <0 0 .200 — .100 — .400 — 3.4 — 2.4 -- 2.5 -- 240— 250— 260— RIO GRANDB DB ARBCIBO BASIN— Continued 50020050 NOV 27. 27. MAR 26. 26. JUL 11. 11. 1990 . . . . 1991 . . . . . . •• 50027090 NOV 26. 26. MAR 25. 25. JUL 17. 17. 1990 . . . . 1991 . . . . . . •• 50039950 NOV 23. 23. MAR 20. 20. JUL 09. 09. 1990 . . . . 1991 . . . . •• 50044950 NOV 21. 21. MAR 19. 19. JUL 10. 10. 1990 . . . . 1991 . . . . . . •• 50058800 NOV 19. 19. MAR 21. 21. JUL 15. 15. 1990 . . . . 1991 . . . . . . . . LAGO 0.27 — 0.39 -- 0.44 — LAGO 0.37 — 0.38 — 0.49 — LAGO 0.41 -- —— —— LAGO 0.46 — 0.48 -- 0.45 — LAGO 0.75 — 0.35 — 1.1 — GARZAS NO 0.30 — 0.40 -- 0.50 — DOS BOCAS 0.40 -- 0.40 — 0.50 — CARITB NO 0.50 -- <0.20 -- 0.40 — .1 NR DAM NR —— — -- --— NO.l NR DAM 0.90 — 0.61 — 0.60 — RIO DB LA .1 NR DAM NR — -- —— — -- ADJUNTAS,PR (LAT -- __ -- -- --— <0.010 — 0.020 -- 0.010 — 180Q8' 3.10 __ 1.20 -- 16.0— NR UTUADO,PR (LAT 18°20 4.0 __ 2.7 __ 2.6 — PLATA CAYBY, — -- —— —— 0.010 — <0.010 — 0.010 — 11.0 __ 1.70 __ 3.90 — 21"N 0 <0 0 LONG .200 — .100 -- .400 — '09-N LONG 0 <0 0 .200 — .100 — .400 — 066°44 '35" 1.6 -- 2.4 -- 2.5 — 066°40'04 1.6 -- 2.4 -- 2.5 — W) 250— 250-- 250— "W) 240— 250— 250— BASIN--Continued P.R. (LAT <0.010 __ 0.030 — 0.020 — LA PLATA NO. 3 NR DAM NR NARANJITO, PR 0.50 -- 0.50 -- 0.50 — LOIZA NO. 0.80 __ 0.40 -_ 2.2 -- 0.70 — —— —— RIO GRANDS 7 NR DAM NR 1.3 __ 0.99 __ 2.4 — 3.1 — — __ __— 0.020 — 0.040 __ 0.020 ~ 18°04' 3.50 __ 4.50 — 13.0 — 39-N 0 1 3 (LAT 18020' 6.10 __ — __ 20.0 -- 0 1 LONG .500 — .40 — .60 -- 066°06'19" 1.4 -- 2.2 -- 2.4 — W) 230— 230— 250 -- 18 "N LONG 066oi4'01"W) .400 — — __ .10 ~ 2.2 -- 2.3 __ 2.5 — 240— 220 -- 260— DB LOIZA BASIN- -Continued TRUJILLO ALTO, PR (LAT 18° 19 5.8 __ 4.4 __ 11— 0.110 __ 0.240 __ 0.470 — 9.60 __ 9.40 __ 17.0 __ 0 0 2 '29"N .400 __ .200 __ .20 — LONG 066°00' 47 "W) 2.6 __ 2.5 __ 2.5 __ 250 __ 260 __ 260— K • non-ideal count 423 DATS 50010790 J0L 1991 12... 50039950 J0L 1991 09... 50044950 J0L 1991 10... 50058800 PRSTICIDB ANALYSES OF SAMPLES COLLBCTBD AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 CHLOR- DI- DI- BNDO- PCB, ALDRIN, DANE, DDD, DDE, DOT, AZINON, BLDRIN SULFAN, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (OQ/L) (DQ/L) (DQ/L) (OG/L) (DQ/L) (DQ/L) (DO/L) (DQ/L) (DQ/L) RIO OOAJATACA BASIN—Continued LACK) OTJAJATACA NO.1 NR DAM NR QOEBRADILLAS,PR (LAT 18°23'56'N LONG 066°55'23'W) 0840 <0.1 <0.010 <0.1 <0.010 <0.010 <0.010 <0.01 <0.010 <0.010 RIO DB LA PLATA BASIN—Continued LAGO CARITB NO.l NR DAM NR CAYEY, P.R. (LAT 18°04'39'N LONG 066<*06'19"W) 0855 <0.1 <0.010 <0.1 <0.010 <0.010 <0.010 <0.01 <0.010 <0.010 LAGO LA PLATA NO.3 NR DAM NR NARANJITO, PR (LAT 18°20'18"N LONG 066°14'01 -W) 0905 <0.1 <0.010 <0.1 <0.010 <0.010 <0.010 <0.01 <0.010 <0.010 RIO GRANDB DB LOIZA BASIN—Continued LAGO LOIZA NO.7 NR DAM NR TRDJILLO ALTO, PR (LAT 18°19'29"N LONG 066°00'4VW) JOL 1991 15... 0910 <0.010 <0.010 <0.010 <0.010 0.01 <0.010 <0.010 424 PESTICIDE ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER-QUALITY DATA, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 HEPTA- MBTH- METHYL HEPTA- CHLOR MALA- OXY- PARA- ENDRIN, ETHION, CHLOR, BPOXIDB LINDANB THION, CHLOR, THION, MIREX, DATE TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (OQ/L) (OQ/L) (UQ/L) (UG/L) (UG/L) (OQ/L) (UG/L) (UG/L) 50010790 JUL 1991 12... 50039950 50044950 50058800 JDL 1991 15... RIO GUAJATACA BASIN—Continued LAGO GUAJATACA NO.1 NR DAM NR QUEBRADILLAS,PR (LAT 18°23'56"N LONG 066°55'23"W) <0.010 <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 <0.01 RIO DB LA PLATA BASIN—Continued LAGO CARITB NO.l NR DAM NR CAYBY, P.R. (LAT 18°04'39"N LONG 066°06'19"W) JDL 1991 09... <0.010 <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 <0.01 LAGO LA PLATA NO.3 NR DAM NR NARANJITO, PR (LAT 18°20'18"N LONG 066°14'01"W) JDL 1991 10... <0.010 <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 <0.01 RIO QRANDB DE LOIZA BASIN—Continued LAGO LOIZA NO.7 NR DAM NR TRDJILLO ALTO, PR (LAT 18°19'29"N LONG 066°00'47"W) <0.010 <0.01 <0.010 <0.010 <0.010 <0.01 <0.01 <0.01 <0.01 425 PESTICIDE ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER-QUALITY DATA, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 NAPH- THA- LENES, PARA- POLY- PER- TOX- TOTAL THION, CHLOR. THANE APHBNB, TRI- 2,4-D, 2,4,5-T 2, 4-DP SILVBX, DATE TOTAL TOTAL TOTAL TOTAL THION TOTAL TOTAL TOTAL TOTAL (UG/L) (OO/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) 50010790 JUL 1991 12... 50039950 JUL 1991 09... 50044950 JUL 1991 10... 50058800 JUL 1991 15... RIO QUAJATACA BASIN—Continued LAOO QUAJATACA NO.1 NR DAM NR QOEBRADILLAS,PR (LAT 18°23'56"N LONG 066°55'23"W) <0.01 <0.10 <0.1 <1 <0.01 0.01 <0.01 <0.01 <0.01 RIO DE LA PLATA BASIN—Continued LAOO CARITB NO.l NR DAM NR CAYEY, P.R. (LAT 18°04'39"N LONG 066°06'19"W) <0.01 <0.10 <0.1 <1 <0.01 <0.01 <0.01 <0.01 <0.01 LAOO LA PLATA NO.3 NR DAM NR NARANJITO, PR (LAT 18°20'18"N LONG 066°14'01"W) <0.01 <0.10 <0.1 <1 <0.01 0.03 <0.01 <0.01 <0.01 RIO GRANDB DE LOIZA BASIN—Continued LAOO LOIZA NO.7 NR DAM NR TRUJILLO ALTO, PR (LAT 18°19'29"N LONG 066°00'47"W) <0.01 <0.10 <1 <0.01 0.03 <0.01 <0.01 <0.01 426 THIS PAGE WAS LEFT BLANK INTENTIONALLY 427 Ground-Water Records Puerto Rico 428 aROUND-WATBR LEVELS RIO OUAJATACA BASIN 182422067015100. Local number, 165. LOCATION.—Lat 18°24'22 > , long 67°01'51'. Owneri P.R. Aqueduct and Sewer Authority. Namei Salto• * 1 (Mateo Perez). AQUIFER.—cibao Formation. Aguada Limeatone. WELL CHARACTERISTICS.—Drilled production water-table well, diameter 16 in (0.40 m), cased 16 in (0.40 m) 0-40 ft (0-12.2 m), cased 12 in (0.30 m) 40-200 ft (12.2-61.0 m). Depth 200 ft (61.0 m). DATUM.—Elevation of land-surface datum is 689 ft (210 m) above mean sea level. Measuring point« Hole on pump base, 0.80 ft (0.24 m) above land-surface datum. Prior to November 1985, hole on top of pump base, 1.00 ft (0.30 m) above land-surface datum. REMARKS.—Recording observation well. Formerly published as 182421067015000. PERIOD OF RECORD.—January 1982 to March 1985. November 1985 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 38.81 ft (11.8 m) below land-surface datum, Oct. 5, 7, 8, 1990; lowest water level measured, 70.60 ft (21.52 m) below land-surface datum, June 18, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 38.92 38.93 38.94 38.85 38.81 38.82 38.81 38.81 38.83 38.83 38.83 38.85 38.87 38.92 38.91 38.86 38.84 38.83 38.84 38.84 38.83 38.83 38.84 38.87 38.84 38.83 38.85 38.84 38.83 —— 38.94 38.81 NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP —— —— —— —— —— ___ —— ___ —— ___ —— —— 39.94 39.93 39.95 40.01 39.98 39.99 40.01 39.93 40.00 39.98 39.90 39.86 39.84 39.82 39.82 39.81 39.80 39.82 39.88 39.87 39.86 39.85 39.87 39.96 39.99 39.97 39.96 39.96 39.94 39.95 39.91 39.94 39.87 39.86 39.95 40.01 —— 40.01 39.80 40.01 39.92 39.85 39.83 39.85 39.85 39.85 39.85 39.86 39.84 39.89 39.91 39.89 39.86 39.88 39.88 39.87 39.87 39.84 39.87 39.92 39.97 39.88 39.83 39.84 39.85 39.88 39.84 39.83 39.93 39.95 40.01 39.83 39.85 39.81 39.83 39.87 39.89 39.83 39.82 39.86 39.86 39.83 39.83 39.83 39.82 39.81 39.83 39.86 39.80 39.80 39.81 39.80 39.82 39.84 39.90 39.84 39.83 39.82 39.83 39.83 39.82 —— 39.90 39.80 39.80 39.78 39.75 39.78 39.81 39.87 39.83 39.82 39.80 39.81 39.79 39.78 39.79 39.78 39.78 39.75 39.75 39.76 39.74 39.72 39.72 39.74 39.76 39.73 39.76 39.73 39.74 39.71 39.64 39.60 39.65 39.87 39.60 39.66 39.70 39.70 39.67 39.64 39.67 39.72 39.73 39.71 39.68 39.68 39.68 39.70 39.73 39.71 39.71 39.73 39.74 39.72 39.70 39.67 39.68 39.72 39.73 39.69 39.68 39.72 39.70 39.64 39.65 —— 39.74 39.64 39.70 39.73 39.72 39.69 39.66 39.70 39.69 39.66 39.67 39.70 39.66 39.66 39.65 39.70 39.69 39.75 39.66 39.65 39.65 39.76 39.69 39.70 39.65 39.63 39.69 39.70 39.59 39.57 39.55 39.57 39.60 39.76 39.55 39.58 39.63 39.61 39.60 39.59 39.66 39.64 39.57 39.57 39.63 39.65 39.62 39.59 39.60 39.57 39.60 39.57 39.55 39.58 39.59 39.57 39.55 39.60 39.66 39.56 39.50 39.45 39.52 39.49 39.43 39.45 39.66 39.43 39.51 39.45 39.44 39.44 39.44 39.49 39.44 39.42 39.43 39.46 39.44 39.44 39.44 39.44 39.43 39.43 39.43 39.43 39.43 39.42 39.44 39.45 39.46 39.46 39.42 39.43 39.42 39.43 39.45 39.42 —— 39.51 39.42 WATER LEYEU IN FEET BELOV LAND-SURFACE DATUM Ul *. •*. L O Ul O C -x- *~ •••#• •x» **• **• **• — • ««*• »*• «••• _•- -w r*** ^jf* ~-i -f •Bllll K^ = •MM^ «M* ONDJ FMAMJJ ASONDJ FMAMJJ ASONDJ FMAMJJ AS 429 GROUND-HATER LEVELS RIO OUAJATACA BASIN 182647066552400. Local number, 202. LOCATION.—Lat 18°26'47>, long 66°55'24 I> . Owners P.R. Aqueduct and Sewer Authority. Names Canoelo Barreto Oarcia well. AQUIFER.—Aguada Linestone. WELL CHARACTERISTICS.—Drilled water-table well, diameter 20 in (0.51 m), cased 20 in (0.51 m) 0-296 ft (0-90.2 m), diameter 13 in (0.33 m), cased 13 in (0.33 m) 0-550 ft (0-167.6 m), perforated 270-529 ft (82.3-161.2 m) . Depth 550 ft (167.6 m). DATUM.—Elevation of land-surface datum is about 475 ft (145 m) above mean sea level, from topographic map. Measuring points Hole on aide of casing, 1.50 ft (0.46 m) above land-surface datum. Prior July 25, 1986, top of shelter floor, 3.30 ft (1.00 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD or RBCORD.—November 1985 to current year. EXTREMES FOR PERIOD OF RBCORD.--Highest water level recorded, 409.17 ft (124.71 m) below land-surface datum, Sept. 25, 1986; lowest water level recorded, 452.80 ft (138.01 m) below land-surface datum, June 26, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 439.22 439.17 439.12 439.07 439.41 439.43 439.48 439.50 439.57 439.62 439.60 439.61 439.57 439.52 439.41 439.26 439.15 439.01 438.86 438.66 438.45 438.20 437.96 437.68 437.43 NOV 435.63 435.42 435.19 434.95 434.77 434.37 434.17 433.95 433.74 433.50 433.27 433.05 432.84 432.66 432.46 432.27 432.05 431.95 431.81 431.65 431.51 431.40 431.27 431.20 431.12 DEC 430.65 430.57 430.56 430.52 430.45 430.42 430.39 430.36 430.33 430.29 430.28 430.29 430.25 430.25 430.24 430.23 430.16 430.13 430.15 430.15 430.10 430.07 430.04 430.05 430.07 JAN 430.11 430.09 430.10 430.11 430.12 430.11 430.10 430.10 430.12 430.13 430.14 430.15 430.17 430.22 430.25 430.27 430.29 430.35 430.37 430.37 430.40 430.46 430.52 430.55 430.55 FEB 430.86 430.87 430.88 430.92 430.95 430.99 431.03 431.06 431.10 431.17 431.22 431.26 431.27 431.31 431.40 431.47 431.51 431.55 431.59 431.65 431.67 431.71 431.72 431.79 431.80 437.17 436.89 436.62 436.36 436.13 435.89 431.01 430.93 430.85 430.78 430.69 430.07 430.08 430.08 430.09 430.10 430.10 430.58 430.60 430.65 430.71 430.72 430.80 431.85 431.92 431.96 MAR 432.01 432.02 432.07 432.11 432.16 432.21 432.27 432.30 432.35 432.41 432.52 432.57 432.60 432.64 432.72 432.76 432.82 432.89 432.87 432.95 433.02 433.07 433.10 433.13 433.18 APR MAY 439.62 435.89 435.63 430.69 430.65 430.04 430.80 430.09 431.96 430.86 433.18 432.01 434.03 434.08 434.12 434.16 434.19 434.24 434.12 434.12 434.06 433.82 433.68 433.39 434.24 433.39 433.36 433.36 433.36 433.36 JUN 433.34 433.36 433.35 433.34 433.36 433.38 433.41 433.46 433.46 433.50 433.54 433.58 433.61 433.66 433.72 433.76 433.82 433.87 433.92 433.97 434.00 434.05 434.12 434.14 434.18 JUL 434.48 434.52 434.56 434.60 434.65 434.71 434.76 434.81 434.86 434.91 434.94 434.99 435.04 435.10 435.15 435.26 435.24 435.30 435.35 435.44 435.45 435.50 435.54 435.59 435.65 AUG 436.00 436.07 436.10 436.15 436.20 436.28 436.32 436.36 436.42 436.49 436.53 436.59 436.62 436.69 436.74 436.79 436.85 436.90 436.95 437.00 437.04 437.18 437.19 437.23 437.24 SEP 437.49 437.51 437.53 437.57 437.61 437.63 437.66 437.68 437.72 437.75 437.77 437.83 437.86 437.89 437.93 437.99 438.03 438.08 438.12 438.17 438.21 438.27 438.32 438.36 438.39 434.22 434.27 434.31 434.37 434.42 —— 435.72 435.75 435.79 435.84 435.90 435.95 437.28 437.31 437.37 437.40 437.41 437.45 438.45 438.50 438.55 438.59 438.59 434.42 433.34 435.95 434.48 437.45 436.00 438.59 437.49 4i5 - 435 455 —• *-~ ^, ^> •v •-^ ^>, •s. M*^ S *•»• *^» >*» •»»• — . /• -». ^*-Jf ^«, •»•» ^ ->.. -•S, *•••« ONDJFMAMJJ ASONDJ FMAMJJ ASONDJ FMAMJJ AS 1988 1989 1990 1991 430 GROUND-WATER LEVELS RIO QRANDB DE ARBCIBO BASIN 182737066370900. Local number, 204. LOCATION.—Lat 18«27'37", long 66«37'09". Owneri Sucesi6n Marques. Namei Oilberto Rlvera well. AQUIFER.--Aymamon Limestone. NELL CHARACTERISTICS.--Abandoned unused water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). DATUM.--Elevation of land-surface datum is 48.0 ft (14.63 m) above mean sea level. Measuring pointi Air hole on pump base, 0.50 ft (0.15 m) above land-surface datum. RBHARKS.—Recording observation well. PERIOD OF RECORD.—October 1985 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 50.00 ft (15.24 m) below land-surface datum. May 14, 1986; lowest water level recorded, 52.52 ft (16.0 m) below land-surface datum, June 9, 10, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 52.09 52.03 51.99 51.91 51.88 51.87 51.86 51.87 51.91 51.91 51.91 51.94 51.92 51.89 51.86 51.81 51.76 51.61 51.51 51.46 51.52 51.51 51.54 51.54 51.61 51.62 51.61 51.61 51.58 51.56 51.56 52.09 51.46 51.56 51.54 51.55 51.58 51.63 51.69 51.77 51.80 51.85 51.87 51.85 51.80 51.79 51.77 51.77 51.79 51.76 51.74 51.72 51.76 51.77 51.79 51.82 51.84 51.86 51.89 51.91 51.86 51.79 51.77 51.91 51.54 51.76 51.79 51.75 51.76 51.78 51.77 51.78 51.79 51.82 51.84 51.86 51.85 51.88 51.87 51.89 51.91 51.96 51.94 51.93 51.95 51.95 51.94 51.91 51.87 51.85 51.87 51.89 51.91 51.92 51.93 51.92 51.96 51.75 51.88 51.88 51.90 51.92 51.92 51.96 51.97 51.96 51.97 52.00 52.00 52.00 51.99 51.99 52.02 52.03 52.02 52.04 52.04 51.99 51.97 51.92 51.91 51.98 51.99 51.98 51.99 51.96 51.99 51.98 51.99 52.04 51.88 51.99 51.98 52.00 52.00 51.99 51.99 51.99 52.02 52.03 52.01 51.99 52.01 52.05 52.06 52.01 52.00 52.05 52.06 52.08 51.99 51.96 51.99 51.98 51.95 51.94 51.94 51.93 51.93 —— 52.08 51.93 51.97 52.00 52.05 52.00 52.00 52.02 52.04 52.05 52.04 52.00 51.95 51.96 52.00 52.01 52.02 51.99 52.03 52.05 52.05 52.02 52.01 52.06 52.13 52.18 52.15 52.05 52.01 52.04 52.08 52.09 52.14 52.18 51.95 52.17 52.17 52.17 52.16 52.21 52.25 52.25 52.25 52.26 52.25 52.21 52.15 52.13 52.16 52.15 52.11 52.15 52.16 52.16 52.16 52.15 52.15 52.16 52.17 52.17 52.16 52.17 52.14 52.16 52.16 —— 52.26 52.11 52.16 52.18 52.19 52.15 52.15 52.16 52.19 52.22 52.22 52.23 52.23 52.21 52.19 52.16 52.12 52.11 52.11 52.11 52.11 52.12 52.11 52.10 52.09 52.11 52.13 52.09 52.07 52.05 52.05 51.99 51.95 52.23 51.95 51.95 51.91 51.87 51.87 51.88 51.89 51.90 51.95 52.00 52.03 52.02 52.00 51.97 51.95 51.93 51.93 51.96 52.00 52.00 52.04 52.08 52.09 52.11 52.13 52.16 52.11 52.06 52.05 52.04 52.05 —— 52.16 51.87 52.04 52.04 52.11 52.08 52.09 52.11 52.17 52.22 52.26 52.29 52.27 52.21 52.12 52.07 52.05 52.06 52.03 52.08 52.13 52.20 52.23 52.22 52.21 52.19 52.19 52.18 52.14 52.12 52.10 52.10 52.11 52.29 52.03 52.13 52.19 52.24 52.28 52.29 52.31 52.33 52.30 52.23 52.17 52.11 52.11 52.14 52.14 52.16 52.19 52.23 52.25 52.28 52.27 52.25 52.20 52.11 52.08 52.05 52.05 52.03 52.03 52.01 52.02 52.05 52.33 52.01 52.07 52.06 52.06 52.06 52.02 51.97 51.93 51.89 51.86 51.89 51.92 51.93 51.95 51.96 51.97 51.98 51.99 51.97 51.94 51.91 51.88 51.87 51.85 51.81 51.80 51.81 51.84 51.86 51.92 51.95 —— 52.07 51.80 WTR YR 1991 MEAN 51.99 LOW 52.33 BTQH 51.46 UJO 5i< df o|! 51 52 53 A* v j»*f* \ K. w A* \A/ 4 \\\ U *V f ^\ V JV -*/ **\ i> /^ V\i\ S/-r s LAv ^ *S rm/ ONDJFMAMJJASONDJFMAMJJASONDJFMAMJJAS 1988 1989 1990 1991 434 GROUND-WATER LEVELS RIO ORANDB DE MANATI BASIN 182308066260400. Local number, 210. LOCATION.—Lat 18°23'08", long 66026'04«. Ownert Oelo Martinez. Namet Oelo Martinez well. AQUIFER.--Lares Linestone. WELL CHARACTERISTICS.—Drilled unused water-table well, diameter 8 in (0.20 m), cased 8 in (0.20 m). DATUM.--Elevation of land-surface datum is about 574 ft (174.9 m) above mean sea level, from topographic map. Measuring pointt Hole on side of casing, 2.00 ft (0.61 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.--October 1985 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 40.56 ft (12.36 m) below land-surface datum. May 22, 1986; lowest water level recorded, 78.61 ft (24.0 m) below land-surface datum, Sept. 12, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL ADO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HI OH 76.61 76.62 76.62 76.62 76.58 76.55 76.53 76.51 76.50 76.47 76.37 76.30 76.24 76.11 75.88 75.45 74.68 71.48 --- —— ___ —— 76.62 71.48 —— —— ___ —— ___ —— ___ ___ —— 70.46 —— 70.46 70.46 —— —— ___ —— 65.64 —— ___ ___ 66.71 66.97 67.28 67.68 68.07 68.39 68.70 68.88 69.03 69.20 69.41 69.63 69.84 69.84 65.64 69.93 69.21 67.65 —— 67.46 67.71 67.96 68.17 68.38 68.58 68.70 68.78 68.88 68.96 69.03 69.11 69.21 69.34 69.45 69.57 69.67 69.77 69.85 69.91 69.97 70.04 70.04 67.46 70.11 70.16 70.23 70.28 70.34 70.40 70.47 70.55 70.65 70.71 70.72 70.89 70.97 71.03 71.11 71.21 71.29 71.35 71.37 71.27 69.76 67.40 67.39 67.39 67.39 67.39 67.39 67.39 —— 71.37 67.39 67.39 67.39 67.39 67.39 67.70 68.10 68.66 68.90 69.10 69.32 69.66 69.92 70.25 70.45 70.64 70.84 70.93 71.11 71.28 71.33 71.48 71.62 71.66 71.70 71.83 71.86 71.92 72.06 72.07 72.22 72.25 74.14 67.39 72.30 72.30 72.48 72.51 72.62 72.67 72.70 72.83 72.88 72.91 73.02 73.07 73.09 73.11 73.22 73.27 73.29 73.40 73.42 73.46 73.49 73.60 73.63 73.66 73.69 73.79 73.85 73.91 73.97 74.04 —— 74.04 72.30 74.10 74.16 74.19 74.24 74.27 74.34 74.38 74.41 74.45 74.47 74.50 74.53 74.55 74.58 74.59 74.59 74.60 74.60 74.65 74.66 74.67 74.68 74.70 74.71 74.74 74.76 74.80 74.82 74.84 74.85 74.90 74.90 74.10 74.93 74.96 74.97 75.00 75.02 75.06 75.09 75.13 75.17 75.21 75.22 75.24 75.26 75.28 75.30 75.34 75.37 75.41 75.44 75.45 75.51 75.54 75.56 75.59 75.64 75.68 75.73 75.78 75.82 75.86 —— 75.86 74.93 75.92 75.96 75.96 75.99 76.04 76.07 76.13 76.17 76.21 76.25 76.29 76.34 76.39 76.45 76.49 76.53 76.54 76.56 76.57 76.60 76.62 76.66 76.69 76.73 76.77 76.82 76.85 76.88 76.91 76.95 76.99 76.99 75.92 77.02 77.06 77.09 77.13 77.17 77.23 77.28 77.34 77.38 77.42 77.46 77.50 77.55 77.59 77.65 77.69 77.73 77.77 77.81 77.84 77.89 77.95 77.98 78.04 78.09 78.13 78.16 78.18 78.20 78.24 78.24 78.24 77.02 78.27 78.30 78.33 78.36 78.39 78.43 78.47 78.51 78.54 78.56 78.58 78.61 78.51 78.43 78.36 78.33 78.29 78.27 78.25 78.25 78.24 78.23 78.23 78.23 78.23 78.23 78.23 78.24 78.25 78.27 —— 78.61 78.23 40 60 80 ONDJFMAMJJ 1988 1989 ASONDJ F M A M J J 1990 ASONDJ FMAMJJ 1991 A S 435 GROUND-WATER LEVELS RIO CIBUCO BASIN 182647066201700. Local number, 70. LOCATION.—Lat 18°26'47-, long 66°20'17". Owneri P.R. Aqueduct and Sewer Authority. Name i Sabana Hoyos. AQUIFER.—Limestone of Tertiary Age. NELL CHARACTERISTICS.—Drilled unused artesian well, diameter 8 in (0.20 m), cased 0-90 ft (0-27.43 m), perforated. Depth 90 ft (27.43 m). DATUM.—Elevation of land-surface datum is about 49 ft (14.9 m) above mean sea level, from topographic map. Measuring pointi Top of caving wooden cover, 1.30 ft (0.40 m) above land-surface datum. REHARKS.—Recording observation well. PERIOD OF RECORD.—February 1960 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 21.33 ft (6.50 m) below land-surface datum, Oct. 26, 1976; lowest water level recorded, 31.10 ft (9.48 m) below land-surface datum, July 31, 1975. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANMTANBOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 29.45 29.46 —— —— —— —— —— 29.43 29.42 29.39 29.37 29.35 29.33 29.32 29.29 29.26 29.21 29.02 28.87 28.72 28.56 28.43 28.33 28.25 28.19 28.14 28.09 28.06 28.05 28.04 29.46 28.04 28.04 28.05 28.06 28.08 28.10 28.13 28.16 28.19 28.23 28.26 28.30 28.33 28.36 —— 28.46 28.48 28.50 28.53 28.55 28.53 28.51 28.51 28.51 28.52 28.53 28.54 28.54 28.53 28.53 28.51 —— 28.55 28.04 28.51 28.50 28.47 28.42 28.38 28.34 28.32 28.30 28.30 28.30 28.30 28.31 28.30 28.30 28.30 28.31 28.31 28.32 28.33 28.34 28.36 28.37 28.38 28.38 28.39 28.41 28.42 28.43 28.44 28.44 28.43 28.51 28.30 28.40 28.37 28.33 28.31 28.28 28.25 28.22 28.18 28.16 28.12 28.09 28.07 28.06 28.04 28.04 28.04 28.04 28.05 28.06 28.07 28.08 28.10 28.12 28.16 28.18 28.21 28.23 28.26 28.29 28.31 28.33 28.40 28.04 28.35 28.37 28.39 28.41 28.42 28.44 28.44 28.45 28.46 28.48 28.50 28.49 28.50 28.50 28.51 28.51 28.52 28.54 28.29 28.00 27.80 27.66 27.56 27.48 27.42 27.39 27.36 27.36 —— —— —— 28.54 27.36 27.24 27.24 27.22 27.24 27.26 27.28 27.33 27.37 27.41 27.46 27.50 27.54 27.58 27.61 27.66 27.69 27.74 27.78 27.81 27.86 27.89 27.92 27.94 27.98 28.01 28.06 28.10 28.13 28.16 28.20 28.24 28.24 27.22 28.27 28.30 28.33 28.36 28.39 28.43 28.45 28.48 28.52 28.54 28.56 28.58 28.59 28.61 28.63 28.44 28.44 28.44 28.43 28.43 28.43 28.44 28.46 28.48 28.50 28.52 28.54 28.56 28.58 28.59 —— 28.63 28.27 28.61 28.64 28.67 28.68 28.70 28.71 28.71 28.73 28.74 28.75 28.76 28.77 28.78 28.80 28.81 28.82 28.84 28.84 28.85 28.86 28.87 28.88 28.89 28.90 28.91 28.91 28.91 28.91 28.91 28.92 28.92 28.92 28.61 28.92 28.93 28.93 28.94 28.95 28.96 28.97 28.98 28.99 29.00 29.01 29.03 29.04 29.06 29.08 29.09 29.10 29.12 29.13 29.14 29.15 29.16 29.17 29.18 29.20 29.22 29.23* 29.24 29.26 29.27 —— 29.27 28.92 29.27 29.29 29.31 29.32 29.34 29.35 29.36 29.37 29.39 29.41 29.43 29.45 29.47 29.49 29.50 29.46 29.44 29.41 29.39 29.39 29.39 29.40 29.42 29.44 29.45 29.46 29.47 29.48 29.48 29.49 29.49 29.50 29.27 29.50 29.51 29.52 29.53 29.54 29.56 29.57 29.58 29.60 29.60 29.60 29.61 29.62 29.63 29.64 29.65 29.65 29.66 29.66 29.67 29.67 29.67 29.65 29.65 29.65 29.66 29.66 29.65 29.64 29.63 29.59 29.67 29.50 29.57 29.58 29.58 29.59 29.59 29.60 29.60 29.60 29.59 29.60 29.60 29.61 29.61 29.64 29.66 29.67 29.67 29.67 29.67 29.66 29.66 29.63 29.62 29.61 29.60 29.60 29.60 29.59 29.59 29.59 —— 29.67 29.57 24 28 32 •***" X «r- \x- V *"> X. •«••, •^xyJ X, s /" X •^> ~v •--r ^-» •-> J J\ >*r> ***. "^ •v* ONDJFMAMJJASONDJFMAMJJASONDJFMAMJJAS 1988 1989 1990 1991 436 GROUND-WATER LEVELS RIO CIBUCO BASIN 182615066235300. Local number, 211. LOCATION.—Lat 18»26'15", long 66»23'53". Owneri P.R. Aqueduct and Sewer Authority. Name i Rosario No. 2. AQUIFER.—Aguada Limestone. WELL CHARACTERISTICS.—Drilled unused water-table well, diameter 14 in (0.36 m) (0.30 m) 200-250 ft (61.0-76.2 m), cased 12 in (0.30 m) 0-250 ft (0-76.2 m) 0-200 ft (0-61.0 m), diameter 12 in perforated 210-250 ft (64.0-76.2 m), diameter 10 in (0.25 m) 250-270 ft (76.2-82.3 m), open hole; concrete sealed 0-200 ft (0-61.0 »). Depth 270 ft (82.3 m). DATUM.—Elevation of land-surface datum i« about 215 ft (65.5 m) above mean sea level, from topographic map. Measuring points Hole on side of casing, 1.15 ft (0.35 m) above land-surface datum. REHARKS.--Recording observation well. PERIOD OF RECORD.—October 1985 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 191.29 ft (58.30 m) below land-surface datum, May 16, 1986; lowest water level recorded, 193.63 ft (59.02 m) below land-surface datum, July 21-25, 1990 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 OCT 193.47 193.47 193.47 193.47 193.46 193.44 193.41 193.38 193.38 193.37 193.22 193.22 193.22 193.21 193.18 193.18 193.08 192.95 192.87 192.77 192.72 192.70 192.67 192.67 192.67 NOV 192.67 192.67 192.71 192.73 192.75 192.80 192.83 192.85 192.87 192.89 192.91 192.92 192.94 192.94 192.94 192.95 192.95 192.95 192.95 192.93 192.91 192.89 192.89 192.89 192.89 DEC 192.88 192.87 192.87 192.84 192.79 192.78 192.78 192.78 192.78 192.78 192.78 192.78 192.78 192.79 192.82 192.85 192.90 192.95 192.95 192.95 192.95 192.95 192.95 192.95 192.95 JAN 192.94 192.90 192.87 192.87 192.87 192.87 192.87 192.87 192.87 192.87 192.87 192.83 192.83 192.83 192.83 192.83 192.83 192.82 192.82 192.84 FBB 192.86 192.86 192.86 192.85 192.87 192.87 192.87 192.87 192.91 192.93 192.93 192.92 192.92 192.92 192.92 192.91 192.91 192.91 192.81 192.63 192.47 192.46 192.46 192.46 192.45 MAR 192.46 192.46 192.46 192.46 192.52 192.54 192.57 192.59 192.58 192.59 192.59 192.59 192.59 192.60 192.61 192.61 192.60 192.63 192.64 192.66 192.65 192.68 192.68 192.71 192.73 APR 192.86 192.88 192.88 192.90 192.92 192.94 192.95 192.96 193.02 193.03 193.04 193.05 193.05 193.06 193.07 193.08 193.04 193.04 193.05 193.06 193.07 193.08 193.07 193.08 193.09 HAY 193.13 193.13 193.14 193.13 193.13 193.13 193.13 193.13 193.13 193.13 193.13 193.13 193.13 193.13 193.13 193.13 193.13 193.13 193.14 193.14 193.14 193.14 193.14 193.14 193.14 26 27 28 29 30 31 192.67 192 . 67 192.67 192 . 67 192 . 67 192.67 192.89 192.89 192.89 192.89 192.89 —— 192.95 192.95 192.95 192 . 95 192.95 192.95 192.85 192.85 192.85 192.86 192.86 192.86 192.45 192.47 192.47 —— 192.74 192.74 192.75 192.75 192.77 192.80 193 . 10 193 . 11 193.12 193 . 14 193.15 —— 193.14 193 . 14 193 . 14 193 . 14 193 . 14 193.14 JUN 193.14 193.14 193.12 LOW HIGH 193.47 192.67 192.95 192.67 192.95 192.78 192.94 192.82 192.93 192.45 192.80 192.46 193.15 192.86 193.14 193.13 193.14 193.12 JUL 193.24 193.24 193.24 193.26 193.27 193.30 193.34 193.35 193.36 193.36 193.37 193.37 193.38 193.35 193.34 193.31 193.31 193.31 193.31 193.31 193.31 193.31 193.31 193.31 193.31 193.31 193.31 193.31 193.38 193.24 AUG 193.31 193.31 193.35 193.35 193.35 193.36 193.37 193.37 193.41 193.42 193.42 193.42 193.42 193.42 193.42 193.42 193.42 193.42 193.42 193.42 193.42 193.42 193.44 193.43 193.43 193.42 193.42 193.42 193.42 193.40 193.39 193.44 193.31 SEP 193.39 193.38 193.37 193.37 193.37 193.36 193.36 193.35 193.29 193.27 193.27 193.27 193.27 193.28 193.28 193.28 193.28 193.28 193.28 193.29 193.29 193.29 193.29 193.29 193.29 193.28 193.26 193.26 193.26 193.26 193.39 193.26 "1 190 -£ 192 194 -J^ ONDJ FMAMJ J ASONDJ FMAMJJ ASONDJ FMAMJJ AS 1988 1989 1990 1991 GRODNO-WATER LEVELS RIO CIBUCO BASIN 437 182515066194000. Local number, 212. LOCATION.—Lat 18«25'15-, long 66°19'40-. Owner» U.S. Geological Survey. Namei Ponderoia TW-1. AQUIFER.—Aguada Linestone-Clbao Formation. NELL CHARACTERISTICS.—Drilled unused water-table well, diameter 4 in (0.10 m), cased 4 in (0.10 m) 0-136 ft (0-41.1 m), perforated 121-131 ft (36.9-39.9 m); bentonite packed 0.5-121 ft (0.15-36.9 m). Depth 136 ft (39.9 m). DATUM.—Elevation of land-surface datum is about 98.0 ft (29.9 m) above mean sea level, from topographic map. Measuring pointt Shelter floor on top of 4 in (0.10 m) casing, 3.00 ft (0.91 m) above land-surface datum. REMARKS.—Recording observation well. Water levels affected by nearby pumping well. PERIOD OF RECORD.—October 1985 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 63.05 ft (19.22 m) below land-surface datum, July 15, 1987; lowest water level recorded, 74.63 ft (22.75 m) below land-surface datum, Oct. 27,28, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HI OH OCT 70.27 70.29 70.32 70.32 70.31 70.29 70.27 70.26 70.25 70.25 70.26 70.25 70.22 70.20 70.18 70.18 70.16 70.10 69.91 69.70 69.54 69.40 68.89 68.84 68.77 68.69 68.64 68.56 70.32 68.56 NOV 68.48 68.44 68.42 68.41 68.35 68.33 68.32 68.32 68.32 68.33 68.33 68.34 68.37 68.39 68.41 68.42 68.44 68.45 68.49 68.53 68.54 68.54 68.56 68.57 68.59 68.60 68.60 68.56 68.55 68.53 68.60 68.32 DEC 68.49 68.46 68.45 68.28 68.14 68.05 68.01 67.99 67.97 67.95 67.94 67.95 67.95 67.95 67.96 67.97 67.97 67.98 68.00 68.02 68.03 68.04 68.05 68.08 68.12 68.14 68.17 68.18 68.21 68.22 68.22 68.49 67.94 JAN 68.13 68.02 67.97 67.94 67.90 67.88 67.82 67.80 67.77 67.74 67.71 67.67 67.64 67.62 67.60 67.59 67.58 67.58 67.58 67.58 67.58 67.61 67.69 67.68 67.68 67.69 67.71 67.72 67.72 67.72 67.75 68.13 67.58 FEB 67.78 67.80 67.82 67.84 67.87 67.91 67.93 MAR APR 66.99 67.93 67.78 67.54 67.56 67.55 67.53 67.52 67.53 67.53 67.53 67.54 67.57 67.59 67.61 67.63 67.66 67.71 67.71 66.99 MAY 67.69 67.73 67.73 67.77 67.78 67.82 67.83 67.85 67.85 67.87 67.87 67.88 67.89 67.91 67.94 67.95 67.97 67.98 67.99 68.00 68.01 68.02 68.06 68.07 68.15 68.16 68.16 68.14 68.11 68.12 68.13 68.16 67.69 JUN 68.15 68.16 68.17 68.19 68.22 68.25 68.27 68.28 68.29 68.40 68.42 68.43 68.45 68.51 68.53 68.56 68.59 68.62 68.64 68.66 68.68 68.71 68.75 68.78 68.79 68.81 68.83 68.86 68.88 68.89 68.89 68.15 JUL 68.90 68.93 68.96 68.98 69.00 69.01 69.03 69.09 69.10 69.17 69.16 69.18 69.19 69.19 69.21 69.22 69.18 69.15 69.13 69.13 69.12 69.11 69.11 69.10 69.11 69.11 69.10 69.11 69.11 69.10 69.12 69.22 68.90 AUG 69.11 69.16 69.16 69.17 69.18 69.18 69.18 69.20 69.21 69.25 69.27 69.27 69.29 69.30 69.32 69.34 69.35 69.37 69.38 69.39 69.44 69.45 69.46 69.48 69.49 69.50 69.54 69.54 69.54 69.55 69.56 69.56 69.11 SEP 69.58 69.59 69.60 69.62 69.62 69.64 69.66 69.66 69.67 69.69 69.69 69.70 69.72 69.74 69.77 69.78 69.80 69.82 69.83 69.85 69.87 69.88 69.88 69.90 69.91 69.92 69.93 69.93 69.95 69.95 69.95 69.58 60 65 70 ONDJFMAMJJ 1988 1989 ASONDJFM 1990 AMJJASON DJFMAMJJ 1991 A S 438 GROUND-WATER LEVELS RIO CIBDCO BASIN 182330066185700. Local number, 213. LOCATION.--Lat 18»23'30", long 66«18'57". Ownert P.R. Aqueduct and Sewer Authority. Names Pampano No. 2. AQUIFER.—Rio Indio Limestone-Lares Limestone. WELL CHARACTERISTICS.—Drilled unused water-table well, diameter 20 in (0.51 m), cased 20 in (0.51 m) 0-130 ft (0-39.6 m), diameter 14 in (0.36 m), cased 12 in (0.30 m) 0-220 ft (0-67.1 m)> open hole 220-330 ft (67.6- 100.6 m). Depth 330 ft (100.6 m). DATUM.—Elevation of land-surface datum is about 394 ft (120 m) above mean sea level, from topographic map. measuring pointi Hole on side of casing, 2.95 ft (0.90 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—October 1985 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 34.40 ft (10.50 m) below land-surface datum, Dec. 6, 1985) lowest water level recorded, 56.53 ft (17.2 m) below land-surface datum, Sept. 30, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HI OH OCT 54.99 55.08 55.11 55.08 55.01 55.10 55.06 55.04 55.02 55.10 55.03 55.00 54.98 54.99 54.96 54.92 54.87 54.72 54.42 54.18 53.94 53.57 53.22 53.00 52.79 52.55 52.33 52.09 51.90 51.76 51.61 55.11 51.61 NOV 51.55 51.35 51.24 51.13 51.06 51.03 51.00 50.98 51.01 51.06 51.03 51.11 51.12 51.14 51.14 51.15 51.16 51.25 51.32 51.31 51.31 51.34 51.41 51.44 51.47 51.51 51.53 51.51 51.49 51.49 51.55 50.98 DEC JAN 51.50 51.44 51.41 51.11 50.78 50.57 50.41 50.31 50.19 50.10 50.04 50.01 49.95 49.91 49.84 49.84 49.75 49.69 49.71 49.71 49.70 49.67 49.62 49.64 49.70 49.70 49.69 49.71 49.74 49.74 49.70 51.50 49.62 49.43 49.08 48.79 48.56 48.40 48.25 47.99 47.83 47.68 47.63 47.48 47.37 47.27 47.24 47.19 47.17 47.10 47.10 47.08 47.01 47.04 47.04 47.05 47.08 47.08 47.11 47.16 47.16 47.23 47.22 47.23 49.43 47.01 FBB 47.32 47.29 47.30 47.33 47.31 47.30 47.30 47.21 47.11 47.05 47.04 46.95 46.91 46.84 46.85 46.85 46.83 46.80 46.29 46.03 45.89 45.64 45.46 45.Jl 45.15 45.01 44.98 44.93 47.33 44.93 MAR 44.89 44.83 44.78 44.72 44.69 44.70 44.69 44.67 44.69 44.68 44.64 44.85 44.88 44.89 44.97 45.01 45.11 45.09 45.08 45.12 45.18 45.26 45.38 45.45 45.48 45.59 45.47 45.48 45.47 45.77 45.89 45.89 44.64 APR 45.80 45.85 45.92 45.95 45.97 46.04 46.11 46.20 46.28 46.30 46.38 46.42 46.50 46.52 46.63 46.69 46.72 46.81 46.84 46.94 46.96 47.07 47.10 47.33 47.36 47.46 47.54 47.65 47.71 47.83 47.83 45.80 MAY 47.83 47.92 47.94 48.10 48.22 48.24 48.33 48.13 48.42 48.61 48.69 48.80 48.90 48.98 49.05 49.10 49.22 49.29 49.40 49.42 49.46 49.52 49.55 49.64 49.70 49.65 49.68 49.68 49.71 49.72 49.72 49.72 47.83 JUN 49.77 49.81 49.87 49.92 49.94 50.07 50.13 50.24 50.28 50.42 50.51 50.65 50.75 50.83 50.87 50.92 50.99 50.98 51.05 51.08 51.01 51.14 51.18 51.28 51.38 51.46 51.55 51.57 51.58 51.63 51.63 49.77 JUL 51.64 51.78 51.79 51.87 51.92 52.03 52.11 52.15 52.26 52.36 52.41 52.49 52.62 52.66 52.74 52.75 52.75 52.69 52.67 52.75 52.73 52.72 52.73 52.76 52.83 52.86 52.92 52.95 53.00 53.04 53.19 53.19 51.64 AUQ 53.25 53.33 53.36 53.32 53.37 53.41 53.47 53.51 53.60 53.69 53.74 53.75 53.74 53.81 53.81 53.97 53.99 54.03 54.09 54.22 54.26 54.29 54.36 54.52 54.50 54.52 54.55 54.56 54.55 54.57 54.68 54.68 53.25 SEP 54.68 54.71 54.73 54.89 54.65 54.50 54.38 54.33 54.33 54.34 54.32 54.31 54.94 55.17 55.30 55.36 55.34 55.50 55.69 55.75 55.91 55.98 56.07 56.23 56.13 56.15 56.17 56.29 56.46 56.50 56.50 54.31 WTR YR 1991 MEAN 50.26 LOW 56.50 HIGH 44.64 35 X, 55 V, ^v ONDJFMAMJJASONDJFMAMJJASONDJFMAMJJAS 1988 1989 1990 1991 I IS 3 O <0 • -J M WATER LEVEL. IN FEET BELOW LAND-SURFACE DATUM MMMMM MMMMM ; M M O MM 4 P r\> J° _ IS bi o bi Jo oo MMMMM 46(6(61010 So 0°-7 OB2 O £<- s i: MMMMM MM M M M M M M MMMMM MMMMM MMMMM MMMMM MMMMM *6 *6 *0 *6 *6 *6 *6 *6 40 40 40 40 40 40 40 40 40 40 40 46 *0 *0 *6 40 40 40 40 40 40 40 46 *6 *6 M M M M M M 40 40 40 40 40 40 .. |||... ..... ..... ..... Ilk * «0 I I | «k «k «k *. *. VI VI VI UI »J«0 «0 «J «J <•! <0 «0 «0 «0*0WU11J -J -J •» h* 00 ~J 9> O O O MM MMMMMM MMMMM MMMMM MMMMM MMMMM MMMMM 40O *6*6OOOO OOOOO OOOOO O O O O O OOOOO OOOOO VOM *e*eoooo ooooo ooooo o o o o o OOMOO ooooo P MM w *k o H * vi ve «j «k u *i oe*o*em«\ «k vi ~J «e vo «o*6M*6ot WMWMM K MM MMMMMM MMMMM MMMMM MMMMM MMMMM MMMMM . . ????. . ????? ????? ????? ??. ?? . . ??? >. M*> MMMMMM MMMMW w^uiiku uwwuw u u u «k «k «k «k u u u Q OTU M*n]VI*iJ40M U(J1^40VI **JO*OOOO MUMMM MM**JUU OO*6V1M O MMMMM MMMMM MMMMM MMMMM MMMMM MMMMM '&S& " 2 * 4 P 9 *e •>] M « ui 'MMM MOOMM MMMMM CO CD 440 GROUND-WATER LEVELS RIO DE LA PLATA BASIN 182530066135400. Local number, 216. LOCATION.—Lat 18«25'30", long 66°13'54". Owners P.R. Aqueduct and Sewer Authority. Namei Pozo Navy-Campanillas. AQUIFER.—Aguada Limestone. WELL CHARACTERISTICS.—Drilled unused water-table well, diameter 16 in (0.41 m) 0-106 ft (0-32.3 m), cased 16 in (0.41 m) 0-20 ft (0-6.10 m), cased 12 in (0.30 m) 0-106 ft (0-32.3 m), perforated 20-106 ft (6.10-32.3 m), diameter 10 in (10.25 m) 106-140 ft (32.3-42.7 m), cased 10 in (0.25 m) 106-140 ft (32.3-42.7 m), perforated 106-140 ft (32.3-42.7 m). Depth 140 ft (42.7 m). DATUM.—Elevation of land-surface datum i« about 13.0 ft (3.96 m) above mean sea level, from topographic map. Measuring points Hole on side of casing, 1.80 ft (0.55 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—October 1985 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 9.38 ft (2.86 m) below land-surface datum, June 23, 1987; lowest water level recorded, 14.72 ft (4.49 m) below land-surface datum, Apr. 28, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 13.48 13.47 13.18 12.98 12.88 12.85 12.80 12.77 12.79 12.74 12.58 12.68 12.83 12.89 12.84 12.55 12.24 12.36 11.80 11.65 11.70 11.56 11.62 11.58 11.69 11.64 11.43 11.44 11.44 11.48 11.51 13.48 11.43 NOV 11.53 11.57 11.61 11.63 11.68 11.72 11.76 11.79 11.84 11.87 11.89 11.90 11.91 11.93 11.95 12.19 12.25 12.32 12.36 12.36 12.36 12.38 12.42 12.69 12.97 12.96 13.02 13.05 13.06 13.02 13.06 11.53 DEC 13.00 12.97 12.87 12.79 12.79 12.85 12.90 12.93 12.96 12.95 13.01 12.81 12.74 12.83 12.90 12.90 12.90 12.92 12.96 12.99 13.02 13.02 13.03 13.05 13.08 13.12 13.18 13.18 13.13 13.12 13.09 13.18 12.74 JAN 12.95 12.90 12.91 12.93 12.90 12.89 12.83 12.82 12.79 12.77 12.79 12.78 12.76 12.76 12.78 12.80 12.81 12.85 12.88 12.85 12.62 12.35 12.87 12.96 13.00 13.03 13.07 13.08 13.13 13.16 13.18 13.18 12.35 FBB 13.19 12.99 13.18 13.21 13.22 13.19 13.21 13.25 13.29 13.32 13.32 13.32 13.31 13.30 13.43 13.46 13.44 12.96 12.39 11.99 11.81 11.77 11.76 11.76 11.75 11.75 11.79 11.81 13.46 11.75 MAR 11.83 11.87 11.91 11.88 11.88 11.90 11.96 12.00 12.05 12.06 12.10 12.10 12.12 12.15 12.19 12.21 12.25 12.26 12.28 12.30 12.34 12.35 12.34 12.39 12.42 12.44 12.48 12.50 12.55 12.60 12.65 12.65 11.83 APR 12.67 12.70 12.70 12.74 12.76 12.78 12.81 12.83 12.85 12.86 12.86 12.86 12.85 12.86 12.87 12.56 12.50 12.51 12.51 12.52 12.53 12.56 12.60 12.63 12.65 12.64 12.66 12.67 12.69 12.71 12.87 12.50 MAY 12.71 12.75 12.64 12.52 12.72 12.72 12.75 12.77 12.64 12.71 12.73 12.76 12.78 12.79 12.81 12.71 12.83 12.79 13.12 13.10 13.08 13.08 12.74 12.94 12.91 12.87 12.86 12.84 12.42 12.35 12.41 13.12 12.35 JDN 13.04 13.12 13.17 13.23 13.28 13.33 13.38 13.44 13.49 13.53 13.57 13.61 13.66 13.69 12.90 13.48 13.61 13.68 13.68 13.68 13.70 13.66 13.69 13.70 13.87 13.90 13.56 13.78 13.90 12.90 JUL 14.09 14.13 14.17 14.18 14.18 14.17 14.19 14.21 14.21 14.09 AUQ 14.15 14.17 14.23 14.36 14.39 14.34 14.36 14.38 14.41 14.44 14.50 14.59 14.50 14.51 14.50 14.52 14.52 14.39 14.27 14.33 13.93 13.68 13.53 13.48 13.48 13.49 13.34 13.16 13.08 13.13 13.18 14.59 13.08 SEP 13.19 13.18 13.19 13.21 13.23 13.26 13.26 13.24 13.24 13.27 13.23 13.24 13.25 13.27 13.29 13.28 13.27 13.27 13.29 13.29 13.32 13.33 13.34 13.34 13.34 13.35 13.33 13.35 13.18 11 13 15 17 'M .A Js ONDJFMAMJJ 1988 1989 ASONDJFMAMJJ 1990 ASONDJFMAMJJ 1991 AS GROUND-WATER LEVELS RIO DE LA PLATA BASIN 441 182655066142400. Local number, 217. LOCATION.—Lat 18026'55", long 66°14'24". Owneri U.S. Geological Survey. Kamai Monserrate TW-2. AQUIFER.-Alluvial Deposit*. WELL CHARACTERISTICS.—Drilled unused water-table well, diameter 4 in (0.10 m), caved 4 in (0.10 m) 0-80 ft (0-24.4 m), perforated 10-80 ft (3.05-24.4 m). Depth 80 ft (24.4 m). DATUM.—Elevation of land-surface datum is about 3.30 ft (1.00 m) above mean sea level, from topographic map. measuring pointi Top of shelter floor, 3.50 ft (1.07 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—November 1985 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 0.02 ft (0.006 m) below land-surface datum. May 16, 1986; lowest water level recorded, 2.24 ft (0.68 m) below land-surface datum, Aug. 7, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 1.86 1.82 1.70 1.58 1.54 1.55 1.51 1.51 1.57 1.54 1.42 1.43 1.47 1.44 1.47 1.37 1.19 1.19 .77 .78 .64 .61 .75 .76 .85 .76 .75 .78 .77 .79 .83 1.86 .61 NOV .86 .86 L.OO L.05 L.ll 1.17 1.23 1.24 1.27 1.27 1.28 1.26 1.27 1.26 1.26 1.27 1.27 1.30 1.31 1.29 1.28 1.29 1.33 1.35 1.40 1.27 1.42 .86 DEC 1.26 1.27 1.17 1.13 1.13 1.16 1.18 1.21 1.24 1.25 1.22 1.21 1.25 1.23 1.25 1.30 1.31 1.28 1.27 1.24 1.25 1.28 1.33 1.33 1.28 1.24 1.18 1.33 1.13 JAN L.09 L.08 L.13 L.15 L.16 1.15 1.13 1.12 1.11 1.11 1.12 1.12 1.11 1.15 1.19 1.20 1.21 1.26 1.27 1.25 1.21 1.18 1.23 28 1.34 1.35 1.37 1.37 1.42 1.41 1.41 FEB 1.40 1.38 1.38 1.39 1.36 1.32 1.35 1.39 1.43 1.45 1.20 MAR ,06 .05 ,04 1.06 1.10 1.11 1.16 1.16 1.15 1.16 1.18 1.18 1.21 1.21 1.24 1.25 1.24 1.24 1.27 1.30 1.30 1.37 1.36 1.31 1.32 1.33 1.40 1.45 1.49 APR 1.48 1.37 1.41 1.44 1.47 1.48 1.50 1.51 1.51 1.49 1.48 1.45 1.43 1.46 1.45 1.25 1.27 1.28 1.28 1.33 1.33 1.37 1.43 45 1.48 ,49 ,52 ,53 54 1.42 1.08 It45 1.20 1.49 1.04 1.55 1.55 1.25 MAY 1.56 1.56 1.56 1.52 1.57 1.59 1.63 1.64 1.63 1.64 1.65 1.67 1.67 1.66 1.66 1.66 1.62 1.63 1.65 1.65 1.65 1.62 1.62 1.60 1.59 1.52 1.50 JUN 1.59 1.60 1.61 1.62 1.64 1.66 1.68 1.71 1.72 1.76 1.77 1.78 1.76 1.74 1.67 1.70 1.74 1.80 1.79 1.82 1.84 1.83 1.77 1.78 1.83 JUL 86 89 94 96 97 99 01 02 11 2.14 .11 .12 ,10 .11 .11 1.91 .70 .77 .82 1.93 1.69 1.50 1.85 1.59 1.99 2.00 1.99 1.99 1.99 1.98 1.98 2.14 1.70 AUG 1.99 2.01 2.13 2.17 2.19 2.23 2.24 2.20 17 2.17 2.19 2.19 2.19 2.20 2.18 2.23 2.24 2.17 2.18 2.18 2.16 2.02 1.91 1.93 1.91 1.91 1.85 1.69 1.66 1.66 1.71 2.24 1.66 SEP 1.72 1.73 1.74 1.77 1.76 1.74 1.71 1.70 1.69 1.71 1.69 1.70 1.68 1.69 1.66 1.62 1.64 1.65 1.65 1.60 ,62 ,62 ,59 ,57 ,55 ,58 ,62 .62 ,64 1.63 1.77 1.55 u 1 2 2.5 \ A s *•J•\*\*V «* njIV l\ s\jfNt^^ I¥ rA v\fs^ > vJ s ,A u k, ifu J s ONOJ FMAMJJ ASONOJ FMAMJJ ASONDJ FMAMJJ AS 1988 1989 1990 1991 442 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NUEVO BASINS 182623066111000. Local number, 218. LOCATION.—Lat 18«26'23", long 660 11'10". Owneri P.R. Aqueduct and Sewer Authority. Namei Levittovm No. 7. AQUIFER.—Alluvial deposits-Aymamon Limestone. NELL CHARACTERISTICS.—Drilled water-table well. DATUM.—Elevation of land surface datum is about 10.0 ft (3.05 m) above mean sea level, from topographic map. Measuring pointt Hole on pump base, 1.55 ft (0.47 m) above land-surface datum. REMARKS.--Recording observation well. Water levels affected by nearby pumping well. PERIOD OF RECORD.—October 1985 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 5.94 ft (1.81 m) below land-surface datum, Sept. 20, 1989; lowest water level recorded, 9.77 ft (2.98 m) below land-surface datum, Mar. 23, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 8.39 8.36 8.32 8.24 8.20 8.20 8.18 8.18 8.22 8.21 8.17 8.18 8.17 8.16 8.15 8.13 8.02 7.94 7.81 7.77 7.72 7.62 7.61 7.59 7.61 7.97 8.19 8.23 8.22 8.24 8.20 8.39 7.59 NOV 8.25 8.27 8.35 8.40 8.40 8.45 8.40 8.43 8.45 8.51 8.49 8.47 8.39 8.25 8.23 8.23 8.24 8.26 8.26 8.27 8.26 8.34 8.38 8.43 8.47 8.44 8.43 8.42 8.38 8.34 8.51 8.23 DEC 8.32 8.32 8.26 8.08 8.06 8.04 8.05 8.06 8.08 8.06 8.08 8.06 8.07 8.07 8.09 8.10 8.13 8.11 8.12 8.14 8.15 8.15 8.13 8.12 8.16 8.13 8.15 8.16 8.13 8.11 8.08 8.32 8.04 JAN 8.04 8.01 8.01 8.00 7.98 7.99 7.97 7.96 7.95 7.93 7.95 7.97 7.97 8.00 8.02 8.00 7.99 7.99 8.01 8.04 8.07 8.06 8.08 8.07 8.10 8.11 8.12 8.12 7.92 FEB 8.13 8.13 8.16 8.15 8.15 8.14 8.15 8.17 8.18 8.19 8.18 8.20 8.19 8.19 8.20 8.22 8.23 8.21 7.85 7.47 ,34 ,29 ,28 ,27 7.27 7.29 7.32 7.35 8.23 7.27 MAR 7.39 7.75 7.90 7.71 7.73 7.76 7.80 7.82 7.77 7.70 .66 .66 .66 .67 7.71 7.71 7.74 7.74 7.74 7.75 7.76 7.78 8.16 8.14 7.95 7.89 7.87 7.89 7.91 7.92 7.96 8.16 7.39 APR 7.96 7.95 7.96 7.99 8.01 8.02 8.03 8.04 8.05 7.98 7.90 7.85 7.83 7.83 7.80 7.74 7.87 7.84 7.86 7.87 7.96 7.95 7.96 7.96 7.99 7.98 8.05 7.74 MAY 7.94 8.00 8.00 8.01 7.99 8.01 8.04 8.05 8.05 8.06 8.06 8.07 8.06 8.07 8.06 8.05 8.06 8.05 8.05 8.03 8.02 8.00 8.02 8.03 8.05 8.03 8.02 7.97 8.00 7.97 7.97 8.07 7.94 JUN 7.98 7.98 8.00 8.01 8.04 8.06 8.09 8.11 8.13 8.13 8.13 8.14 8.13 8.13 8.12 8.10 8.13 8.14 8.15 8.12 8.11 8.11 8.11 8.11 8.12 8.12 8.12 8.10 8.10 8.11 8.15 7.98 JUL 8.12 8.13 8.16 8.18 8.20 8.23 8.22 8.25 8.26 8.28 8.46 8.49 8.48 8.48 8.49 8.42 8.35 8.34 8.35 8.41 8.42 8.29 8.43 8.45 8.43 8.46 8.45 8.46 8.30 8.45 8.47 8.49 8.12 AUO 8.48 8.52 8.57 8.59 8.59 8.62 8.63 8.60 8.60 8.61 8.63 8.61 8.64 8.64 8.65 8.67 8.68 8.50 8.48 8.30 8.27 8.26 8.20 7.90 7.83 7.79 7.80 8.68 7.79 SEP 7.96 8.03 7.92 8.08 8.08 8.08 8.06 8.04 8.04 8.06 8.05 8.02 7.91 7.75 7.67 7.64 7.66 7.79 7.76 7.75 7.75 7.76 7.72 7.70 7.69 7.70 7.72 7.73 7.76 7.76 8.08 7.64 is "I §_ < uiO N s •*/*i\K\ k. •s/« **tV^/** V* v«A*.- *x J *v /v w w. V. J r ONDJ FMAMJJ ASONDJ FMAMJJ ASONDJ FMAMJJ AS 1988 1989 1990 1991 n?si H H H H H VI *k Ul M H o«0oo«Jot wi » ui M H WATER LEVEU IN FEET BELOW LAND-SURFACE DATUM HHHHH HHHHH M U> VI VI 16 *k n to f MMMMM M M H H H HHHHH HHHHH HHHHH HHHHO IMMM MMMMH HHHMM >M MMMMHH HHHHH HHHHH HHHHH HHH HHHHH MMMMM MMMMM MMMMM MMMMM to eo in eoootMeo H-JHOIH «0i*Hovi H W Ul Ul Ul Ul Ul Ul Ul Ul Ul Ul Ul UIMMMM MMMMM MMMMM HHHHH -JO OOOOI0I0 in in in in in in in in in in in in in in in VI VI VI VI VI VI VI VI VI VI Ot Ot VI VI VI ilk ilk ilk Ul >O VI VI VI VI VI 10 M 10 M H O) O) Ul ... I I I O O 10 I I I llfc H -J I I I in in in in in in in en 9t ot ot ot ot ot ot ot ot ot ot m O) ot ot VI VI 01 10 VI VI VI VI VI I 00 00 00 od od VI VI VI VI VI VI VI VI VI VI VI VI VI VI VI VI VI VI VI VI VI VI VI VI VI oooo*^*^*^ *^oto\otot oto\otoo^0 Q SB 8 OiHH-0 Otn ' f H • P-ODD^i*!*.. ,.- • gibOct oo ot H 0 g*B ° " o * ** « M £88 a D »•& O*0 ui • B S rt - ft g •« 0 tfUl M H Hi I ft B ilk tl 9 •••awBrtiH- OHH rt g S • vi H a ^ er.«-.. • (QD'Mwag,. ^ n | H O A < I H H" OHVHiOH *,H H a ft ft D e • H • bHH- n of 3 • WB 0 « « Ml "Oi M& B'- •J ft to 444 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NUBVO BASINS 182413066044000. Local number, 220. LOCATION.—Lat 18°24'13", long 66°04'40". Owner* P.R. Aqueduct and Sewer Authority. Namei Parque San Luis Rey-Americo Miranda AQUIFER.—Surficial Deposits-Cibao Formation. WELL CHARACTERISTICS.--Drilled unused artesian well, diameter 10 in (0.25 m), cased 8 in (0.20 m) 0-166 ft (0- 50.6 m), perforated 39-166 ft (11.9-50.6 m). Depth 166 ft (50.6 m). DATUM.—Elevation of land-surface datum is about 16.4 ft (5.0 m) above mean sea level, from topographic map. Measuring points Top of shelter floor, 3.00 ft (0.91 m) above land-surface datum. REMARKS.—Recording observation well. Water level* affected by nearby pumping well. PERIOD OF RECORD.—February 1986 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, +2.99 ft (+0.91 m) above land-surface datum, Feb. 6, May 8-9, 1986; lowest water level recorded, 6.48 ft (1.98 m) below land-surface datum, Oct. 26, 1989 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH .44 .34 .20 .02 + .08 + .16 .29 .33 .35 .60 .79 .87 .87 .83 .81 + .86 + .89 +1.04 +1.11 +1.12 +1.12 +1.16 +1.13 +1.10 + .96 + .91 + .78 + .63 + .46 + .30 .19 .44 +1.16 .18 .34 .67 .80 .95 .98 1.13 1.17 1.07 1.08 1.11 1.14 1.18 1.22 1.27 1.30 1.32 1.38 1.43 1.48 1.44 1.44 1.44 1.46 1.50 1.50 1.51 1.51 1.52 1.39 —— 1.52 .18 1.38 1.32 1.23 1.16 1.12 1.14 1.18 1.23 1.25 1.29 1.32 1.38 1.42 1.45 1.49 1.51 1.51 1.52 1.56 1.58 1.60 1.60 1.59 1.57 1.57 1.58 1.56 1.52 1.45 1.29 1.00 1.60 1.00 .69 .64 .58 .57 .52 .47 .43 .42 .44 .45 .50 .53 .56 .62 .68 .73 .75 .81 .87 .91 .92 .95 .99 1.06 1.10 1.12 1.14 1.19 1.20 1.24 1.17 1.24 .42 1.17 1.21 1.19 1.19 1.23 1.15 1.18 1.18 1.20 1.19 1.14 1.13 1.13 1.17 1.22 1.23 1.26 1.23 .92 .64 .44 .35 .34 .35 .38 .42 .43 .38 —— 1.26 .34 .31 .21 .13 .05 .01 + .04 + .04 + .05 .01 .08 .07 .14 .16 .18 .20 .17 .12 .05 .02 .02 + .01 + .09 + .07 + .07 + .12 + .17 + .18 + .16 + .15 + .13 + .12 .31 + .18 + .13 + .17 + .15 + .17 + .16 + .14 + .12 + .17 + .12 + .12 + .18 + .19 + .21 + .23 + .33 + .39 + .48 + .53 + .53 + .49 .47 .46 .40 .39 .38 .40 .39 + .37 + .36 + .34 —— + .12 + .53 + .33 + .32 + .32 + .30 + .29 + .28 + .25 + .28 + .28 + .23 + .22 + .22 + .19 + .19 + .17 + .14 + .11 + .12 + .12 + .17 + .19 + .17 + .13 + .15 + .17 + .16 + .11 + .09 + .09 + .09 + .06 + .06 + .33 + .07 + .03 .02 .03 .03 .04 .06 .09 .io .10 .13 .10 .14 .13 .14 .17 .18 .20 .20 .19 .07 .07 .04 .04 .04 .05 .07 .07 .08 .09 —— .20 + .07 .10 .12 .13 .14 .15 .18 .20 .21 .23 .25 .27 .29 .31 .34 .34 .17 .07 .04 .03 .07 .07 .08 .11 .09 .12 .14 .13 .14 .09 .08 .09 .34 .03 .09 .11 .15 .18 .17 .22 .24 .26 .28 .32 .35 .35 .37 .39 .40 .43 .41 .29 .27 .26 .23 .21 .22 .27 .28 .30 .23 .08 .04 .04 .05 .43 .04 .06 .07 .08 .15 .18 .21 .16 .11 .07 .05 .04 .03 .00 .03 .04 .04 .01 .06 .09 .12 .06 .04 .03 .05 .05 .00 .01 + .09 + .17 + .25 —— .21 + .25 WTR YR 1991 MEAN .31 LOW 1.60 HIGH +1.16 3| |4 U|O s§il * Er 7 'V. - ^ sy /v «r -s VN •NJ -s, ^ J -n c 'fVy}r s^>^r ^^ A/n^ ^\ J >/• y^ %*» XT >r- v^ *^ ONDJFMAMJJASONDJFMAMJJASONDJFMAMJJAS 1988 1989 1990 1991 + Above land-surface datum. GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NOEVO BASINS 445 ») 0-107 ft (0-32.6 m). 182436066031200. Local number, 221. LOCATION.—Lat 18°24'36", long 66°03'12". Ownert P.R. Highway Authority Name i Hyde Park TW-10. AQUIFER.--Surficial Deposits-Cibao Formation. WELL CHARACTERISTICS.—Drilled water-table well, diameter 4 in (0.10 m), cased 4 in (0.10 perforated 19-107 ft (5.79-32.6 m) . Depth 107 ft (32.6 m). DATUM.—Elevation of land-surface datum is about 82.0 ft (25.0 m) above mean sea level, from topographic map. Measuring pointi Hole on side of casing, 0.70 ft (0.21 m) above land-surface datum. Prior July 28, 1986, top of shelter floor, 3.14 ft (0.96 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—December 1985 to February 11, 1991, discontinued. „ .. , 0 EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 0.62 ft (0.19 m) below land-surface datum, Sept. 18, 1989| lowest water level recorded, 15.59 ft (4.75 m) below land-surface datum, Apr. 5, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HI OH OCT 6.88 ,86 ,81 5.68 5.10 4.94 5.28 3.42 2.02 2.54 2.56 2.58 2.59 ,61 ,65 ,70 ,40 4.30 3.33 3.93 58 96 98 38 73 5.09 5.28 5.41 5.66 7.22 2.02 NOV 5.84 5.92 5.94 5.94 6.32 6.44 6.51 6.54 6.68 6.72 6.81 6.85 6.93 7.02 7.09 7.16 7.26 7.37 7.49 7.59 7.43 7.36 7.49 7.60 7.66 7.72 7.71 7.72 7.79 7.50 7.79 5.84 DEC 7.45 7.42 7.14 6.85 6.85 6.97 7.13 7.29 7.37 7.46 7.59 7.70 7.80 7.93 8.03 8.07 8.21 8.30 8.43 8.52 8.62 8.62 8.52 8.53 8.61 8.71 8.65 8.31 7.50 6.96 6.69 8.71 6.69 JAN 6.00 5.49 5.71 5.72 5.65 5.53 5.55 5.55 5.65 5.76 5.94 6.04 6.15 6.30 6.40 6.46 6.54 6.65 6.78 6.86 6.98 7.14 7.24 7.40 7.51 7.64 7.78 7.90 8.01 8.12 8.20 8.20 5.49 FEB 8.21 8.24 8.27 8.28 8.33 8.44 8.60 8.74 8.89 9.02 MAR APR MAY JUN JUL AUG SEP 9.02 8.21 li "I LJU P 10 15 \t \fAJ *N *\^ X V -4/Ir •sN\J r^j^ Vsr ^•i v/A JXHV\1\ \ ONDJFMAMJJASONDJFMAMJJASONDJFMAMJJAS 1988 1989 1990 1991 446 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NDEVO BASINS 182511066045401. Local number, PN-2. LOCATION. --I»t 18<>25'11, long 66»04'54-. Owneri U.S. Geological Survey, WRD. Namei La Esperanxa No. 2. AQUIFER. —Alluvium. NELL CHARACTERISTICS.—Drilled observation well, diameter 4 In (0.10 m), cased 4 In (0.10 m), 0-40 ft (0-12.2 m), perforated 30-40 ft ((9.15-12.2 m). Depth 40 ft (12.2 m). DATUM.—Elevation of land-surface datum !• about 13 ft (3.96 m) above mean sea level, from topographic map. Measuring pointi Hole on well shaft, 3.17 ft (0.97 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—July 1989 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 8.12 ft (2.47 m) below land-surface datum, Oct. 22, 1990; lowest water level recorded, 11.90 ft (3.63 m) below land-surface datum, July 15, 16, 1991. DAY WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO INSTANTANEOUS OBSERVATION AT 1200 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL 1991 AUQ SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 10.21 10.25 10.25 10.04 9.92 9.93 9.88 9.67 9.63 9.36 9.00 8.78 8.80 8.84 8.90 8.96 8.74 8.55 8.33 8.28 8.26 8.13 8.15 8.25 8.27 8.18 8.15 8.24 8.35 8.48 8.64 10.25 8.13 8.78 8.93 9.07 9.19 9.30 9.41 9.51 9.58 9.67 9.75 9.85 9.92 9.97 10.00 10.05 10.11 10.13 10.16 10.23 10.30 10.29 10.27 10.28 10.36 10.38 10.46 10.43 10.36 10.27 10.09 —— 10.46 8.78 9.93 9.90 9.73 9.45 9.32 9.29 9.34 9.42 9.50 9.57 9.68 9.75 9.78 9.81 9.88 9.87 9.76 9.76 9.79 9.85 9.91 9.95 9.94 9.92 9.76 9.73 9.73 9.57 9.31 9.07 8.96 9.95 8.96 8.77 8.60 8.58 8.55 8.49 8.41 8.37 8.34 8.37 8.38 8.38 8.43 8.50 8.61 8.72 8.83 8.92 8.98 9.08 9.17 9.27 9.34 9.44 9.51 9.62 9.70 9.78 9.85 9.95 10.00 10.06 10.06 8.34 10.06 10.06 10.07 10.05 10.04 9.99 9.98 9.96 9.97 10.02 9.89 9.72 9.70 9.70 9.76 9.85 9.91 9.98 9.72 9.19 8.93 8.71 8.67 8.71 8.81 8.88 8.97 9.09 —— —— —— 10.07 8.67 9.20 9.33 9.37 9.43 9.54 9.62 9.67 9.77 9.87 9.93 10.01 10.02 10.09 10.11 10.19 10.25 10.31 10.37 10.33 10.36 10.44 10.51 10.36 10.36 10.40 10.33 10.32 10.36 10.40 10.45 10.54 10.54 9.20 10.58 10.67 10.69 10.60 10.58 10.61 10.62 10.69 10.63 10.64 10.61 10.61 10.51 10.45 10.46 9.97 9.72 9.69 9.67 9.70 9.79 9.88 9.95 10.06 10.10 10.13 10.20 10.26 10.33 10.36 —— 10.69 9.67 10.44 10.48 10.58 10.62 10.62 10.67 10.75 10.77 10.71 10.72 10.77 10.80 10.76 10.80 10.82 10.84 10.90 10.95 10.96 10.95 10.92 10.96 10.99 11.05 11.10 11.05 11.10 11.13 11.16 11.19 11.22 11.22 10.44 11.29 11.30 11.31 11.36 11.37 11.42 11.44 11.50 11.52 11.55 11.57 11.59 11.60 11.66 11.67 11.72 11.75 11.77 11.77 11.80 11.65 11.46 11.44 11.31 11.31 11.35 11.41 11.45 11.51 11.56 —— 11.80 11.29 11.51 11.54 11.59 11.65 11.66 11.71 11.72 11.71 11.76 11.77 11.81 11.84 11.86 11.86 11.90 11.67 11.26 11.11 11.11 11.12 11.15 11.19 11.21 11.26 11.29 11.33 11.34 11.32 11.20 11.19 11.13 11.90 11.11 11.04 11.03 11.05 11.12 11.13 11.17 11.21 11.24 11.29 11.32 11.38 11.42 11.46 11.49 11.53 11.58 11.56 11.25 11.16 11.14 11.05 11.05 11.06 11.10 11.16 11.18 11.25 10.68 10.45 10.42 10.42 11.58 10.42 10.50 10.56 10.60 10.67 10.76 10.82 10.88 10.79 10.52 10.41 10.32 10.28 10.32 10.34 10.37 10.41 10.43 10.37 10.41 10.49 10.29 10.18 10.07 10.05 10.08 9.89 9.83 9.56 9.50 9.32 —— 10.88 9.32 WTR YR 1991 MEAN 10.23 LOW 11.90 HIOH 8.13 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM N> <0 O> y / V ^ /\ ' \ \x/7ALAr*J^A /rv(0\1VfiN XTsTV^ ASONDJ FMAMJJ ASONDJ FMAMJJ AS 447 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NOBVO BASINS 182435066052700. Local number, PN-5. LOCATION.—Lat 18°24'35 I> , long 66»05'27 B . Owneri U.S. Geological Survey, WRD. Namei Salud Mental No. 1. AQUIFER. —Alluvium. WELL CHARACTERISTICS.—Drilled water-table well, diameter 4.0 in (0.10 m), cased 4.0 in (0.10 m), 0-83 ft (0-25.3 m), perforated 73-83 ft (22.2-25.3 m). Depth 83 ft (25.3 m). DATUM.—Elevation of land-surface datum is about 85 ft (25.9 m) above mean sea level, from topographic map. Measuring points Hole on well shaft, 2.85 ft (0.87 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—April 1989 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 26.20 ft (7.98 m) below land-surface datum, Nov. 21, 22, 1989; lowest water level recorded, 30.01 ft (9.15 m) below land-surface datum, Sept. 24, 25, 1991. HATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JXJIi AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 28.80 28.79 28.78 28.78 28.77 28.75 28.73 28.70 28.69 28.65 28.54 28.49 28.36 28.25 28.16 28.06 27.97 27.88 27.80 27.76 27.67 27.54 27.41 27.28 27.18 27.09 27.04 26.99 26.91 26.87 26.82 28.80 26.82 26.79 26.79 26.79 26.77 26.75 26.73 26.73 26.70 26.68 26.67 26.64 26.64 26.63 26.63 26.63 26.61 26.61 26.61 26.61 26.61 26.61 26.61 26.64 26.70 26.70 26.70 26.72 26.72 26.76 26.79 —— 26.79 26.61 26.85 26.86 26.88 26.88 26.88 26.88 26.88 26.88 26.88 26.88 26.88 26.89 26.90 26.91 26.95 26.96 26.96 26.97 26.99 27.00 27.00 27.01 27.03 27.03 27.06 27.11 27.12 27.13 27.12 27.12 27.12 27.13 26.85 27.08 27.04 27.01 26.96 26.88 26.81 26.75 26.64 26.57 26.53 26.50 26.47 26.33 26.31 26.30 26.29 26.29 26.29 26.29 26.29 _-_ —— —— 26.31 26.31 26.31 26.33 26.35 26.42 26.45 27.08 26.29 26.48 26.51 26.53 26.55 26.60 26.62 26.68 26.71 26.74 26.78 26.78 26.82 26.85 26.90 26.93 26.95 26.96 26.98 26.87 26.88 26.93 26.89 26.89 26.86 26.83 26.79 26.76 26.74 —— —— —— 26.98 26.48 26.73 26.71 26.70 26.71 26.71 26.71 26.72 26.74 26.75 26.76 26.80 26.83 26.85 26.89 26.94 26.96 27.00 27.01 27.02 27.05 27.11 27.14 27.16 27.19 27.22 27.23 27.27 27.30 27.34 27.36 27.38 27.38 26.70 27.41 27.43 27.46 27.47 27.48 27.51 27.60 27.63 27.65 27.69 27.72 27.74 27.76 27.78 27.80 27.74 27.79 27.79 27.80 27.81 27.81 27.82 27.85 27.86 27.86 27.87 27.88 27.89 27.91 27.92 —— 27.92 27.41 27.95 27.96 27.98 28.01 28.02 28.04 28.05 28.07 28.10 28.14 28.17 28.18 28.22 28.25 28.28 28.29 28.33 28.36 28.38 28.38 28.41 28.43 28.37 28.39 28.40 28.40 28.42 28.43 28.44 28.51 28.55 28.55 27.95 28.58 28.62 28.64 28.66 28.67 28.69 28.71 28.72 28.74 28.77 28.80 28.84 28.85 28.90 28.92 28.94 28.96 28.97 29.00 29.01 29.02 29.03 29.05 29.09 29.12 29.14 29.16 29.17 29.19 29.20 —— 29.20 28.58 29.21 29.22 29.25 29.26 29.29 29.30 29.32 29.33 29.35 29.36 29.38 29.38 29.39 29.41 29.43 29.40 29.43 29.44 29.49 29.49 29.49 29.49 29.49 29.50 29.53 29.57 29.57 29.58 29.58 29.59 29.60 29.60 29.21 29.61 29.62 29.64 29.66 29.66 29.67 29.67 29.68 29.69 29.70 29.72 29.73 29.74 29.75 29.76 29.78 29.78 29.73 29.82 29.82 29.82 29.82 29.84 29.85 29.86 29.88 29.90 29.88 29.90 29.91 29.92 29.92 29.61 29.93 29.93 29.93 29.93 29.93 29.94 29.96 29.96 29.96 29.96 29.96 29.96 29.96 29.96 29.96 29.97 29.97 29.97 29.97 29.99 29.99 29.99 29.99 30.00 30.01 29.99 29.99 29.96 29.97 29.94 —— 30.01 29.93 25 27 29 31 MJJ ASONDJ F M A M J J ASONDJ FMAMJJ AS 1989 1990 1991 448 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NUBVO BASINS 182445066043401. Local number, PN-6. LOCATION.—Lat 18«24 / 45", long 660 04'34". Owners U.S. Geological Survey, WRD. Namai AlBacia No. 2. AQUIFER.--Alluvium. __ . NELL CHARACTERISTICS.—Drilled obMrvation well, diameter 4 in (0.10 m), cased 4 in (0.10 m), 0-27 it (0-8. JJ mj, perforated 21-27 ft (6.40-8.23 m). Depth 27 ft (8.23 m). DATUM.--Elevation of land-surface datum i« about 10 ft (3.05 m) above mean sea level, from topographic map. Measuring points Hole on well shaft, 3.03 ft (0.91 m) above land-surface datum. REMARKS.—recording observation well. PERIOD OF RECORD.—July 1989 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 3.11 ft (0.95 m) below land-surface datum, Sept. 18, 1989; lowest water level recorded, 8.41 ft (2.56 m) below land-aurface datum, Aug. 15, 1991. HATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 7.00 6.93 6.71 6.50 6.42 6.32 6.19 6.10 6.10 5.64 5.38 5.42 5.47 5.52 5.54 5.44 5.27 5.10 .83 .88 .64 .58 .70 .87 .98 4.96 5.04 5.23 5.41 5.59 5.79 7.00 4.58 6.00 6.21 6.40 6.52 6.59 6.71 6.83 6.85 6.99 7.11 7.20 7.24 7.30 7.32 7.37 7.39 7.41 7.46 7.51 7.53 7.43 7.40 7.40 7.46 7.48 7.49 7.47 7.47 7.46 7*35 7.53 6.00 7.27 7.19 7.08 7.01 6.98 7.02 7.08 7.14 7.17 7.22 7.28 7.33 7.37 7.42 7.44 7.42 7.42 7.44 7.50 7.52 7.60 7.62 7.65 7.57 7.56 7.55 7.51 7.45 7.27 7.17 7.04 7.65 6.98 6.61 6.54 6.51 6.46 6.39 6.32 6.26 6.23 6.23 6.23 6.22 6.33 6.37 6.46 6.59 6.68 6.75 6.82 6.90 7.00 7.05 7.10 7.13 7.22 7.28 7.32 7.36 7.42 7.45 7.50 7.51 7.51 6.22 7.47 7.54 7.56 7.58 7.60 7.49 7.48 7.47 7.51 7.57 7.46 7.42 7.41 7.42 7.50 7.57 7.61 7.62 7.07 6.60 __ —— __ —— 7.62 6.60 —— _-- ___ —— __ __- —— _ _ —— —— _ _ ___ ___ —— 7.02 7.01 7.06 7.08 7.12 7.17 7.17 7.01 7.17 7.17 7.18 7.09 7.09 7.12 7.18 7.15 7.12 7.13 7.15 7.13 7.07 7.09 6.84 6.57 6.48 6.47 6.46 6.50 6.57 6.63 6.67 6.70 6.75 6.75 6.79 6.85 6.90 6.96 —— 7.18 6.46 7.02 7.06 7.09 —— _-- ___ —— — :_ ___ 7.47 7.49 7.49 7.48 7.47 7.53 7.56 7.59 7.62 7.62 7.02 7.62 7.66 7.70 7.76 7.76 7.77 7.79 7.80 7.78 7.81 7.82 7.81 7.87 7.90 7.86 7.90 7.93 7.95 7.93 7.88 7.70 7.62 7.58 7.57 7.57 7.66 7.72 7.71 7.76 7.74 7.95 7.57 7.75 7.79 7.82 7.85 7.92 7.96 7.97 7.99 8.01 8.04 8.06 8.08 8.12 8.13 8.17 —— ___ _-- 7.61 7.68 7.75 7.77 7.80 7.83 7.82 7.70 7.70 7.70 8.17 7.61 7.74 7.79 7.86 7.89 7.86 7.95 8.00 8.06 8.14 8.20 8.24 8.25 8.28 8.28 8.30 8.35 8.25 7.91 7.87 7.89 7.81 7.83 7.83 7.94 8.01 8.08 7.96 7.70 7.68 7.72 7.74 8.35 7.68 7.81 7.84 7.90 8.03 8.13 8.18 8.21 7.97 7.80 7.75 7.69 7.71 7.72 7.78 7.87 7.94 7.93 8.00 8.10 8.18 7.97 7.89 7.84 7.90 7.93 7.80 7.84 7.58 7.52 7.39 8.21 7.39 o g . Vv J AS 1989 ON DJ F 1990 M A M J J ASON OJ F 1991 M A M J J AS 449 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NUBVO BASINS 182437066040500. Local number, PN-7. LOCATION.—Lat 18°24'37", long 66°04'05". Owneri U.S. Geological Survey, WRD. Namei Parque de la« Fuentei No. 1. AQUIFER.--Alluvium. WELL CHARACTERISTICS.—Drilled observation well, diameter 4 in (0.10 m), caied 4 in (0.10 m), 0-52 ft (0-15.8 m), perforated 42-52 ft (12.8-15.8 m). Depth 52 ft (15.8 m). DATUM.--Elevation of land-«urface datum !• about 23 ft (7.01 m) above mean «ea level, from level*. Measuring pointi Hole on well shelter floor, 3.20 ft (0.98 m) above land-«urface datum. REMARKS.--Recording observation well. Formerly published a« 182437066040501, Parque de la« Fuentei No. 2, which i« another well. PERIOD OF RECORD.—February 1989 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 6.50 ft (1.98 m) below land-«urface datum, Sept. 27, 1989; loweit water level recorded, 12.60 ft (3.84 m) below land-«urface datum, Aug. 16, 17, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 9.08 9.05 8.86 8.64 8.48 8.39 8.26 8.17 8.19 7.76 7.42 7.31 7.35 7.42 7.51 7.58 7.49 7.30 6.98 6.92 6.82 6.70 6.75 6.87 6.93 6.89 6.90 7.03 7.15 7.32 7.45 9.08 6.70 NOV 7.61 7.76 7.92 8.03 8.18 8.24 8.30 8.39 8.46 8.54 8.63 8.68 8.73 8.80 8.86 8.90 8.91 8.95 9.04 9.13 9.13 9.13 9.17 9.19 9.25 9.31 9.30 9.29 9.28 9.17 9.31 7.61 DEC 9.08 9.00 8.88 8.75 8.68 8.68 8.68 8.72 8.78 8.83 8.87 8.94 8.97 9.04 9.11 9.12 9.12 9.13 9.15 9.18 9.23 9.33 9.32 9.31 9.30 9.32 9.48 9.41 9.22 8.93 8.78 9.48 8.68 JAN 8.47 8.27 8.22 8.24 8.19 8.12 8.02 7.99 7.99 8.03 8.07 8.13 8.18 8.22 8.33 8.37 8.43 8.51 8.58 8.62 8.68 8.78 8.89 9.07 9.29 9.38 9.37 9.37 9.37 9.38 9.39 9.39 7.99 FBB 9.39 9.39 9.39 9.40 9.41 9.35 9.34 9.40 9.40 9.40 9.41 9.39 9.37 9.37 9.39 9.43 9.50 9.54 9.16 8.72 8.48 8.27 8.22 8.21 8.24 8.27 8.36 8.40 9.54 8.21 MAR 8.47 8.50 8.54 8.58 8.61 8.65 8.69 8.72 8.76 8.79 8.83 8.87 8.90 8.94 8.98 8.98 8.99 8.99 8.99 8.99 9.01 8.98 00 01 01 06 9.11 9.11 8.47 APR 9.13 9.15 9.17 9.14 9.13 9.12 9.12 9.15 9.14 9.15 9.14 9.13 9.03 8.98 8.89 8.58 8.48 8.43 8.42 8.43 8.45 8.49 8.56 8.62 8.65 8.66 8.68 8.74 8.82 8.86 9.17 8.42 MAY 8.90 8.95 8.98 9.01 9.02 9.11 9.18 9.20 9.23 9.28 9.31 9.35 9.36 9.38 9.45 9.48 9.50 9.53 9.53 9.54 9.50 9.51 9.53 9.53 9.54 9.54 9.56 9.61 9.91 10.25 10.47 10.47 8.90 JUN 10.67 10.80 10.89 11.03 11.10 11.20 11.29 11.33 11.30 11.29 11.32 11.36 11.41 11.51 11.55 11.57 11.60 11.64 11.72 11.86 11.87 11.76 11.63 11.51 11.52 11.61 11.70 11.77 11.81 11.78 11.87 10.67 JUL 11.74 11.81 11.90 11.97 11.99 12.03 12.03 12.02 12.04 12.18 12.32 12.37 12.28 12.16 12.29 11.97 11.72 11.62 11.62 11.65 11.63 11.63 11.73 11.84 11.92 11.89 11.66 11.55 11.25 11.08 10.97 12.37 10.97 AUQ 10.85 11.05 11.30 11.47 11.54 11.68 11.82 11.95 12.07 12.16 12.23 12.25 12.33 12.43 12.51 12.59 12.57 12.25 12.20 12.20 12.18 12.34 12.49 12.52 12.50 12.56 12.11 12.05 12.02 12.06 12.59 10.85 SEP 12.07 12.07 12.05 12.18 12.29 12.37 12.42 12.17 11.91 11.84 11.80 11.85 11.91 12.02 12.04 12.04 12.11 12.15 12.23 12.32 12.03 11.84 11.68 11.67 11.70 11.64 11.61 11.20 11.01 10.78 12.42 10.78 WATER LEVEL, IN FEET BELC LAND-SURFACE DATUM W U CO -J C . V ~\_ /^v\^\ ^ »^,r\n. A / -j 1 'f\•v r\ M^4 H v SA^Lft MJJASONDJFMAMJJASONDJFMAMJJAS 1989 1990 1991 450 (WOUND-WATER LEVELS RIO HONDO TO RIO PUERTO NUBVO BASINS 182443065041502. Local number, PN-8c. LOCATION.—Lat 18°24'43', long «6»04'15-. Owners U.S. Geological Survey, WRD. Namei Parque Luis Mufios Marin 1C. AQUIFER. —Alluvium. NELL CHARACTERISTICS.—Drilled observation well, diameter 4 in (0.10 m), cased 4 in (0.10), 0-33 ft (0-10.05 m), perforated 33-40 ft (10.06-12.2 m) . Depth 40 ft (12.2 m). DATDM.—Elevation of land-surface datum is about 13 ft (3.96 m) above mean sea level, from topographic map. Measuring pointt Hole on well shaft, 3.66 ft (1.12 m) above land-surface datum. REMARKS.—Recording observation wall. PERIOD OF RECORD.—February 1989 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 10.35 ft (3.15 m) below land-surface datum, Sept. 25, 1989; lowest water level recorded, 15.38 ft (4.69 m) below land-surface datum, Aug. 15, 16, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUQ SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HI OH 14.28 14.36 13.99 13.92 13.79 13.74 13.59 13.49 13.55 12.82 11.98 11.99 12.01 12.12 12.27 12.35 12.32 11.85 11.17 11.15 10.61 10.59 10.73 10.95 10.96 10.82 11.01 11.22 11.43 11.65 11.88 14.36 10.59 12.08 12.28 12.45 12.61 12.78 12.99 13.14 13.27 13.38 13.48 13.56 13.64 13.70 13.80 13.88 13.93 13.99 14.07 14.12 14.16 14.15 14.17 14.25 14.29 14.34 14.34 14.30 14.31 14.35 14.24 —— 14.35 12.08 14.10 14.14 13.89 13.89 13.89 13.91 13.95 14.01 14.05 14.09 14.13 14.16 14.20 14.25 14.28 14.28 14.31 14.33 14.38 14.41 —— —— —— —— 14.41 13.89 —— —— ___ —— —— —— —— _-_ —— ___ —— 13.78 13.85 13.91 13.97 14.05 14.09 14.09 14.09 13.78 14.15 14.18 14.22 14.26 14.04 14.14 14.22 14.26 14.30 14.30 14.29 14.31 —— 14.38 14.40 14.41 14.40 13.49 13.06 13.03 12.79 12.69 12.72 12.80 12.92 13.00 13.10 —— 14.41 12.69 13.22 13.26 13.33 13.41 13.48 13.53 13.59 13.66 13.73 13.81 13.88 13.94 13.99 14.02 14.05 14.08 14.11 14.09 14.12 14.17 14.19 14.02 14.11 14.17 14.22 14.17 14.22 14.26 14.27 14.29 14.31 14.31 13.22 14.31 14.32 14.31 14.33 14.34 14.35 14.36 14.35 14.32 14.34 14.36 14.36 14.23 14.29 14.22 13.73 13.73 13.73 13.78 13.82 13.86 13.91 13.96 14.01 14.04 14.04 14.08 14.12 14.16 14.20 14.36 13.73 14.22 14.24 14.25 14.30 14.13 14.21 14.26 14.27 14.33 14.36 14.36 14.37 14.43 14.44 14.48 14.49 14.51 14.51 14.48 14.50 14.43 14.50 14.54 14.56 14.57 14.58 14.58 14.60 14.64 14.70 14.74 14.74 14.13 14.77 14.78 14.81 14.85 14.85 14.88 14.90 14.94 14.96 14.96 14.99 15.00 15.02 15.03 15.04 15.06 15.07 15.08 15.06 15.05 14.96 14.93 15.01 15.03 15.06 15.08 15.11 15.11 15.14 15.15 15.15 14.77 15.12 15.16 15.19 15.17 15.20 15.22 15.23 15.23 15.23 15.26 15.29 15.30 15.31 15.30 15.32 14.75 14.91 15.01 15.03 15.07 15.08 15.09 15.12 15.15 15.18 15.20 15.17 15.17 14.92 15.00 15.01 15.32 14.75 15.03 15.07 15.09 15.13 15.11 15.16 15.20 15.22 15.25 15.27 15.29 15.30 15.32 15.35 15.36 15.38 15.19 14.90 15.05 15.11 15.03 14.97 15.08 15.18 15.20 15.24 15.17 14.79 14.89 14.93 14.99 15.38 14.79 15.03 15.03 15.05 15.09 15.13 15.17 15.20 15.08 15.03 15.05 15.03 15.03 15.04 15.07 15.09 15.10 15.13 15.14 15.18 15.21 15.07 15.06 15.04 15.07 15.06 14.98 14.97 14.50 14.44 14.29 15.21 14.29 §m f P 13 17 fr ;f^AH^-^X JN \ K> MJJ ASONOJ FMAMJJ ASONDJ FMAMJJ AS 1989 1990 1991 3 Hi 1 g! 3 K O VO 00 -J Ot (/I «k Ut M H* O VO 00 -J O\ I >O 90 O £> gi § is Hpsa^ PHJ WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM too 09 (O (O CO 01 00 I -J 00 I M (-« M 10 C« «O «•> I/I ',ISi8', "3*8 i H-H •• > i 10 --o- COiBrr » H B fi • o BoiB-o o-P-o MM ? p Mi«n o H ik o ooo o. * o -ft h( M ft CT BB H I I • IQ h> V 0 0 0 V VO I H--J H n w ^** i— T ^^ w * 3', 58I?S» O I H O • 0 «H O «O u *• O) gS B 2 2a —o "s sr° ^i Eg- a? §? §s ft ss io 5 ft i ~. s&- s O M OH K K H H H M -J I 10 10 10 10 10 U 10 10 fc » S B «s &* ft M i: 01 452 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NUBVO BASINS 182349066032600. Local number, PN-13. LOCATION.--Lat 18«23'49", long 66°03'26". Owners U.S. Geological Survey, WRD. Name i Jardin Botinico No. 1. AQUIFER.--Alluvium. WELL CHARACTERISTICS.—Drilled water-table well, diameter 4 in (0.10 m) cased 4.0 in (0.10 m), 0-45 ft (0-13.72 m), perforated 35-45 ft (10.67-13.72 m). Depth 45 ft (13.72 m). DATUM.--Elevation of land-surface datum is about 32 ft (9.75 m) above mean sea level, from topographic map. Measuring points Hole on well shaft, 2.84 ft (0.86 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.—March 1989 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 8.75 ft (2.67 m) below land-surface datum, Sept. 18, 1989; lowest water level recorded, 16.88 ft (5.14 m) below land-surface datum, Sept. 20, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 16.12 16.10 15.19 15.71 15.74 15.72 15.23 15.64 15.75 15.26 14.45 15.28 15.36 15.49 15.55 15.66 15.67 15.17 14.85 15.22 13.25 15.01 15.28 15.36 15.16 14.95 15.29 15.37 15.50 15.56 15.65 16.12 13.25 NOV 15.69 15.72 15.74 15.79 15.75 15.87 15.88 15.90 15.93 15.94 16.00 16.03 16.05 16.06 16.06 16.09 16.07 16.14 16.14 16.15 16.11 16.09 16.13 16.15 16.17 15.97 15.98 16.03 16.09 15.93 16.17 15.69 DEC 15.35 15.50 14.83 15.72 15.79 15.85 15.89 15.91 15.93 15.93 16.14 16.14 16.00 15.99 16.17 16.18 16.15 15.58 15.36 15.71 15.65 16.18 14.83 JAN 15.38 15.53 15.68 15.65 15.37 15.51 15.46 15.55 15.53 15.48 FEB 16.10 16.17 16.13 16.17 16.20 15.89 15.96 16.09 16.11 16.14 MAR 15.74 15.75 15.83 15.85 15.88 15.90 15.91 15.94 15.96 16.00 15.95 15.97 15.98 16.00 16.02 16.05 16.09 16.10 16.13 16.13 16.05 16.13 15.37 15.29 15.31 15.37 15.49 15.53 15.58 15.68 15.72 16.21 14.95 16.22 15.02 16.10 16.19 16.22 16.17 16.16 16.19 16.19 16.22 16.23 16.23 15.02 APR 16.23 16.25 16.19 16.29 16.28 16.32 16.34 16.10 16.27 16.30 15.95 15.93 15.95 15.95 16.01 15.89 16.05 16.06 16.10 16.11 15.60 15.56 15.68 15.74 15.76 15.78 15.78 15.85 15.89 15.92 16.10 16.09 16.12 16.16 16.18 16.20 16.21 16.12 15.17 14.95 16.05 16.06 16.08 16.09 16.11 16.13 16.17 16.08 16.17 16.21 16.35 16.36 16.16 16.32 16.37 16.04 16.20 16.21 16.22 16.22 16.24 16.27 16.31 16.33 16.35 16.31 16.36 16.39 16.40 16.42 16.42 16.04 MAY 16.44 16.44 16.44 16.46 16.12 16.24 16.29 16.26 16.34 16.35 16.33 16.27 16.42 16.43 16.44 16.43 16.46 16.41 16.37 16.39 16.26 16.40 16.46 16.49 16.41 16.50 16.48 16.52 16.53 16.54 16.56 16.56 16.12 JUN 16.56 16.57 16.58 16.59 16.59 16.63 16.63 16.64 16.65 16.65 16.67 16.67 16.68 16.69 16.68 16.70 16.71 16.71 16.65 16.67 16.50 16.42 16.58 16.60 16.64 16.66 16.67 16.68 16.69 16.69 16.71 16.42 JUL 16.66 16.70 16.71 16.68 16.72 16.73 16.74 16.75 16.74 16.77 16.78 16.79 16.79 16.79 16.81 15.55 16.40 16.54 16.60 16.62 16.65 16.67 16.69 16.71 16.71 16.73 16.71 16.75 16.46 16.63 16.67 16.81 15.55 AUG 16.70 16.73 16.71 16.75 16.73 16.75 16.77 16.82 16.82 16.85 16.85 16.82 16.84 16.84 16.82 16.85 16.74 16.55 16.71 16.76 16.67 16.51 16.62 16.75 16.77 16.79 16.42 16.43 16.66 16.72 16.77 16.85 16.42 SEP 16.79 16.78 16.81 16.84 16.86 16.87 16.86 16.76 16.79 16.81 16.79 16.82 16.81 16.83 16.85 16.84 16.74 16.83 16.86 16.88 16.81 16.47 16.78 16.80 16.79 16.76 16.78 16.62 16.39 16.43 16.88 16.39 HTR YR 1991 MEAN 16.19 LOW 16.88 HIGH 13.25 Si m SA *5r 10 14 18 MJJASONDJFMAMJJASONDJFMAMJJAS 1989 1990 1991 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NOBVO BASINS 453 182406066034700. Local number, PN-19. LOCATION. —Lat 18<>24'06", long 66°03'47". Owneri U.S. Geological Survey, WRD. Namei Jardln Botanico No. 3. AQUIFER. —Alluvium. WELL CHARACTERISTICS.—Drilled water-table well, diameter 4 in (0.10 m) cased 4.0 in (0.10 m), 0-48 ft (0-14.6 m), perforated 38-48 ft (11.6-14.6 m). Depth 48 ft.(14.6 m). DATUM.—Elevation of land-surface datum is about 32 ft (9.75 m) above mean sea level, from topographic map. Measuring pointi Hole on well shaft, 2.91 ft (0.88 m) above land-surface datum. RBHARKS.—Observation well. Automatic digital recording installed on June 13, 1991. PERIOD OF RECORD.—June 1991 to September 1991 EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 6.37 ft (1.94 m) below land-surface datum, Sept. 30, 1991; lowest water level recorded, 7.87 ft (2.40 m) below land-surface datum, Aug. 17, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HI OH OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP —— —— —— —— — — __ —— —— —— __- 7.29 7.31 7.35 7.38 7.40 7.43 7.45 7.44 7.33 7.13 7.11 7.08 7.05 7.05 7.07 7.08 7.09 7.10 —— 7.45 7.05 7.10 7.14 7.18 7.21 7.26 7.29 7.34 7.38 7.43 7.47 7.54 7.57 7.59 7.66 7.69 7.38 7.09 7.06 7.05 7.06 7.06 7.10 7.11 7.14 7.19 7.26 7.27 7.30 7.26 7.24 7.24 7.69 7.05 7.24 7.26 7.28 7.36 7.38 7.43 7.47 7.56 7.60 7.68 7.71 7.73 7.75 7.78 7.80 7.85 7.87 7.57 7.51 7.50 7.51 7.51 7.52 7.59 7.66 7.66 7.68 7.16 7.10 7.09 7.10 7.87 7.09 7.15 7.27 7.34 7.44 7.44 7.47 7.47 7.45 7.30 7.28 7.16 7.13 7.11 7.14 7.18 7.27 7.29 7.37 7.45 7.48 7.18 7.13 7.10 7.09 7.09 6.98 6.97 6.59 6.57 6.39 —— 7.48 6.39 JUNE JULY AUGUST 1991 SEPTEMBER 454 GROUND-WATER LEVELS RIO GRANDE DE LOIZA BASIN 182515065594100. Local number, 222. LOCATION.—Lat 18«25'15", long 65«59'41". Owners U.S. Geological Survey. Name i Campo Rico TW-1. AQUIFER.--Surficial Deposits. WELL CHARACTERISTICS.—Drilled unused water-table well, diameter 4 in (0.10 m). Depth 100 ft (30.5 m). DATUM.—Elevation of land-surface datum is about 10.0 ft (3.05 m) above mean sea level, from topographic map. Measuring pointt Hole on side of casing, 0.80 ft (0.24 m) above land-surface datum. Prior July 28, 1986, top of shelter floor, 3.10 ft (0.94 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—February 1986 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 4.42 ft (1.35 m) below land-surface datum, Aug. 31, 1986; lowest water level recorded, 7.42 ft (2.26 m) below land-surface datum, Feb. 9, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 6.20 5.60 5.56 5.56 5.75 5.90 5.91 5.88 6.07 5.98 5.72 5.63 5.52 5.35 5.38 5.27 5.28 5.38 5.47 5.50 5.56 5.71 5.71 5.71 5.75 5.72 5.70 5.66 6.20 5.27 NOV 5.56 5.47 5.51 5.55 5.71 5.91 6.06 6.12 6.20 6.29 6.20 6.09 5.97 5.86 5.83 5.83 5.77 5.76 5.79 5.92 5.89 5.97 6.15 6.14 6.20 6.37 6.34 6.21 5.97 5.71 6.37 5.47 DEC 5.67 5.69 5.61 5.80 5.94 5.99 6.06 6.07 6.18 6.12 6.10 6.00 6.11 6.04 6.05 6.04 6.14 6.05 6.11 6.19 6.26 6.21 6.17 6.03 6.08 6.15 6.18 6.14 6.04 5.97 5.90 6.26 5.61 JAN 5.85 5.93 6.08 6.16 6.19 6.30 6.28 6.23 6.20 6.22 .20 .16 .13 .18 .21 .18 .16 6.27 6.24 6.17 6.19 6.16 6.17 6.31 6.19 6.13 6.06 5.98 6.10 6.31 5.85 FEB 6.09 6.10 6.23 6.22 6.19 6.19 6.19 6.23 6.20 6.14 6.13 6.18 6.19 6.18 6.14 6.16 6.20 6.29 6.34 6.33 6.53 6.58 6.49 6.40 6.35 6.28 6.24 6.19 6.58 6.09 MAR 6.31 6.33 6.40 6.33 6.37 6.41 6.46 6.45 6.40 6.28 .23 .18 .21 .25 .34 .27 .38 .39 .34 .34 .39 .41 .60 .63 .52 .40 .38 .47 .51 .52 .60 6.63 6.18 APR 6.66 6.61 6.59 6.56 6.63 6.58 6.50 6.51 6.55 6.50 6.38 6.31 6.28 6.37 6.26 6.21 6.38 6.34 6.35 6.29 6.26 6.34 6.39 6.40 6.42 6.45 6.40 6.31 6.36 6.35 6.66 6.21 MAY 6.35 6.37 6.36 6.28 6.31 6.39 6.44 6.50 6.48 6.54 6.49 6.42 6.41 6.32 6.32 6.31 6.32 6.30 6.30 6.36 6.41 6.41 6.42 6.45 6.49 6*38 6.38 6.33 6.26 6.09 6.07 6.54 6.07 JUN 5.09 5.06 6.08 5.15 6.23 6.23 6.33 6.37 6.38 6.41 .35 .26 .13 .10 .06 .08 .23 .36 .33 .44 .47 .37 .38 .41 .40 .28 .18 .18 .13 .11 6.47 6.06 JUL 6.16 6.20 6.32 6.37 6.45 6.54 6.62 6.69 6.67 6.62 6.45 6.29 6.14 6.11 6.16 6.22 6.29 6.39 6.52 6.66 6.64 6.63 6.58 6.47 6.42 6.39 6.23 6.21 6.19 6.20 6.17 6.69 6.11 AUG 6.17 6.25 6.35 6.40 6.45 6.56 6.47 6.31 6.10 5.88 6.22 6.29 6.31 6.38 6.33 6.28 6.15 6.01 5.92 5.81 6.56 5.73 SEP 6.04 6.06 6.15 6.16 6.02 5.83 5.69 5.47 5.49 5.53 5.65 5.67 5.73 5.73 5.74 5.78 5.83 5.77 5.74 5.59 5.45 5.37 5.33 5.18 5.12 5.15 5.21 5.30 5.51 5.60 6.16 5.12 WTR YR 1991 MEAN 6.13 LOW 6.69 HIGH 5.12 0 N D J F M 1988 1989 AMJJASON D J F M 1990 AMJJ ASON 0 J F M 1991 AMJJ AS si Ot000-I0t VlfcWMH WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM -I M M H ( le in (0 R R FO § HO JO » OB 9 <-n> I'-Bofc-ssap I seo HW rt. soeuv RI .5 ti po 09 00 8- > M O Z O <_ •n £ > Z <_ <_ > O Z o in vi o o -J -J fc fc fc HHH i «e 10 10 i i 1 M U> -1 1 1 u> u>u> wu> u> -1 -1 01 0) VI fc M 0 00 fc VI 01 VI VI fc W M H u> H u> u> fc in 0909 09 1 | | w CO -1 1 1 1 -1 10 10 -1 «J «J «J -1 00 0 H M fc 0) 0 VI 01 -IH 01 M 00000 1 fc IA) IA) W M 1 U> 00 W 0 00 VI VI VI VI VI VI M M M H H H 00 -1 01 01 01 VI VI VI VI VI VI i o«e oo -i 0) 1 -1 01 01 01 -1 vi in in vi vi vi «J -i 01 01 in in W 0 0) H -I W in in in in in in O 10 10 09 -1 -1 «J 09 0 U> 0) 0 i i i i i i i i i i u>u> u>u> w "oo OM vi OO 10 -1 01 100 0 10 -1 09 00 09 00 00 -I 01 in fc w M fc in 0) -i 00 00 09 10 10 M fc «J U> 00 WH M fc M o o o o o M W U> M M 00 H M 00 W in vi in in in H H HH H vi in in in vi inin fc u> u> «0H fc OOH in in in in in in fc fc fc M ooo in H 0i in in in in in 0101 01 01 01 01 01 in in in fc H >0 «J in 1 1 1 O O 1 1 1 M 10 MMMM M 10 10 00 -1 -1 00 H fc 00 W VI fc U» M H -1 «J -1 01 0) 00 00 00 -1 -1 MH o 10 oo -1 00 -l-l 01 10 10 10 10 O 09 00 09 10 0 W 0 0101 -1 O O O O 10 HH 00 10 -i vi 10 o o vi in in in in H H H H H vi vi in in in M H 0 10 00 u in 0t-i oo in in in in in U» M H H O H in 10 fc >0 in in in in in mm fc fc fc M 0 09 «J 01 M M M M M M W VI 0(0 H VI H-IO M M MM M 0t 0) 0) 0i in 09 U> U> O U> 0 w CO -101 «J 01 01 fc W -l-l -1 -l-l •J 01 VI W M VIM H <0 00 a o o 10 10 H H 0«0 00 01 fc 01 -1 00 10 10 10 10 10 •j 0i infc fc w CO 00 10 O vi in vi in vi HH HH H in in vi vi vi «j 01 01 in fc 10 10 00 0 in in vi in in 0 0 10 10 10 in M 10 -i fc in in in in in fc M M H H M fc in 10 oo M fc «J 0 fc M 0) VI -1 W M M M M M fc CJ M M H VI OOH VI 00 infc M H 0 M 0 00 01 VI -1 -1 01 01 01 K O 10 -1 01 W H 00 01 10 10 10 10 10 -i-i 01 in fc 10 H M fc VI 10 10 09 00 00 M 0 00 01 lot -1 10 -J U> «J in in vi m in H H HH 0 vi vi in in in u> u> u> u> M U> M H 0 10 H M fc in fc in in vim in in in in in in 09 00 «J «J 01 10 VI 10 M fc in in in in in H-SSSM fc VI VI 01 01 -1 M 0|M -J O 10 O -1 O 10 < M M M H H H 0 0 10 «0 H to 09 U> 09 in O 10 00 -l-l -J > W H 0tfc W 2| 0101 01 01 01 mm fcfc in H -IH 00 00 M B M M MH 0 P -1 10 H fc 0t V) 00 M H O Z m m m m m m m m m in in fc w M H a 01 oo oo 01 -i r in m m m vi o o M fc 01 a -j 09 H in in o a 3 9 i!>§ -SURF AC! IBOUS OI 8 2* Sg IM £a H S s* 0 H °5 Q CTOBBR 1 <0o 4O 3 » H 10 H SSISo^oSS 11 ffoo'oS "M?* Humif • • V Mi Mi H 0 ft H ^ M 0i • 0 U> » i HI H? >rr ? VOH CO m MI O fl ^. oo It • 0 in • O « M • -IK) . •> W -J a -a fc rt «0H- 0 g 090 S 1 i* M „ I I I I . I I I I VI I I I I 00 en en 456 GROUND-WATER LEVELS RIO HUMACAO TO RIO SBCO BASINS 180415065513900. Local number, 96. LOCATION.—Lat 18<>04'15", long 65°51'39". Owner« P.R. Aqueduct and Sewer Authority. Name: USGS TW-2 or Yabucoa 7. AQUIFER.—Alluvium of Quaternary Age. WELL CHARACTERISTICS.—Drilled observation water-table well, diameter 16 in (0.41 m), cased 0-10 ft (0-3.05 m), diameter 6 in (0.15 m), cased about 0-183 ft (0-55.79 m), perforated 56-81 ft (17.07-24.70 m), 102-123 ft (31.10-37.50 m), 144-181 ft (43.90-55.18 m). Depth 181 ft (55.18 m). DATUM.--Elevation of land-surface datum is about 25 ft (7.62 m) above mean sea level, from topographic map. Measuring point: Top of shelter floor, 4.00 ft (1.22 m) above land-surface. REMARKS.--Recording observation well. PERIOD OF RECORD.—April 25, 1978 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 13.10 ft (3.99 m) below land-surface datum, Dec. 1987; lowest water level recorded, 28.29 ft (8.62 m) below land-surface datum, Sept. 20, 1980. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 20.81 20.78 20.76 20.73 20.69 20.64 20.61 20.58 20.55 20.62 21.59 21.59 21.45 21.31 21.27 21.29 21.29 21.14 20.88 20.48 20.06 19.53 19.07 18.61 18.19 17.95 17.88 17.54 17.21 16.95 16.68 21.59 16.68 NOV 16.44 16.24 16.07 15.92 15.78 15.64 15.51 15.39 15.31 15.25 15.18 15.18 15.20 15.23 15.28 15.40 15.65 15.94 16.21 16.27 16.31 16.37 16.50 16.65 16.79 16.87 16.82 16.82 16.88 16.93 16.93 15.18 DEC 17.07 17.21 17.18 17.27 17.26 17.18 17.11 17.01 16.90 16.78 16.68 16.55 16.44 16.41 16.40 16.41 16.40 16.36 16.29 16.22 16.16 16.09 16.03 16.03 16.04 16.05 16.06 16.14 16.15 16.13 17.27 16.03 JAN 16.05 15.95 15.88 15.86 15.87 15.85 15.82 15.86 15.85 15.75 15.63 15.56 15.50 15.45 15.35 15.26 15.18 15.11 15.10 15.17 15.28 15.42 15.63 15.80 16.06 16.78 17.04 17.08 16.98 16.89 16.83 17.08 15.10 FEB 16.72 16.63 16.61 16.59 16.56 16.53 16.51 16.46 16.41 16.37 16.16 15.94 15.69 15.44 15.21 15.07 14.91 14.68 14.42 14.22 14.13 14.06 14.12 14.24 14.38 14.53 14.69 14.83 16.72 14.06 MAR 14.94 15.06 15.18 15.28 15.40 15.50 15.58 15.63 15.66 15.68 15.72 15.80 16.05 16.32 16.53 16.84 17.22 17.53 17.69 17.75 17.84 18.02 18.15 18.33 18.54 18.75 18.86 18.89 18.92 18.94 18.95 18.95 14.94 APR 18.99 19.00 19.02 19.00 18.86 18.75 18.70 18.70 18.68 18.64 18.63 18.58 18.55 18.55 18.51 18.45 18.39 18.34 18.30 18.28 18.32 18.44 18.67 18.89 19.12 19.33 19.47 19.56 19.67 19.73 19.73 18.28 MAY 19.76 19.76 19.75 19.76 19.80 19.84 19.90 19.96 20.02 20.07 20.10 20.13 20.17 20.22 20.26 20.28 20.33 20.39 20.51 20.70 20.82 20.87 20.88 20.86 20.80 20.75 20.70 20.66 20.61 20.57 20.55 20.88 19.75 JUN 20.53 20.50 20.45 20.39 20.35 20.32 20.26 20.23 20.17 20.07 19.95 19.84 19.83 19.87 19.92 19.95 19.95 19.95 19.91 19.91 19.91 19.90 19.86 19.80 19.77 19.77 19.75 19.73 19.74 19.79 20.53 19.73 JUL 19.73 19.55 19.38 19.17 18.94 18.70 18.49 18.25 18.07 17.90 17.76 17.62 17.51 17.37 17.25 17.14 17.05 17.05 17.15 17.28 17.52 17.76 17.97 18.16 18.32 18.46 18.55 18.68 18.76 18.84 18.90 19.73 17.05 AUQ 18.92 18.95 19.01 19.08 19.14 19.21 19.27 19.37 19.48 19.65 19.79 19.94 20.06 20.17 20.28 20.39 20.49 20.56 20.66 20.74 20.79 20.85 20.92 20.98 21.03 21.06 21.09 21.08 21.02 20.97 20.94 21.09 18.92 SEP 20.92 20.90 20.87 20.86 20.89 20.96 21.07 21.19 21.28 21.34 21.46 21.47 21.48 21.55 21.62 21.73 21.81 21.85 21.89 21.93 21.98 22.08 22.19 22.29 22.39 22.48 22.52 22.53 22.52 22.47 22.53 20.86 WTR YR 1991 MEAN 18.32 LOW 22.53 HIGH 14.06 is m tt IU 14 18 22 on r\ (\\\\s V^ /\ / \ v_\ \J r~ "V ^ *^. J /I/ uv / V -I\fA/\ s\ X /"AV \ ONDJ FMAMJJ ASONDJFMAMJJ ASONDJFMAMJJ AS 1988 1989 1990 1991 • U M M 01609-19) UI*UIMh» WATER LEVEU IN FEET BELOW LAND-SURFACE DATUM l 400 h> I i «J h> Ul I Ol O4 OB O4 N> N> _» 00 Ol 00 OD OB > 10 o z D (O ^ (O (O Ul -J » -J 9\ O Ul » «J Ul Wl «J 09 h» h» 10 00 Ul M U MUM M MM I I I • • • I I I M M »• I I I U) M M M U 10 U M W1 -JO U) U) U) U) U) U) M M M h> M)-> h> 0 h> 09 0 VI ui » M M M U> «fc U 00 -JO -J 09 o 10 cn U) U) Ul Ul U) M M M M Ul \0 V\ 10 UIM h> o cr> tn 09 Ul Ul Ul Ul Ul Ul Ul U M M Ul (HM MM «e o M h> tn Ul M M M O h> 10 en cn<0 «J 0\ 0\ M «0 U Ul Ul Ul M h> a a a 10 <* ~J ~J 0 h> M 00 9\ Wl «J I 09 » 09 09 M Ol 458 GROUND-WATER LEVELS RIO SALINAS TO RIO JACAGUAS BASINS 180002066132200. Local number, HW-TW-01. LOCATION.—Lat 18°00'02', long 66°13'22*. Owneri U.S. Geological Survey, WRD. Name i HW-TW-01. AQUIFER.—Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.—Drilled observation well, diameter 7 in (0.18 m), 0-39.5 ft (0-12.0 m), caved 4 in (0.10 m), 0-38.2 ft (0-11.6 m), screened 32-37 ft (9.75-11.3 m). Depth 39.5 ft (12.0 m). DATUM.--Elevation of land-surface datum is 190 ft (58.0 m) above mean sea level. Measuring pointt Hole on side of 4 in (0.10 m) casing, 2.84 ft (0.87 m) above land-surface datum. Prior October 13, 1988, top of shelter floor, 3.48 ft (1.06 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—April 14, 1988 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 19.34 ft (5.89 m) below land-surface datum, Dec. 18, 1990 to Jan. 26, 1991; lowest water level recorded, 31.24 ft (9.52 m) below land-surface datum, Oct. 1-11, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 31.24 31.24 31.24 31.24 31.24 31.24 31.24 31.24 31.24 31.24 31.21 31.17 31.15 31.14 31.10 31.04 30.99 30.93 30.90 30.86 30.47 29.76 29.25 28.87 28.43 27.70 26.87 26.66 31.24 26.66 NOV DEC 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 JAN 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.34 19.35 19.36 19.37 19.39 19.42 19.42 19.42 19.34 FBB 19.42 19.42 19.42 19.42 19.45 19.45 19.46 19.46 19.46 19.46 19.47 19.47 19.47 19.47 19.47 19.47 19.47 19.48 19.48 19.48 19.48 19.49 19.51 19.53 19.54 19.55 19.60 19.64 19.64 19.42 MAR 19.68 19.77 19.79 19.81 19.82 19.82 19.83 19.88 19.99 20.00 20.02 20.04 20.10 20.13 20.17 20.20 20.23 20.25 20.28 20.31 20.34 20.34 20.34 20.34 20.36 20.36 20.36 20.36 20.36 20.36 20.36 19.68 APR MAY JUN 20.38 20.47 20.51 20.58 20.62 20.64 20.75 20.78 20.89 20.93 21.01 21.06 21.14 21.19 21.23 21.31 21.36 21.42 21.46 21.47 21.60 21.64 21.68 21.78 21.82 21.86 21.91 22.02 22.07 22.10 22.10 20.38 JUL 22.16 22.26 22.32 22.36 22.44 22.51 22.55 22.58 22.70 22.74 22.77 22.82 22.93 22.97 23.01 23.06 23.14 23.19 23.23 23.27 23.36 23.41 23.45 23.49 23.53 23.63 23.67 23.68 23.68 23.70 23.75 23.75 22.16 AUG 23.80 23.86 23.91 23.95 24.00 24.06 24.11 24.15 24.20 24.27 24.32 24.35 24.40 24.48 24.53 24.57 24.61 24.66 24.71 24.76 24.81 24.85 24.85 24.88 24.91 24.95 25.01 25.05 25.08 25.12 25.16 25.16 23.80 SEP 25.21 25.24 25.28 25.32 25.37 25.41 25.44 25.48 25.52 25.56 25.59 25.63 25.68 25.71 25.74 25.79 25.82 25.85 25.90 25.93 25.96 26.00 26.03 26.06 26.09 26.12 26.15 26.19 26.22 26.25 26.25 25.21 " LjQ 15 -£ 24 33 J \ ONDJFMAM 1988 1989 JJASONDJFMAMJJ 1990 ASONDJFMAMJJ 1991 A S WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM ls> tO CO £ tO O oo 00 Z co <- 00 co ~n w O Z o to c_ too -n O Z o to c_ to-• -n 3/ ? HH Ij o» O«O«B<-10t C M * at « H «l«lat0t M HMMMM UlUIUIl^i^ l^i HHHHO OOWJ-J M M M M M si! § oo «e «e «e o U *• W w H HHH HHHHH vototototo tototototo tototototo I I I I I I I I I I I I I I I I I I 0«0« H O H • Mi 9 ft 1 *> s j CD g H-g & n ^ 9 p*0 HUMlVOlH hm- «.g w 3s fty o i Mirt ft U _ V H- ft H-« .-. O M 00 * 88 HC VO Ml ? I H jS?-S? 0 t* w • ft 11 S-fS S!"fr*H. «HS ^K^ 8 H Vlft • • -J.-. f • H- C Ml i* O & «* D 1 ft B *.C Mi 8 MlH ; N & BsB 1*; fi^' ffl ««M& f? SJTo • 12'20". Owner> U.S. Geological Survey, WRD. Namei HW-TW-03. AQUIFER.--Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.—Drilled observation well, diameter 7 in (0.18 m), 0-60 ft (0-18.3 m), cased 4 in (0.10 m), 0-59 ft (0-18.0 n), screened 53-58 ft (16.2-17.7 m). Depth 60 ft (18.3 m) . DATUM.—Elevation of land-surface datum is 271 ft (82.6 m) above mean sea level. Measuring point> Hole on side of 4 in (0.10 M) casing, 3.11 ft (0.95 m) above land-surface datum. Prior October 14, 1989, top of shelter floor, 3.42 ft (1.04 m) above land-surface datum. REMARKS.--Recording observation well. Aquifer test on Dec. 7, 1988 and May 24, 25, 1989. PERIOD OF RECORD.—March 31, 1988 to August 1991, discontinued. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 15.11 ft (4.60 m) below land-surface datum, Dec. 9, 1990| lowest water level recorded, 54.97 ft (16.7 m) below land-surface datum, Oct. 14-22, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 54.90 54.90 54.91 54.91 54.91 54.91 54.92 54.92 54.93 54.93 54.93 54.95 54.96 54.96 54.97 54.97 54.97 54.97 54.97 54.97 54.97 54.97 54.93 54.82 54.61 54.30 53.92 53.34 52.49 51.58 50.70 54.97 50.70 NOV 49.58 48.54 47.33 44.94 40.22 33.38 26.11 21.89 19.78 18.56 17.73 16.95 16.21 15.72 15.39 15.20 15.16 15.13 DEC 49.58 15.13 15.16 15.21 15.31 15.40 15.47 15.55 15.64 15.73 15.80 15.86 15.98 16.07 16.14 16.22 16.34 16.44 16.54 16.65 16.77 16.88 17.02 17.10 17.23 17.23 15.16 JAN 17.35 17.44 17.55 17.66 17.77 17.86 17.95 18.07 18.13 18.13 FBB MAR APR MAY JUN 18.13 17.35 41.80 41.94 42.09 42.23 42.35 42.50 42.50 41.80 JUL 42.65 42.78 42.89 43.01 43.13 43.24 43.34 43.46 43.55 43.67 43.76 43.87 43.98 44.08 44.19 44.30 44.39 44.50 44.61 44.70 44.78 44.87 44.93 45.04 45.13 45.23 45.29 45.35 45.43 45.52 45.70 45.70 42.65 AUQ 45.77 45.84 45.90 45.96 46.03 46.11 46.16 46.22 46.29 46.35 46.42 46.47 46.55 SEP 46.55 45.77 u I -So 15 - 36 I 57 0 19 N 88 D J 19 »••« F 89 -v. M '"•' !•• A »•»• M J J A S 0 N D J 19 F 90 M A M J J A S . 0 ( N *s D w J 19 F 91 M A M > J X J A S 461 GROUND-WATER LEVELS RIO SAUNAS TO RIO JACAGUAS BASINS 18000106*122002 Local number, HN-TW-03C. LOCATION.—Lat 18«00'01", long «6°12'20". Owneri U.S. Geological Survey, WRD. Namei HW-TW-03C. AQUIFER.—Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.—Drilled observation well, diameter 7 in (0.18 m), 0-220 ft (0-67.0 m), cased 4 in (0.10 m), 0-150 ft (0-45.7 m), open hole 150-220 ft (45.7-67.0 m). Depth 220 ft (67.0 a). DATUM.--Elevation of land-surface datum is 270 ft (82.6 m) above mean sea level. Measuring pointi Top of shelter floor, 3.32 ft (1.01 a) above land-surface datum. REMARKS.—Recording observation well. Aquifer test performed during Hay 24, 25, 26, 1989. PERIOD OF RECORD.—December 15, 1988 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 26.29 ft (8.01 m) below land-surface datum, Dec. 15, 1990; lowest water level recorded, 54.60 ft (16.6 m) below land-surface datum, Oct. 3-4, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 C 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 54.55 54.57 54.58 54.56 54.50 54.47 54.37 54.37 54.40 54.40 54.40 54.43 54.4C 54.48 54.4C 54.45 54.38 54.33 54.21 54.12 53.81 53.2< 52.79 52.35 51.82 51.11 50.35 49.56 48.71 47.78 4C.8C 54.58 4C.86 NOV 45.96 45.08 44.2C 43.48 42.83 42.14 41.29 40.37 39.54 38.76 38.03 37.35 36.67 3C.01 35.34 34.63 33.96 33.32 32.76 32.17 31.62 31.09 30.64 30.22 29.83 29.46 29.11 28.82 28.47 28.23 45.96 28.23 DEC 27.97 27.71 27.43 27.29 27.07 26.94 26.82 26.72 26.62 2C.54 26.48 26.44 26.39 26.35 2C.32 26.32 26.32 26.32 26.33 2C.34 26.36 26.36 2C.37 26.41 26.45 JAN FBB MAR APR MAY JUN JUL 27.97 2C.32 47.62 47. C2 47.62 AUO 47.65 47.72 47.78 47.84 47.91 48.00 48.04 48.09 48.13 48.17 48.18 48.16 48.15 48.16 48.18 48.23 48.26 48.31 48.38 48.45 48.49 48.52 48.46 48.51 48.51 48.53 48.55 48.55 48.57 48.58 48.67 48.67 47.65 SEP 48.74 48.78 48.86 48.92 48.99 49.05 49.07 49.09 49.07 49.09 49.08 49.08 49.12 49.18 49.21 49.24 49.25 49.30 49.36 49.40 49.47 49.50 49.49 49.50 49.50 49.50 49.49 49.51 49.56 49.58 49.58 48.74 "I UjQ 36 46 56 OJ F M A M J J 1988 1989 ASONDJFM 1990 AMJJASONDJFMAMJJAS WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM «o OB 00 O £<- i i i i i i i i i i i i 0«00B«J9I ot «J OB • I I I I I >0 i i i i i 90 * i § i »; in in in ui in «O 08 OB OB OB U «0 91 » M in in ui in in OB 91 U O -O 463 GROUND-WATER LEVELS RIO SALIKAS TO RIO JACAOUAS BASINS 180000066125200 Local number, HW-TW-04. LOCATION.--Lat 18«00'00", long 66°12'52". Owneri U.S. Geological Survey, WRD. NaiMt HW-TW-04. AQUIFER.—Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.—Drilled observation well, diameter 7 in (0.18 m), 0-48.5 Ct (0-14.8 m) cased 4 in (0.10 m), 0-48 ft (0-14.6 m), screened 42-47 Ct (12.8-14.3 m). Depth 48.5 Ct (14.8 m). DATUM.—Elevation oC land-surCace datum is 177 Ct (53.9 m) above Bean sea level. Measuring points Hole on side oC casing, 2.69 Ct (0.82 m) above land-surface datum. Prior October 13, 1989 top oC shelter Cloor, 3.50 Ct (1.07 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.—April 5, 1988 to August 1991, discontinued. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 18.39 Ct (5.60 m) below land-surCace datum, Apr. 5, 1988; lowest water level recorded, 29.40 Ct (8.96 m) below land-surCace datum, Sept. 5, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUQ —— —— — ___ — ___ — ___ — ___ 21.71 21.72 21.75 21.77 21.80 21.81 21.86 —— 21.86 21.71 21.87 21.89 21.92 21.92 21.94 21.95 21.97 21.99 22.01 22.02 22.04 22.07 22.09 22.12 22.14 22.17 22.19 22.19 22.21 22.21 22.22 22.22 22.23 22.23 22.23 22.25 22.25 22.27 22.28 22.30 22.34 22.34 21.87 22.34 22.35 22.35 22.36 22.38 22.41 22.46 22.47 22.51 22.52 22.55 22.59 22.62 22.64 22.68 22.72 22.74 22.77 22.78 22.80 22.81 22.83 —— 22.83 22.34 SEP -£ 24 30 JN\ -J ONOJFMAHJJ 1988 1989 AS ONOJ FMAM 1990 JJ ASONDJ FMAMJJ 1991 A S 464 GROUND-WATER LEVELS RIO SAUNAS TO RIO JACAGDAS BASINS 175947066130601 Local number, HW-TW-05B. LOCATION. —Lat 17»59'47-, long 66<>13'06-. Owneri U.S. Geological Survey, WRD. Namei HW-TW-05B. AQUIFER.—Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.--Drilled observation well, diameter 7 in (0.18 m), 0-52 ft (0-15.8 m), cased 4 in (0.10 m), 0-51 ft (0-15.5 m), screened 41-46 ft (12.5-14.0 m). Depth 52 ft (15.8 m). DATUM.—Elevation of land-surface datum is 145 ft (44.2 m) above mean sea level. Measuring pointt Hole on side of casing, 3.00 ft (0.91 m) above land-surface datum. Prior October 13, 1989 top of shelter floor, 3.47 ft (1.06 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—April 13, 1988 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 9.40 ft (2.86 m) below land-surface datum, Aug. 25, 1988; lowest water level recorded, 22.14 ft (6.75 m) below land-surface datum, Sept. 5, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT NOV DEC JAN FEB MAR APR MAY JUN 10.95 10.99 11.08 11.12 11.16 11.23 11.28 11.34 11.41 11.45 11.45 10.95 14.26 14.27 14.28 14.29 14.30 14.31 14.31 14.26 JUL 14.27 14.23 14.21 14.19 14.17 14.17 14.17 14.19 14.20 14.22 14.23 14.25 14.29 14.30 14.32 14.24 13.92 13.81 13.73 13.69 13.65 13.64 13.62 13.62 13.61 13.63 13.63 13.65 13.67 13.69 13.70 14.32 13.61 AUQ 13.72 13.76 13.79 13.83 13.85 13.90 13.94 13.98 14.01 14.06 14.10 14.14 14.17 14.20 14.17 14.14 14.10 14.08 14.08 14.08 14.09 14.09 12.81 12.72 12.65 12.62 12.60 12.58 12.56 12.55 12.56 14.20 12.55 SEP 12.60 12.60 12.62 12.66 12.74 12.80 12.86 12.92 12.98 12.97 12.98 13.01 13.06 13.10 13.15 13.19 13.25 13.24 13.23 13.23 13.25 13.26 13.15 12.99 12.96 12.95 12.95 12.96 13.00 13.00 13.26 12.60 sf x 24 0 N D J FMAMJ 1988 1989 ASONOJ FMAM 1990 JJ ASONDJ FMAM 1991 J J A S 465 GROUND-WATER LEVELS RIO SALINAS TO RIO JACAGUAS BASINS 180006066123700 Local number, HW-TW-07. LOCATION.—Lat 18«00'06", long 66°12'37-. Owneri U.S. Oeological Survey, WRD. Namei HW-TW-07. AQUIFER.--Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.—Drilled observation trail, diameter 7 in (0.18 m), 0-88 ft (0-26.8 m), cased 4 in (0.10 m), 0-82 ft (0-25.0 m), screened 69-77 ft (21.0-29.5 m). Depth 88 ft (26.8 m). DATUM.--Elevation of land-surface datum is 240 ft (73.2 m) above mean sea level. Measuring points Hole on side of casing, 2.99 ft (0.91 m) above land-surface datum. Prior October 13, 1988 top of shelter floor, 3.48 ft (1.06 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—April 1988 to August 1991, discontinued. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 18.04 ft (5.50 m) below land-surface datum, Dec. 16-18, 1990; lowest water level recorded, 38.36 ft (11.7 m) below land-surface datum, Oct. 1-7, 1990 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 38.35 38.35 38.35 38.35 38.35 38.36 38.35 38.33 38.32 38.31 38.31 38.26 38.20 38.15 38.09 37.95 37.83 37.72 37.56 37.20 35.27 32.06 31.07 30.51 29.79 27.03 24.63 23.66 23.15 22.83 22.57 38.36 22.57 22.37 22.17 22.03 21.91 21.82 21.69 21.59 21.38 21.25 21.14 21.03 20.94 20.84 20.74 20.66 20.53 20.42 20.30 20.20 20.06 19.91 19.78 19.66 19.53 19.40 19.26 19.18 19.03 18.92 18.82 —— 22.37 18.82 18.73 18.64 18.55 18.48 18.40 18.34 18.28 18.26 18.22 18.18 18.15 18.14 18.11 18.09 18.07 18.07 18.06 18.07 18.13 18.17 18.19 18.24 18.29 18.34 18.40 18.48 18.55 18.64 18.72 18.77 18.84 18.84 18.06 18.90 18.96 19.03 19.10 19.17 19.26 19.34 19.42 19.52 19.60 19.68 19.76 19.84 19.92 20.01 20.08 20.18 20.26 20.35 20.39 20.50 20.58 20.68 20.77 20.81 20.94 20.98 21.06 21.17 21.21 21.34 21.34 18.90 21.38 21.44 21.55 21.59 21.64 21.75 21.76 21.77 21.79 21.82 21.94 21.96 21.97 21.98 22.02 22.09 22.16 22.19 22.22 22.27 22.36 22.39 22.43 22.54 22.57 22.61 22.75 22.79 —— —— —— 22.79 21.38 22.82 22.93 22.97 23.00 23.06 23.15 23.17 23.20 23.27 23.34 23.38 23.41 23.57 23.60 23.67 23.77 23.98 —— _ _ —— _ _ —— 23.98 22.82 28.32 28.35 28.40 28.44 28.49 28.55 28.59 28.63 28.68 28.72 28.76 28.82 28.86 28.90 28.93 28.98 29.02 29.06 29.12 29.16 29.18 29.19 29.29 29.32 29.35 29.38 —— 29.38 28.32 29.42 29.47 29.50 29.53 29.55 29.58 29.62 29.68 29.73 29.77 29.82 29.85 29.89 29.93 29.99 30.03 30.05 30.08 30.11 30.13 30.15 30.18 30.21 30.27 30.31 30.33 30.34 30.34 30.37 30.38 30.56 30.56 29.42 30.59 30.64 30.68 30.72 30.77 30.83 30.87 30.91 30.97 31.03 31.07 31.11 31.15 31.20 31.26 31.29 31.33 31.36 31.38 31.40 31.42 31.43 —— ___ —— —— 31.43 30.59 ONDJFMAMJJ 1988 1989 ASONDJ FM 1990 A M J J ASONDJ FMAM 1991 J J A S 466 OROOND-WATBR LEVELS RIO SALINAS TO RIO JACAGUAS BASINS 175939066121400 Local number, HW-TW-08. LOCATION. —Lat 17°59'39 B , long 66»12'14'. Owners U.S. Geological Survey, WRD. Namei HW-TW-08. AQOIFER.—Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.—Drilled observation well, diameter 7 in (0.18 m), 0-49 ft (0-14.9 m ), cased 4 in (0.10 m), 0-49 ft (0-14.9 m), acreened 43-48 ft (13.1-14.6 m). Depth 49 ft (14.9 m). DATUM.—Elevation of land-surface datum is 172 ft (52.4 m) above mean sea level. Measuring point: Hole on Bide of casing, 2.83 ft (0.86 m) above land-surface datum. Prior October 7, 1988 top of shelter floor, 3.55 ft (1.08 m) above land-surface datum. REMARKS.--Recording obiervation well. PERIOD OF RECORD.—April 13, 1988 to AuguBt 1991, discontinued. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 6.23 ft (1.90 m) below land-surface datum, Dec. 5, 1990; lowest water level recorded, 42.43 ft (12.9 m) below land-surface datum, Oct. 3-6, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 42.42 42.42 42.42 42.43 42.43 42.42 42.35 42.24 42.15 42.07 42.01 41.91 41.73 41.52 41.33 41.01 40.70 40.39 40.01 39.53 38.48 34.14 31.32 29.94 28.95 26.61 22.23 —— —— —— 42.43 22.23 —— 9.79 9.47 9.18 8.89 8.62 8.36 8.14 7.93 7.77 7.63 7.48 7.37 7.33 7.26 7.20 7.14 7.08 7.05 6.44 6.39 6.34 —— 9.79 6.34 6.29 6.26 6.27 6.27 6.26 6.26 6.30 6.34 6.38 6.40 6.44 6.50 6.53 6.59 6.63 6.71 6.76 6.80 6.87 6.93 6.98 7.04 7.11 7.19 7.27 7.35 7.44 7.51 7.60 7.66 7.74 7.74 6.26 7.81 7.88 7.96 8.04 8.12 8.19 8.26 8.34 8.42 8.50 8.57 8.63 8.71 8.79 8.84 8.95 9.03 9.11 9.19 9.25 9.32 9.41 9.49 9.56 9.64 9.72 9.78 9.86 9.96 10.03 10.12 10.12 7.81 10.20 10.27 10.35 10.43 10.50 10.59 10.66 10.73 10.81 10.90 11.00 11.08 11.16 11.24 11.33 11.41 11.49 11.57 11.65 11.75 11.82 11.92 12.01 12.09 12.17 12.26 12.35 12.45 —— —— 12.45 10.20 12.53 12.62 12.70 12.80 12.90 12.98 13.08 13.17 13.27 13.37 13.48 13.59 13.68 13.79 13.89 13.98 14.08 14.21 14.31 14.44 14.54 14.66 14.75 14.85 14.96 15.07 15.18 15.28 15.40 15.51 15.64 15.64 12.53 15.74 15.82 15.94 16.05 16.16 16.25 16.36 16.48 16.59 16.70 16.79 16.90 17.00 17.12 17.24 17.35 17.42 17.52 17.64 17.74 17.83 17.94 18.05 18.16 18.24 18.35 18.44 18.56 18.66 18.77 —— 18.77 15.74 18.86 18.95 19.05 19.16 19.26 19.35 19.44 19.54 19.64 19.76 19.85 19.96 20.06 20.15 20.25 20.34 20.44 20.53 20.62 20.65 20.80 20.82 20.84 —— 20.84 18.86 —— —— —— —— —— —— 24.34 24.43 24.55 24.65 24.76 24.88 —— 24.88 24.34 24.99 25.10 25.21 25.32 25.42 25.53 25.64 25.75 25.88 25.98 26.08 26.19 26.30 26.42 26.51 26.62 26.71 26.83 26.94 27.05 27.15 27.25 27.35 27.45 27.56 27.65 27.76 27.85 27.96 28.07 28.19 28.19 24.99 28.27 28.38 28.45 28.46 —— —— —— 30.57 30.68 30.76 30.86 30.95 31.04 31.15 31.23 31.35 31.35 28.27 31.45 31.54 31.64 31.73 31.86 31.95 32.05 32.14 32.22 32.33 32.40 32.48 32.56 32.65 32.73 32.81 32.90 32.97 33.07 33.15 33.24 33.30 33.39 33.49 33.55 33.64 33.71 33.79 33.89 33.96 33.96 31.45 S\ S. \ S, 0 N D J FMAM 1988 1989 JJASONOJFMAMJJ 1990 ASONDJFMAMJJ 1991 A S GROUND-WATER LEVELS RIO SAUNAS TO RIO JACAGUAS BASINS 467 175950066125200 Local number, HW-TW-10. LOCATION.—Lat 17«59'50", long 66«12'52". Owneri U.S. Geological Survey, WRD. NaiMi HW-TW-10. AQUIFER.--Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.—Drilled observation well, diameter 7 in (0.18 n), 0-55 ft (0-16.8 n), cased 4 in (0.10 n), 0-54 ft (0-16.4 m), screened 48-53 ft (14.6-16.2 n). Depth 55 ft (16.8 m) . DATUM.—Elevation of land-surface datum is 159 ft (48.5 m) above Bean sea level. Measuring pointi Hole on side of casing, 2.98 ft (0.91 n) above land-surface datum. Prior October 14, 1988 top of shelter floor, 3.61 ft (1.10 n) above land-surface datum. REMARKS.--Recording observation well. Pumping test on Dec. 8, 1988, May 22, 1989, and July 13, 1989. PERIOD OF RECORD.—April 5, 1988 to August 1991, discontinued. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 13.40 ft (4.08 m) below land-surface datum, Nov. 19, 1990; lowest water level recorded, 30.76 ft (9.38 m) below land-surface datum, Sept. 5, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 30.38 30.36 30.35 30.32 30.32 30.21 30.04 29.98 29.95 29.92 29.80 29.48 29.35 29.28 29.08 28.77 28.67 28.54 28.28 28.06 26.95 25.33 24.64 24.30 23.57 22.24 20.92 20.08 19.40 18.84 18.14 30.38 18.14 MOV 17.65 17.17 16.76 16.36 15.95 15.52 15.21 14.93 14.72 14.41 14.24 14.04 13.90 13.80 13.70 13.59 13.53 13.46 13.42 DEC JAN FEB MAR APR MAY JUN 17.65 13.42 23.35 23.35 23.40 23.44 23.46 23.49 23.49 23.35 JUL 23.51 23.54 23.56 23.57 23.58 23.60 23.63 23.65 23.67 23.70 23.73 23.75 23.77 23.80 23.83 23.89 23.89 23.89 23.89 23.91 23.92 23.93 23.94 23.95 23.98 23.99 24.00 24.02 24.04 24.06 24.10 24.10 23.51 AUG 24.09 24.11 24.11 24.15 24.17 24.22 24.25 24.26 24.28 24.31 24.34 24.35 24.39 24.42 24.45 24.46 24.47 24.48 24.48 24.49 24.49 24.48 SEP 24.49 24.09 b I 31 ONOJ FMAMJJ 1988 1989 ASONDJ FMAMJJ 1990 ASONDJFMAMJJ 1991 A S 468 GROUND-WATER LEVELS RIO SAUNAS TO RIO JACAGUAS BASINS 180012066125500 Local number, HW-TW-11. LOCATION.—Lat 18*00'12", long 66«12'55«. Owneri U.S. Geological Survey, WRD. Namei HW-TW-11. AQUIFER.—Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.—Drilled observation well, diameter 7 in (0.18 m), 0-94.9 ft (0-28.9 m), cased 4 in (0.10 m), 0-94 ft (0-28.6 m), screened 79-89 ft (24.1-27.1 m). Depth 94.9 ft (28.9 m). DATUM.—Elevation of land-surface datum is 240 ft (73.2 m) above mean sea level. Measuring pointi Hole on side of casing, 3.04 ft (0.96 m) above land-surface datum. Prior October 13, 1988 top of shelter floor, 3.74 ft (1.14 m) above land-surface datum. REMARKS.—Recording observation well. Aquifer test performed on Dec. 9, 1988 and Hay 23, 1989. PERIOD OF RECORD.—April 14, 1988 to August 1991, discontinued. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 55.45 ft (16.9 m) below land-surface datum, Dec. 31, 1990, Jan. 1, 1991; lowest water level recorded, 76.20 ft (23.2 m) below land-surface datum, Oct. 16-22, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 76.09 76.10 76.11 76.12 76.13 76.13 76.14 76.14 76.15 76.15 76.16 76.16 76.17 76.19 76.19 76.20 76.20 76.20 76.20 76.20 76.20 76.20 76.10 75.97 75.79 75.59 75.24 74.55 73.64 72.70 71.75 76.20 71.75 NOV 70.86 70.00 69.12 68.33 67.55 66.84 66.13 65.46 64.85 64.25 63.68 63.12 62.59 62.09 61.61 61.17 60.74 60.35 60.02 59.67 59.32 59.02 58.75 58.49 58.23 58.01 57.79 57.60 57.40 57.24 70.86 57.24 DEC 57.07 56.92 56.78 56.67 56.53 56.41 56.31 56.21 56.12 56.03 55.96 55.92 55.85 55.81 55.75 55.71 55.67 55.62 55.60 55.58 55.55 55.52 55.50 55.48 55.49 55.48 55.47 55.46 55.47 55.46 55.46 57.07 55.46 JAN 55.46 55.46 55.47 55.48 55.50 55.51 55.52 55.54 55.56 55.58 55.60 55.62 55.63 55.66 55.68 55.70 55.73 55.76 55.78 55.79 55.81 55.85 55.89 55.93 55.95 55.98 56.00 56.04 56.07 56.09 56.12 56.12 55.46 FBB 56.15 56.18 56.19 56.21 56.25 56.28 56.31 56.34 56.38 56.40 56.45 56.46 56.49 56.52 56.56 56.59 56.62 56.65 56.68 56.72 56.74 56.77 56.80 56.82 56.85 56.87 56.93 56.97 56.97 56.15 MAR 57.00 57.02 57.05 57.08 57.11 57.15 57.20 57.24 57.27 57.29 57.32 57.37 57.41 57.46 57.50 57.53 57.58 57.62 57.66 57.70 57.74 57.77 57.81 57.88 57.94 57.98 58.02 58.06 58.10 58.17 58.21 58.21 57.00 APR 58.23 58.28 58.34 58.39 58.44 58.48 58.53 58.59 58.63 58.68 58.72 58.78 58.82 58.85 58.91 58.96 59.00 59.03 59.09 59.14 59.19 59.23 59.29 59.34 59.37 59.42 59.47 59.52 59.57 59.62 59.62 58.23 MAY 59.67 59.71 59.75 59.81 59.86 59.93 59.97 60.00 60.04 60.09 60.13 60.17 60.22 60.27 60.30 60.34 60.37 60.41 60.44 60.48 60.54 60.60 60.65 60.69 60.73 60.76 60.80 60.83 60.85 60.90 60.95 60.95 59.67 JUN 61.00 61.04 61.07 61.12 61.15 61.19 61.25 61.29 61.34 61.38 61.42 61.45 61.51 61.56 61.60 61.64 61.69 61.73 61.77 61.81 61.85 61.89 61.94 62.01 62.02 62.05 62.10 62.14 62.18 62.24 62.24 61.00 JUL 62.29 62.33 62.36 62.39 62.44 62.49 62.53 62.57 62.62 62.66 62.71 62.74 62.79 62.83 62.89 62.94 62.97 63.02 63.05 63.11 63.13 63.17 63.21 63.23 63.29 63.33 63.37 63.41 63.46 63.51 63.58 63.59 62.29 AUG 63.61 63.65 63.68 63.72 63.77 63.81 63.85 63.88 63.92 63.97 64.01 64.05 64.09 64.13 64.20 64.23 64.29 64.33 64.37 64.41 64.47 64.50 SEP 64.50 63.61 66 77 ONDJ FMAM 1988 1989 J J A S ONDJ FMAM 1990 J J A S 0 N 0 J F 1991 M A M J J A 469 GROUND-WATER LEVELS RIO SAUNAS TO RIO JACAGUAS BASINS 180012066125502 Local number, HW-TW-11C. LOCATION.—Lat 18000'12-, long 66°12'55-. Ownert U.S. Geological Survey, WRD. Namei HW-TW-llC. AQDIFER.--Fractured, volcanic rock, water-table aquifer. NELL CHARACTERISTICS.—Drilled observation trail, diameter 6 in (0.15 m), 0-95.0 ft (0-29.0 m) diameter 2.9 in (0.07m), 95-200 ft (29.0-61.0 m ), cased 4 in (0.10 m), 0-95 ft (0-29.0 m), open hole 95-200 ft (29.0-61.0 m). Depth 200 ft (61.0 m). DATUM.—Elevation of land-surface datum is 240 ft (73.2 m) above mean sea level. Measuring pointi Top of shelter floor, 3.56 ft (1.08 m) above land-surface datum. REMARKS.—Recording observation well. Pumping test on May 23, 24, 1989. PERIOD OF RECORD.—December 1988 to August 1991, discontinued. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 60.19 ft (18.3 m) below land-surface datum, June 24, 1991| lowest water level recorded, 74.27 ft (22.6 m) below land-surface datum, Oct. 2, 1990. HATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HI OH OCT 74.25 74.28 NOV DEC JAN FEB MAR APR MAY JUN JUL AUQ 74.28 74.25 --- ___ — _ _ —— — ___ — ___ ___ 60.25 60.25 60.28 60.34 60.35 60.38 60.38 —— 60.38 60.25 60.42 60.48 60.53 60.56 60.61 60.66 60.74 60.80 60.86 60.94 60.97 61.01 61.03 61.04 61.05 61.04 61.13 61.17 61.21 61.28 61.33 61.38 61.44 61.50 61.55 61.58 61.60 61.62 61.66 61.67 61.73 61.73 60.42 61.75 61.82 61.88 61.93 61.98 62.06 62.12 62.18 62.24 62.30 62.33 62.35 62.35 62.38 62.42 62.49 62.54 62.59 62.65 62.74 62.79 62.83 ___ ___ —— 62.83 61.75 SEP 32 eo «§ UJQ SB 5 !fc 68 76 Xs DJFMAMJJ 19881989 ASONDJFMAMJJ 1990 ASO N D J F M A M 1991 J J A S 470 GROUND-WATER LEVELS RIO SAUNAS TO RIO JACAOOAS BASINS 175957066123400 Local number, HW-TW-13. LOCATION.—Lat 17°59'57", long 66°12'34«. Owneri U.S. Geological Survey, WRD. Name i HW-TW-13. AQUIFER.—Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.—Drilled observation well, diameter 7 in (0.18 m), 0-69 ft (0-21.0 m), cased 4 in (0.10 m), 0-69 ft (0-21.0 m), screened 4.0-69 ft (1.22-21.0 m). Depth 69 ft (21.0 m). DATUM.—Elevation of land-surface datum is 203 ft (61.9 m) above mean sea level. Measuring points Hole on side of casing, 2.33 ft (0.71 m) above land-surface datum. Prior October 14, 1988, top of shelter floor, 3.47 ft (1.06 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—April 14, 1988 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 34.39 ft (10.5 m) below land-surface datum, Oct. 27, 1990; lowest water level recorded, 46.95 ft (14.3 m) below land-surface datum, June 8, 1988. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 46.00 45.97 45.87 45.79 45.75 45.75 45.56 45.17 45.09 45.08 45.03 44.71 44.69 44.64 44.55 44.49 44.53 44.49 44.48 44.49 39.06 40.03 41.43 41.76 40.63 36.49 34.53 —— —— 46.00 34.53 NOV DEC JAN FBB MAR APR MAY JUN JUL AUQ SEP 45.82 45.82 45.83 45.83 45.83 45.83 45.82 45.82 45.82 45.82 45.82 45.82 45.82 45.82 45.82 45.82 45.83 45.82 45.82 45.82 45.83 45.84 45.87 45.86 45.80 45.74 45.73 45.73 45.73 45.72 45.74 45.87 45.72 45.75 45.76 45.77 45.78 45.78 45.79 45.80 45.80 45.81 45.81 45.81 45.81 45.81 45.82 45.82 45.82 45.82 45.82 45.82 45.82 45.82 45.82 45.81 45.82 45.82 45.82 45.82 45.82 45.82 45.82 —— 45.82 45.75 Lo B2 34 48 ONDJFMAMJJ 1988 1989 ASONDJFMAMJJ 1990 ASONDJFMAMJJ 1991 A S 471 GROUND-WATER LEVELS RIO SALINAS TO RIO JACAGUAS BASINS 175946066102000 Local number, HW-TW-14. LOCATION.—Lat 17«59'46-, long 66«10'^0". Owners U.S. Geological Survey, WRD. Names HW-TW-14. AQDIFBR.—Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.—Drilled observation well, diameter 7 in (0.18 m), 0-79 ft (0-24.4 m), cased 4 in (0.10 m), 0-79 ft (0-24.1 m), screened 71-78 ft (21.6-23.8 m). Depth 79 ft (24.1 m). DATUM.—Elevation of land-surface datum is 205 ft (62.5 m) above mean sea level. Measuring points Hole on side of casing, 3.02 ft (0.92 m) above land-surface datum. Prior October 7, 1988, top of shelter floor, 3.67 ft (1.12 m) above land-surface datum. REMARKS.--Recording Observation well. Well dry at 73.56 ft (22.42 m). PERIOD OF RBCORD.—December 1987 to current year. EXTREMES FOR PERIOD OF RBCORD.--Highest water level measured, 41.1 ft (12.5 m) below land-surface datum, Dec. 17, 1987; lowest water level recorded, 75.35 ft (23.0 m) below land-surface datum, Oct. 2, 1989. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.54 73.55 73.08 71.38 70.29 69.28 67.83 65.83 63.59 61.34 59.14 56.88 73.55 56.88 54.80 52.99 —— ___ —— ___ —— ___ —— ___ —— —— 54.80 52.99 JUN JUL AUG SEP --- —— ___ 69.06 69.16 69.27 69.37 69.48 69.57 69.67 69.77 69.86 69.96 70.06 70.16 70.25 70.35 70.46 70.55 70.67 70.67 69.06 70.77 70.87 70.97 71.06 71.15 71.25 71.33 71.42 71.50 71.59 71.68 71.73 71.81 71.87 71.93 71.97 72.02 72.02 72.03 72.04 72.04 72.05 72.05 72.05 72.05 72.05 72.05 72.05 72.05 72.05 72.05 72.05 70.77 72.05 72.05 72.05 72.05 72.05 72.05 72.05 72.05 72.06 72.06 72.07 72.18 72.25 72.32 72.40 72.45 72.51 72.58 72.65 72.72 72.80 72.87 72.96 73.06 73.16 73.29 73.39 73.46 73.53 73.59 73.59 73.59 72.05 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.60 73.61 73.61 73.61 —— 73.61 73.60 12 »? 76 \ \ F M A M J J ASONDJ FMAMJJ ASONDJ FMAMJJ AS 1989 1990 1991 472 GRODND-WATER LEVELS RIO SALIHAS TO RIO JACAOUAS BASINS 175955066103000 Local number, HW-TW-15. LOCATION.—Lat 17°59'55", long 66»10'30". Owneri U.S. Geological Survey, WRD. Names HW-TW-15. AQUIFER.—Fractured, volcanic rock, water-table aquifer. NELL CHARACTERISTICS.—Drilled observation well, diameter 7 in (0.18 B), 0-85 ft (0-25.9 m), cased 4 in (0.10 m), 0-85 ft (0-25.9 B), screened 70-80 ft (21.3-24.4 B) . Depth 85 ft (25.9 m). DATUM.—Elevation of land-surface datum is 269 ft (82.0 B) above mean sea level. Measuring pointt Hole on side of casing, 3.12 ft (0.95 m) above land-surface datum. Prior October 7, 1988, top of shelter floor, 3.60 ft (1.10 B) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—March 30, 1988 to November 1990, discontinued. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 36.20 ft (11.0 B) below land-surface datum. Mar. 30, 1988; lowest water level recorded, 64.70 ft (19.7 B) below land-surface datum, Oct. 20, 21, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 64.52 64.52 64.53 64.54 64.56 64.58 64.58 64.59 64.60 64.60 64.62 64.62 64.63 64.65 64.66 64.66 64.68 64.68 64.69 64.70 64.70 64.31 64.04 63.74 63.29 62.36 61.14 59.73 58.27 56.84 55.38 64.70 55.38 NOV 53.78 51.89 49.74 47.32 44.89 42.56 40.46 38.44 36.74 DEC JAN FBB APR MAY JUN OUL AUG SEP 53.78 36.74 ONDJFMAMJJ 1988 1989 ASONDJFMAMJJ 1990 ASONDJFMAMJJAS 1991 4T3 GROUND-WATER LEVELS RIO SALIKAS TO RIO JACAGUAS BASINS 180206066135500. Local number, RM # S. LOCATION.—Lat 18°02'06', long 66°13'S5'. Owneri U.S. Geological Survey, WRD. Namei RM # 5. AQUIFER.—Quaternary alluvium. NELL CHARACTERISTICS.—Drilled observation water-table well, diameter 4 in (0.10 m), cased 4 in (0.10 m), 0-34 ft (0-10.4 m), screened 24-34 ft (7.32-10.7 m). Depth 34 ft (10.4 m). DATUM.--Elevation of land-surface datum is 276.35 ft (84.2 m) above mean sea level. Measuring pointi Top of shelter floor, 3.28 ft (1.0 m) above land-surface datum. REMARKS.—Recording observation well. Pumping teat performed during February 2, 7, 1990. PERIOD OF RECORD.—March 9, 1989 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 8.15 ft (2.48 m) below land-surface datum, Oct. 26, 1990; lowest water level recorded, 19.87 ft (6.06 m) below land-surface datum, June 14, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 10.62 10.88 11.06 11.21 11.33 11.44 11.49 11.58 11.34 10.63 10.89 11.05 10.57 10.84 10.87 11.00 10.89 11.09 10.41 10.76 8.75 9.23 9.40 9.63 9.05 .46 .61 .80 .08 .32 .40 11.58 8.46 9.67 9.87 10.04 10.19 10.25 10.37 10.47 10.57 10.64 10.71 10.77 10.81 10.85 10.89 10.94 10.98 11.01 11.04 11.06 11.09 11.10 11.13 11.17 11.20 11.23 11.23 11.25 11.25 11.28 11.29 11.29 9.67 11.29 11.32 11.33 11.33 11.35 11.36 11.38 11.39 11.40 11.41 11.41 11.38 11.42 11.35 11.41 11.44 11.45 11.46 11.48 11.48 11.49 11.51 11.52 11.53 11.53 11.54 11.55 11.56 11.53 11.49 11.47 11.56 11.29 11.44 11.46 11.51 11.53 11.55 11.57 11.57 11.57 11.51 11.54 11.55 11.55 11.57 11.57 11.58 11.56 11.57 11.58 11.60 11.60 11.61 11.61 11.62 11.62 11.63 11.64 11.65 11.66 11.66 11.68 11.74 11.74 11.44 11.71 11.71 11.73 11.73 11.74 11.46 11.44 11.65 11.74 11.78 11.55 11.75 11.45 11.67 11.77 11.82 11.84 11.85 11.81 11.84 11.85 11.85 11.86 11.86 11.84 11.84 11.85 11.84 —— —— 11.86 11.44 11.82 11.82 11.82 11.78 11.74 11.69 11.69 11.69 11.67 11.68 11.69 11.68 11.68 11.67 11.67 11.67 11.67 11.68 11.77 11.79 11.81 11.83 11.79 11.82 11.86 11.88 11.78 11.85 11.89 11.93 11.94 11.94 11.67 11.97 11.98 11.97 12.01 12.02 12.04 12.04 12.05 12.05 12.05 12.08 12.07 12.07 12.09 12.10 12.09 12.11 12.11 12.12 12.12 12.12 12.11 12.12 12.13 12.12 12.14 12.14 12.16 12.16 12.17 12.17 11.97 12.19 12.18 12.18 12.20 12.20 12.22 12.24 12.24 12.25 12.27 12.28 12.25 12.26 12.23 12.25 12.25 12.25 12.23 12.25 12.28 12.28 12.29 12.31 12.39 12.38 12.29 12.33 12.42 12.44 12.43 12.44 12.44 12.18 12.43 12.35 12.35 12.46 12.53 12.55 12.36 12.35 12.50 12.62 12.77 12.70 12.50 12.58 12.72 12.84 12.98 13.13 13.27 13.36 13.42 13.48 13.55 13.63 13.74 13.85 13.98 14.12 14.24 14.33 14.33 12.35 12.25 12.23 12.24 12.30 12.38 12.42 12.52 12.60 12.63 12.73 12.86 12.99 13.14 13.33 13.54 12.39 11.93 11.97 12.00 12.01 12.03 12.07 12.12 12.19 12.27 12.39 12.26 12.33 12.33 12.12 12.12 13.54 11.93 12.26 12.64 12.91 13.15 13.38 13.63 13.88 14.13 14.34 14.59 14.83 14.99 15.14 15.27 15.00 14.55 14.14 14.12 14.17 14.31 14.37 14.29 12.35 12.27 12.26 12.26 12.28 12.16 12.13 12.14 12.20 15.27 12.13 12.40 12.66 12.93 13.18 13.50 13.76 13.99 14.16 14.35 14.54 14.72 14.91 15.06 15.19 15.28 15.38 15.45 13.46 12.77 12.51 12.29 12.29 12.10 11.97 11.97 12.01 12.03 12.08 12.05 11.86 — — _ 15.45 11.86 WTR YR 1991 MEAN 12.03 LOW 15.45 HIGH 8.46 — \ S "\ \ SA,JI ~-~h. "">^ A ^\' "J 11r Af v V, *• • — ^^^\i , MAMJ J ASONOJ FMAMJ J ASONOJ FMAMJ J AS 1989 1990 1991 22 474 GROUND-WATER LEVELS RIO SALINAS TO RIO JACAOUAS BASINS 180104066152300. Local number, RM * 10. LOCATION.--Lat 18°01'04", long 66°15'23". Owners U.S. Geological Survey, WRD. Names RM * 10. AQUIFER.--Quaternary alluvium. WELL CHARACTERISTICS.—Drilled observation water-table well, diameter 4 in (0.10 m), cased 4 in (0.10 m), 0-37 ft (0-11.3 m), screened 27-37 ft (8.23-11.3 m). Depth 37 ft (11.3 m). * DATUM.—Elevation of land-surface datum is 164.13 ft (50.0 m) above mean sea level, from leveling survey. Measuring points Top of shelter floor, 3.62 ft (1.10 m) above land-surface datum. REMARKS.—Recording observation well. Pumping test performed on February 8, 1990. PERIOD OF RECORD.—March 13, 1989 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 18.00 ft (5.49 m) below land-surface datum, Nov. 9, 1990; lowest water level recorded, 35.56 ft (10.8 m) below land-surface datum, Aug. 28-29, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 21.93 20.56 18.80 18.76 18.75 18.75 18.72 18.72 21.93 18.72 NOV 18.72 18.71 18.70 18.53 18.25 18.19 18.20 18.23 18.01 18.01 18.01 18.02 18.02 18.02 18.02 18.02 18.02 18.02 18.02 18.02 18.02 18.02 18.02 18.02 18.03 18.03 18.03 18.03 18.03 18.03 18.72 18.01 DEC 18.03 18.03 18.03 18.03 18.03 18.03 18.07 18.13 18.18 18.23 18.09 JAN FBB 18.23 18.03 21.10 21.10 21.10 21.13 21.15 21.17 21.19 21.23 21.26 21.26 21.10 MAR 21.33 21.36 21.41 21.46 21.50 21.50 21.45 21.45 21.52 21.65 21.73 21.84 21.94 22.06 22.18 22.32 22.48 22.66 22.80 22.97 23.11 23.30 23.43 23.56 23.68 23.80 23.87 23.91 23.96 24.00 24.06 24.06 21.33 APR 24.14 24.29 24.41 24.57 24.68 24.78 24.87 25.03 25.12 25.21 25.32 25.45 25.55 25.68 25.77 25.86 25.93 26.01 26.08 26.19 26.26 26.32 26.41 26.47 26.53 26.61 26.71 26.77 26.83 26.91 26.91 24.14 MAY 27.00 27.06 27.13 27.20 27.28 27.34 27.40 27.48 27.57 27.64 27.68 27.70 27.71 27.76 27.82 27.89 27.96 28.02 28.06 28.12 28.21 28.28 28.34 28.37 28.45 28.48 28.52 28.56 28.63 28.70 28.72 28.72 27.00 OUN 28.76 28.79 28.82 28.86 28.93 28.97 29.02 29.05 29.06 29.16 29.19 29.22 29.24 29.26 29.28 29.31 29.39 29.47 29.51 29.53 29.58 29.59 29.62 29.64 29.73 29.77 29.80 29.82 29.84 29.89 29.89 28.76 JUL 29.63 29.53 29.49 29.49 29.49 29.50 29.50 29.51 29.53 29.62 29.64 29.73 29.76 29.79 29.87 29.89 29.63 29.48 29.42 29.41 29.38 29.38 29.36 29.34 29.34 29.34 29.34 29.34 29.37 29.39 29.41 29.89 29.34 AUG 29.44 29.49 29.53 29.58 29.63 29.67 29.72 29.76 29.82 29.87 29.90 29.94 29.98 30.02 30.05 30.08 30.11 30.15 30.19 30.22 30.26 30.30 29.75 29.71 29.71 29.75 29.79 29.82 29.84 29.85 29.88 30.30 29.44 SEP 29.91 29.94 29.94 29.96 29.98 30.02 30.07 30.11 30.17 30.22 30.27 30.31 30.36 30.40 30.44 30.49 30.53 30.57 30.61 30.64 30.68 30.72 30.76 30.79 30.82 30.85 30.87 30.89 30.92 30.96 30.96 29.91 CJQ o: 18 23 28 33 I \ M A M J J ASONDJFMAMJJ ASONDJFMAMJJ AS 1989 1990 1991 475 GROUND-WATER LEVELS RIO INABON TO RIO LOCO BASINS 180133066503300. Local number, 132. LOCATION.—Lat 18°01'33", long 66°50'33". Owneri Pittsburg Plata Glace 4. Name i Yauco 2. AQUIFER.--Limeston* of Tertiary Age. NELL CHARACTERISTICS.—Drilled observation well, cased 20 in (0.51 m) 0-20 ft (0-6.1 m), 12 in (0.30 m) perforated pipe 20-84 ft (6.1-25.61 m), 10 in (0.25 m) perforated pipe 84-190 ft (25.61-57.93 m). Depth 190 ft (57.93 m). DATUM.—Elevation of land-curface datum i« about 75 ft (22.87 m) above mean tea level, from topographic map. Measuring pointi Top of shelter floor, 2.35 ft (0.72 m) above land-surface datum. REMARKS.—Recording observation well. * PERIOD OF RECORD.--July 1972 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, +0.12 ft (0.04 m) below land-surface datum, July 19, 1979; lowest water level recorded, 36.91 ft (11.25 m) below land-surface datum, June 27, 1974. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 14.35 14.27 14.00 13.96 13.91 13.84 13.73 13.65 13.51 12.79 12.50 12.20 11.82 11.43 10.96 10.65 10.05 9.74 9.28 9.02 7.88 7.28 7.25 6.87 5.96 3.89 4.82 4.89 5.02 5.32 5.65 14.35 3.89 NOV 5.90 6.06 6.19 6.28 6.17 6.12 6.24 6.31 6.36 6.42 6.48 6.53 6.56 6.61 6.64 6.65 6.64 6.70 6.75 6.77 6.77 6.78 6.80 6.81 6.83 6.84 6.85 6.88 6.91 6.92 6.92 5.90 DEC 6.94 6.95 6.98 7.00 7.01 7.10 7.11 7.13 7.13 7.14 7.15 7.10 7.11 7.12 7.15 7.16 7.16 7.18 7.18 7.19 7.21 JAN 7.31 7.31 7.33 7.35 7.39 7.40 7.41 7.43 7.47 7.56 7.53 7.22 7.08 7.29 7.37 .46 .54 .60 .66 7.22 7.24 7.25 7.28 7.28 7.30 7.30 6.94 7.65 7.76 7.84 7.92 7.93 8.00 8.06 8.07 8.18 8.24 8.20 7.89 8.24 7.08 FEB 7.70 7.67 7.67 7.74 7.80 7.83 7.77 7.82 7.89 7.95 7.91 7.84 7.74 7.75 7.77 7.76 7.76 7.80 7.81 7.78 7.84 7.90 7.95 8.04 8.13 8.22 8.34 8.42 8.42 7.67 MAR 8.49 8.54 8.58 8.69 8.73 8.79 8.84 8.90 8.97 9.03 9.10 9.19 9.26 9.36 9.42 9.50 9.58 9.67 9.74 9.86 10.00 10.09 10.06 10.12 10.22 10.31 9.79 9.67 9.63 9.67 9.71 10.31 8.49 APR 9.76 9.82 9.89 9.95 10.04 9.89 9.72 9.61 9.59 9.58 9.61 9.67 9.73 9.78 9.86 9.93 10.01 10.09 10.19 10.32 10.39 10.51 10.63 10.74 10.85 10.96 11.08 11.13 11.21 11.29 11.29 9.58 MAY 11.40 11.50 11.59 11.67 11.69 11.74 11.42 11.07 10.78 10.69 10.53 10.21 10.06 9.86 9.81 9.75 9.72 9.69 9.63 9.60 9.57 9.59 9.67 9.73 9.79 9.80 9.82 9.89 10.03 10.15 10.27 11.74 9.57 JUN 10.36 10.40 10.53 10.67 10.75 10.88 11.00 11.10 11.15 11.29 11.37 11.52 11.67 11.80 11.88 11.93 12.02 12.15 12.31 12.44 12.54 12.65 12.72 12.87 13.00 13.05 13.20 13.31 13.44 13.51 13.51 10.36 JUL 13.62 13.74 13.87 13.58 13.69 13.85 13.92 13.96 14.00 14.06 14.11 14.16 14.18 14.18 14.28 14.33 14.23 14.17 13.77 13.73 13.67 13.62 13.54 13.52 13.50 13.51 13.52 13.54 13.30 13.33 13.34 14.33 13.30 AUG 13.31 13.31 13.33 13.37 13.42 12.98 13.06 13.10 13.11 13.20 13.27 13.32 13.37 13.44 13.53 13.61 13.69 13.77 13.86 13.96 14.08 14.17 14.04 13.93 13.94 13.94 13.94 13.96 14.00 14.05 14.10 14.17 12.98 SEP 14.14 14.20 14.27 14.38 14.54 14.68 14.73 14.74 14.79 14.83 14.91 15.01 15.07 15.14 15.25 14.80 14.79 14.60 14.69 14.71 14.71 14.59 14.59 14.59 14.57 14.56 14.56 14.56 14.56 14.56 15.25 14.14 WTR YR 1991 MEAN 10.28 LOW 15.25 HIGH 3.89 U " I3 14 20 J *•>. x. XJ \ "A•\J/ -«•. ••^ s\\\ V\*r\r-t1 ^ »-» A, \^r\ •\ Sr ONDJFMAMJJ ASONDJ FMAMJJ ASONDJ FMAMJJ AS 1988 1989 1990 1991 + Above land-surface datum. 476 GROUND-WATER LEVELS RIO GUANAJIBO BASIN 180132067033800. Local number, 143. LOCATION.—Lat 18«01'32", long 67«03'38". Owners Pedro P. Vivoni. Names Vivoni, Hacienda Ami•tad. AQUIFER.--Limestone of unknown age. NELL CHARACTERISTICS.--Drilled unuied irrigation well, diameter 12 in (0.30 m) . Depth 200 ft (60.98 m) . DATUM.—Elevation of land-iurface datum i« about 52.5 ft (16.0 m) above mean «ea level, from topographic m Measuring points Hole aide of caiing, 0.80 ft (0.24 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.—December 1981 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 37.36 ft (11.39 m) below land-«urface datum, 1985; loweit water level recorded, 40.0 ft (12.2 m) below land-«urface datum, June 9, 10, 11, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 39.12 39.12 39.12 39.07 39.01 39.01 38.99 38.97 38.98 38.97 38.96 38.98 38.90 38.90 38.80 38.79 38.79 38.76 39.12 38.76 NOV 37.99 38.01 38.01 38.00 38.02 38.04 38.03 38.03 38.02 38.03 38.02 37.97 37.92 37.96 37.99 37.99 37.96 37.94 37.97 38.00 38.04 38.03 38.02 38.03 38.04 38.03 38.04 37.92 DEC 38.04 38.03 38.06 38.09 38.06 38.06 38.08 38.09 38.09 38.08 38.10 38.14 38.13 38.17 38.17 38.19 38.17 38.15 38.22 38.23 38.21 38.19 38.19 38.20 38.23 38.27 38.27 38.28 38.32 38.34 38.34 38.34 38.03 JAN 38.34 38.33 38.34 38.35 38.42 38.42 38.44 38.44 38.44 38.49 38.46 38.48 38.50 38.52 38.55 38.58 38.57 38.59 38.60 38.56 38.55 38.58 38.63 38.63 38.64 38.64 38.65 38.68 38.73 38.73 38.73 38.73 38.33 FEB 38.73 38.73 38.67 38.68 38.66 38.65 38.66 38.67 38.73 38.73 38.74 38.75 38.75 38.73 38.77 38.80 38.81 38.81 38.80 38.79 38.79 38.81 38.82 38.84 38.82 38.84 38.87 38.90 38.90 38.65 MAR 38.91 38.89 38.85 38.84 38.88 38.86 38.87 38.87 38.89 38.91 38.92 38.97 38.98 38.99 39.02 39.02 39.04 39.03 39.00 39.01 39.05 39.05 39.02 39.01 39.02 APR 39.02 39.01 39.02 39.04 39.03 39.00 38.99 38.99 39.01 38.99 39.02 39.02 39.02 39.01 39.03 39.06 38.96 38.93 38.96 38.97 38.98 38.99 39.02 39.05 39.06 MAY 39.10 39.10 39.08 39.10 39.12 39.15 39.13 39.14 39.14 39.17 39.17 39.14 39.16 39.16 39.15 39.15 39.16 39.16 39.14 39.14 39.15 39.18 39.20 39.20 39.20 JUN 39.16 39.18 39.18 39.17 39.16 39.18 39.22 39.23 39.23 39.24 39.25 39.25 39.27 39.26 39.26 39.26 39.27 39.27 39.27 39.28 39.27 39.28 39.32 39.33 39.33 39.04 39.00 39.00 38.99 39.03 39.07 39.06 39.07 39.10 39.10 39.11 —— 39.19 39.21 39.18 39.15 39.14 39.16 39.31 39.35 39.34 39.32 39.32 —— 39.07 38.84 39.11 38.93 39.21 39.08 39.35 39.16 JUL 39.34 39.36 39.34 39.31 39.29 39.29 39.28 39.27 39.29 39.30 39.29 39.28 39.28 39.29 39.29 39.31 39.26 39.28 39.28 39.32 39.32 39.34 39.32 39.33 39.36 39.36 39.33 39.33 39.33 39.33 39.34 39.36 39.26 AUG 39.33 39.35 39.35 39.35 39.36 39.38 39.38 39.36 39.36 39.37 39.37 39.36 39.33 39.32 39.32 39.34 39.34 39.34 39.36 39.36 39.37 39.34 39.34 39.38 39.35 39.33 39.33 39.34 39.34 39.32 39.34 39.38 39.32 Nov. 20, SEP 39.37 39.37 39.37 39.38 39.40 39.41 39.42 39.39 39.40 39.42 39.41 39.41 39.41 39.42 39.41 39.41 39.41 39.41 39.41 39.41 39.43 39.44 39.45 39.43 39.40 39.40 39.39 39.40 39.42 39.39 39.45 39.37 2 3 J'.o Ul4 ml to £ui 38.5 S£ _jo: £w 39.5 aA tfZ ^ .n. ^ •N\s,^^ I***1 V.^ "^v V.J ff r\ •*v\ Vs, W *s,/r («WV/ ^s ^\s\- •A *-vs, "•% •ft* «^» ONDJ FMAMJ J ASONDJ FMAMJJ ASONDJ FMAMJJ AS 1988 1989 1990 1991 477 GROUND-WATER LEVELS RIO CULBBRINAS BASIN „,.»«_ ono *.. cased 6 in (0.15 m) . Depth 300 rt 182018066593200. Local number, 83. LOCATION. — Lat 18°20'18", long 66°59'32". Owner i P.R. Energy and Power Authority. Kama i San Sebastian Well. AQUIFER. — San Sebastian Formation. WELL CHARACTERISTICS.— Drilled observation well, diameter 6 in (0.15 m) DATUM.- -Elevation of land- surface datum is about 230 ft (70.1 m) above mean sea level, from topographic map. Measuring point i Shelter floor on top of 6 in (0.15 m) casing, 2.75 ft (0.84 m) above land-surface datum. Prior November 1985, top of casing, 2.40 ft (0.73 m) above land-surface datum. REMARKS. --Recording observation well. Formerly published as 182032066591800. PERIOD OF RECORD.— May 1967 to January 16, 1985. November 1985 to September 30, 1991, discontinued. EXTREMES FOR PERIOD OF RECORD. --Highest water level recorded, 21.95 ft (6.69 m) below land- surf ace datum, May 8, 1986| lowest water level recorded, 40.20 ft (12.25 m) below land-surface datum, Jan. 29, 1986. WATER LEVEL, IN FEET BELOW LAND-SORFACB DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 27.26 27.49 27.47 27.45 27.42 27.30 27.25 27.21 27.19 27.14 27.09 27.01 27.14 27.21 27.27 27.49 27.75 27.90 28.08 28.08 28.31 28.37 28.32 28.23 28.18 28.42 28.37 28.29 28.20 28.06 28.04 28.42 27.01 NOV 27.96 27.88 27.79 27.72 28.20 28.22 28.26 28.32 28.27 28.18 28.07 28.01 27.90 27.81 27.72 27.67 27.69 27.86 27.85 27.82 27.77 27.67 27.58 27.49 27.43 27.80 27.82 27.79 27.71 27.63 28.32 27.43 DEC 27.53 27.47 27.37 27.32 27.27 JAN 29.63 FEB 29.45 29.43 29.42 29.42 29.47 29.51 29.51 29.51 29.50 29.46 29.53 29.56 29.56 29.56 29.54 29.51 29.49 29.47 29.46 29.51 MAR 29.70 29.70 29.69 29.66 29.62 29.60 29.57 29.56 29.53 29.51 29.45 29.45 29.44 29.41 29.38 29.36 29.33 29.30 29.30 29.29 APR 29.18 29.17 29.28 29.62 29.85 29.91 29.93 29.89 29.38 29.40 29.21 MAY 29.08 29.09 29.11 28.86 28.74 28.65 28.64 28.66 28.68 28.56 28.53 28.55 28.57 28.56 28.49 28.12 28.11 27.70 27.54 27.51 JUN 27.82 27.91 27.97 28.06 28.13 28.18 28.28 28.31 28.35 28.38 28.43 28.49 28.54 28.59 28.62 28.66 28.60 28.62 28.57 28.48 JUL 27.49 27.21 26.91 26.89 26.91 26.99 27.09 27.11 26.78 26.59 26.62 26.72 26.86 27.00 27.12 27.23 27.04 27.04 27.09 27.00 29.61 29.59 29.55 29.52 29.51 29.48 29.73 29.73 29.71 —— 29.26 29.27 29.26 29.24 29.21 29.19 29.05 29.01 29.02 29.02 29.05 —— 27.53 27.27 29.63 29.48 29.73 29.42 29.70 29.19 29.93 29.01 27.30 27.40 27.48 27.56 27.64 27.73 29.11 27.04 28.01 28.09 27.77 27.58 27.57 28.66 27.57 27.36 27.44 27.52 37.25 26.97 27.00 27.52 26.59 AUQ 26.92 26.87 26.91 26.98 27.07 27.09 27.15 27.21 27.33 27.45 27.51 27.61 27.61 27.68 27.50 27.53 27.21 27.02 27.06 26.96 29.52 29.51 29.51 29.48 29.73 29.25 29.25 29.31 29.31 29.28 29.18 29.20 29.21 29.23 29.25 27.20 27.05 27.04 27.10 27.26 28.49 28.29 28.26 28.04 27.98 27.01 27.10 27.21 27.21 27.28 26.91 26.79 26.57 26.59 26.62 26.63 26.73 26.59 26.63 26.74 26.89 27.68 26.57 SEP 26.80 26.72 26.78 26.91 27.04 27.16 27.27 27.29 27.37 27.46 27.41 27.28 27.31 27.13 27.14 27.24 27.30 27.39 27.49 27.57 27.65 27.66 27.55 27.57 27.60 27.41 27.37 27.23 27.12 27.10 27.66 26.72 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM o* (H ro ro ro ro o (» o> * * , V\ s. ^ N \ >/ *\4f */ s^ f** •VI\\* V\VI JL \F 4 *~\ /• Xt^ S\r^ 0 N D J FMAMJ J ASONDJ FMAMJ J ASONDJ FMAMJ J AS 1988 1989 1990 1991 478 GROUND-WATER LEVELS RIO CULBBRINAS BASIN 182442067091700. Local number, 200 . LOCATION. —Lat 18°24'42 x•^ VNj( si S*J IP\ ONDJFMAMJJ ASONDJFMAMJJ ASONDJ F M A M J J 1988 1989 1990 1991 AS 479 Water Records U.S. Virgin Islands 480 ST. THOMAS, U.S. VIRGIN ISLANDS 50252000 BONNE RESOUJTION OUT AT BONNE RESOLUTION, ST. THOMAS, VI LOCATION.--Lat 18«21'57", long 64°57'34 1> , Hydrologic Unit 21020001, on right bank near Hull Bay Road, 0.5 mi (0.8 km) upstream from Atlantic Ocean, and 2.5 mi (4.0 km) northwest of Fort Christian, Charlotte Amalie. DRAINAGE AREA.—0.49 mi* (1.27 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—December 1962 to February 1967, March 1979 to April 1981, May 1982 to current year. GAQB.—Water-stage recorder and crest-stage gage. Elevation of gage is 280 ft (85 m), from topographic map. December 1962 to February 1967 and March 1979 to April 1981 at site about 100 ft (30 m) upstream at different datum. REMARKS.--Records poor. AVERAGE DISCHARGE.—13 years (1964-66, 1980, 1983-91), 0.33 ftVs (0.009 mVs), 9.14 in/yr (232 mm/yr), 239 acre-ft/yr (0.295 hmVyr); median of yearly mean discharges, 0.32 ftVs (0.01 mVs), 232 acre-ft/yr (0.29 hmVyr). EXTREMES FOR PERIOD OF RECORD.—Maximum discharge, 1,650 ft3/* (46.7 mVs), Apr. 18, 1983, gage height, 7.00 ft (2.134 m), from floodmarks, from rating curve extended above 1.0 ftVs (0.03 •?/•) on basis of critical-depth analysis and slope-area measurement of peak flow; no flow at times in most years. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 50 ftVs (1.42 mVs) and maximum (*)t Date Oct. 16 Oct. 19 Til 1400 0230 Discharge (ftVs) (mVs) Gage height (ft) (m) 255 •738 7.22 20.90 3.76 *5.71 1.146 1.740 Date Oct. 26 Discharge Time (ftVs) (ms /s) 0100 300 8.50 Minimum daily discharge, 0.01 ftVs (0.0003 mVs), many days. Gage height (ft) (m) 3.98 1.213 DAY OCT DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX KIN AC-FT CFSM IN. CAL YR WTR YR .01 .01 .02 .01 .02 .02 .11 .03 .03 .08 .06 .08 .38 .33 .08 11 .49 .18 21 2.5 2.8 .69 .57 .47 .61 16 .49 .29 .22 .17 .14 58.89 1.90 21 .01 117 3.88 4.47 1990 TOTAL 1991 TOTAL .12 .11 .11 .11 .09 .08 .07 .06 .05 .05 .05 .04 .04 .04 .05 .04 .04 .04 .03 .24 .07 .06 .05 .11 .08 .05 .05 .04 .07 .04 —— 2.08 .069 .24 .03 4.1 .14 .16 77.30 71.52 .03 .05 .04 .03 .03 .03 .03 .03 .03 .03 .03 .03 .03 .03 .03 .03 .03 .03 .03 .03 .04 .03 .04 .03 .03 .03 .03 .08 .14 .07 .69 1.84 .059 .69 .03 3.6 .12 .14 MEAN .21 MEAN .20 .18 .09 .10 .08 .07 .07 .05 .05 .06 .05 .05 .06 .04 .04 .04 .05 .06 .05 .04 .04 .07 .05 .04 .05 .04 .04 .04 .03 .03 .03 .04 1.73 .056 .18 .03 3.4 .11 .13 MAX 21 MAX 21 .04 .04 .04 .03 .03 .08 .07 .04 .03 .03 .03 .22 .06 .04 .05 .05 .05 .08 .15 .11 .07 .07 .07 .06 .05 .05 .05 .05 —— —— 1.74 .062 .22 .03 3.5 .13 .13 MIN .01 MIN .01 .05 .06 .06 .05 .05 .05 .04 .04 .04 .04 .04 .04 .04 .04 .04 .02 .02 .04 .02 .02 .02 .07 .03 .03 .03 .03 .03 .03 .03 .04 • 03, 1.17 .038 .07 .02 2.3 .08 .09 AC-FT 153 AC-FT 142 .03 .03 .03 .03 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .03 .03 .02 .02 .02 .04 .03 .02 .02 .02 .02 —— 0.69 .023 .04 .02 1.4 .05 .05 CFSM CFSM .03 .03 .03 .03 .04 .03 .03 .06 .02 .03 .03 .02 .02 .01 .01 .02 .04 .04 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .02 .03 .02 0.69 .022 .06 .01 1.4 .05 .05 .43 IN. .40 IN. .01 .01 .02 .02 .02 .02 .02 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .06 .02 .01 .01 .02 .01 .01 .01 .01 .01 .62 —— 1.03 .034 .62 .01 2.0 .07 .08 5.87 5.43 .03 .02 .02 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .02 .01 .02 .01 .01 .01 .02 .02 .02 .01 .01 .01 .01 .01 .01 .01 0.40 .013 .03 .01 .8 .03 .03 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .02 .01 .02 .01 .01 .01 .02 .02 .02 .02 .02 0.38 .012 .02 .01 .8 .03 .03 .01 .11 .01 .02 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .04 .09 .04 .04 .03 .03 .02 .15 .12 —— 0.88 .029 .15 .01 1.7 .06 .07 481 ST. THOMAS, 0.8. VIRGIN ISLANDS 50276000 TURPENTINE RUN AT MARIENDAL, ST. THOMAS, VI LOCATION.—Lat 18<>19'48", long 64°S2'S8 I> , Hydrologic Unit 21020001, on right bank, at Mariendal, 1.0 mi (1.6 km) up*trearn from Mouth, and 3.3 mi (5.3 km) southeast of Fort Christian, Charlotte Amalie. DRAINAGE AREA.--2.97 mi* (7.69 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—January 1963 to April 1969, October 1978 to September 1980, June 1982 to July 1986, July 1986 to current year (high-water discharges only). GAGE.—Crest-stage gage. Elevation of gage is 40 ft (12 m), from topographic map. REMARKS.—Records poor, peak discharges only. AVERAGE DISCHARGES.—10 years (1964-68, 1979-80, 1983-85), 1.22 ft1/* (0.034 m'/s), 5.58 in/yr (142 mm/yr), 884 acre-ft/yr (1.09 hmVyr); median of yearly mean discharges, 0.54 ftVs (0.015 mVs), 390 acre-ft/yr (0.48 hmVyr). EXTREMES FOR PERIOD OF RECORD.—Maximum discharge, 9,710 ftV» (275 mVs), Apr. 18, 1983, gage height, 11.09 ft (3.380 m), from floodmark, from rating curve extended above 500 ft*/« (14.2 mVs) on basis of slope area measurement and step-backwater analysis; no flow many days from 1963 to 1969, and in 1984. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 100 ftVs (2.83 mVs) and maximum (*) : Discharge Gage height Discharge Gage height Date Time (ftVs) (mVs) (ft) (m) Date Time (ft1/*) (•?/•) (ft) (m) Oct. 16 1430 *337 9.54 *3.88 1.183 No other peak greater than base discharge. 482 ST. JOHN, U.S. VIRGIN ISLANDS 50295000 GUINEA GOT AT BBTHANY, ST. JOHN, VI LOCATION.—Lat 18°19'55-, long 64«46'50", Rydrologic Unit 21020001, 600 ft (183 m) southeast of Bethany Church, and 1.0 ml (1.6 km) east of Government House at Cruz Bay. DRAINAGE AREA.— 0.37 mi* (0.96 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—January 1963 to October 1967, September 1982 to current year. GAGE.—Water-(tag* recorder and concrete control. Elevation of gage 1m 260 ft (79 m), fro* topographic map. Prior to September 1982, at datum 1.00 ft (0.30 m) higher. REMARKS.—Record* poor. AVERAGE DISCHARGE.—13 year* (1964-67, 1983-91), 0.091 ft1/" (0.002 m*/s), 3.340 in/yr (84.84 mm/yr) 65.93 acre-ft/yr (0.081 bmVyr); median of yearly mean di(charge*, 0.03 ft*/s (0.001 •?/•), 21.7 acre-ft/yr (0.03 bmVyr). EXTREMES FOR PERIOD OF RECORD.--maximum discharge, 946 ft1/* (26.8 mVs), Apr. 18, 1983, gage height, 5.33 ft (1.625 m), from floodmark, from rating curve extended above 1.0 fts/s (0.028 mV") on basis of step-backwater analysis and dope-area measurement of peak flow; no flow many days each year. EXTREMES FOR CURRENT YEAR.—Peak discharge* greater than base discharge of 10 ftVe (0.283 mVs) and maximum (*) t Date Time Discharge Time (ft1/") (•?/•) Date Oct. 20 1500 *7.00 No flow many days. Gage height (ft) (m) Discharge (ftV") (»?/•) 0.198 *1.94 0.591 Gage height (ft) (m) DAY OCT DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES NOV DEC JAN FEE MAR APR MAY JUN JUL AUQ SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .07 1.7 2.1 .82 .31 .01 .01 .01 .01 .01 .02 .02 .02 5.11 .16 2.1 .00 10 .45 .51 1990 1991 .02 .02 .01 .02 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .02 .01 .01 .01 .01 .01 .01 .02 .02 .02 .02 .02 .01 .02 —— 0.40 .013 .02 .01 .8 .04 .04 TOTAL 11.16 TOTAL 6.36 .01 .01 .01 .01 .01 .01 .01 .01 .02 .02 .02 .02 .02 .02 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .00 .00 .00 .01 .01 .01 .02 0.35 .011 .02 .00 .7 .03 .04 MEAN MEAN .01 .01 .02 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.21 .007 .02 .00 .4 .02 .02 .031 MAX .017 MAX .00 .00 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 —— —— — 0.01 .000 .01 .00 .02 .00 .00 2.1 MIN 2.1 MIN .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 .000 .00 .00 .00 .00 .00 . 00 AC-FT . 00 AC-FT .01 .01 .00 .00 .00 .00 .00 .03 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .01 .00 .00 .00 .00 .00 .01 0.07 .002 .03 .00 .1 .01 .01 22 CFSM 13 CFSM .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.21 .007 .01 .00 .4 .02 .02 .08 IN. .05 IN. .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 .000 .00 .00 .00 .00 .00 1.12 .64 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 .000 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 ..00 .00 0.00 .000 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 .000 .00 .00 .00 .00 .00 483 ST. CROIZ, U.S. VIRGIN ISLANDS 50333500 RIVER GOT NEAR GOLDEN GROVE, ST. CROIX, VI LOCATION.—Lat 17«42'46-, long 64«47'58-, Hydrologic Unit 21020002, on right bank, 0.4 mi (0.6 km) from Experimental Station, 0.9 mi (1.4 km) from intersection of Highway 66 and road 64, 0.3 mi (0.5 km) from University of the U.S. Virgin Islands (UVI). DRAINAGE AREA.--5.40 mi' (9.14 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—August 1990 to current year. GAGB.—Mater-stage recorder. Elevation of gage is 40 ft (12 a), from topographic amp. RBMARKS.—Records poor. Gage-height and precipitation satellite telemetry at station. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 75 ftVs (2.12 mVs) and maximum (*)« Discharge Gage height Discharge Gage height Date Time (ftVs) (m'/«) (ft) (m) Date Time (ftVs) (m3/.) (ft) (m) Oct. 10 2100 101 2.86 45.10 13.746 Oct. 16 1800 92.0 2.60 44.98 13.710 Oct. 11 1900 265 7.50 46.65 14.219 Oct. 26 0030 *860 24.40 *49.03 14.944 Oct. 14 1000 335 9.49 47.08 14.350 No flow many days. DISCHARGE, CUBIC FEET PER SECOND, MATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SBP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. .00 .00 .00 .00 .00 .00 .00 .00 12 9.6 47 33 14 54 6.6 18 9.2 3.3 1.3 4.9 11 1.4 .50 .63 11 169 8.3 2.5 1.7 1.0 1.2 421.13 13.6 169 .00 835 2.52 2.90 1.1 .95. .59 7.2 2.7 1.2 .96 .81 .62 .20 .07 .03 .00 .00 .00 .00 .00 .00 .00 7.5 1.2 .20 .03 .01 .00 .01 .07 .03 .01 .02 —— 25.51 .85 7.5 .00 51 .16 .18 .11 .11 .05 .01 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.29 .009 .11 .00 .6 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 .000 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 — 0.00 .000 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 .000 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 —— 0.00 .000 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 .000 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 —— 0.00 .000 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 .000 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 .000 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 .000 .00 .00 .00 .00 .00 WTR YR 1991 TOTAL 446.93 MEAN 1.22 MAX 169 MIN .00 AC-FT 886 CFSM .23 IN. 3.08 484 ST. CROIZ, U.S. VIRGIN ISLANDS 50345000 JOLLY HILL GOT AT JOLLY HILL, ST. CROIX, VI LOCATION.—Lat 17°44'00", long 64«51'47", Hydrologic Unit 21020002, on Mahogany Road at Jolly Hill, 1.8 mi (2.9 km) northeast of Frederiksted. DRAINAGE AREA.--2.10 mi" (5.44 km"). HATER-DISCHARGE RECORDS PERIOD OF RECORD.—January 1963 to December 1968. monthly measurements, 1962-69. October 1982 to current year. GAQB.—Water-stage recorder, crest-stage gage and sharp-crested concrete control. Elevation of gage is 140 ft (43 m), from topographic map. REMARKS.—Records poor. Low-water diversions upstream from station. Gage-height and precipitation satellite telemetry at station. AVERAGE DISCHARGE.--14 years (1964-66, 1983-91), 0.200 ft1/* (0.006 m/'s), 1.31 in/yr (33.27 mm/yr), 146 acre-ft/yr (0.180 hmVyr); median of yearly mean discharges, 0.14 ft'/s (0.004 m*/s), 101 acre-ft/yr (0.12 hmVyr). EXTREMES FOR PERIOD OF RECORD. - -Maximum discharge, 430 ft'/s (12.18 mVs), Nov.27, 1987, gage height, 4.14 ft (1.262 m) i no flow many days each year. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 25 ft'/s (0.71 m*/s) and maximum (*)t Discharge Gage height Discharge Gage height Date Time (ft'/s) (mVs) (ft) (m) Date Time (ftVs) (m>/s) (ft) (m) Oct. IS 1515 *208 5.89 *3.24 0.988 No other peak greater than base discharge. No flow many days. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES • DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 IS 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC-FT CFSM IN. CAL YR WTR YR .07 .OS .09 .09 .10 .13 .11 .13 .15 .14 .IS .IS .19 .28 .22 18 2.7 2.0 2.0 3.0 4.0 3.0 2.7 2.S 2.4 5.9 3.S 3.4 3.2 3.0 2.9 SS.48 2.14 18 .OS 132 1.02 1.18 1990 1991 2.7 2.7 2.5 2.7 2.4 2.0 1.9 1.8 l.S 1.5 1.5 1.5 1.5 1.7 1.4 1.3 1.3 1.2 1.2 1.2 1.2 1.1 1.0 .92 .93 .88 .85 .80 .77 .81 —— 44.86 1.50 2.7 .77 89 .71 .79 TOTAL 18S. TOTAL 144. .81 .78 .73 .72 .69 .65 .62 .57 .SO .59 .55 .53 .54 .51 .51 .52 .48 .46 .46 .44 .44 .42 .40 .39 .39 .36 .37 .37 .36 .35 .34 15.95 .51 .81 .34 32 .25 .28 SI MEAN 97 MEAN .32 .33 .33 .33 .33 .29 .29 .28 .26 .26 .26 .26 .23 .22 .24 .25 .28 .28 .27 .26 .27 .24 .24 .22 .22 .22 .24 .25 .20 .19 .21 8.07 .26 .33 .19 IS .12 .14 .51 MAX 18 .40 MAX 18 .20 .20 .20 .20 .20 .20 .18 .18 .17 .IS .IS .15 .17 .20 .14 .14 .14 .14 .13 .13 .13 .13 .13 .13 .13 .12 .11 .12 —— 4.39 .IS .20 .11 8.7 .07 .08 MIN .00 MIN .00 .11 .12 .11 .11 .12 .12 .11 .09 .09 .08 .12 .09 .08 .08 .08 .07 .08 .08 .09 .07 .07 .08 .08 .07 .06 .OS .07 .07 .08 .08 .08 2.70 .087 .12 .OS 5.4 .04 .05 AC-FT AC-FT .09 .09 .09 .09 .09 .09 .09 .10 .11 .11 .11 .08 .04 .04 .04 .05 .05 .04 .03 .02 .03 .03 .03 .03 .02 .02 .02 .02 .02 .01 —— 1.S8 .056 .11 .01 3.3 .03 .03 370 CFSM 288 CFSM .01 .01 .01 .02 .01 .01 .02 .04 .03 .02 .01 .01 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .01 .01 .01 .02 0.55 .018 .04 .01 1.1 .01 .01 .24 IN. .19 IN. .02 .01 .01 .02 .03 .03 .01 .01 .01 .01 .01 .01 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .03 — 0.22 .007 .03 .00 .4 .00 .00 3.31 2.57 .01 .01 .01 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .01 .02 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.07 .002 .02 .00 .1 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 .000 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 — 0.00 .000 .00 .00 .00 .00 .00 485 Ground-Water Records U.S. Virgin Islands 486 GRODND-WATBR LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174225064471900. Local number, 1. LOCATION.—Lat 17°42'25", long 64«47'19". Owneri Virgin Ieland* Government. Namei Fairplains 6 (FP6). AQOIFBR.--Alluvium and marl. NELL CHARACTBRISTICS.--Drilled public supply water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). DATUM.--Elevation of land-surf ace datum im about 20 ft (6.10 m) above mean sea level, from topographic map. Measuring pointi Top of pump concrete base, 2.20 ft (0.67 m) above land-surface datum. REMARKS.--Observation well. Water level* affected by pumping. PERIOD OF RECORD.--March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level measured, 15.64 ft (4.77 m) below land-surface datum. Mar. 25, 1982; lowest water level measured, a59.26 ft (18.1 m) below land-surface datum, Apr. 25, 1990. HATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 4 a57.78 Jan. 3 a57.07 Mar. 25 19.98 Aug. 29 21.15 Oct. 29 23.02 Jan. 5 a58.39 July 25 20.95 Sept. 25 19.80 Nov. 20 17.20 a Pumping. 487 GROUND-HATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174225064472000. Local number, 2. LOCATION. —Lat 17°42'25", long 64°47'20". Owneri U.S. Oovernnent/ Virgin Islands Government. Namei USGS-10, Fairplains 2 (FP2). AQUIFER.—Alluvium and marl. NELL CHARACTERISTICS.—Drilled unused water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). DATUM.—Elevation of land-surface datum is about 20 ft (6.10 m) above mean sea level, from topographic map. measuring points Top of 0.5 in (0.01 m) hole at concrete base wall, 3.00 ft (0.91 m) above land-surface datum. RBMARKS.—Recording observation well. Nearby pumping well. PERIOD OF RECORD.—June 1983 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 19.45 ft (5.93 m) below land-surface datum, Nov. 4, 1989| lowest water level recorded, 26.46 ft (8.06 m) below land-surface datum, Aug. 25, 1990. HATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 25.33 25.87 25.90 25.92 26.01 26.04 25.99 25.95 25.90 26.05 26.03 25.86 25.85 25.70 25.55 25.36 25.26 24.91 25.05 25.04 25.04 24.91 24.81 24.74 24.74 24.40 24.39 24.32 24.21 24.18 24.09 26.05 24.09 NOV 24.08 23.80 23.54 23.50 23.57 23.60 23.62 23.52 23.53 23.47 23.39 23.32 23.30 23.30 22.82 22.70 22.80 23.18 23.15 22.38 22.90 22.95 22.87 22.93 23.00 23.06 23.01 22.97 23.05 23.01 24.08 22.38 DEC JAN 22.99 22.97 22.54 22.80 22.85 22.86 22.82 22.76 22.83 22.77 22.80 22.90 22.88 22.87 22.91 22.83 22.79 22.87 22.92 22.94 22.97 22.88 22.82 22.78 22.90 22.89 22.84 22.84 22.78 22.74 22.72 22.99 22.54 22.70 22.68 22.77 22.82 22.82 22.66 22.65 22.67 22.76 22.85 22.86 22.82 22.79 22.19 22.30 22.15 22.36 22.35 22.37 22.30 22.26 22.33 22.56 22.60 22.57 22.62 22.62 22.58 22.65 22.68 22.84 22.86 22.15 FBB 22.81 21.99 22.37 22.36 22.45 22.57 22.57 22.64 22.64 22.67 22.66 22.68 22.67 22.75 22.76 22.89 22.83 22.81 22.85 22.98 22.71 22.69 22.73 22.72 22.63 22.72 22.70 22.69 22.98 21.99 MAR 22.83 22.82 22.77 22.69 22.84 22.77 22.72 22.80 22.77 22.71 22.72 22.72 22.79 22.94 22.84 22.87 22.88 22.85 22.81 22.87 22.95 22.96 22.91 22.90 22.86 22.83 22.94 22.92 22.88 22.97 23.02 23.02 22.69 APR 22.96 22.96 23.10 23.04 23.07 23.03 23.04 22.98 22.98 22.98 23.13 23.19 23.14 23.10 23.08 23.19 23.20 23.17 23.15 23.18 23.15 23.13 23.18 23.19 23.21 23.32 23.34 23.38 23.39 23.49 23.49 22.96 MAY 23.55 23.61 23.44 23.56 23.56 23.57 23.59 23.61 23.53 23.70 23.68 23.66 23.67 23.78 23.73 23.70 23.65 23.64 23.56 23.54 23.64 23.71 23.69 23.68 23.65 23.62 23.59 23.57 23.68 23.68 23.72 23.78 23.44 JUN 23.68 23.69 23.63 23.51 23.60 23.60 23.68 23.67 23.67 23.58 23.60 23.58 23.65 23.79 23.64 23.63 23.52 23.51 23.56 23.60 23.67 23.77 23.77 23.49 23.50 23.47 23.39 23.45 23.68 23.58 23.79 23.39 JUL 23.69 23.86 23.77 23.80 23.83 23.64 23.73 23.76 23.93 24.02 24.01 24.02 24.09 23.62 24.00 24.04 24.12 24.19 24.20 24.20 24.22 24.21 24.23 24.32 24.31 24.25 24.35 24.30 24.30 24.39 24.44 24.44 23.62 AUG 24.37 24.31 24.26 24.40 24.31 24.32 24.33 24.36 24.33 24.33 24.25 24.26 24.33 24.38 24.30 24.34 24.33 24.32 24.30 24.47 24.47 24.45 24.48 24.48 24.60 24.60 24.45 24.32 24.57 24.58 24.59 24.60 24.25 SEP 24.54 24.45 24.43 24.48 24.48 24.57 24.54 24.51 24.46 24.58 24.57 24.58 24.58 24.44 24.51 24.35 24.45 24.43 24.37 24.37 24.33 24.30 24.27 24.36 24.18 24.25 24.23 24.20 24.14 24.10 24.58 24.10 WTR YR 1991 MEAN 23.56 LOW 26.05 HIGH 21.99 19 22 25 9ft pMM -O V^ ^ *V s* sw <\/\ *Ji 11 /V^K v N\A i*j Mi > •xwx JV ^v •Vw *> ** H> *V *> A 1990 1991 488 GROUND-WATER LEVELS ST. CROIX, O.S. VIRGIN ISLANDS 174243064475100. Local number, 3. LOCATION.--Lat 17°42'43", long 64°47'51". Owner: O.S. Government, Virgin Islands Government. Name: Golden Grove - 6 (PW6). AQUIFER.--Alluvium and marl. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 8 in (0.20 m), cased 8 in (0.20 m) . DATUM.--Elevation of land-surface datum is about 40 ft (12.2 m) above mean sea level, from topographic map. Measuring point: Upper edge of hole at 8 in (0.20 m) casing, 4.20 ft (1.28 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.—March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 12.99 ft (3.96 m) below land-surface datum, Nov. 10, 1990; lowest water level recorded, 32.80 ft (10.0 m) below land-surface datum, Aug. 28, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH —— __- —— ___ ___ --- __ __- —— _ _ __- 16.81 16.57 14.61 14.30 14.02 13.77 13.86 13.87 16.81 13.77 13.82 13.52 13.20 13.31 13.04 13.09 13.09 13.09 13.05 13.05 13.07 13.12 13.41 13.91 14.29 14.61 14.88 14.89 15.40 15.57 14.14 13.51 13.30 13.50 13.92 14.27 14.34 14.09 14.20 14.45 —— 15.57 13.04 14.47 14.04 13.41 13.69 13.91 14.21 14.52 14.80 15.00 15.20 15.45 15.81 15.92 15.73 15.81 15.94 16.18 16.69 16.95 17.17 17.35 17.53 17.73 17.68 17.67 17.77 17.89 18.52 18.74 18.94 19.11 19.11 13.41 19.27 19.48 19.60 19.80 19.99 20.32 20.31 20.33 20.38 20.45 20.52 20.56 20.28 20.72 20.86 20.81 21.12 20.88 20.80 20.65 20.85 21.12 21.36 21.02 21.03 21.47 21.57 21.73 21.85 21.97 22.06 22.06 19.27 22.19 21.53 22.36 22.42 22.39 22.52 22.70 22.76 22.80 22.90 22.92 22.96 23.00 23.08 23.45 23.83 23.95 24.05 24.16 24.22 24.28 24.38 24.46 24.55 24.61 24.70 24.78 24.70 —— 24.78 21.53 24.62 24.52 24.39 24.37 24.41 24.40 24.45 24.45 24.47 24.55 24.62 24.65 24.68 24.68 24.70 24.70 24.70 24.75 24.72 24.75 24.80 24.40 24.71 24.79 24.84 24.86 24.92 24.98 25.07 25.10 25.03 25.10 24.37 24.62 25.03 25.06 25.08 25.11 25.11 25.15 25.18 24.65 24.65 24.95 25.07 25.13 25.16 25.18 25.20 25.17 25.21 25.26 25.26 25.29 25.37 25.39 25.42 25.53 25.54 25.56 25.74 25.71 25.64 —— 25.74 24.62 25.65 25.68 25.57 25.67 25.74 25.74 25.74 25.79 25.64 25.83 25.83 25.83 25.84 25.80 25.86 25.89 25.90 25.97 26.00 26.02 26.04 26.10 26.14 26.14 26.16 26.18 26.19 26.16 26.16 26.21 26.26 26.26 25.57 26.28 26.30 26.32 26.30 26.36 26.36 26.42 26.45 26.47 26.49 26.53 26.56 26.58 26.59 26.63 26.65 26.69 26.73 26.76 26.79 26.79 26.66 26.86 26.87 26.89 26.92 26.95 26.98 27.00 26.97 27.00 26.28 27.06 27.09 27.06 27.11 27.13 27.03 27.15 27.21 27.26 27.27 27.30 27.32 27.36 27.20 27.36 27.42 27.43 27.44 27.48 27.54 27.56 27.59 27.60 27.63 27.66 27.68 27.69 27.72 27.78 27.69 27.66 27.78 27.03 27.65 27.65 27.66 27.68 27.70 27.87 27.92 27.96 28.02 28.05 28.11 28.14 28.18 28.21 28.24 28.20 28.28 28.32 28.36 28.42 28.44 28.46 28.52 28.57 28.60 28.63 28.66 28.71 28.72 28.74 28.78 28.78 27.65 28.80 28.83 28.85 28.86 28.83 28.89 28.93 28.96 29.00 29.04 29.06 29.08 29.01 29.10 29.14 29.17 29.23 29.26 29.28 29.30 29.33 29.34 29.36 29.37 29.41 29.41 29.44 29.47 29.48 29.50 --- 29.50 28.80 1: I" 12 23 34 0 19 — .» N 88 — — D J 19 F 89 M A M J J •.-> A S ^ 0 N N \ D N J 19 V F 9G •— . M SJ A •~-» M -*. J ^-s J •^si A —i s f 0 \ N \ D S J 19 ^ F 91 •^*, M *-N A «»». M J "v J ^ A -*. S 489 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174245064475800. Local number, 4. LOCATION.—Lat 17°42'45", long 64°47'58". Owneri Virgin Islands Government. Namei Golden Grove - 1 (PW1). AQUIFER.—Alluvium and marl. NELL CHARACTBRISTICS.—Drilled production water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m), 0-104 ft (0-31.70 m), perforated 64-104 ft (19.51-31.70 m) . Depth 104 ft (31.70 m) . DATUM.—Elevation of land-surface datum is about 40 ft (12.2 m) above mean sea level, from topographic map. Measuring point: Lower edge of 1 in. (0.02 m) pipe at pump base, 3.40 ft (1.04 m) above land-surface datum. REMARKS.--Observation well. Water levels affected by pumping. PERIOD OF RECORD.—January 1983 to current year. EXTREMES FOR PERIOD OF RECGRDt Highest water level measured, 19.08 ft (5.81 m) below land-surface datum, Nov. 26, 1990; lowest water level measured, a58.30 ft (17.77 m) below land-surface datum, September 27, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 24 32.96 Jan. 3 20.35 Mar. 25 a47.62 Aug. 1 a48.00 Nov. 1 20.51 Feb. 5 a47.39 May 1 a47.82 Aug. 29 a47.76 Nov. 26 19.08 Mar. 4 a47.90 June 17 a50.22 Sept. 25 30.78 a Pumping. 490 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174303064484400. Local number, 6. LOCATION.—Lat 17°43'03", long 64°48'44 I> . Owneri U.S. Government, Virgin Islands Government. Namei Adventure 28. AQUIFER.—Alluvium of Pleistocene age and marl of Oligocene age. WELL CHARACTERISTICS.—Drilled unused water-table well, diameter 4 in (0.10 m), cased 4 in (0.10 m). Depth 97 ft (29.6 m). DATUM.--Elevation of land-surface datum is about 80 ft (24.39 m) above mean sea level, from topographic map. Measuring pointt Upper edge of hole at 4 in (0.10 m) casing, 2.00 ft (0.61 m) above land-surface datum. Prior June 20, 1983, top of 4 in (0.10 m) casing, 0.90 ft (0.27 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.—August 1973 to March 1974, discontinued. March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level measured, 22.80 ft (6.95 m) below land-surface datum, Feb. 13, 1991; lowest water level recorded, 40.18 ft (12.25 m) below land-surface datum, Aug. 5, 1984. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 24 25.71 Jan. 16 23.35 Mar. 27 23.82 July 1 27.15 Nov. 15 23.80 Feb. 13 22.80 Apr. 24 24.60 Aug. 16 31.42 Dec. 13 23.48 Mar. 1 22.86 May 30 25.67 Sept. 10 32.73 491 GROUND-WATER LEVELS ST. CROIZ, U.S. VIRGIN ISLANDS 174525064460600. Local number, 7. LOCATION.--Lat 17°45'25", long £4°46'0£ > . Owneri Virgin Islands Government. Namei Concordia 14. AQUIFER.--Sand and gravel. WELL CHARACTERISTICS.—Drilled production water-table well, diameter 6 in (0.15 m), earned 6 in (0.15 m) . Depth 85 ft (25.91 m). DATUM.—Elevation of land-surface datum is about 40 ft (12.2 m) above mean sea level, from topographic map. Measuring pointi Top of 0.50 in (0.01 m) pipe on top of pump concrete bale, 2.30 ft (0.70 m) above land-surface datum. REMARKS.—Observation well. Water levels affected by pumpage. PERIOD OF RECORD.—March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level measured, 10.07 ft (3.07 m) below land-surface datum, Mar. 4, 1989; lowest water level measured, a48.20 ft (a!4.7 m) below land-surface datum, Aug. 24, 1990. MATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 5 a43.63 Jan. 3 a34.47 Mar. 4 a39.£9 May 2 a45.30 Oct. 30 13.41 Jan. 5 a25.98 Mar. 26 a43.43 174527064460100. Local number, 8. LOCATION.—Lat 17«45'27', long 64°4£'01*. Owneri Virgin Islands Government. Name i Concordia 1 (Main pump house). AQUIFER.—Limestone of Tertiary Age. WELL CHARACTERISTICS.—Drilled production water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Depth 82 ft (25.0 m). DATUM.—Elevation of land-surface datum is about 40 ft (12.2 m) above mean sea level, from topographic map. Measuring pointi Top of fi in (0.15 m) casing, 2.20 ft (0.67 m) above land-surface datum. REMARKS.—Observation well. Water levels affected by pumpage. PERIOD OF RECORD.—March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 14.03 ft (4.28 m) below land-surface datum, Jan. 19, 1988» lowest water level measured, a48.29 ft (a!4.7 m) below land-surface datum, Aug. 29, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 5 a48.21 Feb. 5 a24.12 Mar. 26 a35.98 June 24 a46.50 Oct. 30 a20.85 Mar. 4 a29.45 May 2 a44.46 Aug. 28 a4£.77 Jan. 3 a24.22 a Pumping. 492 GROUND-WATER LEVELS ST. CROIX, D.S. VIRGIN ISLANDS 174532064460300. Local number, 9. LOCATION.—Lat 17°45'32", long 64°46'03". Owneri Virgin Island* Government. Namei Concordia 7. AQUIFER.—Limestone of Tertiary Age. WELL CHARACTERISTICS.—Drilled production water-table well, diameter 6 in (0.15 m), cased 0-81 ft (0-24.7 m). Depth 81 ft (24.7 m). DATUM.—Elevation of land-surface datum is 35 ft (10.7 m) above mean sea level, from topographic map. Measuring pointi Hole in pump base, 2.20 ft (0.67 m) above land-surface datum. Previous to Mar. 25, 1982, hole in pump base 2.50 ft (0.76 m) above land-surface datum. REMARKS.--Observation well. Water levels affected by pumping. PERIOD OF RECORD.—June 1962 to October 1968, discontinued. March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 1.75 ft (0.53 m) below land-surface datum, May 11, 1966; lowest water level measured, 57.40 ft (17.5 m) below land-surface datum, Mar. 5, 1964. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 5 a36.29 Jan. 3 a20.90 Mar. 4 a20.18 Aug. 28 a45.95 Oct. 30 a!2.90 Feb. 5 a20.00 June 24 a48.20 174329064454700. Local number, 10. LOCATION.—Lat 17°43'29", long 64°45'47". Owneri Virgin Islands Government. Name i Barren Spot 5 (PWD-5). AQUIFER.—Alluvium and marl. HELL CHARACTERISTICS.—Drilled production water-table well, diameter 6 in (0.15 m), cased 0-130 ft (0-39.63 m), perforated 71-130 ft (21.64-39.63 m). Depth 130 ft (39.63 m) . DATUM.—Elevation of land-surface datum is about 75 ft (22.86 m) above mean sea level, from topographic map. Measuring pointi Hole on top of pump base, 2.00 ft (0.61 m) above land-surface datum. REMARKS.--Observation well. Water levels affected by pumping. PERIOD OF RECORD.—March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level measured, 61.86 ft (18.86 m) below land-surface datum. Mar. 26, 1982; lowest water level measured, a79.81 ft (a24.33 m) below land-surface datum, June 25, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 4 a79.00 Dec. 27 a77.25 Mar. 25 a76.67 July 24 a77.94 Oct. 30 a76.80 Jan. 6 a77.13 May 2 a77.02 Aug. 27 a78.23 Nov. 19 a77.02 Mar. 5 67.98 June 20 a77.74 Sept. 23 a76.72 a Pumping. 493 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174303064481100. Local number, 11. LOCATION.—Lat 17°43'03-, long 64°18'11". Owners U.S. Virgin Islands Water and Power Authority Namei WAPA-02 at Adventure wall field. AQUIFER.—Alluvium and Kingshill Limestone. WELL CHARACTBRISTICS.—Drilled observation well, diameter 4 in (0.10 m), cased 0-60 ft (0-18.3 m), screened 20-40 ft (6.09-12.2 m) . Depth 100 ft (30.5 m). DATUM.--Elevation of land-surface datum is about 50 ft (15.2 m) above mean sea level, from topographic map. Measuring points Top of shelter floor, 2.00 ft (0.61 m) above land-surface datum. REMARKS.—Recording obeservation wall. PERIOD OF RECORD.--February 27, 1990 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 9.75 ft (2.97 m) below land-surface datum, Oct. 26, 27, 1990; lowest water level recorded, 21.31 ft (6.49 m) below land-surface datum, Apr. 3, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 15.34 15.34 15.36 15.32 15.29 15.31 15.30 15.29 15.30 14.50 13.90 13.09 12.80 12.48 11.91 11.91 11.53 11.53 11.53 11.53 11.31 11.24 11.24 11.23 11.23 9.79 10.07 —— ___ —— 15.36 9.79 ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ 10.07 10.66 10.62 10.58 10.61 10.62 10.57 9.92 9.95 10.01 10.09 10.09 10.09 10.06 10.20 10.06 10.03 10.66 9.92 10.03' 9.92 9.96 9.99 9.95 9.94 9.96 9.96 9.95 9.92 9.93 9.94 9.95 9.98 9.96 9.94 9.92 11.81 10.03 9.99 9.97 9.96 9.96 9.98 9.99 9.99 9.99 10.00 9.99 9.96 9.95 11.81 9.92 9.91 9.90 9.91 9.93 9.96 9.94 9.92 9.93 9.95 9.93 9.90 9.89 9.90 10.08 9.94 10.10 9.96 9.98 9.93 9.91 9.93 9.94 9.97 9.97 9.96 9.99 10.01 10.03 10.04 10.06 10.10 10.10 9.89 10.03 9.98 9.97 9.99 10.01 10.04 9.94 9.92 9.92 9.92 .94 .93 .90 .83 .84 .84 .83 .81 .81 9.83 9.84 9.85 9.90 9.93 9.92 9.97 10.04 10.11 ___ --- 10.11 9.81 10.15 10.17 10.16 10.21 10.23 10.21 10.32 10.30 10.32 10.33 10.37 14.24 10.78 10.47 10.45 10.47 10.49 10.53 10.52 10.57 10.58 10.60 10.60 10.65 10.69 10.76 10.79 10.81 10.85 10.88 10.90 14.24 10.15 10.91 10.92 10.97 11.02 11.04 11.04 11.08 11.13 11.11 11.11 11.13 11.13 11.16 11.17 11.20 11.23 11.66 11.24 11.32 11.35 11.38 11.38 11.43 11.51 11.53 11.55 11.57 11.62 11.75 12.38 --- 12.38 10.91 12.42 12.41 12.37 12.03 11.93 11.88 11.84 11.81 11.78 11.80 11.77 11.77 11.77 11.80 11.84 11.80 11.95 11.94 11.98 11.98 11.98 12.01 12.03 12.19 12.15 12.23 12.32 12.39 12.45 12.44 12.41 12.45 11.77 12.38 12.38 12.38 12.38 12.39 12.44 12.47 12.48 12.49 12.52 15.52 15.29 15.12 15.02 14.42 14.92 14.83 14.76 14.72 14.68 14.64 14.63 14.61 14.79 14.72 14.41 13.11 13.07 13.06 13.07 —— 15.52 12.38 13.07 13.07 13.08 13.26 13.40 13.54 13.63 13.67 13.71 13.74 13.76 13.92 13.96 13.93 13.92 13.90 13.88 13.85 13.88 13.90 13.90 13.92 13.95 14.45 14.20 14.24 14.23 14.15 14.21 14.22 14.17 14.45 13.07 14.16 14.29 14.32 14.25 14.25 14.29 14.30 14.30 14.33 14.36 14.38 14.40 14.43 14.61 14.60 14.55 14.64 17.22 16.01 14.82 14.65 14.54 14.54 14.52 14.41 14.38 14.43 14.80 14.58 14.85 14.98 17.22 14.16 15.06 15.10 15.15 15.52 15.29 15.15 15.10 15.14 15.06 15.40 15.11 15.11 15.11 15.06 15.06 15.03 15.06 15.08 15.11 15.23 15.30 15.27 15.28 15.36 15.44 15.68 15.99 16.11 16.14 15.90 16.14 15.03 ig "1 to FM 1990 MJJ ASONDJ F 1991 MAMJJ AS 494 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174308064482800. Local number, 12. LOCATION.—Lat 17 0 43'08", long 64°48'28'. Owneri U.S. Virgin Islands Water and Power Authority. Namei WAPA-03 at Adventure well field. AQUIFER.--Kingshill Limestone. WELL CHARACTERISTICS.—Drilled observation well, diameter 4 in (0.10 m), cased 0-110 ft (0-33.5 m), screened 50-90 ft (15.2-27.4 a). Depth 110 ft (33.5 m). DATUM.—Elevation of land-surf ace datum is about 60 ft (18.3 m) above mean sea level, from topographic map. Measuring points Top of shelter floor, 3.00 ft (0.91 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.—February 28, 1990 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 16.13 ft (4.92 m) below land-surface datum, Feb. 25, 1991; lowest water level recorded, 30.46 ft (9.28 m) below land-surface datum, Apr. 5, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 23.00 22.97 22.90 22.80 22.76 22.73 22.73 22.69 22.57 22.51 22.42 22.37 22.23 22.20 21.87 21.76 21.54 21.19 21.05 20.81 20.60 20.42 20.27 20.15 20.01 19.86 19.76 18.74 18.61 18.57 18.47 23.00 18.47 18.39 18.37 18.34 18.20 18.20 18.12 17.97 17.88 17.85 17.82 17.77 17.76 17.76 17.78 17.81 17.78 17.75 17.81 17.86 17.85 17.73 17.65 17.59 17.55 17.51 17.43 17.39 17.35 17.34 17.23 —— 18.39 17.23 17.23 17.22 17.22 17.22 17.22 17.20 17.20 17.20 17.19 17.16 17.18 17.17 17.16 17.18 17.20 17.17 17.16 17.18 17.19 17.19 17.18 17.16 17.16 17.16 17.17 17.18 17.18 17.17 17.15 17.09 16.99 17.23 16.99 16.95 16.96 16.93 16.85 16.82 16.84 16.82 16.80 16.83 16.81 16.86 16.83 16.78 16.79 16.77 16.76 16.78 16.77 16.75 16.71 16.73 16.75 16.82 16.79 16.75 16.76 16.74 16.77 16.80 16.74 16.70 16.96 16.70 16.64 16.55 16.52 16.48 16.52 16.48 16.47 16.51 16.47 16.40 16.40 16.37 16.20 16.15 16.15 16.14 16.17 16.14 16.14 16.16 16.19 16.25 16.18 16.15 16.15 16.19 16.20 16.21 —— 16.64 16.14 16.23 16.29 16.24 16.27 16.28 16.28 16.67 16.42 17.36 16.55 16.43 21.42 17.34 16.83 16.66 16.62 16.55 16.67 16.57 16.59 16.59 16.65 16.62 16.59 16.68 16.65 16.64 16.73 16.68 16.73 16.71 21.42 16.23 16.73 16.69 16.69 16.75 16.80 16.80 16.77 16.76 16.78 16.82 16.82 16.82 16.85 16.80 16.87 16.89 17.71 16.99 16.93 16.93 16.96 16.95 16.98 17.08 18.14 22.67 23.16 23.39 23.55 23.88 —— 23.88 16.69 24.06 24.17 24.30 24.26 24.25 24.27 24.24 24.29 24.31 24.34 24.36 24.40 24.43 24.48 24.22 24.13 24.24 22.70 23.84 24.39 24.59 24.71 24.78 22.69 22.69 22.69 22.68 22.68 23.78 24.33 24.62 24.78 22.68 24.76 24.88 24.98 24.88 25.04 25.15 25.18 25.22 25.26 25.31 25.34 25.40 25.45 25.46 25.48 25.34 25.52 24.75 24.30 24.07 23.91 23.90 23.71 22.60 22.60 22.60 22.59 24.68 25.37 24.92 —— 25.52 22.59 25.67 25.80 25.65 25.80 25.87 24.18 25.81 25.94 26.05 26.09 26.10 26.18 26.24 26.24 26.25 26.33 26.31 26.29 26.29 26.31 26.31 26.41 26.38 26.40 26.53 26.61 26.63 26.64 26.65 26.65 26.68 26.68 24.18 26.73 26.79 26.80 26.84 26.85 26.86 26.88 26.92 26.98 26.99 27.02 27.06 27.08 27.12 27.11 27.22 27.33 27.34 27.45 27.54 27.58 27.61 27.68 27.78 27.78 27.80 27.93 27.69 27.80 27.92 27.91 27.93 26.73 27.95 27.92 27.92 27.93 28.07 28.21 28.21 28.21 28.19 28.27 28.37 28.41 28.41 28.19 28.36 28.38 28.49 28.48 28.46 28.64 28.70 28.62 28.54 28.57 28.79 28.75 28.71 28.66 24.88 27.73 —— 28.79 24.88 WTR YR 1991 MEAN 21.24 LOW 28.79 HIGH 16.14 ~j£ 24 cf=> IJQ < 32 F 19 .A M 90 ( A M J J A S y 0 /-^ N • !!• • ••id D f<» *•*•• J 19£ F n r M nr A M J C, J •"v. A ^v. S 495 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174316064480800. Local number, 13. LOCATION.—Lat 17«43'16", long 64 048'08". Owneri U.S. Virgins Islands Water and Power Authority. Namei WAPA-17 at Adventure well field. AQUIFER.—Kingshill Limestone. WELL CHARACTBRISTICS.—Drilled observation well, diameter 4 in (0.10 m), cased 0-95 ft (0-29.0 m), screened 10-40 ft (3.05-12.2 m) . Depth 95 ft (29.0 m). DATUM.--Elevation of land-surface datum is about 75 ft (22.9 m) above mean sea level, from topographic map. Measuring pointi Top of shelter floor, 2.33 ft (0.71 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—February 28, 1990 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 4.68 ft (1.43 m) below land-surface datum, Oct. 14 1990; lowest water level recorded, 14.49 ft (4.42 m) below land-surface datum, Sept. 28-29, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUQ SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 11.60 11.62 11.62 11.62 11.62 11.62 11.63 11. S3 11.55 9.78 8.22 5.90 5.86 —— ___ —— —— —— 11.63 5.86 5.70 5.77 5.83 5.69 5.51 S.C7 5.71 5.77 5.81 5.86 5.90 5.95 5.98 6.00 5.97 5.96 5.95 5.92 5.92 6.15 6.51 6.34 6.20 .13 .09 .08 .10 .08 .05 .07 6.51 5.51 6.10 6.10 6.06 6.02 6.01 5.98 5.94 5.92 5.91 5.90 5.88 5.87 5.88 5.87 5.87 5.89 5.89 5.88 5.85 5.85 5.85 5.86 5.86 5.85 5.86 5.87 5.87 5.86 5.88 5.88 5.91 6.10 5.85 5.92 5.93 5.93 5.91 5.92 5.93 5.94 5.93 5.95 5.95 5.96 5.95 5.95 5.97 5.96 5.98 5.98 5.98 5.98 5.98 5.99 5.99 6.01 6.01 6.02 6.02 6.03 6.04 6.05 6.05 6.06 6.06 5.91 6.05 6.04 6.04 6.06 6.06 6.02 6.02 6.04 6.04 6.06 6.07 6.07 5.93 5.96 5.99 6.01 6.01 6.01 6.02 6.03 6.03 6.05 6.06 6.07 6.07 6.08 6.09 6.12 —— 6.12 5.93 6.13 6.13 6.13 6.16 6.15 6.15 6.18 6.19 6.21 6.23 6.27 6.34 6.36 6.38 6.42 6.44 6.47 6.50 6.47 6.50 6.54 6.57 6.59 6.64 6.67 6.70 6.71 6.76 6.81 6.85 6.88 6.88 6.13 6.91 6.94 6.98 7.03 7.07 7.11 7.16 7.12 7.14 7.20 7.25 7.28 7.32 7.34 7.40 7.44 7.45 7.48 7.53 7.58 7.63 7.66 7.72 7.76 7.83 7.88 7.92 7.96 8.01 8.17 —— 8.17 6.91 8.29 8.41 8.51 8.61 8.69 8.78 8.85 8.91 8.96 9.05 9.11 9.16 9.21 9.28 9.33 9.40 9.47 9.45 9.47 9.51 9.58 9.66 9.71 9.78 9.77 9.73 9.70 9.69 9.78 9.88 9.95 9.95 8.29 10.02 10.09 10.16 10.22 10.27 10.33 10.40 10.46 10.52 10.58 10.64 10.67 10.70 10.76 10.80 10.84 10.90 10.96 11.05 11.07 11.09 11.13 11.16 11.15 11.17 11.25 11.30 11.35 11.39 11.44 —— 11.44 10.02 11.47 11.51 11.55 11.58 11.62 11.66 11.69 11.73 11.78 11.81 11.85 11.89 11.93 11.97 12.01 11.98 12.03 12.06 12.09 12.12 12.14 12.17 12.19 12.21 12.25 12.27 12.30 12.33 12.35 12.38 12.40 12.40 11.47 12.43 12.46 12.48 12.51 12.53 12.57 12.59 12.64 12.67 12.69 12.72 12.75 12.78 12.80 12.83 12.86 12.87 12.90 12.95 12.99 13.02 13.05 13.07 13.10 13.13 13.16 13.19 13.22 13.24 13.27 13.32 13.32 12.43 13.37 13.44 13.48 13.52 13.57 13.61 13.67 13.72 13.77 13.79 13.82 13.86 13.90 13.96 14.00 14.04 14.08 14.13 14.17 14.22 14.25 14.28 14.31 14.34 14.37 14.42 14.45 14.48 14.45 14.36 —— 14.48 13.37 3* « !TiO Hui -}£ 10 cfc E* ifi • -^ — -^-*, •^^ — >-^ -JW/ ^v •^-N "N ^ X ^, "^ ^ FMAMJJ ASONDJ FMAHJJ 1990 1991 AS 496 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174247064475701. Local number, 14. LOCATION.—Lat 17°42'47-, long 64°47'57 B . Owner! U.S. Virgins Islands Water and Power Authority. Namet WAPA-21a at Golden Grove well field. AQUIFER.—Alluvial, Kingshill Limestone. WELL CHARACTERISTICS.—Drilled observation well, diameter 4 in (0.10 m), cased 0-70 ft (0-21.3 m), screened 15-70 ft (4.57-21.3 m). Depth 100 ft (30.5 m), well collapsed to 70 ft (21.3 m). DATUM.—Elevation of land-surface datum is about 52 ft (15.8 m) above mean sea level, from topographic map. Measuring points Top of shelter floor, 3.25 ft (0.99 m) above land-surface datum. REMARKS.--Recording observation well. Water levels affected by nearby pumping well. PERIOD OF RECORD.—February 28, 1990 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 14.19 ft (4.32 m) below land-surface datum, Nov. 3, 1990; lowest water level recorded, 41.61 ft (12.7 m) below land-surface datum, Aug. 21, 1990. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 18.74 18.52 15.79 18.74 15.79 NOV 15.18 14.19 18.15 17.74 17.45 17.17 17.94 16.82 16.77 18.04 18.36 18.72 18.35 18.23 17.82 17.19 17.72 18.38 17.97 18.72 14.19 DEC 17.84 18.51 20.70 17.93 18.48 17.74 17.82 17.92 18.68 19.51 19.84 20.22 20.51 20.71 21.00 20.12 19.97 20.10 20.28 22.48 22.74 23.12 23.47 23.47 17.74 JAN 23.73 24.21 24.33 24.78 25.13 25.28 25.90 25.78 25.86 26.06 25.96 26.02 23.09 26.41 26.74 25.81 27.30 25.88 27.35 27.89 24.69 25.98 27.68 27.73 27.93 28.03 28.26 28.32 28.32 23.09 FEB 28.38 23.62 29.03 28.69 28.57 39.02 29.46 29.22 29.25 29.40 29.22 29.15 29.21 29.25 MAR 29.46 23.62 30.53 30.73 30.83 30.87 31.04 31.22 30.90 30.95 31.07 31.22 30.53 APR 26.89 30.57 30.69 30.85 30.99 31.24 31.33 31.12 29.97 31.48 31.63 32.57 35.25 32.49 31.67 35.25 26.89 MAY 32.01 31.98 29.12 32.12 32.39 31.79 31.88 32.50 28.76 32.68 32.36 32.22 32.11 30.11 32.11 32.41 32.35 32.91 32.54 32.45 32.30 32.40 32.65 32.49 32.52 32.56 32.46 32.21 32.14 32.47 32.69 32.91 28.76 JUN 32.73 32.87 32.81 30.75 32.48 32.60 33.22 33.41 33.17 33.27 33.18 33.24 33.44 33.37 31.20 33.60 33.44 33.73 33.66 33.73 33.63 33.23 34.84 34.12 33.91 33.27 33.85 34.12 33.90 32.92 34.84 30.75 JUL 34.27 34.21 33.80 34.25 34.12 32.49 34.27 34.25 34.13 34.39 34.64 34.64 34.85 29.62 34.68 34.35 34.68 34.36 35.35 35.37 35.67 35.14 35.35 35.22 35.38 35.47 35.27 35.29 35.89 32.06 31.83 35.89 29.62 AUG 31.90 31.84 31.98 32.29 32.34 36.30 36.29 36.43 36.63 36.65 36.76 36.90 36.99 37.13 33.58 35.35 36.97 37.19 37.40 37.38 37.59 37.60 37.71 37.72 37.76 37.74 37.54 37.53 37.75 37.80 37.72 37.80 31.84 SEP 37.88 37.77 37.87 37.47 37.46 37.75 37.36 37.50 37.95 37.75 37.53 37.74 37.72 37.72 37.72 37.63 37.67 37.67 37.60 37.65 37.65 37.74 37.80 37.76 37.40 37.40 37.40 37.50 37.52 37.55 37.95 37.36 1* 15 "1 So .^LJ 25 35 F M 1990 A M 0 N D J F 1991 MAM 497 GROUND-WATER LEVELS ST. CROIZ, U.S. VIRGIN ISLANDS 174319064454401. Local number, 15. LOCATION.--Lat 17°43'19", long 64°45'44 >> . Owneri U.S. Virgin* Ieland* Water and Power Authority. Namei WAPA-23a at Barren Spot well field. AQUIFER.--Post King•hill Limestone. WELL CHARACTERISTICS.--Drilled observation well, diameter 4 in (0.10 m), cased 0-110 ft (0-33.5 m), screened 70-110 ft (21.3-33.5 m). Depth 110 ft (33.5 m). DATUM.--Elevation of land-surface datum is about 65 ft (19.8 m) above mean sea level, from topographic map. Measuring pointi Top of shelter floor, 3.50 ft (1.07 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—February 28, 1990 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level recorded, 56.84 ft (17.3 m) below land-surface datum, Feb. 13, 1991; lowest water level recorded, 69.68 ft (21.3 m) below land-surface datum, Sept. 29, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HI OH 60.95 61.37 61.40 61.34 61.31 61.29 61.27 60.66 60.33 60.98 60.98 61.11 61.12 60.77 60.97 59.29 60.74 60.74 60.67 60.53 60.53 60.51 60.51 58.40 57.60 57.80 57.51 57.49 56.94 57.26 57.41 61.40 56.94 59.24 59.39 59.47 59.47 59.56 59.60 59.64 59.60 59.61 58.40 59.50 59.58 59.65 59.79 59.81 59.80 58.31 58.16 58.07 58.61 59.58 59.55 59.50 59.47 59.46 59.46 59.46 59.49 59.78 59.97 59.97 58.07 60.02 60.04 58.24 60.00 60.09 60.13 60.15 60.16 60.01 60.16 60.20 60.23 60.23 60.23 60.25 60.25 60.26 60.26 60.27 60.28 60.28 60.29 60.27 60.29 60.29 60.34 60.32 60.34 58.16 59.32 59.38 60.34 58.16 59.38 59.35 59.52 60.10 58.46 59.54 59.97 60.16 60.24 60.29 60.31 60.35 60.40 60.45 60.48 59.54 60.46 60.47 60.44 60.47 60.44 60.44 60.43 60.29 60.19 60.16 60.16 60.17 60.46 60.53 60.54 60.54 58.46 60.58 60.58 60.52 60.57 60.58 59.37 60.25 60.29 58.20 57.44 57.17 56.98 56.85 59.53 59.68 59.98 60.08 60.15 60.27 60.33 60.39 60.47 59.50 60.53 60.08 59.92 59.73 59.66 ___ —— 60.58 56.85 59.62 59.83 59.92 59.94 59.51 60.10 60.06 60.36 60.50 60.47 60.43 60.42 60.52 60.57 60.59 60.61 60.62 60.70 60.59 60.47 60.44 60.45 60.41 60.30 60.27 — - _ 59.78 59.98 60.02 60.03 60.03 60.70 59.51 59.90 59.78 60.10 60.52 60.63 60.65 60.68 60.70 60.71 60.73 60.55 60.56 60.71 60.72 60.72 60.72 60.71 60.78 60.80 60.82 60.83 60.35 60.24 60.18 59.96 59.91 59.91 59.90 59.89 58.41 - — 60.83 58.41 60.43 59.35 59.21 59.21 59.19 59.17 59.11 60.68 60.45 60.50 60.50 60.50 60.50 60.48 60.47 60.45 60.30 60.25 60.19 60.08 60.15 60.19 60.58 60.66 60.72 60.76 60.77 60.77 60.77 60.85 60.86 60.86 59.11 60.87 58.86 60.74 59.98 60.77 60.89 60.94 60.91 60.84 60.79 60.80 —— —— 61.08 61.13 61.17 61.11 61.17 61.13 61.22 61.22 61.23 60.95 —— 61.23 58.86 61.20 61.22 61.09 61.18 61.21 60.53 61.10 61.17 61.22 61.25 61.28 61.29 61.30 60.00 60.87 60.95 61.00 61.15 61.20 61.27 59.49 61.20 61.29 61.31 61.33 61.40 61.40 61.43 59.77 59.28 60.98 61.43 59.28 61.16 61.26 61.30 61.35 61.36 61.38 61.40 61.43 61.44 61.45 61.45 61.44 61.43 61.43 61.34 61.46 61.46 58.78 60.12 60.97 61.16 61.27 61.34 61.44 61.44 61.44 61.44 61.46 61.49 61.49 61.49 61.49 58.78 61.50 61.37 61.24 61.18 61.22 61.28 61.63 61.93 62.24 62.58 62.89 63.20 63.51 62.41 62.92 62.97 63.28 63.21 63.47 63.79 64.13 64.47 64.83 66.34 65.99 67.67 68.07 68.46 65.86 64.23 68.46 61.18 -£ 62 -^\t«d okj\;AUla.A,^uy U L ajyL \\ £ FMAMJJASONDJFMAMJJAS 1990 1991 498 GROUND-WATER LEVELS ST. THOMAS, U.S. VIRGIN ISLANDS 182050064580400. Local number, 1. LOCATION.—Lat 18«20'50", long 64°58'04". Owneri U.S. Government, Virgin Islands GoverniMint. Namei Thach Farm-Dudovick. AQUIFER.—Volcanic rocks of Cretaceous age. WELL CHARACTERISTICS.—Drilled water-table production well, diameter 6 in (0.15 m), cased 6 in (0.15 m) 0-25 ft (0-7.62 m), open hole 25-80 ft (7.62-24.4 m). Depth 80 ft (24.4 m). DATUM.—Elevation of land-surface datum is 80 ft (24.4 m) above mean sea level, from topographic map. Measuring pointi Top of 6 in (0.15 m) casing, 2.50 ft (0.76 m) above land-surface datum. Prior to Mar. 23, 1982, top of 6 in (0.15 m) casing, 1.30 ft (0.40 m) above land-surface datum. REMARKS.--Non-potable public-water supply and observation well. Since 1982, this well had been reported as USGS-8. However, this well is not USOS-8 which is located 250 feet south of this well. PERIOD OF RECORD.—October 1963 to August 1969, discontinued. March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 2.33 ft (0.71 m) below land-surface datum, Nov. 20, 1984; lowest water level measured, a60.26 ft (18.37 m) below land-surface datum. Mar. 8, 1989. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 30 a20.82 Dec. 26 a22.74 Mar. 4 a35.30 Aug. 15 a59.90 Nov. 29 a!6.90 Jan. 28 30.19 Mar. 27 a39.75 Sept. 16 58.37 182138064543100. Local number, 2. LOCATION.—Lat 18<>21'38", long 64°54'31-. Owneri Mahogany Run Resort. Namei Mahogany 15. AQUIFER.--Fractured rocks. WELL CHARACTERISTICS.—Drilled public supply water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Depth 145 ft (44.21 m). DATUM.—Elevation of land-surface datum is 100 ft (30.5 m) above mean sea level, from topographic map. Prior to this report, elevation used was 120 ft (36.6 m). measuring pointi Top of 6 in (0.15 m) casing, 0.10 ft (0.03 m) below land-surface datum. Prior September 16, 1991, 0.00 ft (0.00 m), prior May 31, 1991, 1.30 ft (0.40 m), and prior March 4, 1991, 1.20 ft (0.36 m) below land-surface datum. REMARKS.—Observation well. Water levels affected by nearby pumping well. Well is now active and pumping. PERIOD OF RECORD.—March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 12.45 ft (3.79 m) below land-surface datum, July 1, 1986} lowest water level measured, a!20.92 ft (36.9 m) below land-surface datum, Aug. 15, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 24 33.36 Dec. 26 29.59 Mar. 4 30.49 May 31 a56.38 Nov. 28 27.52 Jan. 28 30.50 Mar. 27 31.12 Aug. 15 a!20.92 182138064542500. Local number, 3. LOCATION.—Lat 18°21'38", long 64°54'25". Owneri Mahogany Run Resort. Namei Mahogany 16. AQUIFER.--Fractured rocks. WELL CHARACTERISTICS.—Drilled water-table production well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Depth 145 ft (44.21 m). DATUM.—Elevation of land-surf ace datum is 100 (30.5 m) above mean sea level, from topographic map. Prior to this report, elevation used was 130 ft (39.6 m). Measuring point» Top of 6 in (0.15 m) casing, 1.30 ft (0.40 m) below land-surface datum. REMARKS.--Water levels affected by nearby pumping well. PERIOD OF RECORD.—March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level measured, 10.25 (3.12 m) below land-surface datum Jan. 21, 1988} lowest water level measured, a!03.85 ft (31.65 m) below land-surface datum, Oct. 4, 1984. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 24 37.90 Jan. 28 36.30 May 31 49.70 Aug. 15 57.97 Nov. 28 33.40 Mar. 4 36.48 July 12 56.93 Sept. 16 57.65 Dec. 26 35.51 Mar. 27 37.08 a Pumping. 499 GROUND-WATER LEVELS ST. THOMAS, U.S. VIRGIN ISLANDS 182136064541900. Local number, 4. LOCATION.—Lat 18°21'36", long 64°54'19". Owneri Mahogany Run Resort Namei Mahogany 17. AQUIFER.—Fractured rock. WELL CHARACTERISTICS.—Drilled water-table production well, diameter 6 in (0.15 m), cased 6 in (0.15 m) . Depth 145 ft (44.21 m). DATUM.—Elevation of land-surface datum is 110 ft (33.5 m) above mean sea level, from topographic map. Prior to this report, elevation used was 140 ft (42.7 m). Measuring pointt Top of 6 in (0.15 m) casing at land-surface datum. REMARKS.--Public water supply. Water levels affected by nearby pumping well. PERIOD OF RECORD.—March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 17.49 ft (5.33 m) below land-surface datum, Dec. 11 1985; lowest water level measured, a60.40 ft (18.41 m) below land-surface datum, Sept. 10, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 24 35.87 Jan. 28 38.46 May 31 44.60 Aug. 15 45.70 Nov. 28 35.15 Mar. 4 39.00 July 17 44.97 Sept. 16 45.33 Dec. 26 37.60 Mar. 27 39.52 182029064535200. Local number, 5. LOCATION.—Lat 18<>20'29-, long 64°53'52-. Owneri Virgin Islands Government, V.I. Housing Authority. Namei Donoe 3. AQUIFER.—Volcanic rock undifferentiated. Fracture at 165 ft (50.3 m), from drilling log. WELL CHARACTERISTICS.—Drilled unused water-table well, diameter 6 in (0.15 m), cased 0-20 ft (0-6.10 m), open hole 20-400 ft (6.10-122 m). Depth 400 ft (122 m). DATUM.—Elevation of land-surface datum is about 235 ft (71.6 m) above mean sea level, from topographic map. Measuring pointi Top of 6 in (0.15 m) casing, 2.30 ft (0.70 m) above land-surface datum. REMARKS.--Observation well. Well is blocked at approximately 70.0 ft (21.3 m) below land-surface datum. PERIOD OF RECORD.—March 1982 to Septmenber 30, 1991, discontinued. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 29.15 ft (8.88 m) below land-surface datum, Sept. 28, 1989; lowest water level measured, 90.98ft (27.73m) below land-surface datum, Apr. 30, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Date level Oct. 24 62.08 a Pumping. 500 GROUND-WATER LEVELS ST. THOMAS, U.S. VIRGIN ISLANDS 182038064550300. Local number, 6. LOCATION.—Lat 18°20'38", long 64°55'03". Owner: U.S. Government, Virgin Islands Government. Namei Grade School 3. AQUIFER.—Volcanic breccia. WELL CHARACTERISTICS.—Drilled unused water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Depth 70 It (21.3 m) . 1 DATUM.--Elevation of land-surface datum is about 60 ft (18.3 m) above mean sea level, from topographic map. Measuring point: Top of 0.5 in (0.01 m) hole at 6 in (0.15 m) casing, 1.30 ft (0.40 m) above land-surface datum. Prior to June 27, 1983, top of 6 in (0.15 m) casing, 2.90 ft (0.88 m) above land-surface datum. REMARKS.—Recording observation well. PERIOD OF RECORD.—March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 1.53 ft (0.47 m) below land-surface datum, Oct. 1, 1989; lowest water level recorded, 35.38 ft (10.79 m) below land-surface datum, July 21, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 28.34 28.43 28.50 28.56 28.59 28.64 28.68 28.65 28.48 28.29 28.10 27.96 27.84 27.55 27.12 26.83 26.21 25.69 25.31 24.44 23.64 22.88 22.62 22.60 22.73 22.68 21.77 21.35 21.26 21.37 21.55 28.68 21.26 NOV 21.79 22.04 22.34 22.64 22.93 23.22 23.47 23.72 23.96 24.22 24.43 24.63 24.85 25.06 25.27 25.46 25.66 25.87 26.07 26.24 26.37 26.47 26.56 26.66 26.64 26.56 26.44 26.38 26.38 26.44 26.66 21.79 DEC 26.50 26.54 26.59 26.57 26.48 26.49 26.56 26.64 26.71 26.79 26.88 26.95 27.01 27.08 27.16 27.25 27.34 27.45 27.57 27.69 27.81 27.94 28.05 28.17 28.27 28.37 28.37 26.48 JAN 28.83 28.93 29.02 29.02 28.83 FBB 29.11 29.19 29.25 29.29 29.27 29.25 29.21 29.06 28.96 28.95 29.00 29.05 29.10 29.07 28.96 28.84 28.69 28.62 28.61 28.64 28.71 28.79 28.87 29.29 28.61 MAR 28.94 29.02 29.06 28.99 28.94 28.90 28.85 28.83 28.86 28.92 29.00 29.09 29.18 29.27 29.36 APR 29.78 29.76 29.75 29.78 29.83 29.89 29.96 30.03 30.10 30.18 30.23 30.30 30.35 30.41 30.47 MAY 31.12 31.16 31.19 31.22 31.25 31.27 31.30 31.33 31.36 31.36 31.27 31.02 30.70 30.38 30.11 JUN 30.87 30.94 31.02 31.09 31.17 31.24 31.32 31.38 31.41 31.46 31.50 31.54 31.57 31.60 31.64 JUL 32.02 31.98 31.92 31.88 31.87 31.88 31.90 31.92 31.94 31.98 32.01 32.00 32.00 32.00 32.03 AUG 32.19 32.20 32.22 32.25 32.28 32.32 32.36 32.40 32.44 32.46 32.49 32.53 32.56 32.59 32.64 29.76 29.80 29.81 29.71 29.66 29.63 29.63 29.66 29.70 29.75 29.78 29.81 28.83 30.75 30.79 30.83 30.88 30.92 30.96 30.99 31.02 31.05 31.09 31.09 29.75 30.05 30.08 30.12 30.18 30.25 30.34 30.43 30.53 30.61 30.69 30.78 31.36 29.95 31.79 31.82 31.84 31.87 31.88 31.91 31.93 31.95 31.98 32.00 32.00 30.87 32.04 32.00 31.99 31.98 32.00 32.03 32.07 32.10 32.14 32.17 32.18 32.18 31.87 32.81 32.84 32.87 32.89 32.91 32.93 32.93 32.90 32.78 32.60 32.40 32.93 32.19 SEP 32.27 32.16 32.08 31.99 31.88 31.79 31.71 31.67 31.63 31.57 31.49 31.40 31.34 31.29 31.25 28.91 28.91 28.97 29.03 28.99 29.43 29.51 29.58 29.64 29.71 30.53 30.58 30.64 30.68 30.72 29.98 29.95 29.97 30.03 30.05 31.67 31.71 31.73 31.75 31.78 32.04 32.05 32.06 32.08 32.08 32.68 32.71 32.73 32.75 32.78 31.28 31.07 30.92 30.88 30.90 30.96 31.00 31.02 30.89 30.73 30.58 30.47 30.41 30.36 29.96 32.27 29.96 >UI 11 22 0 19 *~J N 88 \ff 0 J 19 ^v F 89 X M •***« A -v M •*%. J r j 1/1 A \ S ^ 0 N * 0 J 19 F 90 ••-> M V A 's M "^^ J J / A ^ S 7 0 V N \ 0 J 19 *-* F 91 X. M ^ A y^ M >•-» J J A S 501 GROUND-WATER LEVELS ST. THOMAS, U.S. VIRGIN ISLANDS 182036064545200. Local number, 7. LOCATION.--Lat 18«20'36", long 64°54'52". Owneri U.S. Virgin Islands Water and Power Authority. Namei St. Thomas Hospital, VIBO-1. AQUIFER.--Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.--Drilled observation water-table well, diameter 7 in (0.18 m), cased 4 in (0.10 m), 0-145 ft (0-44.2 m), screened 100-145 ft (30.5-44.2 m). Depth 145 ft (44.2 m). DATUM.--Elevation of land-surface datum is about 85 ft (25.9 m) above mean sea level, from topographic map. Measuring pointi Top of shelter floor, 3.20 ft (0.97 m) above land-surface datum. REMARKS.--Observation well. Drilled on February 1991. Automated digital recorder installed on May 1991. Pumping test performed during May 22-24, 1991. PERIOD OF RECORD.—May 1991 to September 1991. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 71.88 ft (21.9 m) below land-surface datum, June 16, 1991; lowest water level recorded, 74.17 ft (22.6 m) below land-surface datum, Sept. 22-23, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HI OH OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP — ___ ___ ___ — _ ___ _-_ — 72.13 72.13 72.13 72.14 72.14 72.12 ___ 73.00 72.94 72.70 72.66 ___ —— 73.00 72.12 72.79 72.89 72.99 73.03 73.08 73.08 73.16 73.23 73.24 73.08 72.84 72.59 72.35 72.11 71.95 71.89 —— --_ 71.95 71.99 72.01 72.08 72.12 72.18 72.22 72.45 —— 73.24 71.89 72.55 72.43 72.31 72.20 72.09 72.07 72.00 71.97 71.97 72.04 72.11 72.12 72.12 72.13 72.20 72.29 72.31 72.45 72.56 72.56 72.56 72.58 72.61 72.64 72.67 72.78 72.82 72.84 72.86 72.88 72.95 72.95 71.97 73.10 73.22 73.24 73.26 73.28 73.32 73.33 73.38 73.43 73.47 73.48 73.49 73.52 73.62 73.70 73.72 73.72 73.80 73.85 73.87 73.86 73.79 73.69 73.66 73.66 73.66 73.72 73.70 __- 73.87 73.10 —— —— 73.77 73.79 73.79 73.80 73.87 74.04 74.05 74.08 74.10 74.12 74.14 74.14 74.15 74.15 74.15 74.15 74.02 73.86 73.74 73.66 73.62 73.62 73.51 --- 74.15 73.51 SEP 502 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182010064472600. Local number, 1. LOCATION.—Lat 18°20'10", long 64°47'26". Owner: U.S. Government, National Park Services. Name: NPS-2 (Cruz Bay). AQUIFER.--Volcanic rocks of Cretaceous Age. WELL CHARACTERISTICS.—Drilled unused water-table well, diameter 6 in (0.15 m), 4 in (0.10 m) cased, 0-20 ft (0-6.10 m), open hole 20-99 ft (6.10-30.2 m) . Depth 99 ft (30.2 m) . DATUM.—Elevation of land-surface datum is 60 ft (18.3 m) above mean sea level, from topographic map. Measuring point: Top of 4 in (0.10 m) casing, 4.10 ft (1.25 m) above old land-surface datum after 1.40 ft (0.43 m) land fill and 2.70 ft (0.82 m) casing extension occurred. Prior to June 29, 1983, top of 4 in (0.10 m) casing, 1.40 ft (0.43 m) above land-surface datum. REMARKS.—Observation well. Hater levels affected by pumping nearby well. PERIOD OF RECORD.—May 1964, discontinued. June 30, 1983 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level measured, +1.41ft (0.43 m) above land-surface datum, May 1, 1986; lowest water level measured, 42.56 ft (12.98 m) below land-surface datum, Aug. 30, 1967. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 23 + 1.05 Jan. 30 28.83 Mar. 29 31.04 July 17 33.30 Nov. 29 23.23 Mar. 8 30.34 June 6 32.66 Aug. 17 33.75 Jan. 4 27.40 182109064460300. Local number, 2. LOCATION.—Lat 18°21'09", long 64°46'03". Owner: U.S. Government, National Park Service. Namei NPS-5 (Trunk Bay). AQUIFER.--Volcanic rocks of Cretaceous Age. WELL CHARACTERISTICS.—Drilled water-table production well, diameter 6 in (0.15 m), cased 0-12 ft (0-3.66 m), open hole 12-60 ft (3.66-18.3 m). Depth 60 ft (18.3 m). DATUM.--Elevation of land-surface datum is 60 ft (18.3 m) above mean sea level, from topographic map. Measuring point: Top of 6 in (0.15 m) casing, 0.70 ft (0.21 m) above land-surface datum. Prior to Mar. 24, 1982 top of 6 in (0.15 m) casing, 1.00 ft (0.30 m) above land-surface datum. REMARKS.—Active water supply well for recreation facilities at Trunk Bay. PERIOD OF RECORD.—August 1964 to December 1969, discontinued. March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level measured, 12.83 ft (3.91 m) below land-surface datum, Jan. 24, 1985; lowest water level measured, a57.29 ft (17.47 m) below land-surface datum, Nov. 27, 1968. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 23 37.65 Jan. 30 37.18 Mar. 29 41.03 July 17 a44.95 Nov. 29 33.33 Mar. 11 37.32 June 6 37.72 Aug. 17 a42.60 Dec. 28 35.73 a Pumping. + Above land-surface datum. GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 503 182116064451000. Local number, 3. LOCATION. —Lat 18«21'16', long 64°45'10". Owners U.S. Government, National Park Service. Names NPS-6 (Cinnamon Bay). AQUIFER.—Volcanic rock* of Cretaceous Age. WBLL CHARACTERISTICS.—Drilled water-table abandoned production well, diameter 6-in (0.15 m), cased 0-51 ft (0-15.55 m), open hole 51-70 ft (15.55-21.34 m). Depth 70 ft (21.34 m) . DATUM.—Elevation of land-.urface datum i. about 60 ft (18.3 m) above mean sea level, from topographic map. Measuring pointt Hole on 6 in (0.15 m) casing, 2.00 ft (0.61 m) above land-.urface datum. Prior to June 29, 1983, top of 6 in (0.15 m) casing at land-surface datum. REMARKS.—Recording observation well. PERIOD OP RECORD.—Auguat 1964 to December 1969, discontinued. March 1982 to current y«ar. EXTREMES FOR PERIOD OF RECORD.-Highest water level recorded, 41.12 ft (12.54 m) below land-surface datum, Aug. 15, 1969; lowest water level recorded, 63.15 ft (19.25 m) below land-surface datum, July 1, 1968. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JON JUL AUG WTR YR 1991 MEAN 58.26 LOW 59.78 HIGH 56.73 SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 57.62 57.58 57.55 57.51 57.65 57.76 57.84 57.74 57.64 57.56 57.50 57.45 57.42 57.38 57.35 57.33 57.31 57.29 57.27 57.24 57.19 57.13 57.10 57.07 57.05 57.04 57.03 57.02 56.99 56.93 56.88 57.84 56.88 56.84 56.78 56.76 56.74 56.73 56.73 56.76 56.97 57.13 57.27 57.40 57.52 57.60 57.54 57.48 57.43 57.36 57.29 57.25 57.23 57.19 57.11 57.06 57.18 57.26 57.31 57.26 57.22 57.20 57.19 57.60 56.73 57.18 57.18 57.16 57.12 57.09 57.05 57.05 57.20 57.32 57.42 57.35 57.28 57.25 57.23 57.23 57.23 57.23 57.23 57.24 57.25 57.27 57.29 57.29 57.29 57.44 57.57 57.69 57.80 57.73 57.68 57.63 57.80 57.05 57.58 57.52 57.48 57.44 57.42 57.40 57.39 57.39 57.59 57.74 57.88 57.96 58.04 57.98 57.92 57.89 57.85 57.82 57.80 57.77 57.74 57.68 57.62 57.58 57.56 57.54 57.53 57.53 57.54 57.81 57.96 58.04 57.39 58.08 58.19 58.26 58.17 58.05 57.98 57.91 57.86 57.84 57.83 57.83 57.81 57.86 57.91 57.93 57.82 57.73 57.68 57.58 57.49 57.45 57.43 57.43 57.43 57.44 57.45 57.45 57.46 —— 58.26 57.43 57.64 57.78 57.90 57.97 58.05 58.03 57.98 57.94 57.91 57.89 57.88 57.82 57.74 57.64 57.55 57.49 57.48 57.48 57.48 57.45 57.61 57.76 57.88 57.97 58.07 58.17 58.24 58.29 58.33 58.39 58.46 58.46 57.45 58.37 58.32 58.30 58.29 58.39 58.51 58.55 58.57 58.61 58.66 58.72 58.78 58.83 58.74 58.66 58.57 58.51 58.62 58.71 58.65 58.59 58.56 58.53 58.49 58.56 58.66 58.76 58.84 58.89 58.79 58.89 58.29 58.83 58.90 58.94 58.99 59.04 59.09 59.06 59.10 59.00 59.01 59.08 59.09 59.08 59.04 59.02 59.00 58.87 58.78 58.69 58.64 58.59 58.68 58.76 58.80 58.74 58.66 58.62 58.59 58.57 58.54 58.51 59.10 58.51 58.49 58.46 58.41 58.36 58.34 58.34 58.36 58.36 58.36 58.52 58.62 58.59 58.67 58.80 58.91 59.01 58.95 58.89 58.85 58.80 58.78 58.75 58.72 58.70 58.87 58.85 58.81 58.72 58.66 58.61 ___ 59.01 58.34 58.54 58.50 58.62 58.77 58.77 58.73 58.71 58.70 58.87 58.98 59.08 59.15 59.21 59.29 59.35 59.41 59.47 59.46 59.51 59.57 59.63 59.56 59.49 59.43 59.40 59.36 59.31 59.26 59.22 59.17 59.12 59.63 58.50 59.08 59.19 59.32 59.42 59.51 59.57 59.64 59.70 59.74 59.76 59.78 59.70 59.60 59.52 59.44 59.38 59.33 59.29 59.27 59.25 59.23 59.16 59.22 59.29 59.37 59.45 59.51 59.52 59.51 59.49 59.48 59.78 59.08 59.48 59.36 59.27 59.32 59.40 59.41 59.41 59.41 59.42 59.30 59.22 59.25 59.32 59.39 59.44 59.42 59.38 59.32 59.28 59.36 59.42 59.47 59.43 59.31 59.16 59.02 58.94 58.87 58.82 58.75 59.48 58.75 - 54 61 Q 63 ONDJFMAM 1988 1989 J J A S 0 N DJFMAM 1990 J J A S ONDJFM 1991 AMJJAS 504 182042064454500. Local number, 5. LOCATION. —Lat 18«20'42", long 64°45'45 Owners Virgin I.land. Government. Name t DPW-6. (Su..anaberg) GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS ' water-table well, diameter 6 in (0.15 m) , ca.ed 6 in (0.15 m) . Sounded depth DATUM.--Bievatlon'of land-.urface datum i. about 640 ft (195 m) above mean tea level, from *0W**?^c Jf*l' a Measuring pointi Top of 6 in (0.15 m) ca.ing, 1.60 ft (0.49 m) above land-.urface datum. Prior to June 28, 1983, top of 6 in (0.15 m) eating, 1.30 ft (0.40 m) above land-.urface datum. REMARKS. — Recording observation well. . recorded, 1.33 ft (0.40 m) below land-. urf.ce datum, Hay 18, 1986; lowe.t water level recorded, 24.68 ft (7.52 m) below land-.urface datum, Sept. 29, 1991. WATER LEVEL, IN FEET BELOW LAND- SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 21.37 21.39 21.41 21.42 21.43 21.44 21.44 21.44 21.44 21.44 21.39 21.37 21.37 21.36 21.34 21.33 21.30 21.29 21.24 20.75 19.07 20.23 20.23 20.17 20.09 20.05 20.01 19.99 19.99 19.99 19.99 21.44 19.07 NOV 19.99 20.03 20.03 20.06 20.07 20.09 20.12 20.16 20.22 20.25 DEC 20.60 20.63 20.66 20.70 20.71 20.73 20.74 20.76 20.76 20.89 JAN 21.52 21.52 21.51 21.49 21.43 21.38 21.35 21.34 21.34 21.34 FEB 21.81 21.83 21.85 21.85 21.86 21.86 21.86 21.86 21.8« 21.89 MAR 20.64 19.99 21.52 20.60 21.81 21.34 21.91 21.68 22.39 21.70 APR MAY JUN JUL AUQ 20.30 20.33 20.38 20.42 20.48 20.52 20.54 20.56 20.61 20.64 20.64 20.64 20.64 20.64 20.64 20.63 20.61 20.60 20.60 20.60 —— 20.89 20.90 20.93 20.99 21.02 21.06 21.11 21.14 21.19 21.22 21.26 21.29 21.33 21.37 21.41 21.44 21.46 21.50 21.51 21.51 21.52 21.34 21.34 21.34 21.35 21.38 21.42 21.45 21.47 21.51 21.52 21.55 21.57 21.59 21.61 21.63 21.66 21.68 21.70 21.74 21.76 21.81 21.91 21.91 21.83 21.79 21.73 21.71 21.70 21.69 21.69 21.68 21.68 21.68 21.68 21.68 21.68 21.68 21.68 21.68 —— —— —— 21.96 21.98 22.01 22.03 22.05 22.06 22.08 22.10 22.12 22.14 22.17 22.19 22.20 22.22 22.25 22.26 22.29 22.30 22.34 22.35 22.39 22.58 22.59 22.60 22.62 22.63 22.64 22.67 22.68 22.70 22.71 22.71 22.74 22.74 22.75 22.78 22.80 22.81 22.82 22.84 22.86 —— 22.86 22.40 23.00 22.87 23.47 23.00 23.96 23.47 24.36 23.98 SEP 21.70 21.73 21.74 21.77 21.81 21.82 21.86 21.90 21.92 21.95 22.40 22.42 22.44 22.46 22.48 22.51 22.53 22.55 22.55 22.56 22.87 22.88 22.89 22.90 22.91 22.92 22.93 22.96 22.98 22.94 23.00 23.02 23.04 23.04 23.05 23.06 23.13 23.13 23.14 23.16 23.47 23.48 23.50 23.52 23.55 23.57 23.58 23.61 23.63 23.64 23.98 24.00 24.02 24.04 24.06 24.07 24.09 24.10 24.11 24.13 24.37 24.39 24.41 24.43 24.44 24.45 24.46 24.47 24.48 24.49 23.00 23.00 22.93 22.93 22.94 22.94 22.94 22.94 22.94 22.94 22.94 22.94 22.94 22.94 22.94 22.94 22.94 22.94 22.96 22.98 22.99 23.18 23.20 23.20 23.21 23.22 23.24 23.25 23.28 23.29 23.31 23.32 23.34 23.36 23.39 23.40 23.41 23.42 23.43 23.46 23.47 —— 23.66 23.69 23.70 23.71 23.72 23.74 23.76 23.76 23.76 23.78 23.80 23.81 23.82 23.84 23.87 23.89 23.90 23.91 23.92 23.95 23.96 24.15 24.16 24.18 24.19 24.20 24.21 24.23 24.23 24.23 24.24 24.25 24.26 24.28 24.29 24.31 24.32 24.33 24.34 24.34 24.35 24.36 24.50 24.51 24.52 24.53 24.54 24.56 24.56 24.57 24.60 24.61 24.61 24.63 24.64 24.64 24.64 24.64 24.65 24.66 24.44 24.64 24.66 24.37 WTR YR 1991 MEAN 22.41 LOW 24.66 HIGH 19.07 0 5 10 15 20 \ ONDJTMAMJJASONDJFMAMJJASONDJFMAMJJAS 1988 1989 1990 1991 GROUND-WATER LEVELS SO5 ST. JOHN, U.S. VIRGIN ISLANDS 182044064454600. Local number, 6. LOCATION.—Lat 18«20'44-, long 64»45'46-. Owneri Virgin Islands Government. Name i DPW-5 AQUIFER.--Louisenhoj Formation. WELL CHARACTERISTICS.—Drilled public supply water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Sounded depth 145 ft (44.2 m). DATUM.--Elevation of land-surface datum is about 640 ft (195 m) above mean sea level, from topographic map. Measuring pointi Top of 6 in (0.15 m) casing, 1.50 ft (0.46 m) above land-surface datum. Prior Oct. 23, 1990, top of 6 in (0.15 m) casing, 1.40 ft (0.43 m) above land-surface datum. REMARKS.--Observation well. Water levels affected by pumping. PERIOD OF RECORD.—September 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 18.85ft (5.74m) below land-surface datum, July 2, 1986; lowest water level measured, a!07.4 ft (32.7 m) below land-surface datum, Sept. 19, 1985. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 23 39.08 Jan. 30 42.50 Mar. 28 42.16 July 17 49.80 Dec. 28 41.98 Mar. 8 41.79 June 6 43.38 Aug. 16 a!06.72 182044064454800. Local number, 7. LOCATION.—Lat 18°20'44, long 64°45'48-. Owneri Virgin Islands Government. Namei DPW-4 AQUIFER.—Louisenhoj Formation. WELL CHARACTERISTICS.—Drilled public supply water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Sounded depth 60 ft (18.3 m). DATUM.—Elevation of land-surface datum is about 640 ft (195 m) above mean sea level, from topographic map. Measuring pointi Top of 6 in (0.15 m) casing, 0.60 ft (0.18 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.—September 1982 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level measured, 14.48 ft (4.41 m) below land-surface datum, July 2, 1986; lowest water level measured, a50.66 ft (15.44 m) below land-surface datum, Jan. 22, 1987. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 23 27.76 Jan. 30 31.29 Mar. 28 30.91 July 17 a48.53 Nov. 30 a49.26 Mar. 8 30.56 June 6 31.76 Aug. 16 a48.49 Dec. 28 30.62 182044064454900. Local number, 8. LOCATION.—Lat 18°20'44", long 64°45'49". Owneri Virgin Islands Government. Name i DPW-3. AQUIFER.—Louisenhoj Formation. WELL CHARACTERISTICS.—Drilled public supply water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Sounded depth 110 ft (33.5 m). DATUM.—Elevation of land-surface datum is about 620 ft (189 m) above mean sea level, from topographic map. Prior to this report, elevation used was 640 ft (195 m). Measuring point: Top of 6 in (0.15 m) casing, 1.80 ft (0.55 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.—September 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 12.17ft (3.71 m) below land-surface datum, July 2, 1986; lowest water level measured, 69.58 ft (21.21 m) below land-surface datum, Feb. 27, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level June 6 27.00 July 17 28.44 Aug. 16 31.56 a Pumping. 506 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182044064455000. Local number, 9. LOCATION."Lat 18°20'44", long 64°45'50". Owneri Virgin Islands Government. Namei DPW-2. AQUIFER.—Louisenhoj Formation. WELL CHARACTERISTICS.—Drilled public supply water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Sounded depth 65 ft (19.8 m). DATUM.--Elevation of land-surface datum is about 620 ft (189 m) above mean sea level, from topographic map. Prior to this report, elevation used was 640 ft (195 m) . Measuring pointi Top of 6 in (0.15 m) casing, 2.00 ft (0.61 m) above land-surface datum. REMARKS.—Observation well. PERIOD OF RECORD.—September 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 14.93 ft (4.55 m) below land-surface datum, Dec. 19, 1989; lowest water level measured, a53.39 ft (al6.3 m) below land-surface datum, July 17, 1991 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 23 33.40 Jan. 30 36.72 Mar. 28 35.12 July 17 a53.39 Nov. 30 a49.38 Mar. 8 35.05 June 6 35.93 Aug. 16 40.98 Dec. 28 35.48 182044064455200. Local number, 10. LOCATION.—Lat 18°20'44" / long 64°45'52". Owneri Virgin Islands Government. Namei DPW-1. AQUIFER.--Louisenhoj Formation. WELL CHARACTERISTICS.—Drilled public supply water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Sounded depth 60 ft (18.3 m) . DATUM.—Elevation of land-surface datum about 610 ft (186 m) above mean sea level. Prior to this report, elevation used was 640 ft (195 m). Measuring pointi Top of 6 in (0.15 m) casing, 2.00 ft (0.61 m) above land-surface datum. REMARKS.—Observation well. Water levels affected by pumping. PERIOD OF RECORD.—September 1982 to current year. EXTREMES FOR PERIOD OF RECORD.—Highest water level measured, 13.54 ft (4.13 m) below land-surface datum, Dec. 19, 1989; lowest water level measured, 38.92 ft (11.86 m) below land-surface datum, Feb. 27, 1986 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 23 31.41 Jan. 30 34.11 Mar. 28 32.43 July 17 34.84 Nov. 30 31.16 Mar. 8 32.48 June 6 32.70 Aug. 17 37.29 Dec. 28 32.97 a Pumping. 507 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 181956064464500. Local number, 11. LOCATION.--Lat 18°19'56", long 64°46'45". Owneri Virgin Islands Government. Name i Guinea Gut Well. AQUIFER.--Louisenhoj Formation (Donnelly, 1959). WELL CHARACTBRISTICS.--Drilled unused water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Depth 85 ft (25.9 m). DATUM.--Elevation of land-surface datum is about 280 ft (85.36 m) above mean sea level, from topographic map. Measuring points Bottom of 0.5 in (0.01 m) hole at 6 in (0.15 m) casing, 1.50 ft (0.46 m) above land-surface datum. Prior to June 28, 1983, top of 6 in (0.15 m) casing, 1.80 ft (0.55 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.--March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 2.71 ft (0.79 m) below land-surface datum, Jan. 3, 1990} lowest water level recorded, 25.25 ft (7.70 m) below land-surface datum, Oct. 2, 1985. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT 17.86 17.84 17.79 17.71 17.60 17.54 17.49 17.46 17.41 17.37 17.31 17.27 17.22 17.12 16.97 16.80 16.68 16.62 16.45 15.40 10.51 8.69 8.07 7.81 7.63 7.61 7.80 8.08 8.24 8.41 8.52 17.86 7.61 NOV 8.66 8.76 8.88 8.94 8.83 8.90 8.98 9.04 9.16 9.24 9.31 9.41 9.49 9.61 9.70 9.75 9.73 9.68 9.73 9.74 9.68 9.70 9.77 9.77 9.68 9.63 9.62 9.67 9.73 9.75 9.77 8.66 DEC 9.80 9.87 9.99 10.10 10.12 10.19 10.32 10.41 10.47 10.41 10.35 10.43 10.50 10.59 10.67 10.77 10.87 10.97 11.10 11.22 11.33 11.44 11.55 11.65 11.77 11.86 11.98 12.06 12.08 12.08 12.06 12.08 9.80 JAN 11.95 11.89 11.84 11.73 11.71 11.68 11.69 11.72 11.77 11.78 11.77 11.81 11.85 11.92 11.94 11.95 11.98 12.03 12.06 12.08 12.15 12.17 12.21 12.25 12.30 12.41 12.49 12.59 12.70 12.79 12.88 12.88 11.68 FEB 12.88 12.95 12.68 12.53 12.53 12.56 12.56 12.60 12.67 12.71 12.78 12.77 12.74 12.75 12.80 12.86 12.92 12.97 12.96 12.92 12.93 12.98 13.04 13.09 13.12 13.16 13.24 13.33 13.33 12.53 MAR 13.40 13.43 13.45 13.52 13.60 13.64 13.74 13.84 13.94 14.04 14.15 14.24 14.36 14.44 14.57 14.68 14.80 14.89 14.96 15.07 15.18 15.25 15.26 15.34 15.45 15.55 15.61 15.62 15.70 15.81 15.92 15.92 13.40 APR 16.01 16.08 16.17 16.27 16.37 16.45 16.55 16.64 16.66 16.69 16.73 16.78 16.84 16.91 17.00 17.08 17.16 17.23 17.32 17.40 17.49 17.58 17.69 17.79 17.88 17.98 18.07 18.15 18.23 18.31 18.31 16.01 MAY 18.37 18.40 18.44 18.49 18.54 18.59 18.63 18.68 18.75 18.82 18.88 18.91 18.89 18.89 18.89 18.92 18.93 18.97 19.01 19.05 19.07 19.10 19.12 19.17 19.22 19.25 19.31 19.37 19.44 19.50 19.57 19.57 18.37 JUN 19.64 19.71 19.77 19.84 19.90 19.95 20.00 19.99 20.04 20.08 20.13 20.18 20.23 20.29 20.33 20.39 20.44 20.48 20.53 20.58 20.61 20.66 20.69 20.72 20.75 20.79 20.83 20.87 20.91 20.94 20.94 19.64 JUL 20.96 20.98 21.00 21.04 21.08 21.12 21.16 21.20 21.25 21.29 21.33 21.37 21.41 21.44 21.48 21.51 21.52 21.53 21.55 21.57 21.60 21.63 21.67 21.69 21.71 21.75 21.78 21.80 21.82 21.85 21.88 21.88 20.96 AUG 21.90 21.93 21.96 21.99 22.03 22.06 22.10 22.15 22.19 22.22 22.25 22.29 22.32 22.36 22.39 22.42 22.44 22.47 22.49 22.52 22.55 22.57 22.60 22.64 22.68 22.71 22.74 22.76 22.77 22.77 22.78 22.78 21.90 SEP 22.78 22.79 22.79 22.81 22.82 22.84 22.85 22.87 22.89 22.90 22.90 22.91 22.91 22.94 22.96 22.99 23.02 23.05 23.08 23.11 23.13 23.16 23.21 23.23 23.24 23.26 23.27 23.28 23.30 23.30 23.30 22.78 WTR YR 1991 MEAN 16.45 LOW 23.30 HIGH 7.61 'o u 9 18 27 ~/ /- VJ *-s s\ V\ *«•».i \ *~W "*-» ~ \ \ V J \ -> **> \s "V, •«*. »-» ^*. ONDJFMAMJJ ASONDJ FMAMJJ ASONDJ FMAMJJ AS 1988 1989 1990 1991 508 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182110064430000. Local number, 12. LOCATION. —Lat 18°21'10", long 64°43'00". Owneri U.S. Virgin Islands Water and Power Authority. Name i WAPA, Coral Bay, VIEO-2. AQUIFER. --Fractured, volcanic rock, water-table aquifer. ca «ed 4 in WELL CHARACTERISTICS. --Drilled observation water-table well, diameter 7 in (0.18 a), 0-70 ft (0-21.3 a), cased 4 in (0.10 a), 0-66 ft (0-20.1 a), screened 26-66 ft (7.26-20.1 a). Depth 66 ft (20.1 a). DATUM.— Elevation of land-surface datum is about 30 ft*(9.14 a) above mean sea level, froa topographic map. Measuring pointt Top of shelter floor, 3.10 ft (0.94 a) above land- surf ace datum. REMARKS.— Observation well. Drilled on February 1991. Automated digital recorder installed on May 1991. SEP 1991; - . - • t lowest water level recorded, 24.08 ft (7.34 a) below land-surface datum, Aug. 10-15, 1991. WATER LEVEL, IN PBBT BELOW LAND- SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 * 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HI OH OCT NOV DEC JAN PBB MAR APR MAY JUN JUL AUG — _ _ 23.65 23.66 23.64 23.61 23.59 23.57 23.55 23.55 23.54 23.53 23.52 23.51 23.50 23.49 23.48 23.48 23.48 23.49 23.51 23.54 23.56 23.57 23.66 23.48 23.57 23.59 23.59 23.60 23.60 23.62 23.63 23.64 23.65 23.65 23.66 23.65 23.64 23.64 23.64 23.65 23.66 23.68 23.69 23.70 23.72 23.73 23.74 23.74 23.75 23.76 23.77 23.77 23.78 23.78 —— 23.78 23.57 23.75 23.75 23.75 23.76 23.78 23.79 23.80 23.83 23.84 23.85 23.85 23.85 23.86 23.87 23.88 23.87 23.87 23.88 23.88 23.89 23.91 23.92 23.93 23.94 23.94 23.95 23.96 23.97 23.97 23.98 23.99 23.99 23.75 23.99 23.99 24.00 24.01 24.02 24.04 24.05 24.05 24.06 24.06 24.06 24.07 24.08 24.08 24.06 24.04 24.01 24.00 24.01 24.03 24.04 24.04 24.01 24.01 24.02 24.03 24.03 23.95 23.88 23.85 23.81 24.08 23.81 23.77 23.74 23.70 23.69 23.68 23.67 23.66 23.66 23.65 23.67 23.67 23.69 23.70 23.72 23.74 23.75 23.77 23.79 23.81 23.82 23.83 23.83 23.80 23.74 23.70 23.67 23.65 23.63 23.61 23.56 — — — 23.83 23.56 SEP GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 509 181950064422300. Local number, 13. LOCATION.—Lat 18°19'50", long 64°42'23". Owneri U.S. Virgin Iiland* Water and Power Authority. Namei WAPA, Calabash Boom, VIBO-3. AQUIFER.—Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS.—Drilled observation water-table well, diameter 7 in (0.18 m), 0-110 ft (0-33.5 m), cased 4 in (0.10 m), 0-10 ft (0-33.5 m), screened 50-110 ft (15.2-33.5 m). Depth 110 ft (33.5 m). DATUM.--Elevation of land-surface datum is about 55 ft (16.8 m) above mean sea level, from topographic map. Measuring pointi Top of shelter floor, 2.80 ft (0.85 m) above land-surface datum. REMARKS.—Observation well. Drilled on February 1991. Automated digital recorder in*tailed on Hay 1991. PERIOD OF RECORD.—May 1991 to September 1991. EXTREMES FOR PERIOD OF RECORD.--Highest water level 52.21 ft (15.9 m) below land-surface datum, Sept. 30, 1991; lowest water level recorded, 52.54 ft (16.0 m) below land-surface datum, Aug. 22, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP —— —— — ___ —— —— —— 52.30 52.29 52.28 52.29 52.28 52.28 52.28 52.28 52.28 52.28 52.28 52.28 52.28 52.29 52.29 52.31 52.31 52.32 52.31 52.31 52.31 52.31 52.32 52.28 52.31 52.31 52.31 52.30 52.29 52.29 52.29 52.29 52.29 52.29 52.29 52.29 52.29 52.29 52.28 52.29 52.29 52.29 52.29 52.29 52.29 52.30 52.32 52.32 52.32 52.33 52.33 52.34 52.34 52.34 —— 52.34 52.28 52.34 52.34 52.34 52.34 52.34 52.34 52.34 52.35 52.36 52.37 52.37 52.37 52.37 52.38 52.38 52.38 52.38 52.40 52.40 52.40 52.41 52.42 52.43 52.44 52.44 52.45 52.45 52.45 52.45 52.46 52.46 52.46 52.34 52.46 52.47 52.48 52.48 52.49 52.50 52.51 52.51 52.52 52.52 52.52 52.51 52.51 52.51 52.52 52.52 52.53 52.53 52.53 52.53 52.53 52.54 52.53 52.53 52.51 52.51 52.50 52.50 52.49 52.48 52.47 52.54 52.46 52.45 52.44 52.42 52.41 52.40 52.37 52.35 52.34 52.33 52.33 52.31 52.31 52.31 52.31 52.31 52.31 52.30 52.30 52.29 52.29 52.29 52.29 52.28 52.28 52.27 52.26 52.25 52.24 52.23 52.22 —— 52.45 52.22 "LJ 51 52 53 MAY JUN JUL 1991 AUG SEP 510 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182048064430400. Local number, 14. LOCATION. --Lat 18°20'48", long 64 043'04". Owner i U.S. Virgin Island* Water and Power Authority. Name i WAPA, Coral Bay, VIEO-4 . AQUIFER. --Fractured, volcanic rock, water-table aquifer. WELL CHARACTERISTICS. —Drilled observation water-table well, diameter 7 in (0.18 m) , 0-50 ft (0-15.2 m) , cased 6 in (0.15 m), 0-50 ft (0-15.2 m) , screened 20-50 ft (6.09-15.2 m) . Depth 50 ft (15.2 m) . DATUM. --Elevation of land-surface datum is about 13 ft (3.96 m) above mean sea level, from topographic map. Measuring point i Top of shelter floor, 3.10 ft (0.94 m) above land- surf ace datum. REMARKS. --Observation well. Drilled on February 1991. Automated digital recorder installed on May 1991. PERIOD OF RECORD. --May 1991 to September 1991. EXTREMES FOR PERIOD OF RECORD. --Highest water level recorded, 10.5 ft (3.20 m) below land-surface datum, Sept. 1991i lowest water level recorded, 11.48 ft (3.50 m) below land-surface datum, Aug. 7, 1991. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 INSTANTANEOUS OBSERVATION AT 1200 29 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP — 11.21 11.22 11.10 11.09 11.05 11.03 11.03 11.02 11.00 10.99 11.01 10.97 10.99 11.03 11.05 11.07 11.05 11.09 11.09 11.10 11.05 11.03 11.22 10.97 11.02 11.00 10.99 11.00 11.04 11.05 11.09 11.12 11.13 11.13 11.11 11.04 11.03 11.00 11.00 11.00 11.03 11.09 11.11 11.17 11.18 11.19 11.19 11.21 11.22 11.20 11.17 11.19 11.17 11.09 —— 11.22 10.99 11.07 11.08 11.11 11.14 11.17 11.22 11.27 11.31 11.30 11.29 11.24 11.20 11.19 11.17 11.16 11.14 11.21 11.24 11.28 11.33 11.35 11.36 11.36 11.31 11.32 11.32 11.29 11.29 11.30 11.28 11.29 11.36 11.07 11.31 11.36 11.41 11.42 11.43 11.46 11.46 11.41 11.35 11.30 11.27 11.26 11.30 11.29 11.23 11.28 11.29 11.31 11.36 11.36 11.34 11.28 11.24 11.23 11.21 11.20 11.10 10.96 10.95 10.95 10.95 11.46 10.95 10.95 10.94 10.95 10.95 10.93 10.87 10.83 10.78 10.76 10.79 10.81 10.82 10.85 10.88 10.91 10.91 10.93 10.94 10.94 10.92 10.90 10.83 10.70 10.67 10.62 10.62 10.59 10.59 10.54 10.58 10.95 10.54 33 9 m H fc2 HUJ 10 11 12 MAY JUN JUL 1991 AUG SEP INDEX Page 51 1 Page Access to WATSTORE data ...................... 26-27 Acre-foot, definition of ............................. 27 Adenosine triphosphate, definition of ................... 27 Adjuntas, Lago Garzas No. 1 near dam near ............................. 419-422 Adjuntas, Rio Grande de Aiecibo near ............... 60-61 Adjuntas, Rio Guilarte near ........................ 411 Agua at Playa de Ponce, Quebrada del................. 407 Aguada, Rio Culebra near .......................... 413 Aguada, Rio Culebrinas near..................... 399-400 Aguada, Rio Ingenio near .......................... 413 Aguas Buenas, Rio Caguitas near ................. 220-221 Aguas Buenas, Rio de Bayamon near .............. 150-151 Algae growth potential, definition of ................... 27 Analyses of samples collected at water-quality partial-record stations in Puerto Rico .................... 415-425 Anasco Arriba, Rio Grande de Anasco at ............... 413 Anasco, Rio Dagiiey near .......................... 413 Anasco, Rio Grande de Anasco near ............... 392-393 Aquifer, definition of .............................. 27 Arecibo, Rfo Grande de Arecibo above .............. 70-71 Arenas at Las Marias, Rio ......................... 412 Artesian, definition of ............................. 27 Artificial substrate, definition of ...................... 34 Ash mass, definition of ............................ 28 Ausubo near Ponce, Quebrada ....................... 405 B Bacteria, definition of ............................. 28 Bahia de San Juan No. 5 at San Juan .................. 182 Bairoa at Bairoa near Caguas, Rio ................. 226-227 near Caguas .............................. 228-229 Balboa, Rio Yaguez at ............................ 410 Bafios de Coamo, Rfo Coamo at ..................... 404 Bauta near Orocovis, Rfo ........................ 93-94 Bayagan near Ponce, Rio .......................... 406 Bayamon at Flood Channel at Bayamon, Rio de ............................... 156-157 near Aguas Buenas ......................... 150-151 near Bayamon ............................. 152-153 Bayamon basin, Rio de, gaging station records in ............................. 148-153 water-quality records in ...................... 150-157 Bayamon below Lago Cidra, Rio de .................. 149 near Bayamon ............................. 152-153 Bayamon, Rio Guaynabo near .................... 154-155 Bayaney, Rfo Camuy near ....................... 54-55 Bed material, definition of .......................... 28 Bed load, definition of ............................. 33 Bed load discharge, definition of ...................... 33 Biochemical oxygen demand, definition of ...................................... 28 Biomass, definition of ............................. 28 Blanca at El Jagual, Quebrada .................... 188-194 Blanco at La Tone, Rio ........................... 411 Blanco basin, Rio, gaging station records in ............................. 308-309 Blasina near Carolina, Quebrada .................. 184-185 Blue-green algae, definition of ....................... 32 Bonne Resolution Gut at Bonne Resolution, St Thomas, VI ..................... 480 Borinquen, Rio Turabo above .................... 207-208 Bottom material, definition of ........................ 28 Bucani at Highway 14 bridge near Ponce, Rio ................................. 352 at Ponce .................................... 406 Bucani basin, Rio, gaging station records in ............................. 347-352 low-flow partial-record stations in ............... 405-406 water-quality records in ....................... 350-351 Bucarabones near Las Marias, Rio .................... 412 Cabo Rojo, Rio Viejo near ......................... 410 Caguas, Lago Lofza No. 4 near mouth near .................................. 416-418 Caguas, Rio Bairoa at Bairoa near ................. 226-227 Caguas, Rio Bairoa near ........................ 228-229 Caguas, Rio Caguitas at Highway 30 at ............ 224-225 Caguas, Rio Caguitas at Villa Blanca at ............. 222-223 Caguas, Rio Grande de Loiza at ................. 209-219 Caguitas at Highway 30 at Caguas, Rio ............. 224-225 at Villa Blanca at Caguas ..................... 222-223 near Aguas Buenas .......................... 220-221 Cain near San German, Rio ........................ 409 Campo Rico, Rio Canovanas near ................. 286-287 Camuy basin, Rio, gaging station records in ............................... 52-57 Camuy near Bayaney, Rio ....................... 54-55 at Ties Pueblos Sinkhole ....................... 52-53 near Hatillo ................................ 56-57 Canal Principal de Diversiones at Lago de Guajataca ......................... 46-48 Canovanas near Campo Rico, Rio ................ 286-287 Canas at Magueyes, Rio ........................... 406 at Rfo Canas .............................. 265-276 at Rio Canas Abajo ............................ t 413 at Rio Canas Arriba ............................ 413 downstream from Las Ameiicas Ave ................ 406 near Juana EMaz ............................... 404 near Santa Isabel .............................. 404 Canas basin, Rfo, low-flow partial- record stations in ............................ 404 Caonillas above Lago Caonilks near Jayuya, Rio .............................. 65-66 Caonillas, Lago Caonillas at ......................... 67 Carolina, Quebrada Blasina near .................. 184-185 Casei near Mayaguez, Rfo ......................... 413 Castaner, Lago Guayo near ......................... 386 Catano, Rio Hondo at Flood Channel near .................................. 146-147 Cayaguas at Cerro Gordo, Rio .................. 203-204 Cayey, Lago Carite No. 1 near dam near .................................. 419-425 Cayey, Lago Carite No. 3 on Rio de la Plata near ............................. 416-418 Ceiba, Rio Tallaboa near Quebrada ................... 407 512 INDEX Page Cells/volume, definition of .......................... 28 Central Cambalache, Rio Grande de Arecibo at ............................. 83-84 Central Guamanf, Rio Seco near ..................... 402 Central Rufina, Rio Guayanilk at ................. 359-360 Central Rufina, Rio Guayanilk near ............ 359-360,408 Cerrillos above Lago Cerrillos near Ponce, Rio ............................ 347-348 near Ponce ............................... 349-351 upstream from Lago Cerrillos ..................... 405 Cerro Gordo, Quebrada Cerro Gordo near .................................... 412 Cerro Gordo, Rio Cayaguas at ................... 203-204 Charco Hondo, Rio Tanami at ....................... 82 Chemical oxygen demand, definition of ...................................... 28 Chico at Providencia, Rio, ....................... 323-324 Chico basin, Rio, water-quality records in ............................. 323-324 Chiquito at Portugues, Rio ......................... 406 near Ponce .................................. 406 Chlorophyll, definition of .......................... 29 Ciales, Rio Cialitos at Highway 649 at .................................. 99-100 Ciales, Rio Grande de Manati at ................... 95-% Ciales, Rio Grande de Manati at Highway 149 at.......................... 97-98 Cialitos at Highway 649 at Ciales, Rio ................................. 99-100 Cibuco at Vega Baja, Rio ...................... 111-113 below Corozal ............................ 108-110 Cibuco basin, Rio gaging-station records in ............................. 108-111 ground-water records in ...................... 435-438 water-quality records in ...................... 109-113 Cidra, Lago de Cidra at Damsite near ................. 148 Cimarrona near Jobos, Quebrada ..................... 402 Coamo basin, Rio, low-flow partial- record stations in ........................ 403-404 water-quality records in ...................... 332-333 Coamo at Baftos de Coamo, Rio ..................... 404 at Coamo ................................... 403 near Coamo .............................. 332-333 near Paste ................................... 403 near Santa Isabel .............................. 404 Coamo, Quebrada Monteria near ..................... 403 Coamo, Rib Cuyon near ........................... 403 Coamo, Rio de la Mina at ......................... 404 Coamo, Rio de la Mina near ........................ 403 Coamo, Rio del Pasto near ......................... 403 Collorcs, Quebrada Indalecia at ...................... 405 Collores, Rio Guayo near .......................... 405 Collores, Rio Guayo upstream from Diversion at .............................. 405 Color unit, definition of ............................ 29 Comerio, Rio de La Plata at ..................... 120-130 Comerio, Rio de La Plata near ................... 131-132 Contents, definition of ............................. 29 Control, definition of .............................. 29 Control structure, definition of ....................... 29 Cooperation .................................... 2 Page Corozal, Rio Cibuco below ...................... 108-110 Crest-stage station, definition of ...................... 29 Crest-stage partial-record stations, discharge at ................................ 414 Cruces near Sabana Grande, Rio ..................... 409 Cubic foot per second, definition of .................... 29 Cubic foot per second-day, definition of ................. 29 Cubic feet per second per square mile, definition of ................................. 29 Culebra basin, Rio, low-flow partial- record stations in ............................ 413 Culebra near Aguada, Rio .......................... 413 Culebrinas at Highway 404 near Moca, Rio ............. 398 near Aguada .............................. 399-400 near San Sebastian .......................... 396-397 Culebrinas basin, Rio, gaging station records in ............................ 398 ground-water records in ....................... 477-478 water-quality records in ....................... 396-400 Cupeyes near San German, Rio ...................... 409 Cuyon at La Guava, Rio ........................... 403 near Coamo .................................. 403 D Daguey near Anasco, Rio .......................... 413 Damsite, Lago El Guineo at ......................... 91 Damsite, Lago Lofza at ........................... 278 Damsite, Lago La Plata at ......................... 137 Damsite, Lago Lucchetti at ......................... 361 Damsite, Lago Matiullas at.......................... 92 Damsite, Rio Grande de Loiza below ............... 279-283 Definition of terms ............................ 27-36 Descalabrado basin, Rio, gaging station records in ............................ 334 lovHftow partial-record stations in .................. 404 Descalabrado at Las Oiks, Rio ...................... 404 near Los Llanos ............................... 334 near Sanja Blanca .............................. 404 near Santa Isabel .............................. 404 Diatoms, definition of ............................. 32 Discharge at crest-stage partial- record stations .............................. 414 Discharge at low-flow partial-record stations ................................ 401-413 Discharge at partial-record stations in Puerto Rico ........................... 401-414 Discharge, definition of ............................ 29 Dissolved, definition of ............................ 29 Dissolved-solids concentrations ....................... 29 Diversity index, definition of ........................ 29 Drainage area, definition of ......................... 30 Drainage basin, definition of ......................... 30 Dry mass, definition of ............................. 28 Duey at Duey, Rio ............................... 408 near Rosario ................................. 409 E El Espino, Rio Grande de Anasco at .................. 412 El Espino, Rio Humata near ........................ 412 513 INDEX Page El Mang6, Rio Gurabo below .................... 230-241 El Sefiorial, Rio Piedras at ...................... 158-165 El Verde, Quebrada Sonadora near ................ 290-291 El Veide, Quebrada Toronja at ................... 292-293 El Verde, Rfo Grande near ...................... 297-298 Espfritu Santo basin, Rio, gaging station records in ........................ 290-298 water-quality records in ...................... 295-296 Espfritu Santo near Rio Grande, Rio ............... 294-296 Explanation of records ............................. 9 Fajardo below Fajardo, Rio ...................... 306-307 near Fajardo .............................. 303-305 Fajardo basin, Rio, gaging station records in ................................ 303 water-quality records in ...................... 304-307 Fecal coliform bacteria, definition of ...................................... 28 Fecal streptococcal bacteria, definition of ............................... 28 Flores near Sabana Grande, Rio ..................... 409 Florida, Rio Grande de Arecibo below Lago Dos Bocas near ...................... 68-69 Gage-height, definition of ........................... 30 Gaging station, definition of ......................... 30 Grande basin, Rio, low-flow partial- record stations in ........................... 413 Grande de Anasco basin, Rio, gaging station records in ........................ 386-389 low-flow partial-record stations in ............... 411-413 water-quality records in ...................... 387-393 Grande de Anasco at Anasco Arriba, Rio ............... 413 at El Espino ................................. 412 near Anasco .............................. 392-393 near Lares ............................. 387*388,411 near Las Marias ............................... 412 near San Sebastian .......................... 389-391 Grande de Arecibo at Central Cambalache, Rio ......................... 83-84 above Arecibo .............................. 70-71 below Lago Dos Bocas near Florida .............. 68-69 near Adjuntas .............................. 60-61 near Utuado ............................... 62-63 Grande de Arecibo basin, Rio, gaging station records in ......................... 64-82 ground-water records in ......................... 430 water-quality partial-record stations, analyses of samples collected at ............................ 416-422 water-quality records in ....................... 60-84 Grande de Loiza at Caguas, Rio .................. 209-219 at Highway 183 near San Lorenzo ............... 205-206 at Quebrada Arenas ......................... 186-187 below Damsite ............................ 279-283 below Tmjillo Alto ......................... 284-285 Page Grande de Loiza basin, Rio, gaging station records in ......................... 186-287 ground-water records in .......................... 454 water-quality partial-record stations, analyses of samples collected at ............................. 416-425 water-quality records in ....................... 184-285 Grande de Manati at dales, Rio ................... 95-96 at Highway 2 near Manati ..................... 101-104 at Highway 149 at Ciales ...................... 97-98 near Morovis ............................... 88-90 Grande de Manati basin, Rio, gaging station records in ......................... 88-101 ground-water records in ....................... 431-434 water-quality records in ....................... 86-104 Grande de Patillas near Patfflas, Rio ............... 325-327 Grande de Patillas basin, Rio, gaging station records in ....................... 325 water-quality records in ....................... 326-327 Grande near Rincon, Rio .......................... 413 near El Verde .............................. 297-298 near Sabana Grande ............................ 409 Grande near Lago Lucchetti Damsite, Quebrada .................................. 408 Grande upstream from Lago Loco, Quebrada .................................. 408 Graphs: Ground-water levels at selected wells in Puerto Rico and the U.S. Virgin Islands ............................ 7 Monthly-mean discharge of selected streams in Puerto Rico ......................... 4 Green algae, definition of ........................... 32 Grid showing system for numbering wells and miscellaneous sites (latitude and longitude) ......................... 18 Ground-water level, records of .................... 25-26 Ground-water quality, records of ...................... 26 Ground-water records for Puerto Rico .............. 427-478 Ground-water records for U.S. Virgin Islands ................................... 510 Ground-water station, definition of .................... 30 Ground-water stations in Puerto Rico, map showing location of ........................ 15 Ground-water stations in U.S. Virgin Islands, map showing location of .................. 17 Guaba near Las Marias, Rio ........................ 412 near Maricao ................................. 412 Guadiana at Guadiana, Rio ...................... 133-134 near Naranjito ............................. 135-136 Guajataca above mouth near Quebradillas, Rfo .......................... 49-50 at Lares ................................... 44-46 Guajataca basin, Rio, gaging station records in .................................. 44 ground-water records in ....................... 428-429 water-quality partial-record stations, analyses of samples collected at ............... 416-425 water-quality records in ........................ 45-60 514 INDEX Page Guana'bana near Juana Dfaz, Quebrada ................. 405 Guanajibo at Highwary 119 at San German, Rfo .................................... 366 at La Pica ................................... 409 below San German ............................ 409 near Hormigueros .......................... 380-382 near San German ........................... 367-368 Guanajibo basin, Rfo, gaging station records in ............................. 366-380 ground-water records in ......................... 476 low-flow partial-record stations in .................................. 409-410 water-quality records in ...................... 367-382 Guanajibo, Quebrada Maga near ..................... 410 Guanajibo, Rio Hondo near ........................ 410 Guanica, Rfo Loco at .......................... 362-363 Guayands above mouth at Playa de Guayanes.Rfo.......................... 318-319 at Yabucoa ............................... 316-317 near Penuelas ................................ 407 Guayands basin, Rfo, water-quality records in ............................. 316-319 GuayaniUa at Central Rufina, Rfo ................. 359-360 at Pasto .................................... 408 near Central Rufina ............................ 408 near GuayaniUa ............................... 358 Guayanilla basin, Rfo, gaging station records in ........................... 358 low-flow partial-record stations in ..................................... 408 water-quality records in ..................... 359-360 Guaynabo near Bayamon, Rfo .................... 154-155 Guayo at Guayo, Rfo ............................. 411 near Collores ................................. 405 upstream from Diversion at Collores ................ 405 Guilatte near Adjuntas, Rfo ........................ 411 Guinea Gut at Bethany, St. John, VI .................. 482 Gurabo at Gurabo, Rfo ......................... 255-262 below El Mang6 ........................... 230-241 near Gurabo .............................. 263-264 Gurabo, Quebrada Mamey near ................... 253-254 H Hardness, definition of ............................. 30 Hatillo, Rfo Camuy near ......................... 56-57 Hato Rey, Rfo Piedras at ....................... 176-178 Hoconuco (Duey) near San German, Rfo ............... 409 Hoconuco near San German, Rfo ..................... 409 Hondo at Flood Channel near Catano, Rfo ................................. 146-147 near Guanajibo ............................... 410 Hondo basin, Rfo, low-flow partial- record stations in ........................... 410 water-quality records in ...................... 146-147 Hormigueros, Rfo Guanajibo near ................. 380-382 Hormigueros, Rfo Rosario at Hwy 2 near .................................... 410 Hormigueros, Rfo Rosario near ................ 369-379,410 Humacao at Highway 3 at Humacao, Rfo ............ 314-315 at Las Piedras ............................. 312-313 Page Humacao basin, Rfo, gaging station records in .............................. 312-313 water-quality records in ....................... 314-315 Humata near El Espino, Rfo ........................ 412 Hydrologic Bench-Mark Network, definition of ................................. 30 Hydrologic conditions, summary of ................... 3-8 Hydrologic unit, definition of ........................ 30 Icacos near Naguabo, Rfo ....................... 308-309 Identification numbers, stations ....................... 9 loabon at Real Abajo, Rfo ......................... 346 Inabon at Real Anon, Rfo .......................... 405 Inab6n basin, Rfo, gaging station records in ................................. 346 low-flow partial-record stations in .................. 405 Indalecia at Collores, Quebrada ...................... 405 Indiera Alta, Rfo Prieto at.......................... 411 Ingenio at Jaguey, Rfo ............................ 413 near Aguada ................................. 413 Ingenio basin, Rfo, low-flow partial- record stations in ............................ 413 Instantaneous discharge, definition of ................... 29 Introduction .................................... 1 Jacaguas at Juana Dfaz, Rfo ..................... 342-343 at Vfflaba ................................... 404 Jacaguas basin, Rfo, gaging station records in .............................. 335-343 low-flow partial-record stations in ............... 404-405 water-quality records in ....................... 336-341 Jagual, Quebrada Blanca at El.................... 188-194 Jaguey, Rfo Ingenio at ............................ 413 Jajome at Jajome, Rfo ............................ 402 Jayuya, Rfo Caonillas above Lago Caonillas near ............................ 65-66 Jayuya, Rfo Saliente at Coabey near ................... 64 Jauca, Rfo Jueyes near ............................ 403 Jobos, Quebrada Cimarrona near ..................... 402 Jobos, Quebrada Melania near ....................... 402 Jolly Hill Gut at Jolly Hill, SL Croix, VI ............................... 484 Josefina at Pinero Avenue, Quebrada ............... 179-180 Juana Dfaz, Quebrada Guan&bana near ................. 405 Juana Dfaz, Rfo Canas near ........................ 404 Juana Dfaz, Rfo Jacaguas at ..................... 342-343 Jueyes at Rfo Jueyes, Rfo .......................... 403 near Jauca ................................... 403 Jueyes basin, Rfo, low-flow partial- record stations in ............................ 403 Juncos, Rfo Valenciano near ..................... 242-252 Lago Caonillas at Caonillas ......................... 67 Lago Carite at Gate Tower ......................... 116 515 INDEX Page Lago Carite No. 1 near dam near Cayey ............ 419-425 No. 3 on Rfo de La Plata near Cayey ............................... 416-418 Lago Cerrillos near Ponce, Rfo Cerrillos above ......................... 347-348 Lago Cerrillos, Rfo Cerrillos upstream from ............................. 405 Lago Cerrillos, Rfo San Patricio upstream from ............................. 405 Lago de Cidra at Damsite near Cidra .................. 148 Lago de Guajataca, Canal Principal de Diversiones at......................... 47-48 No. 1 near dam near Quebradillas ............... 419-425 No. 3 near mouth near Quebradillas ........................... 416-418 Lago Dos Bocas No. 1 near dam near Utuado ............................... 419-422 No. 3 at west branch near Utuado ............... 416-418 Lago el Guineo at Damsite .......................... 91 Lago Garzas No. 1 near dam near Adjuntas .............................. 419-422 Lago Guayo near Castafier ......................... 386 Lago La Plata at Damsite .......................... 137 Lago La Plata No. 3 near dam near Naranjito ............................. 419-425 No. 5 near mouth near Naranjito ................ 416-418 Lago Loco, Quebrada Grande upstream from ............................. 408 Lago Loco, Rfo Loco upstream from .................. 408 Lago Loiza at Damsite ........................... 278 No. 4 near mouth near Caguas ................. 416-418 No. 7 near dam near TrujiUo Alto ................................. 419-425 Lago Lucchetti at Damsite ......................... 361 Lago Lucchetti Damsite, Quebrada Grande near .............................. 408 Lago Lucchetti Damsite, Rf e Naranjo near .................................... 408 Lago Lucchetti Damsite, Rfo Yauco near .................................... 408 Lago Matrullas at Damsite .......................... 92 Lago Toa Vaca, Rfo Toa Vaca above .............. 335-341 Lago Toa Vaca, Rfo Toa Vaca upstream from............................. 405 La Guava, Rfo Cuyon at........................... 403 Laguna San Jos£ No. 2 at San Juan ................... 181 Laguna Tortuguero basin, water- quality records in .......................... 105 Laguna Tortuguero outlet near Vega Baja ............................... 105 Lajas near Maricao, Rfo ........................... 411 Land-surface datum, definition of ..................... 30 Lapas near Rabo del Buey, Rfo ................... 330,402 La Pica, Rfo Guanajibo at.......................... 409 La Plata at Proyecto La Plata, Rfo de ............................... 117-119 at Comerio ............................... 120-130 at Hwy 2 near Toa Alta ...................... 139-143 below La Plata Dam ........................... 138 near Comerfo ............................. 131-132 Page La Plata basin, Rfo de, gaging station records in ......................... 116-140 ground-water records in ....................... 439-441 water-quality partial-record stations, analyses of samples collected at ............................. 416-425 water-quality records in ....................... 118-143 Lares, Rfo Grande de Afiasco near ............................... 387-388,411 Lares, Rfo Guajataca at ......................... 44-46 Las Ameiicas Ave., Rfo Gagas downstream from ............................ 406 Las Canas at Perchas, Quebrada ..................... 412 Las Marias, Rfo Arenas at ......................... 412 Las Marias, Rfo Bucarabones near .................... 411 Las Marias, Rfo Grande de Afiasco near ............... 412 Las Marias, Rfo Guaba near ........................ 412 Las Marias, Rfo Mayaguecilla at ..................... 412 Las Ollas, Rfo Descalabrado at ...................... 404 Las Piedras, Rfo Humacao at .................... 312-313 Las Vegas, Rfo Rosario at ......................... 410 La Tone, Rfo Blanco at ........................... 411 Levels for Puerto Rico, ground water ............................ 427-478 Levels for U.S. Virgin Islands, ground water ............................ 485-510 Limani near Yahuecas, Rfo ......................... 411 Lizas, Rfo Maunabo at ............................ 320 Loco at Guanica, Rfo .......................... 362-363 Loco basin, Rfo, low-flow partial-record stations in ....................... 408 water-quality records in ....................... 362-363 Loco upstream from Lago Loco, Rfo .................. 408 Los Llanos, Rfo Descalabrado near ................... 334 Los Platanos at Marisol, Quebrada de ............................... 411 Low-flow partial-record stations, Discharge at............................. 401-413 Low-flow partial-record in Southwest Puerto Rico, map showing location of ........................... 14 M Macani at Magas Arriba, Rfo ....................... 407 near Pefiuelas ................................. 407 Macani basin, Rfo, low-flow partial-record stations in ....................... 407 Maga basin, Quebrada, low-flow partial-record stations in ....................... 410 Maga near Honnigueros, Quebrada ................... 410 Magas Arriba, Rfo Macan* at ....................... 407 Magueyes, Rfo Canas at .......................... 406 Majada at La Plena, Rfo ........................ 331,402 at Rabo del Buey .............................. 402 Mamey near Gurabo, Quebrada ................... 253-254 near Sabana ............................... 299-300 Mameyes basin, Rfo, gaging station records in .............................. 299-300 Manatf, Rfo Grande de Manatf at Highway 2 near .......................... 101-104 516 INDEX Page Maps: Location of surface-water stations in Puerto Rico .............................. 12 Location of ground-water stations in Puerto Rico .............................. IS Location of ground-water stations in file U.S. Virgin Islands ...................... 17 Location of low-flow partial-record stations in Southwest Puerto Rico ................ 14 Location of maximum concentration of fecal coliform bacteria at sample sites ............................... 10 Location of maximum concentration of fecal streptococci bacteria at sample sites ............................. 11 Location of surface-water stations in fiie U.S. Virgin Islands ...................... 16 Location of water-quality stations in Puerto Rico .............................. 13 Rio Camuy basin ............................... 51 Rfo Cibuco basin .............................. 107 Rio Culebrinas basin ........................... 395 Rfo Grande de Arecibo basin ...................... 59 Rfo Grande de Lofza basin ....................... 183 Rio Grande de Manati basin ....................... 85 Rfo Guajataca basin ............................. 43 Rfo Guanajibo basin ........................... 365 Rfo Hen-era to fiie Rfo Anton Ruiz basins ................................... 289 Rfo Hondo to fiie Rfo Puerto Nuevo basins ............................. 145 Rfo Humacao to the Rfo Seco basins ................................... 311 Rfo Inabon to fiie Rfo Loco basins ................. 345 Rfo de la Plata basin ........................... 115 Rfo Salinas to fiie Rfo Jacaguas basins................................... 329 Rfo Yaguez and the Rfo Grande de Anasco basins ................................ 383 Maricao at Maricao, Rfo ........................... 410 Maricao, Rfo Guaba near .......................... 412 Maricao, Rfo Lajas near ........................... 411 Marisol, Quebrada de Los Pl&anos at ................. 411 Matilde basin, Rfo, low-flow partial-record stations in ................... 406-407 Matilde at Ponce, Rfo ............................ 407 Maunabo at Lizas, Rfo ............................ 320 at Maunabo ............................... 321-322 Maunabo basin, Rfo, gaging stations records in ................................ 320 water-quality records in ................... 321-322 Maximum concentrations of fecal coliform bacteria at sampled sites, map showing location of .................. 10 Maximum concentrations of fecal streptococci bacteria at sampled sites, map showing location of ................................ 12 Mayaguecilla at Las Marias, Rfo ..................... 412 Mayaguez, Quebrada Sabalos near .................... 410 Mayaguez, Rfo Casei near ......................... 413 Page Mayaguez, Rfo Yaguez near ..................... 384-385 Mean concentration, definition of ..................... 34 Mean discharge, definition of ........................ 29 Measuring point, definition of ........................ 30 Melanfa basin, low-flow partial-record stations in ....................... 402 Melanfa near Jobos, Quebrada ....................... 402 Metamorpbic stage, definition of ...................... 30 Methylene blue active substances, definition of ................................. 30 Micrograms per gram, definition of .................... 30 Micrograms per liter, definition of ..................... 30 Milligrams of carbon per area or volume per unit time or periphyton and macrophytes and for phytoplankton, definition of ................... 33 Milligrams of oxygen per area or volume per unit time for periphyton and macrophytes and for phytoplankton, definition of ................... 33 Milligrams per liter, definition of ..................... 30 Mina at Coamo, Rfo de la ......................... 404 near Coamo .................................. 403 Moca, Rfo Culebrinas at Highway 404 near ..................................... 398 Monteria near Coamo, Quebrada ..................... 403 Morovis, Rfo Grande de Manati near ................ 88-90 N Naguabo, Rfo Icacos near ....................... 308-309 Naranjito, Lago La Plata No. 3 near dam near ........................... 419-425 Naranjito, Lago La Plata No. 5 near mouth near .......................... 416-418 Naranjito, Rfo Guadiana near .................... 135-136 Naranjo near Lago Lucchettt Damsite, Rfo .............. 408 National Stream-Quality Accounting Network, definition of .......................... 31 National Trends Network, definition of ................. 31 Natural substrate, definition of ....................... 34 Networks and programs, special ...................... 9 Organic mass, definition of .......................... 28 Organism, definition of ............................ 31 Organism count/area, definition of ..................... 31 Organism count/volume, definition of .................. 31 Orocovis, Rfo Bauta near ........................ 93-94 Orocovis, Rfo Orocovis near ...................... 86-87 Palomas, Quebrada Susua at ........................ 408 Parameter code, definition of ........................ 31 Partial record station, definition of ................................. 31 Partial-record stations, Discharge at............................. 401-414 517 INDEX Page Partial-record stations in Southwest Puerto Rico, map showing location of low-flow ................... 14 Partial record station in Puerto Rico, Water quality at .................... 415-425 Particle size, definition of ........................... 32 Particle-size classification, definition of ............................... 32 Pastille near Ponce, Rfo ........................... 407 Pastille, Rfo Pastille at ............................ 407 Paste near Coamo, Rio del ......................... 403 Paste, Rfo Coamo near ............................ 403 Paste, Rio Guayanflla at ........................... 408 Patillas, Rfo Grande de Patillas near ............... 325-327 Pedro Garcfa, Rfo Toa Vaca at ...................... 404 Penuelas, Rfo Guayands near ....................... 407 Pefiuelas, Rfo Macan* near ......................... 407 Penuelas, Rfo Tallaboa at .......................... 407 Percent composition, definition of ..................... 32 Perchas, Quebrada Las Canas at ..................... 412 Periphyton, definition of ............................ 32 Pesticides, definition of ............................ 32 Pezuela, Rfo Prieto at............................. 411 Phytoplankton, definition of ......................... 32 Picocurie, definition of ............................. 32 Piedras at HatoRey, Rfo ....................... 176-178 at El Sefiorial ............................. 158-165 at Rfo Piedras ............................. 168-175 near Rfo Piedras ........................... 166-167 Pifiero Avenue, Quebrada Josefma at ............... 179-180 Plankton, definition of ............................. 32 Playa de Guayan£s, Rfo Guayane's above mouth at ......................... 318-319 Playa de Ponce, Quebrada del Agua at ................. 407 Plena, Rfo Majada at La ........................ 331,402 Pdychlorinated biphenyls, definition of ............................... 33 Ponce, Quebrada Ausubo near ....................... 405 Ponce, Rfo Bayagin near .......................... 406 Ponce, Rfo Bucani at ............................. 406 Ponce, Rfo Bucani at Highway 14 near ................ 352 Ponce, Rfo Cenillos above Lago Cenillos near .......................... 347-348 Ponce, Rfo Cenillos near ....................... 349-351 Ponce, Rfo Chiquito near .......................... 406 Ponce, Rfo Matilde at ............................ 407 Ponce, Rfo Pastille near ........................... 407 Ponce, Rfo Portugal at ........................ 356-357 Ponce, Rfo Portugal at Hwy 2 By-Pass at ............................... 406 Ponce, Rfo Portugues near ................... 353-355,406 Portugal at Hwy 2 By-Pass at Ponce, Rfo .............. 406 at Ponce ................................. 356-357 near Ponce ............................ 353-355,406 near Tibes ................................... 406 Portugu£s basin, Rfo, gaging station records in ........................... 353 low-flow partial-record stations in ................................ 406 water-quality records in ...................... 354-357 Portugues, Rfo Chiquito at ......................... 406 Page Prieto at Indiera Alta, Rfo .......................... 411 at Pezuela ................................... 411 at Rfo Prieto ................................. 411 Primary productivity, definition of ..................... 33 Programs, special networks and ...................... 9 Providencia, Rfo Chico at ....................... 323-324 Proyecto La Plata, Rfo de La Plata at ................................ 117-119 Publications on techniques of water-resources investigations ................. 37-39 Puerto Nuevo basin, Rfo, gaging station records in ......................... 158-180 water-quality records in ....................... 160-182 Quality of water records of Puerto Rico, surface- and ........................ 41-400 Quebrada Arenas, Rfo Grande de Loiza at ................................ 186-187 Quebradillas, Lago Guajataca No. 1 near dam near ........................... 419-425 Quebradillas, Lago Guajataca No. 3 near mouth near .......................... 416-418 Quebradillas, Rfo Guajataca above mouth near .............................. 49-50 Rabo del Buey, Rfo Lapas near ................... 330,402 Rabo del Buey, Rfo Majada at ...................... 402 Radiochemical program, definition of .................. 33 Real Abajo, Rfo Inabon at ......................... 346 Real Anon, Rfo Inabon at .......................... 405 Records, explanation of ............................ 9 Records of ground-water levels .................... 25-26 Records of ground-water quality ...................... 26 Records of stage and water discharge ................ 18-21 Records of surface-water quality ................... 21-24 Recoverable from bottom material, definition of ................................. 33 Return period, definition of .......................... 33 Rincon, Rfo Grande near .......................... 413 Rfo Canas Abajo, Rfo Canas at ...................... 413 Rfo Canas Arriba, Rfo Canas at...................... 413 Rfo Canas, Rfo Canas at........................ 265-276 Rfo Grande, Rfo Espfritu Santo near ............... 294-296 Rfo Piedras, Rio Piedras at ...................... 168-175 Rfo Piedras, Rfo Piedras near .................... 166-167 Rfo Prieto at Rfo Prieto ........................... 411 River Gut near Golden Grove, St. Croix,,, .............. 483 Rosario at Hwy 2 near Hormigueros, Rio ............... 410 at Las Vegas ................................. 410 near Hormigueros ........................ 369-379,410 Rosario, Rfo Duey near ........................... 409 Runoff, in inches, definition of ....................... 33 Sabalos basin, Quebrada, low-flow partial-record stations in .... 410 518 INDEX Page S&balos near Mayaguez, Quebrada .................... 410 Sabana basin, Rio, gaging station records in ............................. 301-302 at Sabana ................................ 301-302 Sabana Grande, Rio Graces near ..................... 409 Sabana Grande, Rio Flores near ..................... 409 Sabana Grande, Rio Grande near ..................... 409 Sabana, Rio Mameyes near ...................... 299-300 Saliente at Coabey near Jayuya, Rio ................... 64 Salinas at Salinas, Rio ............................ 403 Salinas basin, Rio, crest-stage, partial-records station in ......................... 414 gaging station records in ...................... 330-331 low-flow partial-record stations in ............................. 402-403 Salinas, Quebrada Yeguas near ...................... 414 Salvatierra near San Lorenzo, Quebrada ............................. 195-202 San German, Rio Cain near ........................ 409 San German, Rio Cupeyes near ...................... 409 San German, Rio Guanajibo at Highway 119 at .................................. 366 San German, Rio Guanajibo near ................. 367-368 San German, Rio Guanajibo below ................... 409 San German, Rio Hoconuco near ..................... 409 San German, Rio Hoconuco (Duey) near ............... 409 Sanja Blanca, Rio Descalabrado near .................. 404 San Juan, Bahia de San Juan No. 5 at ................. 182 San Juan, Laguna San Jos6 No. 2 at .................. 181 San Lorenzo, Quebrada Salvatierra near ............. 195-202 San Lorenzo, Rio Grande de Loiza at Highway 183 near ....................... 205-206 San Patrick) upstream from Lago CerriUos, Rio ............................. 405 San Sebastian, Rio Culebrinas near ................ 396-397 San Sebastian, Rio Grande de Anasco near .................................389-391 Santa Isabel, Rio Canas near ........................ 404 Santa Isabel, Rio Coamo near ....................... 404 Santa Isabel, Rio Descalabrado near .................. 404 Seco basin, Rio, low-flow partial-record stations in ...................... 402 Seco near Central Guamanf, Rio ..................... 402 Sediment, definition of ............................. 33 7-day 10-year low flow, definition of ............................... 34 Sodium-adsorption-ratio, definition of ............................... 34 Solute, definition of ............................... 34 Sonadora near El Verde, Quebrada ................ 290-291 Special network and programs ....................... 9 Specific conductance, definition of .................... 34 Stage-discharge relation, definition of ............................... 34 Station identification numbers ........................ 9 St. Croix, VI, Jolly Hill Gut at Jolly Hill ................................ 484 St. Croix, VI, River Gut near Golden Grove ............................. 483 St. John, VI, Guinea Gut at Bethany .................. 482 Strcamflow, definition of ........................... 34 Page St. Thomas, VI, Bonne Resolution Gut at Bonne Resolution ...................... 480 St. Thomas, VI, Turpentine Run at Mariendal ............................... 481 Substrate, definition of ............................. 34 Summary of hydrologic conditions ................... 3-8 Surface and quality-of-water records for Puerto Rico .......................... 41-400 Surface area, definition of........................... 34 Surface-water quality, records of ................... 21-24 Surface-water records for U.S. Virgin Islands ........................ 479-484 Surface-water stations in Puerto Rico, map showing location of .................... 12 Surface-water stations in U.S. Virgin Islands, map showing location of .................................. 16 Surficial bed material, definition of................................. 34 Suspended, definition of ............................ 35 Suspended-recoverable, definition of ................... 35 Suspended sediment, definition of ..................... 33 Suspended-sediment concentration, definition of................................. 33 Suspended-sediment discharge, definition of ................................. 34 Suspended-sediment load, definition of ................................. 34 Suspended-total, definition of ........................ 35 Susua at Palomas, Quebrada ........................ 408 Tanami at Charco Hondo, Rio ....................... 82 near Utuado ................................ 72-81 Tallaboa basin, Rio, low-flow partial-record stations in ....................... 407 Tallaboa at Penuelas, Rio .......................... 407 at Tallaboa................................... 407 near Quebrada Ceiba ............................ 407 Taxonomy, definition of ............................ 35 Techniques of water-resources investigations, publications on ................. 37-39 Terms, definition of ............................ 27-36 Thermograph, definition of .......................... 35 Tibes, Rio Portugue's near .......................... 406 Time-weighted average, definition of .................. 35 Toa Alta, Rio de La Plata at Highway 2 near .......................... 139-143 Toa Vaca above Lago Toa Vaca, Rio .............. 335-341 at Pedro Garcia ............................... 404 upstream from Lago Toa Vaca ..................... 405 Tons per acre-foot, definition of ...................... 35 Tons per day, definition of .......................... 35 Toronja at El Verde, Quebrada ................... 292-293 Total, definition of ................................ 36 Total coliform bacteria, definition of................................. 28 Total discharge, definition of ........................ 36 Total organism count, definition of ................................. 31 519 INDEX Page Total-recoverable, definition of ....................... 36 Total sediment discharge, definition of ............................... 34 Total-sediment load, definition of ..................... 34 Tres Pueblos Sinkhole, Rio Camuy at ............... 52-53 Tritium network, definition of ........................ 36 TrujUlo Alto, Lago Loiza No. 7 near dam near .......................... 419-425 Trujfllo Alto, Rfo Grande de Loiza below ........................... 284-285 Turabo above Borinquen, Rfo .................... 207-208 Turpentine Run at Mariendal, St Thomas, VI ............................ 481 U Utuado, Lago Dos Bocas No. 1 near dam near ............................. 419-422 Utuado, Lago Dos Bocas No. 3 at west branch near ........................ 416-418 Utuado, Rfo Grande de Arecibo near ................ 62-63 Utuado, Rio Tanam* near ........................ 72-81 Valenciano near Juncos, Rfo ..................... 242-252 Vega Baja, Laguna Tortuguero outlet near ............................... 105 Vega Baja, Rio Cibuco at ....................... 111-113 Viejo near Cabo Rojo, Rio ......................... 410 Villalba, Rio Jacaguas at .......................... 404 W Water-discharge, records of stage and ............... 18-21 Water-quality partial-record stations in Puerto Rico, analyses of samples collected at ............................ 415-425 Water-quality stations in Puerto Rico, map showing location of .................. 13 Water-resources investigations, publications on techniques of ................ 37-39 Water year, definition of ........................... 36 WATSTORE data, Access to ..................... 26-27 WDR, definition of ............................... 36 Weighted average, definition of ....................... 36 Wells - Puerto Rico: Cibuco basin, Rfo WeU 70 - Sabana Hoyos ..................... 435 Well 211 - Rosario No. 3 ..................... 436 Well 212 - Ponderosa TW-1 ................... 437 Well 213 - Pampano No. 2 .................... 438 Culebrinas basin, Rio WeU 83 - San Sebastian ...................... 477 WeU 200 - Aguadilla Cement north .............. 478 Grande de Arecibo basin, Rfo WeU 204 - Gilberto Rivera .................... 430 Grande de Loiza basin, Rfo WeU 222 - Campo Rico TW ................... 454 Page Grande de Manatf basin, Rfo WeU 205 - NC-05 Barceloneta near Cruce Davila .......................... 431 Wen 206 - Plazuela No. 2 ...................... 432 WeU 207 - Cantito La Luisa .................... 433 Wen 210 - Gelo Martfnez ...................... 434 Guajataca basin, Rfo WeU 165 - Mateo Perez, Bo. Salto ................ 428 WeU 202 - Carmelo Barreto-Garcfa ............... 429 Guanajibo basin, Rfo WeU 143 - Vivoni, Hacienda Amistad ................................. 476 Hondo to Rfo Puerto Nuevo basins, Rfo WeU 218 - Levittown No. 7 ..................... 442 WeU 219 - Fort Buchanan No. 1 ................. 443 Wen 220 - Parque San Luis Rey ................. 444 WeU 221 - Hyde Park TW - 10 .................. 445 Wen PN-2 ................................. 446 WeU PN-5 ................................. 447 Wen PN-6 ................................. 448 WeU PN-7 ................................. 449 Wen PN-8c ................................ 450 WeU PN-10 ................................ 451 WeU PN-13 ................................ 452 WeU PN-19 ................................ 453 Humacao to Rfo Seco basins, Rfo Wen 6 - Juana 5 ............................. 455 WeU 96 - USGS TW-2 or Yabucoa 7 ............. 456 InatxSn to Rfo Loco basins, Rfo WeU 132 - Yauco 2 .......................... 475 La Plata basin, Rfo de Wen 214 - Dorado Beach No. 7 .................. 439 WeU 216 - Pozo Navy - Campanulas .............. 440 WeU 217 - Monserrate TW-2 .................. 441 Salinas to Rfo Jacaguas basins, Rfo WeU - 87 Akmar 1 .......................... 457 WeU HW-TW-01 ............................ 458 WeU HW-TW-02 ............................ 459 Wen HW-TW-03 ............................ 460 WeU HW-TW-03C ........................... 461 WeU HW-TW-03E ........................... 462 WeU HW-TW-04 ............................ 463 WeU HW-TW-05B ........................... 464 WeU HW-TW-07 ............................ 465 Wett HW-TW-08 ............................ 466 WeU HW-TW-10 ............................ 467 WeU HW-TW-11 ............................ 468 WeU HW-TW-11C ........................... 469 WeU HW-TW-13 ............................ 470 WeU HW-TW-14 ............................ 471 WeU HW-TW-15 ............................ 472 WeU RM- 05 .............................. 473 WeURM -10 .............................. 474 Wells - U.S. Virgin Islands: StCroix WeU 1 - Fail-plains 6 (FP6) ..................... 486 WeU 2 - USGS-10, Fairplains 2 (FP2) ............. 487 WeU 3 - Golden Grove 6 (PW6) ................. 488 WeU 4 - Golden Grove 1 (PW1) ................. 489 WeU 6 - Adventure 28 ........................ 490 WeU 7 - Concordia 14 ........................ 491 520 INDEX Page Well 8 - Concoidia 1 (main pump house) ........................ 491 Well 9 - Concoidia 7 ....................... 492 Well 10 - Banen Spot 5 (PWD-5) ............... 492 Well 11 - WAPA - 02 ....................... 493 Well 12 - WAPA - 03 ....................... 494 Well 13 - WAPA - 17 ....................... 495 Well 14 - WAPA - 21a ...................... 496 Well 15 - WAPA - 23a ...................... 497 SL John Well 1 - NPS-2 (Cruz Bay) ................... 502 WeU 2 - NPS-5 (Trunk Bay) .................. 502 Wen 3 - NPS-6 (Cinnamon Bay) ............... 503 Wen 5 - DPW-6 .......................... 504 Wen 6 - DPW-5 .......................... 505 Wen 7 - DPW-4 .......................... 505 Wen 8 - DPW-3 .......................... 505 WeU 9 - DPW-2 .......................... 506 WeU 10 - DPW-1 .......................... 506 WeU 11 - Guinea Gut WeU ................... 507 WeU 12 - VIEO-2 .......................... 508 WeU 13 - VIEO-3 .......................... 509 WeU 14 - VIEO-4 .......................... 510 SL Thomas WeU 1 - USGS-8 (Thatch Farm Dudovick) .................... 498 WeU 2 - Mahogany 15 ...................... 498 Wen 3 - Mahogany 16 ...................... 498 WeU 4 - Mahogany 17 ...................... 499 WeU 5 - Donoe 3 .......................... 499 WeU 6 - Grade School 3 ..................... 500 WeU 7 - VIEO-1 ........................... 501 Page Wet mass, definition of ............................ 28 WSP, definition of ............................... 36 Yabucoa, Rio Guayane* at ...................... 316-317 Yaguez at Balboa, Rio ............................ 410 near Mayaguez ............................. 384-385 Yaguez basin, Rio, low-flow partial-record stations in ....................... 410 water-quality records in ....................... 384-385 Yahuecas, Rio Limani near ......................... 411 Yauco basin, Rio, gaging station records in ................................. 361 low-flow partial-record stations in .................. 408 Yauco near Lago Lucchetti Damsite, Rio ............... 408 Yeguas near Salinas, Quebrada ...................... 414 Zooplankton, definition of .......................... 32 *U.S. GOVERNMENT PRINTING OFFICE 1992-0-673-207/50031 October 1, 1978 FACTORS FOR CONVERTING INCH-POUND UNITS TO INTERNATIONAL SYSTEM UNITS (SI) The following factors may be used to convert the inch-pound units published herein to the International System of Units (SI). Multiply inch-pound units inches (in) feet (ft) miles (mi) acres square miles (mi2 ) gallons (gal) million gallons cubic feet (ft3 ) cfs-days acre-feet (acre-ft) cubic feet per second (ft3 /s) gallons per minute (gal/min) million gallons per day tons (short) By Length 2.54xlO! 2.54xia2 3.048xlO- f 1.609x10° Area 4.047x103 4.047X10- 1 4.047x10~3 2.590x10° Volume 3.785x10° 3.785x10° 3.785xia3 3.785xl03 3.785xl(r3 2.832x101 2.832x10-* 2.447x103 2.447x10~3 1.233xl03 1.233xlO~3 1.233x1 a6 flow 2.832xlO! 2.832xlO! 2.832xl(r2 6.309xia2 6.309x10~2 6.309xl(r5 4.38U10 1 4.381xia2 Mass 9.072X10" 1 To obtain SI units millimeters (mm) meters (m) meters (m) kilometers (km) square meters (m2 ) square hectometers (hm2 ) square kilometers (km2 ) square kilometers (km2 ) liters (L) cubic decimeters (dm3 ) cubic meters (m3 ) cubic meters (m3 ) cubic hectometers (hm3 ) cubic decimeters (dm3 ) cubic meters (m3 ) cubic meters (m3 ) cubic hectometers (hm3 ) cubic meters (m3 ) cubic hectometers (hm3 ) cubic kilometers (km3 ) liters per second (L/s) cubic decimeters per second (dm3 /s) cubic meters per second (m3 /s) liters per second (L/s) cubic decimeters per second (dm3 /s) cubic meters per second (m3 /s) cubic decimeters per second (dm3 /s) cubic meters per second (m3 /s) megagrams (Mg) or metric tons / U.S. DEPARTMENT OF THE INTERIOR U.S. Geological Survey P.O. Box 364424 San Juan, Puerto Rico 00936-4424 OFFICIAL BUSINESS PENALTY FOR PRIVATE USE $300 SPECIAL 4th CLASS BOOK RATE J j