Water Resources Data Puerto Rico and the U.S. Virgin Islands ciZOLOGIC,qt Water Year 1987 cfr Ci"C S E P 1 St Thomas I Isla cle 3 St John I Culebra VIRGIN Isla de Vieques ISLANDS PUERTO RICO Saint Croix I U.S. GEOLOGICAL SURVEY WATER-DATA REPORT PR-87-1 Prepared in cooperation with the Commonwealth of Puerto Rico and with other agencies CALENDAR FOR WATER YEAR 1987 1986 OCTOBER NOVEMBER DECEMBER SMTW TF S SMTW TF S SMTW TF S 1 2 3 4 1 1 2 3 4 5 6 5 6 7 8 9 10 11 2 3 4 5 6 7 8 7 8 9 10 11 12 13 12 13 14 15 16 17 18 9 10 11 12 13 14 15 14 15 16 17 18 19 20 19 20 21 22 23 24 25 16 17 18 19 20 21 22 21 22 23 24 25 26 27 26 27 28 29 30 31 23 24 25 26 27 28 29 28 29 30 31 30 1987 JANUARY FEBRUARY MARCH SMTW TF S SMTW TF S SMTW TF S 1 2 3 1 2 3 4 5 6 7 1 2 3 4 5 6 7 4 5 6 7 8 9 10 8 9 10 11 12 13 14 8 9 10 11 12 13 14 11 12 13 14 15 16 17 15 16 17 18 19 20 21 15 16 17 18 19 20 21 18 19 20 21 22 23 24 22 23 24 25 26 27 28 22 23 24 25 26 27 28 25 26 27 28 29 30 31 29 30 31 APRIL MAY JUNE SMTWTF S SMTW TF S SMTW TF S 1 2 3 4 1 2 1 2 3 4 5 6 5 6 7 8 9 10 11 3 4 5 6 7 8 9 7 8 9 10 11 12 13 12 13 14 15 16 17 18 10 11 12 13 14 15 16 14 15 16 17 18 19 20 19 20 21 22 23 24 25 17 18 19 20 21 22 23 21 22 23 24 25 26 27 26 27 28 29 30 24 25 26 27 28 29 30 28 29 30 31 JULY AUGUST SEPTEMBER SMTWTF S SMTW TF S SMTW TF S 1 2 3 4 1 1 2 3 4 5 5 6 7 8 9 10 11 2 3 4 5 6 7 8 6 7 8 9 10 11 12 12 13 14 15 16 17 18 9 10 11 12 13 14 15 13 14 15 16 17 18 19 19 20 21 22 23 24 25 16 17 18 19 20 21 22 20 21 22 23 24 25 26 26 27 28 29 30 31 23 24 25 26 27 28 29 27 28 29 30 30 31 Water Resources Data Puerto Rico and the U.S. Virgin Islands Water Year 1987 by R.E. Curtis, Jr.., Z, Aquino, P.L. Diaz, and R. Vachier Isla d? Culebra Isla de Vieques PUERTO RICO St Thomas I c°Z. 04i1 St John I VIRGIN ISLANDS Saint Croix I U.S. GEOLOGICAL SURVEY WATER-DATA REPORT PR-87-1 Prepared in cooperation with the Commonwealth of Puerto Rico and with other agencies 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 GPO Box 4424 San Juan, PR 00936 (Telephone: (809) 749-4346) iii 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 person­ nel 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. The data included in this report was collected under the supervision of Eloy Colon-Dieppa. 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: Jose M. Agis Senen Guzman-Rios George Arroyo Karl G. Johnson Angel Class-Cacho Sandra Lagares Iris M. Concepci6n Ana V. Sanchez Carlos Figueroa Jose Rene Sanchez Javier Garcia Luis Santiago-Rivera Rend Garcia Luis Soler Ralph Gonzalez Jose A. Torres Evelyn S. Guevara Heriberto Torres-Sierra 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 Allen L. Zack, District Chief, Caribbean District, San Juan, Puerto Rico. 50272- t01 REPORT DOCUMENTATION i 1. REPORT NO. 3. Recipient's Accession No. PAGE USGS/WRD/HD-89/266 4. Trtle end Subtitle S. Report Oat* Water Resources Data for Puerto Rico and the U.S. Virgin May 1989 Islands, Water Year 1987 R. 7. Auttior(s) Russell E. Curtis, Jr., Zaida Aquino, S. Perfortrung Orgaruzetion Rept No. Ricardo J. Vachier, Pedro L. Diaz USGS-WDR-PR-87-1 9. Performing Organization Name and Address • 10. Pronect/Tesli/Work Unit 14e. U.S. Geological Survey, Water Resources Division G.P.O. Box 4424 II. Contrect(C) or Cerierff(G) No. San Juan, Puerto Rico 00936 CO (GI 12. Sponsoring Organization Name and Address 13. Type of Report & Ported Cowered U.S. Geological Survey, Water Resources Division Annual-Oct. 1, 1986 G.P.O. Box 4424 to Sept. 30, 1987 San Juan, Puerto Rico 00936 14. 15. Supp4ementary Notes Prepared in cooperation with the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands and other agencies. 16.. Abstract (Limit: 200 words) Water-resources data for surface-water, quality-of-water, and ground-water records for the 1987 water year for Puerto Rico and the U.S Virgin Islands, consists of records of discharge, water quality of streams, and water levels of wells, This report contains discharge records for 49 streamflow-gaging stations, and 1 crest-stage, partial-record streamflow stations; water quality records-for 16 streamflow-gaging stations, 42 ungaged streamsites, 11 lake sites, 1 lagoon, and 1 bay; and water-level records for 56 observation wells. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating local and federal agencies in Puerto Rico and the U.S. Virgin Islands. 17. Document Analysis e. Descriptors *Surface water, *Water quality, *Ground water, Aquifers, Chemical analysis, Gaging Stations, Hydrologic data, Sediments, Streamflow, Water analysis, Water Levels, Lakes. b. Iderrtifiers/Open-Endiro Terms Puerto Rico, U.S. Virgin Islands, Sampling sites. c. COSATI Fieie/Groun 12. Availability Statemen. 19. Security Class (This Report) 21. No. of Pages 370 NO RESTRICTION ON DISTRIBUTION UNCLASSIFIED 20. Security Crass (This Page) 22. Price UNCLASSIFIED (S.. ANSI-7-39.18) S.. Instructions on Reverse OPTIONAL FORM 272 1e-77) (Formerly NTIS-3S) Department of Commerce V CONTENTS Page Preface iii List of surface-water and water-quality stations, in downstream List of ground-water wells, by basin, for which records are order, for which records are published viii published xii Introduction 1 Cooperation 2 Summary of hydrologic conditions 2 Precipitation 2 Surface water 3 Ground water 5 Water quality 8 Special networks and programs 9 Explanation of records 9 Station identification numbers 12 Downstream order system 12 Latitude-longitude system 12 Records of stage and water discharge 18 Data collection and computation 18 Data presentation 20 Identifying estimated daily discharge 23 Accuracy of the records 23 Records of surface-water quality 23 Classification of records 24 Arrangement of records 24 On-site measurements and sample collection 24 Water temperature 25 Sediment 26 Laboratory measurements 26 Data presentation 26 Remark codes 28 Records of ground-water levels 28 Data collection and computation 28 Data presentation 29 Records of ground-water quality 30 Data collection and computation 30 Data presentation 31 Access to WATSTORE data 31 Definition of terms 32 Publications on Techniques of Water-Resources Investigations 46 Surface- and quality-of-water records for Puerto Rico 49 Discharge at partial-record stations in Puerto Rico 275 Water-quality at partial-record stations in Puerto Rico 279 Ground-water records for Puerto Rico 295 Surface-water records for the U.S. Virgin Islands 329 Ground-Water records for the U.S. Virgin Islands 335 Index 351 VI ILLUSTRATIONS Page Figure 1. Graph showing monthly-mean discharge of selected streams in Puerto Rico 4 2. Graph showing ground-water levels at selected wells in Puerto Rico and the U.S. Virgin Islands 6 3. Map showing location of maximum concentration of fecal coliform bacteria at sampled sites 10 4. Map showing location of maximum concentration of fecal streptococci bacteria at sampled sites 11 5. Map showing location of continuous surface-water and crest-stage gage stations in Puerto Rico 13 6. Map showing location of water-quality stations in Puerto Rico 14 7. Map showing location of ground-water stations in Puerto Rico 15 8. Map showing location of surface-water stations in the U.S. Virgin Islands 16 9. Map showing location of ground-water stations in the U.S. Virgin Islands 17 10. Grid showing system for numbering wells and miscellaneous sites (latitude and longitude) 18 11. Map showing Rio Guajataca basin 51 12. Map showing Rio Camuy basin 63 13. Map showing Rio Grande de Arecibo basin 69 14. Map showing Rio Grande de Manati basin 93 15. Map showing Rio Cibuco basin.... 111 16. Map showing Rio de la Plata basin 119 17. Map showing Rio Hondo to the Rio Puerto Nuevo basins 131 18. Map showing Rio Grande de Loiza basin 147 19. Map showing northeastern river basins--Rio Herrera to Rio Anton Ruiz basins.. 183 20. Map showing southeastern river basins--Rio Humacao to Rio Seco basins 204 21. Map showing south coast river basins--Rio Salinas to Rio Jacaguas basins.. 217 22. Map showing south coast river basins--Rio InabOn to Rio Loco basins 223 23. Map showing Rio Guanajibo basin 239 24. Map showing Rio Yagiiez and Rio Grande de Afiasco basins 255 25. Map showing Rio Culebrinas basin 265 VII TABLES Page Table 1. Island-wide monthly precipitation averages for 1987 water year and the 30-year reference period, 1951-80 3 2. Peak discharges during Apr. 11-13, 1987 and previous maximum at selected surface water gaging stations 5 3. Highest water level recorded during 1987 water year and previous extreme at selected ground-water wells in Puerto Rico and the U.S. Virgin Islands 7 4. Surface-water quality sites throughout Puerto Rico with the highest concentration of selected consituents during water year 1987 8 5. Factors for conversion of chemical constituents in milli- grams per liter to milliequivalents per liter 37 VIII SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED (Letter after station name designates type of data: (d) discharge, (c) water-quality, (e) elevation) Page RIO GUAJATACA BASIN Rio Guajataca at Lares (c) 52 Rio Guajataca above Lago Guajataca (d) 54 Canal Principal de Diversiones at Lago Guajataca (c) 56 Rio Guajataca below Lago Guajataca (d) 58 Rio Guajataca above mouth near Quebradillas (dc) 60 RIO CAMUY BASIN Rio Camuy near Bayaney (d) 64 Rio Camuy near Hatillo (d) 66 RIO GRANDE DE ARECIBO BASIN Rio Grande de Arecibo near Adjuntas (c) 70 Rio Grande de Arecibo near Utuado (c) 72 Rio Caonillas above Lago Caonillas near Jayuya (c) 74 Rio Grande de Arecibo below Lago Dos Bocas near Florida (c) 76 Rio Grande de Arecibo above Arecibo (d) 78 Rio Tanama near Utuado (dc) 80 Rio Tanama at Charco Hondo (d) 88 Rio Grande de Arecibo at Central Cambalache (c) 90 RIO GRANDE DE MANATI BASIN Rio Orocovis near Orocovis (c) 94 Rio Grande de Manati near Morovis (dc) 96 Rio Grande de Manati at Ciales (d) 99 Rio Grande de Manati at Highway 149 at Ciales (c) 101 Rio Cialitos at Highway 649 at Ciales (c) 103 Rio Grande de Manati at Highway 2 near Manati (dc) 105 LAGUNA TORTUGUERO BASIN Laguna Tortuguero Outlet near Vega Baja (c) 110 RIO CIBUCO BASIN Rio Cibuco below Corozal (dc) 112 Rio Cibuco at Vega Baja (dc) 115 RIO DE LA PLATA BASIN Rio de La Plata at Proyecto La Plata (dc) 120 Rio de La Plata near Comerio (c) 123 Rio Guadiana near Naranjito (c) 125 Rio de La Plata at Toa Alta (c) 127 Rio de La Plata at Highway 2 near Toa Alta (d) 130 RIO HONDO BASIN Rio Hondo at Flood Channel near Catafio (c) 132 ix SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED--Continued Page RIO DE BAYAMON BASIN Rio de Bayamon near Aguas Buenas (c) 134 Rio Guaynabo near Bayamon (c) 136 Rio de Bayamon at Flood Channel at Bayamon (c) 138 RIO PUERTO NUEVO BASIN Rio Piedras: Rio Piedras near Rio Piedras (c) 140 Laguna San Jose: Bahia de San Juan: Rio Piedras at Hato Rey (c) 142 Laguna San Jose No.2 at San Juan (c) 144 Bahia de San Juan No.5 at San Juan (c) 145 QUEBRADA BLASINA BASIN Quebrada Blasina near Carolina (c) 148 RIO GRANDE DE LOIZA BASIN Rio Grande de Loiza at Quebrada Arenas (d) 150 Rio Gurabo: Quebrada Blanca at El Jagual (d) 152 Quebrada Salvatierra near San Lorenzo (d) 154 Rio Cayaguas at Cerro Gordo (d) 156 Rio Turabo at Borinquen (d) 158 Rio Grande de Loiza at Caguas (dc) 160 Rio Caguitas at Highway 30 at Caguas (c) 163 Rio Bairoa near Caguas (c) 165 Quebrada Caimito near Juncos (d) 167 Rio Valenciano near Juncos (d) 169 Quebrada Mamey near Gurabo (d) 171 Rio Gurabo at Gurabo (d) 173 Rio Gurabo near Gurabo (c) 175 Lago Loiza at Damsite (c) 177 Rio Grande de Loiza below Damsite (d) 178 Rio Grande de Loiza below Trujillo Alto (c) 179 Rio CanOvanas near Campo Rico (d) 181 RIO ESPIRITU SANTO BASIN Quebrada Sonadora near El Verde (d) 184 Quebrada Toronja at El Verde (d) 186 Rio Espiritu Santo near Rio Grande (dc) 188 RIO MAMEYES BASIN Rio Mameyes near Sabana (d) 191 RIO SABANA BASIN Rio Sabana at Sabana (d) 193 X SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED--Continued RIO FAJARDO BASIN Rio Fajardo near Fajardo (dc) Rio Fajardo below Fajardo (c) Page 195 198 RIO BLANCO BASIN Rio Icacos near Naguabo (d) 200 RIO HUMACAO BASIN Rio Humacao at Highway 3 at Humacao (c) 204 RIO GUAYANES BASIN Rio Guayanes at Yabucoa (c) Rio Guayands above mouth at Playa de Guayanes (c) 206 208 RIO MAUNABO BASIN Rio Maunabo at Maunabo (c) 210 RIO CHICO BASIN Rio Chico at Providencia (c) 212 RIO GRANDE DE PATILLAS BASIN Rio Grande de Patillas near Patillas (dc) 214 RIO COAMO BASIN Rio Coamo near Coamo (c) 218 RIO DESCALABRADO BASIN Rio Descalabrado near Los Llanos (d) 220 RIO JACAGUAS BASIN Rio Jacaguas at Juana Diaz (d) 221 RIO INABON BASIN Rio Inabon at Real Abajo (d) 224 RIO BUCANA BASIN Rio Bucand: Rio Cerrillos near Ponce (c) 226 RIO PORTUGUES BASIN Rio Portugues near Ponce (dc) Rio Portugues at Ponce (c) 228 231 RIO GUAYANILLA BASIN Rio Guayanilla near Guayanilla (d) Rio Guayanilla at Central Rufina (c) 233 234 RIO LOCO BASIN Rio Loco at Guanica (c) 236 xi SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED—Continued Page LAGUNA JOYUDA BASIN Quebrada Mamey at Joyuda (d) 240 RIO GUANAJIBO BASIN Rio Guanajibo near San German (c) 241 Rio Rosario near Hormigueros (dc) 243 Rio Guanajibo near Hormigueros (dc) 252 RIO YAGUEZ BASIN Rio YagUez near Mayaguez (c) 256 RIO GRANDE DE ARASCO BASIN Rio Grande de Afiasco near Lares (c) 258 Rio Grande de Afiasco near San Sebastian (dc) 260 Rio Grande de Afiasco near Afiasco (c) 263 RIO CULEBRINAS BASIN Rio Culebrinas near San Sebastian (c) 266 Rio Culebrinas at Highway 404 near Moca (d) 268 Rio Culebrinas near Aguada (c) 270 ST. THOMAS, U.S. VIRGIN ISLANDS Bonne Resolution Gut at Bonne Resolution (d) 329 Turpentine Run at Mariendal (d) 330 ST. JOHN, U.S. VIRGIN ISLANDS Guinea Gut at Bethany (d) 331 ST. CROIX, U.S. VIRGIN ISLANDS Jolly Hill Gut at Jolly Hill (d) 332 XU GROUND-WATER WELLS, BY BASIN, FOR WHICH RECORDS ARE PUBLISHED Page RIO GUAJATACA BASIN Well 182422067015100 Local number 165 295 Well 182647066552400 Local number 202 296 RIO CAMUY BASIN Well 182856066510700 Local number 203 297 RIO GRANDE DE ARECIBO BASIN Well 182737066370900 Local number 204 298 RIO GRANDE DE MANATI BASIN Well 182621066343300 Local number 135.. 299 Well 182544066341500 Local number 205 300 Well 182757066325600 Local number 206 301 Well 182710066303700 Local number 207 302 Well 182534066283000 Local number 208 303 Well 182634066262500 Local number 209. 304 Well 182308066260400 Local number 210.. 305 RIO CIBUCO BASIN Well 182647066201700 Local number 70 306 Well 182615066235300 Local number 211 307 Well 182515066194000 Local number 212 308 Well 182330066185700 Local number 213 309 RIO DE LA PLATA BASIN Well 182746066170800 Local number 214 310 Well 182548066171200 Local number 215 311 Well 182530066135400 Local number 216 312 Well 182655066142400 Local number 217 313 RIO HONDO TO RIO PUERTO NUEVO BASINS Well 182623066111000 Local number 218 314 Well 182441066082600 Local number 219 315 Well 182413066044000 Local number 220 316 Well 182436066031200 Local number 221 317 RIO GRANDE DE LOIZA BASIN Well 182515065594100 Local number 222 318 RIO HUMACAO TO RIO SECO BASINS Well 175858066100200 Local number 6 319 RIO GUAYANES BASIN Well 180415065513900 Local number 96 320 GROUND-WATER WELLS, BY BASIN, FOR WHICH RECORDS ARE PUBLISHED Xiii Page RIO SALINAS TO RIO JACAGUAS BASINS Well 175829066232200 Local number 87 321 RIO INABON TO RIO LOCO BASINS Well 180133066503300 Local number 132 322 RIO GUANAJIBO BASIN Well 180132067033800 Local number 143 323 RIO CULEBRINAS BASIN Well 182018066593200 Local number 83 324 Well 182442067091700 Local number 200 325 ST. CROIX, U.S. VIRGIN ISLANDS Well 174225064471900 Local number 1 335 Well 174225064472000 Local number 2 336 Well 174243064475100 Local number 3 337 Well 174245064475800 Local number 4 338 Well 174308064484400 Local number 6 339 Well 174525064460600 Local number 7 340 Well 174527064460100 Local number 8 340 Well 174532064460300 Local number 9 341 Well 174329064454700 Local number 10 341 ST. THOMAS, U.S. VIRGIN ISLANDS Well 182050064580400 Local number 1 342 Well 182138064543100 Local number 2 342 Well 182138064542500 Local number 3 342 Well 182136064541900 Local number 4 343 Well 182029064535200 Local number 5 343 Well 182038064550300 Local number 6 344 ST. JOHN, U.S. VIRGIN ISLANDS Well 182010064472600 Local number 1 345 Well 182109064460300 Local number 2 345 Well 182116064451000 Local number 3 346 Well 182042064454500 Local number 5 347 Well 182044064454600 Local number 6 348 Well 182044064454800 Local number 7 348 Well 182044064454900 Local number 8 348 Well 182044064455000 Local number 9 349 Well 182044064455200 Local number 10 349 Well 181956064464500 Local number 11 350 XIV THIS PAGE WAS LEFT BLANK INTENTIONALLY 1 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 INTRODUCTION The Water Resources Division of the U.S. Geological Survey, in coopera­ tion with local and federal agencies obtains a large amount of data pertaining to the water resources of the Commonwealth of Puerto Rico and the Territory of the U.S. Virgin Islands each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the area. To make these data readily available to interested parties outside the Geological Survey, the data are published annually in this report series entitled "Water Resources Data for Puerto Rico and the U.S. Virgin Islands, 1987." This report includes records on both surface and ground water. Specifi­ cally, it contains: (1) Discharge records for 49 streamflow-gaging stations, and 1 crest-stage, partial-record streamflow station; (2) water-quality records for 16 streamflow-gaging stations, and for 42 ungaged streamsites, 11 lake sites, 1 lagoon, and 1 bay; and (3) water-level records for 56 observation wells. Water-resources data for Puerto Rico for calendar years 1958-67 were released in a series of reports entitled "Water Records of Puerto Rico". Water-resources data for the U.S. Virgin Islands for the calendar years 1962-69 were released in a report entitled "Water Records of U.S. Virgin Islands." Included were records of streamf low, ground-water levels, and water-quality data for both surface and ground water. Beginning with the 1968 calendar year, surface-water records for Puerto Rico were released separately on an annual basis. Ground-water level records and water-quality data for surface and ground water were released in companion reports covering periods of several years. Data for the 1973-74 reports were published under separate covers. Water-resources data reports for 1975-76, 1977, 1978, 1979-80, 1981-82, 1983, 1984, 1985, and 1986 water years consist of one volume each and contain data for streamflow, water quality and ground water. Publications similar to this report are published annually by the Geolog­ ical Survey for all States. These official Survey reports have an identifica­ tion number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PR-87-1". These water-data reports are for sale in paper copy or in microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, Virginia, 22161. Additional information, including current prices, for ordering specific reports may be obtained from the District Chief at the address given on back of title page or by telephone (809) 783-4660. 2 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 COOPERATION The U.S. Geological Survey has had cooperative agreements with organiza­ tions of the Commonwealth of Puerto Rico and the Territory of the U.S. Virgin Islands for the systematic collections of water resources data since 1958. Organizations that supplied data are acknowledged in the station descriptions. Organizations that assisted in collecting data through cooperative agreements with the Survey are: Puerto Rico Environmental Quality Board Puerto Rico Aqueduct and Sewer Authority Puerto Rico Department of Agriculture Puerto Rico Industrial Development Company Puerto Rico Department of Public Works Puerto Rico Highway Authority Puerto Rico Department of Natural Resources Puerto Rico Department of Health Puerto Rico Electric and Power Authority Puerto Rico Rice Corporation Puerto Rico Administration for Agricultural Development Puerto Rico Land Administration Center for Energy and Environment Research, University of Puerto Rico Water Resources Research Institute, University of Puerto Rico Water Resources Research Institute, College of the Virgin Islands Department of Public Works of the U.S. Virgin Islands Funds were also provided by the Corps of Engineers, U.S. Army, for the collection of records at five gaging stations published in this report. Ground-water quality data at selected sites was collected with support from the U.S. Environmental Protection Agency. SUMMARY OF HYDROLOGIC CONDITIONS Precipitation Precipitation was slightly higher than usual in the 1987 water year. Precipitation averaged about 104 percent of normal, islandwide, but varied from 121 percent of normal in the northern part of the island to 94 percent of normal in the western part of the island. Monthly average precipitation islandwide for water year 1987 and the 30-year (1951-80) normal as reported by the National Oceanic and Atmospheric Administration are listed in table 1. 3 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Table 1. Islandwide monthly precipitation and annual averages for 1987 water year and the 30-year reference period, 1951-80. 30-year Water year 1987 normal Month (inches) (inches) Oct. 7.12 7.74 Nov. 8.29 5.95 Dec. 2.95 4.32 Jan. 2.99 3.08 Feb. 3.86 2.35 Mar. 3.99 2.63 Apr. 5.83 4.63 May 9.61 6.48 June 8.78 5.58 July 3.59 5.48 Aug. 3.88 7.28 Sept. 5.18 7.78 TOTAL 66.07 63.30 Surface Water Streamflow in Puerto Rico was generally within normal range during water year 1987. A comparison of 1987 streamflows at 4 representative gaging stations to their long-term median and extreme monthly flows is shown in figure 1. Flows during October were below normal islandwide. The October mean flow for the Rio Grande de Manati gaging station, which is in the northern part of the island, was only 32 percent of the median flow. During November through January, Rio Grande de Manati flows remained below normal while flows at the other index stations, shown on figure 1, were very near their long-term median flows. February flows were near normal islandwide. During March streamflow continued to decrease seasonally in the northern, southern, and western parts of the island, but intense precipitation caused increased streamflow in the eastern part of the island. The index station on Rio Fajardo near Fajardo recorded a monthly mean discharge well above the long term median. Heavy rains caused significant flooding during April 11-13. The most notable flooding occurred in the northern and eastern parts of the island. Table 2 summarizes peaks experienced at 10 stations in the affected areas. Rio Cibuco at Vega Baja experienced the highest peak discharge since the station was established in 1973. Li 4 M ONTHLY MEAN DISCHARGE, I N CUBI C FEET PER SECON D rs, WEST NORTH RIO GRANDE DE ANASCO NEAR SAN SEBASTIAN RIO GRANDE DE MANATI AT HWY 2 (50144000) (50038100) 4000 4000 1000 1000 100 20 400 100 SOUTH RIO INABON AT REAL ABAJO (50112500) M ONTHLY M EAN DISCHARGE. IN CUBICFEETPERSECOND 100 1987 MONTHLY MEAN 1961-86 MEDIAN MONTHLY 20 EAST RIO FAJARDO NEAR FAJARDO (50071000) 400 100 10 10 1:7 > 03 >- Z -J O W > Z 03 CC >- Z _1 U 1.1.1 0- 4:( 3 O Li (-) 0 < W 121- D 3 0 z a M 2 < 0 z CI L.- 2 4 2 1986 1987 19136 1987 Unshaded area indicates range between highest and lowest monthly mean discharges for the period of record Figure 1.--Monthly mean discharge of selected streams in Puerto Rico. 5 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Table 2. Peak discharges during April 11-13, 1987 and previous maximum at selected surface water gaging stations in Puerto Rico April 1987 peak Maximum of record Period Station Station (cubic feet (cubic feet Water of number name per second) per second) Year Record 50031200 Rio Grande de 6,680 48,000 1985 1-65 to 9-87 Manati near Morovis 50035000 Rio Grande de 25,200 125,000 1971 2-59 to 9-87 Manati at Ciales 50038320 Rio Cibuco 11,400 13,600 1979 5-69 to 9-87 below Corozal 50039500 Rio Cibuco 33,000 30,300 1982 1-73 to 9-87 at Vega Baja 50046900 Rio de la Plata 19,200 95,500 1960 1-60 to 9-87 at Highway 2 near Toa Alta 50061800 Rio Canovanas 2,000 15,000 1982 3-67 to 9-87 near Campo Rico 50063440 Quebrada Sonadora 645 2,160 1985 3-83 to 9-87 near El Verde 50063800 Rio Espiritu Santo 7,960 12,400 1984 8-66 to 9-87 near Rio Grande 50065500 Rio Mameyes 6,320 19,800 1973 8-67 to 12-73, near Sabana 6-83 to 9-87 50075000 Rio Icacos 893 2,860 1983 1953 to 1962, near Naguabo 10-79 to 9-87 Flows for April, May, and June were well above normal in the northern and eastern part of the island and near normal in the western and southern parts. July flows varied from above normal at the northern index station to below normal at the western station. In August and September, monthly flows were generally below normal. In the U.S. Virgin Islands, conditions were generally the same as in Puerto Rico. Monthly precipitation totals were well above the 30-year normal in November, May, and June with 155, 254, and 248 percent of normal respectively. Ground Water In general, ground-water levels in representative observation wells rose during the two relatively wet seasons (October to December and April to May) in response to above normal rainfall. Record high water levels were recorded at several wells in Puerto Rico and the U.S. Virgin Islands in the 1987 water year (Table 3). 6 WATER LEVEL, INFEETBELOW LAND-SURFACE DATUM 20 25 30 35 WELL 70, SABANA HOYOS OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1986 1987 15 20 WELL 87, ALOMAR 1 25 30 35 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1986 1987 10 20 WELL 11, GUINEA GUT ST. JOHN, U.S.V.I. 30 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1986 1987 Figure 2 .--Ground—water levels at selected wells in Puerto Rico and the U.S. Virgin Islands. 7 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Ground-water levels in the north coast limestone aquifers of Puerto Rico remained practically unchanged during the first half of the water year (fig. 2). However, above normal precipitation during mid-April caused a significant rise in the water levels in this aquifer. At the Sabana Hoyos index well, an increase of 4.0 ft. was recorded. The water level in this well declined during the rest of the year except for a small rise in late May caused by heavy rainfall. At the end of water year 1987, the water level in this well was 1.40 ft. higher than that at the end of water year 1986. Ground-water levels in the alluvial aquifers along the south coast of Puerto Rico followed a cyclic pattern associated with streamflow and ground­ water withdrawals for public supply and irrigation uses. Generally, water levels declined throughout the period in response to low-streamflow conditions and increased ground-water withdrawals as shown in the hydrograph for well 87 in fig. 2. Table 3.--Highest water level recorded during 1987 water year and previous extreme at selected ground-water wells in Puerto Rico and the U.S. Virgin Islands (water levels in feet below land-surface datum) Well Local Location 1987 Date Previous Date Period of Name no. extreme extreme Record Saltos /1 1 165 PR 47.62 09-30-87 53.39 09-23-86 1-82 to 9-87 Coto Norte # 3 209 PR 68.40 04-15-87 71.50 07-23-86 10-85 to 9-87 Acropolis Manati 208 PR 225.95 05-31-87 228.21 05-18-86 1-86 to 9-87 Ponderosa TW-1 212 PR 63.05 07-15-87 64.00 12-01-85 10-85 to 9-87 Maguayo No. 5 215 PR 40.16 04-18-87 40.89 11-20-85 10-85 to 9-87 Pozo Navy 216 PR 9.38 06-23-87 10.17 11-21-85 10-85 to 9-87 Levittown No. 7 218 PR 6.13 02-22-87 6.52 10-09-85 10-85 to 9-87 Hyde Park TW-10 221 PR 1.48 04-12-87 1.92 05-14-86 12-85 to 9-87 Concordia II 14 7 St. Croix 12.54 06-17-87 15.56 11-13-84 03-82 to 9-87 8 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Ground water levels in the U.S. Virgin Islands (St. Thomas, St. Croix, and St. John) responded to the same climatological conditions that affected Puerto Rico. The water level rose 8.40 ft. in November and 9.10 ft. during June (fig. 2). At nearby recording wells, a maximum increase of 14.0 ft. was registered during both periods. By the end of water year 1987, the water level was 9.0 ft. lower than at the end of previous water year. Water Quality In the 1987 water year, the U.S. Geological Survey in cooperation with local government agencies, completed the third year of sampling for the constituents listed in table 4. These constituents were added to the water quality monitoring program in 1985 and are in addition to the major chemical constituents and physical properties monitored in the continuing water-quality monitoring program in Puerto Rico. The highest concentrations of selected constituents detected during the 1987 water year along with the stations at which these concentrations were detected are summarized in table 4. Table 4. Surface-water quality stations throughout Puerto Rico with highest concentration of selected constituents during water year 1987 (constituents concentrations in milligrams per liter) Station number Station name Constituent Concentration Sulfide 50047530 Rio Hondo at Flood Channel near Catafio Boron 1.7 50055250 Rio Caguitas at Hwy 30 at Caguas Copper 219 50083500 Rio Guayanes at Yabucoa Iron 46 50083500 Rio Guayanes at Yabucoa Manganese 1.5 50020500 Rio Grande de Arecibo near Adjuntas Zinc .31 50055250 Rio Caguitas at Hwy 30 at Caguas Cyanide .22 50043000 Rio de la Plata at Proyecto la Plata Phenols .03 50091800 Rio Chico at Providencia MBAS** 1.6 Explanation: * Sulfide concentration at all water-quality stations were below the detection limit (<0.5 mg/L). ** Methylene blue active substances. 9 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 The presence of high concentrations of fecal coliform (FC) and fecal streptococci (FS) bacteria continues being the principal surface water quality problem in Puerto Rico. Bacteria concentrations exceeding one million colonies per hundred milliliters of raw water were found at several stations including Rio Guadiana near Naranjito (50044850), Rio Hondo at the Flood Channel near Catailo (50047530), Rio Piedras near Rio Piedras (50048800), San Juan Bay No.5 at San Juan (50049920), Quebrada Blasina near Carolina (50050300), Rio Caguitas at Highway 30 at Caguas (50055250), Rio Bairoa near Caguas (50055400), and Rio Chico at Providencia (50091800). These sites are located near urban zones, industrial parks, and suburban zones and receive the effluent of the sewage treatment plants. Two sediment stations were operated during the year, one at the Rio Tanana near Utuado (50028000), and other at the Rio Rosario near Hormigueros (50136400). Maximum sediment concentrations recorded were 1,760 milligrams per liter (mg/L) at the Rio Tanama site, and 1,640 mg/L at the Rio Hormigueros site. Maximum sediment loads at these sites were 5,930 tons per day and 4,700 tons per day, respectively. 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 areal 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 THE RECORDS The surface-water and ground-water records published in this report are for the 1987 water year that began October 1, 1986 and ended September 30, 1987. 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 9. 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. 67°15' 67°00' 45' 30' 15' 6600' 45' 65°30' 1 ATL ANT IC OCEAN • otb "o(' oki, p 4A 3 botte d 6 tt =a i o 0 1 4e to 44 t 4 6 • , dal A 18°30 1/400° o r W 40 141)51 t` Rio Culebrinas i‘o Reci Guayabo Ria Grande Rio Fajardo Rio Grand. 15' de Afiasco Rio YagueZ Rio Daguao Ouebrada PRIMO Rio Santiago Rib Bianco \Rio Anton Ruiz Rio Humacao Rib Guanallbo o Guayanes \ ° 046 < , A A ..., dP A V' oc' Ye' ik V+4.04,ColV vo 4y, 0 „co \ 0 C„, \- 01,00o eo , 4 coko 0'4.1,01S0 ko 64oe 0 *60 41,;so sp FECAL COLIFORMS q,co ,_ 4 '4 t• 4, 0 a <1000 so 1 0 20 30 KILOMETERS MI 1000 - 10,000 E 17°451 L • 10,000 - 100,000 10 20 30 MILES • 100,000 - 1,000,000 CARIBBEAN SEA 111 > 1,000,000 1 1 Figure 3.--Location of maximum concentration of fecal coliform bacteria at sampled sites. 67°151 87°00' 45' 30' 15' woo' 45' 85°30' 1— A T L N T I C OCEAN • .t sk. ce* •0 00 .., 04 0 sk.. \i• 0A b .0 as 4. AstG 4 e tt 42' st 4 1, bole it,s 6. 0 (se C4/ 01 Co'Sf • 5* to 0 to ,2,0 I. to e te ,tek ' p 18°30 0 4 0 ie. 6 + b• 0i k0 e , -. ... .9 . t 7 +. V ii to , 0 „I% I.% oso +, 20 Rib Culebrinas ' co 4v I. _to Rib Guayabo icv la Grande Rio Fajardo Rob Grand* de Afiasco Rio Yaguaz Rio Daguao Rib Guanajibo cdusbrada Palma \ Rib Santiago Rio Blanco Rio Anton Ruiz fo Humacao Rio Guayana:* 18* 00' 6 ' V ,* ‘\\ o „ it , ,.0 i‘ _it. ., ,i, 47, , _ 64.01tp , . A q, • ANI. % .% '0 At 0‘' st‘ 0 vtU .1,1‘ e , e OV et%),‘ . tO e . 40 4% do ° + 41i%S 0'. i ° * Cr LOGO 4° 04 rCi 0 ‘0 . 0 to A.A.A ‘t.* ifr,et* tO 0C'ai* SO' .0 ,0 Cf ko .c.' ittYR0 V V, it- . 0 AO - So s Q. 0 FECAL STREPTOCOCCI iks ik 1 4 '4) : :. co o _1/0 4 e A 4? 0 /0 44 vo 4 •k v 00 ck I. e i1/4 l' + as N. .0 i.- - 0 ‘, • < 1000 ko .i., o 10 20 30 KILOMETERS • 1000 - 10,000 1 r4! • 10,000 - 100,000 10 20 30 MILES • 100,000 - 1,000,000 CARIBBEAN SEA > 1,000,000 Figure 4.--Location of maximum concentration of fecal streptococci bacteria at sampled sites. 12 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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 down­ stream 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 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. 10). °00' 45' 66°00' 45' 65°30' 1 T L A T C OCEA • b(` vol(1. st, $fi 3 \4 t 3 d0i,,i'' oe' 0 CI 1,.S t..3 S1 ,,,i. . , ,frb 0 ,0 e i,,.... b 9, „6. jet t, 0 _ 04 (Z• 18°30' ; 0 1/° 4 , 0 ,kki I.. 0114 li1O157 t,,0 ko co 0 e. qa 038 40395 Rib Culebrinas W0112 j R* f o c2 -027750 Rib Guayabo 0284& 7A- Grande 0638 59060 nanA A £0670 061 8idt £0 655 Rib Fajardo 0 3440111 07 0 Rib Grande A0570 _ Aolso- 15' de Ai!Bac° A05565 /A6564 Rio Vague 869 Rib Daguao Rib Guanajlbo \ Quebrada Palma 053050A 051310 Rio 05118 vo , '10509 Rib Anton Ruiz /05'1150 — Rio Humacao ^092q Rio Guayanis 18°00' • 0 04, S0 \ 30040 to 0 4 cpvt, e ,4.Ae vv $ \ ck Ao 0 • 0 .0 t AsV 1, 4 EXPLANATION 10 .11/4 ik‘ 0 0 oe'i1/4 n 0c1 1/4° .4" tik• 1.,‘• 0 SURFACE WATER STATIONS 9,‘ 20 q.` 1125 CONTINUOUS STREAMFLOW R.‘ ik R4 30 KILOMETERS 17°4 , • STATION ib 20 30 MILES 10490 CREST-STAGE GAGE CAR BBEAN SE A Figure 5.--Location of continuous surface-water and crest-stage gage stations in Puerto Rico. CO .t& 67°15' 67°00' 45' 30' 15' 66000' 45' 85°3 Rio Culebrines Rib Gueyabo ict Grande - 1491 ii*S to 0114 110 10790 ATLANT ,90 be C ty• 6 0 0 1/40 o ,6 6 90 038 0381 1 0 C OCEAN 1:1, , (k it. 0 \t. 0 0 4 0 g 440 Sets be e, 6°I,e +06 e 3 0 , 0 c% / to ki fi* co Co ae. , sio ik 0, 41. e• 1 /40 ,0, ov illirido,.. 47530 'i • 1114e, R's 4i. . *V 404982 co 4, is. *a S.% 010720 _76 ()16 0/280 15 Rib Grande do Astasco Rio Yaguez Rib Guanailbo Rio Daguao Quabrada Palma Rio Santiago Rib Blanco Rib Anton Ruiz Rio Humacao Rio Guayanois 18'00' oh .tik o. 0 e 4 , . • t "6 0 Ao 0- Aso0 0 6 .9 _to ti .i‘ 0 44 C7 i i0 00 ‘0 0 i Li Afte ‘. V 0 0 WO 0 Ito + p $ Np, ,y, ,- 4,1> , t J iv- o co • o se v-„1/40 ,0 'o 0 G ko •• R., 90 $ ‘ I. 0, 0 00 0 EXPLANATION R` R"‘1/40 I1/4 1/40 .0 P C°1/40 es co RS 1/40 (' w,0%' 1,:c) R. CI, 1.• “1/4 I. 9 t sik i0 0%i QUALITY-OF-WATER STATIONS ICo I` 're - 10 20 30 KILOMETERS y 0430 BIOLOGICAL 17°45' fk,:‘ 10 20 30 MILES 0820 CHEMICAL CARIBBEAN SEA —11, 0710 SEDIMENT (DAILY) inn 0 SEDIMENT (BI-MONTHLY) Figure 6.--Location of water-quality stations in Puerto Rico. 67°15' 87°00' 45' 30' 15 45' 65°30' -71 , ATLANTIC Of, E AN ,0 0 N. fai N.. 0 0 6411 \ %0 ee ,4c, 4e ,*1 e 0 0. o i os 0 4 ,0 ,o e 1 it0 izt,4 18°3 V 're ee q*..% : * 6205 21\4 -t''.1. 151 , 04. 135 •70 • 2 7 •1,- le , 3 4 01 Rio Culebrinas :0446 .2°7209 ' • . 218 Rth Guayabo oo 2013I" 1121i 212 , 216 2 44 222. q• l',;$ . '- 7'7220 .221 -0 Grande - , 210 1 213 1 ,...) , , Grand. de Aifasco Rfo Yaguez RA) Daguao RIO Guanajibo Ousbrada Palma , Rio Santiago Rfo Bianco Rso Anton Ruiz fo Humacao Guayanis 18°00' c.,0 .00 416040.30,44 c, 0v 0 e 11 zi% N1/4 ' 3' ° 1/40 •• 1/4° csc fi,‘) ° 1/° 4 ' 0 lk% 1/40 t0 ck 1, 1/400 0, *, 1 ° 1,1 it? tr 10 20 30 KILOMETERS EXPLANATION 10 20 30 MILES • 6 WELL AND WELL NUMBER SEA SE Figure 7.--Location of ground-water stations in Puerto Rico. UI 16 5°O5' 55 ST. THOMAS 18°24 18°20' 0 1 2 3 4 KILOMETERS I I 3 4 MILES 180 22' 18°18 ST. CROIX 64`)35° 17°45' 17°40' Fred 0 1 2 3 4 KILOMETERS 1 I I i I 1 2 3 4 MILES Figure 8.--Location of surface-water stations in the U.S. Virgin Islands. 17 18°24' 18c20° 0 1 2 3 4 KILOMETERS 1 O 1 2 3 4 MILES 1 84°50' 45° 1 64°4 16°22' ST. JOHN 180 18° 0 1 2 I I 0 1 4 KILOMETERS 1 3 4 MILES ST. CROIX 4 40° 4°3 1704, 744 Chris lansted Fred skated 17°4 0 1 2 3 4 KILOMETERS I 0 1 2 3 4 MILES Figure 9.--Location of ground-water stations in the U.S. Virgin Islands. 18 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 66°53' 52' 5" 50' 49' 48' 66°47' 18°02 COORDINATES FOR WELLS 27 (180150086474900) 134 .27 .74 ., AND 74 (180135088471000) 132e/ Ae - 0I' 1314 N COORDINATES FOR WELLS 132 (180133068503300) AND 134 (180120066503200) 18°00' COORDINATES FOR WELL 131 (180058068502700) 16 41 - ,de COORDINATES FOR WELL 16 (178922088495800) 17°59' Figure 10.--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. 19 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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 slected 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. 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 approx­ imate discharge for any stage within the range of the measurements are pre­ pared. If it is necessary to define extremes of discharge outside the range of the current-meter measurements, the curves are extended using: (1) loga­ rithmic plotting; (2) velocity-area studies; (3) results of indirect measure­ ments of peak discharge, such as slope-area or contracted-opening measure­ ments, 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 dis­ charge 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. 20 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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 follow­ ing 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 informa­ tion, such as station location; period of record; average discharge; histori­ cal extremes; record accuracy; and other remarks pertinent to station opera­ tion 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 pub­ lished 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. REVISED RECORDS.--Published records, because of new information, occa­ sionally 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. 21 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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.--All 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 sec­ tion, "Identifying Estimated Daily Discharge.") If a remarks statement is used to identify estimated record, the paragraph will begin with this informa­ tion 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 spill­ way, 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 other­ wise qualified, and was determined and is reported in the same manner as the maximum. EXTREMES OUTSIDE PERIOD OF RECORD.--Included here is information concern­ ing 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. 22 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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 dis­ charges 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. 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. 23 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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 stabil­ ity 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 less than 1 ft3/s; to the nearest tenth between 1.0 and 10 ft3/s; 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 measure­ ments, 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. 24 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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 collec­ ted 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 areal 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 conduct­ ance, 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 sepa­ rate 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, care­ fully 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. 25 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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 repre­ sentative 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 analy­ sis. In the rare case where an apparent inconsistency exists between a reported pH value and the relative abundance of carbon dioxide species (carbon­ ate 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. 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 tempera­ tures 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. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Sediment Suspended-sediment concentrations are determined from samples collected by using depth-integrating 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 concentra­ tion, 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 pub­ lished 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 concentra­ tions 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 stream- flow 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 ana­ lyzed 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. 27 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 In the descriptive headings, if the location is identical to that of the discharge gaging station, neither the LOCATION nor the DRAINAGE AREA state­ ments 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. 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 pub­ lished water-quality records for the station. The periods are shown separate­ ly 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 subse­ quently 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 miscel­ laneous 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. 28 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Remark Codes The following remark codes may appear with the water-quality data in this report: PRINTED OUTPUT REMARK Estimated value Actual value is known to be greater than the value shown Actual value is known to be less than the value shown Results based on colony count outside the acceptance range (non-ideal colony count) Biological organism count less than 0.5 percent (organism may be observed rather than counted) Biological organism count equal to or greater than 15 percent (dominant) Biological organism estimated as dominant 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 observa­ tion 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. 29 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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 (lsd). Land-surface datum is a datum plane that is approxi­ mately 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 descrip­ tion. 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 determina­ tion. 30 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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. Geologi­ cal 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. EXTREMES FOR PERIOD OF RECORD.--This entry contains the highest and low­ est 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 instanteous 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. 31 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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 analy­ sis. 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 National WATer Data STOrage and REtrieval System (WATSTORE) was established for handling water data collected through the activities of the U.S. Geological Survey and to provide for more effective and efficient means of releasing the data to the public. The system is operated and maintained on the central computer facilities of the Survey at its National Center in Reston, Virginia. WATSTORE can provide a variety of useful products ranging from simple data tables to complex statistical analyses. A minimal fee, plus the actual computer cost incurred in producing a desired product, is charged to the requester. Information about the availability of specific types of data, the acquisition of data or products, and user charges can be obtained locally from each of the Water Resources Division's District offices (see address given on the back of the title page). General inquiries about WATSTORE may be directed to: Chief Hydrologist U.S. Geological Survey 437 National Center Reston, Virginia 22092 32 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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. 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 (nutri­ ent medium for bacterial growth). Their concentrations are expressed as number of colonies per 100 mL of sample. 33 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Fecal coliform bacteria are bacteria that are present in the intestines or feces of warm-blooded animals. They are often used as in­ dicators 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 colo­ nies 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 lab­ oratory 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 ex- pressed 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, ex­ pressed 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 periphy­ ton 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 differ­ ence 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 living 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). 34 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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. 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 constric­ tion 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. 35 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Dissolved refers to that material in a representative water sample which passes through a 0.45 um 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: n. n. 1 d = - E --- log — n 2 71 i=1 Where ni 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. 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. 38 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 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 hydrol­ ogy, including water quality, and related factors in representative un­ developed 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 (lsd) 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 differ­ ence 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 concentra­ tion 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. 37 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Table 5. Factors for conversion of chemical constituents in milligrams per liter to milliequivalents per liter. Ion Multiply by Ion Multiply by Aluminum (A1+3)* 0.11119 Iodide (I-1) 0.00788 Ammonia as NH4+1 05544 Iron (Fe+3) .05372 Barium (Ba+2) 01456 Lead (Pb+2) .00965 Bicarbonate (HCO3-1). . . .01639 Lithium (Li+1) .14411 Bromide (Br-1) .01251 Magnesium (Mg+2).. .08226 Calcium (Ca+2) .04990 Manganese (Mn+2)* .03640 Carbonate (CO3-2) 03333 Nickel (Ni+2) .03406 Chloride (C1-1) 02821 Nitrate (NO3-1) .01613 Chromium (Cr+6)* 11539 Nitrite (NO2-1) .02174 Cobalt (Co+2)* .03394 Phosphate (PO4-3)... .03159 Copper (Cu+2)* 03148 Potassium (K+1) .02557 Cyanide (CN-1) 03844 Sodium (NA+1) .04350 Fluoride (F-1) .05264 Strontium (Sr+2).. .. .02283 Hydrogen (H+1) 99209 Sulfate (SO4-2) .02082 Hydroxide (OH-1) 05880 Zinc (Zn+2)* .03060 *Constituent reported in micrograms per liter; multiply by factor and divide results by 1,000. 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 in 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 areal variability of water quality in the Nation's rivers through analysis of description of the areal 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. 38 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 National Trends Network (NTN) is a network for sampling atmospheric deposition in the United States. The purpose of the network is to determine the variability, both in location and in time, of the composition of atmos­ pheric deposition, which includes snow, rain, dust particles, aerosols, and gases. The core from which the NTN was built was the already-existing deposi­ tion-monitoring network of the National Atmospheric Deposition Program (NADP). Organism is any living entity. Organism count/area refers to the number of organisms collected and enumerated in a sample and adjusted to the number per unit area habitat, usually square meters (m2), acres, or hectare. Periphyton, benthic organisms, and macrophytes are expressed in these terms. Organism count/volume refers to the number of organisms collected and enumerated in a sample and adjusted to the number per sample volume, usually milliliters (mL) or liters (L). Numbers of planktonic organisms can be expressed in these terms. Total organism count is the total number of organisms collected and enumerated in any particular sample. Parameter Code is a 5-digit number used in the U.S. Geological Survey computerized data system, WATSTORE, to uniquely identify a specific constitu­ ent. The codes used in WATSTORE are the same as those used in the U.S. Environmental Protection Agency data system, STORET. The Environmental Protection Agency assigns and approves all requests for new codes. Partial-record station is a particular site where limited streamf low and/or water-quality data are collected systematically over a period of years for use in hydrologic analyses. Particle-size is the diameter, in millimeters (mm), of a particle deter­ mined by either sieve or sedimentation methods. Sedimentation methods (pipet, bottom-withdrawal tube, visual-accumulation tube) determine fall diameter of particles in either distilled water (chemically dispersed) or in native water (the river water at the time and point of sampling). Particle-size classification used in this report agrees with recommenda­ tions made by the American Geophysical Union Subcommittee on Sediment Termi­ nology. The classification is as follows: Classification Size (mm) Method of analysis Clay 0.00024 - 0.004 Sedimentation Silt .004 - .062 Sedimentation Sand .062 - 2.0 Sedimentation or sieve Gravel 2.0 - 64.0 Sieve The particle-size distributions given in this report are not necessarily representative of all particles in transport in the stream. Most of the organic matter is removed and the sample is subjected to mechanical and chemical dispersion before analysis in distilled water. Chemical dispersion is not used for native water analysis. 39 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Percent composition is a unit for expressing the ratio of a particular part of a sample or population to the total sample or population, in terms of types, numbers, mass or volume. Periphyton is the assemblage of microorganisms attached to and living upon submerged solid surfaces. While primarily consisting of algae, they also include bacteria, fungi, protozoa, rotifers, and other small organisms. Pesticides are chemical compounds used to control undesirable organisms. Major categories of pesticides include insecticides, miticides, fungicides, herbicides, and rodenticides. -12 Picocurie (PC, pCi) is one trillionth (1 X 10 ) of the amount of ratioactivity represented by a curie (Ci). A curie is the amount of radio­ activity that yields 3.7 x 1010 radioactive disintegrations per second. A picocurie yields 2.22 dpm (disintegrations per minute). Plankton is the community of suspended, floating, or weakly swimming organisms that live in the open water of lakes and rivers. Phytoplankton is the plant part of the plankton. They are usually microscopic and their movement is subject to the water currents. Phyto­ plankton growth is dependent upon solar radiation and nutrient substan­ ces. Because they are able to incorporate as well as release materials to the surrounding water, the phytoplankton have a profound effect upon the quality of the water. They are the primary food producers in the aquatic environment, and are commonly known as algae. Blue-green algae are a group of phytoplankton organisms having a blue pigment, in addition to the green pigment called chlorophyll. Blue-green algae often cause nuisance conditions in water. Diatoms are the unicellular or colonial algae having a sili­ ceous shell. Their concentrations are expressed as number of cells per milliliter (cells/mL) of sample. Green algae have chlorophyll pigments similar in color to those of higher green plants. Some forms produce algae mats or floating "moss" in lakes. Their concentrations are expressed as number of cells per milliliter (cells/mL) of sample. Zooplankton is the animal part of the plankton. Zooplankton are ca­ pable of extensive movements within the water column and are often large enough to be seen with the unaided eye. Zooplankton are secondary consu­ mers feeding upon bacteria, phytoplankton, and detritus. Because they are the grazers in the aquatic environment, the zooplankton are a vital part of the aquatic food web. The zooplankton community is dominated by small crustaceans and rotifers. 40 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Primary productivity is a measure of the rate at which new organic matter is formed and accumulated through photosynthetic and chemosynthe­ tic activity of producer organisms (chiefly, green plants). The rate of primary production is estimated by measuring the amount of oxygen released (oxygen method) or the amount of carbon assimilated by the plants (carbon method). Mil11grams of carbon per area or volume per unit time [mK 2 C/(m .time] for periphyton and macrophytes and [mg C/(m .time)] for phytoplankton are units for expressing primary productivity. They define the amount of carbon dioxide consumed as measured by radio- active carbon (carbon 14). The carbon 14 method is of greater sensitivity than the oxygen light and dark bottle method, and is preferred for use in unenriched waters. Unit time may be either hour or day, depending on the incubation period. Milligrams of oxygen per area or volume per unit Sime [mg0 / 2 (m .time)] for periphyton and macrophytes and [mg0 /(m .time)] for phytoplankton are the units for expressing primary productivity. They define production and respiration rates as estimated from changes in the measured dissolved-oxygen concentration. The oxygen light and dark bottle method is preferred if the rate of primary production is sufficient for accurate measurements to be made within 24 hours. Unit time may be either the hour or day, depending on the incubation period. Polychlorinated biphenyls (PCBs) are industrial chemicals that are mix­ tures of chlorinated biphenyl compounds having various percentages of chlo­ rine. They are similar in structure to organochlorine insecticides. Radiochemical program is a network of regularly sampled water-quality stations where samples are collected to be analyzed for radioisotypes. The streams that are sampled represent major drainage basins in the conterminous United States. Recoverable from bottom material is the amount of a given constituent that is in solution after a representative sample of bottom material has been digested by a method (usually using an acid or mixture of acids) that results in dissolution of readily soluble substances. Complete dissolution of all bottom material is not achieved by the digestion treatment and thus the determination represents less than the total amount (that is, less than 95 percent) of the constituent in the sample. To achieve comparability of analytical data, equivalent digestion procedures would be required of all laboratories performing such analyses because different digestion procedures are likely to produce different analytical results. Return period is the average time interval between occurrences of a hydrological event of a given or greater magnitude, usually expressed in years. May also be called recurrence interval. Runoff in inches (IN, in) shows the depth to which the drainage area would be covered if all the runoff for a given time period were uniformly distributed on it. 41 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Sediment is solid material that originates mostly from disintegrated rocks and is transported by, suspended in, or deposited from water; it in­ cludes chemical and biochemical precipitates and decomposed organic material, such as humus. The quantity, characteristics, and cause of the occurrence of sediment in streams are influenced by environmental factors. Some major factors are degree of slope, length of slope, soil characteristics, land usage, and quantity and intensity of precipitation. Bed load is the sediment that is transported in a stream by rolling, sliding, or skipping along the bed and very close to it. In this report, bed load is considered to consist of particles in transit within 0.25 ft of the streambed. Bed load discharge (tons per day) is the quantity of bed load measured by dry weight that moves past a section as bed load in a given time. Suspended sediment is the sediment that at any given time is main­ tained in suspension by the upward components of turbulent currents or that exists in suspension as a colloid. Suspended-sediment concentration is the velocity-weighted concentra­ tion of suspended sediment in the sampled zone (from the water surface to a point approximately 0.3 ft above the bed) expressed as milligrams of dry sediment per liter of water-sediment mixture (mg/L). Mean concentration is the time-weighted concentration of suspended sediment passing a stream section during a 24-hour day. Suspended-sediment discharge (tons/day) is the rate at which dry mass of sediment passes a section of a stream or is the quantity of sediment, as measured by dry mass or volume, that passes a section in a given time. It is calculated in units of tons per day as follows: concentrations (mg/L) x discharge ft /s) x 0.0027. Suspended-sediment load is a general term that refers to material in suspension. It is not synonymous with either discharge or concentration. Total sediment discharge (tons/day) is the sum of the suspended- sediment discharge and the bed-load discharge. It is the total quantity of sediment, as measured by dry mass or volume, that passes a section during a given time. Total-sediment load or total load is a term which refers to the total sediment (bed load plus suspended-sediment load) that is in trans­ port. It is not synonymous with total-sediment discharge. 42 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Sodium-adsorption-ratio (SAR) is the expression of relative activity of sodium ions in exchange reactions within soil and is an index of sodium or alkali hazard to the soil. Waters range in respect to sodium hazard from those which can be used for irrigation on almost all soils to those which are generally unsatisfactory for irrigation. Solute is any substance that is dissolved in water. Specific conductance is a measure of the ability of a water to conduct an electric current. It is expressed in microsiemens per centimeter at 25°C. Specific conductance is related to the type and concentration of ions in solution and can be used for approximating the dissolved-solids content of the water. Commonly, the concentration of dissolved solids (in milligrams per liter) is about 65 percent of the specific conductance (in micromhos). This relation is not constant from stream to stream, and it may vary in the same source with changes in the composition of the water. Stage-discharge relation is the relation between gage height (stage) and volume of water per unit of time, flowing in a channel. Streamf low is the discharge that occurs in a natural channel. Although the term "discharge" can be applied to the flow of a canal, the word "streamflow" uniquely describes the discharge in a surface stream course. The term "streamflow" is more general than "runoff" as streamf low may be applied to discharge whether or not it is affected by diversion or regulation. Substrate is the physical surface upon which an organism lives. Natural substrate refers to any naturally occurring emersed or submersed solid surface, such as a rock or tree, upon which an organism lives. Artificial substrate is a device which is purposely placed in a stream or lake for colonization of organisms. The artificial substrate simplifies the community structure by standardizing the substrate from which each sample is taken. Examples of artificial substrates are basket samplers (made of wire cages filled with clean streamside rocks) and multiplate samplers (made of hardboard) for benthic organism collection, and plexiglass strips for periphyton. Surface area of a lake is that area outlined on the latest U.S.G.S. topographic map as the boundary of the lake and measured by a planimeter in acres. In localities not covered by topographic maps, the areas are computed from the best maps available at the time planimetered. All areas shown are those for the stage when the planimetered map was made. Surficial bed material is that part (0.1 to 0.2 ft) of the bed material that is sampled using U.S. Series Bed-Material Samplers. Suspended (as used in tables of chemical analyses) refers to the amount (concentration) of the total concentration in a water-sediment mixture. It is associated with the material retained on a 0.45-micrometer filter. 43 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Suspended, recoverable is the amount of a given constituent that is in solution after the part of a representative water-suspended sediment sample that is retained on a 0.45 um membrane filter has been digested by a method (usually using a dilute acid solution) that results in dissolution of only readily soluble substances. Complete dissolution of all the particulate matter is not achieved by the digestion treatment and thus the determination represents something less than the "total" amount (that is, less than 95 percent) of the constituent present in the sample. To achieve comparability of analytical data, equivalent digestion procedures are required of all laboratories performing such analyses because different digestion procedures are likely to produce different analytical results. Determinations of "suspended, recoverable" constituents are made either by analyzing portions of the material collected on the filter or, more commonly, by difference, based on determinations of (1) dissolved and (2) total recoverable concentrations of the constituent. Suspended, total is the total amount of a given constituent in the part of representative water-suspended sediment sample that is retained on a 0.45 um membrane filter. This term is used only when the analytical procedure assures measurement of at least 95 percent of the constituent determined. A knowledge of the expected form of the constituent in the sample, as well as the analytical methodology used, is required to determine when the results should be reported as "suspended, total." Determinations of "suspended, total" constituents are made either by analyzing portions of the material collected on the filter or, more commonly, by difference, based on determinations of (1) dissolved and (2) total concen­ trations of the constituent. Taxonomy is the division of biology concerned with the classification and naming of organisms. The classification of organisms is based upon a hierarchial scheme beginning with Kingdom and ending with Species at the base. The higher the classification level, the fewer features the organisms have in common. For example, the taxonomy of a particular mayfly, Hexagenia limbata, is the following: Kingdom Phylum Class Animal Arthopoda Insecta Order Family Genus Species Ephemeroptera Ephemeridae Hexagenia Hexagenia limbata Thermograph is an instrument that continuously records variations of temperature on a chart. The more general term "temperature recorder" is used in the table heading and refers to any instrument that records temperature whether on a chart, a tape, or any other medium. Time-weighted average is computed by multiplying the number of days in the sampling period by the concentrations of individual constituents for the corresponding period and dividing the sum of the products by the total number of days. A time-weighted average represents the composition of water that would be contained in a vessel or reservoir that had received equal quantities of water from the stream each day for the year. 44 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Tons per acre-foot indicates the dry mass of dissolved solids in 1 acre-foot of water. It is computed by multiplying the concentration of the constituent, in milligrams per liter by 0.00136. Tons per day (T/DAY) is the quantity of a substance in solution or suspension that passes a stream section during a 24-hour period. Total is the total amount of a given constituent in a representative water-suspended sediment sample, regardless of the constituent's physical or chemical form. This term is used only when the analytical procedure assures measurement of at least 95 percent of the constituent present in both the dissolved and suspended phases of the sample. A knowledge of the expected form of the constituent in the sample, as well as the analytical methodology used, is required to judge when the results should be reported as "total." (Note that the word "total" does double duty here, indicating both that the sample consists of a water-suspended sediment mixture and that the analytical method determined all of the constituent in the sample.) Total discharge is the total quantity of any individual constituent, as measured by dry mass or volume, that passes through a stream cross-section per unit of time. This term needs to be qualified, such as "total sediment discharge," "total chloride discharge," and so on. Total, recoverable is the amount of a given constituent that is in solution after a representative water-suspended sediment sample has been digested by a method (usually using a dilute acid solution) that results in dissolution of only readily soluble substances. Complete dissolution of all particulate matter is not achieved by the digestion treatment, and thus the determination represents something less than the "total" amount (that is, less than 95 percent) of the constituent present in the dissolved and suspended phases of the sample. To achieve comparability of analytical data, equivalent digestion procedures are required of all laboratories performing such analyses, because different digestion procedures are likely to produce different analytical results. Tritium Network is a network of stations which has been established to provide baseline information on the occurrence of tritium in the Nation's surface waters. In addition to the surface-water stations in the network, tritium data are also obtained at a number of precipitations stations. The purpose of the precipitation stations is to provide an estimate sufficient for hydrologic studies of the tritium input to the United States. Water year in Geological Survey reports dealing with surface water supply is the 12-month period, October 1 through September 30. The water year is designated by the calendar year in which it ends and which includes 9 of the 12 months. Thus, the year ending September 30, 1980, is called the "1980 water year." WDR is used as an abbreviation for "Water-Data Report" in the REVISED RECORDS paragraph to refer to State annual hydrologic-data reports (WED was used as an abbreviation for "Water-Resources Data" in reports published prior to 1976). 45 WATER RESOURCES FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1987 Weighted average is used in this report to indicate discharge-weighted average. It is computed by multiplying the discharge for a sampling period by the concentrations of individual constituents for the corresponding period and dividing the sum of the products by the sum of the discharges. A discharge- weighted average approximates the composition of water that would be found in a reservoir containing all the water passing a given location during the water year after thorough mixing in the reservoir. WSP is used as an abbreviation for "Water-Supply Paper" in references to previously published reports. 46 PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS The U.S. Geological Survey publishes a series of manuals describing procedures for planning and conducting specialized work in water-resources investigations. The material is grouped under major subject headings called books and is further divided into sections and chapters. For example, Section A of Book 3 (Applications of Hydraulics) pertains to surface water. The chapter, the unit of publication, is limited to a narrow field of subject matter. This format permits flexibility in revision and publication as the need arises. The reports listed below are for sale by the U.S. Geological Survey, Books and Open- File Reports Section, Federal Center, Box 25425, Denver, Colorado 80225 (authorized agent of the Superintendent of Documents, Government Printing Office). Prepayment is required. Remittance should be sent by check or money order payable to the U.S. Geological Survey. Prices are not included because they are subject to change. Current prices can be obtained by writing to the above address. When ordering or inquiring about prices for any of these publications, please give the title, book number, chapter number, and "U.S. Geological Survey Techniques of Water-Resources Investigations." 1-D1. Water temperature--influential factors, field measurement, and data presentation, by H. H. Stevens, Jr., J. F. Ficke, and G. F. Smoot: USGS--TWRI Book 1, Chapter Dl. 1975. 65 pages. 1-D2. Guidelines for collection and field analysis of ground-water samples for selected unstable constituents, by W. W. Wood: USGS--TWRI Book 1, Chapter 02. 1976. 24 pages. 2-D1. Application of surface geophysics to ground-water investigations, by A. A. R. Zohdy, G. P. Eaton, and D. R. Mabey: USGS--TWRI Book 2, Chapter Dl. 1974. 116 pages. 2-El. Application of borehole geophysics to water-resourcee investigations, by W. S. Keys and L. M. MacCary: USGS--TWRI Book 2, Chapter El. 1971. 126 pages. 3-Al. general field and office procedures for indirect discharge measurements, by M. A. Benson and Tate Dalrymple: USGS--TWRI Book 3, Chapter Al. 1967. 30 pages. 3-A2. Measurement of peak discharge by the slope-area method, by Tate Dalrymple and M. A. Benson: USGS--TWRI Book 3, Chapter A2. 1967. 12 pages. 3-A3. Measurement of peak discharge at culverts by indirect methods, by G. L. Bodhaine: USGS-­ TWRI Book 3, Chapter A3. 1968. 60 pages. 3-A4. Measurement of peak discharge at width contractions by indirect methods, by H. F. Matthai: USGS--TWRI Book 3, Chapter A4. 1967. 44 Pages. 3-A5. Measurement of peak discharge at dams by indirect methods, by Harry Hulsing: USGS--TWRI Book 3, Chapter AS. 1967. 29 pages. 3-A6. General procedure for gaging streams, by R. W. Carter and Jacob Davidian: USGS--TWRI Book 3, Chapter A6. 1968. 13 pages. 3-A7. Stage measurements at gaging stations, by T. J. Buchanan and W. P. Somers: USGS--TWRI Book 3, Chapter Al. 1968. 28 pages. 3-A8. Discharge measurements at gaging stations, by T. J. Buchanan and W. P. Somers: USGS--TWRI Book 3, Chapter A8. 1969. 65 pages. 3-A9. Measurement of time of travel and dispersion in streams by dye tracing, by E. F. Hubbard, F. A. Kilpatrick, L. A. Martens, and J. F. Wilson, Jr.: USGS--TWRI Book 3, Chapter A9. 1982. 44 pages. 3-A10. Discharge ratings at gaging stations, by E. J. Kennedy: USGS--TWRI Book 3, Chapter A1U. 1984. 59 pages. 3-All. Measurement of discharge by moving-boat method, by G. F. Smoot and C. E. Novak: USGS--TWRI Book 3, Chapter All. 1969. 22 pages. 3-A13. Computation of continuous records of streamfLow, by E. J. Kennedy: USGS--TWRI Book 3, Chapter A13. 1983. 53 pages. 3-A14. Use of flumes in measuring discharge, by F. A. Kilpatrick and V. R. Schneider: USGS--TWRI Book 3, Chapter A14. 1983. 46 pages. 3-A15. Computation of water-surface profiles in open channels, by Jacob Davidian: USGS--TWRI Book 3, Chapter A15. 1984. 48 pages. 3-B1. Aquifer-test design, observation, and data analysis, by R. W. Stallman: Chapter Bl. 1971. 26 pages. USGS--TWRI Book 3, 3-B2. Introduction to ground-water hydraulics, a programed text for self-instr Bennett: USGS--TWRI Book 3, Chapter B2. 1976. 172 pages. uction, by G. D. 3-B3. Type curves for selected problems of flow to wells in confined aquifers, USGS-TWRI Book 3, Chapter 83. 1980. 106 pages. by J. E. Reed: PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS-Continued 47 3-Cl. Fluvial sediment concepts by H. P. Guy: USGS--TWRI Book 3, Chapter Cl. 1970. 55 page 3-C2. Field methods for measurement of fluvial sediment TWRI Book 3, Chapter C2. 1970. 59 pages. by H. P. Guy and V. W. Norman: USGS-­ 3-C3. Computation of fluvial-sediment discharge Chapter C3. 1972. 66 pages. by George Porterfield: USGS--TWRI book 3, 4-Al. Some statistical tools in hydrology, by H. C. Riggs: 39 pages. USGS--TWRI Book 4, Chapter Al. 1968. 4-A2. Frequency curves, by H. C. Riggs: USGS--TWRI Book 4, Chapter A2. 1968. 15 pages. 4-61. Low-flow investigations, by H. C. Riggs: USGS--TWRI Book 4, Chapter 61. 1972. 18 pages. 4-82. Storage analyses for water supply, by H. C. Riggs and C. H. Hardison: Chapter 62. 1973. 20 pages. USGS--TWRI Book 4, 4-B3. Regional analyses of streamflow characteristics 63. 1973. 15 pages. by H. C. Riggs: USGS--TWRI Book 4, Chapter 4-01. Computation of rate and volume of stream depletion by wells Book '4, Chapter Dl. 1970. 17 pages. by C. T. Jenkins: USGS--TWRI 5-Al. Methods for determination of inorganic substances in water and fluvial sediments by M. W. Skougstad and others, editors: USGS--TWRI Book 5, Chapter Al. 1979. 626 pages. 5-A2. Determination of minor elements in water by emission spectroscopy. by P. R. Barnett ana E. C. Mallory, Jr.: USGS--TWRI Book 5, Chapter A2. 1971. 31 pages. 5-A3. Methods for analysis of organic substances in water. by D. F. Goerlitz and Eugene Brown: USGS--TWRI Book 5, Chapter A3. 1972. 40 pages. 5-A4. Methods for collection and analysis of aquatic biological and microbiological samples edited by P. E. Greeson, T. A. Ehlke, G. A. Irwin, B. W. Lium, and K. V. Slack: USGS--TWRI Book 5, Chapter A4, 1977. 332 pages. 5-A5. Methods for determination of radioactive substances in water and fluvial sediments by L. L. Thatcher, V. J. Janzer, and K. W. Edwards: USGS--TWRI Book 5, Chapter A5. 1977. 95 pages. 5-A6. Quality assurance practices for the chemical and biological analyses of water and fluvial sedments, by L. C. Friedman and D. E. Erdmann: USGS--TWRI Book 5, Chapter AS. 1982. 181 pages. 5-Cl. Laboratory theory and methods for sediment analysis Chapter Cl. 1969. 58 pages. by H. P. Guy: USGS--TWRI Book 5, 7-01. Finite difference model for aquifer simulation in two dimensions with results of numerical experiments, by P. C. Trescott, G. F. Pinder, and S. P. Larson: USGS--TWRI Book 7, Chapter Cl. 1976. 116 pages. 7-C2. Computer model of two-dimensional solute transport and dispersion in ground water, by L. F. Konikow and J. D. Bredehoeft: USGS--TWRI Book 7, Chapter C2. 1978. 90 pages. 7-C3. A model for simulation of flow in singular and interconnected channels by R. W. Schaffrannek, R. A. Baltzer, and D. E. Goldberg: USGS--TWRI Book 7, Chapter 13. 1981. 110 pages. 8-Al. Methods of measuring water levels in deep wells TWRI Book 8, Chapter Al. 1968. 23 pages by M. S. Garber and F. C. Koopman: USGS-­ 8-A2. Installation and service manual for U.S. Geological Survey manometers by J. D. Craig: USGS--TWRI Book 8, Chapter A2. 1983. 57 pages. 8-82. Calibration and maintenance of vertical-axis type current meters Novak: USGS--TWRI Book 8, Chapter B2. 1968. 15 pages. by G. F. Smoot and C. E. 48 THIS PAGE WAS LEFT BLANK INTENTIONALLY Surface and Quality-of-Water Records for Puerto Rico 50 THIS PAGE WAS LEFT BLANK INTENTIONALLY 51 ATLANTIC OCEAN • 0114 QUEBRADILLAS .202 de Diversidn AGUADILLA se 0166 /1 / -0112 0110 010790 Drainage boundaries iodieteresi.note in limestone terrone ealocfae, 010720 Limestone Igneous and t.b sedimentary rocks 0106 ...\\ \\ •"--, ....., \ *\ \ '-'-----,, -N, LARES 01 ftl'o Culebrinas. basin R.O Grande de Aio3C0 40,in EXPLANATION A0106 SURFACE—WATER STATION AND NUMBER V 0105 QUALITY—OF—WATER STATION AND NUMBER ,V0720 QUALITY—OF—WATER PARTIAL RECORD STATION AND NUMBER • 165 WELL AND WELL NUMBER op area IMMO tiAYAGU 2 4 5 KILOMETERS 1 3 4 SMILES Figure 11.--Rio Guajataca basin. 52 RIO GUAJATACA BASIN 50010500 RIO GUAJATACA AT LARES, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°1801, long 66° 5224, at bridge on Highway 111 (km 32.9), 0.1 ml (0.2 km) upstream from Quebrada Anon, and 0.4 ml (0.6 km) northeast of Lares plaza. DRAINAGE AREA.--3.16 sq ml (8.18 sq km). PERIOD OF RECORD.--Water years 1958-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- 1CAL 0.7 KF AGAR 1NSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 24... 0850 9.1 215 7.40 22.5 750 7.6 91 52 K12000 30000 DEC 05... 0945 6.9 248 7.60 21.0 7.9 91 K15000 50000 FEB 1987 20... 0830 1.5 301 7.60 18.5 11 7.1 78 19 K110000 21000 APR 10... 0925 1.6 252 7.60 22.0 1.4 7.0 83 <10 20000 3000 JUN 12... 0755 3.7 260 7.90 22.5 32 7.4 87 10 2700 13000 AUG 07... 0820 2.6 255 7.60 24.0 1.6 6.8 82 15 5300 2000 HARD- ALKA- RARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 24... 73 5 19 6.3 10 0.5 3.4 68 <0.5 11 10 DEC 05... 87 -- FEB 1987 20... 110 APR 10... 98 2 28 6.8 13 0.6 1.8 96 -0.5 11 11 JUN 07... 100 AUG 12... 100 4 31 6.5 13 0.6 2.8 100 11 11 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEM, GEM, GEM, GEM, 01S- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2-NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 24... 0.1 25 126 3.12 1430 1.67 0.03 1.70 0.06 0.74 DEC 05... 1 1.89 0.01 1.90 0.16 0.94 FEB 1987 20... <1 1.15 0.05 1.20 0.14 0.96 APR 10... 0.2 31 160 0.71 6 0.68 0.02 0.70 0.03 0.17 JUN 12... 56 1.19 0.01 1.20 0.05 0.E5 AUG 07... 0.2 31 170 1.2 <1 1.19 0.01 1.20 0.03 0.77 K = non-ideal count 53 RIO GUAJATACA BASIN 50010500 RIO GUAJATACA AT LARES, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PROS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 24... 0.8 2.5 11 0.06 <1 600 <10 <1 <1 20 DEC 05... 1.1 3.0 13 0.80 FEB 1987 20... 1.1 2.3 10 0.17 APR 10... 0.2 0.9 4.0 0.07 2 <100 10 2 <10 <1 JUN 12... 0.7 1.9 0.18 AUG 07... 0.8 2.0 0.07 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) OCT 1986 24... 20000 <5 790 <0.1 <1 <1 220 <0.01 3 0.04 DEC 05... FEB 1987 20... APR 10... 160 <5 100 <0.1 <1 1 <10 <0.01 13 0.03 JUN 12... AUG 07... RIO GUAJATACA BASIN 54 50010600 RIO GUAJATACA ABOVE LAGO GUAJATACA, PR LOCATION.--Lat 18°1957", long 66°5529", Hydrologic Unit 21010002, 1.0 ml (1.6 km) off road 451, 3 mi (5 km) south of [ago Guajataca, 1.0 mi (1.6 km) east of Eneas and 2.0 mi (3.2 km) west of Piletas. DRAINAGE AREA.--Indeterminate. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--July 1984 to current year. GAGE.--Water-stage recorder. Elevation of gage is 565 ft (172 m), from topographic map. REMARKS.--Records fair. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 2,600 ft'is (73.6 m 3/s), May 18, 1985, gage height, 12.03 ft (3.667 m), from rating curve extended above 100 ft3/s (2.83 03/s) on basis of step-backwater analysis: minimum discharge, 1.9 ft'is (0.054 e/s), Feb. 11, 17, 1986. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 1,500 fti/s (42.5 03/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ftVs) (m 3/s) (ft) (m) Date Time (ftVs) (03/s) (ft) (m) Oct. 18 1645 *1,780 50.4 *10.58 3.225 July 27 1830 1,730 49.0 10.48 3.194 May 18 1700 1,520 43.0 10.04 3.060 Minimum discharge, 2.4 ft'is (0.068 m 3/s), Apr. 2. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 6.6 39 283 5.7 6.8 6.6 5.1 94 38 20 14 36 2 5.0 32 105 5.9 6.6 6.6 3.4 85 26 18 12 43 3 57 27 43 5.3 5.6 6.9 4.2 52 98 16 84 119 4 53 27 30 5.4 5.7 7.6 4.0 31 51 15 28 120 5 26 22 22 5.4 5.1 7.8 19 21 43 17 17 61 6 14 21 19 8.4 5.0 6.7 9.7 18 60 13 13 34 7 66 22 17 11 4.7 6.3 36 38 33 11 11 27 8 31 20 16 8.1 4.7 6.1 37 70 22 11 9.8 22 9 48 18 15 6.1 4.7 5.0 17 40 17 11 9.0 44 10 29 16 14 3.7 10 5.6 27 22 15 9.9 8.3 232 11 107 15 12 5.2 57 5.1 82 25 13 9.3 7.7 213 12 56 32 11 5.1 61 5.8 90 27 12 9.3 10 147 13 43 27 11 5.1 22 4.7 54 17 21 8.0 12 96 14 50 16 11 7.3 66 3.7 205 14 14 7.9 7.2 57 15 37 14 11 6.5 43 8.1 246 13 34 10 53 41 16 24 31 9.9 6.5 13 10 168 11 21 9.4 18 34 17 18 36 9.7 6.5 10 10 92 9 8 32 7.4 10 26 18 193 138 9.6 6.5 8.6 6.1 36 163 259 18 42 22 19 219 119 9.0 6.4 7.1 5.5 21 142 91 24 82 31 20 89 48 9.1 6.2 6.7 5.6 15 65 41 11 29 46 21 43 31 8.3 5.8 6.7 4.9 12 30 25 8.7 14 28 22 35 24 8.2 5.7 6.7 4.5 9.2 49 73 16 11 28 23 43 19 7.4 5.7 7.4 4.8 8.2 42 58 129 9.5 23 24 39 18 6.8 5.8 6.9 4.9 7.0 22 32 44 9.2 16 25 35 17 8.5 5.8 6.5 5.2 6.3 289 31 16 8.5 14 26 119 27 5.8 5.7 5.7 5.1 7.0 150 21 17 131 13 27 132 18 5.9 5.7 8.2 4.5 7.5 46 17 219 60 11 28 136 15 6.8 5.5 6.3 4.6 6.4 33 92 87 17 11 29 70 14 8.2 5.4 --- 4.1 69 23 55 31 14 12 30 71 24 5.8 15 3.0 101 17 37 19 16 9.6 31 50 --- 5.9 7.2 3.3 --- 94 --- 15 36 --- TOTAL 1944.6 927 744.9 199.6 407.7 178.7 1405.0 1752.8 1382 857.9 803.2 1616.6 MEAN 62.7 30.9 24.0 6.44 14.6 5.76 46.8 56.5 46.1 27.7 25.9 53.9 MAX 219 138 283 15 66 10 246 289 259 219 131 232 MIN 5.0 14 5.8 3.7 4.7 3.0 3.4 9.8 12 7.4 7.2 9.6 CAL YR 1986 TOTAL 14580.0 MEAN 39.9 MAX 650 MIN 2.2 WTR YR 1987 TOTAL 12220.0 MEAN 33.5 MAX 289 MIN 3.0 55 RIO GUAJATACA BASIN 50010600 RIO GUAJATACA ABOVE LAGO GUAJATACA, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1986 TO SEPTEMBER 1987 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) NOV, 05 1133 21.4 306 23.5 MAY, 06 1132 17.9 387 24.0 DEC, 10 1718 13.6 303 22.0 JUN, 03 1316 20.2 358 24.5 JAN, 14 1243 6.56 318 22.0 JUL, 14 1431 8.14 367 26.0 FEB, 04 1449 5.13 346 22.5 AUG, 05 1206 16.7 337 25.0 MAR, 11 1217 4.58 311 25.0 SEP, 03 1325 20.6 253 24.5 APR, 07 0720 4.26 304 23.0 __ _ 56 RIO GUAJATACA BASIN 50011000 CANAL PRINCIPAL DE DIVERSIONES AT LAGO DE GUAJATACA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°24'02, long 66°5527, off Highway 476 at Lago Guajataca outlet, 3.0 ml (4.8 km) southwest of Segunda Unidad Baldorioty de Castro, and 5.3 ml (8.5 km) south of Quebradillas Plaza. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1958-64, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 04... 1435 50 315 6.80 25.5 1.2 1.3 16 <10 K91 57 DEC 09... 1330 70 330 6.90 25.0 1.5 19 K12 K15 FEB 1987 06... 0800 60 310 7.50 24.5 5.2 4.7 58 14 K4 K5 APR 06... 1540 60 287 7.20 25.5 0.8 2.9 36 12 K1 K1 JUN 09... 1045 60 284 7.40 26.0 1.2 1.4 18 <10 28 28 AUG 04... 1020 45 250 6.60 26.5 10 1.3 17 <10 K21 K20 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- ,..,IS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 04... 130 4 48 3.3 5.4 0.2 1.8 130 <0.5 9.7 6.6 DEC 09... 140 FEB 1987 06... 130 APR 06... 130 12 47 3.6 5.7 0.2 1.4 120 <0.5 9.5 7.7 JUN 09... 120 AUG 04... 140 11 50 3.9 5.3 0.2 1.7 130 12 7.4 SOLIDS, RESIDUE ELM- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEM, GEM, GEM, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 04... <0.1 7.7 160 21.7 4 0.09 <0.01 <0.10 0.32 0.20 DEC 09... <1 0.09 <0.01 <0.10 0.36 0.24 FEB 1987 06... 4 0.09 <0.01 <0.10 0.08 0.42 APR 06... 0.2 7.2 154 25.0 3 0.09 <0.01 <0.10 0.03 0.57 JUN 09... <1 0.09 <0.01 <0.10 0.06 0.74 AUG 04... 0.1 6.1 164 19.9 <1 1.49 <0.01 <1.50 0.01 0.89 K = non-ideal count 57 RIO GUAJATACA BASIN 50011000 CANAL PRINCIPAL DE DIVERSIONES AT LAGO DE GUAJATACA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA 4- NITRO- NITRO- PROS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 04... 0.8 0.04 2 ,100 <10 <1 <1 <10 DEC 09... 0.6 0.02 FEB 1987 06... 0.5 0.01 APR 06... 0.6 0.03 2 <100 <10 <1 2 <10 JUN 09... 0.8 0.04 AUG 04... 0.9 2.4 11 0.01 -- -- MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLr_ TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) NOV 1986 04... 220 17 270 <0.1 <1 <1 50 <0.01 1 0.04 DEC 09... FEB 1987 06... APR 06... 40 <5 100 <0.1 <1 1 10 <0.01 4 0.01 JUN 09... AUG 04... RIO GUAJATACA BASIN 58 50011200 RIO GUAJATACA BELOW LAGD GUAJATACA, PR LOCATION.--Lat 18°24'01", long 66°55 1 40", Hydrologic Unit 21010002, on left bank, 250 ft (76 m) downstream from bridge on Highway 476, 1,000 ft (305 m) downstream from outlet tunnel, and 5.2 ml (8.4 km) southeast of Quebradillas. DRAINAGE AREA.--Indeterminate. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--August 1969 to December 1970, April 1984 to current year. GAGE.--Water-stage recorder. Elevation of gage is 535 ft (163 m), from topographic map. REMARKS.-- Records fair. Flow regulated by Lago Guajataca Dam. Low flows are from seepage through and under dam and nearby springs. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 1,350 ft'/s (38.2 03/s), May 13, 1986, gage height, 11.97 ft (3.648 m). from rating curve extended above 400 ft'/s (11.3 m'/s) on basis of step-backwater analysis; minimum discharge. 0.53 ft'/s (0.015 m'A). May 31. June 1, 1984. EXTREMES FOR CURRENT YEAR.--Maximum discharge, 451 ft'is (12.8 10/s), April 20, gage height, 9.39 ft (2.862 m); minimum discharge, 0.70 ft'/s (0.020 10/s), May 23-25. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 1.4 1.4 1.6 1.4 1.2 1.1 1.6 1.2 1.1 147 1.9 2.5 2 1.5 1.4 1.5 1.4 1.1 1.1 1.5 1.0 1.1 149 1.8 2.5 3 1.8 1.4 1.4 1.4 .94 1.2 1.4 .90 1.3 154 1.9 2.5 4 1.6 1.4 1.4 1.4 1.1 1.3 1.2 62 1.3 165 1.9 2.4 5 1.5 1.4 1.4 1.5 1.4 1.3 1.2 175 1.3 163 1.9 2.2 6 1.4 1.5 1.4 1.8 1.6 1.3 1.1 186 1.4 162 1.9 2.2 7 1.7 1.4 1.4 1.7 1.5 1.2 1.2 185 1.3 64 1.9 2.2 8 1.4 1.4 1.4 1.5 1.4 1.2 1.1 185 1.4 1.8 1.9 2.2 9 1.4 1.3 1.6 1.4 1.4 1.1 1.1 184 1.4 1.9 1.9 2.0 10 1.3 1.3 1.6 1.4 1.6 1.3 1.1 184 1.4 1.9 2.0 1.9 11 1.4 1.3 1.5 1.4 1.9 1.1 1.2 66 1.4 2.1 2.1 2.3 12 1.3 1.3 1.5 1.4 1.6 1.0 1.6 .91 1.4 2.1 2.1 2.2 13 1.3 1.3 1.4 1.5 1.5 1.1 1.5 .84 1.4 2.0 2.1 2.2 14 1.3 1.3 1.3 1.7 1.4 1.0 36 .85 1.4 2.0 2.4 2.3 15 1.3 1.3 1.3 1.5 1.4 1.1 241 .82 1.3 2.2 2.1 2.3 16 1.3 1.3 1.4 1.4 1.3 1.1 361 .81 1.3 2.1 2.1 2.3 17 1.5 1.3 1.4 1.5 1.3 1.2 362 .81 1.3 1.9 2.1 2.2 18 1.7 1.3 1.3 1.4 1.4 .95 360 .80 1.9 1.8 2.2 2.2 19 2.1 1.4 1.3 1.4 1.4 1.0 357 .77 88 1.8 2.3 2.3 20 1.6 1.6 1.3 1.5 1.4 1.0 391 .77 142 2.0 2.2 2.5 21 1.4 1.4 1.3 1.6 1.4 1.0 429 .78 143 2.2 2.2 2.4 22 1.3 1.3 1.3 1.6 1.3 1.0 232 .74 143 2.1 2.1 2.4 23 1.4 1.4 1.3 1.6 1.3 1.0 132 .70 143 2.1 2.1 2.5 24 1.4 1.4 1.3 1.6 1.4 1.0 56 .70 144 2.0 2.1 2.5 25 1.3 1.6 1.4 1.6 1.4 1.2 .87 .71 145 1.9 2.5 2.5 26 1.3 1.6 1.4 1.6 1.4 1.2 .85 .81 144 1.8 2.6 2.2 27 1.5 1.4 1.4 1.7 1.4 1.2 .83 1.1 144 1.8 2.5 2.2 28 1.5 1.4 1.4 1.5 1.2 1.1 1.0 1.2 146 1.8 2.5 2.3 29 1.4 1.4 1.4 1.4 --- 1.0 1.0 1.2 146 1.8 2.5 2.6 30 1.4 1.4 1.6 1.4 1.1 2.2 1.2 146 1.9 2.5 2.6 31 1.4 --- 1.6 1.4 1.4 --- 1.1 --- 1.9 2.5 --- TOTAL 45.1 41.6 43.8 46.6 38.64 34.85 2980.55 1247.72 1698.4 1050.9 66.8 69.6 MEAN 1.45 1.39 1.41 1.50 1.38 1.12 99.4 40.2 56.6 33.9 2.15 2.32 MAX 2.1 1.6 1.6 1.8 1.9 1.4 429 186 146 165 2.6 2.6 MIN 1.3 1.3 1.3 1.4 .94 .95 .83 .70 1.1 1.8 1.8 1.9 CAL YR 1986 TOTAL 27032.04 MEAN 74.1 MAX 1110 MIN .71 WTR YR 1987 TOTAL 7364.56 MEAN 20.2 MAX 429 MIN .70 59 RIO GUAJATACA BASIN 50011200 RIO GUAJATACA BELOW LAGO DE GUAJATACA, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1986 TO SEPTEMBER 1987 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA­ DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) NOV, 04 0813 1.40 360 26.0 APR, 07 1158 1.16 343 27.0 DEC, 12 0856 1.52 303 25.5 MAY, 06 1345 188 276 26.0 JAN, 14 1507 1.76 356 25.0 JUN, 06 1150 1.25 384 27.0 FEB, 05 1327 1.38 327 26.0 AUG, 03 1316 1.83 376 26.0 MAR. 11 1433 1.05 361 26.0 SEP, 02 1512 2.52 345 27.0 RIO GUAJATACA BASIN 60 50011400 RIO GUAJATACA ABOVE MOUTH NEAR QUEBRADILLAS, PR LOCATION.--Lat 18°2831, long 66°57'46", Hydrologic Unit 21010002, on left bank at ford 1.7 ml (2.7 km) upstream from bridge on Highway 2, 1.6 mi (2.6 km) west of Quebradillas plaza, 2.1 ml (3.4 km) upstream from the Atlantic Ocean, and 6.6 ml (10.6 km) downstream from Lago Guajataca. DRAINAGE AREA.--Indeterminate. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February to May 1969 (monthly measurements only), July 1969 to December 1970, April 1984 to current year. GAGE.--Water-stage recorder. Elevation of gage is 0.0 ft (0.0 m), from topographic map. REMARKS.--Records poor. Flow regulated by lago Guajataca 6.6 ml (10.6 km) upstream. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 6,200 ft'is (176 10/s), May 13, 1986, estimated based on a mean daily discharge correlation with station 50011200, 6.5 miles upstream; minimum discharge, 6.2 ft'is (0.176 m'/s), Sept. 4, 9-12, 1984 EXTREMES FOR CURRENT YEAR.--Maximum discharge, 4,730 ft'is (134 m'/s), Mar 16; minimum daily discharge, 6.0 ft'/s (0.170 e/s), Jan. 16, during period of estimated record. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 15 e16 14 12 e7.2 e7.0 e9.5 e14 17 91 16 e18 2 e15 e16 33 12 e7.2 e7.8 e9.5 ell 17 88 16 e18 3 e14 e16 14 14 e7.2 e7.0 e9.5 el0 25 86 16 e18 4 15 e16 13 22 e7.2 e7.0 el() el60 25 99 15 e22 5 17 e16 12 11 e7.2 e7.6 e9.8 eln 19 94 15 19 6 15 25 12 e7.9 e7.0 e7.6 9.9 e190 30 89 15 18 7 22 17 11 e7.2 e7.2 e7.6 10 e190 25 66 15 18 8 28 17 11 e7.2 el0 e8.4 10 e190 20 18 15 18 9 17 17 11 e8.0 e9.0 e8.4 11 184 18 17 15 18 10 23 17 11 e8.0 11 e8.4 11 173 17 17 15 e18 11 e19 16 11 e8.0 71 e8.4 11 121 17 17 17 e19 12 e16 17 11 e7.0 280 e7.0 15 26 16 19 21 e50 13 e15 19 11 e7.0 85 e8.1 72 19 17 17 21 26 14 e15 17 11 e7.0 24 e8.1 163 17 17 17 22 20 15 el5 15 11 e7.0 28 ell 422 16 32 18 23 21 16 e16 20 15 e6.2 12 el90 1190 16 19 18 e27 e22 17 e18 el5 14 e7.0 12 218 862 16 17 17 e27 19 18 e20 e13 11 e6.8 12 11 434 16 163 17 e27 20 19 e25 e12 11 e6.4 12 9.8 316 16 309 17 e28 e19 20 e18 e19 11 e6.4 11 ell e350 16 135 21 e18 e136 21 e16 13 ell e6.6 11 9.7 el100 17 108 18 e16 80 22 e15 e12 ell e6.6 11 el0 e450 17 129 18 e16 25 23 e16 e12 el0 e6.6 13 el0 el60 18 132 18 e15 22 24 e16 12 ell e6.8 14 el0 e90 19 99 20 e15 e20 25 e15 12 11 e6.8 e7.0 el0 el0 18 97 18 el5 e22 26 e15 13 12 e6.8 e7.0 el0 e9.8 19 96 18 e18 e22 27 el7 13 12 e7.7 e7.0 el0 e9.7 19 93 17 e19 e20 28 e17 12 12 e7.2 e7.0 el0 e12 19 185 18 e18 e19 29 e16 12 12 e7.2 --- el0 e12 19 186 17 e18 e19 30 e16 12 12 e7.2 e13 e20 19 100 16 e18 e23 31 e16 --- 12 e7.2 9 6 --- 23 --- 16 e18 --- TOTAL 533 459 385 254.8 704.2 671.5 5808.7 1798 2180 1037 570 809 MEAN 17.2 15.3 12.4 8.22 25.1 21.7 194 58.0 72.7 33.5 18.4 27.0 MAX 28 25 33 22 280 218 1190 190 309 99 28 136 MIN 14 12 10 6.2 7.0 7.0 9.5 10 16 16 15 18 CAL YR 1986 TOTAL 63410.9 MEAN 174 MAX 4300 MIN 8.8 WIR YR 1987 TOTAL 15210.2 MEAN 41.7 MAX 1190 MIN 6.2 e Estimated 61 R10 GUAJATACA BASIN 50011400 RIO GUAJATACA ABOVE MOUTH NEAR QUEBRADILLAS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UN-ME (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 05... 1610 17 515 7.20 25.5 3.5 9.1 112 <10 K64 600 DEC 12... 0945 11 592 7.30 23.5 0.4 6.0 71 <10 K73 260 FEB 1987 03... 1455 7.1 613 7.30 24.5 0.5 8.7 105 <10 K50 K110 APR 06... 1315 9.8 572 7.20 26.0 0.3 7.4 92 <10 K10 K4 JUN 09... 1330 19 470 7.60 25.0 1.3 7.4 89 <10 K110 240 AUG 4... 1340 15 463 7.40 26.5 0.6 10.3 128 37 K31 96 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 5... 210 25 74 7.2 15 0.5 1.1 190 <0.5 9.4 26 DEC 12... - 220 FEB 1987 03... 200 APR 6... 250 28 83 9.9 26 0.8 1.1 220 <0.5 9.9 54 JUN 09... 190 AUG 04.., 210 19 71 7.7 17 0.5 1.2 190 9.0 28 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONST1- 01S- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) 5IO2) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 05... <0.1 6.6 253 11.6 <1 1.49 0.01 1.50 0.21 0.68 DEC 12... 1 2.29 0.01 2.30 0.01 0.99 FEB 1987 03... 1 2.29 0.01 2.30 0.02 0.28 APR 06... 0.1 6.2 322 8.34 6 2.49 0.01 2.50 0.03 0.87 JUN 09... 4 1.79 0.01 1.80 0.04 0.36 AUG 04... 0.1 6.4 254 10.5 3 0.09 0.01 1.00 0.17 0.83 K non-ideal count 62 RIO GUAJATACA BASIN 50011400 RIO GUAJATACA ABOVE MOUTH NEAR QUEBRADILLAS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GIN, GEM, PHOROOS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 05... 0.7 2.2 0.01 <1 <100 <10 <1 <1 <10 DEC 12... 1.0 3.3 15 <0.01 - FEB 1987 03... 0.3 2.6 12 0.01 APR 06... 0.9 3.4 15 0.01 <1 <100 20 <1 4 <10 JUN 09... 0.4 2.2 9.7 0.03 - AUG 04... 1.0 2.0 0.02 - MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LINE TOTAL TOTAL TOTAL TOTAL SELF- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) NOV 1986 05... 130 <5 30 <0.1 (1 <1 10 <0.01 2 0.05 DEC 12... FEB 1987 03... APR 06... 70 <5 30 <0.1 <1 1 <10 <0.01 3 0.11 JUN 09... AUG 04... 63 A TL ANTI C OCEAN JATILL0 a CAMuvak CX/EBRADILLAS 203W 0157 ,q.'0148 Drainage boundaries indetreninate in limestone ter-reit , .Bayaney ....._ r River underground LARES Geojot a bac* ? Rio Tonatea- Rio Grande de Arecibo bd., S ARECIBO Limestone Igneous and sedimentary rocks OTUADO a WO Grande de Drainage boundary Aftasco Satin EXPLANATION A 0148 SURFACE-WATER STATION AND NUMBER • 203 WELL AND WELL NUMBER area FA,ARDe ouci CAGUA$. 2 4 5 KILOMETERS r , 1 5 MtLk5 3 4 Figure 12.--Rio Camuy basin. RIO CAMUY BASIN 64 50014800 RIO CAMUY NEAR BAYANEY, PR LOCATION .--Lat 18•23 1 48", long 66°49 1 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 is 341 ft (104 m), from topographic map. REMARKS.--Records fair. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 6,450 ft'is (183 m 3 /s). Oct. 7, 1985, gage height, 17.66 ft (5.383 m), from rating curve extended above 300 ft'is (8.50 m 3/s) on basis of step-backwater analysis; minimum discharge, 28 ft'is (0.79 10/s), Mar, 15-17, 1985. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 2,000 ftYs (56.6 m'/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (W/s) (m 3/s) (ft) (m) Date Time (W/s) (m0/s) (ft) (m) June 28 1645 *2,730 77.3 *13.12 3.999 Minimum discharge, 31 ft'is (0.878 m'is) , all or part of each day Mar. 28 to Apr. 3. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 52 87 286 55 50 41 31 280 111 108 60 64 2 49 80 300 53 46 39 31 215 96 96 54 85 3 64 74 139 53 43 39 37 157 114 89 62 86 4 159 83 109 52 43 39 41 98 87 87 74 110 5 169 71 99 52 42 38 65 76 101 94 62 114 6 100 73 93 52 42 38 40 67 212 79 52 83 7 169 72 89 60 41 36 51 72 129 77 50 84 8 111 71 85 57 40 36 58 129 93 76 49 85 9 93 70 82 55 40 36 35 100 82 80 49 67 10 85 67 81 51 89 35 39 70 77 75 47 169 11 78 67 79 50 324 34 227 107 72 70 46 304 12 125 79 78 47 370 34 472 102 68 66 44 427 13 77 100 76 47 152 34 283 72 67 64 56 253 14 89 75 76 49 97 34 204 65 66 62 45 133 15 94 70 76 52 111 49 315 61 72 60 65 114 16 82 128 75 49 76 44 388 57 92 67 54 107 17 66 153 72 46 67 69 295 51 99 59 46 97 18 169 339 70 46 56 40 131 181 240 57 44 82 19 282 598 67 44 53 37 92 196 222 89 60 99 20 210 257 66 44 50 38 77 90 102 73 66 168 21 105 149 65 44 48 36 69 93 97 63 53 106 22 87 132 64 44 46 35 66 141 189 57 44 105 23 101 111 63 42 45 34 60 139 142 55 43 95 24 126 97 61 43 43 33 54 92 153 55 42 80 25 83 91 61 43 43 32 50 261 116 52 43 73 26 126 88 62 41 42 33 46 200 89 46 71 70 27 155 91 61 41 50 33 44 105 80 210 86 67 28 185 80 58 41 43 31 44 87 436 205 56 64 29 173 79 58 42 --- 31 44 88 293 89 47 66 30 120 82 57 67 31 293 76 142 68 47 63 31 105 --- 56 63 31 --- 131 --- 63 64 --- TOTAL 3689 3614 2764 1525 2192 1150 3682 3659 3939 2491 1681 3520 MEAN 119 120 89.2 49.2 78.3 37.1 123 118 131 80.4 54.2 117 MAX 282 598 300 67 370 69 472 280 436 210 86 427 MIN 49 67 56 41 40 31 31 51 66 46 42 63 CAL YR 1986 TOTAL 52490 MEAN 144 MAX 1700 MIN 29 WTR YR 1987 TOTAL 33906 MEAN 92.9 MAX 598 MIN 31 65 RIO CAMUY BASIN 50014800 RIO CAMUY NEAR BAYANEY, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1986 TO SEPTEMBER 1987 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) NOV, 03 1251 73.6 309 24.0 APR, 06 1353 37.8 333 25.0 DEC, 09 1250 36.5 278 23.0 MAY, 05 1247 74 311 24.0 JAN, 13 1327 46.1 320 23.0 JUN, 02 1250 78.3 284 24.5 FEB, 03 1411 42 286 23.0 AUG, 04 1207 67.4 281 24.5 MAR, 10 1252 35.6 313 23.0 SEP, 01 1417 60.5 270 25.0 RIO CAMUY BASIN 66 50015700 RIO CAMUY NEAR HATILLO, PR LOCATION.--Lat 18°27'44", long 664956", Hydrologic Unit 21010002, 1.8 mi (2.9 km) southwest of Hatillo plaza, and 1.8 mi (2.9 km) southeast of Camuy plaza, 1.2 mi (1.9 km) south of Planta de Purificacion, and 3.3 mi (5.5 km) upstream from Atlantic Ocean. DRAINAGE AREA.--Indeterminate. WATER-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.--Records fair except those for estimated daily discharges, which are poor. EXTREMES FOR PER100 OF RECORD.--Maximum discharge, 10,500 ft'is (297 m 1 /s), Oct. 7, 1985, gage height, 24.75 ft (7.544 m), from rating curve extended above 200 ft'/s (5.66 03 /s) on basis of step-backwater analysis: minimum discharge, 36 ft'/s (1.02 m'/s), Mar. 19, 1985. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 2,500 ft'A (70.8 m 3/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft'/s) (m'/s) (ft) (m) Date Time (W/s) (m'/s) (ft) (m) Feb. 12 0300 2,560 72.5 14.91 4.544 Apr. 30 2200 3,320 94.0 16.40 4.999 Apr. 13 0330 3,230 91.5 16.23 4.947 June 28 2000 *4,000 113 *17.59 5.361 Apr. 16 2100 3,400 96.3 16.55 5.044 Minimum daily discharge, 37 ft'/s (1.05 m'/s), Mar. 2, during period of estimated record. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 66 101 213 61 53 56 e38 638 161 140 e90 69 2 64 94 e360 59 54 54 e37 322 117 123 75 90 3 66 89 e210 58 48 53 e40 250 157 114 82 86 4 136 95 e130 58 47 53 e45 134 123 108 97 95 5 221 86 e120 58 46 53 e90 107 116 110 84 168 6 111 95 ell° 59 46 52 57 95 309 99 69 107 7 202 90 e100 66 45 51 51 99 191 98 e62 98 8 152 91 e95 64 44 50 103 179 133 92 e58 102 9 116 91 e92 60 43 51 57 136 117 110 e57 75 10 111 87 e90 57 65 53 57 97 108 103 e58 208 11 80 85 e86 56 631 50 352 142 99 94 e56 424 12 129 87 82 54 1140 49 1410 152 95 85 e56 670 13 83 120 82 55 286 48 1480 101 90 82 e90 402 14 93 91 e81 57 134 51 624 88 89 78 e60 170 15 101 87 e81 63 151 84 608 83 87 76 e94 131 16 97 114 80 57 105 e74 1100 77 120 81 e86 127 17 79 166 77 55 93 e120 1060 69 92 76 e64 115 18 158 206 74 53 81 e64 340 146 407 74 e60 94 19 408 712 73 51 75 e58 200 305 384 e140 e80 87 20 373 402 71 51 70 e60 150 114 142 ell° e84 187 21 143 180 70 51 67 e56 115 122 141 e90 72 131 22 117 162 69 51 66 e54 107 168 312 e80 56 117 23 103 155 67 50 63 e52 84 202 221 e74 54 107 24 149 124 66 49 62 e50 89 225 193 e72 53 91 25 101 117 67 48 60 e47 82 474 175 e66 e58 82 26 117 111 67 48 60 e49 75 468 132 e62 e100 78 27 215 114 67 48 70 e48 71 174 126 e350 ell0 75 28 171 101 64 47 59 e45 69 140 817 e300 e80 72 29 230 101 64 48 --- e42 68 129 661 e200 57 74 30 122 101 63 68 e41 541 121 190 e160 e56 71 31 125 --- 62 65 e39 --- 151 --- ell0 69 --- TOTAL 4439 4255 3033 1725 3764 1707 9200 5708 6105 3557 2227 4403 MEAN 143 142 97.8 55.6 134 55.1 307 184 203 115 71.8 147 MAX 408 712 360 68 1140 120 1480 638 817 350 110 670 MIN 64 85 62 47 43 39 37 69 87 62 53 69 CAL YR 1986 TOTAL 95169 MEAN 261 MAX 5460 MIN 48 WTR YR 1987 TOTAL 50123 MEAN 137 MAX 1480 MIN 37 e Estimated 67 RIO CAMUY BASIN 50015700 RIO CAMUY NEAR HATILLO, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1986 TO SEPTEMBER 1987 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) NOV, 03 1014 88.6 306 23.5 APR, 06 1014 57.5 353 27.0 DEC, 12 1208 82 303 23.5 MAY, 05 1022 108 344 24.0 JAN, 13 1032 54.5 342 22.0 JUN, 02 1012 115 293 24.5 FEB, 03 1125 49 316 22.5 AUG, 04 0912 98.5 316 24.0 MAR, 10 1046 52.5 335 23.5 SEP, 01 1131 71 306 25.0 68 THIS PAGE WAS LEFT BLANK INTENTIONALLY 69 ATLANTICOCEAN HATILL0 ARE B BARCELONE TA 0135 Bayaney • Drainage boundarit-s incletermim.ate in limestone terrone /P,b Limo Ro Comuy basin Ac UTUA•00 JAYUYA Rn Srende de Al.a.co basin ADJUNTAS Drainage -boundary RC° Ina Ro 0E100/ Drainage boundary-iv.---' 020050 botin EXPLANATION Island divide ••/\''•—...\\ i t:r7es A 0284 SURFACE—WATER STATION AND NUMBER Ro 6uoyanilla Ri"o Tonal). 11, 0205 QUALITY—OF—WATER STATION AND NUMBER • basin V 025110 QUALITY—OF—WATER PARTIAL RECORD STATION AND NUMBER • 135 WELL AND WELL NUMBER 3 4 5 KILOMETERS I 2 3 4 5 MILES Figure 13.--Rio Grande de Arecibo basin. 70 RIO GRANDE DE ARECIBO BASIN 50020500 RIO GRANDE DE ARECIBO NEAR ADJUNTAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°1054", long 66°44'12, at Highway 135 bridge, 1.0 ml (1.6 km) upstream from Lago Adjuntas, and 1.5 mi (2.4 km) northwest of Adjuntas plaza. DRAINAGE AREA.--12.7 sq ml (32.9 sq km) this does not include 6.0 sq ml (15.6 sq km) above Lago Garzas. PERIOD OF RECORD.--Water years 1969-74, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER 1TY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 23... 0819 26 274 7.60 21.5 24 7.7 92 24 1150 2600 DEC 04... 0850 67 229 7.30 19.5 8.3 95 1300 2000 FEB 1987 19... 0825 16 343 7.60 18.5 0.5 6.5 73 <10 2700 85000 APR 22... 0835 14 322 7.60 23.5 0.5 7.8 97 <10 580 K42000 JUN 17... 1530 26 276 8.20 29.0 35 7.0 96 31 2300 14000 AUG 25... 1430 E1000 305 7.50 25.0 81 7.9 101 17 20000 370000 RAH- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- S1UM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLO SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 23... 130 30 28 14 44 2 3.8 98 <0.5 13 34 DEC 04... 68 FEB 1987 19... 110 APR 22... 120 6 30 10 21 0.9 1.9 110 <0.5 10 30 JUN 17... 98 _ AUG 25... 88 9 23 7.5 27 1 3.0 79 12 35 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEM, GEM, GEN, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO20403 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 23... <0.1 29 225 15.8 10 0.85 0.05 0.90 0.14 0.16 DEC 04... <1 0.59 0.01 0.60 0.03 0.27 FEB 1987 19... 3 1.06 0.04 1.10 0.09 0.81 APR 22... <0.1 30 199 7.52 <1 0.72 0.08 0.80 0.06 0.74 JUN 17... 363 0.88 0.12 1.00 0.18 0.92 AUG 25... 0.1 22 177 61 1.06 0.04 1.10 0.25 0.65 K non-ideal count E = estimate 71 RIO GRANDE DE ARECIBO BASIN 50020500 RIO GRANDE DE ARECIBO NR ADJUNTAS. PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA 4. NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 23... 0.3 1.2 5.3 0.13 <1 <100 <10 <1 <10 <1 DEC 04... 0.3 0.9 4.0 0.04 FEB 1987 19... 0.9 2.0 8.9 0.10 APR 22... 0.8 1.6 7.1 0.11 <1 <100 <10 <1 <1 <10 JUN 17... 1.1 2.1 9.3 0.23 AUG 25... 0.9 2.0 8.9 0.12 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) OCT 1986 23... 1600 ‹5 160 <0.1 <1 <1 310 <0.01 3 0.03 DEC 04... FEB 1987 19... APR 22... 120 <5 60 0.2 <1 <1 <10 <0.01 4 0.ul JUN 17... AUG 25... -- 72 RIO GRANDE DE ARECIBO BASIN 50025000 RIO GRANDE DE ARECIBO NEAR UTUADO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°1811, long 664159", at bridge near Highway 10 at km 56.4, 0.5 mi (0.8 km) downstream from Rio de Caguana, and 2.5 mi (4.0 km) north of Utuado plaza. DRAINAGE AREA.--66.0 sq mi (170.9 sq km) this excludes 6.0 sq mi (15.5 sq km) upstream from Lago Garzas to Rio Guayanes in the Rio Tallaboa basin. PERIOD OF RECORD.--Water years 1959-74, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 22... 1345 65 202 7.20 27.0 74 7.1 90 15 28000 7600 DEC 03... 1400 199 235 7.60 26.5 7.5 95 K18000 25000 FEB 1987 18... 1300 52 306 7.90 26.5 0.7 7.4 93 <10 1200 670 APR 21... 1345 50 260 7.60 32.0 9 6.9 96 <10 2200 K620 JUN 17... 1225 108 244 8.20 30.0 36 8.0 107 33 K14000 1700 AUG 25... 1125 90 249 7.60 28.5 59 7.4 96 <10 24000 7200 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLO SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 22... 96 21 26 7.5 14 0.6 2.6 75 <0.5 22 15 DEC 03... -- 84 FEB 1987 18... 86 APR 21... 99 14 27 7.7 14 0.6 2.4 85 <0.5 24 13 JUN 17... -- 80 AUG 25... 95 22 25 7.8 14 0.6 2.5 73 23 14 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEN, GEN, GEM, GEM, OIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 22... <0.1 27 159 27.9 88 0.97 0.03 1.00 0.06 0.44 DEC 03... 45 1.02 0.08 1.10 0.19 0.41 FEB 1987 18... - 5 1.35 0.05 1.40 0.08 0.92 APR 21... 0.2 28 170 24.8 23 1.04 0.06 1.10 0.07 0.93 JUN 17... 109 1.57 0.03 1.60 0.07 0.33 AUG 25... 0.1 26 156 37.9 60 1.08 0.02 1.10 0.04 1.20 K non-ideal count 73 RIO GRANDE DE ARECIBO BASIN 50025000 RIO GRANDE DE ARECIBO NEAR UTUADO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABIE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 22... 0.5 1.5 6.6 0.14 <1 <100 <10 <1 3 10 DEC 03... 0.6 1.7 7.5 0.33 -- FEB 1987 18... 1.0 2.4 11 0.15 APR 21... 1.0 2.1 0.16 <1 <100 <10 <1 3 20 JUN 17... 0.4 2.0 0.12 AUG 25... 1.2 2.3 10 0.09 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) OCT 1986 22... 5100 6 210 <0.1 <1 1 130 <0.01 3 0.04 DEC 03... FEB 1987 18... APR 21... 1200 5 60 0.2 <1 1 10 <0.01 14 0.02 JUN 17... AUG 25... 74 RIO GRANDE DE ARECIBO BASIN 50026050 RIO CAONILLAS ABOVE LAGO CAONILLAS NEAR JAVUYA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°1326, long 66°3822, 300 ft (91 m) off Highway 531, 700 ft (213 m) upstream from Lago Caonillas, 3.3 ml (5.3 km) northwest of Jayuya plaza. DRAINAGE AREA.--40.4 sq ml (104.6 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-NF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 23... 1235 31 219 8.00 27.0 1.2 6.3 82 <10 440 K50 DEC 04... 1300 55 175 8.20 24.0 6.9 8.1 99 <10 310 K70 FEB 1987 19... 1140 33 218 8.00 23.0 0.3 8.3 100 <10 1(54 1(190 APR 22... 1210 39 212 8.30 28.0 0.5 7.7 100 <10 1(40 1(10 JUN 18... 0835 77 180 8.00 23.5 3.3 8.2 99 34 2100 350 AUG 26... 0930 37 166 7.70 25.5 26 8.1 102 <10 7500 7100 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- D1S- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 23... 76 6 20 6.3 11 0.6 2.1 70 <0.5 15 11 DEC 04... 63 FEB 1987 19... 69 APR 22... 76 9 20 6.3 11 0.5 1.4 67 <0.5 15 12 JUN 18... 62 AUG 26... 61 3 16 5.2 9.8 0.6 1.6 513 14 9.6 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 23... 0.1 23 130 10.9 2 0.39 0.01 0.40 0.07 0.63 DEC 04... 1 0.49 0.01 0.50 0.03 0.27 FEB 1987 19... 6 0.49 0.01 0.50 0.01 0.59 APR 22... 0.1 23 130 11 1 0.19 0.01 0.20 0.01 0.39 JUN 18... 19 0.59 0.01 0.60 0.03 0.27 AUG 26... 0.1 20 111 11.1 25 0.29 0.01 0.30 0.01 0.99 K = non-ideal count 75 RIO GRANDE DE ARECIBO BASIN 50026050 RIO CAONILLAS ABOVE LAGO CAONILLAS NEAR JAYUYA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA t NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 23... 0.7 1.1 4.9 0.01 <1 <100 <10 <1 <1 <10 DEC 04... 0.3 0.8 3.5 0.05 FEB 1987 19... 0.6 1.1 4.9 0.06 APR 22... 0.4 1.0 0.06 <1 <100 ,10 <1 2 <10 JUN 18... 0.3 0.6 0.07 AUG 26... 1.0 1.3 5.8 0.07 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) OCT 1986 23... 240 5 30 <0.1 <1 <1 50 <0.01 3 0.03 DEC 04... FEB 1987 19... APR 22... 90 15 10 <0.1 <1 <1 10 ,0.01 3 0.01 JUN 18... AUG 26... 76 RIO GRANDE DE ARECIBO BASIN 50027250 RIO GRANDE DE ARECIBO BELOW LAGO DOS BOCAS NEAR FLORIDA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°20'50", long 66°40 402", at pedestrian bridge, 0.7 mi (1.1 km) downstream from Lago Dos Bocas and 6.6 mi (10.6 km) west of Florida plaza. DRAINAGE AREA.--169 sq mi (436 sq km) does not include 6.0 sq mi (15.6 sq km) above Lago Garzas. PERIOD OF RECORD.--Water years 1970-71, 1974 to current year. OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 22... 1050 28 247 7.10 27.0 2.6 4.8 61 <10 92 66 DEC 03... 1100 E500 224 7.10 25.5 4.8 59 K1500 2000 FEB 1987 18... 1055 E1000 230 7.10 24.0 11 4.9 59 <10 230 K140 APR 21... 1110 E1000 238 6.90 25.5 12 4.9 59 17 210 320 JUN 17... 1015 E1000 189 7.20 26.5 11 3.8 47 32 K40 K98 AUG 26... 0910 15 204 7.00 27.5 36 3.5 44 12 2100 K230 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 22... 85 7 23 6.7 11 0.5 2.3 78 <0.5 15 10 DEC 03... 71 FEB 1987 18... 72 APR 21 72 10 20 5.3 9.1 0.5 2.0 62 <0.5 13 9.3 JUN 17... 66 -- AUG 26... 82 7 22 6.5 11 0.5 1.4 75 13 11 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- 015- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE 402+NO3 AMMONIA ORGANIC SOLVED (MG/1 PIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 22.., 0.1 22 137 10.3 3 0.29 0.01 0.30 0.06 0.34 DEC 03... 5 0.69 0.01 0.70 0.03 0.67 FEB 1987 18... 13 0.59 0.01 0.60 0.03 1.1 APR 21... 0.1 22 130 5 0.17 0.03 0.20 0.13 0.37 JUN 17... 17 0.59 0.01 3.60 0.03 1.2 AUG 26... 0.1 20 120 4.86 9 0.63 0.07 0.70 0.21 0.63 K = non-ideal count E = estimate 77 RIO GRANDE DE ARECIBO BASIN 50027250 RIO GRANDE DE ARECIBO BELOW LAGO DOS BOCAS NEAR FLORIDA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 22... 0.4 0.7 3.1 0.02 <1 <100 <10 <1 <1 <10 DEC 03... 0.7 1.4 6.2 0.03 FEB 1987 18... 1.1 1.7 7.5 0.02 - APR 21... 0.7 0.9 0.03 ,1 <100 <10 <1 <1 <10 JUN 17... 1.2 1.8 0.04 AUG 26... 0.5 1.2 0.10 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/I) OCT 1986 22... 160 7 60 <0.1 <1 <1 110 <0.01 2 0.02 DEC 03... FEB 1987 18... APR 21... 1000 5 30 <0.1 <1 <1 10 <0.01 8 0.02 JUN 17... AUG 26... 78 RIO GRANDE DE ARECIBO BASIN 50027750 RIO GRANDE DE ARECIBO ABOVE ARECIBO, PR LOCATION.--Lat 18°2529, long 66°4144", Hydrologic Unit 21010002, 0.8 mi (1.3 km) upstream from Rio Tanama, 4.0 ml (6.4 ka) south of Arecibo and 6.7 mi (10.8 km) above mouth, and 10.2 mi (16.4 km) downstream from Lago Dos Bocas. DRAINAGE AREA.--200 mi 2 (520 km 2 ), 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.--Water-stage recorder. Elevation of gage is 30 ft (9 m), from topographic map. REMARKS.--Records fair. Flow regulated by Lag° Dos Bocas Dam 10.2 mi (16.4 km) upstream. AVERAGE DISCHARGE.--5 years (1983-87), 487 ft'is (13.79 m'/s), 33.07 in/yr (840 mm/yr), 352,800 acre-ft/yr (435 hm 3/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 45,800 ft'is (1,300 m 3/s), May 18, 1)85, gage height, 18.22 ft (5.553 m), from floodmark, from rating curve extended above 2,400 ft'is (68.0 m)/s) on basis of slope-area measurement of peak flow; minimum discharge, 30 ft3/s (0.850 m7s), Mar. 30, 1986. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 4,300 ft'/s (122 10/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft7s) (03/s) (ft) (m) Date Time (W/s) (10/s) (ft) (m) Feb. 12 0145 *2,370 67.1 *6.69 2.039 Minimum discharge, 38 ft'is (1.076 10/s), Mar. 13, 14. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 461 207 704 82 46 180 42 497 742 649 95 67 2 236 66 1100 54 185 50 42 439 937 560 62 50 3 74 272 469 131 263 75 47 281 1600 677 71 664 4 209 330 230 121 323 74 351 397 1260 629 347 736 5 188 88 517 50 314 48 266 459 640 331 258 114 6 819 70 150 75 279 50 467 431 1040 144 561 60 7 811 56 103 119 190 42 98 250 880 86 134 53 8 1040 56 330 657 103 42 56 377 597 65 62 174 9 852 196 160 856 102 144 194 252 579 213 57 399 10 412 420 206 217 78 102 415 153 558 241 55 491 11 485 420 187 126 453 44 697 1170 700 747 130 610 12 96 272 436 323 1220 40 1540 1100 558 287 57 572 13 74 401 505 354 317 38 1560 611 644 70 69 503 14 81 419 145 105 365 41 1120 601 424 371 57 466 15 57 89 81 68 145 164 1170 471 540 295 555 247 16 255 83 179 125 343 55 1300 655 626 291 147 535 17 480 61 196 113 651 54 1530 335 495 531 59 616 18 138 576 86 157 564 47 831 733 479 764 81 567 19 224 1630 80 182 617 105 304 795 527 376 405 243 20 221 1560 147 250 581 161 562 1180 447 599 761 272 21 273 1060 76 72 205 477 547 666 561 133 445 249 22 97 282 350 483 183 190 610 613 814 385 74 469 23 371 197 730 180 233 314 516 518 816 585 167 460 24 237 317 409 218 147 414 482 577 1010 143 570 596 25 74 83 162 121 52 191 155 857 533 76 99 293 26 107 66 319 387 73 104 227 852 248 62 67 85 27 160 68 223 73 191 87 389 678 273 271 570 121 28 114 57 126 55 342 52 430 731 421 586 637 414 29 596 464 150 49 --- 61 452 691 771 635 95 205 30 893 190 147 53 47 491 499 777 529 190 191 31 885 --- 119 52 43 --- 502 --- 257 272 --- TOTAL 11020 10056 8822 5908 8565 3536 16891 18371 20497 11588 7209 10522 MEAN 355 335 285 191 306 114 563 593 683 374 233 351 MAX 1040 1630 1100 856 1220 477 1560 1180 1600 764 761 736 MIN 57 56 76 49 46 38 42 153 248 62 55 50 AC-FT 21860 19950 17500 11720 16990 7010 33500 36440 40660 22980 14300 20870 CFSM 1.78 1.68 1.42 .95 1.53 .57 2.82 2.96 3.42 1.87 1.16 1.75 IN. 2.05 1.87 1.64 1.10 1.59 .66 3.14 3.42 3.81 2.16 1.34 1.96 TOTAL 180400 MEAN 494 MAX 10700 MIN 42 AC-FT 357800 CFSM 2.47 IN. 33.55 WTR YR 1987 TOTAL 132985 MEAN 364 MAX 1630 MIN 38 AC-FT 263800 CFSM 1.82 IN. 24.74 CAL YR 1986 79 RIO GRANDE DE ARECIBO BASIN 50027750 RIO GRANDE DE ARECIBO ABOVE ARECIBO, PR-Continued WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1986 TO SEPTEMBER 1987 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) NOV, 18 1014 51.1 288 25.0 MAY, 08 1040 130 245 26.0 DEC. 17 1138 65.8 252 24.0 JUN, 08 1134 157 247 27.0 JAN, 20 1035 88 270 24.0 JUL. 15 0922 141 223 26.5 FEB. 13 1026 107 252 23.5 AUG, 20 1117 90 266 27.0 MAR, 18 1203 46.2 296 25.0 SEP, 15 1056 71 252 27.0 APR, 09 1038 50.3 304 22.5 RIO GRANDE DE ARECIBO BASIN 80 50028000 RIO TANANA NEAR UTUADO, PR LOCATION.--Lat 18°18'02', long 66°4658', Hydrologic Unit 21010001, on downstream side of left abutment of bridge on Highway 111, 1.2 mi (1.9 km) upstream from natural tunnel, 1.5 mi (2.4 km) northeast of Angeles, and 5.8 mi (9.3 km) northwest of Utuado. DRAINAGE AREA.--18.4 mi 2 (47.7 km 2 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--June 1944 to June 1958 (daily stage and two to four measurements per month by Puerto Rico Water Resources Authority), November 1959 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 938.32 ft (286.00 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.--Records fair except those for estimated daily discharges, which are poor. AVERAGE DISCHARGE.--27 years (1961-87), 48.6 ft'A (1.376 mYs), 35.87 in/yr (911 mm/yr), 35,210 acre-ft/yr (43.4 hm'/yr); median of yearly mean discharges, 48 ft'is (1.36 m 3/s), 34,800 acre-ft/yr (43he/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 12,190 ft'/s (345 m'is), 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 ft'/s (14.2 10/s) on basis of slope-area measurement of peak flow; minimum discharge, 6.6 ft'is (0.187 m,/s), June 12, 1977. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 3,000 ft'/s (85.0 m'/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft'/s) (10/s) (ft) (m) Date Time (W/s) (0/s) (ft) (m) Oct. 2 1715 *6,420 182 *14.96 4.560 Minimum daily discharge, 14 ftYs (0.396 m 3 /s). Aug. 29. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 22 35 138 25 27 21 19 e23 55 27 21 34 2 217 34 62 25 25 21 17 e34 169 26 19 31 3 63 40 e49 24 24 20 16 e32 70 25 23 27 4 37 39 e43 24 23 20 40 e22 39 25 20 61 5 45 32 e39 24 23 20 20 e19 59 e28 20 29 6 51 31 38 26 23 20 18 19 81 e22 17 24 7 40 30 37 30 22 19 26 25 45 e20 17 63 8 37 30 36 27 21 19 17 30 36 e32 16 38 9 40 29 35 25 21 18 16 21 33 e21 16 44 10 34 29 35 24 30 18 e18 79 32 e20 16 42 11 49 28 34 23 164 17 e50 48 29 e20 15 53 12 35 57 33 23 80 17 e200 29 29 e19 19 82 13 47 47 32 27 35 16 e120 23 29 e19 19 88 14 43 36 32 25 30 16 e80 21 27 e19 23 47 15 38 31 32 25 30 17 e75 20 54 e23 25 37 16 32 38 32 23 26 18 e130 19 39 e22 17 33 17 28 69 31 23 24 19 e120 19 57 22 16 29 18 28 226 30 22 23 17 e50 48 73 37 102 28 19 38 233 29 21 23 26 e45 31 38 39 44 45 20 27 129 28 21 22 27 e40 23 40 32 20 38 21 24 83 27 21 22 19 e30 30 35 28 16 44 22 25 66 27 21 21 20 e25 48 89 22 15 48 23 25 e59 27 22 21 17 e23 36 44 21 15 38 24 32 e56 27 22 21 17 e21 25 34 20 47 29 25 33 e52 28 21 21 20 e20 30 31 20 39 26 26 30 e64 28 21 22 20 e18 29 29 22 25 25 27 42 e60 26 21 33 18 e17 23 27 32 17 24 28 69 e50 26 22 22 17 e16 22 52 25 15 42 29 51 51 26 27 --- 17 e15 22 34 20 14 30 30 53 74 26 67 17 e20 21 29 19 55 24 31 43 --- 26 30 17 --- 62 --- 23 45 --- TOTAL 1378 1838 1119 782 879 585 1322 933 1438 750 788 1203 MEAN 44.5 61.3 36.1 25.2 31.4 18.9 44.1 30.1 47.9 24.2 25.4 40.1 MAX 217 233 138 67 164 27 200 79 169 39 102 88 MIN 22 28 26 21 21 16 15 19 27 19 14 24 AC-FT 2730 3650 2220 1550 1740 1160 2620 1850 2850 1490 1560 2390 CFSM 2.42 3.33 1.96 1.37 1.71 1.03 2.39 1.64 2.61 1.31 1.38 2.18 IN. 2.79 3.72 2.26 1.58 1.78 1.18 2.67 1.89 2.91 1.52 1.59 2.43 CAL YR 1986 TOTAL 19225 MEAN 52.7 MAX 445 MIN 14 AC-FT 38130 CFSM 2.86 IN. 38.87 WTR YR 1987 TOTAL 13015 MEAN 35.7 MAX 233 MIN 14 AC-FT 25820 CFSM 1.94 IN. 26.31 e Estimated 81 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1958 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED SEDIMENT DISCHARGE: January 1968 to current year. REMARKS.--Sediment samples were collected by a local observer on a weekly basis and during high flow events. Estimates for period of missing daily record were made from a sediment transport curve developed from a period of record over 5 years. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONS: 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 tons (152,000 tonnes) May 18, 1985, minimum daily, 0.0 ton (0.0 tonne) several days during many years. EXTREMES FOR CURRENT YEAR.-- SEDIMENT CONCENTRATIONS: Maximum daily mean, 1,760 mg/L June 02, 1987; minimum daily mean, 2.0 mg/L several days. SEDIMENT LOADS: Maximum daily, 5,930 tons (5,380 tonnes) June 02, 1987; minimum daily, 0.08 ton (0.07 tonne) several days. WATER-QUALITY DATA, WATER YEARS OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (11'/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 24... 1200 27 154 7.40 22.5 14 5.7 68 <10 2500 2900 DEC 05... 1305 39 182 7.80 21.5 8.7 102 200 690 FEB 1987 20... 1130 21 189 8.00 21.0 2.0 9.4 1ULi 22 K40 240 APR 09... 1020 16 173 7.80 23.5 3.0 8.5 104 <10 280 440 JUN 12... 1025 30 168 8.40 24.0 3.2 9.1 112 29 K140 330 AUG 07... 1110 17 160 8.40 26.5 2.6 8.7 112 13 K64 560 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 24... 63 6 15 6.2 11 0.6 2.3 57 <0.5 11 8.7 DEC 05... 56 FEB 1987 20... 57 APR 09... 64 10 16 5.8 8.2 0.5 1.8 54 <0.5 14 8.2 JUN 12... -- 61 AUG 07... 67 9 17 6.0 3.6 0.2 1.9 58 10 8.1 K = non-ideal count 82 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANANA NEAR UTUADO, PR--Continued WATER-QUALITY DATA, WATER YEARS OCTOBER 1986 TO SEPTEMBER 1987 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE. DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 24... <0.1 25 113 8.27 18 0.59 0.01 0.60 0.03 0.77 DEC 05... 0.79 0.01 0.80 0.02 0.48 FEB 1987 20... 22 0.59 0.01 0.60 0.01 0.89 APR 09... 0.1 25 111 4.76 12 0.59 0.01 0.60 0.01 0.69 JUN 12... 11 0.59 0.01 0.60 0.04 0.46 AUG 07... 0.2 25 107 5.01 1 0.29 0.01 0.30 0.01 0.99 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/I. (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 24... 0.8 1.4 6.2 0.02 <1 <100 <10 <1 <1 <10 DEC 05... 0.5 1.3 5.8 0.03 FEB 1987 20... 0.9 1.5 6.6 0.03 APR 09... 0.7 1.3 5.8 0.03 <1 <100 <10 <1 1 10 JUN 12... 0.5 1.1 4.9 0.04 AUG 07... 1.0 1.3 5.8 0.02 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) OCT 1986 24... 740 <5 40 <0.1 <1 <1 100 <0.01 4 0.03 DEC 05... FEB 1987 20... APR 09... 240 <5 30 <0.1 <1 <1 <10 <0.01 14 0.02 JUN 12... AUG 07... 83 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued WATER-QUALITY DATA, WATER YEARS OCTOBER 1986 TO SEPTEMBER 1987 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT SED. SED. SED. SEDI- SUSP. SUSP. SUSP. MENT, FALL FALL FALL STREAM- SEDI- DIS- DIAM. DIAM. DIAM. FLOW, MENT, CHARGE, PERCENT PERCENT PERCENT 1NSTAN- SUS- SUS- FINER FINER FINER DATE TIME TANEOUS PENDED PENDED THAN THAN THAN (CFS) (MG/L) (T/DAY) .002 MM .004 MM .008 MM JUN 1987 02... 1700 1950 35000 184000 3 5 12 02... 1715 1440 14100 54900 6 11 18 02... 1730 1100 7900 23500 10 17 27 SED. SED. SED. SED. SED. SED. SED. SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. FALL FALL SIEVE SIEVE SIEVE SIEVE SIEVE DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. PERCENT PERCENT PERCENT PERCENT PERCENT PERCENT PERCENT FINER FINER FINER FINER FINER FINER FINER DATE THAN THAN THAN THAN THAN THAN THAN .016 MM .031 MM .062 MM .125 MM .250 MM .500 MM 1.00 MM JUN 1987 02... 12 18 40 60 84 96 99 02... 26 37 57 79 92 97 99 02... 38 48 67 89 99 99 99 84 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRAT1ON DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) OCTOBER NOVEMBER DECEMBER 1 22 4 .24 35 16 1.5 138 792 1570 2 217 1450 4890 34 15 1.4 62 65 11 3 63 99 33 40 35 6.6 49 30 4.0 4 37 20 2.0 39 25 2.6 43 20 2.3 5 45 64 17 32 13 1.1 39 13 1.4 6 51 74 26 31 10 .84 38 12 1.2 7 40 30 3.2 30 10 .81 37 12 1.2 8 37 22 3.2 30 10 .81 36 12 1.2 9 40 26 3.2 29 9 .70 35 12 1.1 10 34 15 1.4 29 9 .70 35 15 1.4 11 49 72 19 28 7 .53 34 17 1.6 12 35 18 1.7 57 75 19 33 20 1.8 13 47 75 25 47 48 9.1 32 20 1.7 14 43 30 4.4 36 12 1.2 32 20 1.7 15 38 24 3.3 31 10 .84 32 20 1.7 16 32 13 1.1 38 29 5.0 32 20 1.7 17 28 10 .76 69 176 113 31 17 1.4 18 28 10 .76 226 1110 2590 30 17 1.4 19 38 39 9.6 233 1200 1680 29 16 1.3 20 27 7 .51 129 356 159 28 16 1.2 21 24 6 .23 83 150 34 27 16 1.2 22 25 6 .41 66 70 12 27 16 1.2 23 25 6 .41 59 50 8.0 27 16 1.2 24 32 14 1.4 56 50 7.6 27 16 1.2 25 33 26 4.6 52 50 7.0 28 16 1.2 26 30 17 1.4 64 98 28 28 16 1.2 27 42 43 12 60 81 17 26 16 1.1 28 69 115 41 50 55 7,4 26 16 1.1 29 51 54 11 51 50 6.9 26 15 1.1 30 53 50 14 74 221 140 26 15 1.1 31 43 30 3.5 -- 26 14 .98 TOTAL 1378 5135.32 1838 4862.63 1119 1622.88 85 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) JANUARY FEBRUARY MARCH 1 25 12 .81 27 10 .73 21 4 .23 2 25 11 .74 25 10 .68 21 3 .17 3 24 10 .65 24 10 .65 20 3 .16 4 24 10 .65 23 10 .62 20 3 .16 5 24 10 .65 23 10 .62 20 3 .16 6 26 10 .70 23 10 .62 20 3 .16 7 30 10 .81 22 10 .59 19 3 .15 8 27 10 .73 21 10 .57 19 3 .15 9 25 10 .68 21 10 .57 18 3 .15 10 24 11 .71 30 48 12 18 3 .15 11 23 12 .75 164 818 1490 17 3 .14 12 23 12 .75 80 184 93 17 2 .09 13 22 12 .87 35 16 1.5 16 2 .09 14 21 12 .81 30 15 1.2 16 2 .09 15 21 15 1.0 30 15 1.2 17 2 .09 16 23 15 .93 26 15 1.1 18 3 .15 17 23 16 .99 24 15 .97 19 2 .10 18 22 16 .95 23 15 .93 17 2 .09 19 21 15 .85 23 15 .93 26 13 1.9 20 21 15 .85 22 15 .89 27 10 1.0 21 21 15 .85 22 15 .89 19 3 .15 22 21 15 .85 21 14 .79 20 3 .16 23 22 15 .89 21 12 .68 17 2 .09 24 22 15 .89 21 11 .62 17 2 .09 25 21 12 .68 21 10 .57 20 3 .16 26 21 12 .68 22 12 .71 20 3 .16 27 21 12 .68 33 15 1.3 18 3 .15 28 22 13 .77 22 5 .30 17 3 .14 29 27 15 1.1 -- -- -- 17 3 .14 30 67 150 40 17 2 .09 31 30 10 .81 17 3 .14 TOTAL 782 64.08 879 1615.23 585 6.85 86 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANANA NEAR UTUADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TUNS/DAY) APRIL MAY JUNE 1 19 3 .15 23 5 .31 55 120 56 2 17 3 .14 34 13 1.2 169 1760 5930 3 16 2 .09 32 12 1.0 70 100 27 4 40 95 41 22 4 .24 39 20 2.1 5 20 5 .27 19 3 .15 59 94 34 6 18 2 .10 19 3 .15 81 185 79 7 26 12 .84 25 13 1.8 45 33 4.0 8 17 2 .09 30 21 3.7 36 14 1.4 9 16 3 .13 21 5 .28 33 12 1.1 10 18 2 .10 79 483 496 32 12 1.0 11 50 40 5.4 48 151 29 29 10 .78 12 200 650 351 29 10 .78 29 10 .78 13 120 270 87 23 5 .31 29 9 .70 14 80 110 24 21 3 .17 27 7 .51 15 75 95 19 20 3 .16 51 108 58 16 130 310 109 19 3 .15 39 25 2.6 17 120 270 87 19 3 .15 57 106 61 18 50 40 5.4 48 57 16 73 301 247 19 45 30 3.6 31 20 1.1 38 50 5.1 20 40 21 2.3 23 5 .31 40 20 2.2 21 30 10 .81 30 9 .73 35 22 2.1 22 25 6 .41 48 83 32 89 160 49 23 23 5 .31 36 20 1.9 44 25 3.0 24 21 4 .23 25 6 .41 34 15 1.4 25 20 3 .16 30 10 .81 31 10 .84 26 18 2 .10 29 10 .78 29 9 .70 27 17 2 .09 23 3 .19 27 8 .58 28 16 2 .09 22 2 .12 52 75 28 29 15 2 .08 22 2 .12 34 20 1.8 30 20 3 .16 21 2 .11 29 9 .70 31 --- -- -- 62 136 70 -- -- -- TOTAL 1322 739.05 933 660.13 1438 6602.39 87 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) JULY AUGUST SEPTEMBER 1 27 6 .44 21 4 .23 34 25 2.3 2 26 6 .42 19 3 .15 31 10 .84 3 25 6 .41 23 3 .19 27 9 .66 4 25 10 .68 20 4 .22 61 299 191 5 28 10 .76 20 4 .22 29 10 .78 6 22 7 .42 17 3 .14 24 6 .39 7 20 4 .22 17 2 .09 63 110 49 8 32 54 11 16 2 .09 38 15 1.5 9 21 6 .34 16 2 .09 44 50 12 10 20 3 .16 16 2 .09 42 31 4.9 11 20 3 .16 15 2 .08 53 111 23 12 19 3 .15 19 5 .26 82 258 215 13 19 3 .15 19 4 .21 88 192 108 14 19 2 .10 23 13 2.0 47 30 3.8 15 23 4 .25 25 10 .68 37 15 1.5 16 22 4 .25 17 3 .14 33 12 1.1 17 22 4 .24 16 2 .09 29 9 .70 18 37 47 14 102 784 1500 28 8 .60 19 39 44 8.1 44 73 18 45 51 13 20 32 23 4.7 20 4 .22 38 37 3.8 21 28 10 .76 16 2 .09 44 55 10 22 22 4 .24 15 2 .08 48 63 12 23 37 3 .17 15 2 .08 38 20 2.1 24 39 3 .16 47 199 186 29 9 .70 25 20 3 .16 39 75 24 26 6 .42 26 22 3 .18 25 10 .68 25 6 .41 27 32 46 11 17 2 .09 24 5 .32 28 25 a .54 15 2 .08 42 73 29 29 20 4 .22 14 2 .08 30 15 1.2 30 19 3 .15 55 131 84 24 6 .39 31 23 6 .37 45 52 11 -- -- -- TOTAL 750 56.90 788 1829.37 1203 690.41 88 RIO GRANDE DE ARECIBO BASIN 50028400 RIO TANAMA AT CHARCO HONDO, PR LOCATION.--Lat 18°2452", long 66°4252", on right bank at abandoned power house at Charco Hondo, 1.5 mi (2.4 km) upstream from mouth, and 4 ml (6 km) south of Arecibo. DRAINAGE AREA.--57.6 mi' (149.2 km 2 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--April 1969 to June 1971, October 1981 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 60 ft (18 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Diversion 0.8 mi (1.3 km) upstream for municipal supply of Arecibo. AVERAGE DISCHARGE.--7 years (1970,1982-87), 95.4 ftYs (2.702 40/s), 22.49 in/yr (571 mm/yr), 69,120 acre-ft/yr (85.2 he/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 15,000 ft'is (425 m 3 /s). May 18, 1985, gage height, 17.95 ft (5.471 m), from floodmark, from rating curve extended above 1,000 ft'is (28.3 m'/s) on basis of step-backwater analysis; minimum discharge, 14 ft'/s (0.396 m'/s), Mar. 30, 31, 1987. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 2,000 ft'is (56.6 m'/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (W/s) (m'/s) (ft) (m) Date Time (W/s) (m 3/s) (ft) (m) Oct. 2 1945 *1,610 45.6 *9.54 2.908 Minimum discharge, 14 ft'/s (0.396 03/s), Mar. 30, 31. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 37 55 163 31 31 21 20 49 69 44 29 49 2 157 53 176 30 28 21 18 78 193 39 25 43 3 121 48 99 30 25 22 20 74 151 38 31 57 4 105 61 75 30 24 22 28 50 82 37 28 76 5 e125 48 e62 31 23 22 50 38 71 46 27 85 6 78 51 e61 32 23 21 28 32 179 35 24 66 7 140 49 e59 39 22 20 33 32 146 34 22 72 8 e148 49 e57 34 21 20 60 45 92 38 19 74 9 91 48 e56 33 21 21 20 43 65 48 20 49 10 68 47 e54 29 22 19 20 66 61 41 18 80 11 56 49 e52 29 149 19 140 102 52 32 19 131 12 71 56 e50 28 264 19 478 82 50 27 17 162 13 51 89 e48 30 82 19 279 48 46 26 26 120 14 71 61 e46 38 46 20 172 42 45 25 18 92 15 60 50 e45 32 45 27 166 37 44 27 35 59 16 56 57 e44 29 34 26 292 33 83 34 29 57 17 50 115 e42 27 29 25 273 30 66 26 22 47 18 67 225 41 26 27 22 135 62 112 26 99 41 19 97 509 41 26 25 23 105 105 105 53 140 42 20 e96 233 40 26 23 44 86 49 57 39 66 85 21 e72 139 38 24 23 25 62 68 57 42 32 61 22 68 96 38 24 23 25 55 105 139 31 26 72 23 52 82 37 23 22 21 50 126 95 29 24 77 24 79 72 36 24 21 19 45 66 63 27 27 50 25 56 66 37 22 20 24 42 64 61 27 71 43 26 95 65 37 22 21 25 38 105 47 26 62 38 27 93 75 35 22 31 21 36 71 43 30 35 35 28 85 70 34 22 24 20 35 52 58 39 29 34 29 100 61 34 24 --- 19 33 46 86 29 28 58 30 63 69 33 54 15 44 42 62 25 41 37 31 76 --- 32 36 14 --- 70 --- 26 70 --- TOTAL 2584 2748 1702 907 1149 681 2863 1912 2480 1046 1159 1992 MEAN 83.4 91.6 54.9 29.3 41.0 22.0 95.4 61.7 82.7 33.7 37.4 66.4 MAX 157 509 176 54 264 44 478 126 193 53 140 162 MIN 37 47 32 22 20 14 18 30 43 25 17 34 AC-FT 5130 5450 3380 1800 2280 1350 5680 3790 4920 2070 2300 3950 CFSM 1.45 1.59 .95 .51 .71 .38 1.66 1.07 1.44 .59 .65 1.15 IN. 1.67 1.77 1.10 .59 .74 .44 1.85 1.23 1.60 .68 .75 1.29 CAL YR 1986 TOTAL 35102 MEAN 96.2 MAX 982 MIN 24 AC-FT 69620 CFSM 1.67 IN. 22.67 WTR YR 1987 TOTAL 21223 MEAN 58.1 MAX 509 MIN 14 AC-FT 42100 CFSM 1.01 IN. 13.71 e Estimated 89 RIO GRANDE DE ARECIBO BASIN 50028400 RIO TANAMA AT CHARCO HONDO, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1986 TO SEPTEMBER 1987 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURF DATE TIME INSTANTANEOUS DUCTANCE TURF (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) NOV, 18 1342 90.3 204 23.5 MAR, 18 1646 21.0 268 24.5 DEC, 17 1509 42.8 252 23.5 MAY, 11 1007 61.6 178 24.0 JAN, 20 1327 25.6 292 22.5 AUG, 20 1345 52.2 240 25.0 FEB, 13 1507 76.7 257 23.5 SEP, 15 1254 53.7 263 25.0 90 RIO GRANDE DE ARECIBO BASIN 50029000 RIO GRANDE DE ARECIBO AT CENTRAL CAMBALACHE, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°27'20, long 66°42'10, Hydrologic Unit 21010002, at bridge on unimproved road, about 500 ft (152 m) upstream from Central Cambalache, near Highway 2, 8.3 mi (13.4 km) downstream from Dos Bocas Reservoir, 1.9 mi (3.1 km) downstream from Rio Tanama , and 1.6 mi (2.6 km) southeast of Arecibo. DRAINAGE AREA.--200 sq mi (520 sq km), approximately. PERIOD OF RECORD.--Water years 1963-66, 1969 to current year. OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CIS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 03... 1245 124 354 7.80 26.5 4.7 8.5 106 31 270 K73 DEC 09... 1015 400 294 7.60 24.0 8.1 96 310 330 FEB 1987 06... 1200 126 301 8.10 24.0 2.5 9.5 113 <10 210 K130 APR 24... 0925 E200 299 7.30 25.5 2.7 7.0 86 <10 470 250 JUN 19... 0915 E750 250 7.70 25.0 130 7.3 88 34 K13000 20000 AUG 21 1115 E500 247 7.50 27.5 31 6.4 80 <10 K500 1700 HARD- ALKA- RARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 03... 150 9 50 5.8 8.3 0.3 1.7 140 <0.5 10 10 DEC 09... 110 FEB 1987 06... 110 APR 24... 130 11 43 5.8 8.7 0.3 1.6 120 <0.5 12 11 JUN 19... 100 AUG 21... 100 7 31 6.0 9.4 0.4 2.6 95 12 10 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 03... 0.1 15 185 61.9 3 0.69 0.01 0.70 0.02 0.58 DEC 09... - 2 0.69 0.01 0.70 0.01 0.29 FEB 1987 06... - 4 0.49 0.01 0.50 0.01 0.29 APR 24... 0.1 17 171 5 0.69 0.01 0.70 0.02 1.6 JUN 19... 431 0.39 0.01 0.40 0.01 0.59 AUG 21... 0.1 19 150 41 0.43 0.02 0.50 0.08 0.52 K = non-ideal count E estimate 91 RIO GRANDE DE ARECIBO BASIN 50029000 RIO GRANDE DE ARECIBO AT CENTRAL CAMBALACHE, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 03... 0.6 1.3 5.8 0.05 <1 <100 <10 <1 <1 ,10 DEC 09... 0.3 1.0 4.4 0.03 FEB 1987 06... 0.3 0.8 3.5 0.03 APR 24... 1.6 2.3 10 0.03 <100 <10 <1 13 <10 <1 JUN 19... 0.6 1.0 0.03 AUG 21... 0.6 1.1 0.12 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- N1UM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) NOV 1986 03... 410 <5 70 <0.1 <1 <1 20 <0.01 <1 0.01 DEC 09... FEB 1987 06... APR <5 <1 24... 420 50 0.2 <1 <10 <0.01 6 0.01 JUN 19... AUG 21 PESTICIDE ANALYSES CHLOR- 01- DI- PCB, ALDRIN, DANE, DOD, DDE, DDT, AZINON, ELDRIN DATE TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1987 19... 0915 <0.1 <0.01 <0.1 <0.01 <0.01 <0.01 0.03 <0.01 HEPTA- METH- ENDO- HEPTA- CHLOR MALA- OXY- SULFAN, ENDRIN, ETHION, CHLOR, EPDXIDE LINDANE THION, CHLOR, DATE TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1986 19... <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 0.14 <0.01 NAPH- THA- METHYL METHYL LENES, PARA- TRI- PARA- POLY- PER- TOX- TOTAL THION, THIGH, M1REX, THION, CHLOR. THANE APHENE, TRI­ DATE TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL THION (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1986 19... <0.01 <0.01 <0.01 <0.01 <0.1 <0.1 <1 <0.01 92 THIS PAGE WAS LEFT BLANK INTENTIONALLY 93 41206 BARCELONETA 207 VEGA i3AjA • 0381 MANATI I .208 . 209 VEGA ALTA N 0210 Florida Drainage boundaries indeterminate in limestone terrane 035950 IDA5 //.0 \ /"- • 0350 r• MOROVIG Limestone Igneous and sedimentary rocks Drainage Fti`o CID.° bosin boundar de age boundary Rio Grande R e Arecibo basin R1.6 in a Plato Ontin Island •„ ,rtna ...* de A.^• •t nas and to Rio Jacorjuds Quo* tiosin Ri•O Coomo ucs,r1 Rfa Inaba% oosin Mop im ea .A6 IAN JVAN EXPLANATION A 0350 SURFACE—WATER STATION AND NUMBER V 0307 QUALITY—OF—WATER STATION AND NUMBER • 210 WELL AND WELL NUMBER )MAYANUEZ PO"EN SOMA. • .3 4 5 KILOMETERS I 3 MILES Figure 14.--Rio Grande de Manati basin. 94 RIO GRANDE DE MANATI BASIN 50030700 RIO OROCOVIS NEAR OROCOVIS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°14'20", long 66°2258, at flat low bridge about 300 ft (91 m) northwest of Highway 568, 1.0 ml (1.6 km) north of Orocovis plaza. DRAINAGE AREA.--10.1 sq ml (26.2 sq km). PERIOD OF RECORD.--Water year 1979 to current year. OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 29... 1420 8.1 303 7.70 24.5 3.6 6.9 88 17 K890 310 DEC 17... 1310 6.9 337 7.80 22.0 0.8 7.8 )4 <10 600 230 FEB 1987 12.- 0845 17 264 8.00 20.0 17 8.3 96 <10 6000 23000 APR 15... 1225 E200 172 7.50 23.0 180 8.2 101 18 39000 K120000 JUN 04... 1635 51 211 7.80 23.5 7.8 7.9 98 <10 12000 26000 AUG 24... 1220 7.1 288 8.40 27.0 1.9 9.6 125 11 360 200 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LIN1TY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FEI SULFIDE DIS- DIS- (MG/L TOT FLO SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 29... 120 5 28 11 12 0.5 1.7 110 <0.5 11 11 DEC 17... 120 FEB 1987 12... 85 APR 15... 61 2 15 5.8 8.3 0.5 2.5 59 <0.5 12 11 JUN 04... 65 AUG 24... 130 12 33 12 13 0.5 1.6 120 11 14 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONST1- DIS- AT 105 GEN, GIN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 29... 0.1 31 172 3.76 <1 1.39 0.01 1.40 0.03 0.47 DEC 17... 14 0.99 0.01 1.00 0.01 0.19 FEB 1987 12... 18 1.18 0.02 1.20 0.01 0.49 APR 15... 0.1 20 110 0.0 376 1.06 0.04 1.10 0.08 0.92 JUN 04... 10 0.75 0.05 0.80 0.12 1.2 AUG 24... 0.2 34 190 3.64 4 0.59 0.01 0.60 0.06 0.24 K = non-ideal count E = estimate 95 RIO GRANDE DE MANAT1 BASIN 50030700 RIO OROCOVIS NEAR OROCOVIS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 29... 0.5 1.9 8.4 0.18 1 <100 <10 <1 <1 <10 DEC 17... 0.2 1.2 0.21 FEB 1987 12... 0.5 1.7 7.5 0.17 APR 15... 1.0 2.1 9.3 0.31 <1 100 <10 <1 13 40 JUN 04... 1.3 2.1 0.21 AUG 24... 0.3 0.9 0.27 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) OCT 1986 29... 390 <5 60 0.1 <1 <1 70 <0.01 <1 0.02 DEC 17... FEB 1987 12... APR 15... 10000 5 400 0.2 <1 <1 20 <0.01 5 0.01 JUN 04... AUG 24... RIO GRANDE DE MANATI BASIN 96 50031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR LOCATION.--Lat 18'17'45', 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. DRAINAGE AREA.--55.2 mi, (143.0 km2 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1965 to current year. GAGE.--Water-stage recorder and concrete control. Elevation of gage is 440 ft (134 m), from topographic map. Feb. 2, 1966 to Apr. 27, 1967, staff gage read twice daily. REMARKS.--Records fair except those for estimated daily discharges, which are poor. National Weather Service gage-height telemeter at station. Public water-supply pumpage, about 300 ft (91 m) above the station, influences low-flow discharges. AVERAGE DISCHARGE.--22 years (1966-87), 106 ft'/s (3.002 m'/s), 26.08 in/yr (662 mm/yr), 76,800 acre-ft/yr (94.7 hmYyr); median of yearly mean discharges. 98 ft'/s (2.78 m 3 /s), 71,000 acre-ft/yr (88 hm'/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 48.000 ft'is (1,359 m'/s), May 18, 1985, gage height, 17.89 ft (5.453 m), from floodmarks, from rating curve extended above 200 ft'/s (5.66 m'/s) on basis of computations of flow over broad-crested weir and step-backwater analysis; minimum discharges, 4.4 ft'is (0.125 m3 /s), Apr. 15, 1984 EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 3,500 ft'/s (99.1 m'is) and maximum (*): Discharge Gage height Discharge Gage height Date Time (W/s) (mYs) (ft) (m) Date Time (f0/s) (10/s) (ft) (m) Apr. 11 2330 *6,680 189 *6.88 2.097 June 2 1700 4,570 129 5.75 1.753 Minimum discharge, 21 ft'is (0.595 m3 /s), Feb. 9. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 39 39 57 28 49 30 28 62 201 95 59 60 2 30 57 50 27 37 29 28 59 593 96 52 62 3 31 45 49 25 31 29 26 64 427 95 71 44 4 34 41 45 27 28 30 25 63 259 91 64 47 5 84 54 42 27 26 29 41 56 189 125 71 53 6 98 48 41 28 25 27 216 59 162 90 50 43 7 36 78 39 39 25 26 228 54 151 91 45 38 8 31 93 39 51 24 25 80 81 139 91 45 39 9 29 76 38 40 23 24 51 174 133 83 47 36 10 28 72 36 31 132 24 46 242 129 81 44 36 11 27 101 34 29 514 25 762 230 121 78 43 36 12 26 196 36 28 259 38 1310 219 119 74 49 71 13 25 264 35 28 111 28 431 139 119 71 47 56 14 29 133 46 32 80 26 578 104 110 71 45 45 15 27 89 65 38 71 76 556 85 108 72 56 58 16 e24 83 48 34 54 139 309 74 118 73 56 110 17 e25 122 47 29 44 191 235 69 104 68 42 122 18 e26 179 41 27 41 105 156 315 101 70 93 88 19 e24 207 40 27 36 57 128 269 101 71 83 102 20 e27 197 34 26 34 47 113 345 110 66 47 172 21 45 e93 32 26 33 53 101 395 209 65 41 63 22 51 e70 30 25 31 43 94 369 490 64 39 50 23 41 e63 28 25 30 35 87 287 207 60 38 45 24 82 e54 27 26 29 31 82 232 140 58 37 41 25 67 e56 28 24 29 54 77 338 123 58 45 44 26 91 e71 29 24 31 54 74 400 112 61 54 38 27 95 55 30 23 43 39 72 214 104 59 39 36 28 51 50 29 23 35 33 69 175 102 67 38 34 29 39 54 28 25 --- 32 65 149 100 56 74 34 30 37 65 29 107 31 64 147 98 55 61 36 31 32 --- 29 62 29 --- 271 --- 65 43 --- TOTAL 1331 2805 1181 1011 1905 1439 6132 5740 5179 2320 1618 1739 MEAN 42.9 93.5 38.1 32.6 68.0 46.4 204 185 173 74.8 52.2 58.0 MAX 98 264 65 107 514 191 1310 400 593 125 93 172 MIN 24 39 27 23 23 24 25 54 98 55 37 34 AC-FT 2640 5560 2340 2010 3780 2850 12160 11390 10270 4600 3210 3450 CFSM .78 1.69 .69 .59 1.23 .84 3.70 3.35 3.13 1.36 .95 1.05 IN. .90 1.89 .80 .68 1.28 .97 4.13 3.87 3.49 1.56 1.09 1.17 CAL YR 1986 TOTAL 31805 MEAN 87.1 MAX 2740 MIN 24 AC-FT 63090 CFSM 1.58 IN. 21.43 WTR YR 1987 TOTAL 32400 MEAN 88.8 MAX 1310 MIN 23 AC-FT 64270 CFSM 1.61 IN. 21.83 e Estimated 97 RIO GRANDE DE MANAT1 BASIN 50031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1968 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 29... 1030 34 252 7.60 24.5 23 8.8 106 17 K350 K180 DEC 17... 0950 44 284 8.00 22.5 2.8 8.9 105 <10 230 K170 FEB 1987 12... 1200 E300 194 7.70 22.5 72 8.4 99 11 K7600 43000 APR 15... 0945 420 164 7.50 23.0 69 8.3 99 <10 5100 21000 JUN 04... 1340 230 193 7.90 25.5 12 8.0 100 <10 5100 6400 AUG 20... 1145 46 196 7.60 29.5 180 7.1 71 12 4800 1500 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLO SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 29... 88 8 21 8.7 11 0.5 2.0 80 <0.5 11 12 DEC 17... 100 FEB 1987 12... 66 APR 15... 60 15 14 6.2 9.3 0.5 2.2 46 <0.5 12 11 JUN 04... 60 AUG 20... 81 10 19 8.1 11 0.5 3.2 71 12 11 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 29... 0.1 26 140 12.8 30 1.19 0.01 1.20 0.25 2.4 DEC 17... 11 0.49 0.01 0.50 0.01 0.19 FEB 1987 12... 60 1.67 0.03 1.70 0.06 1.4 APR 15... 0.2 23 105 120 67 1.27 0.03 1.30 0.05 0.85 JUN 04... 16 0.96 0.04 1.00 0.08 1.3 AUG 20... 0.1 23 130 16.1 91 0.76 0.04 0.80 0.10 1.5 K non-ideal count E - estimate 98 RIO GRANDE DE MANATI BASIN 50031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 29... 2.7 3.9 0.48 -1 ,100 <10 <1 <1 10 DEC 17... 0.2 0.7 0.05 FEB 1987 12... 1.5 3.2 14 0.11 - APR 15... 0.9 2.2 9.7 0.16 <1 <100 10 1 12 20 JUN 04... 1.4 2.4 0.12 AUG 20... 8.1 8.9 0.20 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) OCT 1986 29... 1400 <5 60 <0.1 <1 1 20 <0.01 2 0.02 DEC 17... FEB 1987 12... APR 15... 4600 <5 130 0.2 <1 <1 10 <0.01 8 0.01 JUN 04... AUG 20... 99 RIO GRANDE OE MANATI BASIN 50035000 RIO GRANDE DE MANAT1 AT CIALES, PR LOCATION.--Lat 18°1926, long 66°2736, 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 Ai (1.9 km) southeast of Ciales. DRAINAGE AREA.--128 mi' (332 ke), excludes 6.0 mi' (15.5 km 2 ), the runoff from which is diverted through El Guineo and de Matrullas reservoirs. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--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 ka) downstream, drainage area 132 mi' (342 km 2). 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 fair except those for estimated daily discharges, which are poor. National Weather Service gage-height telemeter at station. AVERAGE DISCHARGE.--27 years (1961-87), 266 ft'/s (7.530 m'/s), 28.22 in/yr (717 mm/yr), 192,700 acre-ft/yr (238 hei'/yr); median of yearly mean discharges, 246 ft'/s (6.97 s'/s), 178.000 acre-ft/yr (219 he/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 125,000 ft'/s (3.540 m 3/s), Oct. 9, 1970, gage height, 24.0 ft (7.32 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 (7.32 m), datum then in use; minimum discharge, 20 ft'/s (0.566 m 3/s), Apr. 20, 21. 1984. EXTREMES OUTSIDE PERIOD OF RECORD.--Approximate gage heights of major floods, pointed out by local residents are as follows: August 1899, 50 ft (15.2 m), September 1928, 36 ft (11.0 m), and September 1932, 34 ft (10.4 m) at site 1.6 mi (2.6 km) upstream. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 7,000 ft7s (198 110/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (W/s) (e/s) (ft) (m) Date Time (ft'/s) (m 3/s) (ft) (n) Apr. 12 0200 *25,200 714 *11.92 3.633 June 2 1815 13,700 388 8.99 2.740 May 18 1745 7.150 202 6.67 2.033 Minimum discharge, 43 ft'/s (1.22 m 3/s). Jan. 1. 100 RIO GRANDE DE MANATI BASIN 50035000 RIO GRANDE DE MANATI AT CIALES. PR--Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 69 71 124 60 101 74 74 159 467 171 116 107 2 61 97 100 59 78 69 73 151 2220 165 110 125 3 84 89 93 58 64 68 69 152 1370 166 138 199 4 97 82 87 57 56 68 68 156 697 162 129 140 5 276 95 85 55 52 68 70 139 463 208 126 125 6 306 91 83 70 52 68 1100 141 526 158 103 110 7 110 118 79 136 51 68 744 135 492 155 102 89 8 74 155 79 101 53 66 214 163 360 153 102 103 9 65 131 79 76 54 65 125 465 300 148 101 87 10 60 120 79 65 193 65 93 1040 280 145 96 84 11 58 140 77 60 1250 62 1210 848 257 144 94 92 12 57 257 77 58 756 79 4560 567 237 139 99 207 13 53 525 79 70 235 72 1290 340 232 134 100 173 14 67 212 87 69 222 65 1620 273 221 133 91 126 15 61 146 115 74 188 100 1600 231 224 134 152 137 16 59 148 e140 62 127 334 724 205 265 135 149 152 17 18 68 60 325 440 ell() e100 54 53 106 94 334 213 624 361 192 1440 215 225 127 125 103 230 241 238 19 59 311 e92 51 83 133 287 976 224 128 230 255 20 59 311 e86 49 78 205 244 1080 236 123 116 511 21 68 168 e76 47 77 151 224 1460 446 126 103 159 22 78 130 74 45 75 130 210 1420 1580 124 94 124 23 88 128 74 45 73 91 201 957 552 120 88 115 24 176 119 73 47 70 79 189 735 299 117 87 101 25 138 153 72 47 68 135 177 1020 237 116 113 100 26 198 120 72 44 69 165 166 1260 209 122 143 93 27 147 108 70 43 91 111 160 559 194 119 94 91 28 112 100 69 43 85 90 155 433 185 124 88 87 29 84 97 68 47 --- 84 154 399 178 117 105 88 30 75 110 63 181 79 168 433 177 114 115 93 31 66 --- 61 125 75 --- 643 --- 119 92 --- TOTAL 3033 5097 2623 2051 4501 3466 16954 18172 13568 4271 3609 4352 MEAN 97.8 170 84.6 66.2 161 112 565 586 452 138 116 145 MAX 306 525 140 181 1250 334 4560 1460 2220 208 230 511 MIN 53 71 61 43 51 62 68 135 177 114 87 84 AC-FT 6020 10110 5200 4070 8930 6870 33630 36040 26910 8470 7160 8630 CFSM .76 1.33 .66 .52 1.26 .87 4.42 4.58 3.53 1.08 .91 1.13 IN. .88 1.48 .76 .60 1.31 1.01 4.93 5.28 3.94 1.24 1.05 1.26 CAL YR 1986 TOTAL 83400 MEAN 228 MAX 12500 MIN 47 AC-FT 165400 CFSM 1.79 IN. 24.24 WTR YR 1987 TOTAL 81697 MEAN 224 MAX 4560 MIN 43 AC-FT 162000 CFSM 1.75 IN. 23.74 e Estimated WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1986 TO SEPTEMBER 1987 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA­ DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) NOV, 26 1039 119 204 25.0 MAY, 13 1110 351 175 25.0 DEC, 22 1321 74 202 25.5 JUN. 12 1050 236 209 27.0 JAN, 22 1009 46.4 257 22.5 JUL, 09 1048 148 221 28.0 FEB, 09 1457 54.2 231 28.5 AUG, 06 1030 102 221 28.0 MAR, 25 1014 144 235 26.5 SEP, 14 1119 120 184 28.5 APR, 10 1136 99.4 196 23.0 RIO GRANDE OE MANATI BASIN 101 50035500 RIO GRANDE DE MANATI AT HIGHWAY 149 AT CIALES, RP WATER-QUALITY RECORDS LOCATION.--Lat 18°20'46, long 66°2806", at bridge on Highway 149, about 800 ft (244 m) upstream from confluence with Rio Cialitos, 0.5 ml (0.8 km) north of Ciales plaza. DRAINAGE AREA.--136 sq mi (352 sq km) this excludes the 6 sq mi (15.5 sq km) upstream from Lago El Guineo and Lago de Matrullas, flow from which is diverted to Rio Jacaguas. PERIOD OF RECORD.--Water years 1979 to current year. OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 17... 1225 161 193 8.05 25.5 14 9.0 111 14 K810 770 DEC 23... 1020 68 248 7.55 24.0 5.1 8.1 97 <10 K60 K80 FEB 1987 24... 0955 64 240 7.40 25.0 1.6 7.9 97 <10 K140 K72 APR 24... 1000 166 250 7.50 27.0 0.5 7.8 99 <10 K160 K80 JUN 18... 0915 192 233 8.20 26.0 2.0 8.0 <10 K180 K100 AUG 20 0915 113 169 7.90 27.5 160 5.4 - 13 K9300 3600 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SLUM, WAT WH SULFATE RIDE, TOTAL WH WA! DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 17... 76 1 19 7.0 9.8 0.5 2.0 75 <0.5 11 10 DEC 23... 99 FEB 1987 24... )5 APR 24... 130 37 24 16 74 3 4.5 89 <0.5 12 16 JUN 18... 88 AUG 20... 65 5 16 6.1 8.9 0.5 23 60 11 9.5 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEM, GEM, GEM, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L MG/L (MG/L (MG/L AS F) S102) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 17... 0.1 23 127 55.2 23 0.95 0.05 1.0 0.12 0.48 DEC 23... 11 0.29 0.01 0.30 0.02 0.68 FEB 1987 24... 15 0.39 0.01 0.40 0.03 0.27 APR 24... 0.1 27 227 102 <1 0.59 0.01 0.60 0.02 0.18 JUN 18... 1 0.29 0.01 0.30 0.03 0.37 AUG 20... 0.1 21 110 33.6 9 0.66 0.04 0.70 0.08 0.62 K non-ideal count 102 RIO GRANDE DE MANAT1 BASIN 50035500 RIO GRANDE DE MANATI AT HIGHWAY 149 AT CIALES, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA t NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 17... 0.6 1.6 0.10 <1 <100 20 <1 <1 <10 DEC 23... 0.7 1.0 4.4 0.06 FEB 1987 24... 0.3 0.7 3.1 0.06 APR 24... 0.2 0.8 3.5 0.05 (1 <100 10 <1 9 <10 JUN 18... 0.4 0.7 0.07 AUG 20... 0.7 1.4 0.23 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) NOV 1986 <5 17... 1000 40 0.2 <1 <1 <10 <0.01 <1 0.03 DEC 23... FEB 1987 24... APR 24... 220 <5 20 0.1 <1 <1. <10 <0.01 3 0.01 JUN 18... AUG 20... 103 RIO GRANDE DE MANATI BASIN 50035950 RIO CIALITOS AT HIGHWAY 649 AT CIALES, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°20'18, long 66°2828, 100 ft (30 m) upstream from bridge on Highway 649, 0.7 mi (1.1 km) upstream from mouth, and about 0.4 ml (0.6 km) west of Ciales plaza. DRAINAGE AREA.--17.0 sq ml (44.0 sq km). PERIOD OF RECORD.--Water years 1969-71, 1974 to current year. OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 17... 1415 27 184 7.55 23.5 58 3.8 105 11 5500 7300 DEC 23... 1240 9.2 244 7.75 23.0 3.5 9.0 106 <10 400 790 FEB 1987 24... 1240 7.8 244 7.60 23.0 5.5 8.0 94 44 270 400 APR 24... 1300 21 240 7.80 27.5 1.2 8.2 105 <10 340 230 JUN 18... 1130 31 233 8.60 26.5 1.9 8.6 <10 K970 570 AUG 20.., 1140 18 198 8.20 28.0 17 6.2 15 590 600 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LIN1TY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- BIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLU SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS 504) AS CL) NOV 1986 17... 71 2 20 5.1 8.5 0.5 2.2 69 <0.5 11 8.8 DEC 23... 104 FEB 1987 24... 110 APR 24... 100 0 30 6.6 13 0.6 2.1 110 <0.5 8.9 13 JUN 18... 95 AUG 20... 80 0 22 6.0 9.3 0.5 1.8 80 8.5 9.3 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEM, GEN, GEM, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C, N1TRAIE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) 5IO2) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 17... <0.1 22 119 8.73 64 0.49 0.01 0.50 0.01 0.19 DEC 23... 7 0.69 0.01 0.70 0.01 0.29 FEB 1987 24... 11 0.59 0.01 0.60 0.01 0.69 APR 24... 0.1 29 169 9.70 3 0.69 0.01 0.70 0.01 0.19 JUN 18... 9 1.48 0.02 1.50 0.04 0.16 AUG 20.... 0.2 28 130 8.92 7 0.89 0.01 0.90 0.02 0.38 K = non-ideal count 104 RIO GRANDE DE MANATI BASIN 50035950 RIO CIALITOS AT HIGHWAY 649 AT CIALES, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 17... 0.2 0.7 0.08 <1 100 <10 <1 <1 10 DEC 23... 0.3 1.0 4.4 0.09 FEB 1987 24... 0.7 1.3 5.8 0.13 APR 24... 0.2 0.9 4.0 0.06 <1 <100 <10 <1 3 <10 JUN 18... 0.2 1.7 0.09 AUG 20... 0.4 1.3 0.10 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) NOV 1986 17... 3200 18 80 0.1 ( • s„. \ \\/- j 0449 0 COROZ AL S —Mop area AM JUAN 0444 C., .; \ FAJAROO ,,IAATAeUEZ A .CAGUAS 044 50 fi NARANJI 0 k Ric Cibuto basir;') ,J1 ct Represa de ComertZ, 0440 ft;'o de Boyor.th,ttcl.rt Drainage boundary R IO COM ERIC "sS WO Grand* de nal( baein Drainage boundary ARRAWOUITAS CIDRA \ 4. 1,341, boom 04'30 La Platcy-- A ITO ? Rio 0 Island divide En'o Coonto boatoin CAYEY to EXPLANATION A0469 SURFACE—WATER STATION AND NUMBER 0430 QUALITY—OF—WATER STATION AND NUMBER Rio So nos (Nigua) toosin 399 •399 Logo Carite „.../ ••....•• R±o Grande v 0399 QUALITY—OF—WATER PARTIAL RECORD STATION AND NUMBER .216 WELL AND WELL NUMBER rit 3 I 4 I 5 KILOMETERS 3 4 SMILES de Patinas basin Rif) Guoniafli Tun Rio Goontrm' basin Figure 16.--Rio de la Plata basin. 120 RIO DE LA PLATA BASIN 50043000 RIO DE 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 ml (0.6 km) northeast of Proyecto La Plata, and 2.6 mi (4.0 km) upstream from Rio Usabon. DRAINAGE AREA.--54.8 mi' (141.9 km 2 ), excludes 8.2 ml' (21.1 km') upstream from Carite Reservoir, the flow of which is diverted to Rio Guamani. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--1958 (occasional measurements only), February 1959 to March 1960 (monthly measurements only), April 1960 to current year. GAGE.--Water-stage recorder. Elevation of gage is 850 ft (259 m), from topographic map. Prior to Mar. 29. 1961, wire-weight gage read twice daily at same site and datum. REMARKS.--Records fair. National Weather Service gage-height telemeter at station. 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'is (0.65 m'/s) into Cidra Reservoir. AVERAGE DISCHARGE.--27 years (1961-87), 110 ft 3 /s (3.115 10/s), 27.26 in/yr (692 mm/yr), 79,700 acre-ft/yr (98 hoe/yr); median of yearly mean discharges, 88 ft'/s (2.49 0/s), 63,800 acre-ft/yr (79 he/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 59,600 ft 3 /s (1.690 e/s), Aug. 27, 1961, gage height, 32.21 ft (9.818 m), from rating curve extended above 7,000 ft'/s (198 e/s) on basis of slope-area measurement: minimum daily discharge, 2.6 ft 3 /s (0.074 m'/s), July 25, 1974. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 4,000 ft'/s (113 20/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (W /s) (80/s) (ft) (m) Date Time (W/s) (m'/s) (ft) (m) Nov. 17 1615 *4,440 126 *10.43 3.179 June 21 2115 4,020 114 10.25 3.124 Minimum daily discharge, 8.2 ft 3 /s (0.232 m'/s), Sept. 8. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 22 23 59 47 57 13 9.5 17 47 24 36 19 2 22 24 57 47 34 11 9.4 19 30 20 17 15 3 21 25 64 46 28 12 9.0 21 182 19 85 15 4 20 24 66 45 25 14 8.9 22 86 20 90 12 5 20 62 61 49 24 16 9.1 21 30 142 125 9.9 6 24 68 61 74 23 15 177 28 23 84 79 9.2 7 21 105 74 123 21 11 111 24 20 86 41 8.3 8 20 81 78 71 20 10 40 19 22 43 32 8.2 9 20 59 68 64 20 9.7 26 45 22 30 27 9.7 10 32 50 67 38 23 9.9 23 26 21 25 26 11 11 30 110 105 30 478 11 260 26 17 24 20 10 12 28 1390 109 27 86 10 203 53 16 19 19 10 13 28 364 84 25 276 14 199 29 17 17 17 9.3 14 27 98 107 24 206 10 109 21 17 16 33 9.0 15 34 65 78 30 75 9.1 204 21 18 21 50 9.7 16 50 96 74 25 46 12 90 19 46 28 28 9.3 17 50 533 65 23 36 12 45 17 20 19 18 9.3 18 28 216 62 21 31 11 35 54 17 17 16 58 19 22 116 60 20 29 12 30 24 17 16 25 109 20 18 90 58 20 26 9.5 27 60 251 15 18 130 21 17 79 57 20 24 12 24 97 582 47 16 20 22 26 75 55 21 22 12 22 208 1070 39 14 14 23 24 68 54 22 21 12 21 87 177 20 12 17 24 21 63 53 37 18 12 21 70 59 15 11 13 25 62 64 52 31 15 13 21 101 37 13 11 17 26 45 63 54 25 15 16 20 202 30 13 11 12 27 31 62 53 23 17 15 19 41 25 13 12 10 28 31 63 54 22 17 15 20 26 23 23 10 10 29 24 60 53 21 --- 12 18 38 21 14 11 20 30 22 67 51 138 11 18 32 75 11 11 33 31 22 --- 50 68 10 --- 183 --- 16 10 --- TOTAL 862 4263 2043 1277 1713 372.2 1828.9 1651 3018 909 931 646.9 MEAN 27.8 142 65.9 41.2 61.2 12.0 61.0 53.3 101 29.3 30.0 21.6 MAX 62 1390 109 138 478 16 260 208 1070 142 125 130 MIN 17 23 50 20 15 9.1 8.9 17 16 11 10 8.2 AC-FT 1710 8460 4050 2530 3400 738 3630 3270 5990 1800 1850 1280 CFSM .51 2.59 1.20 .75 1.12 .22 1.11 .97 1.84 .54 .55 .39 IN. .59 2.89 1.39 .87 1.16 .25 1.24 1.12 2.05 .62 .63 .44 CAL YR 1986 TOTAL 20833.0 MEAN 57.1 MAX 1390 MIN 6.2 AC-FT 41320 CFSM 1.04 IN. 14.14 WTR YR 1987 TOTAL 19515.0 MEAN 53.5 MAX 1390 MIN 8.2 AC-FT 38710 CFSM .98 IN. 13.25 121 RIO DE LA PLATA BASIN 50043000 RIO DE LA PLATA AT PROYECTO LA PLATA, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1958 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CIS) (US/CM) UNITS) (D(G C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 20... 1150 18 448 8.50 29.0 2.0 8.9 120 13 K40 K60 DEC 16.., 1130 75 309 7.90 23.5 20 8.4 102 15 K750 K140 FEB 1987 10... 1045 24 444 8.30 24.5 0.7 9.6 119 <10 K160 460 APR 14... 1320 93 328 7.90 27.5 15 7.3 95 17 K1500 K1100 JUN 02... 0920 30 392 8.10 26.5 9.8 7.3 94 <10 2300 3000 AUG 12... 1050 21 446 8.00 29.0 8.6 116 K150 340 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- S1UM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS 5) AS SO4) AS CL) OCT 1986 20... 130 0 31 12 29 1 2.7 130 <0.5 18 26 DEC 16... 100 FEB 1987 10... 150 - APR 14... 110 1 29 9.4 23 1 2.5 110 <0.5 18 23 JUN 02... 150 AUG 12... 36 o 8.6 3.6 9.6 0.7 1.8 100 9.8 10 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONST1- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, D1S- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L OCT 1986 20... 0.2 25 222 10.8 4 0.24 0.06 0.30 0.15 1.9 DEC 16... - 23 0.94 0.06 1.00 0.02 0.48 FEB 1987 10.., 1 1.88 0.02 1.90 0.02 0.68 APR 14... 0.2 22 193 48.5 23 1.09 0.11 1.20 0.12 0.48 JUN 02... 27 1.26 0.04 1.30 0.05 0.55 AUG 12... 0.1 12 162 9.18 11 0.95 0.05 1.00 0.04 0.66 K . non-ideal count 122 RIO DE LA PLATA BASIN 50043000 RIO DE LA PLATA AT PROYECTO LA PLATA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS 8) AS CD) AS CR) AS CU) OCT 1986 20... 2.0 2.3 0.20 1 <100 40 <1 4 10 DEC 16... 0.5 1.5 6.6 0.28 FEB 1987 10... 0.7 2.6 12 0.59 APR 14... 0.6 1.8 8.0 0.36 1 <100 20 <1 5 20 JUN 02... 0.6 1.9 0.35 AUG 12... 0.7 1.7 7.5 0.35 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) OCT 1986 20... 240 <5 30 <0.1 <1 1 70 <0.01 1 0.07 DEC 16... FEB 1987 10... APR 14... 1300 5 70 0.2 <1 <1 10 <0.01 26 0.09 JUN 02... AUG 12... 123 RIO DE LA PLATA BASIN 50044000 RIO DE LA PLATA NEAR COMERIO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°14'33", long 66°12'28', at bridge on Highway 156, 0.56 ml (0.9 km) upstream from dam, about 2.0 mi (3.2 km) northeast of Comerio plaza. DRAINAGE AREA.--139 sq mi (360 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- C1FIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR 1NSTAN- DUCT- (STAND- ATURE BID- 015- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) i0EG C, (FTU) ',!G/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 21... 0930 41 438 7.90 27.0 1.5 7.7 99 28 K100 360 DEC 18... 0950 91 380 8.00 23.0 1.9 8.7 104 <10 370 340 FEB 1987 11... 1420 E800 254 7.60 23.5 130 8.0 97 52 K83000 96000 APR 16... 0825 E300 241 7.60 23.0 64 7.6 91 21 K8100 K12000 JUN 22... 0930 (1600 146 7.60 23.0 200 8.1 96 11 K50000 K110000 AUG 18... 0850 86 375 7.90 27.5 1.3 7.6 97 15 800 1400 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- UNITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT 015- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 21... 140 3 34 14 27 1 2.7 140 <0.5 17 27 DEC 18... 130 FEB 1987 11... 180 APR 16... 85 9 20 8.4 15 0.7 2.7 76 <0.5 14 11 JUN 22... 49 AUG 18... 140 0 33 13 23 0.9 2.6 140 15 25 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C. NITRATE NITRITE NO20103 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 21... 0.1 27 233 25.8 8 1.51 0.08 1.60 0.15 0.75 DEC 18... 17 0.98 0.02 1.00 0.03 0.57 FEB 1987 11... 128 1.33 0.07 1.40 0.17 8.4 APR 16... 0.2 24 141 82 1.33 0.07 1.40 0.09 1.0 JUN 22... 85 0.71 0.09 0.80 0.17 AUG 18... 0.2 26 220 51.1 4 0.98 0.02 1.00 0.04 0.56 K = non-ideal count E = estimate 1.7 124 RIO DE LA PLATA BASIN 50044000 RIO DE LA PLATA NEAR COMERIO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MON1A + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 21... 0.9 2.5 0.31 2 <100 50 1 8 10 DEC 18... 0.6 1.6 7.1 0.24 FEB 198/ 11... 8.6 10 44 0.72 APR 16... 1.1 2.5 11 0.28 <1 100 20 <1 2 20 JUN 22... 1.9 2.7 12 0.43 AUG 18... 0.6 1.6 0.30 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELL- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) OCT 1986 21... 280 <5 30 <0.1 <1 1 70 <0.01 3 0.o5 DEC 18... FEB 1987 11... APR 16... 4700 <5 140 0.2 <1 ,1 10 <0.01 6 0.02 JUN 22... AUG 18... 125 RIO DE LA PLATA BASIN 50044850 RIO GUADIANA NEAR NARANJITO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°1839, long 6613'28, at steel-cross-bridge 0.8 ml (1.3 km) northwest of Highway 164, 1.2 ml (1.9 km) upstream from mouth and about 2.0 ml (3.2 km) northeast of Naranjito plaza. DRAINAGE AREA.--4.0 sq ml (10.3 sq km). PERIOD OF RECORD.--Water year 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 21... 1315 4.5 285 7.80 28.5 3.0 7.5 96 <10 410 540 DEC 18... 1245 9.0 375 8.10 24.0 1.6 8.0 96 <10 - FEB 1987 23... 0945 7.4 369 8.10 21.5 0.4 8.4 96 <10 K810 690 APR 16... 1115 42 280 7.80 25.0 6.0 7.7 )4 <10 K7800 26000 JUN 22... 1105 E100 218 8.00 23.0 58 8.5 99 <10 K65000 K1000000 AUG 18... 1050 8.9 308 8.10 27.5 2.4 8.2 104 <10 K850 470 HARD- AAA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SLUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AF S) AS SO4) AS CL) OCT 1986 21... 130 21 31 13 17 0.7 2.3 110 <0.5 17 25 DEC 18... 120 FEB 1987 23... 120 APR 16... 100 17 22 11 14 0.6 2.0 83 <0.5 20 18 JUN 22... 74 AUG 18... 140 25 31 14 16 0.6 2.0 110 13 21 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, 01S- CONSTI- DIS- AT 105 GEM, GEM, GEM, GEM, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 21... 0.1 27 198 2.36 6 1.38 0.02 1.40 0.06 0.14 DEC 18... - 13 1.37 0.03 1.40 0.08 0.42 FEB 1987 23... 2 1.29 0.01 1.30 0.01 0.69 APR 16... 0.2 26 163 18.5 27 1.59 0.01 1.60 0.02 0.38 JUN 22... -- 167 0.87 0.03 0.90 0.05 0.45 AUG 18... 0.1 27 190 4.52 6 1.19 0.01 1.20 0.01 0.39 K = non-ideal count E = estimate 128 RIO DE LA PLATA BASIN 50044850 RIO GUADIANA NEAR NARANJITO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, :ADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 21... 0.2 1.6 0.24 1 100 <10 <1 5 <10 DEC 18... 0.5 1.9 8.4 0.22 FEB 1987 23... 0.7 2.0 8.9 0.17 - APR 16... 0.4 2.0 8.9 0.17 <1 <100 20 <1 7 20 JUN 22... 0.5 1.4 6.2 0.31 AUG 18... 0.4 1.6 7.1 0.19 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) OCT 1986 21... 260 <5 30 <0.1 <1 1 130 <0.01 2 0.05 DEC 18... FEB 1987 23... APR 16... 1300 <5 50 0.1 <1 <1 <10 <0.01 6 0.05 JUN 22... AUG 18... 127 RIO DE LA PLATA BASIN 50046000 RIO DE LA PLATA AT TOA ALTA, PR (National stream-quality accounting network station) WATER-QUALITY RECORDS LOCATION.--Lat 18°2441", long 66°1539", at Highway 2, 1.3 mi (2.1 km) downstream from Rio Lajas, and 1.6 ml (2.6 km) northwest of Toa Alta, 11.3 ml (18.2 km) downstream from Puerto Rico Aqueduct and Sewer Authority reservoir. DRAINAGE AREA.--208 sq ml (539 sq km), exclude 8.2 sq ml (21.2 sq km) upstream from Lago Carite, flow from which is diverted to Rio Guamani. PERIOD OF RECORD.--Water years 1958 to current year WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, COLI- STREP- SPE- DIS- FORM, TOCOCC1 HARD- STREAM- CIFIC SOLVED FECAL, FECAL, NESS FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- 0.7 KF AGAR TOTAL 1NSTAN- DUCT- (STAND- ATURE BID- DIS- CENT UM-MF (COLS. (MG/L DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- (COLS./ PER AS (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) 100 ML) 100 ML) CAC03) OCT 1986 16... 1250 26 520 7.70 30.5 1.0 10.2 137 510 K30 190 DEC 26... 1020 44 421 7.40 25.5 2.9 5.4 66 3600 K1300 180 FEB 1987 13... 1135 376 38 7.60 25.0 54 6.3 77 K16000 23000 130 APR 29... 1040 55 425 7.70 29.5 1.7 10.6 139 3600 K90 180 JUN 03... 1345 1600 320 7.70 26.5 53 7.5 93 K1500 3400 88 AUG 11... 1310 61 435 7.50 27.5 2.4 8.3 105 K740 K2O 170 HARD- ALKA- NESS MAGNE- POTAS- LINITY CHLO- FLUO- SILICA, NONCAR8 CALCIUM SIUM, SODIUM, SODIUM SIUM, WAT WH SULFATE RIDE, RIDE, DIS- WH WAT DIS- DIS- DIS- AD- DIS- TOT FET DIS- DIS- D1S- SOLVED TOT FLD SOLVED SOLVED SOLVED SORP- SOLVED FIELD SOLVED SOLVED SOLVED (MG/L DATE (MG/L AS (MG/L (MG/L (MG/L TION (MG/L MG/L AS (MG/L (MG/L (MG/L AS CAC03) AS CA) AS MG) AS NA) RATIO AS K) CAC03 AS SO4) AS CL) AS F) 5IO2) OCT 1986 16... 23 58 11 27 0.9 3.9 168 20 31 0.1 18 DEC 26... 18 53 11 19 0.6 2.7 160 21 26 0.1 19 FEB 1987 13... 11 37 9.4 16 0.6 3.4 120 18 22 0.2 16 APR 29... 16 56 10 18 0.6 2.6 165 20 18 0.1 18 JUN 03... 7 23 7.5 12 0.6 2.6 82 13 15 0.2 19 AUG 11... 0 47 12 20 0.7 2.6 159 14 24 0.2 21 SOLIDS, SOLIDS, NITRO- NITRO- NITRO- NITRO- PHOS- PHOS- RESIDUE SUM OF SOLIDS, GIN, GIN, GEN, GEN,AM- PHOS- PHOROUS PRATE, AT 180 CONSTI- DIS- NO2+NO3 AMMONIA AMMONIA MONIA + PHOS- PHOROUS ORTHO, ORTHO, DEG. C TUENTS, SOLVED DIS- DIS- DIS- ORGANIC PHOROUS DIS- DIS- DIS- DIS- DIS- (TONS SOLVED SOLVED SOLVED TOTAL TOTAL SOLVED SOLVED SOLVED DATE SOLVED SOLVED PER (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L) (MG/L) DAY) AS N) AS N) AS NH4) AS N) A P) AS P) AS P) AS PO4) OCT 1986 16... 336 270 19.0 0.32 0.08 0.8 0.18 0.09 0.06 DEC 26... 250 252 29.7 0.80 0.19 0.24 0.9 0.17 0.15 0.12 0.37 FEB 1987 13... 205 197 208 0.45 0.15 0.19 0.9 0.19 0.09 0.09 0.28 APR 29... 248 243 36.6 0.29 <0.01 0.9 0.08 0.04 0.03 0.09 JUN 03... 150 146 648 0.90 0.16 0.21 1.4 0.19 0.19 0.11 0.34 AUG 11... 223 240 39.5 0.32 0.08 0.10 0.8 0.18 0.09 0.06 0.18 K = non-ideal count 128 PIG DE LA PLATA BASIN 50046000 RIO DE LA PLATA AT TOA ALTA, PR--Continued (National stream-quality accounting network station) WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 ALUM- BERYL- CHRO- INUM, ARSENIC BARIUM, LIUM, CADMIUM MIUM, COBALT, COPPER, IRON, LEAD, DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS AL) AS AS) AS BA) AS BE) AS CD) AS CR) AS CO) AS CU) AS FE) AS PB) OCT 1986 16... 20 3 54 <0.5 2 <1 <3 6 13 -5 DEC 26... - FEB 1987 13... 120 1 43 <0.5 <1 <1 <3 8 110 <5 APR 29... JUN 03... 80 <1 34 1 <1 2 <3 6 71 <5 AUG 11... MANGA- MOLYB- SELF- STRON- VANA- LITHIUM NESE, MERCURY DENUM, NICKEL, NIUM, SILVER, TIUM, D1UM, ZINC, DIS- DIS- DIS- DIS- DIS- DIS- 01S- DIS- DIS- DIS- SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS LI) AS MN) AS HG) AS MO) AS HI) AS SE) AS AG) AS SR) AS V) AS Z'.) OCT 1986 16... 6 110 <0.1 <10 1 <1 <1 270 7 6 DEC 26... -- -- FEB 1987 13... 5 36 0.4 <10 2 <1 <1 130 <6 15 APR 29... JUN 03... 6 5 0.2 <10 <1 <1 <1 99 8 8 AUG PESTICIDE ANALYSES CHLOR- DI- DI- ENDO- PCB, ALDRIN, DANE, DDD, ODE, DDT, AZINON, ELDRIN SULFAN, DATE TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 03... 1345 <0.1 <0.01 <0.1 <0.01 <0.01 <0.01 0.02 <0.01 <0.01 HEPTA- METH- METHYL METHYL HEPTA- CHLOR MALA- OXY- PARA- TRI- ENDRIN, ETHION, CHLOR, EPDXIDE LINDANE THION, CHLOR, THION, THION, MIREX, DATE TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 03... <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 NAPH- THA- LENES, PAPA- POLY- PER- 1.0X- TOTAL THION, CHLOR. THANE APHENE, TRI- 2,44, 2,4,5-T 2, 4-DP SILVEX, DATE TOTAL TOTAL TOTAL TOTAL THION TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 03... <0.01 <0.1 <0.1 <1 <0.01 0.01 <0.01 <0.01 <0.01 129 RIO DE LA PLATA BASIN 50046000 RIO DE LA PLATA AT TOA ALTA, PR--Continued (National stream-quality accounting network station) WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT SED. SEDI- SUSP. MENT, SIEVE STREAM- SEDI- DIS- DIAM. FLOW, MENT, CHARGE, PERCENT INSTAN- SUS- SUS- FINER DATE TIME TANEOUS PENDED PENDED THAN (CFS) (MG/L) (T/DAY) .062 MM OCT 1986 16... 1250 26 13 0.91 40 DEC 26... 1020 44 43 5.1 71 FEB 1987 13... 1135 376 124 126 93 APR 29... 1040 55 107 16 90 JUN 03... 1345 1600 87 376 76 130 RIO DE LA PLATA aAsim 50046900 RIO DE LA PLATA AT HIGHWAY 2 NEAR TOA ALTA, PR LOCATION.--Lat 18°24'41', long 66°15'39', Hydrologic Unit 21010005, on left bank, at downstream side of bridge on Highway 2, 1.3 mi ( 2.1 km) downstream from Rio Lajas, and 1.6 mi (2.6 km) northwest of Toa Alta, 11.3 mi (18.2 km) downstream from Puerto Rico Aqueduct and Sewer Authority reservoir. Prior to September 25, 1984, at site about 1.0 mi (1.6 km) upstream. DRAINAGE AREA.--208 m1 2 (539 km 2), excludes 8.2 m1 2 (21.2 km 2) upstream from Lago Carite, flow from which is diverted to Rio Guamani. Area at site used prior to September 25, 1984, 200 mi 2 (518 km 2 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--November 1959 (measurement only), January 1960 to current year. Prior to September 1984, published as Rio de la Plata at Toa Alta, P.R. GAGE.--Water-stage recorder. Elevation of gage is 0.0 ft (0.0 m), from topographic map. REMARKS.--Records fair. National Weather Service gage-height telemeter at station. Regulation at all stages by Puerto Rico Aqueduct and Sewer Authority reservoir upstream from gage. AVERAGE DISCHARGE.--27 years (1961-87), 280 ft'is (7.930 0/s), 19.12 in/yr (486 mm/yr), 202,900 acre-ft/yr (250 hm'/yr); median of yearly mean discharges, 237 ft'/s (6.71 e/s), 172,000 acre-ft/yr (210 hmgyr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 95,500 ft'is (2,700 m 3 /s), Sept. 6, 1960, gage height, 36.35 ft (11.079 m), from floodmark, from rating curve extended above 12,000 ft'/s (340 mi/s) on basis of contracted-opening measurement of peak flow at site 1.0 mi upstream and different datum; minimum discharge, 2.2 ft3/s (0.062 m'/s), Apr. 25. 1984. EXTREMES OUTSIDE PERIOD OF RECORD.--Approximate discharges and elevations of major floods, as pointed out by local residents are as follows: Sept. 13, 1928, 120,000 ft'is (3,400 0/s), gage height, 37.4 ft (11.40 m); June 16, 1943. 82.000 ft'/s (2,320 e/s), gage height, 34.4 ft (10.48 m), at site 1.0 mi upstream and different datum. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 6,000 ft'is (170 10/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft'/s) (m 3/s) (ft) (m) Date Time (f't/s) (m 3/s) (ft) (m) Apr. 12 0015 *19,200 544 *18.54 5.651 May 21 1230 8,480 240 14.50 4.420 Minimum discharge, 14 ft'is (0.396 0/s), Mar. 11-13. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 16 93 305 33 136 46 19 53 1130 223 81 110 2 15 108 160 31 107 38 19 53 1390 148 93 141 3 16 88 110 28 73 29 21 95 1770 168 438 93 4 21 96 95 27 51 22 22 99 1180 159 317 71 5 24 86 80 27 40 19 24 63 529 361 352 51 6 23 114 78 26 34 17 26 58 369 297 211 40 7 22 150 74 28 32 17 596 51 278 279 145 31 8 27 390 70 32 29 15 211 72 218 266 96 31 9 44 271 90 77 27 15 79 148 198 177 111 32 10 41 286 87 98 220 15 38 412 195 159 75 26 11 20 259 79 68 1170 15 1540 351 168 129 56 23 12 31 1670 132 48 1960 15 9060 583 145 113 46 48 13 26 2290 169 40 383 14 3730 325 162 96 48 32 14 24 626 215 37 472 15 1360 182 132 87 44 22 15 29 402 254 59 320 56 1590 105 278 95 51 25 16 30 369 146 44 178 80 1140 75 215 110 52 23 17 19 518 129 39 113 720 624 60 206 109 66 24 18 17 1570 108 36 85 312 352 102 197 126 50 23 19 43 949 87 33 66 130 232 1000 199 110 68 25 20 181 692 71 32 57 76 177 1440 226 112 62 205 21 181 276 61 33 48 73 140 3400 631 109 49 193 22 45 168 53 32 44 54 118 1830 3050 102 36 72 23 44 156 49 31 42 33 100 1170 1080 122 28 47 24 71 124 43 28 39 31 89 534 477 89 25 31 25 42 112 49 26 38 31 75 1500 301 78 24 25 26 32 169 45 25 42 28 67 2050 223 107 165 22 27 332 125 43 25 66 32 61 905 179 99 61 18 28 217 109 41 25 57 28 58 517 172 124 42 17 29 181 184 40 24 --- 23 54 364 233 101 33 24 30 133 410 37 56 22 53 461 184 91 29 36 31 78 --- 34 74 20 --- 859 --- 90 211 --- TOTAL 2025 12860 3034 1222 5929 2041 21675 18917 15715 4436 3165 1561 MEAN 65.3 429 97.9 39.4 212 65.8 722 610 524 143 102 52.0 MAX 332 2290 305 98 1960 720 9060 3400 3050 361 438 205 MIN 15 86 34 24 27 14 19 51 132 78 24 17 AC-FT 4020 25510 6020 2420 11760 4050 42990 37520 31170 8800 6280 3100 CFSM .33 2.14 .49 .20 1.06 .33 3.61 3.05 2.62 .72 .51 .26 IN. .38 2.39 .56 .23 1.10 .38 4.03 3.52 2.92 .83 .59 .29 CAL YR 1986 TOTAL 81868.8 MEAN 224 MAX 12000 MIN 3.0 AC-FT 162400 CFSM 1.12 IN. 15.23 WTR YR 1987 TOTAL 92580 MEAN 254 MAX 9060 MIN 14 AC-FT 183600 CFSM 1.27 IN. 17.22 131 ATLANTIC A Ai Drainage boundaries Mdeterminate .218 4753QN— CAMITIO V0499920 •••-•, in limestone terrone a cc 02198?)11r 1.:,;./;\\ ose""--,f 0119 0491 11221' Limestone Igneous and sedimentary rocks 4852110 il 10490 ,.' 290 / A Reaves, ae g_r'' / • , Rie Piedras C \. / i1 , 0488‘ •-, 1. ,' , ,....,, t ORO TisiLiJILLO ALTO M Las Curios „Drainage tioundary Drainage boundark . AGUAS BUENOS Rio de in Pinto basin cr"" Co Grond 50.1 / / ....Logo de Cidro CIDRA '• EXPLANATION QUALITY—OF WATER STATION V0476 AND NUMBER 0220 WELL AND WELL NUMBER A°490 CREST—STAGE GAGE AND NUMBER —Map area "."," FAJARDO' 5 KILOMETEFiS mAYASVEZ 1 0 C-1. P1)*CC Figure 17.--Rio Hondo to Rio Puerto Nuevo basins. 132 RIO HONDO BASIN 50047530 RIO HONDO AT FLOOD CHANNEL NEAR CATANO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°2613", long 66°0936", 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.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 20... 0920 6200 7.50 27.0 10 0.3 4 159 54000 11000 DEC 30... 0915 13500 7.30 26.0 5.1 0.5 6 300 K640000 93000 FEB 1987 25... 1315 21000 7.90 30.5 5.3 9.8 141 210 K750000 K8200 APR 23... 0905 23000 8.30 28.5 3.5 6.8 95 220 K1400000 60000 JUN 25... 0835 8800 7.70 28.5 2.2 2.2 29 47 K1200000 30000 AUG 27... 1145 2390 7.70 31.5 26 6.6 91 18 27000 K2000 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT 01S- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED T1ON SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 20... 700 569 66 129 1099 17 41 127 <0.5 290 2100 DEC 30... 189 4700 FEB 1987 25... 170 390 APR 23... 2500 2400 190 500 4500 39 170 160 <0.5 1200 8400 JUN 25... 180 2d00 AUG 27... 260 180 38 39 330 9 18 77 -- 97 700 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 20... 0.2 10 3800 24 0.09 0.01 -0.10 4.40 2.6 DEC 30... 18 0.08 0.02 <0.10 8.90 6.1 FEB 1987 25... 11 0.06 0.04 <0.10 6.60 5.4 APR 23... 0.5 5.4 15100 25 0.06 0.04 1.0 2.80 36 JUN 25... 24 0.15 0.05 0.20 4.20 4.9 AUG 27... 0.2 9.2 1280 33 0.35 0.05 0.40 0.70 0.7 K non-ideal count E = estimate 133 RIO HONDO BASIN 50047530 RIO HONDO AT FLOOD CHANNEL NEAR CATANO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA t NITRO NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 20... 7.0 1.70 9 100 500 1 1 10 DEC 30... 15 2.20 -- - FEB 1987 25... 12 2.00 APR 23... 40 41 1.40 2 100 1700 1 17 50 JUN 25... 9.1 9.3 41 0.04 AUG 27... 1.4 1.8 8.0 0.29 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELL- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB, DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) NOV 1986 20... 780 <5 380 0.1 <1 <1 20 ,0.01 8 0.34 DEC 30... FEB 1987 25... APR 23... 590 .5 570 0.2 <1 <1 30 <0.01 9 0.77 JUN 25... AUG 27... 1-34 RIO DE BAYAMON BASIN 50047600 RIO DE BAYAMON NEAR AGUAS BUENAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18-1439, long 66°0839", at bridge on Highway 156, and 2.9 mi (4.7 km) west of Aguas Buenas plaza. DRAINAGE AREA.--18.5 sq mi (47.9 sq km). PERIOD OF RECORD.--Water years 1958-65, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COL1- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIF1C SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 20... 1600 24 267 8.20 27.0 6.0 7.7 100 100 K100 230 DEC 16... 1540 20 301 7.90 22.5 7.9 8.6 102 10 K700 K1200 FEB 1987 10... 1350 26 279 8.20 23.0 2.6 8.3 100 <10 K64 560 APR 30... 0930 28 270 7.80 24.0 8.0 98 K80 250 JUN 02... 1240 19 277 8.40 27.5 4.2 8.0 105 <10 490 3100 AUG 12... 1400 35 235 8.00 26.0 7.9 101 230 660 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- 01S- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 20... 80 0 18 8.6 15 0.7 2.9 89 <0.5 10 16 DEC 16.., 100 FEB 1987 10... 98 APR 30... 94 0 22 9.6 16 0.7 2.5 94 <0.5 11 23 JUN 02... - 100 AUG 12... 82 0 19 8.5 17 0.8 2.1 89 11 15 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEN, DEN, GEM, DEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/1 (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 20... 0.1 22 146 9.46 8 0.29 0.01 0.30 0.02 0.28 DEC 16... 17 -- <0.01 0.70 <0.01 0.59 FEB 19E37 10... - 3 - <0.01 0.40 <0.01 0.39 APR 30... 0.1 22 160 12.1 2 -- <0.01 0.20 <0.01 0.49 JUN 02... 6 0.59 0.01 0.60 0.02 1.2 AUG 12... 0.1 22 147 13.9 4 0.48 0.02 0.50 0.01 0.29 K non-ideal count 135 RIO DE BAYAMON BASIN 50047600 RIO DE BAYAMON NEAR AGUAS BUENAS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 CHRO- GEN,AM- BARIUM, BORON, CADMIUM M1UM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC DEN, DEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NITRO- OCT 1986 20... 0.3 0.6 0.05 1 ,100 <10 <1 10 10 DEC 16... 0.6 1.3 5.8 0.05 FEB 1987 10... 0.4 0.8 3.5 0.03 APR 30... 0.5 0.7 3.1 0.03 1 <100 30 2 5 10 JUN 02... 0.2 0.8 0.05 AUG 12... 0.3 0.8 3.5 0.09 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) OCT 1986 20... 870 <5 80 <0.1 <1 1 130 <0.01 1 0.04 DEC 16... FEB 1987 10... APR 30... 370 6 30 <0.1 <1 1 10 <0.01 3 0.03 JUN 02... AUG 12... RIO DE BAYAMON BASIN 136 50047990 RIO GUAYNABO NEAR BAYAMON, PR WATER-QUALITY RECORDS LOCATION.--Lat 182232, long 660759, at bridge on Highway 833, 0.2 mi (0.3 km) upstream from Rio de Bayamon, and 2.3 mi (3.7 km) southeast of Bayamon plaza. DRAINAGE AREA.--73.2 sq mi (189.6 sq km). PERIOD OF RECORD.--Water years 1958, 1964, 1971-73, 1976, 197 9 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIF1C SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- 1CAL 0.7 KF AGAR 1NSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 28... 1110 50 353 7.00 25.0 44 7.0 85 33 K7600 3600 DEC 22... 1440 26 488 7.50 26.5 74 3.8 48 28 K83000 5700 FEB 1987 23... 1235 19 515 7.50 25.5 0.7 5.5 68 19 4200 K300 APR 29.., 1345 20 437 7.50 30.0 1.1 8.5 113 10 2900 K200 JUN 16... 1305 71 380 7.90 28.5 72 6.0 77 19 K200000 55000 AUG 19... 0905 22 410 7.30 27.5 2.4 4.2 53 20 K95000 9300 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- D1S- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 28... 130 7 35 9.5 22 0.9 4.5 120 <0.5 17 24 DEC 22... -- -- 160 -- FEB 1987 23... _ 170 _ APR 29... 160 0 44 13 26 0.9 3.5 150 <0.5 15 35 JUN 16... - 140 AUG 19... 150 1 39 13 25 0.9 3.5 150 13 28 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEM, GEM, GEN, GEN. DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) 5102) (M6/1) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 28... 0.1 22 206 27.8 93 0.93 0.07 1.00 1.40 1.5 DEC 22... - -- 58 0.27 0.03 0.30 3.10 0.8 FEB 1987 23... - 19 0.07 0.03 0.10 2.70 0.6 APR 29... 0.2 26 250 13.5 4 0.46 0.04 0.50 0.09 1.1 JUN 16... -- 138 0.54 0.06 0.60 0.68 1.0 AUG 19... 0.2 31 240 14.3 5 0.24 0.06 0.30 1.00 1.0 K = non-ideal count 137 RIO DE BAYAMON BASIN 50047990 RIO GUAYNABO NEAR BAYAMON, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA NITRO- NITRO- PHOS- NITRO- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 <1 1 20 28... 2.9 3.9 17 0.24 1 100 <10 DEC 22... 3.9 4.2 19 0.07 - FEB 1987 23... 3.3 3.4 15 0.89 APR 29... 1.2 1.7 7.5 0.16 1 100 30 1 5 10 JUN 16... 1.7 2.3 10 0.31 -- - AUG 19... 2.0 2.3 0.51 -- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) MANGA- OCT 1986 28... 3800 5 300 0.3 ,1 <1 40 -0.01 2 0.05 DEC 22... -- FEB 1987 23... APR 29... 180 5 220 0.1 <1 10 <1 <0.01 6 0.06 JUN 16... - AUG 138 RIO DE BAYAMON BASIN 50048510 RIO DE BAYAMON AT FLOOD CHANNEL AT BAYAMON, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°24'29", long 66°09'04", at bridge on Highway 890, 1.0 (1.6 km) downstream from bridge on High­ way 2, and 3.2 si (5.1 km) above mouth. DRAINAGE AREA.--71.9 sq ml (186.2 sq km). PERIOD OF RECORD.--Water years 1974 to current year. REMARKS.--Prior to 1979 sampling site was 0.8 mile (1.3 km) downstream but was changed because of flood channel construction. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN. OXYGEN COL1- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM. FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 28... 0815 350 342 7.20 24.0 72 6.2 74 67 45000 28000 DEC 19... 0815 E100 478 7.10 23.0 27 4.3 50 18 23000 3900 FEB 1987 17... 1425 56 460 7.30 28.5 8.2 3.9 50 20 54000 2600 APR 27... 1505 55 419 7.70 31.5 1.5 10.8 147 16 21000 K100 JUN 05... 1140 E150 367 7.60 28.0 130 5.0 64 <10 K170000 6400 AUG 10... 1330 56 381 7.50 31.5 14 7.7 106 15 51000 K1500 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SLUM, SODIUM, AD- SIUM, NAT WH SULFATE RIDE, TOTAL WH MAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE 01S- D1S- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) OCT 1986 28... 110 3 30 9.1 17 0.7 4.0 110 .0.5 18 18 DEC 19... 160 FEB 1987 17... 150 APR 27... 160 0 42 13 24 0.9 2.7 160 <0.5 22 40 JUN 05... 130 AUG 10... 150 8 38 13 23 0.8 2.6 140 17 24 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEM, GEM, GEM, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+1103 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) 5IO2) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 28... 0.1 21 183 173 180 0.36 0.14 0.50 0.56 1.2 DEC 19... 59 0.44 0.16 0.60 1.40 0.7 FEB 1987 17... 26 0.41 0.09 0.50 1.00 1.2 APR 27... 0.2 25 265 39.0 4 0.34 0.06 0.40 0.01 1.1 JUN 05... 236 0.74 0.06 0.80 0.11 0.3 AUG 10... 0.2 27 230 34.8 1 0.41 0.09 0.50 0.24 1.1 K = non-ideal count E = estimate 139 RIO DE BAYAMON BASIN 50048510 RIO DE BAYAMON AT FLOOD CHANNEL AT BAYAMON, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MON1A 4. NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS RA) AS B) AS CD) AS CR) AS CU) OCT 1986 28.., 1.8 2.3 0.32 1 100 <10 1 <1 20 DEC 19... 2.1 2.7 12 0.26 FEB 1987 17... 2.2 2.7 12 0.44 APR 27... 1.1 1.5 6.6 0.13 1 100 30 <1 13 20 JUN OS... 0.4 1.2 0.16 AUG 10... 1.3 1.8 0.37 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS NN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) OCT 1986 28... 5900 5 330 0.2 .1 <1 40 <0.01 4 0.04 DEC 19... FEB 1987 17... APR 27... 250 <5 190 1.7 <1 <1 <10 <0.01 7 0.05 JUN OS... AUG 10... PESTICIDE ANALYSES CHLOR- DI- DI- ENDO- PCB, ALORIN, DANE. DOD, ODE, DDT, AZINON, ELDR1N SULFAN, DATE TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN OS... 1140 <0.1 <0.01 <0.1 <0.01 <0.01 <0.01 0.04 <0.01 <0.01 HEPTA- METH- METHYL METHYL HEPTA- CHLOR MALA- OXY- PARA- TRI- ENDRIN, ETHION, CHLOR, EPDXIDE LINDANE THION, CHLOR, THION, THIGH, MIREX, DATE TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN <0.01 <0.01 <0.01 <0.01 <0.01 0.02 <0.01 <0.01 <0.01 <0.01 NAPH- THA- LENES, PARA- POLY- PER- TOX- TOTAL THION, CHLOR. THANE APHENE, TRI- 2,4-0, 2,4,5-1 2, 4-DP SILVEX, DATE TOTAL TOTAL TOTAL TOTAL THION TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN OS... <0.01 <0.1 <0.1 <1 <0.01 0.01 <0.01 <0.01 <0.01 140 RIO PUERTO NUEVO BASIN 50048800 RIO PIEDRAS NEAR RIO PIEDRAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°2215", long 66°0340, at bridge on Winston Churchill Avenue in the El Senorial Housing area, 0.5 mi (0.8 km) west of Highway 176, and 2.5 mi (4.0 km) southwest of Rio Piedras plaza. DRAINAGE AREA.--8.17 sq mi (20.9 sq km). PERIOD OF RECORD.--Water years 1972 to current year. WATER QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER !TY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 03... 0915 7.9 418 7.45 25.0 2.5 6.2 76 89 K60000 K330000 DEC 08... 0945 10 420 7.45 23.0 7.1 83 K250000 K260000 FEB 1987 19... 1005 5.6 392 7.25 22.0 7.3 84 <10 K71000 25000 APR 06... 0910 5.7 359 7.40 24.0 15 5.5 66 25 K1100000 K130000 JUN 10... 0825 16 316 7.80 25.0 21 7.2 10 46000 67000 AUG 11... 1045 13 352 8.00 27.5 I 6.4 13 26000 42000 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 03... 140 0 36 12 27 1 4.3 150 <0.5 20 28 DEC 08... - 151 FEB 1987 19... - 140 APR 06... 140 5 36 11 25 1 4.0 130 <0.5 16 24 JUN 10... 120 AUG 11... 120 0 30 10 22 0.9 2.6 120 12 23 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEM, GEM, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2-0403 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 03... 0.1 30 247 5.29 9 0.62 0.08 0.70 5.00 2.4 DEC 08... 0.84 0.06 0.90 3.70 1.2 FEB 1987 19... 0.76 0.04 0.80 0.47 0.33 APR 06... 0.2 31 225 3.59 34 0.68 0.12 0.80 1.20 1.6 JUN 10... 5 0.78 0.02 0.80 0.34 1.3 AUG 11... 0.2 29 200 8.64 31 , 48 0.02 0.50 0.15 0.95 K non-ideal count 141 RIO PUERTO NUEVO BASIN 50048800 RIO PIEDRAS NEAR RIO PIEDRAS, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 03... 7.4 8.1 36 0.96 1 100 <10 <1 <1 <10 DEC 08... 4.9 5.8 26 0.87 FEB 1987 19... 0.8 1.6 1.0 APR 06... 2.8 3.6 16 0.56 2 100 10 <1 4 20 JUN 10... 1.6 2.4 0.18 -- AUG 11... 1.1 1.6 7.1 0.28 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) NOV 1986 03... 510 <5 200 0.2 <1 <1 40 <0.01 6 0.16 DEC 08... FEB 1987 19... APR 06... 1000 <5 220 <0.1 <1 <1 20 <0.01 6 0.07 JUN 10... AUG 11... PESTICIDE ANALYSES CHLOR- DI- DI- ENDO- PCB, ALDRIN, DANE, ODD, ODE, DDT, AZINON, ELDRIN SULFAN, DATE TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1987 10... 0915 <0.1 <0.01 <0.1 <0.01 <0.01 <0.01 0.01 <0.01 <0.01 HEPTA- METH- METHYL METHYL HEPTA- CHLOR MALA- OXY- PAM- TRI- ENDRIN, ETH1ON, CHLOR, EPDXIDE LINDANE THION, CHLOR, TH1ON, THION, MIREX, DATE TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1987 10... <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 NAPH- THA- LENES, PAM- POLY- PER- TOX- TOTAL THION, CHLOR. THANE APHENE, TRI- 2,4-D, 2,4,5-T 2, 4-DP SILVEX, DATE TOTAL TOTAL TOTAL TOTAL THION TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (LG/L) (UG/L) (UG/L) JUN 1987 10... <0.01 <0.1 <0.1 <1 <0.01 <0.01 <0.01 <0.01 <0.01 RIO PUERTO NUEVO BASIN 142 50049100 RIO P1EDRAS AT HATO REV, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°24'34", long 66°0410", at bridge on Avenida Piniero at Expreso Las Americas, and 0.8 mi (1.3 km) southwest of Hato Rey. DRAINAGE AREA.--15.4 sq mi (39.9 sq km). PERIOD OF RECORD.--Water years 1971 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIF1C SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER 1TY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 03... 1145 16 395 7.55 27.5 1.8 5.4 69 34 38000 8100 DEC 08... 1240 29 306 7.25 27.0 4.9 62 240000 98000 FEB 1987 19... 1305 12 480 7.25 26.0 17 5.6 69 16 K110000 24000 APR 06... 1245 5.7 381 7.50 29.0 22 5.2 68 36 470000 7200 JUN 10... 1210 35 359 7.80 29.0 9.9 6.6 18 320000 K190000 AUG 11... 1330 24 423 7.90 30.0 3.1 5.0 14 220000 K110000 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 03... 140 0 41 10 26 1 3.6 150 <0.5 17 25 DEC 08... 112 FEB 1987 19... 150 APR 06... 140 0 39 9.4 25 1 3.8 140 <0.5 19 24 JUN 10... 140 AUG 11... 140 0 37 11 28 1 3.4 140 11 30 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 03... 0.1 27 239 10.4 11 0.79 0.21 1.00 0.67 1.1 DEC 08... 0.79 0.01 0.80 0.02 0.48 FEB 1987 19... -- 36 1.21 0.29 1.50 1.10 1.1 APR 06... 0.2 26 230 3.54 50 0.59 0.11 0.70 1.10 1.5 JUN 10... -- 1 0.52 0.08 0.60 1.50 1.4 AUG 11... 0.2 31 240 15.6 11 0.80 0.10 0.90 0.59 1.3 K non-ideal count 143 RIO PUERTO NUEVO BASIN 50049100 RIO PIEDRAS AT NATO REV, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 03... 1.8 2.8 12 0.33 2 100 <10 <1 <1 <10 DEC 08... 0.5 1.3 5.8 0.04 FEB 1987 19... 2.2 3.7 16 0.54 APR <1 06... 2.6 3.3 15 0.63 2 100 30 <1 20 JUN 10... 1.6 2.2 0.57 AUG 11... 1.9 2.8 12 0.58 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS P8) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) NOV 1986 03... 650 <5 240 0.1 <1 <1 30 <0.01 ,1 0.09 DEC 08... FEB 1987 19... APR 06... 1600 <5 230 <0.1 <1 <1 20 <0.01 6 0.15 JUN 10... AUG 11... 144 RIO PUERTO NUEVO BASIN 50049820 LAGUNA SAN JOSE NO. 2 AT SAN JUAN, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°25'46, long 6602'10, 0.2 mi (0.3 km) east of Cant) de Martin Pena, and 650 ft (200 m) south of Isla Guachinango. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 DEPTH OXYGEN, COLI- STREP- ALKA- AT SPE- TRANS- DIS- FORM, TOCOCCI UNITY SAMPLE CIFIC PAR- SOLVED FECAL, FECAL, WAT WH LOC- CON- PH TEMPER- ENCY OXYGEN, (PER- 0.7 KF AGAR TOT FET ATION, DUCT- (STAND- ATURE (SECCH1 DIS- CENT UM-MF (COLS. FIELD DATE TIME TOTAL ANCE ARD WATER DISK) SOLVED SATUR- (COLS./ PER MG/L AS (FEET) (US/CM) UNITS) (DEG C) (IN) (MG/L) ATION) 100 ML) 100 ML) CAC03 NOV 1986 18... 1005 1.00 14000 8.55 27.5 16.0 5.5 73 60000 23000 132 DEC 31... 0830 1.00 16000 9.05 26.5 19.0 4.4 58 K81000 12000 127 FEB 1987 25... 0910 1.00 25000 8.40 26.0 13.8 1.2 16 K93000 K14000 160 APR 30... 0920 1.00 13800 9.00 29.5 23.0 5.7 78 K8200 K1000 130 JUN 25... 1030 1.00 11000 9.00 29.5 19.9 8.4 114 K7700 K10000 100 AUG 27... 0730 1.00 25000 8.70 29.5 18.0 3.6 51 K1300 K500 140 SOLIDS, RESIDUE NITRO- TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA NITRO- PHOS- CARBON, DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN PHOROUS ORGANIC SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L) AS N) AS N) ASH) AS N) AS N) AS N) AS N) ASP) AS C) NOV 1986 18... 6 0.09 0.01 0.10 0.22 2.2 2.4 2.5 0.57 16 DEC 31... 28 <0.01 0.10 0.12 2.4 2.5 2.6 0.53 18 FEB 1987 25... 11 <0.01 0.10 1.20 2.5 3.7 3.8 0.70 13 APR 30... 9 <0.01 0.10 0.05 2.4 2.4 2.5 0.31 11 JUN 25... 41 0.07 0.03 0.10 0.11 1.8 1.7 1.8 0.26 13 AUG 27... 16 <0.01 0.10 0.05 1.7 1.8 1.9 0.40 16 K = non-ideal count 145 RIO PUERTO NUEVO BASIN 50049920 BAHIA DE SAN JUAN NO. 5 AT SAN JUAN, PR WATER-QUALITY RECORDS LOCATION--Lat 18°2637, long 66-05'11, 0.4 ml (0.6 km) west of Puente de la Constitucion, and 0.5 ml (0.8 km) south from U.S. Naval Reservation. DRAINAGE--Indeterminate. PERIOD OF RECORD--Water years 1974 to present. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 DEPTH OXYGEN, COLI- STREP- ALKA­ AT SPE- TRANS- DIS- FORM, TOCOCCI LINITY SAMPLE C1FIC PAR- SOLVED FECAL, FECAL, WAT WH LOC- CON- PH TEMPER- ENCY OXYGEN, (PER- 0.7 KF AGAR TOT FET ATION, DUCT- (STAND- ATURE (SECCHI DIS- CENT UM-MF (COLS. FIELD DATE TIME TOTAL ANCE ARD WATER DISK) SOLVED SATUR- (COLS./ PER MG/L AS (FEET) (US/CM) UNITS) (DEG C) (IN) (MG/L) ATION) 100 ML) 100 ML) CAC03 NOV 1986 18... 1135 1.00 10000 7.90 29.0 53.0 5.8 78 K12000 K730 133 DEC 31... 1000 1.00 47000 7.95 27.0 41.5 3.7 55 K182000 59000 120 FEB 1987 25... 1035 1.00 33000 7.90 27.5 36.0 0.2 3 K1500000 55000 130 APR 30... 1200 1.00 42000 7.90 29.5 29.0 2.2 34 K860000 K12000 140 JUN 25... 1230 1.00 31000 7.50 30.0 20.8 1.6 23 210000 K11000 140 AUG 27... 1000 1.00 32000 7.80 30.5 23.4 1.8 27 45000 2300 120 RESIDUE NITRO- TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- AT 105 GEN, GEN, GEM, GEN, GEM, MON1A + NITRO- NITRO- PHOS- CARBON, DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEN, PHOROUS ORGANIC SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) AS P) AS C) NOV 1986 18... 5 0.06 0.04 0.10 1.00 0.90 1.9 2.0 0.28 4.8 DEC 31... 12 0.09 0.01 0.10 0.64 0.06 0.7 0.8 0.08 2.4 FEB 1987 25... 6 0.09 0.01 0.10 1.20 2.0 3.2 3.3 0.30 5.2 APR 30... 10 0.07 0.03 0.10 1.70 3.2 3.3 0.31 1.5 3.1 JUN 25... 151 0.23 0.07 0.30 2.20 0.60 2.8 3.1 14 0.41 2.0 AUG 27... 10 0.16 0.04 0.20 0.78 0.32 1.1 1.3 5.8 0.14 4.7 K non-ideal count 146 THIS PAGE WAS LEFT BLANK INTENTIONALLY 147 SAN JUAN ATLANTIC OCEAN LOIZA ALDEA Logona San Jose 22 503 Coastal basin ) Coostal basin t„..., \O CAROLINA RIO GRANDE 0 S C AN OVA NA TRUJI LOALTO Rib Herrero basin Pb P tetlf100 450 0.1 <1 1 60 <0.01 7 0.05 DEC 18... FEB 1987 11... APR 28... 2600 5 140 0.1 <1 1 10 <0.01 3 0.01 JUN 22... AUG 18... 212 RIO CHICO BASIN 50091800 RIO CHICO AT PROVIDENCIA, PR WATER-QUALITY RECORDS LOCATION.--Lat 17°5916, long 66°00'18", at flat low bridge 200 ft (61 m) south of Highway 3, 0.5 ml (0.8 km) above mouth, and 1.5 ml (2.4 km) southeast of Patillas plaza. DRAINAGE AREA.--4.9 sq mi (12.8 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARO WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1986 30... 1250 6.0 342 7.50 27.0 1.6 6.2 78 45 480000 48000 DEC 24... 0930 3.0 420 7.40 22.5 2.8 2.4 28 41 420000 31000 FEB 1987 09... 1205 0.82 667 7.20 28.0 16 1.0 o 120 2900000 380000 APR 20... 1105 0.81 618 7.10 28.0 3.0 0.9 12 38 K86000 K140000 JUN 12... 0925 0.47 736 7.20 29.0 100 0.0 0 110 2800000 69000 AUG 24... 0835 0.47 819 7.50 30.0 2.3 0.0 0 160 K7900000 660000 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- 01S- (MG/L TOT FLO SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS 504) AS CL) OCT 1986 30... 96 0 22 10 31 1 2.2 116 <0.5 16 25 DEC 24... 154 - FEB 1987 09... 220 APR 20... 160 0 39 15 58 2 4.4 220 <0.5 19 49 JUN 12... 230 AUG 24... 150 0 34 15 67 2 10 250 40 71 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO20403 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 1986 30... 0.2 32 208 3.36 2 0.39 0.01 0.40 2.00 0.6 DEC 24... - 10 0.18 0.02 0.20 4.20 1.3 FEB 1987 09... 22 0.07 0.03 0.10 20.0 10 APR 20... 0.3 32 349 0.75 <1 0.09 0.01 0.10 9.90 0.1 JUN 12... 167 0.07 0.03 0.10 20.0 2.0 AUG 24... 0.2 33 420 0.45 34 0.07 0.03 0.10 26.0 24 K = non-ideal count 213 RIO CHICO BASIN 50091800 RIO CHICO AT PROVIDENCIA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GIN, GIN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) OCT 1986 30... 2.6 3.0 13 0.48 <1 <100 <10 <1 <1 10 DEC 24... 5.5 5.7 25 0.95 FEB 1987 09... 30 30 4.40 APR 20... 10 10 0.41 <1 100 50 <1 3 20 JUN 12... 22 22 13.0 AUG 24... 50 50 11.0 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) OCT 1986 30... 440 <5 70 <0.1 <1 <1 30 <0.01 5 0.06 DEC 24... FEB 1987 09... APR 20... 2400 <5 740 0.2 <1 <1 <10 <0.01 10 1.6 JUN 12... AUG 24... RIO GRANDE DE PATILLAS BASIN 214 50092000 RIO GRANDE DE PATILLAS NEAR PATILLAS, PR LOCATION.--Lat 18°02'04", long 66°01'58". Hydrologic Unit 21010004, on left bank, at foot bridge. off Highway 184, 1.2 mi (1.9 km) upstream from Lago Patillas Dam and 2.2 mi (3.5 km) northwest of Patillas. DRAINAGE AREA.--18.3 mi (47.4 km 2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February 1959 to October 1965 (annual low-flow and occasional measurements only), January 1966 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 235 ft (72 m), from topographic map. REMARKS.--Records fair. National Weather Service gage-height telemeter at station. AVERAGE DISCHARGE.--21 years (1967-87), 59.9 ft'is (1.696 m,/s), 44.45 in/yr (1,129 mm/yr), 43,400 acre-ft/yr (53.5 hma/yr); median of yearly mean discharges. 61 ft'is (1.73 e/s), 44,200 acre-ft/yr (54 h0/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 14,800 ft'is (419 m'/s). Sept. 16, 1975, gage height, 12.45 ft (3.795 m), from rating curve extended above 250 ft'is (7.08 e/s) on basis of slope-area measurement of peak flow; minimum discharge, 4.6 ft'/s (0.130 e/s), May 13-16, 1968. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 2,500 ft'is (70.8 e/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft'/s) (m 3/s) (ft) (m) Date Time (ft'/s) (m 3/s) (ft) (m) Nov. 12 1600 2,510 71.1 8.51 2.594 June 21 1730 *3,700 105 *9.54 2.908 Minimum discharge, 8.3 ft'is (0.235 613/s), Apr. 2, 3, 11. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 18 22 36 27 37 15 10 14 21 50 44 27 2 17 27 34 25 28 16 8.5 17 18 53 28 37 3 16 21 78 24 24 20 10 18 33 57 78 41 4 16 21 55 25 21 29 11 31 24 120 83 24 5 15 35 68 39 21 37 13 21 18 122 145 20 6 16 28 45 55 21 24 50 52 17 62 67 17 7 18 96 93 131 20 21 32 21 21 50 45 16 a 17 164 57 50 20 18 17 16 17 45 35 16 9 25 84 56 38 19 17 15 13 18 39 35 21 10 28 57 69 33 18 16 13 13 20 52 31 29 11 19 88 151 31 37 17 12 12 18 44 28 25 12 16 854 89 28 23 21 107 26 18 35 25 21 13 16 277 68 26 31 15 93 15 21 31 24 18 14 16 147 61 26 40 14 110 12 17 31 22 15 15 16 132 50 33 40 15 41 11 43 46 22 15 16 40 252 46 28 24 18 27 10 62 35 28 15 17 26 190 45 25 21 17 27 10 29 29 24 16 18 20 117 42 24 21 18 21 9.7 38 26 21 83 19 16 82 39 23 19 14 20 133 123 25 23 40 20 14 67 37 24 18 13 19 48 395 24 41 26 21 16 58 36 22 18 13 17 117 492 124 27 19 22 161 53 32 22 17 12 17 39 528 55 21 23 23 26 48 30 46 16 12 16 25 185 35 18 20 24 28 43 29 51 16 12 15 51 100 28 20 18 25 235 53 32 30 16 12 14 94 71 24 19 19 26 100 53 29 27 16 11 14 107 56 25 20 16 27 50 80 37 24 17 11 16 49 51 26 18 14 28 34 50 62 24 17 10 17 36 57 28 16 15 29 25 42 34 23 --- 11 15 33 96 23 16 79 30 21 40 30 67 9.9 13 35 79 22 19 62 31 22 --- 28 47 9.8 --- 24 --- 95 30 --- TOTAL 1103 3281 1598 1098 636 498.7 810.5 1112.7 2686 1461 1073 807 MEAN 35.6 109 51.5 35.4 22.7 16.1 27.0 35.9 89.5 47.1 34.6 26.9 MAX 235 854 151 131 40 37 110 133 528 124 145 83 MIN 14 21 28 22 16 9.8 8.5 9.7 17 22 16 14 AC-FT 2190 6510 3170 2180 1260 989 1610 2210 5330 2900 2130 1600 CFSM 1.94 5.98 2.82 1.94 1.24 .88 1.48 1.96 4.89 2.58 1.89 1.47 IN. 2.24 6.67 3.25 2.23 1.29 1.01 1.65 2.26 5.46 2.97 2.18 1.64 CAL YR 1986 TOTAL 16789.4 MEAN 46.0 MAX 854 MIN 7.0 AC-FT 33300 CFSM 2.51 IN. 34.13 WTR YR 1987 TOTAL 16164.9 MEAN 44.3 MAX 854 MIN 8.5 AC-FT 32060 CFSM 2.42 IN. 32.86 215 RIO GRANDE DE PATILLAS BASIN 50092000 RIO GRANDE DE PAT1LLAS NEAR PAT1LLAS, PR--Continued (National stream-quality accounting network station) WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1960 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, COLI- STREP- SPE- DIS- FORM, TOCOCCI HARD- STREAM- C1FIC SOLVED FECAL, FECAL, NESS FLOW, CON- PP TEMPER- TUR- OXYGEN, (PER- 0.7 KF AGAR TOTAL INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT UM-ME (COLS. (MG/L DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- (COLS./ PER AS (CFS) (US/CM) UNITS) (DEG C) (FTU) (M/L) ATION) 100 ML) 100 ML) CAC03) OCT 1986 30... 1025 51 162 7.60 25.5 1.2 8.4 104 K1300 640 51 JAN 1987 9... 1140 38 130 7.60 27.0 1.7 7.8 99 K380 400 45 APR 21... 1125 17 164 7.90 26.0 0.6 7.9 99 K880 320 53 JUL 10... 1040 41 154 7.80 26.0 0.8 6.2 77 2400 680 45 HARD- ALKA- NESS MAGNE- SODIUM POTAS- LINITY CHLO- FLUO- SILICA, NONCARB CALCIUM SIUM, SODIUM, SODIUM SIUM, WAT WH SULFATE RIDE, RIDE, DIS- WH WAT DIS- DIS- DIS- AD- DIS- TOT FET DIS- DIS- DIS- SOLVED TOT FLD SOLVED SOLVED SOLVED SORP- SOLVED FIELD SOLVED SOLVED SOLVED (MG/L DATE (MG/L AS (MG/L (MG/L (MG/L TION (MG/L MG/L AS (MG/L (MG/L (MG/L AS CAC03) AS CA) AS MG) AS NA) RATIO AS K) CAC03 AS SO4) AS CL) AS F) SI02) OCT 1986 30... 0 12 5.1 15 0.9 0.7 51 11 11 <0.1 26 JAN 1987 9... 0 9.9 4.9 13 0.9 0.7 46 10 12 <0.1 22 APR 21... 0 12 5.6 14 0.9 0.5 55 12 11 0.1 26 JUL 10... 0 10 4.8 13 0.9 0.7 48 11 10 0.3 24 SOLIDS, SOLIDS, NITRO- NITRO- NITRO- NITRO- PHOS- PHOS- RESIDUE SUM OF SOLIDS, GEM, GEN, GEM, GEN,AM- PHOS- PHOROUS PHATE, AT 180 CONST1- DIS- NO2+003 AMMONIA AMMONIA MONIA PHOS- PHOROUS ORTHO, ORTHO, DEG. C TUENTS, SOLVED DIS- DIS- DIS- ORGANIC PHOROUS DIS- DIS- 01S- DIS- DIS- (TONS SOLVED SOLVED SOLVED TOTAL TOTAL SOLVED SOLVED SOLVED DATE SOLVED SOLVED PER (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L) (MG/L) DAY) AS N) AS N) AS NH4) AS N) AS P) AS P) AS P) AS PO4) OCT 1986 30... 121 113 16.8 0.27 0.04 0.05 0.8 0.03 0.01 0.02 0.06 JAN 1987 9... 97 101 9.95 0.13 0.12 0.15 0.6 <0.01 0.02 0.01 0.03 APR 21... 110 115 5.11 0.17 0.04 0.05 0.7 0.03 0.03 0.02 0.06 JUL 10... 102 103 11.3 <0.10 0.07 0.09 0.7 0.06 0.06 0.03 0.09 ALUM- BERYL- CHRO- INUM, ARSENIC BARIUM, LIUM, CADMIUM M1UM, COBALT, COPPER, IRON, LEAD, DIS- DIS- DIS- DIS- DIS- DIS- DIS- 01$- DIS- DIS- SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS AL) AS AS) AS BA) AS BE) AS CD) AS CR) AS CO) AS CU) AS FE) AS PB) OCT 1986 30... 30 .1 17 <0.5 1 <1 <3 1 33 <5 JAN 1987 9... 40 <1 15 <0.5 <1 <1 <3 2 53 <5 APR 21... <10 1 14 <0.5 ,1 <1 .3 <1 24 ,5 JUL 10... 10 <1 15 <0.5 2 <1 <3 4 41 10 K = non-ideal count 216 RIO GRANDE DE PATILLAS BASIN 50092000 RIO GRANDE OE PATILLAS NEAR PATILLAS. PR--Continued (National stream-quality accounting network station) WATER-QUALITY DATA, WATER YEAR OCTOBER 1985 TO SEPTEMBER 1986 MANGA- MOLYB- SELE- STROH- VANA- LITHIUM NESE, MERCURY DENUM, NICKEL, NIUM, SILVER, TUN, D1UM, ZINC, DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS LI) AS MN) AS HG) AS MO) AS NI) AS SE) AS AG) AS SR) AS V) AS ZN) OCT 1986 30... 4 11 0.1 <10 ,1 <1 <1 40 <6 8 JAN 1987 09... 4 7 0.1 <10 2 <1 <1 36 <6 9 APR 21... <4 10 0.1 <10 2 <1 <1 38 <6 8 JUL 10... <4 18 <0.1 <10 <1 <1 <1 40 <6 12 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT SED. SEDI- SUSP. MENT, SIEVE STREAM- SEDI- DIS- DIAM. FLOW, MENT, CHARGE, PERCENT INSTAN- SUS- SUS- FINER DATE TIME TANEOUS PENDED PENDED THAN (CFS) (MG/L) (T/DAY) .062 MM OCT 1986 30... 1025 51 7 0.96 58 JAN 1987 09... 1140 38 8 0.82 59 APR 21... 1125 17 8 0.37 24 JUL 10... 1040 41 13 1.44 45 Rio 5rande de Moro, 0111M . \ ) \ s) EXPLANATION \.,-' ......./-* d \‘‘, A1080 SURFACE—WATER STATION \--\\ AND NUMBER divide \ 1 1 , V1065 QUALITY—OF—WATER mAIRC,N STATION AND NUMBER 1 , 087 WELL AND WELL NUMBER Rio de In Mato ES VILLA ( \ ( I\N Drainage boundary . Rib inoben boson Island - divide Drainage boundary Guamanr eaCt Rio Seco 1353in Cons! 0 GUAYAMA • 87 NesS ▪SANTA •—v-,.) CENTRAL ISABEL AGUIRRE)u, • / sans de :lobos \ p CARIBBEAN SEA )„AlIVADILLA 4,e,a0 „ FAJARDO t , ‘.,1414YAGUE CA..% S CE l/ K I L OM ET ER S op area Figure 21.--South coast river basins--Rio Salinas to Rio Jacaguas basins. 218 RIO COAMO BASIN 50106500 RIO COAMO NEAR COAMO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18 0352", long 66 2210", Hydrologic Unit 21010004, on Highway 153 bridge, 0.4 mi (0.6 km) above Rio de la Mina, and 1.8 mi (2.9 km) south of Coamo plaza. DRAINAGE AREA.--46.0 sq mi (119.1 sq km). PERIOD OF RECORD.--Water years 1978 to current year. WATER-QUALITY RECORDS, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 13... 1450 40 472 7.75 27.5 12 6.9 89 27 K6500 K1900 DEC 22... 1305 9.0 733 7.75 25.5 1.5 7.9 98 10 380 620 FEB 1987 20... 1250 7.7 658 7.60 28.0 2.0 7.7 100 10 220 410 APR 29... 1210 6.2 602 7.90 32.0 68 6.7 93 44 K1700 68000 JUN 17.., 1225 17 528 8.40 31.0 1.3 10.0 35 240 K91 AUG 19... 1115 9.8 621 8.00 30.0 5.2 K1100 260 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- BIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 13... 190 20 49 17 7.3 0.2 2.7 173 <0.5 26 26 DEC 22... 249 FEB 1987 20... 240 APR 29.., 240 0 63 19 37 1 3.6 230 <0.5 31 39 JUN 17... 210 AUG 19... 270 0 71 23 44 1 4.0 230 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEN, GEM, GEM, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2,4403 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) S102) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 13... 0.2 5.6 238 25.9 32 0.96 0.24 1.20 2.00 0.20 DEC 22... 9 1.82 0.38 2.20 0.70 0.40 FEB 1987 20... 26 1.90 0.30 2.20 0.75 0.75 APR 29... 0.2 32 360 6.02 328 1.24 0.26 1.50 0.40 2.2 JUN 17... 7 1.06 0.19 1.30 0.60 1.2 AUG 19... 0.2 35 413 10.9 4 1.11 0.19 1.30 0.60 1.2 K . non-ideal count -- 219 RIO COAMO BASIN 50106500 RIO COAMO NEAR COAMO, PR--Continued WATER-QUALITY RECORDS, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 13... 2.2 3.4 0.75 1 <100 <10 1 <1 10 DEC 22... 1.1 3.3 15 0.87 FEB 1987 20... 1.5 3.7 16 0.93 APR 29... 2.6 4.1 18 1.10 1 <100 80 1 32 50 JUN 17... 1.3 2.6 0.59 AUG 19... 1.8 3.1 0.76 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) NOV 1986 13... 1400 23 60 <0.1 <1 <1 20 <0.01 10 0.07 DEC 22.,. FEB 1987 20... APR 29... 11000 21 590 <0.1 <1 <1 80 <0.01 5 0.07 JUN 17... AUG 19... RIO DESCALABRADO BASIN 220 50108000 RIO DESCALABRADO NEAR LOS LLANOS, PR LOCATION.--Lat 18•03 1 01.1", long 66°25'34", Hydrologic Unit 21010004, at bridge on Highway 14, 1.5 mi (2.4 km) west of Los Llanos, and 5.3 mi (8.5 km) east of Juana Diaz. DRAINAGE AREA.--12.9 mi2 (33.4 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--1959-65 (annual low-flow measurements only), 1965 (annual maximum discharge), January 1966 to June 1969. July to December 1969 (maximum discharge only), February 1984 to current year. GAGE.--Water-stage recorder. Elevation of gage is 220 ft (67 m), from topographic map. REMARKS,--Records fair except those for estimated daily discharges, which are poor. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 30,000 ft,/s (850 m 3/s), Oct. 7. 1985, gage height, 24.37 ft (7.43 m), from rating curve extended above 10.000 ft'/s (283 m'is) on basis of step-backwater analysis; no flow many days. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 1,500 ft'is (42.5 m'is) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft,/s) (0/s) (ft) (m) Date Time (W/s) (m 3/s) (ft) (m) June 3 1845 *1,420 40.2 *7.58 2.310 Minimum daily discharge, 0.28 ft'is (0.008 m'/s), Apr. 3-4. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 1.3 1.4 e.95 e.78 el.0 e.34 .33 .55 3.1 el0 2.5 e.86 2 1.3 1.3 e.90 e.76 e.90 e.33 .30 .55 180 e7.0 1.8 e.84 3 1.1 1.3 el.6 e.75 e.85 e.32 .28 .56 116 e5.0 2.6 e.82 4 1.1 1.3 el.4 el.0 e.80 e.31 .28 .55 e20 e4.5 2.1 .80 5 39 1.3 el.3 el.5 .79 e.30 .51 1.5 e9.0 e4.0 2.4 .80 6 6.8 14 el.1 e2.0 .76 e.30 47 1.2 e7.5 e3.7 1.8 .80 7 3.3 2.3 el.0 el.8 e.72 .34 2.3 .90 e6.0 e4.0 1.7 .86 8 e2.8 1.5 e.95 el.6 e.70 .33 1.0 3.7 e5.5 e4.3 1.6 1.4 9 e2.6 1.4 e.90 el.5 e.67 .33 .96 1.9 e28 e3.7 1.6 1.3 10 e2.4 1.4 e.85 el.4 e.65 .33 .88 5.5 e7.0 e3.4 1.6 1.1 11 e2.2 1.3 e.82 el.4 .73 .32 2.5 1.5 e6.0 e3.2 1.4 1.0 12 e2.1 34 e.80 e1.3 .66 .31 4.0 1.0 e5.5 3.1 1.3 1.0 13 e2.0 3.5 e.78 el.3 2.5 .31 .90 .65 e5.0 2.8 1.3 1.0 14 e2.0 2.6 e.76 el.2 5.6 .30 .77 .65 e5.0 2.6 1.9 1.1 15 e2.2 1.6 e.74 el.2 1.5 .36 .67 .65 e15 2.6 2.7 1.7 16 e2.0 20 e.72 el.1 .74 .34 .65 .58 e6.0 2.4 1.7 2.0 17 el.9 3.7 e.71 0.1 e.65 .33 .83 20 e5.0 2.3 1.2 1.5 18 e1.8 2.0 e.70 el.0 e.57 .31 .69 3.4 e20 2.3 3.9 i.6 19 el.7 3.5 el.5 el.0 e.52 .29 .62 9.2 e7.0 2.3 2.1 1.9 20 el.7 1.3 e2.0 e.95 e.48 .30 .60 2.3 40 2.3 1.5 1.4 21 el.8 .93 el.5 e.92 e.45 .30 .57 1.3 123 3.7 1.2 1.2 22 4.1 15 el.3 e.90 e.43 .30 .58 1.9 79 3.1 1.0 1.3 23 e3.0 2.2 el.2 el.5 e.41 .30 .56 2.3 ell 2.5 .97 1.4 24 e2.7 1.3 el.1 el.4 e.39 .36 .55 4.1 e8.0 2.4 .94 1.2 25 6.4 2.9 el.0 el.2 e.38 .33 .55 4.1 e6.0 2.1 .97 .92 26 3.5 1.3 e.95 el.0 e.37 .31 .55 1.6 e5.0 2.0 e.90 .72 27 97 3.5 e.90 e.95 e.36 .30 .55 1.2 e4.5 1.8 e.86 .69 28 5.5 e1.5 e.87 e.90 e.35 .31 .54 1.2 e4.0 1.9 e.84 .65 29 e6.0 el.2 e.84 el.0 --- .31 .52 19 el3 1.7 e.82 .65 30 2.3 el.0 e.82 el.5 .31 .53 8.1 0.0 1.6 e.80 .67 31 1.7 --- e.80 el.2 .30 --- 3.4 --- 2.7 .96 --- TOTAL 215.3 131.53 31.76 37.11 24.93 9.83 71.57 105.04 757.1 101.0 48.96 33.18 MEAN 6.95 4.38 1.02 1.20 .89 .32 2.39 3.39 25.2 3.26 1.58 1.11 MAX 97 34 2.0 2.0 5.6 .36 47 20 180 10 3.9 2.0 MIN 1.1 .93 .70 .75 .35 .29 .28 .55 3.1 1.6 .80 .65 AC-FT 427 261 63 74 49 19 142 208 1500 200 97 66 CFSM .54 .34 .08 .09 .07 .02 .18 .26 1.96 .25 .12 .09 IN. .62 .38 .09 .11 .07 .03 .21 .30 2.18 .29 .14 .10 CAL YR 1986 TOTAL 2406.29 MEAN 6.59 MAX 686 MIN .70 AC-FT 4770 CFSM .51 IN. 6.94 WTR YR 1987 TOTAL 1567.31 MEAN 4.29 MAX 180 MIN .28 AC-FT 3110 CFSM .33 IN. 4.52 e Estimated RIO JACAGUAS BASIN 221 50111500 RIO JACAGUAS AT JUANA DIAZ, PR LOCATION.--Lat 18°0316", long 66°30'40, Hydrologic Unit 21010004, on Highway 14 bridge, 0.4 ml (0.6 km) west of Juana Diaz plaza, and 4.0 mi (6.4 km) downstream from Lago Guayabal. DRAINAGE AREA.--49.8 mi' (129.0 ke),. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1984 to current year. GAGE.--Water-stage recorder. Elevation of gage is 131 ft (40 m), from topographic map. REMARKS.--Records fair. Flow regulation from Lago Guayabal. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 40,000 ft'is (1,130 m 3 /s), Oct. 7, 1985, gage height, 29.42 ft (8.967 m) from rating curve extended above 500 ft'is (14.2 mi/s) on basis of step-backwater analysis and logarithmic extension; minimum daily discharge, 1.2 ft'is (0.034 e/s), May 18, 1984. EXTREMES FOR CURRENT YEAR.--Maximum discharge, 4,920 ft'is (139 10/s), June 3, gage height, 13.52 ft (4.121 m) from rating curve extended above 500 ft'is (14.2 10/s) on basis of step-backwater analysis and logarithmic extension; minimum daily discharge 3.6 ft'/s (0.102 m'/s). Mar. 29, DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 6.6 9.9 19 5.3 7.4 e5.6 4.0 7.8 70 151 16 11 2 6.6 9.5 36 4.9 6.6 e5.6 4.0 7.8 173 117 8.5 7.4 3 6.7 9.5 14 4.9 4.6 e5.7 4.2 7.8 499 109 7.0 7.1 4 6.6 9.4 11 4.9 5.1 e6.1 4.2 8.0 221 106 31 7.1 5 6.6 9.0 10 5.2 5.0 6.4 4.2 8.6 169 94 54 6.3 6 6.6 9.2 e9.6 5.3 4.9 6.2 7.4 8.7 145 69 45 6.1 7 6.6 9.5 e9.4 5.3 4.9 6.1 11 8.8 87 96 129 5.8 8 6.6 9.5 e9.3 4.9 4.9 6.1 .0 14 44 109 11 5.2 9 6.6 9.3 e9.2 4.6 4.9 5.8 .5 11 149 71 10 5.8 10 6.6 9.0 e9.1 4.5 5.4 5.2 .4 9.9 126 118 47 5.8 11 6.6 9.0 e9.0 4.4 6.3 4.8 .9 13 120 31 11 5.8 12 6.6 31 e9.0 4.4 6.5 5.2 .5 9.5 81 75 8.4 5.9 13 6.6 13 e9.0 4.4 10 4.9 .5 8.8 84 192 8.5 5.8 14 6.6 8.5 e8.9 5.4 25 4.8 .4 8.6 72 101 52 13 15 6.7 7.1 e8.9 5.5 11 4.7 .9 9.5 46 93 11 14 16 6.7 26 e8.9 5.3 6.7 4.7 .7 11 128 160 9.5 9.0 17 6.7 10 e8.8 5.6 5.5 4.7 .9 10 88 17 8.9 6.6 18 6.6 9.0 e8.8 7.0 5.5 4.7 .1 12 121 13 8.8 7.4 19 6.6 8.6 e8.8 6.7 5.5 4.3 .1 296 128 25 22 8.3 20 6.6 7.8 e9.2 5.9 5.6 4.2 .5 201 402 61 9.5 7.1 21 6.6 7.1 e9.6 6.1 6.1 4.2 .1 142 595 123 8.4 7.1 22 6.7 12 e9.8 6.1 e5.9 4.0 .0 140 904 121 7.4 24 23 9.3 9.4 10 6.3 e5.8 4.0 .2 127 315 103 7.3 23 24 13 8.2 10 6.4 e5.8 4.3 .2 564 299 32 7.0 18 25 14 10 9.2 6.4 e5.7 4.7 .2 507 285 60 6.7 8.7 26 13 11 8.6 7.1 e5.7 4.3 .2 326 209 28 6.8 7.0 27 19 8.9 8.4 8.1 e5.6 4.1 .1 184 170 35 7.1 6.1 28 17 8.6 7.5 8.2 e5.6 4.1 .1 135 103 80 7.1 6.4 29 16 8.6 5.9 8.0 --- 3.6 .2 120 74 38 8.7 6.4 30 11 8.6 5.6 7.7 3.7 .8 201 37 56 14 9.9 31 10 --- 5.5 7.4 3.8 66 --- 70 13 --- TOTAL 268.0 316.2 316.0 182.2 187.5 150.6 200.5 3183.8 5944 2554 601.6 267.1 MEAN 8.65 10.5 10.2 5.88 6.70 4.86 6.68 103 198 82.4 19.4 8.90 MAX 19 31 36 8.2 25 6.4 11 564 904 192 129 24 MIN 6.6 7.1 5.5 4.4 4.6 3.6 4.0 7.8 37 13 6.7 5.2 AC-FT 532 627 627 361 372 299 398 6320 11790 5070 1190 530 CAL YR 1986 TOTAL 10571.3 MEAN 29.0 MAX 2150 MIN 1.6 AC-FT 20970 WTR YR 1987 TOTAL 14171.5 MEAN 38.8 MAX 904 MIN 3.6 AC-FT 28110 e Estimated 222 THIS PAGE WAS LEFT BLANK INTENTIONALLY Rio Grande de Area o 6asin Rior m t a7rIeba Drainage boundary p,5 Grande de AAaeco basin • ( Drainage boundarY-\ Rro Guanajibo bar6n • 125 miSABANA GRANDE • 7h.ogo Loco "! JUANA DIA Z V ega Bronce Sohia QM ENSENADA 1297 _.. GUAN1CA 1 de Suafre,./1.0 71, / / 8 ah,:e de relloboo PLAYS'' DE 'PONCE\ „3 vThj 7 . , \I _ CARIBBEAN EXPLANATION AI 125 SURFACE—WATER STATION AND NUMBER V1140 QUALITY—OF—WATER STATION AND NUMBER sun JuAn •141 WELL AND WELL NUMBER FAIJAREI CASLIA.S. i• 8UAYAMA --e-­ 5 KILOME, —RS L-Mop area ES Figure 22.--South coast river basins--Rio Inabon to Rio Loco basins. RIO INABON BASIN 224 50112500 RIO INABON AT REAL ABAJO, PR LOCATION.--Lat 18°0510", long 66°33'46", Hydrologic 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 Abajo, and 6.1 mi (9.8 km) northeast of Plaza Degetau in Ponce. DRAINAGE AREA.--9.70 mi' (25.12 km 2). WATER-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. National Weather Service gage-height at station. AVERAGE DISCHARGE.--21 years (1965-69. 1972-87), 18.8 ft'A (0.532 10/s), 26.32 in/yr (669 mm/yr). 13,620 acre-ft/yr (16.8 hoe/yr); median of yearly mean discharges, 18 ft'A (0.51 se/s), 13,000 acre-ft/yr (16 hmYyr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 19,000 ft'is (538 m 3/s), Oct. 7, 1985, gage height, 25.3 ft (7.71 m), datum then in use, from floodmark, from rating curve extended above 30 ft'is (0.850 m 3/s) on basis of contracted opening and flow-over-road measurements of peak flow; minimum daily discharge, 0.80 ft'is (0.023 m 3/s), July 23, 1977. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 500 ft7s (14.2 10/s), and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft'/s) (0/s) (ft) (m) Date Time (ft'/s) (m 3/s) (ft) (m) Oct. 28 1630 *1,080 30.6 *11.44 3.487 May 17 1630 736 20.8 8.63 2.630 Nov. 17 1645 579 16.4 7.26 2.213 June 18 1500 659 18.7 7.96 2.426 Minimum discharge. 2.8 ft'is (0.079 m 3/s). Mar. 29-31, Apr. 1, 2. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 6 0 19 45 7.2 6.7 5.0 2.8 9.5 44 21 6.6 9.4 2 30 15 28 7.2 6.4 5.0 2.9 3.9 47 20 5.3 7.6 3 28 27 21 7.8 5.9 4.8 3.1 3.6 56 20 6.6 7.0 4 18 20 17 7.8 5.9 4.8 3.3 3.6 50 18 8.3 6.7 5 13 14 15 13 5.9 4.8 3.3 4.5 38 17 7.7 6.0 6 36 17 14 20 5.9 4.8 17 5.4 34 15 6.8 5.4 7 29 16 13 14 5.9 4.8 8.2 4.3 32 15 6.1 23 8 19 13 12 8.5 5.9 4.6 4.4 7.3 30 15 5.9 20 9 15 12 12 7.5 5.9 4.1 3.8 31 46 15 6.0 13 10 12 11 11 7.1 7.1 4.0 5.0 36 42 15 7.6 10 11 12 9.6 11 6.7 9.7 4.0 16 17 37 15 6.3 12 12 11 44 10 6.5 8.4 4.6 22 9.9 36 15 6.6 13 13 11 29 9.9 6.2 14 3.9 7.7 8.4 35 15 8.7 9.1 14 11 19 9.9 6.2 14 3.7 6.0 6.8 33 14 9.9 16 15 12 15 9.9 6.2 9.1 3.7 7.3 4.8 46 14 14 11 16 11 54 9.3 6.2 6.7 3.9 4.8 5.3 44 13 11 8.2 17 10 76 8.9 6.1 5.9 3.8 4.4 46 39 12 11 6.4 18 12 45 8.5 5.9 5.4 3.6 4.0 55 66 14 15 6.7 19 12 37 9.4 5.9 5.4 3.7 3.6 49 40 12 12 7.7 20 12 33 10 5.9 5.8 3.7 3.7 37 83 10 9.9 12 21 9.9 27 10 5.9 5.3 3.6 3.5 28 66 12 7.7 13 22 10 27 9.5 5.9 5.0 3.3 3.3 25 110 9.3 6.8 21 23 10 24 9.0 7.2 5.0 3.0 3.2 28 44 8.2 6.1 14 24 18 20 8.5 7.4 5.0 3.2 3.0 36 30 7.8 5.3 11 25 21 23 8.2 6.1 5.0 3.7 e3.5 51 24 7.1 5.8 21 26 23 20 8.1 5.9 5.0 3.4 e4.0 42 21 6.2 5.7 13 27 54 33 8.1 5.9 5.0 3.0 e4.0 36 21 6.6 5.0 9.8 28 114 24 8.1 5.9 5.0 3.0 e3.7 30 22 6.5 4.5 7.9 29 67 20 8.0 5.9 --- 3.0 3.3 39 24 6.3 4.8 6.8 30 37 31 7.8 7.2 2.8 9.1 45 22 6.0 4.9 8.6 31 25 --- 7.7 6.6 2.8 --- 33 --- 7.3 15 --- TOTAL 708.9 774.6 377.8 231.8 186.2 120.1 173.9 741.3 1262 388.3 242.9 336.3 MEAN 22.9 25.8 12.2 7.48 6.65 3.87 5.80 23.9 42.1 12.5 7.84 11.2 MAX 114 76 45 20 14 5.0 22 55 110 21 15 23 MIN 6.0 9.6 7.7 5.9 5.0 2.8 2.8 3.6 21 6.0 4.5 5.4 AC-FT 1410 1540 749 460 369 238 345 1470 2500 770 482 667 CFSM 2.36 2.66 1.26 .77 .69 .40 .60 2.47 4.34 1.29 .81 1.16 IN. 2.72 2.97 1.45 .89 .71 .46 .67 2.84 4.84 1.49 .93 1.29 CAL YR 1986 TOTAL 4799.6 MEAN 13.1 MAX 325 MIN 2.4 AC-FT 9520 CFSM 1.36 IN. 18.41 WTR YR 1987 TOTAL 5544.1 MEAN 15.2 MAX 114 MIN 2.8 AC-FT 11000 CFSM 1.57 IN. 21.26 e Estimated 225 RIO INABON BASIN 50112500 RIO INABON AT REAL ABAJO, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1986 TO SEPTEMBER 1987 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) DEC, 29 1329 8.22 252 25.5 MAY, 13 1521 0.50 286 28.5 JAN, 27 1139 5.90 290 25.0 JUL, 02 1104 19.4 248 30.0 FEB, 24 1233 5.14 256 25.5 AUG, 26 1134 6.15 245 29.5 MAR, 26 1137 3.53 279 27.0 RIO BUCANA BASIN 228 50114000 RIO CERRILLOS NEAR PONCE, PR Location.--Lat 18°0415, long 66°34'51", Hydrologic unit 21010004, on right bank off Highway 139, 2.3 ml (3.7 km) upstream from Quebrada Ausubo and 4.6 ml (7.4 km) northeast of Plaza Degetau in Ponce. DRAINAGE AREA.--17.8 sq ml (46.1 Sq km) WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1964 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR 1NSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 07... 1150 35 257 7.95 24.5 6.9 8.8 107 13 K10 350 DEC 12... 1220 24 279 8.00 23.5 9.6 114 90 50 FEB 1987 06... 1210 11 242 8.30 24.5 3.7 11.6 141 <10 K22 42 APR 10... 1315 7.6 294 8.20 29.0 18 7.8 103 20 230 K1000 JUN 05... 1130 68 252 8.30 25.5 12 7.6 <10 41000 960 AUG 07... 1140 9.2 320 8.70 30.5 16 7.6 16 K110 180 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM S1UM, SODIUM, AD- SIUM, WAT WH SULFATE TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLO SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 07... 120 10 37 6.1 9.1 0.4 1.1 108 <0.5 33 6.5 DEC 12... FEB 1987 6... 98 APR 10... 130 5 41 6.6 13 0.5 2.0 125 <0.5 19 9.4 JUN 05... 110 AUG 7... 110 2 34 6.6 12 0.5 1.4 110 18 8.6 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) 202) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 07... <0.1 22 180 17.0 23 0.89 0.01 0.90 0.01 0.29 DEC 12... <0.01 0.50 <0.01 FEB 1987 6... 9 <0.01 0.20 <0.01 APR 10... 0.2 21 187 3.84 116 0.69 0.01 0.70 0.04 0.56 JUN 05... 36 0.86 0.04 0.90 0.07 0.63 AUG 7... 0.1 22 170 4.22 9 0.09 0.01 0.10 0.05 0.35 K = non-ideal count 227 RIO BUCANA BASIN 50114000 RIO CERRILLOS NEAR PONCE, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM. BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (KA (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 07... 0.3 1.2 0.07 <1 <100 <10 <1 <1 10 DEC 12.., 1.1 1.6 7.1 0.03 FEB 1987 06... 0.5 0.7 3.1 0.02 APR 10... 0.6 1.3 5.8 0.15 <1 100 20 <1 2 10 JUN 05... 0.7 1.6 0.04 AUG 07... 0.4 0.5 0.03 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) NOV 1986 07... 1900 5 70 <0.1 <1 <1 2(., 0.01 <1 0.04 DEC 12... FEB 1987 6... APR 10... 4400 6 200 <0.1 <1 <1 20 <0.01 4 0.01 JUN 05.., AUG 7... RIO PORTUGUES BASIN 228 50115000 RIO PORTUGUES NEAR PONCE, PR LOCATION.--Lat 18°04'45", long 66°38'01', Hydrologic Unit 21010004, on right bank 30 ft (9 m) upstream from brid9e 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 AREA.--8.82 mi' (22.84 km 2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February to June 1964 (monthly measurements only), July 1964 to current year. GAGE.--Water-stage recorder. Elevation of gage is 470 ft (143 m), from topographic map. Prior to Dec. 4, 1964, non-recording gage at same site and datum. REMARKS.--Records fair. National Weather Service gage-height telemeter at station. Some low-flow regulation due to unknown activity upstream. AVERAGE DISCHARGE.--23 years (1965-87), 18.7 ft'is (0.530 m'/s), 28.79 in/yr (731 mm/yr), 13,550 acre-ft/yr (16.7 he/yr); median of yearly mean discharges, 18 ft3/s (0.52 m 3/s). 13,300 acre-ft/yr (16 he/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 21,000 ft'is (595 10/s), Oct. 7, 1985, gage height, 20.2 ft (6.16 m), from floodmarks at downstream side of bridge, from rating curve extended above 150 ft'is (4.25 e/s) on basis of slope-area measurement of peak flow; minimum discharge, 1.0 ft'is (0.028 m 3/s), May 29. 1973, EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 800 ft'is (22.6 m'/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (W/s) (10/s) (ft) (m) Date Time (W/s) (m3/s) (ft) (m) Oct. 23 2015 971 27.5 6.24 1.902 Nov. 16 1545 1,330 37.7 6.97 2.124 Oct. 27 1500 *1,510 42.8 *7.33 2.234 Minimum discharge, 1.8 ft'is (0.051 40/s), Aug. 28, 31. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 5.6 30 59 8.4 6.8 4.6 2.3 5.7 66 7.9 e5.4 67 2 32 23 49 8.4 6.2 4.6 2.4 5.2 143 7.3 e7.0 37 3 14 40 31 8.3 6.1 4.7 2.2 5.8 113 6.5 el0 18 4 8.0 26 22 8.4 6.2 4.6 2.1 4.3 126 e7.2 e6.4 11 5 7.8 17 18 18 6.0 4.3 2.1 4.8 38 e6.6 e5.4 8.8 6 7.1 27 15 49 5.8 4.2 6.7 e4.0 23 e6.0 e5.2 8.4 7 7.4 26 14 26 5.7 4.2 7.7 e4.5 20 e9.4 e5.0 9.3 8 6.7 19 12 10 5.5 4.1 4.4 e5.0 17 e13 e8.0 22 9 28 17 11 8.6 5.4 4.1 4.1 el0 22 e7.0 5.7 29 10 14 16 10 8.1 8.0 4.1 3.8 e70 13 e6.0 5.4 46 11 9.2 13 9.7 7.6 14 4.2 5.9 e60 10 e5.6 4.8 19 12 7.4 65 12 7.5 11 4.0 32 e54 8.5 e5.4 4.6 9.0 13 13 43 11 7.2 34 3.6 21 51 7.5 e6.0 6.0 6.0 14 9.4 20 11 7.1 22 3.1 26 55 7.9 9.1 4.2 16 15 9.7 15 9.7 7.3 9.9 3.5 14 35 9.8 10 5.2 P9 16 8.1 116 9.2 7.0 6.9 4.3 8.9 25 8.2 e7.0 4.8 64 17 7.4 107 9.0 6.7 6.3 3.2 10 52 6.9 e6.6 8.3 29 18 6.4 92 11 6.9 5.9 3.2 7,3 60 6.4 e6.8 13 19 19 16 67 10 6.9 5.5 3.5 6.9 43 7.0 e6.8 8.0 15 20 12 61 8.4 6.9 5.1 2.9 7.4 33 84 e6.8 5.2 18 21 10 54 8.5 6.5 5.0 2.7 7.0 26 92 e7.0 4.4 14 22 18 55 8.2 6.3 4.9 2.7 7.3 24 182 e6.4 3.9 48 23 75 44 8.3 11 5.1 2.6 7.7 21 66 e6.0 3.8 28 24 53 30 9.4 8.6 5.1 2.8 7.9 33 40 e6.2 12 17 25 24 33 9.4 6.6 5.0 2.8 8.7 51 24 ell 15 15 26 26 25 9.0 6.5 5.0 2.5 8.3 49 18 OA 5.7 12 27 112 25 10 7.2 5.2 2.5 7.0 37 15 e6.4 2.7 11 28 87 18 9.7 6.4 4.7 2.4 7.4 33 12 e5.8 2.0 20 29 103 15 9.1 6.6 --- 2.3 6.9 55 11 e5.2 3.1 14 30 70 47 8.9 9.9 2.2 6.4 97 9 6 e9.0 16 12 31 45 --- 8.5 7.6 2.2 --- 43 --- e9.0 62 --- TOTAL 852.2 1186 441.0 307.5 222.3 106.7 251.8 1056.3 1206.8 226.0 258.2 731.5 MEAN 27.5 39.5 14.2 9.92 7.94 3.44 8.39 34.1 40.2 7.29 8.33 24.4 MAX 112 116 59 49 34 4.7 32 97 182 13 62 89 MIN 5.6 13 8.2 6.3 4.7 2.2 2.1 4.0 6.4 5.2 2.0 6.0 AC-FT 1690 2350 875 610 441 212 499 2100 2390 448 512 1450 CFSM 3.12 4.48 1.61 1.12 .90 .39 .95 3.86 4.56 .83 .94 2.76 IN. 3.59 5.00 1.86 1.30 .94 .45 1.06 4.46 5.09 .95 1.09 3.09 CAL YR 1986 TOTAL 7361.7 MEAN 20.2 MAX 500 MIN 3.0 AC-FT 14600 CFSM 2.29 IN. 31.05 WTR YR 1987 TOTAL 6846.3 MEAN 18.8 MAX 182 MIN 2.0 AC-FT 13580 CFSM 2.13 IN. 28.88 e Estimated 229 RIO PORTUGUES BASIN 50115000 RIO PORTUGUES NEAR PONCE, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1964 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTJ) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 07... 0910 22 211 7.95 22.5 6.3 9.0 106 <10 K91 520 DEC 12... 0905 14 290 7.95 21.0 8.8 100 98 K150 FEB 1987 06... 0905 5.7 297 7.80 20.0 0.4 9.9 111 <10 44 K150 APR 10... 0930 3.8 301 8.20 23.5 0.6 9.1 110 <10 96 620 JUN 05... 0825 37 250 8.40 23.0 2.3 8.2 <10 K890 830 AUG 07... 0855 5.7 390 8.6 25.0 10 6.4 12 240 K140 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- BIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 07... 96 3 30 5.2 7.3 0.3 1.2 93 <0.5 7.6 6.3 DEC 12... 132 FEB 1987 6... 140 APR 10... 140 0 42 7.9 11 0.4 1.3 140 <0.5 11 9.1 JUN 05... 110 10 AUG 7... 150 0 46 8.3 13 0.5 1.6 150 9.3 10 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOtVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 07... <0.1 19 132 7.86 11 1.09 0.01 1.10 0.01 0.19 DEC 12... 0.99 0.01 1.00 0.01 0.29 FEB 1987 6... -- 6 0.89 0.01 0.90 0.01 0.59 APR 10... 0.2 21 187 1.92 <1 0.89 0.01 0.90 0.01 0.29 JUN 05... 9 1.39 0.01 1.40 0.02 0.18 AUG 7... 0.1 22 200 3.08 18 0.59 0.01 0.60 0.03 0.27 K - non-ideal count 230 RIO PORTUGUES BASIN 50115000 RIO PORTUGUES NEAR PONCE, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 10 SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA t NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 07... 0.2 1.3 0.05 <1 <100 <10 <10 <1 <1 DEC 12... 0.3 1.3 5.8 0.05 FEB 1987 06... 0.6 1.5 6.6 0.04 APR 10... 0.3 1.2 5.3 0.05 <1 <100 <10 <1 5 <10 JUN 05... 0.2 1.6 0.03 AUG 07... 0.3 0.9 0.19 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELF- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) NOV 1986 07... 430 <5 20 <0.1 <1 1 <10 <0.01 1 0.04 DEC 12... FEB 1987 6... APR <1 10... 30 9 <10 <0.1 <1 <10 <0.01 13 0.02 JUN 05... AUG 7... 231 RIO PORTUGUES BASIN 50116200 RIO PORTUGUES AT PONCE, PR WATER-QUALITY RECORDS LOCATION.--Lat 180020", long 66°3628, 1,300 ft (400 m) south of Las Americas Avenue Bridge, 1.2 ml (1.9 km) south of CSC 50115900, 0.8 mi (1.3 km) west of Highways 1 and 2 junction, and 0.7 mi (1.1 km) southeast of Ponce. DRAINAGE AREA.--18.9 sq mi (49.0 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIF1C SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 Kr AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 13... 1125 59 326 8.00 26.0 310 7.9 48 49 56000 26000 DEC 22... 1020 11 439 7.80 24.0 3.1 7.7 91 83 1(9800 2000 FEB 1987 20... 1005 4.6 457 7.40 22.5 7.5 7.5 87 <10 1(6500 980 APR 29... 0930 3.2 518 8.10 25.5 1.8 7.9 97 <10 5800 220 JUN 17... 0925 16 347 8.30 26.5 46 7.6 <10 3700 2300 AUG 19... 0845 16 318 8.10 26.0 38 6.0 15 1(18000 K48000 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- S1UM, WAT WH SULFATE RIDE, TOTAL WI's WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED T1ON SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 13... 110 0 33 6.9 14 0.6 1.6 131 <0.5 16 11 DEC 22... 180 FEB 1987 20... 160 APR 29... 190 16 53 13 42 1 2.2 170 <0.5 59 36 JUN 17... 150 AUG 19... 130 0 37 8.3 18 0.7 1.8 130 23 13 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEM, GEM, GEM, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) 5IO2) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 13... 0.2 19 180 28.8 708 0.90 0.10 1.00 0.26 0.44 DEC 22... 5 1.08 0.02 1.10 0.41 0.16 FEB 1987 20... 32 0.58 0.02 0.60 0.06 0.84 APR 29... 0.3 20 330 2.85 3 0.47 0.03 , 0.50 0.11 2.2 JUN 17... 101 0.66 0.04 0.70 0.09 0.31 AUG 19... 0.2 21 200 8.64 73 0.67 0.03 0.70 0.06 0.94 K non-ideal count 232 RIO PORTUGUES BASIN 50116200 RIO PORTUGUES AT PONCE. PR--Continued WATER-QUALITY DATA, WATER YEAR OCTObER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 13... 0.7 1.7 0.17 1 100 <10 ..-1 3 70 DEC 22... 0.2 1.3 0.06 FEB 1987 20... 0.9 1.5 6.6 0.07 APR 29... 2.3 2.8 12 0.06 1 100 90 <1 1 10 JUN 17... 0.4 1.1 0.07 AUG 19... 1.0 1.7 0.15 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) NOV 1986 13... 25000 9 730 0.1 <1 1 100 <0.01 11 0.05 DEC 22... FEB 1987 20... APR 29... 320 5 80 0.1 <1 1 10 <0.01 7 0.03 JUN 17... AUG 19... 233 RIO GUAYANILLA BASIN 50124200 RIO GUAYANILLA NEAR GUAYANILLA, PR LOCATION.--Lat 18°02'40", long 66°47'53', Hydrologic Unit 21010004, on left bank, 0.7 ml (1.1 km) north of junction of Highways 2 and 132. 0.6 mi (1.0 km) downstream from Quebrada Consejo, 1.8 mi (2.9 km) north-northwest from Plaza de Guayanilla. DRAINAGE AREA.--18.9 eV (49.0 km 2 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1981 to current year. GAGE.--Water-stage recorder. Elevation of gage is 80 ft (24 m) from topographic map. REMARKS.--Estimated daily discharges: Oct. 1, Oct. 30 to Nov. 14. Records fair except those for estimated daily discharges, which are poor. National Weather Service gage-height telemeter at station. AVERAGE DISCHARGE.--6 years (1982-87), 23.6 ft3/s (0.668 10/s), 16.96 in/yr (431 mm/yr), 17,100 acre-ft/yr (21.1 hiP/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 14,700 ft'is (416 03/s), Sept. 12, 1982, gage height, 20.4 ft (6.21 0, from floodmarks, from rating curve extended above 100 ft'/s (2.83 e/s) on basis of step-backwater analysis and indirect measurement of peak flow; minimum discharge, 1.8 ft'is (0.051 mYs), Apr. 17-19, 1981. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 800 ft'is (22.7 m'/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (W/s) (m'/s) (ft) (m) Date Time (ft'/s) (03/s) (ft) (s) Oct. 2 1630 *1,210 34.3 *10.17 3.100 Nov. 25 1430 885 25.1 9.48 2.890 Oct. 27 1645 876 24.8 9.46 2.883 May 25 1915 1,170 33.1 10.09 3.075 Oct. 29 1445 836 23.7 9.36 2.853 Sept. 14 1300 944 26.7 9.62 2.932 Nov. 16 1615 1,190 33.7 10.14 3.091 Sept. 15 1645 824 23.3 9.33 2.844 Nov. 17 1845 880 24.9 9.47 2.886 Minimum discharge, 3.8 ft'is (0.108 10/s), Aug. 24. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 20 40 66 13 7.9 6.5 4.8 5.6 80 14 8.7 110 2 178 35 56 13 7.4 6.6 4.9 7.3 125 13 6.0 31 3 44 70 44 12 7.1 6.5 4.6 6.4 115 12 8.1 17 4 28 50 38 11 6.7 6.6 4.4 6.1 136 12 9.8 10 5 37 40 35 15 6.7 6.4 6.8 5.3 51 14 6.4 8.3 6 32 45 31 68 6.7 6.2 134 5.7 35 12 5.4 7.1 7 25 35 32 30 6.3 5.9 34 5.4 30 14 5.2 6.5 8 19 30 28 16 6.3 5.9 11 5.9 29 19 5.0 8.9 9 14 25 26 14 6.2 5.9 7 9 9.1 32 14 7.3 8.7 10 12 20 24 13 6.7 5.9 6 9 54 23 12 5.8 19 11 16 15 24 13 22 6.0 12 48 19 11 5.1 15 12 14 150 22 13 13 6.2 17 41 18 11 4.7 8.0 13 12 90 21 13 44 5.5 14 41 17 11 5.5 7.1 14 12 60 21 12 40 5.6 15 28 22 9.6 5.1 100 15 10 34 19 11 19 5.5 42 15 30 11 5.2 122 16 9.3 258 51 10 12 5.8 26 12 17 11 5.8 48 17 8.0 317 28 10 10 6.0 19 9.4 13 8.7 5.7 17 18 7.5 214 30 9.6 9.4 5.6 12 64 12 8.1 8.0 13 19 7.4 123 28 9.4 8.5 5.5 10 34 12 8.2 10 10 20 7.3 119 20 9.8 8.0 5.2 9.0 17 94 8.2 7.8 17 21 7.2 90 18 9.5 7.7 5.1 7.7 16 35 8.3 6.3 11 22 15 76 17 9.0 7.5 5.2 7.2 30 100 8.3 5.0 40 23 7.4 118 16 12 7.4 5.2 6.8 12 44 7.1 4.4 26 24 9.3 98 15 11 7.1 5.0 6.5 18 27 7.0 4.0 15 25 18 237 15 9.2 7.0 19 6.2 228 23 7.3 9.8 15 26 16 99 15 9.2 7.0 7.1 5.9 121 21 10 12 9.8 27 174 138 14 11 7.2 5.2 6.1 34 18 7.5 5.3 8.5 28 112 83 14 9.3 6.9 4.8 5.9 22 16 6.8 8.2 7.8 29 222 57 13 9.1 --- 4.9 5.6 17 16 6.0 87 9.1 30 90 94 13 9.4 4.8 5.5 19 19 5.6 32 13 31 60 --- 14 8.0 4.5 --- 27 --- 8.7 19 --- TOTAL 1243.4 2860 808 422.5 311.7 190.1 458.7 964.2 1229 316.4 323.6 738.8 MEAN 40.1 95.3 26.1 13.6 11.1 6.13 15.3 31.1 41.0 10.2 10.4 24.6 MAX 222 317 66 68 44 19 134 228 136 19 87 122 MIN 7.2 16 13 8.0 6.2 4.5 4.4 5.3 12 5.6 4.0 6.5 AC-FT 2470 5670 1600 838 618 377 910 1910 2440 628 642 1470 CFSM 2.12 5.04 1.38 .72 .59 .32 .81 1.65 2.17 .54 .55 1.30 IN. 2.45 5.63 1.59 .83 .61 .37 .90 1.90 2.42 .62 .64 1.45 CAL YR 1986 TOTAL 9512.1 MEAN 26.1 MAX 468 MIN 4.0 AC-FT 18870 CFSM 1.38 IN. 18.72 WTR YR 1987 TOTAL 9866.4 MEAN 27.0 MAX 317 MIN 4.0 AC-FT 19570 CFSM 1.43 IN. 19.42 RIO GUAYANILLA BASIN 234 50124700 RIO GUAYANILLA AT CENTRAL RUFINA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°0040, long 66°4649, at dirt road bridge, 0.7 ml (1.1 km) from mouth, 0.9 ml (1.4 km) east of Central Rufina and 0.9 mi (1.4 km) southeast of Guayanilla. DRAINAGE AREA.--22.8 sq ml (59.1 sq km). PERIOD OF RECORD.--Water years 1960-65, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARO WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 04... 1100 9.9 404 7.75 27.5 24 7.8 100 13 210000 96000 DEC 09... 1025 22 440 7.85 25.0 8.7 106 K1700 K640 FEB 1987 3... 1030 1.6 850 7.60 25.0 6.9 2.2 27 62 K1800 K13000 APR 07... 1050 29 333 7.70 26.0 1.5 7.4 92 19 K17000 4200 JUN 4... 1425 73 279 8.20 30.0 7.5 7.2 19 K7500 860 AUG 04.., 0830 3.0 771 7.40 28.0 20 0.2 72 280000 35000 HARD- ALKA- RARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- 015- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLQ SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS 504) AS CL) NOV 1986 04... 170 18 47 13 18 0.6 2.6 153 <0.5 41 19 DEC 09... 171 FEB 1987 3... 290 APR 07... 140 23 39 11 13 0.5 2.6 120 <0.5 30 15 JUN 4... 100 AUG 04... 280 7 76 21 46 1 4.0 270 55 51 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEM, GEN, GEM, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE N020403 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) S102) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 04... <0.1 18 250 6.71 35 0.78 0.02 0.80 0.58 0.22 DEC 09... 0.57 0.03 0.60 0.78 0.92 FEB 1987 3... 17 0.22 0.08 0.30 14.0 4.0 APR 07... 0.2 17 200 15.7 33 1.47 0.03 1.50 1.10 1.1 JUN 4... 27 1.28 0.02 1.30 0.25 0.75 AUG 04... 0.2 24 439 3.56 5 0.08 0.02 <0.10 7.90 8.1 K non-ideal count 235 RIO GUAYANILLA BASIN 50124700 RIO GUAYANILLA AT CENTRAL RUFINA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NITRO- NOV 1986 04... 0.8 1.6 0.16 1 <100 30 <1 <1 10 DEC 09... 1.7 2.3 10 0.22 FEB 1987 3... 18 18 81 2.40 APR 07... 2.2 3.7 16 0.37 1 100 30 <1 9 <10 JUN 1.0 2.3 0.22 4... AUq 04... 16 16 1.90 METHY- IFON, LEAD, NESE, MERCURY SILVER, ZINC, LENE tOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) MANGA- NOV 1986 04... 2100 9 100 <0.1 <1 <1 20 <0.01 2 0.07 DEC 09... FEB 1987 Q3... APR 07... 1400 13 70 <0.1 <1 <1 <10 <0.01 7 0.11 JUN 04... AUG 04... PESTICIDE ANALYSES CHLOR- DI- DI- ENDO- PCB, ALDRIN, DANE, ODD, DDE, DDT, AZINON, ELDRIN SULFAN, DATE TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 04... 1425 <0.1 <0.01 <0.1 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 HEPTA- METH- METHYL METHYL HEPTA- CHLOR MALA- OXY- PARA- TRI- ENDR1N, ETHION, CHLOR, EPDXIDE LINDANE THION, CHLOR, THION, THION, MIREX, DATE TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 04... <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 -0.01 <0.01 <0.01 <0.01 MPH- THA- LENES, PARA- POLY- PER- TOX- TOTAL THION, CHLOR. THANE APHENE, TRI- 2,4-D, 2,4,5-T 2, 4-DP SILVEX, DATE TOTAL TOTAL TOTAL TOTAL THION TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 04... <0.01 <0.1 <0.1 <1 <0.01 <0.01 <0.01 -.0.01 <0.01 RIO LOCO BASIN 236 50129700 RIO LOCO AT GUANICA, PR WATER-QUALITY RECORDS LOCATION.--Lat 17°5833, long 66°54'52, 0.6 mi (1.0 km) northwest of Guanica and 1.2 ml (1.9 km) northeast of Ensenada. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1975 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COL1- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- 1CAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER . (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) AlION) (MG/L) 100 ML) 100 ML) NOV 1986 04... 1330 E0.0 6000 7.50 28.5 2.3 2.6 33 38 2000 400 DEC 09... 1240 E140 279 7.75 25.5 8.8 118 2100 9600 FEB 1987 03... 1255 0.0 1000 7.50 26.0 7.0 6.0 74 19 5200 2400 APR 07... 1315 E5.0 672 7.60 27.0 8.0 4.5 57 23 3400 2900 JUN 02... 1125 0.0 418 7.80 28.5 3.5 5.5 71 <10 22000 K1600 AUG 06... 1400 E0.0 3146 7.60 29.0 20 2.0 35 K690 460 HARD- ALKA- RARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- D1S- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS 504) AS CL) NOV 1986 04... 539 319 60 93 810 15 28 221 <0.5 240 1400 DEC 09... 120 FEB 1987 03... - 140 APR 07... 200 0 38 25 64 2 2.5 200 <0.5 48 63 JUN 02... 200 AUG 06... 400 170 56 63 300 7 10 230 95 500 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONST1- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 04... 0.2 20 2800 5 0.36 0.04 0.40 0.18 0.42 DEC 1986 09... 0.59 0.21 0.80 0.82 1.3 FEB 1987 03... 14 <0.01 0.60 0.03 0.47 APR 07... 0.2 27 388 22 0.48 0.02 0.50 0.03 0.57 JUN 02... <1 0.48 0.02 0.50 0.18 0.02 AUG 06... 0.21 28 1200 2 0.19 0.01 0.20 0.05 0.55 K = non- ideal count E . estimate 237 RIO LOCO BASIN 50129700 RIO LOCO AT GUANICA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS El) AS CD) AS CR) AS CU) NOV 1986 04... 0.6 1.0 0.17 1 200 390 1 1 10 DEC 09... 2.1 2.9 13 0.41 FEB 1987 03... 0.5 1.1 4.9 0.05 APR 07... 0.6 1.1 4.9 0.15 2 100 130 <1 2 20 JUN 02... 0.2 0.7 0.12 AUG 06... 0.6 0.8 0.13 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE .RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) NOV 1986 04... 250 <5 50 <0.1 <1 1 20 <0.01 1 0.24 DEC 09... FEB 1987 03... APR 07... 770 <5 60 <0.1 <1 1 10 <0.01 4 0.05 JUN 02... AUG 06... PESTICIDE ANALYSES CHLOR- DI- DI- ENDO- PCB, ALDRIN, DANE, ODD, DOE, DDT, AZINON, ELDRIN SULFAN, DATE TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 02... 1125 <0.1 <0.01 <0.1 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 HEPTA- METH- METHYL METHYL HEPTA- CHLOR MALA- OXY- PARA- TRI- ENDRIN, ETHION, CHLOR, EPDXIDE LINDANE THION, CHLOR, THION, THION, MIREX, DATE TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 02... <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 NAPH- THA- LENES, PAPA- POLY- PER- TOT- TOTAL THION, CHLOR. THANE APHENE, TRI- 2,44, 2,4,5-T 2, 4-DP SILVEX, DATE TOTAL TOTAL TOTAL TOTAL THION TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 02... <0.01 <0.1 <0.1 <1 <0.01 <0.01 <0.01 <0.01 <0.01 238 THIS PAGE WAS LEFT BLANK INTENTIONALLY -N4firvIAYAGUEZ Rro YOgiiet basin jr-**\; ,...,.. • , ,..I ,/ , ' -- Grande de Aaosoo bosin rnJ , ,.." JO MARCAO Dr ainage boundary 1.00,0 v*Vd0 HORM1GU a A,Y.co basin e-r/onajibo rAjkAtg14 . 450, ROJO \ SAN GE ▪ RMAN ▪ GRAN°E sABAh14' Rib Loco ban CBAC Principe/ Lag.P' 143 for rages. EXPLANATION A1380 SURFACE-WATER STATION AND NUMBER „ QUALITY-OF-WATER STATION 1297 AND NUMBER 0143 WELL AN WELL NUMBER a-D r a na g e boundary Eaosto! boa SEA CARIBBEAN KILOMETERS LES Figure 23.--Rio Guanajibo basin. 240 LAGUNA JOYUDA BASIN 50130320 QUEBRADA MAMEY AT JOYUDA, PR LOCATION.--Lat 18°07'51", long 67°1009", Hydrologic Unit 21010003, 1.1 ml (1.8 km) northeast of Joyuda and 0.3 mi (0.5 km) upstream from Laguna Joyuda. DRAINAGE AREA.--0.38 mi2 (0.98 km 2 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--November 1985 to current year. GAGE.--Water-stage recorder. Elevation of gage is 5.77 ft (1.75 m) above mean sea level. REMARKS.--Records fair. EXTREMES FOR CURRENT PERIOD.--Peak discharges greater than base discharge of 12 ft'is (.340 03/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft3/s) (m)/s) (ft) (m) Date Time (ftVs) (10/s) (ft) (m) Oct. 8 1530 16 0.453 15.10 4.602 Nov. 27 1730 12 0.340 14.96 4.560 Oct. 22 0215 57 1.61 16.02 4.883 Dec. 25 2000 12 0.340 14.96 4.560 Oct. 26 1700 59 1.67 16.06 4.895 Apr. 12 1600 22 0.623 15.29 4.660 Nov. 12 0815 15 0.425 15.06 4.590 June 12 1615 19 0.538 15.20 4.633 Nov. 13 1445 60 1.70 16.07 4.898 July 2 1900 12 0.340 14.96 4.560 Nov. 14 1430 23 0.651 15.31 4.666 July 25 1600 28 0.793 15.44 4.706 Nov. 16 1700 44 1.25 15.79 4.813 Aug. 4 1415 41 1.16 15.72 4.791 Nov. 17 1730 35 0.991 15.60 4.755 Aug. 30 1645 23 0.651 15.30 4.663 Nov. 18 1715 *71 2.01 *16.25 4.953 Sept 22 1730 18 0.510 15.16 4.621 Nov. 25 1900 12 0.340 14.96 4.560 Sept 28 1430 38 1.08 15.66 4.773 No flow parts or all day Mar. 18-26, Apr. 26-30, May. 5-8, 30. 31. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .68 .35 .80 .21 .19 .18 .05 .02 .09 .03 .06 .09 2 .66 .29 .65 .19 .13 .27 .05 .03 .04 1.8 .05 .07 3 .25 .20 .58 .19 .11 .22 .04 .03 .04 .17 .05 .08 4 .23 .22 .51 .21 .10 .07 .04 .03 .05 .07 4.2 .07 5 .19 .27 .43 .23 .11 .06 1.2 .02 .83 .07 .26 .36 6 7 .16 .17 1.1 .34 .37 .41 .85 .25 .11 .10 .06 .06 .27 .12 .01 .o .06 .04 .07 1.1 .10 .08 .08 .04 8 1.9 .93 .41 .19 .10 .06 .08 .01 .03 .22 .13 .04 9 .29 1.5 .41 .22 .10 .06 .06 .02 .04 .11 .10 .05 10 .20 .57 .39 .18 .32 .06 .05 .03 .04 .08 .08 .06 11 .18 .39 .41 .20 .99 .04 .05 .03 .03 .07 .07 .06 12 .16 2.6 .41 .20 .36 .03 2.3 .03 2.0 .06 .08 .05 13 .41 5.2 .41 .20 .17 .02 .21 .03 .14 .06 .08 .04 14 .19 2.9 .42 .24 .13 .02 .14 .34 .06 .05 .07 .04 15 .15 .88 .50 .22 .11 .05 .13 .03 .05 .07 .11 .32 16 .13 4.2 .51 .19 .09 .02 .09 .02 .04 .06 .09 .06 17 .11 3.8 .46 .16 .08 .02 .06 .01 .04 .05 .07 .04 18 .11 5.9 .43 .15 .07 .01 .05 .01 05 .05 .08 .04 19 .17 2.6 .44 .14 .07 .01 .04 .08 .04 07 .10 .24 20 .13 1.6 .46 .13 .07 .01 .03 .02 .06 .08 .08 .06 21 .12 1.1 .44 .12 .08 .01 .03 .02 .05 .08 .07 1.1 22 5.2 1.1 .40 .11 .07 .01 .03 .01 2.0 .07 .06 3.7 23 .29 .97 .39 .11 .06 .01 .03 .01 .36 .06 .06 .59 24 .39 1.2 .36 .12 .05 .o .02 .01 .09 .06 .07 .13 25 .23 1.9 1.2 .10 .05 .01 .02 .02 .07 3.0 .12 .10 26 5.0 1.4 .39 .10 .06 .01 .01 .01 .05 .25 .10 .08 27 1.3 2.9 .27 .10 .09 .02 .01 .02 .04 .13 .08 .08 28 1.1 1.6 .27 .10 .12 .02 .01 .02 .05 .09 .07 4.6 29 .58 .88 .24 .12 --- .03 .01 .02 .05 .06 .08 .30 30 .53 .82 .23 .11 .03 .01 .01 .04 .14 2.8 .14 31 .43 --- .22 .13 .04 --- .04 --- .08 .17 --- TOTAL 21.64 49.71 13.82 5.77 4.09 1.52 5.24 0.99 6.57 8.36 9.62 12.71 MEAN .70 1.66 .45 .19 .15 .049 .17 .032 .22 .27 .31 .42 MAX 5.2 5.9 1.2 .85 .99 .27 2.3 .34 2.0 3.0 4.2 4.6 MIN .11 .20 .22 .10 .05 .00 .01 .00 .03 .03 .05 .04 AC-FT 43 99 27 11 8.1 3.0 10 2.0 13 17 19 25 CFSM 1.84 4.36 1.17 .49 .38 .13 .46 .08 .58 .71 .82 1.11 IN. 2.12 4.87 1.35 .56 .40 .15 .51 .10 .64 .82 .94 1.24 CAL YR 1986 TOTAL 165.57 MEAN .45 MAX 16 MIN .00 AC-FT 328 CFSM 1.19 IN. 16.21 WTR YR 1987 TOTAL 140.04 MEAN .38 MAX 5.9 MIN .00 AC-FT 278 CFSM 1.01 IN. 13.71 241 RIO GUANAJIBO BASIN 50133600 RIO GUANAJIBO NEAR SAN GERMAN, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°07'18", long 67°0356, at bridge on Highway 347, 2.2 ml (3.5 km) northwest of San German. DRAINAGE AREA.--45.5 sq mi (117.8 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER QUALITY DATA, WATER YEARS OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 06... 1220 33 436 7.70 26.5 8.7 6.4 81 <10 K11000 5000 DEC 11... 1335 50 556 7.75 26.0 6.4 79 5100 4400 FEB 1987 05... 1245 E5.0 682 7.35 27.0 3.9 1.7 22 31 K180000 38000 APR 09... 1410 17 552 7.50 29.0 2.5 4.8 63 12 2500 430 JUN 04... 1215 350 302 7.80 28.0 13 6.8 21 24000 6800 AUG 06... 1220 16 553 7.80 28.5 20 2.8 27 K11000 610 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FIT SULFIDE 015- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 06... 210 9 22 37 14 0.4 2.0 198 <0.5 19 17 DEC 11... 236 FEB 1987 5... 270 APR 09... 230 11 23 42 23 0.7 2.3 220 <0.5 29 22 JUN 04... 130 AUG 6... 180 7 28 26 13 0.4 2.5 170 15 13 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, 015- CONSTI- DIS- AT 105 GIN, GIN, GIN, GEN, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2tNO3 AMMONIA ORGANIC SOLVED (MG/L 015- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) S102) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 06... 0.2 34 264 23.5 31 0.54 0.06 0.60 0.14 0.3 DEC 11... 0.47 0.13 0.60 0.85 0.5 FEB 1987 5... 9 0.02 <0.10 4.80 APR 09... 0.5 35 309 14.0 16 0.52 0.18 0.70 1.40 0.5 JUN 04... 66 0.47 0.03 0.50 0.21 0.0 AUG 6... 0.2 30 230 9.94 5 0.84 0.06 0.90 0.30 0.7 K = non-ideal count E = estimate 3.3 242 RIO GUANAJIBO BASIN 50133600 RIO GUANAJIBO NEAR SAN GERMAN, PR--Continued WATER QUALITY DATA, WATER YEARS OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 06... 0.4 0.6 0.14 1 100 80 10 <1 10 DEC 11... 1.4 2.0 8.9 0.23 FEB 1987 5... 8.1 8.1 0.73 APR 09... 1.9 2.6 12 0.58 1 100 170 9 <10 <1 JUN 04... 0.2 0.7 0.22 AUG 6... 1.0 1.9 0.53 MANGA- METHY- IRON, LEAD, NEE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECO- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) NOV 1986 06... 1000 6 100 <0.1 <1 <1 20 <0.01 2 0.06 DEC 11... FEB 1987 5... APR 09... 610 20 140 <0.1 <1 <1 <10 <0.01 6 0.05 JUN 04... AUG 6... 243 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR LOCATION.--Lat 18°09'36, long 67°0508", at bridge on Highway 348, 0.5 ml (0.8 km) southwest of Rosario plaza. DRAINAGE AREA.--18.3 mi' (47.4 km 2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1985 to current year. GAGE.--Water-stage recorder. Elevation of gage is 50.0 ft (15.2 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. National Weather Service gage-height telemeter at station. EXTREMES FOR PERIOD OF RECORD.--Maximun discharge, 5,880 ft'is (166 e/s), Oct. 7, 1985, gage height, 12.67 ft (3.862 m), from floodmarks, from rating curve extended above 150 ft'/s (4.25 m'/s) on basis of step-backwater analysis; minimum discharge 7.8 ft'/s (0.221 10/s), Apr. 29, 1987. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 1,500 ft'is (42.5 m'/s) and maximun (k): Discharge Gage height Discharge Gage height Date Time (W/s) (m 3/s) (ft) (m) Date Time (W/s) (m 3/s) (ft) (m) Nov. 20 1930 2,350 66.6 9.03 2.752 Sept. 12 1415 *3,020 85.5 *9.91 3.020 June 18 1745 2,150 60.9 8.74 2.664 Sept. 15 1530 1,850 52.4 8.28 2.524 Aug. 18 1830 2,060 58.3 8.60 2.621 Minimum discharge recorded, 7.8 ft'/s (0.221 m7s), Apr. 29, but may have been less during period of no gage-height record Apr. 22-29. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES BAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 81 56 63 25 el9 e13 14 8.9 45 17 43 179 2 167 48 60 25 e22 e13 18 11 30 25 32 132 3 169 67 56 25 e19 e14 16 10 87 23 27 71 4 95 55 52 24 e18 e14 15 17 75 27 49 50 5 54 40 47 25 e17 e13 39 10 59 24 42 43 6 52 42 46 29 e16 e13 93 11 48 19 31 35 7 54 38 45 55 e16 e12 40 9.0 35 140 27 32 8 85 41 43 29 el5 e12 19 24 28 82 25 48 9 77 39 40 25 e14 e12 14 19 24 70 23 39 10 47 36 38 24 e14 el2 12 29 23 35 22 30 11 48 34 37 25 e28 e12 12 21 79 28 21 37 12 84 46 37 25 e66 13 21 138 54 25 25 222 13 84 70 36 23 e21 12 23 70 45 62 40 117 14 60 130 36 23 e28 12 21 29 29 38 26 76 15 68 107 34 22 e26 14 51 21 26 68 32 226 16 55 124 35 23 e20 16 45 19 25 37 25 104 17 43 178 40 21 e17 16 24 17 25 27 35 57 18 39 323 34 21 e17 13 16 18 182 37 169 43 19 79 248 33 20 e16 12 13 72 61 31 87 86 20 60 375 30 20 e15 12 11 57 34 56 40 68 21 42 244 30 20 e14 12 10 57 27 37 29 62 22 149 130 29 20 e14 12 e8.8 29 49 27 25 149 23 54 106 28 20 e14 12 e8.6 22 54 24 22 82 24 77 102 26 20 e14 11 e8.2 20 33 23 85 54 25 60 91 32 19 e14 13 e7.8 49 26 23 209 43 26 96 99 44 18 e13 11 e7.6 46 23 42 121 37 27 138 101 28 17 e14 11 e7.8 31 22 33 62 35 28 142 81 28 e18 e13 10 e8.0 28 21 42 51 48 29 111 66 37 e18 --- 10 e8.0 23 20 31 51 38 30 96 65 27 el8 11 11 20 18 97 237 31 31 69 --- 26 e19 10 --- 98 --- 72 129 --- TOTAL 2535 3182 1177 716 534 383 602.8 1033.9 1307 1322 1842 2274 MEAN 81.8 106 38.0 23.1 19.1 12.4 20.1 33.4 43.6 42.6 59.4 75.8 MAX 169 375 63 55 66 16 93 138 182 140 237 226 MIN 39 34 26 17 13 10 7.6 8.9 18 17 21 30 AC-FT 5030 6310 2330 1420 1060 760 1200 2050 Z590 2620 3650 4510 CAL YR 1986 TOTAL 18114.4 MEAN 49.6 MAX 500 MIN 9.4 AC-FT 35930 WTR YR 1987 TOTAL 16908.7 MEAN 46.3 MAX 375 MIN 7.6 AC-FT 33540 e Estimated __ -- RIO GUANAJIBO BASIN 244 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS 1979 TO CURRENT YEAR. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: OCTOBER 1985 TO SEPTEMBER 1986 INSTRUMENTATION.--US D-49 SEDIMENT SAMPLER SINCE OCTOBER 1985. AUTOMATIC SEDIMENT SAMPLER SINCE 1986 REMARKS.--sediment 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. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONS: Maximum daily mean, 8,150 mg/L October 7, 1985; Minimum daily mean, 2 mg/L several days. 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 CONCENTRATIONS: Maximum daily mean, 1,640 mg/L November 20, 1986; Minimum daily mean, 2.0 mg/L several days. SEDIMENT LOADS: Maximum daily, 4,700 tons (4,263 tonnes) September 12, 1987; Minimum daily 0.04 ton (0.04 tonne) several days. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 1u0 ML) NOV 1986 05... 1015 44 254 7.95 25.0 6.8 9.0 110 13 290 440 DEC 10... 1005 39 272 7.95 22.0 9.5 230 340 FEB 1987 04... 1025 18 270 7.85 22.0 3.6 9.8 113 <10 320 550 APR 08... 1010 20 234 8.10 24.5 2.0 8.4 102 14 K1300 2500 JUN 03... 1005 44 219 8.20 25.0 16 8.3 <10 K9200 4600 AUG 05... 0935 43 210 8.00 25.0 78 5.2 <10 23000 34000 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- UNITY CHLO- NESS NONCARB CALCIUM S1UM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TG1 FET SULFIDE DIS- DIS- (MG/L TOT FLO SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS 5) AS SO4) AS CL) NOV 1986 05... 120 3 23 16 7.5 0.3 1.3 120 <0.5 23 7.2 DEC 10... 121 FEB 1987 4... 130 APR 08... 110 0 20 14 7.5 0.3 1.3 110 <0.5 8.7 7.3 JUN 03... 99 AUG 5... 95 4 20 11 6.6 0.3 1.7 91 9.6 6.3 K = non-ideal count 245 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR--Continued WATER QUALITY DATA, WATER YEARS OCTOBER 1986 TO SEPTEMBER 1987 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONST1- DIS- AT 105 GEM, GEM, GEM, GEM, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C. NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 05... <0.1 30 180 21.4 10 0.69 0.01 0.70 0.01 0.20 DEC 10... <0.01 0.70 <0.01 FEB 1987 04... 9 <0.01 0.60 <0.01 - APR 08... 0.1 28 153 8.17 14 0.79 0.01 0.80 0.03 0.67 JUN 03... 35 0.49 0.01 0.50 0.03 0.17 AUG 05... 0.1 24 130 15.1 46 0.78 0.02 0.80 0.05 0.75 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 05... 0.2 0.9 0.04 <1 <100 <10 <1 <1 10 DEC 10... 0.5 1.2 5.3 0.04 - - FEB 1987 04... 0.4 1.0 4.4 0.03 APR 08... 0.7 1.5 6.6 0.06 <1 <100 <10 <1 7 <10 JUN 03... 0.2 0.7 0.05 -- AUG 05... 0.8 1.6 0.13 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) NOV 1986 05... 370 <5 30 <0.1 <1 1 20 <0.01 <1 0.04 DEC 10... FEB 1987 4... APR 08... 800 6 30 <0.1 <1 <1 20 ,0.01 5 0.02 JUN 03... AUG 5... 246 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR--Continued WATER QUALITY DATA, WATER YEARS OCTOBER 1986 TO SEPTEMBER 1987 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT SED. SED. SED. SEDI- SUSP. SUSP. SUSP. MENT, FALL FALL FALL STREAM- SEDI- DIS- DIAM. DIAM. DIAM. FLOW, MENT, CHARGE, PERCENT PERCENT PERCENT INSTAN- SUS- SUS- FINER FINER FINER DATE TIME TANEOUS PENDED PENDED THAN THAN THAN (CFS) (MG/L) (T/DAY) .002 MM .004 MM .008 MM OCT 1986 02... 1710 958 7200 18600 13 20 28 02... 1722 882 9000 21400 9 15 22 NOV 14... 1545 380 4080 4190 12 21 31 14... 1630 475 3190 4090 14 22 31 17... 2000 926 4510 11300 11 16 26 18... 1850 949 3730 9560 12 21 30 20.., 20... 1915 1930 1140 2370 2990 2660 9200 17000 11 19 20 26 31 37 20... 1945 2300 2580 16000 15 25 31 MAY 1987 12... 1715 869 5250 12300 12 23 31 12... 1745 788 6740 14300 10 19 27 12... 1800 716 5580 10800 6 17 25 12... 1815 643 4360 7570 13 23 34 12... 1845 528 3980 5670 13 20 33 12... 1930 394 5840 6210 16 26 34 12... 2000 341 4470 4120 10 27 41 12... 2015 311 3780 3170 12 26 38 12... 2145 220 1320 784 22 29 46 JUN 18.., 18... 1715 1730 506 1010 3960 1770 5410 4830 8 23 10 24 21 28 18... 1732 2080 8700 48900 12 18 27 18... 1745 2150 1440 8360 19 29 39 18... 1830 1060 6960 19900 14 25 34 18... 1845 944 1640 4200 24 25 45 18... 2030 364 1620 1590 27 34 40 18... 2045 327 1680 1480 23 30 47 18... 2145 230 3420 2120 30 48 70 SEP 01... 1900 1160 8560 26800 11 18 28 01... 1915 967 5260 13700 14 34 43 247 RIO GUANAJI80 BASIN 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR--Continued WATER QUALITY DATA, WATER YEARS OCTOBER 1986 TO SEPTEMBE9 1987 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT SED. SED. SED. SED. SED. SED. SED. SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. FALL FALL SIEVE SIEVE SIEVE SIEVE SIEVE DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. PERCENT PERCENT PERCENT PERCENT PERCENT PERCENT PERCENT FINER FINER FINER FINER FINER FINER FINER DATE THAN THAN THAN THAN THAN THAN THAN .016 MM .031 MM .062 MM .125 MM .250 MM .500 MM 1.00 MM OCT 1986 02... 38 52 67 71 78 83 88 02... 31 40 51 65 75 84 92 NOV 14... 44 62 76 87 96 99 99 14... 43 58 67 85 96 99 99 17... 38 56 58 73 93 98 99 18... 42 58 72 86 96 99 99 20... 47 61 75 88 98 99 99 20... 53 72 81 92 98 99 99 20... 49 63 77 89 98 99 99 MAY 1987 12... 42 58 75 89 98 99 99 12... 39 55 66 83 98 99 99 12... 31 48 67 82 95 99 99 12... 45 55 71 88 96 99 99 12... 45 58 79 90 98 99 99 12... 57 75 85 90 96 99 99 12... 59 75 86 94 98 99 99 12... 55 78 87 90 96 99 99 12... 70 84 89 96 99 99 100 JUN 18... 29 53 70 84 91 97 99 18... 62 80 84 96 98 99 99 18... 36 47 55 73 88 90 93 18... 51 74 83 96 98 99 99 18... 46 59 76 89 96 98 99 18... 65 72 88 96 99 99 99 18... 58 80 87 95 98 99 100 18... 60 78 82 98 99 100 100 18... 83 89 93 96 99 99 100 SEP 01... 38 48 63 77 91 97 99 01... 62 80 88 94 97 99 100 248 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORM1GUEROS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) OCTOBER NOVEMBER DECEMBER 1 81 175 100 56 18 2.7 63 4 .68 2 167 608 1040 48 15 1.9 60 3 .49 3 169 408 433 67 80 31 56 3 .45 4 95 155 40 55 100 15 52 2 .28 5 54 80 12 40 10 1.1 47 2 .25 6 52 61 16 42 20 2.3 46 2 .25 7 54 46 8.7 38 8 .82 45 4 .49 8 85 157 136 41 20 2.2 43 2 .23 9 77 80 21 39 8 .84 40 2 .22 10 47 20 2.5 36 5 .49 38 2 .21 11 48 20 2.6 34 5 .46 37 3 .30 12 84 163 87 46 30 3.7 37 3 .30 13 84 151 42 70 90 27 36 2 .19 14 60 58 9.4 130 234 167 36 2 .19 15 68 99 26 107 162 64 34 2 .18 16 55 70 10 124 252 163 35 2 .19 17 43 40 4.6 178 398 538 40 3 .39 18 39 25 2.6 323 998 1650 34 4 .37 19 79 215 151 248 346 321 33 4 .36 20 60 128 26 375 1640 3630 30 4 .32 21 42 45 5.1 244 143 147 30 4 .32 22 149 334 343 130 110 48 29 5 .39 23 54 30 4.4 106 70 25 28 6 .45 24 77 110 56 102 20 5 5 26 6 .42 25 60 73 17 91 56 16 32 21 6.8 26 96 208 139 99 80 21 44 20 2.4 27 138 309 182 101 129 47 28 6 .45 28 142 327 221 81 110 24 28 5 .38 29 111 70 21 66 25 4.5 37 20 2.0 30 96 20 5.2 65 7 1.2 27 11 .80 31 69 18 3.4 --- --- --- 26 4 .28 TOTAL 2535 3167.5 3182 6961.71 1177 21.03 249 RIO GUANAJ160 BASIN 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) JANUARY FEBRUARY MARCH 1 25 6 .41 19 5 .26 13 2 .07 2 25 7 .47 22 8 .48 13 13 .46 3 25 9 .61 19 5 .26 14 3 .11 4 24 10 .65 18 .24 14 11 .42 5 25 11 .74 17 4 .18 13 11 .39 6 29 28 3.7 16 4 .17 13 9 .32 7 55 49 11 16 4 .17 12 8 .26 8 29 6 .47 15 12 .49 12 10 .32 9 25 6 .41 14 11 .42 12 14 .45 10 24 7 .45 14 19 .72 12 12 .39 11 25 7 .47 28 33 2.5 12 13 .42 12 25 7 .47 66 85 15 13 11 .39 13 23 6 .37 21 7 .40 12 9 .29 14 23 6 .37 28 16 1.2 12 7 .23 15 22 6 .36 26 13 .91 14 6 .23 16 23 6 .37 20 56 3.0 16 4 .17 17 21 6 .34 17 8 .37 16 6 .26 18 21 6 .34 17 12 .55 13 7 .25 19 20 6 .32 16 5 .22 12 7 .23 20 20 6 .32 15 7 .28 12 8 .26 21 20 6 .32 14 3 .11 12 8 .26 22 20 6 .32 14 5 .19 12 7 .23 23 20 6 .32 14 4 .15 12 8 .26 24 20 5 .27 14 7 .26 11 8 .24 25 19 5 .26 14 7 .26 13 8 .28 26 18 4 .19 13 12 .42 11 8 .24 27 17 4 .18 14 3 .11 11 6 .18 28 18 4 .19 13 2 .07 10 6 .16 29 18 5 .24 --- --- --- 10 6 .16 30 18 5 .24 11 6 .18 31 19 5 .26 10 4 .11 TOTAL 716 25.43 534 29.39 383 8.22 250 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) APRIL MAY JUNE 1 14 4 .15 8.9 7 .17 45 30 3.6 2 18 4 .19 11 8 .24 30 20 1.6 3 16 4 .17 10 4 .11 87 110 68 4 15 4 .16 17 10 .46 75 350 71 5 39 44 9.4 10 7 .19 59 50 8.0 6 93 187 79 11 12 .36 48 50 6.5 7 40 40 4.3 9.0 16 .39 35 25 2.4 8 19 6 .31 24 32 5.0 28 18 1.4 9 14 2 .08 19 10 .51 24 12 .78 10 12 2 .06 29 15 1.2 23 10 .62 11 12 2 .06 21 9 .51 79 281 298 12 21 8 .45 138 870 1480 54 70 14 13 23 8 .50 70 100 19 45 50 6.1 14 21 7 .40 29 7 .55 29 16 1.3 15 51 52 9.5 21 4 .23 26 13 .91 16 45 15 1.8 19 4 .21 25 12 .81 17 24 3 .19 17 4 .18 25 12 .81 18 16 2 .09 18 4 .19 182 642 2180 19 13 2 .07 72 414 459 61 50 8.2 20 11 2 .06 57 135 55 34 15 1.4 21 10 2 .05 57 150 23 27 10 .73 22 8.8 2 .05 29 20 1.6 49 50 6.6 23 8.6 2 .05 22 15 .89 54 20 2.9 24 8.2 2 .04 20 5 .27 33 9 .80 25 7.8 2 .04 49 87 48 26 9 .63 26 7.6 2 .04 46 50 6.2 23 10 .62 27 7.8 2 .04 31 18 1.5 22 10 .59 28 8.0 2 .04 28 18 1.4 21 9 .51 29 8.0 8 .17 23 10 .62 20 5 .27 30 11 6 .18 20 10 .54 18 5 .24 31 --- --- --- 98 475 678 --- --- TOTAL 602.8 107.64 1033.9 2785.52 1307 2689.32 251 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR-Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY). WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) JULY AUGUST SEPTEMBER 1 17 5 .23 43 35 4.1 179 651 1580 2 25 10 .68 32 20 1.7 132 298 150 3 23 7 .43 27 12 .87 71 70 13 4 27 15 1.1 49 70 25 50 30 4.1 5 24 7 .45 42 35 4.0 43 15 1.7 6 19 10 .51 31 15 1.3 35 10 .95 7 140 640 1480 27 10 .73 32 10 .86 8 82 330 166 25 9 .61 48 40 5.2 9 70 90 17 23 5 .31 39 40 4.2 10 35 22 2.1 22 4 .24 30 10 .81 11 28 15 1.1 21 5 .28 37 30 3.0 12 25 12 .81 25 10 .68 222 1170 4700 13 62 131 125 40 15 1.6 117 208 90 14 38 20 2.1 26 10 .70 76 90 18 15 68 128 128 32 12 1.0 226 759 2700 16 37 40 4.0 25 15 1.0 164 120 34 17 27 20 1.5 35 20 1.9 57 60 9.2 18 37 50 5.0 169 312 724 43 30 3.5 19 31 25 2.1 87 100 23 86 246 246 20 56 88 66 40 30 3.2 68 139 47 21 37 12 1.2 29 15 1.2 62 101 25 22 27 12 .87 25 10 .68 149 445 646 23 24 20 1.3 22 9 .53 82 90 20 24 23 18 1.1 85 184 233 54 50 7.3 25 23 11 .68 209 681 1680 43 30 3.5 26 42 40 14 121 216 130 37 25 2.5 27 33 20 1.8 62 60 10 35 22 2.1 28 42 20 2.3 51 50 6.9 48 60 7.8 29 31 10 .84 51 55 7.6 38 30 3.1 30 97 218 258 237 716 1860 31 20 1.7 31 72 140 27 129 219 99 --- --- --- TOTAL 1322 2313.20 1842 4825.13 2274 10330.52 YEAR 16908.7 33264.61 RIO GUANAJIBO BASIN 252 50138000 RIO GUANAJIBO NEAR HORMIGUEROS, PR LOCATION.--Lat 18°0836", long 67°0857, Hydrologic Unit 21010003. at bridge on Highway 100, 1.4 ml (2.3 km) west of Hormigueros, and 2.0 ml (3.2 km) downstream from Rio Rosario. DRAINAGE AREA.--120 mi (311 km 2 ). WAIER-DISCHARGE RECORDS PERIOD OF RECORD.--Annual low-flow measurements 1959, monthly measurements April 1959 to November 1967. January 1973 to current year. GAGE.--Water-stage recorder. Datum of gage is at mean sea level. Previous to Nov. 7. 1980. at site 0.3 ml (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. National Weather Service gage-height telemeter at station. AVERAGE DISCHARGE.--14 years (1974-87), 216 ft 3 /s (6.117 40/s), 24.44 in/yr (621 mm/yr), 156,500 acre-ft/yr (193 he/yr): median of yearly mean discharges, 200 ft 3 /s (5.66 10/s), 145,000 acre-ft/yr (179 he/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 128,000 ft 3 /s (3,620 40/s), Sept. 16, 1975, gage height, 28.50 ft (8.687 m), site and datum then in use, from rating curve extended above 100 ft 3 /s (2.83 40/s) on the basis of contracted-opening measurement of peak flow; minimum discharge, 4.6 ft'/s (0.130 e/s), June 22, 1977. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 2,000 ft'is (56.6 m'/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft'/s) (40/s) (ft) (m) Date Time (ft'/s) (20/s) (ft) (m) Nov.18 0730 *3,410 96.6 *20.67 6.300 Nov.21 0545 2,390 67.7 19.50 5.944 Minimum discharge, 20 ft 3 /s (0.566 40/s), May. 8. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 172 224 344 86 46 29 e29 27 130 76 108 271 2 352 178 324 86 46 29 e37 28 301 79 76 312 3 459 164 300 88 41 29 e34 26 408 90 65 188 4 320 198 293 88 39 28 e32 30 629 69 106 136 5 186 145 261 89 37 27 e90 25 260 76 128 109 6 217 409 232 108 35 26 e350 23 216 61 81 99 7 158 312 217 165 34 26 e130 22 184 162 58 86 8 159 372 204 e94 33 26 e60 22 127 281 60 82 9 222 424 186 e89 32 25 e50 39 106 164 62 107 10 141 344 171 e84 32 25 42 108 101 94 51 78 11 141 251 157 e82 57 e26 39 176 111 75 48 81 12 154 466 145 e77 84 e27 72 190 151 66 93 214 13 194 414 134 e72 55 e25 70 283 128 66 e70 239 14 230 684 130 e72 139 e25 84 301 82 96 e62 186 15 192 e794 135 e70 93 e29 317 171 70 80 e74 384 16 172 1040 165 72 54 e33 295 83 64 79 e60 409 17 147 2620 161 69 45 e34 143 67 57 57 e84 177 18 136 2810 126 66 39 e30 96 152 128 56 e350 131 19 159 2270 126 64 37 e27 77 203 166 70 e300 218 20 171 1460 118 61 34 e27 67 142 100 69 153 193 21 138 1840 117 58 33 e26 58 166 90 94 106 249 22 505 816 109 57 34 e25 53 97 292 59 86 515 23 170 624 102 55 32 e25 48 91 336 52 74 835 24 280 532 99 56 31 e23 44 68 207 50 97 263 25 202 713 106 53 30 e27 39 66 158 111 266 194 26 263 647 132 51 30 e23 36 113 132 119 290 158 27 387 753 96 49 30 e23 32 87 114 86 138 139 28 559 769 92 48 30 e22 30 76 101 69 120 188 29 652 433 98 48 --- e22 28 58 93 71 184 157 30 507 369 87 49 e23 29 54 83 128 426 121 31 303 --- 85 48 e22 --- 134 --- 185 529 --- TOTAL 8048 23075 5052 2254 1262 814 2511 3128 5125 2890 4405 6519 MEAN 260 769 163 72.7 45.1 26.3 83.7 101 171 93.2 142 217 MAX 652 2810 344 165 139 34 350 301 629 281 529 835 MIN 136 145 85 48 30 22 28 22 57 50 48 78 AC-FT 15960 45770 10020 4470 2500 1610 4980 6200 10170 5730 8740 12930 CFSM 2.16 6.41 1.36 .61 .38 .22 .70 .84 1.42 .78 1.18 1.81 IN. 2.49 7.15 1,57 .70 .39 .25 .78 .97 1.59 .90 1.37 2.02 CAL YR 1986 TOTAL 74303.6 MEAN 204 MAX 4890 MIN 8.2 AC-FT 147400 CFSM 1.70 IN. 23.03 WTR YR 1987 TOTAL 65083 MEAN 178 MAX 2810 MIN 22 AC-FT 129100 CFSM 1.49 IN. 20.18 e Estimated RIO GUANAJIBO BASIN 253 50138000 RIO GUANAJIBO NEAR HORMIGUEROS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1958 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (f[R- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGh UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 06... 0925 138 399 7.75 24.5 28 6.5 79 14 21000 K820 DEC 11... 1015 161 440 7.65 24.0 -- 6.1 73 K9000 3500 FEB 1987 05... 1005 38 442 7.45 25.0 5.6 5.6 68 14 K9000 2000 APR 09... 1030 51 417 7.10 26.5 6.6 5.0 63 16 K86000 1(1300 JUN 04... 1005 588 321 7.50 25.0 150 7.0 31 K94000 52000 AUG 06... 0940 68 393 7.90 27.5 20 2.8 27 K79000 29000 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SLUM, WAT WH SULFATE RIDE, TOTAL WH WAT 015- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 06... 180 2 28 27 13 0.4 2.3 179 <0.5 16 15 DEC 11... 203 FEB 1987 5... 210 APR 09... 200 38 28 31 16 0.5 2.7 160 <0.5 21 16 JUN 04... - 220 AUG 6... 180 7 28 26 13 0.4 2.5 170 -- 15 13 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 06... 0.2 30 239 89.0 75 0.79 0.01 0.80 0.03 0.47 DEC 11... - 0.61 0.09 0.70 0.18 0.02 FEB 1987 5... -- 14 0.93 0.07 1.00 0.63 0.47 APR 09... 0.3 34 245 33.4 19 1.10 0.10 1.20 0.40 0.70 JUN 04... -- 314 0.93 0.07 1.00 0.07 0.38 AUG 6... 0.2 30 230 42.2 5 0.84 0.06 0.90 0.30 0.70 K non-ideal count 254 RIO GUANAJIBO BASIN 50138000 RIO GUANAJIBO NEAR HORMIGUEROS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEM, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 06... 0.5 0.85 0.22 <1 100 40 20 10 <1 DEC 11... 0.2 - 0.18 -- FEB 1987 05... 1.1 2.1 9.3 0.47 _ APR 09... 1.1 2.3 10 0.51 <100 30 <1 5 <10 <1 JUN 04... 0.6 1.6 0.40 -- AUG 06... 1.0 1.9 0.53 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL SLUE RECOV- RECOV- RECOV- PECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CM) (UG/L) (MG/L) NOV 1986 06... 3600 <5 220 <0.1 <1 <1 20 ,0.01 2 0.06 DEC 11... FEB 1987 5... APR 09... 900 <5 140 <0.1 <1 <1 <10 <0.01 4 0.07 JUN 04... AUG 6... PESTICIDE ANALYSES CHLOR- DI- DI- ENDO- PCB, ALDRIN, DANE, ODD, DDE, DDT, AZ1NON, ELDRIN SULFAN, DATE TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 04... 1005 <0.1 <0.01 <0.1 <0.01 <0.01 <0.01 0.02 <0.01 <0.01 HEPTA- METH- METHYL METHYL HEPTA- CHLOR MALA- OXY- PARA- TRI- ENDRIN, ETHION, CHLOR, EPDXIDE LINDANE THION. CHLOR, THION, THION, MIRE,, DATE TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 04... <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 NAPH- THA- LENES, PAPA- POLY- PER- TOX- TOTAL THION, CHLOR. THANE APHENE, TRI- 2,4-0, 2,4,5-T 2, 4-DP SILVEX, DATE TOTAL TOTAL TOTAL TOTAL THION TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 04... <0.01 <0.1 <0.1 <1 <0.01 Drainage boundary • / 53(o Culebrinos tosin GLARES .1 \\1 )/ ,b Grand fR,"i+ Guoicfoco / 44, sco Rio C °mut' bosin r N ......./..-- -, • \i ri i al I Fdo Tanarnd botin Law Ychlutro _ RAHIA DE MAYAGUEZ MAYAGUEZ MARICAC Coostai basin R(o io)ibo bosin Dra,nage bour:darY • Gunyanillo basin \and divide EXPLANATION A1440 SURFACE—WATER STATION AND NUMBER Y1388 QUALITY—OF—WATER STATION AND NUMBER 7 3 t. • *AIR CC71r C AOLV49. FAjAPFT?0-1'; °METERS 5 MILES Figure 24.--Rio Yaguez and Rio Grande de Anasco basins. 256 RIO YAGUEZ BASIN 50138800 RIO YAGUEZ NEAR MAYAGUEZ, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°1231, long 67°07'07, at steel-truss bridge on unnumbered paved road about 800 ft (244 m) south of Highway 106, 1.8 mi (2.9 km) west of Highways 106 and 352 junction, and 1.4 mi (2.3 km) east-northeast from Mayaguez plaza. DRAINAGE AREA.--6.7 sq mi (17.3 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- C1FIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- 1CAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 05... 1330 21 274 7.95 25.0 7.4 8.4 103 <10 K2400 2300 DEC 10... 1355 12 292 7.85 23.0 8.7 102 320 870 FEB 1987 04... 1350 7.1 267 8.00 27.0 2.9 10.1 128 <10 240 740 APR 08... 1355 2.3 294 8.20 26.0 0.8 8.6 107 12 590 880 JUN 03... 1350 2.7 226 8.40 29.5 2.2 8.8 <10 2100 2700 AUG 05... 1230 8.8 254 8.30 27.0 28 6.0 24 3300 4700 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATE RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLO SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS 5) AS SO4) AS CL) NOV 1986 05... 120 4 34 9.6 9.8 0.4 1.9 121 <0.5 7.3 8.7 DEC 10... -- 130 FEB 1987 4... 130 APR 08... 130 0 35 9.8 12 0.5 2.3 130 <0.5 10 10 JUN 03... -- 110 AUG 5... 110 4 30 9.4 9.9 0.4 2.4 110 8.1 7.9 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUE4TS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L 01S- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) 5IO2) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 05... <0.1 31 175 9.73 6 0.39 0.01 0.40 0.01 0.39 DEC 10... 0.89 0.01 0.90 0.01 0.19 FEB 1987 4... 6 n.59 0.01 0.60 0.01 0.69 APR 08... 0.1 31 188 1.17 3 0.49 0.01 0.50 0.01 0.49 JUN 03... 3 0.47 0.03 0.50 0.05 0.15 AUG 5... 0.1 28 160 3.80 3 0.59 0.01 0.60 0.03 0.77 K = non-ideal count 257 RIO YAGUEZ BASIN 50138800 RIO YAGUEZ NEAR MAYAGUEZ, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEN, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NITRO- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 05... 0.4 1.3 0.03 <1 <100 <10 <1 <1 10 DEC 10... 0.2 1.1 4.9 0.05 FEB 1987 4... 0.7 1.3 5.8 0.04 -- APR 08... 0.5 1.0 4.4 0.12 <1 100 10 <1 2 10 JUN 03... 0.2 0.7 0.05 AUG 5... 0.8 1.4 0.06 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TIDAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) NOV 1986 05... 600 5 30 <0.1 <1 <1 20 <0.01 3 0.05 DEC 10... FEB 1987 04.., APR 08... 320 8 30 <0.1 <1 <1 <10 <0.01 4 0.02 JUN 03... AUG 05... RIO GRANDE DE ANASCO BASIN 258 50143000 RIO GRANDE DE ARASCO NEAR LARES, PR WATER-QUALITY RECORDS LOCATION.--Lat 181526, long 665500, at bridge on Highway 124, 0.7 mi (1.1 km) downstream from confluence of Rio Blanco and Rio Prieto, and 3.7 mi (6.0 km) southwest of Lares plaza. DRAINAGE AREA.--26.3 sq mi (68.1 sq km) this does not include 36.2 sq mi (93.8 sq km) which contributes only dur- ing high floods, and 3.5 sq mi (9.1 sq km) which contributes only part of its storm runoff. PERIOD OF RECORD.--Water years 1959-68, 1970 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL. FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT (HIGH UM-MF (COLS. DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV 1986 05... 1050 42 312 7.80 25.5 7.7 8.7 109 51 K910 2100 DEC 11... 1255 39 326 8.30 24.0 10.8 130 K80 200 FEB 1987 5... 1250 19 343 8.50 26.0 0.4 9.7 122 <10 <10 530 APR 09... 1405 16 295 8.30 30.0 6.2 7.9 107 <10 100 230 JUN 11... 1225 28 300 8.60 29.0 1.2 8.4 111 <10 K91 K91 AUG 6... 1235 17 283 8.40 30.5 11 9.0 120 23 2300 K82 HARD- ALKA- HARD- NESS MAGNE- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM. WAT WH SULFATE RIDE. TOTAL WH WAT DIS- DIS- DIS- SORP- 01S- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) NOV 1986 05... 120 6 32 8.8 11 0.5 2.0 110 <0.5 20 9.4 DEC 11... -- 120 FEB 1987 5... - 120 -- APR 09... 120 11 33 9.3 13 0.5 1.8 110 -.0.5 22 11 JUN 11... -- 110 AUG 6... 130 19 35 10 14 0.5 1.7 110 23 10 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT 105 GEM, GEM, GEM, GEN, GEM, DIS- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) NOV 1986 05... <0.1 29 178 20.2 1 0.49 0.01 0.50 0.01 0.39 DEC 11... -- 0.99 0.01 1.00 <0.01 FEB 1987 5... _ 6 0.69 0.01 0.70 0.02 0.58 APR 09... 0.1 31 187 8.03 8 0.79 0.01 0.80 0.01 0.59 JUN 11... - <1 <0.01 0.80 0.02 1.3 AUG 6... 0.1 33 190 8.72 a 0.29 0.01 0.30 0.01 0.29 K non-ideal count 259 RIO GRANDE DE ANASCO BASIN 50143000 RIO GRANDE DE ANASCO NEAR LARES, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 NITRO- CHRO- GEN,AM- BARIUM, BORON, CADMIUM MIUM, COPPER, MONIA + NITRO- NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL ORGANIC GEN, GEM, PHOROUS ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE DATE (MG/L (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS N) AS N) AS NO3) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) NOV 1986 <1 <1 <1 <10 05... 0.4 0.9 0.04 <100 <10 DEC 11... <0.2 0.03 - FEB 1987 5... 0.6 1.3 5.8 0.04 APR 09... 0.6 1.4 6.2 0.05 <1 <100 20 <1 3 <10 JUN 11... 1.3 2.1 9.3 0.05 AUG 6... 0.3 0.6 0.03 MANGA- METHY- IRON, LEAD, NESE, MERCURY SILVER, ZINC, LENE TOTAL TOTAL TOTAL TOTAL SELE- TOTAL TOTAL BLUE RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- RECOV- CYANIDE ACTIVE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE ERABLE TOTAL PHENOLS SUB- DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (MG/L TOTAL STANCE AS FE) AS PB) AS MN) AS HG) AS SE) AS AG) AS ZN) AS CN) (UG/L) (MG/L) NOV 1986 05... 410 5 50 0.2 <1 ,1 20 ,0.01 3 0.03 DEC 11... FEB 1987 5... APR 09... 240 <5 30 <0.1 <1 <1 <10 <0.01 16 0.02 JUN 11... AUG 6... - 260 RIO GRANDE DE ANASCO BASIN 50144000 RIO GRANDE DE ANASCO NEAR SAN SEBASTIAN, PR LOCATION.--Lat 18°17'05", long 67°0305", Hydrologic Unit 21010003, on right bank, at downstream side of bridge on Highway 108, 0.4 ml (0.6 km) downstream from Quebrada La Zumbadora, 4.4 mi (7.1 km) northwest of Las Marias, 5.4 ml (8.7 km) southwest of San Sebastian. DRAINAGE AREA.--94.3 mi 2 (244.2 km 2), does not include 36.2 m1 2 (93.8 km') which contributes only during high floods, and 3.5 mi 2 (9.1 km 2 ) which contributes only part of its storm runoff. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1963 to current year. GAGE.--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, a site 600 ft (180 m) upstream at same datum. REMARKS.--Records fair. Transbasin diversion (except during floods) to Rio Yauco basin for hydroelectric power and irrigation above Lago Guayo, Yahuecas, and Prieto, combined usable storage 17,300 acre-ft (21.3 he). Limited storm runoff is contributed to basin by 3.5 m1 2 (9.1 km') above Rio Toro Diversion dam. AVERAGE DISCHARGE.--24 years (1964-87), 310 ft'/s (8.779 e/s), 44.64 in/yr (1,134 mm/yr), 224,600 acre-ft/yr (277 he/yr); median of yearly mean discharges, 302 ft'/s (8.55 e/s), 219,000 acre-ft/yr (270 he/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 140,000 ft'A (3,960 e/s), Sept. 16, 1975, gage height, 33.9 ft (10.33 m), from rating curve extended above 4,000 ft'/s (113 m'/s) on basis of slope-area measurement; minimum discharge, 31 ft'is (0.878 m'/s), Apr. 19, 20, 1965. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 6,000 ft'/s (170 e/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft'/s) (m3/s) (ft) (m) Date Time (W/s) (e/s) (ft) (m) Aug.18 1900 *5,950 168 *7.23 2.204 Minimum discharge, 58 ft'is (1.642 e/s), Mar. 28. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 91 364 640 153 120 88 64 292 422 121 207 444 2 226 321 485 150 119 86 64 279 729 113 139 421 3 343 471 326 148 106 86 64 123 764 123 147 249 4 205 367 300 146 103 88 63 138 403 131 245 205 5 170 283 282 142 102 88 101 93 451 163 210 257 6 203 263 267 167 100 86 198 80 443 113 128 135 7 477 282 260 234 99 83 266 79 244 110 111 407 8 690 249 255 160 96 83 107 117 177 213 102 210 9 456 232 245 157 93 80 79 134 152 266 97 329 10 216 223 240 141 96 80 67 334 146 139 91 277 11 363 213 233 135 217 79 107 329 341 122 89 400 12 321 257 225 132 415 77 272 561 201 118 94 546 13 667 287 220 139 175 74 187 515 152 130 179 781 14 603 243 222 141 213 72 242 246 121 155 467 436 15 291 275 216 135 201 84 361 144 183 130 543 480 16 223 437 207 129 124 83 343 105 184 165 336 446 17 196 1090 205 121 109 103 200 94 165 116 221 213 18 486 1780 199 118 102 81 130 114 339 205 961 188 19 524 1540 230 114 98 82 104 344 303 237 613 175 20 412 1080 202 115 95 76 92 275 160 178 195 230 21 239 879 196 112 94 72 85 453 150 225 132 417 22 289 555 187 110 97 76 79 200 223 137 106 313 23 265 457 179 110 95 68 77 143 236 134 107 350 24 303 400 173 114 91 62 72 122 189 141 126 250 25 416 382 173 109 91 69 69 447 145 114 181 220 26 843 489 170 107 90 66 66 234 127 327 197 203 27 1350 416 168 107 95 62 67 123 118 674 123 194 28 1610 379 173 109 94 60 66 115 263 361 104 302 29 868 351 192 118 --- 61 90 102 211 221 96 334 30 731 461 159 150 61 203 106 135 151 304 201 31 472 --- 154 134 61 --- 577 --- 182 569 --- TOTAL 14559 15026 7383 4157 3530 2377 3985 7018 7877 5715 7220 9613 MEAN 470 501 238 134 126 76.7 133 226 263 184 233 320 MAX 1610 1780 640 234 415 103 361 577 764 674 961 781 MIN 91 213 154 107 90 60 63 79 118 110 89 135 AC-FT 28880 29800 14640 8250 7000 4710 7900 13920 15620 11340 14320 19070 CFSM 4.98 5.31 2.53 1.42 1.34 .81 1.41 2.40 2.78 1.95 2.47 3.40 IN, 5.74 5.93 2.91 1.64 1.39 .94 1.57 2.77 3.11 2.25 2.85 3.79 CAL YR 1986 TOTAL 124577 MEAN 341 MAX 4170 MIN 45 AC-FT 247100 CFSM 3.62 IN. 49.14 WTR YR 1987 TOTAL 88460 MEAN 242 MAX 1780 MIN 60 AC-FT 175500 CFSM 2.57 IN. 34.90 261 RIO GRANDE DE ANASCO BASIN 50144000 RIO GRANDE DE ANASCO NEAR 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 1986 TO SEPTEMBER 1987 OXYGEN, COLI- STREP- SPE- DIS- FORM, TOCOCCI HARD- STREAM- CIFIC SOLVED FECAL, FECAL, NESS FLOW, CON- PH TEMPER- TUR- OXYGEN, (PER- 0.7 KF AGAR TOTAL INSTAN- DUCT- (STAND- ATURE BID- DIS- CENT UM-MF (COLS. (MG/L DATE TIME TANEOUS ANCE ARD WATER ITY SOLVED SATUR- (COLS./ PER AS (CFS) (US/CM) UNITS) (DEG C) (FTU) (MG/L) ATION) 100 ML) 100 ML) CAC03) NOV 1986 04... 1130 350 220 7.60 25.0 47 8.2 100 K6800 8600 87 JAN 1987 15... 1020 133 270 7.90 23.0 1.1 8.6 101 100 K150 110 APR 8... 1120 108 235 7.80 26.5 4.4 8.2 102 350 320 100 JUL 9... 1410 80 173 7.90 27.5 94 7.4 94 K7100 23000 74 HARD- ALKA- NESS MAGNE- POTAS- LINITY CHLO- FLUO- SILICA, NONCARB CALCIUM SIUM, SODIUM, SODIUM SIUM, WAT WH SULFATE RIDE, RIDE, DIS- WH WAT DIS- DIS- DIS- AD- DIS- TOT FET DIS- DIS- DIS- SOLVED TOT FLD SOLVED SOLVED SOLVED SORP- SOLVED FIELD SOLVED SOLVED SOLVED (MG/L DATE (MG/L AS (MG/L (MG/L (MG/L TION (MG/L MG/L AS (MG/L (MG/L (MG/L AS CAC03) AS CA) AS MG) AS NA) RATIO AS K) CAC03 AS SO4) AS CL) AS F) SI02) NOV 1986 04... 7 22 7.8 8.0 0.4 1.9 80 9.7 6.0 <0.1 28 JAN 1987 15... 0 27 9.6 9.5 0.4 1.3 110 11 8.0 0.1 30 APR 8... 6 25 9.0 8.5 0.4 1.8 89 9.2 7.4 0.1 28 JUL 9... 6 19 6.4 6.4 0.3 1.7 68 10 5.8 0.1 21 SOLIDS, SOLIDS, NITRO- NITRO- NITRO- NITRO- PHOS- PROS- RESIDUE SUM OF SOLIDS, GEN, GEN, GEN, GEN,AM- PHOS- PHOROUS PHATE, AT 180 CONSTI- DIS- NO2+NO3 AMMONIA AMMONIA MONIA + PHOS- PHOROUS ORTHO, ORTHO, DEG. C TUENTS, SOLVED DIS- DIS- DIS- ORGANIC PHOROUS DIS- OIS- D1S- 0I5- DIS- (TONS SOLVED SOLVED SOLVED TOTAL TOTAL SOLVED SOLVED SOLVED DATE SOLVED SOLVED PER (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L) (MG/L) DAY) AS N) AS N) AS NH4) AS N) AS P) AS P) AS P) AS PO4) NOV 1986 04... 130 136 123 0.96 0.03 0.04 1.3 0.05 0.12 0.13 0.4 JAN 1987 15... 159 167 57.1 0.84 0.06 0.08 0.2 0.06 0.04 0.03 0.09 APR 08... 146 151 42.6 1.10 0.04 0.05 0.5 0.05 0.05 0.03 0.09 JUL 09.., 117 110 23.8 0.94 0.08 0.1 0.3 0.16 0.03 0.03 0.09 ALUM- BERYL- CHRO- INUM, ARSENIC BARIUM, LIUM, CADMIUM MIUM, COBALT, :OPPER, IRON, LEAD, DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED DATE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS AL) AS AS) AS BA) AS BE) AS CD) AS CR) AS CO) AS CU) AS FE) AS PB) NOV 1986 04... 90 <1 35 <0.5 1 <1 <3 7 150 <5 JAN 1987 15... <10 <1 35 2 <1 <1 <3 2 6 <5 APR 08... 60 0 235 I crz 240 J F 1986 \N, MAMJJ ASONDJ FM AMJ J A S 1987 304 GROUND-WATER LEVELS RIO GRANDE DE MANATI BASIN 182634066262500. Local number, 209. LOCATION.--Lat 18°26'34", long 66°2625. Owner: P.R. Aqueduct and Sewer Authority. Name: Coto Norte No. 3. AQUIFER.--Aymamon-Aguada Limestone. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 16 in (0.41 m), cased 16 in (0.41 m) 0-495 ft (0-150.9 m), perforated 255-455 ft (77.7-138.7 m). Depth 495 FT (150.9 m). DATUM.--Elevation of land-surface datum is about 99.0 ft (30.2 m) above mean sea level, from topographic map. Measuring point: Hole on side of casing, 2.30 ft (0.70 m) above land-surface datum. REMARKS.--Abandoned observation well. Automatic recorder installed on September 11,1985 PERIOD OF RECORD.--October 1985 to September 1987. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 68.40 ft (20.84 m) below land-surface datum, Apr. 15, 1987; lowest water level recorded, 81.96 ft (24.98 m) below land-surface datum, June 24, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 80.32 80.25 79.48 80.59 80.99 80.15 80.58 74.23 78.88 80.01 80.34 2 80.33 80.28 79.55 80.61 80.97 80.19 80.59 74.41 78.92 80.02 80.37 3 80.33 80.31 79.63 80.62 80.96 80.27 80.64 74.58 78.98 79.55 80.40 4 80.34 80.32 79.70 80.65 80.96 80.29 80.66 74.75 79.02 79.62 80.43 5 80.35 80.31 79.77 80.61 80.98 80.35 80.70 - 74,92 78.99 79.50 80.46 6 80.36 79.85 79.84 80.62 80.98 80.40 80.71 75.10 79.08 79.53 80.50 7 80.38 79.73 79.89 80.62 81.03 80.45 80.75 75.27 79.15 79.56 80.53 8 80.38 78.69 79.94 80.64 81.03 80.50 80.78 75.44 78.98 79.60 80.56 9 80.40 78.84 79.98 80.69 81.05 80.56 80.82 75.61 79.13 79.63 80.59 10 80.40 78.99 80.01 80.72 81.06 80.61 80.85 75.78 79.17 79.66 80.62 11 80.41 78.94 80.06 80.78 79.76 80.65 79.17 75.95 79.22 79.69 80.65 12 80.41 --- 80.09 80.81 78.25 80.70 77.29 --- 76.13 79.26 79.72 80.68 13 80.42 78.90 80.15 80.82 78.36 80.71 70.27 78.29 76.30 79.31 79.75 80.71 14 80.42 79.08 80.19 80.85 78.55 80.71 69.32 78.29 76.48 79.38 79.78 80.74 15 80.42 79.13 80.21 80.85 78.67 80.40 --- 78.33 76.65 79.43 79.81 80.77 16 80.41 79.03 80.24 80.86 78.79 80.55 78.38 76.82 79.47 79.84 80.80 17 80.41 79.17 80.26 80.90 78.91 80.10 78.38 76.99 79.50 79.87 80.78 18 80.40 79.28 80.29 80.90 79.05 80.19 78.57 77.17 79.53 79.91 80.76 19 80.41 78.07 80.32 80.92 79.16 80.34 78.57 77.34 79.56 79.94 80.74 20 80.42 77.89 80.35 80.92 79.46 80.40 78.10 77.51 79.58 79.97 80.72 21 80.42 78.22 80.39 80.91 79.57 80.44 78.01 77.68 79.64 80.00 80.71 22 79.57 78.46 80.38 80.92 79.68 80.49 77.23 77.85 79.70 80.03 80.71 23 79.88 78.70 80.38 80.92 79.76 80.51 77.09 78.03 79.77 80.06 80.71 24 80.01 78.88 80.39 80.92 79.84 80.54 77.28 78.20 79.81 80.09 80.80 25 80.11 78.98 80.41 80.92 79.94 80.55 77.37 78.44 79.83 80.12 80.82 26 80.20 79.11 80.42 80.92 80.03 80.52 75.78 78.47 79.85 80.15 80.82 27 80.26 79.18 80.45 80.93 80.06 80.58 75.32 78.53 79.88 80.18 80.87 28 80.30 79.29 80.47 80.95 80.11 80.64 74.63 78.63 79.90 80.22 80.87 29 80.34 79.34 80.51 80.97 --- 80.68 74.20 78.77 79.93 80.25 80.90 30 80.32 79.39 80.52 80.97 80.71 73.85 78.83 79.96 80.28 80.91 31 80.26 --- 80.57 80.97 80.57 74,11 --- 79.99 80.31 --- LOW 80.42 80.57 80.97 81.06 80.71 78.83 79.99 80.31 80.91 HIGH 79.57 79.48 80.59 78.25 80.10 74.23 78.88 79.50 80.34 sm 65 • Let'lp -c170 LaJI ta; 75 La 80 - 1 0 IX .< LaJI: Z I- -I 85 J ASONDJ FM AMJJ AS 1987 ONDJ FM AMJ 1985 1986 305 GROUND-WATER LEVELS RIO GRANDE DE MANATI BASIN 182308066260400. Local number, 210. LOCAT1ON.--Lat 18°23'08", long 66°2604". Owner: Gelo Martinez. Name: Gelo Martinez well. AQUIFER.--Lares Limestone. 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 point: Hole on side of casing, 2.00 ft (0.61 m) above land-surface datum. REMARKS.--Abandoned observation well. Automatic recorder installed on February 27,1986. PERIOD OF RECORD.--October 1985 to September 1987. 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, 67.67 ft (20.62 m) below land-surface datum, Apr. 6, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 64.14 65.21 51.73 54.70 61.78 52.57 55.70 48.44 47.86 49.18 49.68 56.66 2 64.26 65.18 50.92 54.89 62.81 52.77 55.95 48.67 47.71 49.18 49.68 57.24 3 64.40 64.96 51.04 55.09 62.84 52.97 56.16 48.80 47.53 49.18 49.69 57.76 4 64.55 64.79 51.12 55.31 62.86 53.16 56.32 48.92 47.36 49.19 49.77 58.28 5 64.55 64.66 51.16 55.60 62.88 53.39 56.49 48.96 47.31 49.19 49.71 58.78 6 64.58 64.57 51.21 56.03 62.90 53.66 56.64 48.98 47.30 49.19 49.60 58.93 7 64.68 62.70 51.24 56.63 62.91 53.95 56.71 49.00 47.26 49.19 49.59 58.73 8 64.59 56.35 51.28 57.27 62.95 54.23 56.80 49.04 47.22 49.19 49.65 58.65 9 64.57 49.58 51.29 57.65 62.98 54.54 56.98 49.03 47.22 49.19 49.72 58.84 10 64.58 49.26 51.31 56.01 63.04 54.88 57.18 49.04 47.27 49.20 49.79 59.01 11 64.67 49.12 51.36 58.36 62.99 55.25 57.31 49.04 47.41 49.22 49.85 59.31 12 64.77 49.06 51.08 58.68 61.34 55.59 56.88 49.18 47.57 49.25 49.91 59.64 13 64.86 49.00 51.67 59.06 49.41 55.89 49.82 49.19 47.69 49.30 50.23 59.85 14 64.91 48.81 51.77 59.41 48.69 56.18 47.88 49.18 47.79 49.33 51.00 60.02 15 64.98 49.00 51.83 59.66 48.94 56.49 47.63 49.18 48.02 49.36 52.27 60.22 16 65.05 49.12 51.88 59.73 49.18 56.59 47.35 49.18 48.39 49.39 53.44 60.17 17 65.09 49.19 51.97 60.00 49.45 56.59 47.15 49.18 48.70 49.40 54.45 60.38 18 65.15 49.52 52.10 60.26 49.76 55.92 47.07 49.18 48.87 49.41 55.28 60.57 19 65.19 49.76 52.26 60.48 49.96 54.18 47.08 49.18 48.96 49.45 55.86 60.87 20 65.22 49.55 52.46 60.67 50.15 53.20 47.09 49.18 49.06 49.46 56.08 60.93 21 65.31 49.31 52.68 60.87 50.31 53.11 47.10 49.13 49.09 49.51 56.25 60.35 22 65.30 49.38 52.90 61.08 50.53 53.25 47.10 48.86 49.11 49.52 56.25 59.55 23 65.18 49.61 53.12 61.25 50.70 53.48 47.14 48.54 49.07 49.54 56.20 58.68 24 64.99 49.84 53.30 61.37 50.95 53.73 47.19 48.60 49.09 49.58 56.27 57.75 25 64.95 50.05 53.47 61.45 51.32 54.06 47.26 48.81 49.12 49.60 56.42 57.15 26 64.98 50.30 53.62 61.51 51.72 54.32 47.40 48.79 49.14 49.62 5b.94 56.88 27 65.07 50.55 53.86 61.57 52.03 54.54 47.52 48.73 49.15 49.63 54.58 56.74 28 65.20 50.80 54.00 61.61 52.29 54.79 47.62 48.70 49.15 49.64 54.15 56.74 29 65.32 51.08 54.12 61.68 54.99 47.77 48.52 49.15 49.65 54.72 56.88 30 65.33 51.39 54.25 61.72 55.22 48.07 48.28 49.18 49.66 55.41 57.16 31 65.27 54.45 61.75 55.47 48.09 49.69 56.04 LOW 65.33 65.21 54.45 61.75 63.04 56.59 57.31 49.19 49.18 49.69 56.42 60.93 HIGH 64.14 48.81 50.92 54.70 48.69 52.57 47.07 48.09 47.22 49.18 49.59 56.66 WTR YR 1987 MEAN 54.09 LOW 65.33 HIGH 47.07 E 20 cn 0 w 40 0 zitt td (I) 60 z < 80 FM JASON OND J FM AMJ J AS 1986 1987 306 GROUND-WATER LEVELS RIO CIBUCO BASIN 182647066201700. Local number, 70. LOCATION.--Lat 18°26'47", long 66°2017". Owner: P.R. Aqueduct and Sewer Authority. Name: Sabana Hoyos. AQUIFER.--Limestone of Tertiary Age. WELL 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 point: Top of casing wooden cover, 1.30 ft (0.40 m) above land-surface datum. REMARKS.--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 1986 TO SEPTEMBER 1987 INSTANMTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 28.44 28.50 27.84 28.30 28.74 28.42 28.28 26.23 25.83 26.18 26.62 26.99 2 28.45 28.50 27.86 28.32 28.74 28.43 28.30 26.31 25.86 26.18 26.63 26.98 3 28.47 28.49 27.88 28.33 28.74 28.43 28.33 26.37 25.86 26.18 26.63 26.97 4 28.48 28.49 27.90 28.35 28.75 28.44 28.35 26.42 25.84 26.18 26.63 26.97 5 28.49 28.48 27.92 28.35 28.76 28.46 28.38 26.48 25.84 26.19 26.63 26.97 6 28.51 28.44 27.95 28.36 28.77 28.48 28.40 26.53 25.87 26.20 26.64 26.98 7 28.52 28.36 27.97 28.37 28.78 28.50 28.42 26.58 25.88 26.20 26.65 26.98 8 28.54 28.29 27.98 28.38 28.79 28.52 28.45 26.62 25.90 26.22 26.66 26.99 9 28.54 28.16 27.99 28.40 28.80 28.54 28.47 26.65 25.94 26.23 26.66 27.01 10 28.56 28.07 28.02 28.42 28.81 28.56 28.48 26.69 25.97 26.22 26.68 27.00 11 28.57 27.99 28.04 28.44 28.75 28.57 28.50 26.72 26.00 26.25 26.70 26.99 12 28.57 27.95 28.06 28.47 28.70 28.59 28.04 26.76 26.05 26.26 26.71 27.01 13 28.58 27.90 28.08 28.49 28.56 28.61 26.23 26.79 26.08 26.27 26.73 26.99 14 28.59 27.86 28.10 28.51 28.46 28.62 25.25 26.82 26.11 26.30 26.74 26.98 15 28.58 27.83 28.12 28.52 28.39 28.62 24.70 26.86 26.14 26.33 26.76 26.97 16 28.57 27.80 28.13 28.54 28.35 28.58 24.47 26.90 26.17 26.35 26.78 26.96 17 28.56 27.79 28.15 28.55 28.33 28.47 24.52 26.93 26.19 26.36 26.80 26.97 18 28.56 27.78 28.16 28.57 28.32 28.32 24.70 26.96 26.22 26.38 26.82 26.97 19 28.56 27.77 28.17 28.58 28.32 28.23 24.92 26.98 26.19 26.40 26.83 26.98 20 28.56 27.76 28.19 28.59 28.33 28.18 25.09 26.95 26.18 26.42 26.84 26.99 21 28.56 27.75 28.20 28.58 28.33 28.16 25.24 26.87 26.18 26.42 26.86 27.00 22 28.54 27.75 28.21 28.58 28.34 28.15 25.37 26.60 26.17 26.45 26.86 27.01 23 28.52 27.76 28.23 28.59 28.35 28.14 25.50 26.41 26.15 26.47 26.89 27.02 24 28.51 27.77 28.25 28.61 28.37 28.14 25.61 26.34 26.12 26.50 26.90 27.04 25 28.50 27.78 28.26 28.63 28.38 28.15 25.72 26.34 26.12 26.53 26.93 27.08 26 28.50 27.80 28.25 28.65 28.40 28.16 25.82 25.84 26.13 26.55 26.93 27.11 27 28.50 27.81 28.24 28.66 28.41 28.19 25.90 25.74 26.16 26.57 26.94 27.13 28 28.50 27.82 28.25 28.70 28.42 28.22 25.99 25.71 26.18 26.58 26.95 27.15 29 28.50 27.82 28.25 28.72 28.24 26.08 25.73 26.18 26.59 26.97 27.17 30 28.50 27.83 28.26 28.73 28.26 26.16 25.76 26.18 26.60 26.99 27.19 31 28.50 28.28 28.72 28.27 25.80 26.61 27.01 LOW 28.59 28.50 28.28 28.73 28.81 28.62 28.50 26.98 26.22 26.61 27.01 27.19 HIGH 28.44 27.75 27.84 28.30 28.32 28.14 24.47 25.71 25.83 26.18 26.62 26.96 WTR YR 1987 MEAN 27.4 LOW 28.81 HIGH 24.47 20 24 z< _ex Lai>u) 28 32 ONDJFMAMJJ ASONDJFMAMJJ ASONDJFMAMJJ AS 1984 1985 1986 1987 307 GROUND-WATER LEVELS RIO CIBUCO BASIN 182615066235300. Local number, 211. LOCATION.--Lat 18°26'15", long 66°2353'. Owner: P.R. Aqueduct and Sewer Authority. Name: Rosario No. 2. AQUIFER.--Aguada Limestone. WELL CHARACTERISTICS,--Drilled unused water-table well, diameter 14 in (0.36 m) 0-200 ft (0-61.0 m). diameter 12 in (0.30 m) 200-250 ft (61.0-76.2 m), cased 12 in (0.30 m) 0-250 ft (0-76.2 m), 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 m). Depth 270 ft (82.3 m). DATUM.--Elevation of land-surface datum is about 215 ft (65.5 m) above mean sea level, from topographic map. Measuring point: Hole on side of casing, 1.15 ft (0.35 m) above land-surface datum. REMARKS.--Abandoned observation well. Automatic recorder installed on September 17,1985. PERIOD OF RECORD.--October 1985 to September 1987. 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. 193.10 ft (58.86 m) below land-surface datum, Mar. 21, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 192.71 192.65 192.37 192.82 192.95 192.90 192.85 191.78 191.77 192.07 192.23 2 192.71 192.66 192.41 192.83 192.95 192.90 192.87 191.84 191.78 192.07 192.23 3 192.71 192.67 192.48 192.83 192.96 192.90 192.89 191.88 191.78 192.07 192.24 4 192.71 192.67 192.51 192.83 192.96 192.91 192.91 191.89 191.79 192.08 192.24 5 192.71 192.67 192.55 192.83 192.94 192.91 192.94 191.90 191.79 192.08 192.24 6 192.70 192.67 192.57 192.82 192.94 192.94 192.96 191.94 191.80 192.09 192.25 7 192,70 192.65 192.57 192.81 192.93 192.94 192.98 191.96 191.80 192.09 192.25 8 192.70 192.60 192.57 192.80 192.94 192.97 193.00 191.99 191.83 192.09 192.25 9 192.70 192.47 192.57 192.82 192.94 193.00 193.01 192.00 191.83 192.10 192.26 10 192.70 192.44 192.58 192.89 192.95 193.00 193.01 192.02 191.83 192.10 192.26 11 192.70 192.36 192.61 192.93 192.87 192.99 192.99 192.07 191.83 192.10 192.26 12 192.70 192.31 192.62 192.96 192.59 192.99 192.67 192.10 191.83 192.11 192.26 13 192.70 192.31 192.66 192.98 192.38 192.98 191.36 192.13 191.83 192.11 192.27 14 192.70 192.30 192.67 192.98 192.33 192.97 190.96 192.16 191.85 192.12 192.21 15 192.70 192.29 192.67 192.98 192.32 192.97 190.91 192.18 191.87 192.12 192.28 16 192.70 192.29 192.70 192.98 192.32 192.94 190.87 192.23 191.87 192.12 192.38 17 192.69 192.28 192.70 192.98 192.32 192.91 190.90 192.25 !91.87 192.13 192.37 18 192.69 192.27 192.72 192.98 192.62 192.83 190.93 192.26 191.87 192.13 192.37 19 192.69 192.27 192.74 192.97 192.64 192.81 190.96 192.26 191.89 192.13 192.37 20 192.69 192.26 192.75 192.97 192.68 192.81 190.99 192.26 191.90 192.14 192.36 21 192.69 192.26 192.75 192.96 192.71 192.81 191.00 192.25 --- 191.92 192.16 192.36 22 192.69 192.26 192.75 192.94 192.76 192.81 191.14 192.06 --- 191.96 192.18 192.35 23 192.63 192.30 192.74 192.93 192.79 192.82 191.21 191.98 --- 191.97 192.19 192.35 24 192.62 192.32 192.74 192.93 192.84 192.82 191.34 191.92 --- 191.98 192.20 192.34 25 192.61 192.32 192.74 192.93 192.86 192.82 191.42 191.92 191.68 191.99 192.20 192.34 26 192.61 192.32 192.74 192.93 192.88 192.84 191.51 191.65 191.68 191.99 192.20 192.33 27 192.62 192.32 192.74 192.93 192.89 192.85 191.56 191.46 191.68 191.99 192.21 192.34 28 192.63 192.33 192.75 192.94 192.89 192.87 191.61 191.42 191.72 192.05 192.21 192.36 29 192.64 192.34 192.76 192.94 192.88 191.68 191.73 192.06 192.21 192.36 30 192.65 192.35 192.78 192.94 192.89 191.73 191.75 192.06 192.22 192.36 31 192.65 192.81 192.95 192.85 192.06 192.23 LOW 192.71 192.57 192.81 192.98 192.96 193.00 193.01 192.06 192.23 192.38 HIGH 192.61 192.26 192.37 192.80 192.32 192.81 190.87 191.77 192.07 192.21 ONDJFMAMJJ ASONDJFMAMJJ AS 1985 1986 1987 308 GROUND-WATER LEVELS RIO CIBUCO BASIN 182515066194000. Local number, 212. LOCATION.--Lat 18'25'15", long 66°19'40. Owner: U.S. Geological Survey. Name: Ponderosa 1W-1. AQUIFER.--Aguada Limestone-Cibao Formation. WELL 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 point: Shelter floor on top of 4 in (0.10 m) casing, 3.00 ft (0.91 m) above land-surface datum. REMARKS.--Observation well. Automatic recorder installed on October 17, 1985. PERIOD OF RECORD.--October 1985 to September 1987. 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 73.77 73.10 72.20 71.28 70.58 70.10 69.46 65.93 64.62 64.01 64.59 65.32 2 73.83 73.13 72.41 71.31 70.36 70.06 69.71 65.85 64.54 63.98 64.59 65.25 3 73.87 73.16 72.30 71.36 70.21 70.04 69.89 65.79 64.57 63.93 64.57 65.20 4 73.90 73.16 72.34 71.38 70.29 70.32 69.79 65.73 64.43 63.88 64.56 65.22 5 73.62 73.16 72.03 71.36 70.34 70.51 69.72 65.72 64.25 63.86 64.64 65.29 6 74.07 73.16 71.88 71.12 70.31 70.42 69.65 65.93 64.14 63.83 64.59 65.37 7 74.15 73.05 71.77 71.00 70.33 70.35 69.87 66.11 64.00 63.79 64.56 65.42 8 74.22 72.91 71.77 70.95 70.38 70.27 70.06 66.27 63.90 63.98 64.54 65.49 9 74.31 72.67 71.81 71.02 70.41 70.20 70.20 66.19 63.84 64.15 64.54 65.55 10 74.36 72.49 71.56 71.12 70.49 70.15 70.08 66.14 63.94 64.51 64.56 65.60 11 74.12 72.33 71.50 71.20 70.75 70.15 69.98 66.20 64.05 64.37 64.81 65.64 12 73.96 72.24 71.44 71.27 70.55 70.46 69.73 66.19 64.15 64.32 65.01 65.70 13 73.85 72.14 71.44 71.36 70.26 70.66 68.74 66.42 64.05 64.31 65.18 65.75 14 73.73 72.23 71.42 71.70 70.06 70.51 68.04 66.60 63.95 64.21 65.33 65.79 15 73.91 72.26 71.40 71.73 69.92 70.44 67.59 66.74 63.88 64.46 65.26 65.82 16 74.09 72.23 71.38 71.72 69.79 70.36 67.19 66.64 63.83 64.58 65.21 65.95 17 74.21 72.21 71.37 71.72 69.73 70.27 66.86 66.59 63.95 64.70 65.20 65.99 18 74.31 72.19 71.36 71.72 69.95 70.09 66.40 66.54 64.07 64.65 65.18 66.03 19 74.40 72.33 71.36 71.72 70.07 70.23 66.09 66.53 64.16 64.60 65.19 66.08 20 74.46 72.33 71.36 70.66 70.18 70.30 65.84 66.51 64.06 64.57 65.20 66.09 21 74.52 72.33 71.36 70.78 69.98 70.08 65.69 66.67 63.94 64.46 65.23 66.11 22 74.54 72.33 71.36 70.66 69.88 69.94 65.77 66.58 63.87 64.62 65.25 66.15 23 74.58 72.33 71.36 70.57 69.79 69.84 65.64 66.24 63.78 64.83 65.27 66.17 24 74.59 72.34 71.37 70.54 69.74 69.75 65.53 66.02 63.91 64.94 65.31 66.22 25 74.54 72.25 71.40 70.50 69.97 69.70 65.46 65.85 64.02 64.97 65.28 66.25 26 74.61 72.16 71.40 70.49 70.18 69.92 65.43 65.55 64.12 64.88 65.22 66.29 27 74.62 72.03 71.41 70.47 70.a3 70.06 65.38 65.47 64.05 64.81 65.20 66.33 28 73.49 72.23 71.41 70.78 70.19 69.93 65.36 65.37 63.97 64.73 65.26 66.36 29 73.00 72.18 71.42 70.75 --- 69.83 65.59 65.08 63.91 64.66 65.29 66.38 30 73.26 72.21 71.43 70.69 69.75 65.78 64.89 63.86 64.64 65.34 66.40 31 73.14 --- 71.29 70.61 69.49 --- 64.76 --- 64.61 65.37 --- LOW 74.62 73.16 72.41 71.73 70.75 70.66 70.20 66.74 64.62 64.97 65.37 66.40 HIGH 73.00 72.03 71.29 70.47 69.73 69.49 65.36 64.76 63.78 63.79 64.54 65.20 WTR YR 1987 MEAN 68.5 LOW 74.62 HIGH 63.78 ONDJ FMAMJJ ALSONDJ FM AMJJ AS 1985 1986 1987 309 GROUND-WATER LEVELS RIO CIBUCO BASIN 182330066185700. Local number, 213. LOCATION.--Lat 18°2330, long 66'18'57". Owner: P.R. Aqueduct and Sewer Authority. Name: 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 point: Hole on side of casing, 2.95 ft (0.90 m) above land-surface datum. REMARKS.--Abandoned observation well. Automatic recorder installed on September 16, 1985. PERIOD OF RECORD.--October 1985 to September 1987. 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, 49.55 ft (15.10 m) below land-surface datum, May 1, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 47.11 48.38 45.60 46.10 46.75 46.01 37.70 35.37 33.35 36.72 38.97 2 47.11 48.34 45.59 46.15 46.67 46.06 37.96 35.02 33.48 36.83 39.10 3 47.15 48.32 45.58 46.24 46.57 46.13 37.52 34.34 33.59 36.94 39.24 4 47.21 48.29 45.56 46.24 46.56 46.13 37.56 34.10 33.69 37.03 39.28 5 47.25 48.25 45.52 46.20 46.52 46.15 37.67 33.97 33.78 37.06 39.41 6 47.27 48.24 45.50 46.14 46.48 46.20 37.81 33.75 33.91 37.07 39.60 7 47.34 48.29 45.49 46.29 46.48 46.26 37.96 33.70 34.03 36.95 39.68 8 47.38 48.00 45.49 46.52 46.30 38.12 33.54 34.13 36.83 39.87 9 47.37 47.98 45.49 46.51 46.32 38.30 33.39 34.24 36.81 40.00 10 47.39 47.86 45.50 46.51 46.36 38.46 33.18 34.35 36.86 40.14 11 47.48 47.77 45.49 46.51 46.48 38.65 33.09 34.46 36.91 40.25 12 47.56 47.73 45.49 46.50 46.30 38.74 33.01 34.56 36.83 39.98 13 47.60 47.60 45.51 46.51 44.81 38.77 32.96 34.67 36.85 39.91 14 47.65 47.47 45.54 46.49 43.56 38.77 32.90 34.79 36.99 39.90 15 47.72 47.38 45.28 46.49 42.45 39.04 32.87 34.90 37.05 39.95 16 47.75 47.29 45.49 46.54 41.41 39.16 32.83 35.00 37.13 40.02 17 47.78 47.16 45.53 46.59 40.64 39.31 32.71 35.11 37.17 40.04 18 47.80 47.03 45.57 46.61 39.99 39.40 32.35 35.22 37.23 40.11 19 47.86 46.80 45.60 46.61 39.58 39.44 32.35 35.33 37.35 40.21 20 47.87 46.57 45.62 46.63 39.14 39.50 32.81 35.43 37.53 40.38 21 47.92 46.38 45.65 46.68 38.80 39.38 32.86 35.54 37.83 40.40 22 48.00 46.21 45.68 46.75 38.51 39.01 32.99 35.65 37.95 40.52 23 48.03 46.08 45.73 46.77 38.29 38.66 32.91 35.75 38.09 40.63 24 48.03 45.85 45.76 46.77 38.12 38.58 32.97 35.86 38.27 40.66 25 48.06 45.86 45.80 46.87 38.00 37.71 32.99 35.97 38.41 40.71 26 48.12 45.79 45.80 46.91 37.85 37.40 33.00 36.08 38.50 40.76 27 48.16 45.75 45.85 46.91 37.73 36.86 33.01 36.18 38.59 40.84 28 48.19 45.73 45.94 46.70 37.71 36.45 33.04 36.29 38.64 40.86 29 48.24 45.65 46.00 46.54 37.73 36.04 33.05 36.40 38.66 40.85 30 48.26 45.63 46.02 46.38 37.73 35.71 33.16 36.51 38.75 40.90 31 48.36 46.05 46.02 35.49 36.61 39.00 LOW 48.36 48.38 46.05 46.91 46.48 39.50 35.37 36.61 39.00 40.90 HIGH 47.11 45.63 45.28 46.02 37.71 35.49 32.35 33.35 36.72 38.97 25 La L'a Law 35 zit( _rg v,) 45 crz .4 55 ONDJFMAMJJASONDJFMAMJJAS 1985 1986 1987 310 GROUND-WATER LEVELS RIO DE LA PLATA BASIN 182746066170800. Local number, 214. LOCATION.--Lat 18°27'46", long 66°17'08". Owner: Dorado Beach Hotel. Name: Dorado Beach No. 7, AQUIFER.--Aymamon Limestone. WELL CHARACTERISTICS.--Drilled water-tabble well, diameter 18 in (0.46 m). Depth 100 ft (30.5 m). DATUM.--Elevation of land-surface datum is about 39.0 ft (11.9 m) above mean sea level, from topographic map. Measuring point: Hole on side of casing. 1.10 ft (0.34 m) above land-surface datum. REMARKS.--Abandoned Observation well. Automatic recorder installed on November 7,1985. Water levels affected by nearby pumping well. PERIOD OF RECORD.-- November 1985 to September 1987. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 18.23 ft (5.56 m) below land-surface datum, Nov. 16, 1985; lowest water level recorded. 20.31 ft (6.19 0 below land-surface datum, Mar. 8, 1987. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 19.86 19.63 19.41 19.80 20.01 19.95 19.84 19.33 19.11 19.07 19.31 19.56 2 19.77 19.62 19.45 19.84 20.00 19.95 19.89 19.33 19.13 19.07 19.37 19.55 3 19.69 19.60 19.54 19.85 20.02 19.94 19.93 19.36 19.11 19.08 19.38 19.58 4 19.70 19.54 19.61 19.89 19.99 19.98 19.98 19.32 19.10 19.13 19.39 19.53 5 19.71 19.57 19.66 19.84 19.98 19.99 20.00 19.32 19.15 19.19 19.42 19.48 6 19.76 19.57 19.71 19.74 19.95 20.06 20.01 19.34 19.23 19.21 19.48 19.43 7 19.81 19.62 19.74 19.74 19.97 20.12 20.03 19.35 19.19 19.22 19.44 19.38 8 19.81 19.56 19.76 19.80 19.95 20.16 20.03 19.36 19.20 19.25 19.38 19.30 9 19.86 19.54 19.72 19.94 19.94 20.14 20.04 19.37 19.26 19.24 19.33 19.30 10 19.87 19.55 19.71 20.00 19.95 20.05 20.00 19.42 19.26 19.20 19.31 19.31 11 19.89 19.48 19.70 20.01 19.95 20.01 19.99 19.53 19.25 19.16 19.28 19.34 12 19.95 19.47 19.71 20.07 19.84 20.06 19.62 19.55 19.24 19.13 19.28 19.39 13 19.88 19.31 19.72 20.03 19.81 20.11 19.26 19.61 19.24 19.08 19.32 19.43 14 19.82 19.27 19.66 20.00 19.78 20.04 19.21 19.64 19.22 19.10 19.39 19.47 15 19.73 19.26 19.71 20.00 19.76 20.00 18.94 19.62 19.22 19.12 19.42 19.50 16 19.64 19.26 19.69 20.00 19.77 19.97 18.82 19.63 19.23 19.16 19.48 19.52 17 19.59 19.26 19.69 20.00 19.79 19.89 18.76 19.60 19.22 19.23 19.57 19.46 18 19.61 19.25 19.72 19.98 19.77 19.80 18.75 19.56 19.23 19.26 19.58 19.44 19 19.62 19.29 19.80 20.00 19.86 19.82 18.81 19.52 19.22 19.29 19.57 19.43 20 19.65 19.35 19.79 19.98 19.91 19.84 18.84 19.44 19.23 19.32 19.55 19.43 21 19.66 19.41 19.78 19.91 19.92 19.86 18.86 19.38 19.24 19.35 19.57 19.40 22 19.65 19.46 19.75 19.93 19.93 19.87 18.92 19.21 19.12 19.36 19.52 19.38 23 19.68 19.51 19.77 19.90 19.96 19.83 18.93 19.13 19.08 19.34 19.50 19.38 24 19.70 19.55 19.83 19.94 20.05 19.83 18.99 19.17 19.12 19.34 19.48 19.35 25 19.77 19.57 19.79 19.92 20.02 19.86 19.04 19.23 19.15 19.32 19.49 19.39 26 19.81 19.54 19.76 19.94 19.98 19.90 19.09 19.02 19.15 19.30 19.39 19.44 27 19.81 19.51 19.68 19.94 19.94 19.94 19.14 19.06 19.19 19.29 19.39 19.53 28 19.79 19.46 19.)2 19.94 19.96 19.94 19.21 19.04 19.17 19.25 19.42 19.57 29 19.78 19.40 19.71 19.94 --- 19.98 19.30 19.02 19.14 19.26 19.46 19.64 30 19.70 19.41 19.71 19.97 20.00 19.29 19.05 19.11 19.26 19.50 19.61 31 19.65 --- 19.78 20.01 19.87 --- 19.12 --- 19.27 19.57 --- LOW 19.95 19.63 19.83 20.07 20.05 20.16 20.04 19.64 19.26 19.36 19.58 19.64 HIGH 19.59 19.25 19.41 19.74 19.76 19.80 18.75 19.02 19.08 19.07 19.28 19.30 WTR YR 1987 MEAN 19.6 LOW 20.16 HIGH 18.75 l\r"/AApi ND J F M AMJ J A SONDJ FM AMJ J AS 1985 1986 1987 GROUND-WATER LEVELS RIO DE LA PLATA BASIN 182548066171200. Local number, 215. LOCATION.--Lat 18°2548", long 66°1712". Owner: P.R. Aqueduct and Sewer Authority. Name: Maguayo No. 5. AQUIFER.--Aguada Limestone-Cibao Formation. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 20 in (0.51 m) 0-95 ft (0-29.0 m), cased 20 in (0.51 m) 0-60 ft (0-18.3 m), diameter 16 in (0.41 m) 95-145 ft (29.0-44.2 m), cased 16 in (0.41 m) 0-145 ft (0-44.2 m), perforated 65-145 ft (19.8-44.2 m). Depth 145 ft (44.2 m). DATUM.--Elevation of land-surface datum is about 66 ft (20.1 m) above mean sea level, from topographic map. Measuring point: Hole on side of casing, 1.60 ft (0.49 m) above land-surface datum. REMARKS.--Abandoned observation well. Automatic recorder installed on August 13, 1985. PERIOD OF RECORD.--October 1985 to May 10, 1987, discontinued. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 40.16 ft (12.24 m) below land-surface datum. Apr. 18, 1987; lowest water level recorded, 44.33 ft (13.51 m) below land-surface datum, Feb. 10, 1987. DAY OCT WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 43.96 43.98 43.27 43.76 44.21 43.93 43.79 41.64 2 43.97 43.99 43.28 43.77 44.22 43.95 43.82 41.71 3 43.99 43.99 43.31 43.78 44.23 43.97 43.85 41.76 4 44.00 43.99 43.34 43.80 44.24 43.98 43.87 41.82 5 44.01 43.98 43.36 43.81 44.26 43.99 43.90 41.89 6 44.03 43.92 43.39 43.82 44.28 44.01 43.94 41.93 7 44.04 43.82 43.41 43.84 44.29 44.03 43.96 41.98 8 44.05 43.71 43.43 43.86 44.30 44.05 43.97 42.03 9 44.06 43.60 43.46 43.87 44.31 44.06 43.98 42.06 10 44.07 43.52 43.48 43.90 44.32 44.08 44.00 42.09 11 44.08 43.45 43.50 43.92 44.28 44.09 44.03 12 44.09 43.40 43.52 43.95 44.16 44.12 43.78 13 44.10 43.30 43.54 43.97 44.10 44.13 42.94 14 44.11 43.27 43.56 43.99 44.03 44.15 42.17 15 44.10 43.22 43.57 44.00 43.96 44.14 41.24 16 44.08 43.19 43.59 44.01 43.93 44.12 40.62 17 44.08 43.18 43.61 44.02 43.91 43.97 40.26 18 44.08 43.15 43.62 44.04 43.90 43.86 40.16 19 44.07 43.14 43.64 44.05 43.90 43.76 40.27 20 44.07 43.14 43.66 44.06 43.90 43.70 40.42 21 44.07 43.15 43.67 44.07 43.90 43.68 40.58 22 44.02 43.16 43.69 44.08 43.89 43.67 40.72 23 44.01 43.18 43.70 44.09 43.90 43.66 40.85 24 44.00 43.20 43.72 44.11 43.91 43.67 40.97 25 43.99 43.23 43.73 44.13 43.92 43.67 41.07 26 43.99 43.24 43.72 44.14 43.94 43.68 41.19 27 44.00 43.25 43.71 44.17 43.94 43.69 41.29 28 43.99 43.25 43.71 44.19 43.95 43.70 41.39 29 43.99 43.26 43.72 44.19 43.71 41.48 30 44.00 43.26 43.73 44.20 43.73 41.57 31 43.99 43.75 44.20 43.77 LOW 44.11 43.99 43.75 44.20 44.32 44.15 44.03 HIGH 43.96 43.14 43.27 43.76 43.89 43.66 40.16 311 9. 40 iktc 42 zit( 410 44 > 1 erz 46 \„. ONDJFMAMJJ ASONDJ FM AMJJ AS 1985 1986 1987 312 GROUND-WATER LEVELS RIO DE LA PLATA BASIN 182530066135400. Local number, 216. LOCATION.--Lat 18°25'30", long 66°1354". Owner: P.R. Aqueduct and Sewer Authority. Name: 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 is about 13.0 ft (3.96 m) above mean sea level, from topographic map. Measuring point: Hole on side of casing, 1.80 ft (0.55 m) above land-surface datum. REMARKS.--Abandoned observation well. Automatic recorder installed on August 13, 1985. PERIOD OF RECORD.--October 1985 to September 1987. 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 13.98 13.72 12.84 12.95 13.70 13.84 13.97 12.25 10.43 9.74 11.13 11.41 2 13.93 13.72 12.88 12.95 13.69 13.84 14.01 12.26 10.47 9.74 11.18 11.37 3 13.98 13.71 12.77 12.97 13.72 13.85 14.03 12.28 10.23 9.75 11.22 11.35 4 14.01 13.67 12.93 13.14 13.74 13.86 14.07 12.25 10.38 9.74 11.26 11.36 5 14.03 13.65 12.98 13.16 13.75 13.89 14.11 12.28 10.48 10.23 11.30 11.35 6 14.05 13.57 13.02 13.16 13.77 13.94 14.12 12.31 10.51 10.37 11.44 11.38 7 14.08 13.50 13.02 12.86 13.81 13.99 14.12 12.34 9.78 10.44 11.44 11.40 8 14.08 13.30 13.02 13.21 13.84 14.01 14.10 12.34 9.72 10.48 11.45 11.42 9 14.09 13.19 13.04 13.27 13.85 14.03 13.93 12.38 9.72 10.48 11.46 11.45 10 14.09 13.10 13.05 13.32 13.89 14.04 14.13 12.41 10.38 10.50 11.07 11.21 11 14.10 13.05 13.08 13.32 13.80 14.06 14.11 12.42 10.47 10.53 11.05 11.17 12 14.12 13.03 13.10 13.36 13.63 14.08 13.49 12.43 10.56 10.57 11.06 11.11 13 14.12 12.85 13.10 13.37 13.53 14.10 12.75 12.45 10.61 10.60 11.10 11.08 14 14.12 12.85 13.23 13.36 13.47 14.12 12.52 12.51 10.66 10.65 11.16 11.13 15 13.34 12.85 13.11 13.35 13.43 14.07 12.05 12.56 10.36 10.68 11.20 11.14 16 13.16 12.80 13.09 13.35 13.43 14.04 11.91 12.59 10.16 10.71 11.23 11.16 17 13.77 12.77 13.10 13.36 13.42 13.88 11.70 12.63 10.10 10.75 11.28 11.20 18 13.77 12.74 13.12 13.36 13.46 13.73 11.67 12.61 10.09 10.78 11.32 11.21 19 13.20 12.74 13.16 13.43 13.51 13.71 11.65 12.54 10.46 10.82 11.34 11.24 20 13.08 12.76 13.17 13.46 13.39 13.69 11.68 12.30 10.50 10.87 11.31 11.28 21 12.96 12.81 13.16 13.43 13.55 13.71 11.72 12.05 10.48 10.92 11.34 11.31 22 12.83 12.86 13.16 13.44 13.59 13.73 11.78 11.67 9.56 10.96 11.36 11.35 23 13.32 12.89 13.18 13.46 13.64 13.75 11.83 11.51 9.40 11.00 11.41 11.40 24 13.48 12.85 13.21 13.49 13.70 13.76 11.91 11.47 9.62 11.07 11.45 11.44 25 13.66 12.90 13.13 13.56 13.84 13.76 11.99 11.48 9.68 11.10 11.48 11.93 26 13.72 12.86 13.07 13.64 13.87 13.77 12.03 10.90 9.75 11.18 11.44 12.05 27 13.67 12.85 13.05 13.69 13.79 13.79 12.07 10.71 9.82 11.21 11.44 12.11 28 13.68 12.84 13.07 13.70 13.82 13.82 12.12 10.51 9.88 11.12 11.45 12.15 29 13.66 12.82 13.11 13.70 --- 13.85 12.15 10.43 9.87 11.14 11.49 12.19 30 13.68 12.84 12.98 13.70 13.89 12.20 10.42 9.76 10.75 11.52 12.24 31 13.71 --- 12.96 13.70 13.94 --- 10.45 --- 11.05 11.56 --- LOW 14.12 13.72 13.23 13.70 13.89 14.12 14.13 12.63 10.66 11.21 11.56 12.24 HIGH 12.83 12.74 12.77 12.86 13.39 13.69 11.65 10.42 9.40 9.74 11.05 11.08 WTR YR 1987 MEAN 12.4 LOW 14.13 HIGH 9.40 ONDJFMAMJJASONDJFMAMJJ AS 1985 1986 1987 313 GROUND-WATER LEVELS RIO DE LA PLATA BASIN 182655066142400. Local number, 217. LOCATION.--Lat 18°26'55", long 66°14'24". Owner: U.S. Geological Survey. Name: Monserrate TW-2. AQUIFER.-Alluvial Deposits. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 4 in (0.10 m). cased 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 point: Top of shelter floor, 3.50 ft (1.07 m) above land-surface datum. REMARKS.--Observation well. Automatic recorder installed on August 20, 1985. PERIOD OF RECORD.--November 1985 to September 1987. 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, 1.92 ft (0.58 m) below land-surface datum, Apr 12, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 1.65 1.45 1.11 1.43 1.61 1.58 1.56 1.00 .32 .23 .75 1.08 2 1.62 1.45 1.16 1.45 1.60 1.57 1.58 1.02 .31 .23 .78 1.05 3 1.61 1.45 1.25 1.45 1.61 1.57 1.63 1.02 .35 .25 .78 1.07 4 1.60 1.42 1.32 1.49 1.62 1.59 1.67 .99 .28 .26 .81 1.03 5 1.63 1.39 1.36 1.44 1.61 1.61 1.71 1.01 .29 .32 .80 .98 6 1.67 1.33 1.37 1.40 1.61 1.65 1.73 1.03 .34 .41 .86 .98 7 1.71 1.26 1.36 1.37 1.62 1.72 1.77 1.04 .38 .49 .87 .97 8 1.70 1.16 1.36 1.41 1.65 1.78 1.74 1.01 .30 .48 .84 .96 9 1.71 1.07 1.34 1.52 1.67 1.78 1.76 1.03 .31 .51 .82 .99 10 1.68 1.05 1.36 1.59 1.70 1.74 1.74 1.07 .35 .49 .84 .91 11 1,65 1.02 1.38 1.63 1.66 1.73 1.73 1.11 .41 .48 .84 .85 12 1.69 1.03 1.40 1.65 1.53 1.74 1.09 1.13 .44 .48 .84 .79 13 1.63 .86 1.40 1.65 1.46 1.77 .55 1.15 .45 .48 .85 .81 14 1.61 .85 1.40 1.61 1.41 1.75 .66 1.18 .47 .50 .92 .82 15 1.51 .88 1.40 1.58 1.38 1.66 .38 1.19 .50 .54 .94 .84 16 1.44 .90 1.38 1.54 1.39 1.63 .32 1.22 .50 .54 .97 .88 17 1.44 .92 1.38 1.54 1.39 1.48 .28 1.25 .44 .56 1.03 .86 18 1.47 .90 1.40 1.54 1.44 1.36 .30 1.18 .41 .57 1.05 .81 19 1.46 .90 1.44 1.55 1.46 1.33 .37 1.15 .40 .62 1.05 .83 20 1.42 .97 1.45 1.54 1.51 1.35 .43 1.05 .35 .66 1.03 .86 21 1.39 1.04 1.44 1.52 1.52 1.38 .48 .87 .34 .68 1.04 .87 22 1.34 1.10 1.42 1.52 1.54 1.41 .53 .49 .33 .71 1.02 .88 23 1.37 1.13 1.42 1.51 1.59 1.42 .56 .46 .18 .70 1.02 .92 24 1.42 1.15 1.44 1.55 1.61 1.45 .62 .43 .18 .74 1.04 .93 25 1.44 1.15 1.39 1.57 1.64 1.47 .70 .50 .21 .73 1.04 1.01 26 1.49 1.11 1.32 1.61 1.64 1.51 .75 .27 .28 .72 1.02 1.05 27 1.51 1.07 1.27 1.63 1.59 1.54 .82 .19 .33 .72 1.03 1.12 28 1.49 1.05 1.32 1.64 1.59 1.53 .88 .18 .33 .69 1.03 1.15 29 1.48 1.05 1.35 1.63 --- 1.56 .94 .20 .33 .72 1.06 1.18 30 1.46 1.09 1.37 1.63 1.56 .97 .25 .27 .74 1.09 1.16 31 1.45 --- 1.42 1.62 1.56 --- .28 --- .73 1.14 --- LOW 1.71 1.45 1.45 1.65 1.70 1.78 1.77 1.25 .50 .74 1.14 1.18 HIGH 1.34 .85 1.11 1.37 1.38 1.33 .28 .18 .18 .23 .75 .79 WTR YR 1987 MEAN 1.11 LOW 1.78 HIGH .18 NDJFMAMJJ ASONDJ FM AMJJ AS 1985 1986 1987 314 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NUEVO BASINS 182623066111000. Local number, 218. LOCATION.--Lat 18°26'23", long 66°1110. Owner: P.R. Aqueduct and Sewer Authority. Name: Levittown No. 7. AQUIFER.--Alluvial deposits-Aymamon Limestone. WELL 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 point: Hole on pump base, 1.55 ft (0.47 m) above land-surface datum. REMARKS.--Abandoned observation well. Automatic recorder installed August 13, 1985. Water levels affected by nearby pumping well. PERIOD OF RECOR0.--October 1985 to September 1987. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 6.13 ft (1.87m) below land-surface datum,Feb. 22, 1987; 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 8.11 7.94 7.85 7.86 .09 8.14 8.27 7.79 6.28 6.49 7.12 7.87 2 8.07 7.93 7.93 7.88 .08 8.15 8.29 7.82 6.34 6.49 7.17 7.76 3 8.05 7.92 8.00 7.89 .10 8.16 8.30 7.73 6.38 6.50 7.17 7.75 4 8.05 7.92 8.05 7.91 .10 8.17 8.43 7.69 6.40 6.51 7.41 7.68 5 8.06 7.92 8.10 7.88 .10 8.19 8.50 7.68 6.45 6.71 7.53 7.65 6 8.09 7.91 8.17 7.83 .09 8.26 8.49 7.68 6.50 7.08 7.62 7.61 7 8.12 7.86 8.20 7.82 .26 8.43 8.41 7.70 6.48 7.59 7.39 7.60 8 8.12 7.77 8.21 7.86 .42 8.59 8.39 7.67 6.47 7.04 7.35 7.59 9 8.15 7.71 8.23 7.93 .33 8.50 8.43 7.69 6.51 7.02 7.44 7.58 10 8.16 7.67 8.25 7.97 .27 8.36 8.40 7.71 6.51 7.00 7.46 7.47 11 8.15 7.61 7.97 7.99 .24 8.33 8.44 7.72 6.55 7.00 7.52 7.32 12 8.18 7.61 7.92 8.00 .21 8.35 8.28 7.73 6.70 7.00 7.37 7.31 13 8.15 7.56 8.03 8.00 .09 8.34 7.70 7.79 6.76 7.01 7.37 7.27 14 8.13 7.51 8.82 7.99 .04 8.46 7.60 7.81 6.79 7.02 7.47 7.25 15 8.11 7.49 8.08 8.00 .02 8.61 7.31 7.80 6.82 7.05 7.55 7.27 16 8.05 7.48 7.94 7.99 .01 8.53 7.18 7.81 6.82 6.88 7.62 7.27 17 8.03 7.42 7.90 8.00 .11 8.37 7.08 7.84 6.81 6.89 7.66 7.28 18 8.03 7.41 7.89 7.98 .03 8.28 7.06 7.81 6.82 6.88 7.69 7.29 19 8.03 7.32 7.89 8.00 .05 8.24 7.08 7.79 6.83 6.90 7.72 7.28 20 8.03 7.35 8.03 7.99 .07 8.23 7.09 7.71 6.86 6.91 7.62 7.29 21 8.01 7.39 8.15 7.97 .06 8.35 7.12 7.58 6.86 6.95 7.59 7.34 22 7.98 7.41 8.04 7.99 .64 8.39 7.15 7.27 6.69 6.99 7.61 7.34 23 7.96 7.45 7.97 7.97 .22 8.30 7.17 7.17 6.48 6.97 7.83 7.35 24 7.97 7.48 7.96 8.00 .16 8.19 7.28 7.10 6.45 6.98 7.87 7.35 25 7.99 7.50 7.88 8.16 .15 8.15 7.42 7.09 6.42 7.00 7.90 7.38 26 8.00 7.46 7.84 8.16 .16 8.16 7.50 6.52 6.41 7.01 7.86 7.41 27 8.01 7.44 7.95 8.09 .14 8.17 7.58 6.39 6.43 7.02 7.88 7.46 28 8.00 7.72 8.06 8.08 .14 8.29 7.67 6.23 6.68 7.03 7.85 7.52 29 8.00 7.75 7.87 8.09 --- 8.38 7.71 6.17 6.57 7.08 7.84 7.54 30 7.98 7.81 7.84 8.09 8.33 7.76 6.18 6.51 7.07 7.88 7.55 31 7.97 --- 7.87 8.09 8.30 --- 6.23 --- 7.09 7.89 --- LOW 8.18 7.94 8.82 8.16 8.64 8.61 8.50 7.84 6.86 7.59 7.90 7.87 HIGH 7.96 7.32 7.84 7.82 8.01 8.14 7.06 6.17 6.28 6.49 7.12 7.25 WTR YR 1987 MEAN 7.66 LOW 8.82 HIGH 6.17 V 14‘`firwi ONDJ F MAMJ A 0 J F MAMJJ AS 1985 1986 1987 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NUEVO BASINS 182441066082600. Local number, 219. LOCATION.--Lat 18°24'41, long 66°0826". Owner: Department of Defense. Name: Ft. Buchanan No. 1, Buchanan Park well. AQUIFER.--Cibao Formation. WELL CHARACTERISTICS.--Drilled water-table well, diameter 10 in (0.25 m), cased 10 in (0.25 m) 0-270 ft (0-82.3 m), perforated 46-685 ft (14.0-20.7 m), 88-120 ft (26.8-36.6 m), 160-191 ft (48.8-58.2 m), 240-270 ft (73.2-82.3 m). Depth 270 ft (82.3 m). DATUM.--Elevation of land-surface datum is about 66.0 ft (20.1 m) above mean sea level, from topographic map. Measuring point: Hole on side of casing, 0.75 ft (0.23 m) above land-surface datum. Prior June 30, 1986, top of shelter floor, 3.59 ft (1.09 m) above land-surface datum. REMARKS.--Abandoned observation well. Automatic recorder installed on December 20, 1985. Estimated noon value: June 30. PERIOD OF RECORD.--December 1985 to September 1987. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 38.10 ft (11.61 m) below land-surface datum, June 16, 1986; lowest water level recorded, 43.32 ft (13.20 m) below land-surface datum. Mar. 15, 1987. DAY OCT WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 41.85 41.30 40.61 41.64 42.16 42.66 42.77 41.91 40.05 39.22 39.99 41.42 2 41.92 41.22 40.63 41.70 42.12 42.69 42.83 41.95 40.03 39.24 40.01 41.44 3 42.01 41.16 40.69 41.79 42.08 42.73 42.90 41.97 40.04 39.25 39.99 41.34 4 42.08 41.15 40.73 41.83 42.08 42.78 42.92 41.99 39.95 39.23 39.95 41.16 5 42.15 41.16 40.75 41.80 42.07 42.84 42.92 42.07 39.85 39.20 39.99 41.03 6 42.20 41.22 40.78 41.79 42.05 42.92 42.91 42.15 39.72 39.15 39.97 40.96 7 42.31 41.17 40.81 41.89 42.05 42.99 42.96 42.25 39.60 39.11 40.92 8 42.38 41.06 40.86 42.04 42.04 43.03 42.99 42.30 39.58 39.11 40.90 9 42.38 40.86 40.89 42.11 42.07 43.05 43.01 42.36 39.62 39.11 40.92 10 42.30 40.73 40.93 42.17 42.13 43.09 43.06 42.42 39.58 39.13 40.04 40.93 11 42.26 40.65 40.98 42.20 42.18 43.19 43.06 42.46 39.63 39.16 40.06 40.76 12 42.25 40.64 41.06 42.26 42.16 43.30 42.77 42.55 39.66 39.17 40.09 40.61 13 42,21 40.58 41.07 42.27 42.11 43.31 42.38 42.64 39.67 39.17 40.13 40.47 14 42.19 40.53 41.08 42.33 42.04 43.29 42.08 42.69 39.68 39.19 40.19 40.37 15 42.18 40.52 41.08 42.25 41.95 43.31 41.77 42.71 39.68 39.23 40.21 40.28 16 42.17 40.47 41.09 42.26 41.92 43.29 41.56 42.78 39.62 39.24 40.23 40.39 17 42.15 40.41 41.11 42.26 41.87 43.14 41.37 42.87 39.52 39.26 40.26 40.53 18 42.15 40.44 41.14 42.27 41.93 43.00 41.24 42.84 39.51 39.41 40.31 40.63 19 42.14 40.43 41.18 42.24 42.00 42.85 41.19 42.81 39.52 39.60 40.40 40.79 20 42.07 40.46 41.23 42.19 42.07 42.72 41.16 42.65 39.58 39.84 40.51 40.95 21 42.03 40.49 41.27 42.15 42.11 42.67 41.16 42.16 39.60 39.90 40.61 41.12 22 41.93 40.49 41.31 42.14 42.19 42.62 41.18 41.89 39.43 39.89 40.70 41.27 23 41.87 40.52 41.38 42.18 42.26 42.59 41.25 41.68 39.21 39.92 40.76 41.42 24 41.71 40.55 41.43 42.23 42.32 42.62 41.34 41.56 39.15 39.99 40.86 41.55 25 41.54 40.55 41.45 42.25 42.40 42.66 41.42 41.47 39.14 39.99 40.95 41.69 26 41.48 40.58 41.42 42.25 42.49 42.68 41.50 41.12 39.18 39.94 41.05 41.76 27 41.44 40.59 41.42 42.27 42.54 42.71 41.56 40.77 39.23 39.94 41.10 41.78 28 41.32 40.63 41.47 42.30 42.62 42.72 41.65 40.46 39.23 39.94 41.16 41.78 29 41.26 40.62 41.51 42.32 42.72 41.76 40.28 39.25 39.97 41.23 41.78 30 41.27 40.62 41.53 42.29 42.72 41.83 40.16 39.27 40.01 41.30 41.78 31 41.34 41.57 42.23 42.74 40.11 40.01 41.37 LOW 42.38 41.30 41.57 42.33 42.62 43.31 43.06 42.87 40.05 40.01 41.78 HIGH 41.26 40.41 40.61 41.64 41.87 42.59 41.16 40.11 39.14 39.11 40.28 9 36 ICA0j 38 Li w w z < ceu- 40 w I 42 cr z w s-- < 44 DJ FMAMJJ ASONDJ FAIAMJ J A S 1985 1986 1987 315 316 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NUEVO BASINS 182413066044000. Local number, 220. LOCATION.--Lat 18°24'13", long 66'04'40". Owner: P.R. Aqueduct and Sewer Authority. Name: 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 point: Top of shelter floor, 3.00 ft (0.91 m) above land-surface datum. REMARKS.--Abandoned observation well. Automatic recorder installed on Feb. 6, 1986. Water levels affected by nearby pumping well. PERIOD OF RECORD.--February 1986 to September 1987. 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, 0.90 ft (0.21 m) below land-surface datum, Oct. 16, 1986. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .58 + .24 + .47 + .10 .03 .25 + .11 * .45 +1.10 + .98 * .36 .12 2 .59 + .25 + .43 + .06 .01 .26 + .07 + .44 +1.09 + .95 + .34 .13 3 .62 + .26 + .38 + .03 .02 .28 + .03 + .42 +1.09 + .91 + .36 .13 4 .53 + .26 * .33 + .04 .03 .25 .00 * .42 *1.09 + .89 + .34 .02 5 .51 + .26 + .30 + .07 .04 .28 .01 + .39 +1.08 + .88 + .34 .00 6 .46 + .27 + .27 + .06 .03 .31 .01 * .38 *1.08 + .87 + .34 .02 7 .47 + .34 + .25 + .05 .06 .35 .04 * .35 +1.08 + .85 + .32 .04 a .53 + .46 + .25 * .01 .09 .36 .03 * .33 +1.08 + .85 + .30 .04 9 .02 .11 .36 .06 + .32 +1.05 * .86 + .31 .09 10 . . : ::2232 .04 .14 .07 +1.04 + 36 .12 .V9 :5672 .31 + .30 * .85 11 .20 * .64 + .21 .05 .13 .32 .02 + .29 *1.01 * .83 + .35 .01 12 .19 * .65 * .18 .08 .06 .34 + .37 * .29 + .97 + .79 + .33 * .04 13 .19 + .69 * .19 .09 * .01 .35 * .65 * .27 + .95 * .76 + .31 + .12 14 .19 + .71 + .20 .08 + .04 .36 + .86 + .25 ,.92 + .71 + .27 + .16 15 .22 + .77 + .22 .03 + .03 .28 +1.06 + .24 + .94 ,.68 + .25 + .18 16 .80 * .80 + .24 .01 .00 .12 *1.07 + .21 + .89 + .66 + .23 .17 17 .70 * .88 + .22 .00 .01 * .24 +1.07 + .16 + .84 + .64 + .19 + .16 18 .52 + .87 + .19 .02 .05 + .39 +1.03 ,.18 + .80 + .62 + .15 + .15 19 .44 + .87 + .15 .01 .08 + .48 + .95 + .28 + .80 + .60 + .12 --- 20 .38 + .83 + .14 .03 .10 + .51 + .91 + .42 + .77 + .56 + .09 21 .33 * .78 * .11 .04 .11 * .51 * .85 * .80 * .79 * .54 + .05 --- 22 .18 + .75 + .08 .05 .16 + .49 + .80 + .87 *1.03 .- .53 + .03 .03 23 .13 + .69 * .05 .06 .19 * .47 * .75 + .97 +1.09 * .49 * .01 .08 24 + .03 + .64 * .02 .10 .21 + .43 * .70 + .98 *1.10 * .45 .01 .09 25 + .12 + .60 + .05 .13 .23 + .37 + .65 * .94 +1.10 + .42 .03 .13 26 + .12 + .57 * .13 .16 .24 + .32 * .61 +1.08 *1.09 + .42 .03 .17 27 + .17 + .55 + .18 .20 .22 * .28 + .59 +1.11 *1.08 * .40 .06 .21 28 * .26 * .53 * .20 .23 .23 + .24 + .56 +1.10 +1.06 + .41 .09 .22 29 + .28 + .52 * .19 .25 --- * .20 + .51 +1.10 +1.00 + .39 .10 .22 30 * .28 * .50 + .17 .19 + .17 + .48 +1.10 + .99 + .37 .11 .22 31 + .26 --- + .15 .11 + .14 --- +1.10 --- * .37 .12 --- LOW .80 + .88 * .02 .25 .24 .36 .07 + .16 + .77 , .37 .12 HIGH + .28 + .24 + .47 + .10 + .04 + .51 +1.07 +1.11 +1.10 + .98 .36 0 2 4 F M A MJJ ASONDJ FM AMJ A 1986 1987 * Above land-surface datum. 317 GROUND-WATER LEVELS RIO HONDO TO RIO PUERTO NUEVO BASINS 182436066031200. Local number, 221. LOCATION.--Lat 18°2436", long 66°03121 . Owner: P.R. Highway Authority Name: 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 m) 0-107 ft (0-32.36 m), perforated 19-107 ft (5.79-32.6 m). D'i)th 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 point: Hole on side of cas:ng, 0.70 ft (0.21 m) above land-surface datum. Prior July 28, 1986, top of shelter floor, 3.14 ft (0.96 m) abcve land-surface datum. REMARKS.--Observation well. Automatic recorder installed on Dec. 17, 1985. PERIOD OF RECORD.--December 1985 to September 1987. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 1.48 ft (0.45 m) below land-surface datum, Apr. 12, 1987; 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 10.29 5.13 6.23 7.61 8.07 10.00 7.68 7.44 5.07 6.79 8.27 10.52 2 10.50 5.10 6.40 7.73 8.14 10.14 7.80 7.51 5.41 6.93 8.34 10.61 3 10.56 5.19 6.44 7.66 8.33 10.19 7.90 7.53 5.62 7.05 8.29 10.73 4 9.92 5.42 6.59 7.75 8.49 10.29 8.00 7.53 4.70 7.05 7.92 10.73 5 10.11 5.46 6.73 7.79 8.65 10.35 8.07 7.64 5.10 6.34 8.04 10.81 6 10.26 5.33 6.86 7.94 8.61 10.53 8.12 7.67 5.52 6.58 8.19 10.92 7 10.46 3.89 6.96 7.97 8.72 10.66 8.19 7.80 5.75 6.56 8.30 11.03 8 7.98 3.18 7.08 8.10 8.76 10.80 8.25 7.88 5.90 6.48 8.39 11.17 9 8.03 3.36 7.10 8.19 8.80 10.95 8.35 7.90 5.99 6.64 8.44 11.28 10 7.80 3.80 7.1:2 8.25 9.05 9.92 8.45 7.99 6.26 6.49 8.55 11.41 11 7.93 4.27 7.09 8.29 9.07 10.08 7.29 8.07 6.69 8.60 11.51 12 8.04 4.47 7.19 8.43 7.72 10.21 1.98 8.06 6.86 8.65 10.11 13 8.06 4.11 7.26 8.54 8.07 10.35 2.68 8.12 7.03 8.47 9.51 14 8.06 4.64 7.03 8.44 8.19 10.49 3.17 8.26 7.18 8.57 9.48 15 7.96 4.29 6.99 8.20 8.27 8.69 3.42 8.32 7.27 8.69 9.53 16 7.37 4.12 7.08 8.13 8.41 7.08 4.17 8.45 7.38 8.78 9.64 17 7,22 3.88 7.24 8.28 8.54 3.01 4.33 8.56 7.44 8.88 9.77 18 7.44 4.44 7.39 8.46 8.70 3.97 4.87 8.45 7.51 8.99 9.89 19 7.59 4.93 7.46 8.56 8.81 4.87 5.31 8.13 7.57 9.11 10.07 20 7.65 5.30 7.57 8.66 8.96 5.45 5.59 4.04 7.67 9.19 10.24 21 7.41 5.59 7.64 8.75 9.10 5.83 5.80 2.92 7.72 9.32 10.41 22 5.28 5.75 7.73 8.85 9.23 6.08 6.02 3.15 7.80 9.44 10.54 23 5.88 5.89 7.81 8.97 9.35 6.34 6.24 3.88 7.86 9.56 10.64 24 3.46 6.04 7.88 9.07 9.46 6.58 6.44 4.47 7.94 9.70 10.80 25 4.22 6.16 7.08 9.14 9.61 6.72 6.61 5.00 8.01 9.83 10.94 26 4.82 5.67 6.85 9.23 9.77 6.89 6.76 2.87 7.83 9.94 11.12 27 4.17 5,78 6.90 9.31 9.74 7.08 6.91 2.70 8.05 10.06 11.28 28 3.88 5.59 7.04 9.44 9.86 7.27 7.06 3.20 7.91 10.18 11.40 29 4.48 5.78 7.22 9.58 --- 7.38 7.22 3.72 --- 8.07 10.26 11.48 30 4.95 6.01 7.37 9.22 7.50 7.34 4.34 6.65 8.15 10.32 11.40 31 5.30 --- 7.47 9.25 7.59 --- 4.84 --- 8.21 10.43 --- LOW 10.56 6.16 7.88 9.58 9.86 10.95 8.45 8.56 8.21 10.43 11.51 HIGH 3.46 3.18 6.23 7.61 7.72 3.01 1.98 2.70 6.34 7.92 9.48 tt- DJ FM AMJJ ASONDJ FM AMJJ AS 1985 1986 1987 318 GROUND-WATER LEVELS RIO GRANDE DE LOIZA BASIN 182515065594100. Local number, 222. LOCATION.--Lat 18°25'15", long 65°5941", Owner: U.S. Geological Survey. Name: 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 point: 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.--Observation well. Automatic recorder installed on February 5, 1986. PERIOD OF RECORD.--February 1986 to Sept?mber 1987. 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 1986 TO SEPTEMBER 1987 ICTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 5.90 5.38 5.36 5.63 5.85 5.73 5.85 6.03 5.95 5.80 5.67 5.75 2 5.70 5.30 5.43 5.75 5.87 5.75 5.90 5.97 5.95 5.78 5.75 5.75 3 5.52 5.39 5.56 5.76 5.96 5.80 6.03 6.00 5.95 5.81 5.87 5.75 4 5.46 5.41 5.72 5.93 5.89 5.87 6.12 5.85 5.89 5.84 5.75 5.74 5 5.49 5.54 5.90 5.83 5.88 5.89 6.11 5.85 5.96 5.96 5.75 5.75 6 5.60 5.71 5.84 5.73 5.84 6.07 6.03 5.84 6.02 5.98 5.75 5.69 7 5.68 5.85 5.92 5.67 5.82 5.95 6.07 5.85 5.99 5.82 5.75 5.66 8 5.77 5.83 5.92 5.75 5.82 6.03 6.09 5.98 6.01 5.76 5.74 5.60 9 5,.89 5.86 5.87 6.02 5.77 5.87 6.12 5.88 6.12 5.78 5.70 5.62 10 6.01 5.85 5.82 6.04 5.72 5.78 5.97 6.00 6.10 5.61 5.74 5.70 11 5.99 5.70 5.78 6.01 5.75 5.76 5.81 6.06 5.99 5.68 5.73 5.75 12 6.06 5.63 5.76 6.01 5.72 5.78 5.58 6.08 5.91 5.61 5.73 5.74 13 5.87 5.52 5.66 5.92 5.71 5.82 5.77 6.17 5.89 5.67 5.82 5.74 14 5.75 5.33 5.51 5.86 5.69 5.66 5.77 6.28 5.85 5.71 5.75 5.75 15 5.61 5.40 5.60 5.88 5.73 5.64 5.69 6.22 5.83 5.72 5.70 5.69 16 5.45 5.38 5.55 5.90 5.78 5.65 5.72 6.11 5.87 5.69 5.75 5.69 17 5.37 5.34 5.60 5.91 5.82 5.57 5.64 6.06 5.87 5.63 5.75 5.69 18 5.31 5.24 5.65 5.88 5.83 5.64 5.73 6.08 5.90 5.62 5.75 5.70 19 5.38 5.39 5.76 5.96 5.90 5.70 5.79 6.03 5.98 5.62 5.75 5.68 20 5.46 5.52 5.72 5.92 6.05 5.79 5.80 5.82 5.99 5.72 5.75 5.68 21 5.46 5.62 5.72 5.86 5.96 5.79 5.81 5.80 6.08 5.86 5.76 5.69 22 5.54 5.64 5.69 5.88 5.91 5.75 5.78 5.86 5.88 5.76 5.85 5.69 23 5.65 5.70 5.76 5.84 5.97 5.72 5.76 5.82 5.86 5.76 5.83 5.69 24 5.74 5.76 5.83 5.86 5.90 5.67 5.80 5.86 5.87 5.75 5.75 5.63 25 5.82 5.79 5.76 5.78 5.88 5.69 5.78 5.90 5.85 5.71 5.75 5.67 26 5.83 5.72 5.76 5.82 5.73 5.75 5.81 5.90 5.84 5.66 5.75 5.69 27 5.82 5.63 5.78 5.71 5.69 5.79 5.82 5.90 5.85 5.69 5.75 5.75 28 5.79 5.52 5.63 5.69 5.70 5.72 5.88 5.88 5.79 5.65 5.76 5.75 29 5.72 5.41 5.57 5.67 5.86 5.89 5.88 5.75 5.73 5.86 5.67 30 5.59 5.36 5.60 5.70 5.83 5.96 5.87 5.82 5.72 5.75 5.67 31 5.45 5.65 5.78 5.91 5.88 5.82 5.76 LOW 6.06 5.86 5.92 6.04 6.05 6.07 6.12 6.28 6.12 5.98 5.87 5.75 HIGH 5.31 5.24 5.36 5.63 5.69 5.57 5.58 5.80 5.75 5.61 5.67 5.60 WTR YR 1987 MEAN 5.78 LOW 6.28 HIGH 5.24 1. 1/4.1 0, 1 Jy r NrL FM AMJJ ASONDJ FM AMJ J AS 1986 1987 319 GROUND-WATER LEVELS RIO HUMACAO TO RIO SECO BASINS 175858066100200. Local number, 6. LOCATION.--Lat 17°58'58", long 66°1002". Owner: Doctor Bruno. Name: Juana 5. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 16 in (0.41 m). Depth 173 ft (52.74 m) reported, 110 ft (33.54 0 measured. DATUM.--Elevation of land-surface datum is about 127 ft (38.7 m) above mean sea level, from topographic map. Measuring point: Top of shelter floor, 3.00 ft (0.91 m) above land-surface datum. After Aug. 7, 1981, top of 16 in (0.41 m) casing, 1.55 ft (0.47 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.--November 1960 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 26.20 ft (7.99 m) below land-surface datum, Dec. 10, 1979; lowest water level recorded, 65.95 ft (20.10 m) below land-surface datum, June 2, 1968. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 49.83 51.27 50.34 45.91 47.33 48.11 49.94 51.56 51.81 49.43 51.18 50.67 2 49.92 51.32 50.19 45.96 47.23 47.89 50.00 51.45 51.80 49.28 51.23 50.54 3 49.96 51.37 50.07 45.98 47.04 47.92 50.07 51.30 51.75 49.11 51.30 50.43 4 49.80 51.44 49.80 46.04 47.02 48.16 50.18 51.11 51.62 48.91 51.37 50.25 5 49.61 51.50 49.41 46.13 47.13 48.38 50.26 50.93 51.39 48.77 51.39 50.19 6 49.43 51.57 49.18 46.26 47.26 48.45 50.33 50.75 51.16 48.65 51.37 50.13 7 49.31 51.63 49.10 46.38 47.38 48.47 50.26 50.45 50.97 48.64 51.33 50.09 8 49.34 51.68 49.03 46.48 47.44 48.29 50.13 50.38 50.83 48.71 51.25 50.10 9 49.56 51.75 48.90 46.56 47.31 48.08 49.97 50.56 50.73 48.88 51.23 50.12 10 49.64 51.80 48.73 46.65 47.12 47.98 49.78 50.65 50.66 49.04 51.24 50.16 11 49.56 51.86 48.53 46.77 47.14 48.05 49.85 50.57 50.62 49.20 51.26 50.20 12 49.68 51.90 48.29 46.86 47.21 48.37 50.04 50.46 50.60 49.35 51.29 50.24 13 49.81 51.95 48.05 46.92 47.26 48.67 50.21 50.28 50.59 49.58 51.31 50.25 14 49.94 51.88 47.81 46.96 47.30 48.89 50.36 50.02 50.58 49.85 51.19 50.21 15 50.07 51.76 47.57 46.97 47.33 49.07 50.49 49.52 50.55 50.06 51.11 50.05 16 50.19 51.65 47.35 46.99 47.33 49.19 50.61 49.51 50.49 50.20 51.16 49.76 17 50.30 51.53 47.13 46.99 47.33 49.25 50.75 49.58 50.53 50.25 51.24 49.75 18 50.38 51.41 46.94 47.00 47.37 49.28 50.87 49.58 50.60 50.24 51.26 49.86 19 50.45 51.29 46.76 47.04 47.46 49.35 50.98 49.58 50.67 50.21 51.19 49.92 20 50.53 51.16 46.62 47.13 47.55 49.43 51.09 49.74 50.69 50.07 51.21 49.85 21 50.64 51.04 46.53 47.26 47.67 49.50 51.17 50.00 50.49 49.72 51.24 49.55 22 50.75 50.95 46.48 47.41 47.78 49.47 51.27 50.32 49.97 49.30 51.26 49.24 23 50.84 50.88 46.45 47.53 47.91 49.16 51.30 50.61 49.55 49.14 51.28 49.04 24 50.92 50.83 46.42 47.63 48.06 48.78 51.33 50.87 49.20 49.45 51.31 49.08 25 50.99 50.79 46.36 47.69 48.18 48.60 51.30 51.12 48.94 49.78 51.30 49.11 26 51.04 50.75 46.31 47.47 48.31 48.69 51.40 51.31 48.94 50.06 51.23 49.28 27 51.08 50.72 46.18 47.20 48.38 49.01 51.46 51.47 49.17 50.30 51.11 49.46 28 51.11 50.68 46.02 47.14 48.35 49.32 51.49 51.59 49.40 50.54 50.96 49.62 29 51.14 50.59 45.87 47.20 49.51 51.51 51.67 49.50 50.76 50.79 49.77 30 51.18 50.48 45.78 47.24 49.69 51.54 51.76 49.53 50.96 50.77 49.91 31 51.23 45.84 47.27 49.82 51.80 51.10 50.72 LOW 51.23 51.95 50.34 47.69 48.38 49.82 51.54 51.80 51.81 51.10 51.39 50.67 HIGH 49.31 50.48 45.78 45.91 47.02 47.89 49.78 49.51 48.94 48.64 50.72 49.04 WTR YR 1987 MEAN 49.6 LOW 51.95 HIGH 45.78 3x 22 LAQ Lwci 32 zit( A 42 J w v.) > 52 ccz W5 4t 62 3 ONDJ FMAMJJ ASONDJ FMAMJ J ASONDJFMAMJ AS 1984 1985 1986 1987 320 GROUND-WATER LEVELS RIO GUAYANES 8ASIN 180415065513900. Local number, 96. LOCATION.--Lat 18°0415, long 65°5139. 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.--Observation recording well. PERIOD OF RECORD.--April 25, 1978 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 13.39 ft (4.08 m) below land-surface datum, Nov. 18, 1985; 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 17.90 18.14 16.00 16.11 17.59 19.05 17.55 17.14 16.08 14.44 16.06 17.46 2 18.03 18.17 16.00 16.14 17.56 19.09 17.58 17.18 16.45 14.43 16.02 17.42 3 18.08 19.00 16.00 16.17 17.55 19.08 17.02 17.04 16.45 14.44 16.19 17.42 4 18.20 19.02 16.00 16.18 17.70 19.09 17.05 17.08 16.15 14.44 16.17 17.45 5 18.24 19.05 16.19 16.19 17.70 19.11 17.08 17.12 16.07 14.45 16.16 17.49 6 18.23 19.08 16.00 16.19 17.51 19.12 17.13 17.13 16.02 14.45 16.14 17.52 7 18.21 19.12 16.01 16.18 17.73 19.08 18.01 17.15 16.18 14.44 16.15 17.57 8 18.09 19.14 16.03 16.15 17.00 19.01 18.08 17.16 16.17 14.43 16.02 17.01 9 18.40 19.13 16.06 16.14 17.04 19.17 18.18 17.17 16.14 14.44 16.12 17.07 10 18.48 19.10 16.16 16.14 17.08 19.10 18.07 17.17 16.12 14.47 16.42 17.12 11 18.50 19.05 16.45 16.14 17.14 19.08 18.15 17.16 16.05 14.53 16.57 17.18 12 18.49 18.17 16.53 16.12 18.06 19.09 18.42 17.14 16.01 14.42 16.52 18.06 13 18.58 18.00 16.43 16.11 18,13 19.03 18.40 17.19 16.01 14.72 16.06 18.10 14 18.05 18.41 16.45 16.11 18.03 18.11 18.14 17.56 16.03 14.03 16.17 18.14 15 18.10 18.44 16.43 16.10 18.12 18.00 18.03 17.49 16.06 14.12 17.07 18.09 16 18.16 18.04 16.58 16.09 18.41 18.46 18.11 17.08 16.07 15.07 17.09 17.18 17 19.01 18.03 16.51 16.08 18.47 18.51 17.19 18.13 16.09 15.07 17.12 17.06 18 19.03 17.02 16.47 16.08 18.56 18.17 17.02 18.12 16.12 15.50 17.17 17.75 19 19.03 17.44 16.46 16.10 18.57 18.03 17.43 18.47 16.14 15.51 17.04 17.62 20 18.19 17.47 16.47 16.13 18.43 18.12 17.44 18.57 16.09 15.12 17.10 17.52 21 18.17 17.12 16.53 16.17 18.54 18.00 17.09 18.42 15.19 16.09 17.16 17.44 22 18.16 17.02 16.42 17.03 18.02 17.10 17.02 18.41 15.59 16.03 17.42 17.16 23 18.15 17.14 16.50 17.12 18.10 17.01 17.17 18.51 15.56 16.12 17.45 17.10 24 18.14 17.05 16.58 17.03 18.18 17.55 17.16 18.40 15.17 16.17 17.47 17.06 25 18.11 16.15 16.02 17.16 19.05 17.51 17.14 18.04 15.00 16.19 17.50 17.03 26 18.11 16.07 16.05 17.48 19.12 17.49 17.14 18.07 15.02 16.40 17.54 17.02 27 18.10 16.01 16.07 17.56 19.17 17.48 17.14 17.06 14.06 16.41 17.57 17.02 28 18.10 16.00 16.07 17.45 19.01 17.48 17.14 17.48 14.49 16.41 17.40 17.03 29 18.11 16.00 16.07 17.51 --- 17.48 17.14 17.49 14.56 16.41 17.43 17.04 30 18.11 16.00 16.07 17.00 17.50 17.14 17.09 14.48 16.18 17.47 17.05 31 18.11 --- 16.09 17.01 17.52 --- 17.10 --- 16.13 17.49 --- LOW 19.03 19.14 16.58 17.56 19.17 19.17 18.42 18.57 16.45 16.41 17.57 18.14 HIGH 17.90 16.00 16.00 16.08 17.00 17.01 17.02 17.04 14.06 14.03 16.02 17.01 WTR YR 1987 MEAN 17.1 LOW 19.17 HIGH 14.03 9x 10 `Alp L'a 14 L,J„J , u.0 ri . 18 z ef r\kviry A Lu >v) 22 etz W < 26 3 ONDJFMAMJJASONDJFMAMJJASONDJFMAMJJAS 1984 1985 1986 1987 321 GROUND-WATER LEVELS RIO SALINAS TO RIO JACAGUAS BASINS 175829066232200. Local number, 87. LOCATION.--Lat 17°5829", long 662322". Owner: Francisco Alomar. Name: Alomar 1. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 20 in (0.51 m), iron cased Depth 112 ft (34.14 m). DATUM.--Elevation of land-surface datum is 35.32 ft (10.77 m) above mean sea level. Measuring point: Bottom of clean-out shelter door, 2.50 ft (0.76 m) above land-surface datum. Prior to August 1981, top of recorder shelter floor, 4,00 ft (1.22 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.--April 1967 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 8.45 ft (2.58 m) below land-surface datum, Dec. 10, 1970; lowest water level recorded, 49.18 ft (14.99 m) below land-surface datum, July 27, 1974. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 25.33 24.65 24.83 25.41 24.37 26.64 28.23 28.91 27.02 26.44 27.47 29.99 2 25.57 24.68 24.89 25.45 24.94 26.53 28.34 28.98 27.03 26.45 26.66 29.98 3 25.44 24.71 25.35 26.01 25.49 27.51 28.48 29.02 26.92 27.22 26.70 29.64 4 24.43 24.77 25.84 26.24 25.70 27.49 28.57 28.92 27.27 27.58 27.71 28.75 5 24.36 24.96 25.88 26.34 25.80 27.40 28.00 29.11 27.21 26.68 28.22 28.30 6 24.37 25.02 25.79 26.51 25.39 27.27 27.73 28.72 26.76 26.41 28.28 27.99 7 24.57 25.20 25.48 26.62 26.04 26.54 28.35 29.14 27.04 27.17 28.62 27.63 8 24.69 25.04 25.32 26.95 25.50 26.25 28.48 29.22 27.10 27.59 27.81 28.04 9 24.81 24.99 25.03 27.13 25.53 26.72 28.72 28.76 26.90 28.57 27.65 28.23 10 24.66 24.99 25.54 26.83 26.23 27.24 28.99 28.91 27.31 28.39 27.57 28.74 11 24.65 25.01 25.55 26.13 26.34 26.48 28.88 28.97 27.79 28.22 27.49 29.49 12 24.61 25.01 25.50 25.77 26.64 27.40 27.68 29.28 28.06 26.51 27.05 28.98 13 24.62 24.78 25.47 26.27 26.84 27.68 26.99 29.49 27.97 26.78 26.98 27.82 14 24.82 24.69 25.28 26.72 26.42 27.78 27.46 29.46 27.72 26.77 27.19 28.05 15 25.11 24.66 25.22 26.81 25.70 26.62 27.61 29.67 27.58 26.78 27.21 28.67 16 25.44 24.68 25.45 26.12 25.59 26.82 27.81 29.60 27.94 27.49 27.75 28.73 17 25.52 24.66 25.06 25.45 25.63 27.47 27.36 28.87 27.95 27.08 27.08 28.65 18 25.51 24.74 24.80 25.15 25.78 27.57 27.28 29.11 28.07 26.97 28.06 27.77 19 25.49 24.73 24.59 25.19 26.82 27.66 27.30 30.36 28.13 26.50 27.75 27.73 20 25.27 24.73 25.06 25.76 27.09 27.80 26.67 30.72 27.88 26.46 28.58 27.54 21 25.35 24.80 25.01 26.00 27.25 27.86 26.85 30.85 26.86 26.91 28.87 27.90 22 25.35 24.88 24.26 26.45 26.31 27.15 27.90 30.70 26.57 27.69 28.72 28.71 23 25.26 24.82 24.81 26.58 26.46 27.34 27.82 30.15 26.42 28.31 28.05 28.79 24 24.68 24.86 25.36 25.24 27.44 28.16 28.33 29.07 26.38 28.72 27,97 28.79 25 24.22 24.81 25.23 25.79 27.67 28.44 28.57 29.04 26.42 28.67 29.09 27.71 26 23.88 24.81 25.12 25.74 27.95 28.61 28.45 28.61 26.37 28.04 29.44 27.49 27 24.36 24.88 24.90 25.96 27.82 28.47 28.47 27.69 26.40 27.90 29.69 27.58 28 24.18 24.85 24.89 26.00 27.65 28.34 28.69 27.66 26.38 27.96 29.90 27.40 29 24.32 24.89 25.34 25.67 27.43 28.85 27.19 26.50 27.93 30.03 27.42 30 24.49 24.84 25.58 25.83 27.28 28.90 26.94 26.43 27.35 29.74 27.35 31 24.61 25.78 24.45 28.00 26.90 27.55 29.44 LOW 25.57 25.20 25.88 27.13 27.95 28.61 28.99 30.85 28.13 28.72 30.03 29.99 HIGH 23.88 24.65 24.26 24.45 24.37 26.25 26.67 26.90 26.37 26.41 26.66 27.35 WTR YR 1987 MEAN 26.9 LOW 30.85 HIGH 23.88 16 Lan wo 21 161 z4t 26 LJ >11) 31 I czz 36 ONDJ FMAMJJ ASONDJ FMAMJJ ASONDJ FMAMJJ AS 1984 1985 1986 1987 322 GROUND-WATER LEVELS RIO INABON TO RIO LOCO BASINS 180133066503300. Local number, 132. LOCATION.--Lat 18°01'33, long 66°5033. Owner: Pittsburg Plate Glass 4. Name: Yauco 2. AQUIFER.--Limestone of Tertiary Age. WELL 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-surface datum is about 75 ft (22.87 m) above mean sea level, from topographic map. Measuring point: 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 9.48 7.11 5.66 6.40 7.56 8.30 10.26 10.10 8.38 7.43 9.52 11.24 2 9.31 7.09 5.69 6.43 7.73 8.36 10.27 10.18 8.19 7.44 9.58 11.00 3 8.98 7.15 5.71 6.43 7.84 8.43 10.41 10.26 7.58 7.52 9.70 10.97 4 8.91 7.14 5.75 6.47 7.90 8.48 10.47 10.33 7.31 7.62 9.83 11.01 5 8.76 7.09 5.75 6.50 7.95 8.55 10.52 10.42 7.36 7.69 9.90 11.05 6 8.63 6.89 5.80 6.52 7.90 8.69 10.60 10.40 7.42 7.72 10.04 11.14 7 8.53 6.18 5.82 6.55 7.95 8.73 9.72 10.58 7.43 7.80 10.14 11.28 8 8.51 6.14 5.84 6.57 7.97 8.81 9.66 10.69 7.45 7.83 10.15 11.43 9 8.63 6.20 5.85 6.59 8.11 8.91 9.73 10.83 7.48 7.84 10.18 11.40 10 8.71 6.05 5.89 6.62 8.24 8.97 9.84 10.81 7.48 7.85 10.32 11.42 11 8.83 6.16 5.91 6.64 8.24 9.09 9.86 10.83 7.48 7.81 10.48 11.42 12 8.75 5.90 5.92 6.66 8.10 9.20 9.64 10.58 7.51 7.95 10.57 11.36 13 8.90 5.73 5.96 6.69 8.10 9.28 9.65 10.33 7.54 8.02 10.69 11.40 14 8.98 5.83 5.98 6.71 7.61 9.37 9.68 9.88 7.63 8.06 10.78 11.53 15 9.06 5.80 6.01 6.68 7.51 9.44 9.56 9.80 7.68 8.15 10.81 11.52 16 9.15 5.96 6.01 6.71 7.51 9.53 9.30 9.81 7.71 8.23 10.82 11.48 17 9.19 5.44 6.05 6.75 7.51 9.64 9.29 9.81 7.74 8.28 10.96 11.54 18 9.30 4.86 6.08 6.83 7.64 9.76 9.33 9.86 7.83 8.35 11.09 11.57 19 9.31 5.05 6.10 6.85 7.65 9.85 9.35 9.80 7.87 8.41 11.11 11.56 20 9.38 5.29 6.12 6.88 7.71 9.96 9.53 9.79 7.82 8.47 11.14 11.55 21 9.54 5.39 6.13 6.94 7.79 10.07 9.67 9.58 7.52 8.55 11.27 11.53 22 9.64 5.54 6.17 7.09 7.83 10.09 9.74 9.57 7.24 8.63 11.31 11.65 23 9.71 5,60 6.19 7.22 7.90 10.20 9.83 9.43 7.10 8.75 11.31 11.56 24 9.84 5.12 6.22 7.12 7.96 10.28 9.84 9.44 7.10 8.92 11.44 11.62 25 9.91 5.37 6.24 7.17 8.04 10.41 9.84 9.44 7.10 8.93 11.51 11.64 26 9.42 5.42 6.26 7.32 8.10 9.83 9.81 8.80 7.16 8.96 11.57 11.68 27 9.35 5.54 6.29 7.42 8.16 9.90 9.88 8.67 7.22 9.11 11.65 11.70 28 8.38 5.41 6.31 7.44 8.23 9.91 9.91 8.64 7.24 9.23 11.74 11.75 29 7.75 5.55 6.33 7.43 --- 9.94 9.95 8.58 7.35 9.31 11.57 11.81 30 7.15 5.62 6.36 7.61 10.06 10.04 8.55 7.42 9.43 11.24 11.94 31 7.08 --- 6.38 7.51 10.16 --- 8.54 --- 9.50 11.26 --- LOW 9.91 7.15 6.38 7.61 8.24 10.41 10.60 10.83 8.38 9.50 11.74 11.94 HIGH 7.08 4.86 5.66 6.40 7.51 8.30 9.29 8.54 7.10 7.43 9.52 10.97 WTR YR 1987 MEAN 8.57 LOW 11.94 HIGH 4.86 2 6 (`- ONDJFMAMJ J ASONDJFMAMJ J ASONDJFMAMJJ AS 1987 1984 1985 1986 + Above land-surface datum. GROUND-WATER LEVELS RIO GUANAJIBO BASIN 180132067033800. Local number, 143. LOCATION.--Lat 18°0132, long 67°0338. Owner: Pedro P. Vivoni. Name: Vivoni, Hacienda Amistad. AQUIFER.--Limestone of unknown age. WELL CHARACTERISTICS.--Drilled unused irrigation well, diameter 12 in (0.30 m). Depth 200 ft (60.98 m). DATUM.--Elevation of land-surface datum is about 52.5 ft (16.0 m) above mean sea level, from topographic map. Measuring point: Hole side of casing, 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-surface datum, Nov. 20, 1985; lowest water level recorded, 39.70 ft (12.10 m) below land-surface datum, June. 29, 1984. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 38.98 39.00 38.78 39.03 39.09 39.25 39.39 39.64 39.68 39.31 39.28 39.42 2 38.97 38.97 38.80 39.04 39.09 39.24 39.42 39.63 39.67 39.30 39.29 39.41 3 38.98 38.97 38.84 39.06 39.09 39.24 39.45 39.62 39.61 39.29 39.29 39.42 4 38.97 38.93 38.86 39.04 39.11 39.23 39.45 39.60 39.58 39.28 39.29 39.42 5 38.96 38.93 38.85 38.97 39.11 39.23 39.45 39.60 39.56 39.31 39.31 39.44 6 38.94 38.92 38.87 38.91 39.10 39.25 39.46 39.62 39.58 39.30 39.36 39.47 7 38.95 38.95 38.87 38.94 39.08 39.27 39.45 39.63 39.60 39.27 39.36 39.48 8 38.96 38.94 38.88 39.02 39.09 39.27 39.47 39.64 39.63 39.28 39.34 39.47 9 38.95 38.91 38.90 39.06 39.11 39.26 39.48 39.66 39.66 39.29 39.36 39.49 10 38.91 38.90 38.91 39.08 39.15 39.27 39.48 39.66 39.60 39.28 39.38 39.50 11 38.93 38.90 38.93 39.10 39.14 39.34 39.53 39.67 39.60 39.28 39.37 39.50 12 38.96 38.88 38.92 39.11 39.12 39.33 39.54 39.64 39.61 39.29 39.37 39.50 13 38.96 38.88 38.91 39.11 39.10 39.31 39.55 39.64 39.60 39.26 39.36 39.50 14 38.97 38.86 38.93 39.12 39.09 39.30 39.55 39.64 39.59 39.27 39.37 39.50 15 38.97 38.83 38.93 39.10 39.09 39.35 39.54 39.56 39.57 39.27 39.36 39.44 16 38.98 38.84 38.90 39.11 39.10 39.36 39.47 39.58 39.58 39.27 39.38 39.46 17 38.97 38.84 38.89 39.09 39.09 39.35 39.48 39.61 39.58 39.27 39.39 39.47 18 38.96 38.80 38.90 39.10 39.11 39.33 39.51 39.62 39.58 39.24 39.39 39.45 19 38.97 38.79 38.93 39.11 39.14 39.32 39.54 39.60 39.56 39.26 39.41 39.46 20 38.97 36.81 38.94 39.09 39.14 39.32 39.53 39.56 39.56 39.28 39.42 39.48 21 38.97 38.81 38.93 39.05 39.13 39.29 39.52 39.56 39.55 39.28 39.46 39.50 22 38.99 38.80 38.93 39.04 39.16 39.29 39.52 39.57 39.47 39.27 39.45 39.50 23 39.01 38.80 38.94 39.05 39.17 39.27 39.53 39.56 39.41 39.28 39.45 39.46 24 38.99 38.81 38.95 39.08 39.18 39.31 39.57 39.58 39.43 39.33 39.48 39.47 25 38.97 38.79 38.96 39.09 39.19 39.34 39.59 39.59 39.41 39.32 39.48 39.48 26 39.00 38.78 38.94 39.10 39.24 39.36 39.60 39.63 39.39 39.28 39.48 39.48 27 39.02 38.79 38.96 39.12 39.24 39.39 39.59 39.64 39.39 39.28 39.47 39.47 28 39.02 38.77 38.99 39.12 39.26 39.42 39.61 39.63 39.36 39.28 39.46 39.44 29 39.01 38.75 39.01 39.14 39.41 39.64 39.63 39.34 39.28 39.43 39.40 30 38.97 38.76 39.00 39.12 39.40 39.64 39.65 39.34 39.28 39.43 39.37 31 39.02 39.01 39.08 39.40 39.69 39.29 39.42 LOW 39.02 39.00 39.01 39.14 39.26 39.42 39.64 39.69 39.68 39.33 39.48 39.50 HIGH 38.91 38.75 38.78 38.91 39.08 39.23 39.39 39.56 39.34 39.24 39.28 39.37 WTR YR 1987 MEAN 39.3 LOW 39.69 HIGH 38.75 323 37 Lcioj b.."1 38 za >v? 39 etz 40 ONDJFMAMJJ ASONDJFMAMJJ ASONDJFMAMJJ AS 1984 1985 1986 1987 --- 324 GROUND-WATER LEVELS RIO CULEBRINAS BASIN 182018066593200. Local number, 83. LOCATION.--Lat 18°20'18", long 66°5932". Owner: P.R. Energy and Power Authority. Name: San Sebastian Well. AQUIFER.--San Sebastian Formation. WELL CHARACTERISTICS.--Drilled observation well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Depth 300 ft (91.4 m). DATUM.--Elevation of land-surface datum is about 230 ft (70.1 m) above mean sea level, from topographic map. Measuring point: 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.--Observation well. Automatic recorder installed on November 14, 1985. Formerly published as 182032066591800 PERIOD OF RECORD.--May 1967 to January 15, 1985. November 1985 to September 1987. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 21.95 ft (6.69 m) below land-surface 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-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INfTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP _ 1 28.95 27.17 28.67 28.94 29.40 29.16 29.82 28.48 29.64 28.04 2 28.97 27.25 28.09 28.97 29.39 29.18 29.65 28.36 29.76 28.09 3 29.03 27.34 28.07 28.99 29.37 29.20 29.68 27.98 --- 28.18 4 28.96 27.43 28.09 29.00 29.38 29.23 29.68 27.94 27.83 5 28.76 27.52 28.13 28.98 29.40 29.25 29.70 27.97 27.68 6 28.74 27.63 28.19 29.00 29.40 29.28 29.70 28.06 --- 27.70 7 28.78 27.73 28.26 29.04 29.40 29.31 29.72 28.11 28.12 27.74 8 28.52 27.78 28.12 29.05 29.42 29.33 29.40 28.15 28.16 27.79 9 28.47 27.82 28.38 29.06 29.45 29.35 29.37 28.13 28.24 27.88 10 28.26 27.92 28.44 29.06 29.48 29.36 29.37 28.16 28.31 27.88 11 28.29 27.98 28.51 29.08 29.37 29.40 29.40 28.21 28.35 27.72 12 28.10 28.06 28.53 29.10 29.04 29.43 28.91 28.22 28.42 27.50 13 28.11 28.08 28.59 29.12 28.89 29.44 28.78 28.40 28.46 27.48 14 28.17 28.13 28.62 29.13 28.86 29.46 28.70 28.44 28.31 27.52 15 28.20 28.19 28.65 29.15 28.65 29.49 28.31 28.49 28.29 27.57 16 28.18 28.24 28.68 29.18 28.63 29.50 28.08 28.55 28.06 27.66 17 28.20 28,21 28.12 29.19 28.66 29.53 27.83 28.62 28.07 27.71 18 28.21 28.24 28.75 29.21 28.71 29.52 27.79 28.66 28.12 27.76 19 27.84 28.18 28.79 29.24 28.76 29.55 27.84 28.44 27.93 27.84 20 27.58 28.20 28.83 29.25 28.80 29.56 27.88 28.42 27.71 27.92 21 27.58 28.24 28.84 29.25 28.83 29.58 27.92 28.47 27.72 27.96 22 27.64 28.28 28.88 29.27 28.90 29.60 28.02 28.52 27.75 28.01 23 27.68 28.33 28.92 29.31 28.93 29.62 28.08 28.52 27.80 28.04 24 27.62 28.39 28.95 29.33 28.99 29.66 28.16 28.59 27.89 28.09 25 27.61 28.43 28.98 29.34 29.04 29.69 28.23 28.64 27.97 28.18 26 27.67 28.46 29.00 29.37 29.09 29.71 28.28 28.60 29.45 28.01 28.25 27 27.26 28.52 29.03 29.40 29.10 29.73 28.32 28.63 29.51 27.79 28.29 28 27.08 28.57 29.06 29.41 29.15 29.76 28.39 28.60 29.59 27.79 28.33 29 27.08 28.58 28.89 29.42 --- 29.78 28.47 28.64 29.58 27.85 28.35 30 27.10 28.63 28.86 29.40 29.79 28.49 28.52 29.60 27.93 28.39 31 27.13 --- 28.90 29.38 29.83 --- --- --- 27.99 LOW 29.03 28.63 29.06 29.42 29.48 29.83 29.82 28.39 HIGH 27.08 27.17 28.07 28.94 28.63 29.16 27.79 27.48 24 Lcga trli 26 z 28 30 32 NDJFMAMJJ ASONDJ FMAMJJ AS 1985 1986 1987 325 GROUND-WATER LEVELS RIO CULEBRINAS BASIN 182442067091700. Local number, 200 . LOCATION.--Lat 18°2442, long 67°0917". Owner: Carmelo Sanchez Name: Aguadilla Cement Well. AQUIFER.--Surficial deposits. WELL CHARACTERISTICS.--Abandoned water-table industrial well, diameter 4 in (0.10 m), cased 0-20 ft (0-6.10 m), perforated 11-20 ft (3.35-6.10 m). Deoth 20 ft (6.10 m). DATUM.--Elevation of land-surface datum is about 10 ft (3.05 m) above mean sea level, from topographic map. Measuring point: Shelter floor on top of 4 in (0.10 m) casing, 3.25 ft (0.99 m) above land-surface datum. REMARKS.--Observation well. Automatic recorder installed on November 1985. Water levels affected by nearby pumping well. Estimated noon values: Nov. 19-Dec 5. PERIOD OF RECORD.--October 1985 to September 1987. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 2.85 ft (0.87 m) below land-surface datum. May 14, 1986; lowest water level recorded, 8.46 ft (2.58 m) below land-surface datum, Apr. 17, 1986, WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 7.00 5.54 6.86 7.02 7.50 7.76 7.97 7.02 7.98 5.56 6.32 6.27 2 7.01 5.62 5.87 7.02 7.46 7.79 7.90 7.69 7.98 5.69 6.37 6.32 3 7.01 5.71 5.71 7.03 7.45 7.81 7.93 7.47 7.98 5.79 6.11 6.37 4 7.02 5.73 5.83 7.03 7.51 7.83 7.95 7.58 7.75 5.61 5.88 6.03 5 6.63 5.82 6.00 7.03 7.53 7.85 7.77 7.63 7.75 5.77 6.02 5.61 6 6.73 5.89 6.09 7.20 7.55 7.86 7.54 7.66 7.55 5.84 6.17 5.75 7 6.81 5.96 6.20 6.96 7.57 7.43 7.65 7.71 7.37 6.04 6.26 5.26 8 6.88 6.00 6.25 7.00 7.59 7.51 7.71 7.69 7.47 6.13 6.30 5.53 9 6.62 6.00 6.32 7.08 7.63 7.60 7.16 7.43 7.33 6.25 6.34 5.59 10 6.58 6.07 6.35 7.13 7.65 7.66 7.80 7.46 7.40 5.97 6.45 4.94 11 6.67 6.15 6.42 7.18 7.15 7.72 7.80 7.44 7.47 6.03 6.51 4.99 12 6.55 6.13 6.47 7.22 6.85 7.76 7.80 7.23 7.58 6.12 6.55 4.87 13 6%65 6.20 6.52 7.25 6.97 7.81 7.45 7.40 7.53 6.24 6.67 4.96 14 6.62 6.26 6.57 7.28 7.06 7.84 7.44 7.51 7.29 6.30 6.64 5.20 15 6.74 6.32 6.53 7.29 7.12 7.74 7.19 7.58 7.34 6.33 6.64 5.28 16 6.37 6.35 6.60 7.33 7.22 7.83 7.25 7.57 7.05 6.36 6.34 5.43 17 6.46 6.40 6.64 7.33 7.30 7.33 7.32 7.63 6.48 6.41 6.49 5.47 18 6.57 6,45 6.67 7.35 7.36 7.31 7.38 7.68 6.32 6.43 6.60 5.54 19 5.99 6.48 6.73 7.37 7.42 7.39 7.43 7.73 6.37 6.41 6.68 5.55 20 5.95 6.54 6.76 7.39 7.47 7.48 7.49 7.67 6.31 6.37 6.27 5.63 21 6.02 6.58 6.79 7.40 7.52 7.55 7.56 7.73 6.43 6.44 5.76 5.77 22 5.88 6.61 6.83 7.42 7.56 7.62 7.68 7.73 6.28 6.50 5.82 5.79 23 6.01 6.65 6.86 7.43 7.60 7.68 7.77 7.73 6.19 6.51 5.94 5.79 24 5.00 6.67 6.88 7.44 7.66 7.72 7.85 7.75 6.30 6.24 6.11 5.81 25 4.97 6.72 6.90 7.45 7.69 7.76 7.92 7.83 6.39 6.29 6.21 5.96 26 5.04 6.75 6.93 7.47 7.72 7.80 7.99 7.82 6.37 6.33 6.28 5.94 27 5.00 6.77 6.94 7.49 7.73 7.84 7.92 7.84 6.10 6.37 6.01 5.97 28 5.06 6.80 6.98 7.51 7.75 7.86 7.99 7.80 6.18 5.98 6.06 6.06 29 5.24 6.82 6.99 7.50 --- 7.89 7.64 7.85 5.81 6.07 6.12 6.10 30 5.32 6.83 7.00 7.41 7.92 7.68 7.85 5.44 6.14 6.22 5.81 31 5.44 --- 7.01 7.46 7.95 --- 7.87 --- 6.26 6.27 --- LOW 7.02 6.83 7.01 7.51 7.75 7.95 7.99 7.87 7.98 6.51 6.68 6.37 HIGH 4.97 5.54 5.71 6.96 6.85 7.31 7.19 7.02 5.44 5.56 5.76 4.87 WTR YR 1987 MEAN 6.81 LOW 7.99 HIGH 4.87 3 91 2 lalj I-- < 4 w La 0 c, z 6 6 _It "441\ijr)\ w 8 vila iz z 1=1-< 10 • 3 NDJ FM AMJJ ASONDJ FM AMJ J AS 1985 1986 1987 326 THIS PAGE WAS LEFT BLANK INTENTIONALLY Surface- Water Records for U.S. Virgin Islands 328 THIS PAGE WAS LEFT BLANK INTENTIONALLY 329 ST. THOMAS, U.S. VIRGIN ISLANDS 50252000 BONNE RESOLUTION GUT AT BONNE RESOLUTION, ST. THOMAS, VI LOCATION.--Lat 18°2157", long 64'57'34", Hydrologic Unit 21020001, on right bank near Hull Bay Road, 0.5 ml (0.8 km) upstream from Atlantic Ocean. and 2.5 mi (4.02 km) northwest of Fort Christian, Charlotte Amalie. DRAINAGE AREA.--0.49 mi? (1.27 km?). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--December 1962 to February 1967, March 1979 to April 1981, May 1982 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 280 ft (85 m), from topographic map. December 1962 to February 1967 at site about 100 ft (30 m) downstream at different datum. March 1979 to April 1981 at site about 100 ft (30 m) upstream at different datum. REMARKS.--Records poor. AVERAGE DISCHARGE.--9 years (1964-66, 1980, 1983-87), 0.30 ft2/s (0.008 m 3/s), 8.31 in/yr (211 mm/yr), 217 acre-ft/yr (0.268 he/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 1,650 ft'/s (46.7 m'is), Apr. 18, 1983, gage height, 7.00 ft (2.134 m), from floodmarks, from rating curve extended above 1,0 ft'is (0.03 m'/s) 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 ft'is (1.42 e/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft'/s) (m 3/s) (ft) (m) Date Time (W/s) (e/s) (ft) (m) Nov. 16 1445 168 4.76 2.29 0.698 May 24 1415 368 10.4 3.27 0.997 Nov. 17 1815 178 5.04 2.35 0.716 May 25 1415 86 2.44 1.75 0.533 Mar. 17 0615 90 2.55 1.78 0.542 May 29 1800 *527 14.9 *3.90 1.189 May 6 1145 103 2.92 1.88 0.573 June 22 0215 356 10.1 3.22 0.981 Minimum daily disharge, 0.01 ft'is (0.0003 10/s), Jan. 12-14, 21, Feb. 12-18 and Mar. 4-9. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .07 .13 .03 .07 .03 .04 .07 .02 .18 .12 .07 .05 2 .02 .05 .09 .08 .04 .03 .07 .02 .27 .09 .08 .11 3 .02 .12 .05 .09 .04 .03 .07 .02 2.7 .07 .10 .11 4 .02 .09 .03 .07 .03 .10 .07 .03 .58 .07 .18 .05 5 .03 .17 .03 .08 .03 .01 .16 .13 .18 .07 .06 .07 6 .03 1.4 .05 .30 .03 .01 .05 6.7 .12 .08 .04 .08 7 .04 .74 .07 .17 .05 .01 .05 .36 .09 .09 .04 .10 8 .05 1.1 .03 .05 .05 .01 .05 .10 .07 .06 .04 .15 9 .09 .30 .03 .03 .06 .02 .04 .07 .06 .06 .03 .11 10 .07 .18 .04 .02 .07 .03 .03 .36 .07 .06 .04 .04 11 .06 .15 .03 .02 .09 .07 .73 .17 .07 .06 .05 .06 12 .04 .10 .03 .02 .02 .08 1.4 .74 .05 .05 .07 .09 13 .02 .08 .07 .01 .02 .06 .30 .13 .05 .07 .04 .11 14 .02 .09 .13 .10 .02 .06 .43 .08 .06 .07 .05 .11 15 .04 .17 .05 .04 .01 1.5 .18 .06 .10 .09 .17 .11 16 .04 15 .02 .03 .01 .28 .10 .05 .06 .07 .08 .16 17 .02 18 .03 .02 .01 6.3 .08 .48 .06 .07 .06 .19 18 .02 1.7 .03 .02 .02 .26 .06 .11 .05 .07 .05 .05 19 .04 .35 .03 .02 .02 .10 .05 3.3 .10 .06 .06 .05 20 .03 .19 .04 .03 .02 .08 .05 .23 .66 .06 .06 .06 21 .06 .13 .06 .02 .03 .06 .05 .30 4.5 .06 .08 .07 22 .02 .11 .06 .02 .03 .06 .04 2.5 15 .05 .05 .06 23 .03 .07 .06 .02 .03 .08 .04 .61 .42 .06 .06 .04 24 .03 .06 .08 .02 .03 .08 .04 14 .24 .C6 .08 .11 25 .07 .05 .09 .02 .03 .07 .04 9.4 .16 .06 .10 .14 26 .29 .05 .13 .02 .02 .06 .04 2.0 .13 .05 .09 .18 27 .08 .08 .06 .02 .02 .05 .04 .32 .11 .05 .10 .23 28 .07 .04 .06 .02 .03 .04 .09 .20 .11 .05 .05 .09 29 .08 .03 .06 .02 --- .05 .05 20 .37 .05 .06 .06 30 .06 .04 .06 .03 .05 .03 .99 .17 .06 .07 .05 31 .05 --- .06 .04 .06 --- .24 --- .07 .11 --- TOTAL 1.61 40.77 1.69 1.52 0.89 9.74 4.50 63.72 26.79 2.06 2.22 2.89 MEAN .052 1.36 .055 .049 .032 .31 .15 2.06 .89 .066 .072 .096 MAX .29 18 .13 .30 .09 6.3 1.4 20 15 .12 .18 .23 MIN .02 .03 .02 .01 .01 .01 .03 .02 .05 .05 .03 .04 AC-FT 3.2 81 3.4 3.0 1.8 19 8.9 126 53 4.1 4.4 5.7 CFSM .11 2.77 .11 .10 .06 .64 .31 4.19 1.82 .14 .15 .20 IN. .12 3.10 .13 .12 .07 .74 .34 4.84 2.03 .16 .17 .22 CAL YR 1986 TOTAL 101.17 MEAN .28 MAX 18 MIN .00 AC-FT 201 CFSM .57 IN. 7.68 WTR YR 1987 TOTAL 158.40 MEAN .43 MAX 20 MIN .01 AC-FT 314 CFSM .89 IN. 12.03 330 ST. THOMAS, U.S. VIRGIN ISLANDS 50276000 TURPENTINE RUN AT MARIENDAL, ST. THOMAS, VI LOCATION.--Lat 18°19'48'. long 64*52'58'. Hydrologic Unit 21020001. on right bank, at Mariendal. 1.0 mi (1.6 km) upstream from mouth, and 3.3 mi (5.3 km) southeast of Fort Christian, Charlotte Amalie. DRAINAGE AREA.--2.97 0' (7.69 km2 ). WATER-DISCHARGE RECORDS PERIOD OF KCORD.--January 1963 to April 1969, October 1978 to September 1980, June 1982 to July 1986, July to Sept. 1987 (high-water discharges only). GAGE.--Crest-stage gage. Elevation of gage is 40 ft (12 m). from topographic map. REMARKS. --Records poor, peak discharge only. AVERAGE DISCHARGES.--10 years (1964-68. 1979-80. 1983-85), 1.22 ft'/s (0.034 m 3 /s), 5.58 in/yr (142 mm/yr). 884 acre-ft/yr (1.09 hiP/yr); median of yearly mean discharges. 0.54 ft'is (0.015 mYs), 390 acre-ft/yr (0.48 he/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 9,710 ft'/s (275 e/s), Apr. 18. 1983, gage height, 11.09 ft (3.380 m), from floodmark, from rating curve extended above 500 ft'/s (14.2 s'/s) 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 ft'/s (2.83 43/s) and maximum (*): Discharge Gage height Discharge Gage height Date The (W/s) (10/s) (ft) (m) Date Time (W/s) (10/s) (ft) (m) Nov. 16 0745 194 5.49 3.09 0.942 May 6 0945 *493 14.0 *4.4o 1.359 ST. JOHN, U.S. VIRGIN ISLANDS 331 50295000 GUINEA GUT AT BETHANY. ST . JOHN, VI LOCATION.--Lat. 18'19'55". long 64°46'50". Hydrologic Unit 21020001. 600 ft (183 m) southeast of Bethany Church. and 1.0 mi (1.6 km) east of Government House at Cruz Bay. DRAINAGE AREA.--0.37 mi 2 (0.96 km2 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1963 to October 1967. September 1982 to current year. GAGE.--Water-stage recorder and concrete control. Elevation of gage is 260 ft (79 4). from topographic map. Prior to September 1982, at datum 1.00 ft (0.30 m) higher. REMARKS.--Records poor. AVERAGE DISCHARGE.--9 years (1964-67, 1983-87), 0.09 ft'is (0.002 e/s), 3.27 in/yr (83 mm/yr), 64.48 acre-ft/yr (0.080 hm3 /yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 946 ft'/s (26.8 m'/s). Apr. 18. 1983, gage height, 5.33 ft (1.625 m), from floodmark, from rating curve extended above 1.0 ft'is (0.028 e/s) on basis of step-backwater analysis and slope-area measurement of peak flow; no flow many days each year. EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 10 ft 7 /s (0.283 10/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (ft'/s) (10/s) (ft) (m) Date Time (W/s) (m0/s) (ft) (m) Nov. 17 1630 *43 1.22 *2.41 0.734 No flow many days. DISCHARGE, CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .06 .02 .00 .00 .01 .01 .00 .00 .00 .00 .00 .00 2 .06 .02 .00 .00 .01 .01 .00 .00 .00 .00 .01 .00 3 .06 .02 .00 .00 .01 .01 .00 .00 .70 .00 .01 .00 4 .05 .02 .00 .00 .01 .02 .00 .00 .14 .00 .01 .00 5 .05 .02 .00 .00 .02 .01 .00 .00 .02 .00 .01 .00 6 .04 .02 .00 .00 .02 .01 .00 .01 .01 .00 .01 .00 7 .04 .02 .00 .00 .01 .00 .01 .00 .00 .00 .01 .00 s .03 .01 .00 .00 .01 .01 .00 .00 .00 .00 .01 .00 9 .04 .01 .00 .00 .01 .01 .00 .00 .00 .00 .01 .00 10 .04 .01 .00 .00 .01 .00 .00 .00 .00 .00 .01 .00 11 .04 .01 .00 .00 .01 .01 .00 .01 .00 .00 .01 .01 12 .04 .01 .00 .00 .01 .00 .00 .01 .00 .00 .01 .00 13 .04 .01 .00 .00 .01 .00 .00 .01 ,00 .00 .01 .00 14 .03 .01 .00 .00 .01 .00 .00 .01 .00 .00 .00 .00 15 .03 .01 .00 .00 .01 .00 .00 .00 .00 .00 .00 .00 16 .04 .51 .00 .00 .01 .01 .00 .00 .00 .00 .00 .00 17 .05 2.8 .00 .00 .01 .01 .01 .00 .00 .00 .00 .00 18 .04 .39 .00 e.00 .01 .01 .01 .00 .00 .00 .00 .00 19 .03 .04 .00 e.00 .01 .01 .01 .00 .00 .00 .00 .00 20 .03 .01 .00 e.00 .01 .00 .01 .00 .01 .00 .00 .00 21 .06 .01 .00 e.00 .01 .00 .00 .01 .03 .00 .00 .01 22 .05 .00 .00 e.01 .01 .00 .00 .00 .02 .00 .00 .01 23 .05 .00 .00 .01 .01 .00 .00 .00 .00 .00 .00 .00 24 .05 .00 .00 .01 .01 .00 .00 .02 .00 .00 .00 .00 25 .05 .00 .00 .01 .01 .00 .00 .11 .00 .00 .00 .00 26 .05 .09 .00 .01 .01 .00 .00 .05 .00 .00 .00 .00 27 .05 .09 .00 .01 .01 .00 .00 .01 .00 .00 .00 .00 28 .04 .00 .00 .01 .01 .00 .00 .00 .00 .00 .00 .00 29 .04 .00 .00 .01 --- .00 .00 .00 .00 .00 .00 .01 30 .03 .00 .00 .01 .00 .00 .00 .00 .00 .00 .00 31 .03 --- .00 .02 .00 --- .00 --- .00 .00 TOTAL 1.34 4.16 0.00 0.11 0.30 0.14 0.05 0.25 0.93 0.00 0.12 0.04 MEAN .043 .14 .00 .004 .011 .005 .002 .008 .031 .00 .004 .001 MAX .06 2.8 .00 .02 .02 .02 .01 .11 .70 .00 .01 .01 MIN .03 .00 .00 .00 .01 .00 .00 .00 .00 .00 .00 .00 AC-FT 2.7 8.3 .o .2 .6 .3 .1 .5 1.8 .0 .2 .08 CFSM .12 .37 .00 .01 .03 .01 .00 .02 .08 .00 .01 .00 IN. .13 .42 .00 .01 .03 .01 .01 .03 .09 .00 .01 .00 CAL YR 1986 TOTAL 41.52 MEAN .11 MAX 9.3 MIN .00 AC-FT 82 CFSM .31 IN. 4.17 WTR YR 1987 TOTAL 7.44 MEAN .020 MAX 2.8 MIN .00 AC-FT 15 CFSM .06 IN. .75 e Estimated ST. CROIX, U.S. VIRGIN ISLANDS 332 50345000 JOLLY HILL GUT AT JOLLY HILL, ST. CROIX, VI LOCATION.--Lat 17'4400", 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 2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1963 to December 1968. Monthly measurements, 1962, 69. October 1982 to current year. GAGE.--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. AVERAGE DISCHARGE.--10 years (1964-68. 1983-87). 0.116 ft'/s (0.003 al's), 0.75 in/yr (19.0 mm/yr), 84.0 acre-ft/yr (0.10 hm 3/yr); median of yearly mean discharges, 0.04 ft'/s (0.001 10/s), 29.0 acre-ft/yr (0.04 hie/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge. 349 ft'/s (9.884 a'/s). June 20, 1987, gage height, 3.86 ft (1.176 m); 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 (*): Discharge Gage height Discharge Gage height Date Time (ft'/s) (10/s) (ft) (m) Date Time (ft'/s) (10/s) (ft) (m) June 20 2230 *349 9.88 *3.86 1.176 No flow many days. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 MEAN VALUES BAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .00 .00 e.03 e.03 .04 .01 .01 .00 .02 1.0 .31 .10 2 .00 .00 e.04 e.03 .05 .01 .01 .00 .05 1.2 .30 .10 3 .00 .00 e.06 e.03 .05 .01 .01 .00 .43 1.2 .29 .10 4 .00 .00 e.03 e.03 .05 .01 .01 .00 .11 .99 .29 .10 5 .00 .00 e.03 e.04 .05 .01 .01 .00 .06 .78 .28 .10 6 .00 .00 e.03 e.05 .05 .01 .01 .00 .06 .45 .23 .10 7 .00 .00 e.05 e.04 .05 .01 .01 .00 .06 e.39 .22 .10 8 .00 .02 e.03 e.03 .04 .01 .01 .00 .06 e.64 .23 .07 9 .00 e.02 e.03 e.03 .04 .01 .00 .00 .12 .55 .24 .07 10 .00 e.03 e.04 e.03 .06 .01 .00 .00 .10 .64 .18 .07 11 .00 e.02 e.07 e.03 .04 .01 .00 .00 .10 .64 .18 .07 12 .00 e.07 e.03 e.03 .04 .01 .00 .00 .12 e.85 .18 .07 13 .00 e.03 e.03 e.03 .05 .00 .01 .00 .13 .48 .18 .07 14 .00 e.04 e.03 e.03 .06 .00 .02 .00 .13 .49 .18 .07 15 .00 e.03 e.03 e.03 .06 .00 .01 .00 .16 .46 .18 .07 16 .00 e.04 e.03 e.03 .06 .00 .01 .00 .16 .42 .18 .07 17 .00 e.03 e.03 e.03 .07 .03 .00 .00 .16 .39 .17 .07 18 .00 e.03 e.03 e.03 .05 .02 .00 .00 .16 .39 .16 .12 19 .00 e.03 e.03 e.03 .05 .02 .00 .00 .18 .39 .16 .10 20 .00 e.02 e.03 e.03 .04 .01 .00 .01 12 .37 .15 .08 21 .00 e.02 e.03 .03 .04 .01 .00 .02 11 .37 .13 .08 22 .00 e.02 e.03 .03 .03 .01 .00 .00 5.0 .36 .13 .08 23 .00 e.02 e.03 .04 .01 .01 .00 .00 2.6 .34 .13 .08 24 .00 e.02 e.03 .04 .01 .01 .00 .05 2.0 .33 .12 .08 25 .00 e.08 e.06 .03 .01 .09 .00 .12 1.6 .33 .11 .08 26 .00 e.05 e.04 .03 .01 .07 .00 .12 1.4 .30 .11 .08 27 .00 e.04 e.04 .03 .01 .04 .00 .05 1.3 .26 .11 .08 28 .00 e.03 e.04 .03 .01 .03 .00 .04 1.2 .26 .11 .08 29 .00 e.03 e.03 .03 --- .02 .00 .03 1.2 .26 .10 .08 30 .00 e.03 e.03 .03 .02 .00 .02 1.1 .26 .10 .07 31 .00 --- e.03 .05 .01 --- .02 --- .30 .10 --- TOTAL 0.00 0.75 1.10 1.01 1.13 0.52 0.13 0.48 42.77 16.09 5.54 2.49 MEAN .00 .025 .035 .033 .040 .017 .004 .015 1.43 .52 .18 .083 MAX .00 .08 .07 .05 .07 .09 .02 .12 12 1.2 .31 .12 MIN .00 .00 .03 .03 .01 .00 .00 .00 .02 .26 .10 .07 AC-FT .0 1.5 2.2 2.0 2.2 1.0 .3 1.0 85 32 11 4.9 CFSM .00 .01 .02 .02 .02 .01 .00 .01 .68 .25 .09 .04 IN. .00 .01 .02 .02 .02 .01 .00 .01 .76 .29 .10 .04 CAL YR 1986 TOTAL 42.00 MEAN .12 MAX 1.1 MIN .00 AC-FT 83 CFSM .05 IN. .74 WTR YR 1987 TOTAL 72.01 MEAN .20 MAX 12 MIN .00 AC-FT 143 CFSM .09 IN. 1.28 e Estimated Ground-Water Records for U.S. Virgin Islands 334 THIS PAGE WAS LEFT BLANK INTENTIONALLY 335 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174225064471900. Local number. 1. LOCATION.--Lat 17°42'25", long 64°47'19". Owner: Virgin Islands Government. Name: Fairplains 6 (FP6). AQUIFER.--Alluvium and marl. WELL CHARACTERISTICS.--Drilled public supply 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 point: Top of pump concrete base, 2.20 ft (0.67 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, 15.64 ft (4.77 m) below land-surface datum, Mar. 25, 1982; lowest water level measured, a58.57 ft (17.9 m) below land-surface datum, June 20, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 20 17.19 Apr. 27 a56.24 June 17 17.72 a Pumping. __ GROUND-WATER LEVELS 336 ST. CROIX, U.S. VIRGIN ISLANDS 174225064472000. Local number, 2. LOCATION.--Lat 17°42 1 25", long 64°47'20. Owner: U.S. Government, Virgin Islands Government. Name: USGS-10, Fairplains 2 (FP2). AQUIFER.--Alluvium and marl. WELL 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 point: Top of 0.5 in (0.01 a) hole at concrete base wall, 3.00 ft (0.91 m) above land-surface datum. REMARKS.--Recording observation well. Nearby pumping well. PERIOD OF RECORD.--June 1983 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 20.91 ft (6.37 m) below land-surface datum, Nov. 27, 29, 1985; lowest water level recorded, 25.02 ft (7.63 a) below land-surface datum, Aug. 22, 1984. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 23.84 23.18 22.00 21.87 23.98 23.38 21.72 21.64 22.33 2 23.87 23.18 22.05 21.86 23.98 23.38 21.68 21.56 22.34 3 23.91 23.19 22.04 21.85 23.96 23.39 21.66 21.56 22.35 4 23.94 23.11 22.03 21.87 23.94 23.32 21.69 21.57 22.36 5 23.95 23.10 22.03 21.88 23.94 23.28 21.67 21.56 22.40 6 23.96 23.05 22.01 21.88 23.94 23.26 21.64 21.62 22.44 7 24.00 23.01 21.97 21.89 23.94 23.24 21.62 21.74 22.47 8 24.07 22.93 21.94 21.91 23.94 23.24 21.61 21.72 22.56 9 24.10 22.85 21.92 21.93 23.89 23.22 21.52 21.68 22.32 10 24.11 22.72 21.97 21.93 23.88 23.19 21.49 21.65 22.20 11 24.13 22.72 22.01 21.92 23.88 22.93 21.49 21.70 22.20 12 24.13 22.72 22.03 21.97 23.88 22.83 21.51 21.75 22.23 13 24.12 22.63 22.04 21.99 23.83 22.74 21.52 21.76 22.22 14 24.11 22.75 22.01 21.96 23.80 22.69 21.58 21.81 22.26 15 24.10 22.71 21.99 21.90 23.79 22.64 21.48 21.92 22.27 16 24.11 22.65 21.96 21.87 23.81 22.54 21.45 21.81 22.36 17 24.12 22.60 21.96 21.86 23.79 22.50 21.45 21.82 22.35 18 24.12 22.54 21.95 21.89 23.82 22.41 21.42 21.65 22.43 19 24.15 22.42 21.90 21.87 23.84 22.40 21.36 21.62 22.71 20 24.12 22.34 21.95 --- 23.82 22.37 21.32 21.59 22.78 21 24.20 22.29 21.91 23.78 22.18 21.28 21.87 22.84 22 24.23 22.22 21.84 23.71 22.01 21.30 21.86 22.92 23 24.20 22.17 21.93 23.66 21.94 21.34 21.84 22.96 24 24.19 22.22 21.97 23.63 21.98 21.37 21.90 22.86 25 24.18 22.24 21.95 23.61 21.95 21.35 21.97 22.86 26 23.97 22.19 21.92 23.47 21.91 21.32 22.05 22.86 27 23.63 22.12 21.93 --- 23.44 21.85 21.32 22.02 22.86 28 23.47 22.06 22.02 23.95 23.45 21.81 21.33 22.22 22.97 29 23.38 22.08 21.96 24.01 23.44 21.79 21.34 22.23 23.06 30 23.31 22.04 21.91 24.03 23.42 21.74 21.38 22.25 23.10 31 23.25 --- 21.91 --- 23.39 --- 21.42 22.29 --- LOW 24.23 23.19 22.05 23.98 23.39 21.72 22.29 23.10 HIGH 23.25 22.04 21.84 23.39 21.74 21.28 21.56 22.20 20 ONDJFMAMJJASONDJFMAMJJASONDJ__FMAMJJAS 22 : VAir4.464v.iWisi 1/r af- ..4 24 26 1984 1985 1986 ••••••••• 337 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174243064475100. Local number, 3. LOCATION.--Lat 17°42 1 43", long 64°4751". Owner: U.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, 14.76 ft (4.50 m) below land-surface datum, Mar. 25, 1982; lowest water level recorded, 29.27 ft (8.90 m) below land-surface datum, May 30-31, June 1-5, 1987. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 28.20 28.61 27.38 27.60 28.01 28.40 28.77 29.05 29.27 17.40 22.24 24.91 2 28.21 28.62 27.40 27.62 28.03 28.41 28.78 29.05 29.27 17.48 22.38 24.98 3 28.22 28.62 27.42 27.64 28.04 28.42 28.79 29.06 29.27 17.54 22.52 25.03 4 28.23 28.63 27.43 27.65 28.05 28.44 28.79 29.07 29.27 17.61 22.61 25.08 5 28.24 28.64 27.44 27.66 28.06 28.46 28.80 29.07 29.18 17.74 22.76 25.14 6 28.26 28.64 27.45 27.67 28.07 28.47 28.81 29.07 28.91 17.81 22.87 25.20 7 28.28 28.65 27.46 27.68 28.08 28.49 28.82 29.08 28.69 17.91 22.96 25.25 8 28.29 28.66 27.46 27.70 28.08 28.50 28.83 29.08 28.54 18.05 23.04 25.31 9 28.31 28.66 27.47 27.73 28.09 28.52 28.84 29.08 28.44 18.19 23.19 25.34 10 28.33 28.67 27.47 27.74 28.10 28.53 28.85 29.11 28.35 18.34 23.26 25.38 11 28.34 28.67 27.47 27.75 28.10 28.55 28.86 29.13 28.27 18.50 23.35 25.41 12 28.36 28.67 27.47 27.76 28.11 28.57 28.87 29.14 28.21 18.67 23.46 25.45 13 28.38 28.67 27.47 27.76 28.12 28.58 28.88 29.15 28.16 18.85 23.56 25.51 14 28.39 28.67 27.48 27.77 28.13 28.60 28.89 29.16 28.13 19.03 23.63 25.55 15 28.40 28.67 27.48 27.77 28.15 28.61 28.90 29.17 28.10 19.24 23.72 25.58 16 28.42 28.67 27.48 27.78 28.17 28.62 28.90 29.18 28.08 19.44 23.80 25.63 17 28.43 28.67 27.48 27.79 28.18 28.64 28.91 29.18 28.07 19.65 23.87 25.67 18 28.45 28.47 27.48 27.80 28.20 28.65 28.92 29.19 28.07 19.86 23.94 25.68 19 28.46 28.20 27.49 27.81 28.22 28.67 28.93 29.20 28.08 20.11 24.03 25.70 20 28.48 28.01 27.49 27.83 28.23 28.68 28.94 29.20 28.10 20.29 24.10 25.73 21 28.50 27.87 27.50 27.83 28.25 28.69 28.95 29.21 27.49 20.49 24.18 25.76 22 28.51 27.79 27.50 27.85 28.28 28.71 28.96 29.22 25.02 20.66 24.23 25.81 23 28.52 27.68 27.50 27.87 28.29 28.71 28.97 29.23 22.08 20.86 24.30 25.83 24 28.54 27.61 27.51 27.89 28.31 28.72 28.98 29.23 20.03 21.09 24.40 25.89 25 28.55 27.55 27.51 27.90 28.33 28.73 28.99 29.24 18.74 21.24 24.47 25.92 26 28.56 27.49 27.52 27.92 28.35 28.73 29.00 29.25 18.06 21.40 24.55 25.94 27 28.57 27.46 27.53 27.94 28.37 28.74 29.01 29.25 17.72 21.54 24.61 25.96 28 28.58 27.40 27.53 27.95 28.39 28.75 29.02 29.26 17.51 21.69 24.66 25.98 29 28.59 27.37 27.57 27.96 28.75 29.03 29.26 17.40 21.83 24.74 25.99 30 28.60 27.38 27.58 27.98 28.76 29.04 29.26 17.38 21.97 24.80 26.03 31 28.61 27.59 27.99 28.77 29.27 22.11 24.87 LOW 28.61 28.67 27.59 27.99 28.39 28.77 29.04 29.27 29.27 22.11 24.87 26.03 HIGH 28.20 27.37 27.38 27.60 28.01 28.40 28.77 29.05 17.38 17.40 22.24 24.91 WTR YR 1987 MEAN 26.8 LOW 29.27 HIGH 17.38 17 (DR 20 zrzi 23 26 >v) Jc 29 32 ONDJFMAMJJ ASONDJFMAMJJ ASONDJFMAMJJ AS 1984 1985 1986 1987 338 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174245064475800. Local number, 4. LOCATION.--Lat 17°4245, long 64°47'58". Owner: Virgin Islands Government. Name: Golden Grove - 1 (PW1). AQUIFER.--Alluvium and marl. WELL CHARACTERISTICS.--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). 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 RECORD: Highest water level measured, 23.09 ft (7.04 m) below land-surface datum, May 18 1983: 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 20 a54.06 Apr. 27 a54.65 June 17 a57.23 a Pumping. 339 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174303064484400. Local number, 6. LOCATION.--Lat 17°43'03, long 64°4844. Owner: U.S. Government, Virgin Islands Government. Name: 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 point: 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 recorded, 24.90 ft (7.59 m) below land-surface datum, Mar. 25, 1982: 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 37.54 38.07 36.19 35.65 35.96 36.10 36.44 37.19 37.27 33.67 34.82 36.74 2 37.55 38.07 35.95 35.66 35.96 36.12 36.47 37.22 37.23 33.71 34.87 36.74 3 37.58 38.08 36.09 35.68 35.96 36.13 36.50 37.26 37.05 33.75 34.92 36.81 4 37.61 38.09 35.96 35.69 35.96 36.14 36.52 37.28 36.80 33.78 34.95 36.88 5 37.62 38.09 35.86 35.68 35.95 36.15 36.53 37.30 36.92 33.84 34.97 36.78 6 37.65 38.09 35.80 35.67 35.94 36.17 36.55 37.32 36.92 33.88 35.04 37.01 7 37.66 38.07 35.74 35.69 35.94 36.18 36.55 37.32 36.79 33.90 35.09 37.05 8 37.69 38.03 35.71 35.72 35.94 36.18 36.56 37.33 36.67 33.94 35.13 37.12 9 37.71 38.03 35.68 35.73 35.97 36.19 36.57 37.35 35.61 33.98 35.17 37.17 10 37.73 37.90 35.67 35.72 35.98 36.20 36.58 37.38 36.41 34.00 35.21 37.22 11 37.75 37.90 35.66 35.72 35.99 36.21 36.61 37.40 36.34 34.01 35.25 37.15 12 37.78 37.85 35.66 35.73 35.99 36.23 36.63 37.42 36.23 34.06 35.29 37.31 13 37.80 37.76 35.65 35.72 35.99 36.24 36.65 37.44 36.13 34.10 35.30 37.37 14 37.81 37.63 35.64 35.73 36.00 36.25 36.67 37.46 36.08 34.14 35.34 37.37 15 37.83 37.56 35.64 35.73 35.98 36.27 36.68 37.48 35.70 34.17 35.37 37.40 16 37.86 37.52 35.63 35.74 35.97 36.28 36.69 37.52 35.95 34.21 35.40 37.46 17 37.88 37.48 35.62 35.75 35.96 36.28 36.71 37.54 35.95 34.25 35.44 37.49 18 37.90 37.48 35.62 35.77 35.96 36.28 36.73 37.57 35.93 34.27 35.47 37.53 19 37.92 36.95 35.62 35.79 35.98 36.28 36.77 37.59 35.91 34.33 35.52 37.61 20 37.95 36.73 35.62 35.81 35.98 36.28 36.79 37.59 35.79 34.39 35.54 37.66 21 37.97 36.55 35.62 35.81 35.99 36.28 36.79 37.59 34.90 34.41 35.73 37.65 22 38.01 36.45 35.62 35.81 35.99 36.28 36.85 37.57 34.85 34.41 35.89 37.70 23 38.04 36.38 35.62 35.83 36.01 36.31 36.90 37.57 35.05 34.45 36.00 37.78 24 38.06 36.33 35.63 35.86 36.01 36.34 36.94 37.55 34.40 34.51 36.14 37.83 25 38.06 36.29 35.63 35.87 36.02 36.35 36.98 37.55 34.13 34.55 36.23 37.85 26 38.06 36.26 35.63 35.89 36.04 36.35 37.02 37.55 33.94 34.59 36.30 37.89 27 38.07 36.24 35.63 35.92 36.05 36.36 37.05 37.53 33.80 34.63 36.38 37.93 28 38.07 36.22 35.63 35.94 36.07 36.39 37.09 37.49 33.74 34.66 36.46 37.96 29 38.07 36.21 35.63 35.95 36.40 37.12 37.45 33.69 34.70 36.54 37.99 30 38.07 36.19 35.63 35.97 36.41 37.16 37.35 33.63 34.75 36.62 38.01 31 38.07 35.63 35.97 36.43 37.30 34.80 36.67 LOW 38.07 38.09 36.19 35.97 36.07 36.43 37.16 37.59 37.27 34.80 36.67 38.01 HIGH 37.54 36.19 35.62 35.65 35.94 36.10 36.44 37.19 33.68 33.67 34.82 36.74 WTR YR 1987 MEAN 36.3 LOW 38.09 HIGH 33.67 26 30 34 38 42 ONDJ FMAMJJ ASONDJ FMAMJJ ASONDJ FMAMJ J AS 1984 1985 1986 1987 340 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174525064460600. Local number, 7. LOCATION.--Lat 17°4525", long 64°4606. Owner: Virgin Islands Government. Name: Concordia 14. AQUIFER.--Sand and gravel. WELL CHARACTERISTICS.--Drilled production water-table well, diameter 6 in (0.15 m). cased 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 point: Top of 0.50 in (0.01 m) pipe on top of pump concrete base, 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, 12.54 ft (3.82 m) below land-surface datum, June 17, 1987; lowest water level measured, 41.75 ft (12.73 m) below land-surface datum, Feb. 24, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 20 21.46 Apr. 27 28.72 June 17 12.54 174527064460100. Local number, 8. LOCATION.--Lat 17°45'27", long 64°46'01. Owner: Virgin Islands Government. Name: 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 point: Top of 6 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, 16.68 ft (5.08 m) below land-surface datum, Nov. 13, 1984; lowest water level measured, a28.39 ft (a8.66 m) below land-surface datum, Dec. 8, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 20 23.86 Apr. 27 25.57 June 17 24.81 a Pumping. 341 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174532064460300. Local number, 9. LOCATION.--Lat 17°4532", long 64°4603. Owner: Virgin Islands Government. Name: 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 point: 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 20 a32.13 Apr. 27 12.24 June 17 a13.58 174329064454700. Local number, 10. LOCATION.--Lat 17°43'29", long 64°4547". Owner: Virgin Islands Government. Name: Barren Spot 5 (PWD-5). AQUIFER.--Alluvium and marl. WELL 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 point: 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, a75.52 ft (a23.02 m) below land-surface datum, Sept. 8, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 20 65.57 Apr. 27 a70.36 June 17 a70.21 a Pumping. 342 GROUND-WATER LEVELS ST. THOMAS, U.S. VIRGIN ISLANDS 182050064580400. Local number, 1. LOCATION.--Lat 18°2050", long 64°5804. Owner: U.S. Government, Virgin Islands Government. Name: USGS-8 (Family well - Thatch Farm). 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 point: 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. 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, a57.94 ft (17.66 m) below land-surface datum, Jan. 21, 1987. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 21 a57.94 Apr. 28 56.87 June 17 14.30 182138064543100. Local number, 2. LOCATION.--Lat 18°2138", long 64°54'31'. Owner: Mahogany Run Resort. Name: 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 120 ft (36.6 m) above mean sea level, from topographic map. Measuring point: Top of 6 in (0.15 m) casing, 1.20 ft (0.36 m) below land-surface datum. REMARKS.--Observation well. Water levels affected by nearby pumping well. 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. 88.62 ft (27.01 m) below land-surface datum, Oct. 4. 1984. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 21 35.66 Apr. 30 43.94 June 18 13.85 182138064542500. Local number, 3. LOCATION.--Lat 18°21'38", long 64°54'25". Owner: Mahogany Run Resort. Name: 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-surface datum is 130 ft (39.6 m) above mean sea level, from topographic map. 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, 17.52 ft (5.34 m) below land-surface datum, July 1, 1986; lowest water level measured, a103.85 ft (31.65 m) below land-surface datum, Oct. 4, 1984. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 21 a67.40 Apr. 30 a63.74 June 18 19.17 a Pumping. 343 GROUND-WATER LEVELS ST. THOMAS. U.S. VIRGIN ISLANDS 182136064541900. Local number, 4. LOCATION.--Lat 18°2136, long 64°5419". Owner: Mahogany Run Resort Name: 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 140 ft (42.7 m) above mean sea level, from topographic map. Measuring point: 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 21 39.32 Apr. 30 41.49 June 18 20.02 182029064535200. Local number, 5. LOCATION.--Lat 18°2029, long 64°5352". Owner: Virgin Islands Government, V.I. Housing Authority. Name: 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 point: Top of 6 in (0.15 m) casing, 2.30 ft (0.70 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 54.24 ft (16.53 m) below land-surface datum. Nov. 20, 1984; 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 21 39.32 Apr. 30 85.37 June 18 66.95 a Pumping. 344 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. Name: 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 ft (21.3 m). 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, 3.72 ft (1.13 m) below land-surface datum, May 22, 1986; 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 21.34 20.43 18.85 22.59 23.06 24.44 24.02 25.51 15.62 18.89 22.68 24.40 2 21.43 20.42 19.26 22.74 23.13 24.42 24.11 25.53 15.39 18.97 22.73 24.38 3 21.52 20.43 19.62 22.83 23.20 24.41 24.19 25.54 15.42 19.11 22.79 24.24 4 21.59 20.39 19.94 22.93 23.25 24.41 24.27 25.52 15.17 19.27 22.87 24.10 5 21.64 20.35 20.24 23.01 23.29 24.42 24.36 25.52 14.75 19.40 22.94 24.03 6 21.70 20.29 20.57 23.09 23.33 24.47 24.42 25.31 14.61 19.57 22.96 24.03 7 21.76 20.11 20.86 23.15 23.38 24.52 24.46 22.74 14.71 19.79 22.98 24.09 8 21.84 19.90 21.14 23.06 23.41 24.59 24.48 21.83 14.97 19.97 23.04 24.14 9 21.93 19.62 21.38 23.01 23.45 24.63 24.47 21.33 15.29 20.15 23.06 24.16 10 21.99 19.44 21.57 22.99 23.50 24.67 24.48 21.10 15.69 20.31 23.06 24.22 11 22.05 19.34 21.66 22.91 23.63 24.73 24.50 21.01 16.10 20.56 23.06 24.36 12 22.13 19.29 21.69 22.82 23.78 24.80 24.51 20.94 16.55 20.81 23.09 24.49 13 22.20 19.30 21.70 22.74 23.93 24.86 24.49 20.55 17.01 20.98 23.21 24.63 14 22.28 19.36 21.71 22.68 24.08 24.97 24.44 20.41 17.43 21.15 23.32 24.72 15 22.34 19.41 21.63 22.69 24.17 25.04 24.32 20.47 17.88 21.29 23.36 24.79 16 22.39 19.40 21.45 22.63 24.21 24.83 24.25 20.62 18.26 21.39 23.33 24.84 17 22.46 18.58 21.32 22.54 24.21 24.54 24.34 20.82 18.66 21.50 23.32 24.90 18 22.49 17.72 21.24 22.48 24.23 24.04 24.37 21.00 19.03 21.61 23.35 24.99 19 22.51 17.24 21.21 22.41 24.26 23.72 24.47 21.21 19.38 21.72 23.35 25.07 20 22.52 17.09 21.20 22.33 24.29 23.54 24.60 21.35 19.70 21.82 23.38 25.16 21 22.52 17.11 21.19 22.00 24.30 23.48 24.75 21.47 19.91 21.96 23.43 25.25 22 22.48 17.22 21.30 22.23 24.31 23.46 24.85 21.56 19.61 22.04 23.50 25.35 23 22.32 17.35 21.51 22.31 24.31 23.48 24.97 21.62 18.84 22.09 23.57 25.46 24 22.00 17.50 21.72 22.39 24.32 23.53 25.04 21.57 18.32 22.14 23.67 25.55 25 21.67 17.66 21.91 22.48 24.36 23.61 25.07 20.77 18.12 22.20 23.74 25.64 26 21.35 17.81 22.00 22.54 24.43 23.67 25.13 19.62 18.10 22.27 23.80 25.74 27 21.08 17.94 22.06 22.63 24.46 23.72 25.21 18.91 18.21 22.34 23.90 25.80 28 20.83 18.07 22.14 22.71 24.45 23.79 25.33 18.59 18.39 22.40 24.02 25.85 29 20.65 18.21 22.22 22.80 23.83 25.41 18.48 18.64 22.48 24.15 25.90 30 20.53 18.49 22.32 22.89 23.89 25.48 17.10 18.82 22.55 24.27 25.94 31 20.46 22.44 22.99 23.96 16.24 22.62 24.37 LOW 22.52 20.43 22.44 23.15 24.46 25.04 25.48 25.54 19.91 22.62 24.37 25.94 HIGH 20.46 17.09 18.85 22.00 23.06 23.46 24.02 16.24 14.61 18.89 22.68 24.03 WTR YR 1987 MEAN 22.1 LOW 25.94 HIGH 14.61 2 11 c.) 'au? 20 c:1 1 29 ONDJFMAMJJ ASONDJFMAMJJ ASONDJFMAMJ AS 1984 1985 1986 1987 345 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182010064472600. Local number, 1. LOCATION.--Lat 18°2010, long 64°4726. 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 0 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. Water 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) below 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 22 26.15 Apr. 29 33.37 June 18 20.04 182109064460300. Local number, 2. LOCATION.--Lat 18°2109". long 64°4603. Owner: U.S. Government, National Park Service. Name: 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Date level Jan. 22 a35.96 a Pumping. + Above land-surface datum. 346 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182116064451000. Local number, 3. LOCATION.--Lat 18°2116, long 64°4510". Owner: U.S. Government, National Park Service. Name: NPS-6 (Cinnamon Bay). AQUIFER.--Volcanic rocks of Cretaceous Age. WELL CHARACTERISTICS.--Drilled water-table production well, diameter 6-in (0.15 m), cased 0-51 ft (0-15.55 m), open hole 51-70 ft (15.5c-21.34 m). Depth 70 ft (21.34 m). DATUM.--Elevation of land-surface datum is about 60 ft (18.3 m) above mean sea level, from topographic map. Measuring point: Hole on 6 in (0.15 m) casing, 2.00 ft (0.61 m) above land-surface datum. Prior to June 29, 1983, top of 6 in (0.15 m) casing at land-surface datum. REMARKS.--Abandoned as production well. Recording observation well. PERIOD OF RECORD.--August 1964 to December 1969, discontinued. March 1982 to current year. 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 56.46 56.12 53.58 55.29 55.87 56.26 56.53 56.96 56.89 56.75 57.30 57.60 2 56.46 56.14 53.42 55.33 55.85 56.25 56.56 56.94 56.92 56.77 57.32 57.62 3 56.45 56.16 53.39 55.37 55.84 56.22 56.59 56.94 56.94 56.78 57.33 57.63 4 56.44 56.16 53.40 55.40 55.83 56.22 56.60 56.94 56.91 56.78 57.34 57.63 5 56.43 56.15 53.46 55.42 55.82 56.22 56.62 56.97 56.74 56.79 57.34 57.63 6 56.43 56.13 53.55 55.42 55.82 56.25 56.64 56.99 56.62 56.81 57.34 57.62 7 56.45 56.12 53.65 55.43 55.85 56.30 56.65 56.99 56.54 56.83 57.37 57.61 8 56.46 56.11 53.74 55.45 55.90 56.35 56.66 56.99 56.49 56.86 57.39 57.61 9 56.47 56.10 53.81 55.45 55.94 56.40 56.66 57.01 56.46 56.91 57.40 57.61 10 56.47 56.10 53.93 55.45 56.00 56.42 56.68 57.01 56.45 56.93 57.42 57.61 11 56.44 56.12 54.02 55.46 56.04 56.44 56.70 56.99 56.45 56.95 57.45 57.61 12 56.42 56.14 54.11 55.50 56.05 56.48 56.72 56.97 56.46 56.98 57.46 57.63 13 56.39 56.17 54.22 55.54 56.05 56.50 56.73 56.94 56.48 57.00 57.47 57.64 14 56.39 56.19 54.33 55.57 56.01 56.50 56.76 56.94 56.52 57.03 57.48 57.66 15 56.36 56.20 54.41 55.59 55.99 56.46 56.76 56.95 56.56 57.05 57.50 57.70 16 56.35 56.21 54.51 55.60 55.97 56.43 56.79 56.98 56.59 57.06 57.48 57.71 17 56.31 56.19 54.58 55.60 55.97 56.38 56.81 57.00 56.63 57.07 57.44 57.70 18 56.31 56.04 54.63 55.60 55.98 56.31 56.80 57.01 56.65 57.09 57.42 57.68 19 56.29 55.82 54.69 55.63 56.05 56.28 56.79 57.03 56.69 57.11 57.40 57.65 20 56.31 55.68 54.76 55.66 56.09 56.26 56.80 57.04 56.72 57.12 57.40 57.63 21 56.31 55.56 54.83 55.70 56.13 56.26 56.81 57.03 56.75 57.14 57.41 57.63 22 56.29 55.48 54.87 55.73 56.18 56.27 56.83 57.00 56.75 57.15 57.46 57.63 23 56.25 55.39 54.89 55.77 56.22 56.30 56.85 56.96 56.72 57.16 57.51 57.65 24 56.19 55.32 54.91 55.80 56.25 56.34 56.87 56.93 56.71 57.17 57.53 57.69 25 56.15 55.27 54.92 55.83 56.30 56.38 56.91 56.91 56.71 57.19 57.56 57.71 26 56.12 55.21 54.95 55.85 56.31 56.41 56.92 56.88 56.71 57.20 57.57 57.73 27 56.11 55.06 54.98 55.87 56.30 56.41 56.93 56.85 56.72 57.21 57.57 57.74 28 56.11 54.73 55.05 55.89 56.29 56.42 56.95 56.84 56.73 57.23 57.59 57.75 29 56.11 54.25 55.12 55.91 56.43 56.96 56.84 56.74 57.25 57.59 57.76 30 56.11 53.85 55.19 55.91 56.45 56.97 56.86 56.74 57.27 57.59 57.78 31 56.11 55.24 55.90 56.50 56.88 57.28 57.59 LOW 56.47 56.21 55.24 55.91 56.31 56%50 56.97 57.04 56.94 57.28 57.59 57.78 HIGH 56.11 53.85 53.39 55.29 55.82 56.22 56.53 56.84 56.45 56.75 57.30 57.60 WTR YR 1987 MEAN 56.4 LOW 57.78 HIGH 53.39 44 o La- n WI- 47 lJJ-o Ldu 50 zitc J 53 56 ocz ;1.44 ▪ 59 ONDJFMAMJJ ASONDJFMAMJJ ASONDJFMAMJJ AS 1984 1985 1986 1987 347 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182042066454500. Local number, 5. LOCATION.--Lat 18°20'42", long 66°45'45". Owner: Virgin Islands Government. Name: DPW-6. (Sussanaberg) AQUIFER.--Louisenhoj Formation. WELL CHARACTERISTICS.--Drilled water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m). Sounded depth 70 ft (21.3 m). DATUM.--Elevation of land-surface datum is about 640 ft (195 m) above mean sea level, from topographic map. Measuring point: Top of 6 in (0.15 m) casing, 1.60 ft (0.49 m) above land-surface datum. Prior to June 28, 1983, top of 6 in (0.15 m) casing, 1.30 ft (0.40 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.--September 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level recorded, 1.33 ft (0.40 m) below land-surface datum, May 18, 1986; lowest water level recorded, 22.78 ft (6.94 m) below land-surface datum, Oct. 5, 1985. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 14.73 16.60 6.30 9.07 12.18 14.80 16.75 17.89 14.58 12.36 15.71 17.90 2 14.78 16.63 6.29 9.17 12.28 14.83 16.83 17.92 14.61 12.50 15.78 17.97 3 14.81 16.67 6.47 9.34 12.39 15.04 16.87 17.96 14.62 12.66 15.88 18.03 4 15.01 16.69 6.59 9.46 12.52 15.08 16.91 17.99 4.38 12.76 15.94 18.08 5 15.11 16.74 6.72 9.55 12.61 15.14 16.96 18.03 8.80 12.93 15.99 18.16 6 15.17 16.77 6.85 9.65 12.71 15.21 16.99 18.06 9.71 13.04 16.07 18.20 7 15.26 16.81 6.92 9.73 12.82 15.29 17.03 18.05 10.17 13.17 16.14 18.28 8 15.34 16.80 6.98 9.57 12.91 15.35 17.06 18.07 10.40 13.31 16.23 18.33 9 15.42 16.74 6.77 9.67 13.03 15.41 17.11 18.10 10.52 13.42 16.28 18.39 10 15.48 16.75 6.46 9.80 13.14 15.49 17.14 18.15 10.53 13.53 16.35 18.46 11 15.56 16.79 6.50 9.92 13.22 15.55 17.20 18.15 10.61 13.67 16.43 18.51 12 15.64 16.82 6.56 10.06 13.28 15.62 17.26 18.10 10.67 13.79 16.53 18.55 13 15.71 16.83 6.69 10.18 13.38 15.70 17.28 18.10 10.74 13.90 16.60 18.61 14 15.77 16.83 6.84 10.31 13.45 15.75 17.27 18.13 10.82 14.04 16.66 18.66 15 15.86 16.83 6.96 10.43 13.56 15.83 17.25 18.16 10.92 14.15 16.72 18.72 16 15.92 16.34 7.01 10.55 13.69 15.88 17.28 18.19 10.99 14.23 16.75 18.76 17 15.96 9.63 7.14 10.64 13.78 15.93 17.32 18.20 11.11 14.33 16.83 18.80 18 16.02 4.93 7.25 10.75 13.88 15.97 17.38 18.20 11.30 14.39 16.90 18.85 19 16.09 9.55 7.42 10.85 14.01 16.03 17.42 18.20 11.41 14.51 16.99 18.90 20 16.15 10.52 7.57 10.93 14.11 16.07 17.45 18.10 11.57 14.62 17.06 18.95 21 16.21 10.71 7.71 11.01 14.17 16.10 17.48 16.61 10.90 14.72 17.14 19.00 22 16.26 10.76 7.86 11.15 14.29 16.17 17.51 17.54 10.50 14.78 17.20 19.05 23 16.29 10.36 8.06 11.26 14.38 16.22 17.57 17.31 10.64 14.81 17.29 19.09 24 16.30 10.22 8.19 11.38 14.44 16.28 17.61 17.18 11.00 15.05 17.38 19.12 25 16.31 10.22 8.34 11.47 14.55 16.32 17.66 16.90 11.29 15.13 17.44 19.16 26 16.35 3.90 8.45 11.62 14.64 16.40 17.70 6.90 11.52 15.20 17.50 19.20 27 16.40 3.22 8.58 11.71 14.70 16.47 17.73 12.56 11.73 15.28 17.58 19.23 28 16.42 2.93 8.64 11.82 14.78 16.55 17.77 13.64 11.92 15.38 17.66 19.28 29 16.46 4.73 8.72 11.89 --- 16.60 17.84 14.10 12.05 15.47 17.72 19.32 30 16.50 5.65 8.75 11.99 16.66 17.86 14.38 12.21 15.56 17.78 19.35 31 16.56 --- 8.80 12.06 16.71 --- 14.53 --- 15.62 17.84 --- LOW 16.56 16.83 8.80 12.06 14.78 16.71 17.86 18.20 14.62 15.62 17.84 19.35 HIGH 14.73 2.93 6.29 9.07 12.18 14.80 16.75 6.90 4.38 12.36 15.71 17.90 WTR YR 1987 MEAN 14.2 LOW 19.35 HIGH 2.93 0 22 cap 5 a La 10 z if 15 N La w.) 20 cez W 25 4c 3 ONDJ FMAMJ 1984 1985 AS ONDJ FMAMJ 1986 J ASONDJFMAMJJ AS 1987 348 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182044064454600. Local number, 6. LOCATION.--Lat 18°20'44", long 64°4546. Owner: Virgin Islands Government. Name: 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 point: 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, a107.4 ft (32.7 m) below land-surface datum, Sept. 19, 1985. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 22 a91.29 Apr. 29 39.50 June 18 42.35 182044064454800. Local number, 7. LOCATION.--Lat 18°2044, long 64°4548. Owner: Virgin Islands Government. Name: 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 point: 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 22 a50.66 Apr. 29 29.15 June 18 31.64 182044064454900. Local number, 8. LOCATION.--Lat 18°20 1 44", long 64°45'49. Owner: Virgin Islands Government. Name: 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 640 ft (195 m) above mean sea level, from topographic mpa. 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 22 56.67 Apr. 29 26.10 June 18 27.01 a Pumping. 349 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182044064455000. Local number, 9. LOCAT1ON.--Lat 18°2044, long 64°4550". Owner: Virgin Islands Government. Name: 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 640 ft (195 m) above mean sea level, from topographic map. Measuring point: 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, 17.10 ft (5.21 m) below land-surface datum, July 2, 1986; lowest water level measured, 52.44 ft (15.99 m) below land-surface datum. May 19, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 22 50.00 Apr. 29 35.49 June 18 38.49 182044064455200. Local number, 10. LOCATION.--Lat 18°2044", long 64°4552. Owner: Virgin Islands Government. Name: 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 640 ft (195 m) above mean sea level. Measuring point: 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. PERO° OF RECORD.--September 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 16.60 ft (5.06 m) below land-surface datum, July 2, 1986; 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATIONS Water Water Water Date level Date level Date level Jan. 22 38.43 Apr. 29 33.04 June 18 36.08 350 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 181956064464500. Local number, 11. LOCATION.--Lat 18°19'56", long 64°46'45". Owner: Virgin Islands Government. Name: Guinea Gut Well. AQUIFER.--Louisenhoj Formation (Donnelly, 1959). WELL CHARACTERISTICS.--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 point: 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, 3.05 ft (0.93 m) below land-surface datum, June 13, 1986; 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 1986 TO SEPTEMBER 1987 INSTANTANEOUS OBSERVATION AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 10.66 12.70 4.54 5.43 7.96 10.82 13.39 16.02 13.30 8.25 12.12 15.94 2 10.79 12.73 4.57 5.51 8.05 10.93 13.53 16.08 13.24 8.37 12.25 16.07 3 10.93 12.79 4.63 5.61 8.16 11.07 13.65 16.17 13.03 8.47 12.37 16.19 4 11.05 12.79 4.67 5.70 8.27 11.09 13.74 16.20 8.90 8.60 12.45 16.29 5 11.19 12.86 4.75 5.75 8.35 10.93 13.84 16.27 7.51 8.72 12.48 16.40 6 11.30 12.87 4.83 5.78 8.41 11.00 13.92 16.33 7.17 8.83 12.55 16.53 7 11.42 12.90 4.82 5.76 8.51 11.07 14.01 16.32 7.05 8.95 12.60 16.66 8 11.55 12.64 4.88 5.77 8.60 11.13 14.08 16.32 7.17 9.09 12.68 16.77 9 11.67 12.51 4.77 5.91 8.72 11.21 14.17 16.35 7.39 9.27 12.79 16.86 10 11.73 12.49 4.74 6.00 8.82 11.33 14.26 16.37 7.59 9.40 12.90 16.96 11 11.81 12.54 4.72 6.06 8.91 11.44 14.38 16.38 7.81 9.52 13.02 17.06 12 11.91 12.56 4.74 6.16 8.95 11.52 14.47 16.36 .04 9.71 13.16 17.13 13 11.99 12.57 4.76 6.24 8.97 11.61 14.55 16.35 .20 9.86 13.31 17.19 14 12.10 12.58 4.80 6.36 9.03 11.73 14.60 16.37 .37 10.01 13.47 17.27 15 12.22 12.55 4.79 6.42 9.14 11.83 14.61 16.40 .48 10.14 13.57 17.37 16 12.34 10.15 4.83 6.50 9.26 11.87 14.66 16.46 .51 10.16 13.58 17.46 17 12.35 6.98 4.86 6.57 9.39 11.91 14.75 16.51 .60 10.26 13.73 17.54 18 12.35 5.93 4.90 6.69 9.51 11.92 14.83 16.55 .70 10.35 13.87 17.62 19 12.41 5.60 4.95 6.76 9.67 11.99 14.93 16.59 .77 10.48 14.03 17.72 20 12.46 5.51 4.99 6.79 9.82 12.05 15.01 16.41 .81 10.63 14.18 17.82 21 12.53 5.50 5.01 6.85 9.88 12.12 15.10 16.29 .34 10.74 14.34 17.92 22 12.56 5.46 5.07 6.93 10.04 12.20 15.21 16.15 .93 10.86 14.48 17.99 23 12.58 5.42 5.15 7.07 10.17 12.30 15.32 16.05 7.74 11.01 14.65 18.05 24 12.57 5.33 5.22 7.09 10.29 12.44 15.42 15.95 7.78 11.17 14,81 18.14 25 12.52 5.30 5.18 7.29 10.43 12.54 15.53 15.57 7.85 11.28 14.97 18.22 26 12.49 4.86 5.18 7.46 10.57 12.64 15.63 14.36 7.95 11.37 15.11 18.31 27 12.51 4.35 5.18 7.60 10.58 12.77 15.73 13,94 8.05 11.50 15.26 18.40 28 12.52 4.22 5.22 7.71 10.68 12.91 15.82 13.72 8.12 11.65 15.40 18.48 29 12.53 4.27 5.24 7.74 --- 13.02 15.90 13.56 8.17 11.79 15.56 18.56 30 12.56 4.42 5.24 7.85 13.15 15.95 13.45 8.17 11.92 15.68 18.62 31 12.64 --- 5.33 7.92 13.28 --- 13.38 --- 12.03 15.81 --- LOW 12.64 12.90 5.33 7.92 10.68 13.28 15.95 16.59 13.30 12.03 15.81 18.62 HIGH 10.66 4.22 4.54 5.43 7.96 10.82 13.39 13.38 7.05 8.25 12.12 15.94 WTR YR 1987 MEAN 11.2 LOW 18.62 HIGH 4.22 3: 0 W wo 9 Z_ 4.1 18 >v) cK z .4( 27 ONDJFMAMJ J ASONDJ FMAM JJ ASO NDJ FMAMJJ AS 1984 1985 1986 1987 351 INDEX Access to WATSTORE data Acre-foot, definition of Adenosine triphosphate, definition of Adjuntas, Lago Garzas No. 1 near dam near Adjuntas, Rio Grande de Arecibo near Aguada, Rio Culebrinas near Aguas Buenas, Rio de Bayam6n near Algae growth potential, definition of Analyses of samples collected at water-quality partial-record stations in Puerto Rico Masco, Rio Grande de Anasco near Aquifer, definition of Arecibo, Rio Grande de Arecibo above Artesian, definition of Artificial substrate, definition of Ash mass, definition of Bairoa near Caguas, Rio Bacteria, definition of Bahia de San Juan No. 5 at San Juan Bayamon, at Flood Channel at Bayam6n, Rio de near Aguas Buenas Bayamon basin, Rio de, ground-water records in water-quality records in Bayarn6n, Rio Guaynabo near Bayaney, Rio Camuy near Bed material, definition of Bed load, definition of Bed load discharge, definition of Biochemical oxygen demand, definition of Biomass, definition of Blanca at El Jagual, Quebrada Blanco basin, Rio, gaging station records in Blasina near Carolina, Quebrada Blue-green algae, definition of Bonne Resolution Gut at Bonne Resolution, St. Thomas, VI Borinquen, Rio Turabo at Bottom material, definition of Bucana basin, Rio, water-quality records in Caguas, Lago Loiza No. 4 near mouth near Caguas, Rio Bairoa near Caguas, Rio Cagiiitas at Highway 30 at Caguas, Rio Grande de Loiza at Cagiiitas at Highway 30 at Caguas, Rio Caimito near Juncos, Quebrada Campo Rico, Rio Canovanas near Camuy basin, Rio, gaging station records in ground-water records in Camuy near Bayaney, Rio near Hatillo Canal Principal de Diversiones at Lago de Guajataca Canovanas near Campo Rico, Rio Caonillas above Lago Caonillas near Jayuya, Rio Carolina, Quebrada Blasina near Catano, Rio Hondo at Rood Channel near Cayaguas at Cerro Gordo, Rio Page 31 32 32 282-291 70-71 270-271 134-135 32 279-291 263-264 32 78-79 32 42 33 165-166 32 145 138-139 134-135 315 134-139 136-137 64-65 33 41 41 33 33 152-153 200-201 148-149 39 329 158-159 33 226-227 279-281 165-166 163-164 160-162 163-164 167-168 181-182 64-67 297 64-65 66-67 56-57 181-182 74-75 148-149 132-133 156-157 Page Cayey, Lago Carite No. 1 near dam 282-291 Cayey, Lago Carite No. 3 on Rio de la Plata near 279-281 Cells/volume, definition of 33 Central Cambalache, Rio Grande de Arecibo at 90-91 Central Rufina, Rio Guayanilla at 234-235 Cerrillos near Ponce, Rio 226-227 Cerro Gordo, Rio Cayaguas at 156-157 Charco Hondo, Rio Tanama at 88-89 Chemical oxygen demand, definition of 34 Chico at Providencia, Rio 212-213 Chico basin, Rio, water-quality records in 212-213 Chlorophyll, definition of 34 Ciales, Rio Cialitos at Highway 649 at 103-104 Ciales, Rio Grande de Manati at 99-100 Ciales, Rio Grande de Manati at Highway 149 at 101-102 Cialitos at Highway 649 at Ciales, Rio 103-104 Cibuco at Vega Baja, Rio 115-117 below Corozal 112-114 Cibuco basin, gaging-station records in 112-115 ground-water records in 306-309 water-quality records in 117 Coamo basin, Rio, ground-water records in 321 water-quality records in 218-219 Coamo near Coamo, Rio 218-219 Color unit, definition of 34 Comerio, Rio de la Plata near 123-124 Contents, definition of 34 Control, definition of 34 Control structure, definition of 34 Cooperation 2 Corozal, Rio Cibuco below 112-114 Crest-stage station, definition of 34 Crest-stage partial-record stations, discharge at 275 Cubic foot per second, definition of 34 Cubic foot per second-day, definition of 34 Cubic feet per second per square mile, definition of 34 Culebrinas, at Highway 404 near Moca, Rio 268-269 near Aguada 270-271 near San Sebastian 266-267 Culebrinas basin, Rio, gaging station records in 268 ground-water records in 324-325 water-quality records in 266-271 Damsite, Lago Loiza at 177 Damsite, Rio Grande de Loiza below 178 Definition of terms 32-45 Descalabrado basin, Rio, gaging stations records in 220 Descalabrado near Los Llanos, Rio 220 Diatoms, definition of 39 Discharge at crest-stage partial-record stations 275 Discharge at partial-record stations in Puerto Rico 275 Discharge, definition of 34 Dissolved, definition of 35 Dissolved-solids concentrations 35 Diversity index, definition of 35 Drainage area, definition of 35 Drainage basin, definition of 35 Dry mass, definition of 33 352 INDEX El Verde, Quebrada Sonadora near El Verde, Quebrada Toronja at Espiritu Santo basin, Rio, gaging station records in water-quality records in Espiritu Santo near Rio Grande, Rio Explanation of records Fajardo basin, Rio, gaging station records in water-quality records in Fajardo below Fajardo, Rio near Fajardo Fecal coliform bacteria, definition of Fecal streptococcal bacteria, definition of Florida, Rio Grande de Arecibo below Lago Dos Bocas near Gage-height, definition of Gaging station, definition of Grande de Masco basin, Rio, gaging station records in water-quality records in Grande de Masco near Masco, Rio near Lares near San Sebastian Grande de Arecibo at Central Cambalache, Rio above Arecibo below Lago Dos Bocas near Florida near Adjuntas near Utuado Grande de Arecibo basin, Rio, gaging station records in ground-water records in water-quality partial-record stations, analyses of samples collected in water-quality records in Grande de Loiza at Caguas, Rio at Quebrada Arenas below Trujillo Alto Grande de Loiza basin, Rio, gaging station records in ground-water records in water-quality partial-record stations, analyses of samples collected in water-quality records in Grande de Manati at Ciales, Rio at Highway 2 near Manati at Highway 149 at Ciales near Morovis Grande de Manati basin, Rio, gaging station records in ground-water records in water-quality records in Grande de Patillas near Patillas, Rio Grande de Patillas basin, Rio, gaging station records in water-quality records in Page 184-185 185-187 184-188 189-190 188-190 9-31 195 196-199 198-199 195-197 33 33 76-77 35 35 260 258-264 263-264 258-259 260-262 90-91 78-79 76-77 70-71 72-73 78-89 298 279-291 70-91 160-162 150-151 179-180 150-182 318 279-291 148-180 99-100 105-109 101-102 96-98 96-106 299-305 94-110 214-216 214 215-216 Page Graphs: Ground-water levels at selected wells in Puerto Rico and the U.S. Virgin Islands 6 Monthly-mean discharge of selected streams in Puerto Rico 4 Green algae, definition of 39 Grid showing system for numbering wells and miscellaneous sites (latitude and longitude) 18 Ground-water level, records of 28-30 Ground-water quality, records of 30-31 Ground-water records for Puerto Rico 295-325 Ground-water records for U.S. Virgin Islands 335-350 Ground-water station, definition of 35 Ground-water stations in Puerto Rico, map showing location of 15 Ground-water stations in the U.S. Virgin Islands, map showing location of 17 Guadiana near Naranjito, Rio 125-126 Guajataca above Lago de Guajataca, Rio 54-55 above mouth near Quebradillas 60-62 at Lares 52-53 below Lago de Guajataca 58-59 Guajataca basin, Rio, gaging station records in 54-60 ground-water records in 295-296 water-quality partial-record stations, analyses of samples collected in 279-291 water-quality records in 52-62 Guanajibo near Hormigueros, Rio 252-254 near San German 241-242 Guanajibo basin, Rio, gaging station records in 243-252 ground-water records in 323 water-quality records in 241-254 Guanica, Rio Loco at 236-237 Guayanes above mouth at Playa de Guayanes, Rio 208-209 at Yabucoa 206-207 Guayanes basin, Rio, ground-water records in 320 water-quality records in 206-209 Guayanilla at Central Rufina, Rio 234-235 near Guayanilla 233 Guayanilla basin, Rio, gaging station records in 233 water-quality records in 234-235 Guaynabo near Bayamon, Rio 136-137 Guinea Gut at Bethany, St. John, VI 331 Gurabo at Gurabo, Rio 173-174 near Gurabo 175-176 Gurabo, Quebrada Mamey near 171-172 Hardness, definition of 36 Hatillo, Rio Camuy near 66-67 Hato Rey, Rio Piedras at 142-143 Hondo at Flood Channel near Catario, Rio 132-133 Hondo basin, Rio, ground-water records in 314 water-quality records in 132-133 Hormigueros, Rio Guanajibo near 252-254 Hormigueros, Rio Rosario near 243-251 Humacao at Highway 3 at Humacao, Rio 204-205 353 INDEX Page Humacao basin, Rio, water-quality records in 204-205 Hydrologic Bench-Mark Network, definition of 36 Hydrologic conditions, summary of 2-9 Hydrologic unit, definition of 36 lcacos near Naguabo, Rio 200-201 Identification numbers, stations 12-18 !nabOn at Real Abajo, Rio 224-225 Inaban basin, Rio, gaging station records in 224-225 Instantaneous discharge, definition of 34 Introduction 1 Jacaguas at Juana Diaz, Rio 221 Jacaguas basin, Rio, gaging station records in 221 Jagual, Quebrada Blanca at El 152-153 Jayuya, Rio Caonillas above Lago Caonillas near 74-75 Jolly Hill Gut at Jolly Hill, St. Croix, VI 332 Joyuda, Quebrada Mamey at 240 Juana Diaz, Rio Jacaguas at 221 Juncos, Quebrada Caimito near 167-168 Juncos, Rio Valenciano near 169-170 Lago Carite No.1 near dam near Cayey 282-291 No. 3 on Rio de la Plata near Cayey 279-281 Lago de Guajataca, Canal Principal de Diversiones at .. 56-57 No. 1 near dam near Quebradillas 282-291 No. 3 near mouth near Quebradillas 279-281 Rio Guajataca above 54-55 Rio Guajataca below 58-59 Lago Dos Bocas No. 1 near dam near Utuado 282-291 No. 3 at west branch near Utuado 279-281 Lago Garzas No. 1 near dam near Adjuntas 282-291 Lago La Plata No. 3 near dam near Naranjito 282-291 No. 5 near mouth near Naranjito 279-281 Lago Loiza at damsite 177 No. 4 near mouth near Caguas 279-281 No. 7 near dam near Trujillo Alto 282-291 Laguna Joyuda basin, gaging station records in 240 Laguna San Jos6 No. 2 at San Juan 144 Laguna Tortuguero basin, water-quality records in 110 Laguna Tortuguero outlet near Vega Baja 110 Land-surface datum, definition of 36 La Plata at Proyecto La Plata, Rio de 120-122 at Highway 2 near Toa Alta 130 at Toa Alta 127-129 near Cometio 123-124 La Plata basin, Rio de, gaging station records in . 120-130 ground-water records in 310-313 water-quality partial-record stations, analyses of samples collected in 279-291 water-quality records in 121-129 Lares, Rio Grande de Masco near 258-259 Lares, Rio Guajataca at 52-53 Levels for Puerto Rico, ground-water 295-325 Levels for U.S. Virgin Islands, ground water 335-350 Page Loco at Guanica, Rio 236-237 Loco basin, Rio, water-quality records in 236-237 Los Llanos, Rio Descalabrado near 220 Mamey at Joyuda, Quebrada 240 Mamey near Gurabo, Quebrada 171-172 Marneyes near Sabana, Rio 191-192 Mameyes basin, Rio, gaging station records in 191-192 Manati, Rio Grande de Manati at Highway 2 near . . 105-109 Maps: Location of continuous surface-water stations and crest-stage gage stations in Puerto Rico 13 Location of ground-water stations in Puerto Rico 15 Location of ground-water stations in the U.S. Virgin Islands 17 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 the U.S. Virgin Islands 16 Location of water-quality stations in Puerto Rico 14 Rio Camuy basin 63 Rio Cibuco basin 111 Rio Culebrinas basin 265 Rio Grande de Arecibo basin 69 Rio Grande de Loiza basin 147 Rio Grande de Manati basin 93 Rio Guajataca basin 51 Rio Guanajibo basin 239 Rio Herrera to the Rio Anton Ruiz basins 183 Rio Hondo to the Rio Puerto Nuevo basins 131 Rio Humacao to the Rio Seco basins 203 Rio Inabon to the Rio Loco basins 223 Rio de la Plata basin 119 Rio Salinas to the Rio Jacaguas basins 217 Rio Yaguez and the Rio Grande de Masco basins 255 Maunabo at Maunabo, Rio 210-211 Maunabo basin, Rio, water-quality records in 210-211 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 11 Mayaguez, Rio Yagijez near 256-257 Mean concentration, definition of 41 Mean discharge, definition of 34 Measuring point, definition of 36 Metamorphic stage, definition of 36 Methylene blue active substances, definition of 36 Micrograms per gram, definition of 36 Micrograms per liter, definition of 36 Milligrams of carbon per area or volume per unit time for periphyton and macrophytes and for phytoplankton, definition of 40 Milligrams of oxygen per area or volume per unit time for periphyton and macrophytes and for phytoplankton, definition of 40 Milligrams per liter, definition of 36 354 INDEX Page Moca, Rio Culebrinas at Highway 404 near 268-269 Morovis, Rio Grande de Manati near 96-98 Naguabo, Rio Icacos near 200-201 Naranjito, Lago La Plata No. 3 near dam near 282-291 Naranjito, Lago La Plata No. 5 near mouth near 279-281 Naranjito, Rio Guadiana near 125-126 National Stream-Quality Accounting Network, definition of 37 National Trends Network, definition of 38 Natural substrate, definition of 42 Networks and programs, special 9 Organic mass, definition of 33 Organism, definition of 38 Organism count/area, definition of 38 Organism count/volume, definition of 38 Orocovis near Orocovis, Rio 94-95 Parameter code, definition of 38 Partial record station, definition of 38 Partial-record stations in Puerto Rico, Discharge at 275 Partial-record stations in Puerto Rico, water quality at 279-291 Particle size, definition of 38 Particle-size classification, definition of 38 Patillas, Rio Grande de Patillas near 214-216 Percent composition, definition of 39 Periphyton, definition of 39 Pesticides, definition of 39 Phytoplankton, definition of 39 Picocurie, definition of 39 Piedras, at Hato Rey, Rio 142-143 at Rio Piedras 275 near Rio Piedras 140-141 Plankton, definition of 39 Playa de Guayanes, Rio Guayanes above mouth at .. 208-209 PoL.;h1orinated biphenyls, definition of 40 Ponce, Rio Cerrillos near 226-227 Ponce, Rio Portugues at 231-232 Ponce, Rio Portugues near 228-230 at Ponce 231-232 near Ponce 228-230 Portugues basin, Rio, gaging station records in 228 water-quality records in 228-230 Primary productivity, definition of 40 Programs, special networks and 9 Providencia, Rio Chico at 212-213 Proyecto La Plata, Rio de La Plata at 120-122 Publications on techniques of water-resources investigations 47-48 Puerto Nuevo basin, Rio, crest-stage partial-record station in 275 ground-water records in 315-317 water-quality records in 140-145 Page Quality of water records of Puerto Rico, surface- and 51-271 Quebrada Arenas, Rio Grande de Loiza at 150-151 Quebradillas, Lago Guajataca No. 1 near dam near 282-291 Ouebradillas, Lago Guajataca No. 3 near mouth near 279-281 Ouebradillas, Rio Guajataca above mouth near 60-62 Radiochemical program, definition of 40 Real Abajo, Rio Inabon at 224-225 Records, explanation of 9-31 Records of ground-water levels 28-30 Records of ground-water quality 30-31 Records of stage and water discharge 18-23 Records of surface-water quality 23-28 Recoverable from bottom material, definition of 40 Return period, definition of 40 Rio Grande, Rio Espiritu Santo near 188-190 Rio Piedras, Rio Piedras near 140-141 Rosario near Hormigueros, Rio 243-251 Runoff, in inches, definition of 40 Sabana at Sabana, Rio 193-194 Sabana basin, Rio, gaging station records in 193-194 Sabana, Rio Mameyes near 191-192 Salvatierra near San Lorenzo, Quebrada 154-155 San German, Rio Guanajibo near 241-242 San Juan, Bahia de San Juan no. 5 at 145 San Juan, Laguna San Jose No. 2 at 144 San Lorenzo, Quebrada Salvatierra near 154-155 San Sebastian, Rio Culebrinas near 266-267 San Sebastian, Rio Grande de /Masco near 260-262 Seco basin, Rio, ground-water records in 319 Sediment, definition of 41 Sodium-adsorption-ratio, definition of 42 Sonadora near El Verde, Quebrada 184-185 Solute, definition of 42 Special network and programs 9 Specific conductance, definition of 42 Stage-discharge relation, definition of 42 Station identification numbers 12-18 St. Croix, VI, Jolly Hill Gut at Jolly Hill 332 St. John, VI, Guinea Gut at Bethany 331 Streamflow, definition of 42 St. Thomas, VI, Bonne Resolution Gut at Bonne Resolution 329 St. Thomas, VI, Turpentine Run at Mariendal 330 Substrate, definition of 42 Summary of hydrologic conditions 2-9 Surface and quality-of-water records for Puerto Rico .. 51-271 Surface area, definition of 42 Surface-water quality, records of 23-28 Surface-water records for U.S. Virgin Islands 329-332 Surface-water and crest-stage gage stations in Puerto Rico, map showing location of 13 Surface-water stations in U.S. Virgin Islands, map showing location of 16 355 INDEX Surficial bed material, definition of Suspended, definition of Suspended-recoverable, definition of Suspended sediment, definition of Suspended-sediment concentration, definition of Suspended-sediment discharge, definition of Suspended-sediment load, definition of Suspended-total, definition of Tanama at Charco Hondo, Rio near Utuado Taxonomy, definition of Techniques of water-resources investigations, publications on Terms, definition of Thermograph, definition of Time-weighted average, definition of Toa Alta, Rio de La Plata at Toa Alta, Rio de La Plata at Highway 2 near Tons per acre-foot, definition of Tons per day, definition of Toronja at El Verde, Quebrada Total, definition of Total coliform bacteria, definition of Total discharge, definition of Total organism count, definition of Total-recoverable, definition of Total sediment discharge, definition of Total-sediment load, definition of Tritium network, definition of Trujillo Alto, Lago Loiza No. 7 near dam near Trujillo Alto, Rio Grande de Loiza below Turabo at Borinquen, Rio Turpentine Run at Mariendal, St. Thomas, VI Utuado, Lago Dos Bocas No. 1 near dam near Utuado, Lago Dos Bocas No. 3 at west branch near Utuado, Rio Grande de Arecibo near Utuado, Rio Tanarna near Valenciano near Juncos, Rio Vega Baja, Laguna Tortuguero outlet near Vega Baja, Rio Cibuco at Water-discharge, records of stage and Water-quality partial-record stations in Puerto Rico, analyses of samples collected at Water-quality stations in Puerto Rico, map showing location of Water-resources investigations, publications on techniques of Water year, definition of WATSTORE data, Access to WDR, definition of Weighted average, definition of Page 42 42 43 41 41 41 41 43 88-89 80-87 43 46-47 32-45 43 43 127-129 130 44 44 186-187 44 32 44 38 44 41 41 44 282-291 179-180 158-159 330 282-291 279-281 72-73 80-87 169-170 110 115-117 18-23 279-291 14 46-47 44 31 44 45 Page Wells - Puerto Rico: Bayam6n basin, Rio de Well 219 - Fort Buchanan No. 1 315 Cibuco basin, Rio Well 70 - Sabana Hoyos 306 Well 211 - Rosario No. 2 307 Well 212- Ponderosa TW-1 308 Well 213 - Pampano No. 2 309 Camuy basin, Rio Well 203 - Vicente Amador 297 Coamo basin, Rio Well 87 - Alomar 1 321 Culebrinas basin, Rio Well 83 - San Sebastian 324 Well 200 - Aguadilla Cement north 325 Grande de Arecibo basin, Rio Well 204 - Gilberto Rivera 298 Grande de Loiza basin, Rio Well 222 - Campo Rico 1W-1 318 Grande de Manatf basin, Rio Well 135 - Lederle 299 Well 205 - NC-05 Barceloneta near Cruce Davila 300 Well 206 - Plazuela No. 2 301 Well 207 - Cantito La Luisa 302 Well 208 - Acr6polis - Manatf 303 Well 209 - Coto Norte No. 3 304 Well 210 - Gelo Martinez 305 Guajataca basin, Rio Well 165 - Mateo Perez, Bo Salto 295 Well 202 - Carmelo Barreto-Garcia 296 Guanajibo basin, Rio Well 143 - Vivoni, Hacienda Arnistad 323 Guayanes basin, Rio Well 96 - USGS TW-2 or Yabucoa 7 320 Hondo basin, Rio Well 218 - Levittown No 7 314 La Plata basin, Rio de Well 214- Dorado Beach No 7 310 Well 215- Maguayo No. 5 311 Well 216 - Pozo Navy - Campanillas 312 Well 217- Monserrate TVV-2 313 Puerto Nuevo basin, Rio Well 220- Parque San Luis Rey 316 Well 221 - Hyde Park 1W-10 317 Seco basin, Rio Well 6 - Juana 5 319 Wells - U.S. Virgin Islands: St. Croix Well 1 - Fairplains 6 (FP6) 335 Well 2 - USGS-10, Fairplains 2 (FP2) 336 Well 3 - Golden Grove 6 (PW6) 337 Well 4 - Golden Grove 1 (PW1) 338 Well 6- Adventure 28 339 Well 7- Concordia 14 340 Well 8 - Concordia 1 (main pump house) 340 Well 9 - Concordia 7 341 Well 10 - Barren Spot 5 (PWD-5) 341 356 INDEX St. John Well 1 - NPS-2 (Cruz Bay) Well 2 - NPS-5 (Trunk Bay) Well 3 - NPS-6 (Cinnamon Bay) Well 5 - DPW-6 Well 6 - DPW-5 Well 7 - DPW-4 Well 8 - DPW-3 Well 9 - DPW-2 Well 10- DPW-1 Well 11 - Guinea Gut Well St. Thomas Well 1 - USGS-8 (Family well-Thatch Farm) Well 2- Mahogany 15 Well 3- Mahogany 16 Page 345 345 346 347 348 348 348 349 349 350 342 342 342 Page Well 4 - Mahogany 17 343 Well 5 - Donoe 3 343 Well 6 - Grade School 3 344 Yauco basin, Rfo Well 132 - Yauco 2 322 Wet mass, definition of 33 WSP, definition of 45 Yabucoa, Rio Guayanes at 206-207 Yagiiez near Mayaguez, Rfo 256-257 Yagiiez basin, Rio, water-quality records in 256-257 Yauco basin, Rio, ground-water records in 322 Zooplankton, definition of 39 *U.S. GOVERNMENT PRINTING OFFICE: 1989-635-190 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 By To obtain SI units Length inches (in) 2.54x101 millimeters (mm) 2.54x10-2 meters (m) feet (ft) 3.048x10-1 meters (m) miles (mi) 1.609x10° kilometers (km) Area acres 4.047x103 square meters (m2 ) 4.047x10-' square hectometers (hm2 ) 4.047x103 square kilometers (km2 ) square miles (mi2 ) 2.590x10° square kilometers (km2 ) Volume gallons (gal) 3.785x10° liters (L) 3.785x10° cubic decimeters (dm3 ) 3.785x10-3 cubic meters (m3 ) million gallons 3.785x103 cubic meters (m3 ) 3.785x10-3 cubic hectometers (hm3 ) cubic feet (ft3 ) 2.832x10' cubic' decimeters (dm3 ) 2.832x10-2 cubic meters (m3 ) cfs-days 2.447x103 cubic meters (m3 ) 2.447x1CO cubic hectometers (hm3 ) acre-feet (acre-ft) 1.233x103 cubic meters (m3 ) 1.233x10r3 cubic hectometers (hm3 ) 1.233x10-6 cubic kilometers (km3 ) Flow cubic feet per second (ft3 /s) 2.832x101 liters per second (L/s) 2.832x10' cubic decimeters per second (dm3 /s) 2.832x10-2 cubic meters per second (m3 /s) gallons per minute (gal/min) 6.309x10-2 liters per second (Lis) 6.309x10-2 cubic decimeters per second (dm3 /s) 6.309x10-5 cubic meters per second (m3 /s) million gallons per day 4.381x101 cubic decimeters per second (dm3 /s) 4.381x10-2 cubic meters per second (m3 /s) Mass tons (short) 9.072x10-1 megagrams (Mg) or metric tons NOLS INT IE3PAI"tv U.S. DEPARTMENT OF THE INTERIOR Geological Survey GPO Box 4424 San Juan, PR 00936 U.S.MAILT OFFICIAL BUSINESS PENALTY FOR PRIVATE USE $300 SPECIAL 4TH CLASS BOOK RATE