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Water Resources Data Puerto Rico and the U.S. Virgin Islands Water Year 1983 St. Thomas Culebii 2PR CZIC*11 St. John Vieques. PR C= ° VIRGIN ISLANDS St. Crola U.S. GEOLOGICAL SURVEY WATER DATA REPORT PR-83-1 Prepared in cooperation with the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands, and other agencies CALENDAR FOR WATER YEAR 1983 1982 OCTOBER NOVEMBER DECEMBER SMTWTF S SMTW T F S SMTWTFS 1 2 1 2 3 4 5 6 1 2 3 4 3 4 5 6 7 8 9 7 8 9 10 11 12 13 5 6 7 8 9 10 11 10 11 12 13 14 15 16 14 15 16 17 18 19 20 12 13 14 15 16 17 18 17 18 19 20 21 22 23 21 22 23 24 25 26 27 19 20 21 22 23 24 25 24 25 26 27 28 29 30 28 29 30 26 27 28 29 30 31 31 1983 JANUARY FEBRUARY MARCH SMTWTF S SMTWTF S SMT W T F S 1 1 2 3 4 5 1 2 3 4 5 2 3 4 5 6 7 8 6 7 8 9 10 11 12 6 7 8 9 10 11 12 9 10 11 12 13 14 15 13 14 15 16 17 18 19 13 14 15 16 17 18 19 16 17 18 19 20 21 22 20 21 22 23 24 25 26 20 21 22 23 24 25 26 23 24 25 26 27 28 29 27 28 27 28 29 30 31 30 31 APRIL MAY JUNE SMTWTFS SMTWTF S SMTWTF S 1 2 1 2 3 4 5 6 7 1 2 3 4 3 4 5 6 7 8 9 8 9 10 11 12 13 14 5 6 7 8 9 10 11 10 11 12 13 14 15 16 15 16 17 18 19 20 21 12 13 14 15 16 17 18 17 18 19 20 21 22 23 22 23 24 25 26 27 28 19 20 21 22 23 24 25 24 25 26 27 28 29 30 29 30 31 26 27 28 29 30 JULY AUGUST SEPTEMBER SMTWTFS SMTW T F S SMTWTFS 1 2 1 2 3 4 5 6 1 2 3 3 4 5 6 7 8 9 7 8 9 10 11 12 13 4 5 6 7 8 9 10 10 11 12 13 14 15 16 14 15 16 17 18 19 20 11 12 13 14 15 16 17 17 18 19 20 21 22 23 21 22 23 24 25 26 27 18 19 20 21 22 23 24 24 25 26 27 28 29 30 28 29 30 31 25 26 27 28 29 30 31 Water Resources Data Puerto Rico and the U.S. Virgin Islands Water Year 1983 by Russell E. Curtis, Senen Guzman-Rios, and Pedro L. Diaz Culebra R St. Thomas C:ZZ (*I St. John Vieques, PR VIRGIN ISLANDS St. Cr. U.S. GEOLOGICAL SURVEY WATER DATA REPORT PR-83-1 Prepared in cooperation with the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands, and other agencies II UNITED STATES DEPARTMENT OF THE INTERIOR WILLIAM P. CLARK, Secretary GEOLOGICAL SURVEY Dallas L. Peck, Director For additional information write to: Chief, Caribbean District, WRD U.S. Geological Survey GPO Box 4424 San Juan, PR 00936 (Telephone: (809) 753-4414) 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, and the Trust Territories. These records of streamflow, ground-water levels, and quality of water provide the hydrologic information needed by state, local and Federal agencies, and the private sector for developing and managing our Nation's land and water resources. The report is the culmination of a concerted effort by dedicated personnel of the U.S. Geological Survey, Water Resources Division who collected, compiled, analyzed, verified, and organized the data, and who typed, edited, and assem­ bled the report. In addition to the authors, who had primary responsibility for assuring that the information contained herein is accurate, complete and adheres to Geological Survey policy and established guidelines, the following personnel contributed significantly to the collection, processing and tabula­ tions of the data: Zaida Aquino de Diaz Ralph Gonzalez George Arroyo Felipe Hernandez Eloy ColOn-Dieppa Carlos Martinez Margarita ConcepciOn Rafael Pena-Cortes Rene Garcia Luis Santiago-Rivera Jose R. Gonzalez Pedro Vazquez Carmen A. Garcia typed the text of the report. Jose Alicea-Ortiz and Gilberto Pena-Cruz prepared the illustrations. This report was prepared in cooperation with agencies of the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands, and with other federal agencies, under the general supervision of Ferdinand Quinones, District Chief, Caribbean District, San Juan, Puerto Rico. IV 50272 - 1 1 1. REPORT NO. 2. I. Recipient's Accession No. REPORT DOCUMENTATION PAGE USGS/WRD/HD-84/027 4. Title and Subtitle S. Report Date April 1984 Water Resources Data for Puerto Rico and the U.S. Virgin Islands, 1983. 6. 7. Author(s) S. Performing Organization Rept. No. Russell E. Curtis, Senen Guzmin-Rios and Pedro Diaz USGS-WDR-PR-83-1 9. Performing Organization Name and Address 10. Project/Task/Work Unit No. U.S. Geological Survey, Water Resources Division GPO Box 4424 11. Contract(C) or Grant(G) No. San Juan, Puerto Rico 00936 (C) (G) 12. Sponsoring Organization Name and Address 13. Type of Report & Period Covered U.S. Geological Survey, Water Resources Division Final. Oct. 1, 1982 to GPO Box 4424 Sept. 30, 1983 San Juan, Puerto Rico 00936 14. 15. Supplementary Notes Prepared in cooperation with the Commonwealth of Puerto Rico, the Territory 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 1983 water year for Puerto Rico and the U.S. Virgin Islands, consist of records of discharge, water quality of streams, and water levels of wells. This report contains discharge records for 46 gaging stations; stage only records for three lakes; water quality for 63 streamflow or lagoon sites, 13 partial-record sites, 6 miscellaneous sites, and 10 wells; and water levels for 97 observation wells. Also included are data for 131 low-flow and 1 crest-stage partial record-stations. 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 a. Descriptors *Puerto Rico, *U.S. Virgin Islands, *Surface water, *Water quality, *Ground water, Aquifers, Chemical analysis, Gaging stations, Hydrologic data, Sediments, Streamflow, Water analysis, Water levels, Water quality, Lakes. b. Identifier/Open•Ended Terms Puerto Rico, U.S. Virgin Islands, Sampling sites. c. COSATI Field/Group 18. Availability Statement No restriction on distribution. 19. Security Class (This Report) UNCLASSIFIED 21. No. of Pages 308 20. Security Class (This Page) UNCLASSIFIED 22. Price (See ANSI-Z39.18) See Instructions on Reverse OPTIONAL FORM 272 (4-77) (Formerly NTIS-351 Department of Commerce REPORT : PUBLIC WATER SUPPLIES IN PUERTO RICO, 1983, by Fernando aimez­ G6mez, Ferdinand Quinones, and Marisol Lopez - O.F. 84-126. ERRATA Please make the following change in the Conversion Table on page VI: Million gallons per year Cubic feet per second 3 (Mgal/yr) 0.00424 (ft /s) V CONTENTS Page Preface III Contents V Illustrations V Tables VI Introduction 1 Cooperation 1 Summary of hydrologic conditions 2 Definition of terms 12 Downstream order and station numbers 19 Numbering system for wells and miscellaneous sites 20 Special networks and programs 20 Explanation of stage and water-discharge records 21 Collection and computation of data 21 Accuracy of field data and computed results 24 Other data available 25 Explanation of water-quality records 25 Collection and examination of data 25 Water analysis 26 Water temperature 26 Sediment 27 Explanation of ground-water level records 27 Collection of the data 27 Surface- and quality-of-water records for Puerto Rico 29 Discharge at partial-record stations in Puerto Rico 195 Analyses of samples collected at water-quality partial-record stations in Puerto Rico 207 Ground-water records for Puerto Rico 237 Surface-water records for the U.S. Virgin Islands 267 Ground-Water records for the U.S. Virgin Islands 279 Index 297 ILLUSTRATIONS Figure 1. Graph showing comparison of average discharge for 1983 water year with median discharge for period of record for station 50038100 3 2. Graph showing comparison of average discharge for 1983 water year with median discharge for period of record for station 50071000 4 3. Graph showing comparison of average discharge for 1983 water year with median discharge for period of record for station 50112500 5 4. Graph showing comparison of average discharge for 1983 water year with median discharge for period of record for station 50144000 6 5. Map showing rainfall distribution during April 18, 1983 in the U.S. Virgin Islands 7 6. System for numbering wells and miscellaneous sites (latitude and longitude) 20 VI ILLUSTRATIONS--Continued Page Figure 7. Map showing location of continuous surface-water stations in Puerto Rico 30 8. Map showing location of water-quality stations in Puerto Rico 31 9. Map showing location of low-flow partial-record stations in Eastern Puerto Rico 32 10. Map showing location of partial-record stations in Central and Western Puerto Rico 33 11. Map showing Rio Guajataca basin 35 12. Map showing Rio Camuy basin 39 13. Map showing Rio Grande de Arecibo basin 41 14. Map showing Rio Grande de Manati basin 57 15. Map showing Rio Cibuco basin 71 16. Map showing Rio de la Plata basin 81 17. Map showing Rio Hondo to Rio Puerto Nuevo basins 89 18. Map showing Rio Grande de Loiza basin 101 19. Map showing northeastern river basins--Rio Herrera to Rio AntOn Ruiz basins 117 20. Map showing southeastern river basins--Rio Humacao to Rio Seco basins 133 21. Map showing south coast river basins--Rio Salinas to Rio Jacaguas basins 149 22. Map showing south coast river basins--Rio InabOn to Rio Loco basins 151 23. Map showing Rio Guanajibo basin 169 24. Map showing Rio Yagilez and Rio Grande de Afiasco basins 177 25. Map showing Rio Culebrinas basin 189 26. Map showing location of ground-water stations 238 27. Map showing location of surface-water stations in the U.S. Virgin Islands 268 28. Map showing location of ground-water stations in the U.S. Virgin Islands 280 TABLES Table 1. Flood data for April 18, 1983 in St. Thomas and St. John, U.S. Virgin Islands 8 2. Concentrations of dissolved inorganics of NASQAN 10 3. Factors for conversion of chemical constituents in milligrams or micrograms per liter to milliequivalents per liter 15 4. Degrees Celsius (°C) to degrees Fahrenheit (°F) 26 1 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 INTRODUCTION Water resources data for the 1983 water year for Puerto Rico and the U.S. Virgin Islands consists of stage, discharge, and water quality of streams; stage and water quality of lakes and lagoons; and water levels and quality of ground water. This report contains discharge records for 46 gaging stations; stage only records for three lakes; water quality for 63 streamflow or lagoon sites, 13 partial-record sites, 6 miscellaneous sites, and 10 wells; and water levels for 97 observation wells. Also included are data for 131 low-flow and 1 crest-stage partial record-stations. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and coopera­ ting local and federal agencies in Puerto Rico and the U.S. Virgin Islands. 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 streamflow, 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 and 1981-82 water years consist of one volume each and contain data for streamflow, water quality and ground water. These official Survey reports carry an identification number consisting of the two-letter state abbreviation, the last two digits of the water year, and the volume number. For example, this report is identified as "U.S. Geological Survey Water-Data Report PR-83-1." Water Data reports are for sale by the National Technical Information Service, U.S. Department of Commerce, Springfield, Virginia, 22161. COOPERATION The U.S. Geological Survey has had cooperative agreements with organizations 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 2 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 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 Institute, University of Puerto Rico Water Resources 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. Evironmental Protection Agency. SUMMARY OF HYDROLOGIC CONDITIONS Streamflow Streamflow in Puerto Rico during the 1983 water year was generally normal in the north and east but below normal to deficient in the south and west (figs. 1 to 4). The water year began with streamflows deficient in most parts of the Island. For many areas, this was the dryest October in the last 20 years. The rivers and streams gradually returned to normal during the winter months but by late February and early March, dry conditions returned and streamflow again became deficient. The rainy season began in mid-April, resulting in the wettest month of the year with island-wide monthly average of over eight inches, almost twice the normal. Streamflow increased to above normal over the entire Island and remained high in most areas throughout the summer. No flooding of consequence occured during the year. By late summer, unusually dry weather conditions prevailed throughout Puerto Rico and by September 1983, streamflow again became deficient island-wide. Many areas experienced the dryest September in the last 20 years. Streamflow conditions in the Virgin Islands usually follow the same general pattern as Puerto Rico. The 1983 water year was no exception except for the intense rains of April 1983. On April 18th, a low-pressure trough stalled over St. Thomas and St. John and produced one of the most intense rainfall events ever recorded in this area (fig. 5). Continuous-recording rain gages operated by National Oceanic Atmospheric Administration-National Weather Service recorded intensities of up to 2.5 inches in 1 hour and a total of 16.5 inches in 19 hours. Almost instantaneous runoff caused widespread flooding near the coastlines of St. Thomas and St. John. Parts of Charlotte Amalie in St. Thomas were inundated with four feet or more of flood water and mud. Harry S. Truman Airport was flooded for two days with two to three feet of ponded water. 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NOV. DEC. JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT. Figure 1.--Comparison of monthly-mean discharges for the 1983 water year with long-term medians at Rio Grande de Manati at Highway 2 near Manati, Puerto Rico (50038100). 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NOV. DEC. JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT. MONTHLY Figure 2.--Comparison of monthly-mean discharges for the 1983 water year with long-term medians at Rio Fajardo near Fajardo, Puerto Rico (50071000). 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NOV. DEC. JAN. FES. MAR. APR. MAY JUNE JULY AUG. SEPT. Figure 3.--Comparison of monthly-mean discharges for the 1983 water year with long-term medians at Rio Inabon at Real Abajo, Puerto Rico (50112500). 6 MONTHLY MEANDISCHARGE. INCUBIC 2000 IIIIIIIIMOUNIMUNUOINUIOUINUMIIIIIIIIIIIIINUmmumumummlinummonmsomummommommININIMIN 11111111111111111111111111111111111111111111M1111111111111M11111111111111111110111111111111111111111111111111M111111111111 11111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 1111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 IMMEMMIMMIMM1111111111111111111MUMMUMMOMMMEMENIMMEIMIMIIIMMELOMMin IMMEMEMEHOMMEMIHNIIMMOMMEMMEIMIMEMMEENEMMEMEMEMMEMOOMM 11111111111111111111111111111iiiiiiiMMIMMOMMIIIIIIIIIIIIIIM111111.1111101111111111111111111111111111111111 111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 11 1111111111111111111111111111111111111111111111M11111111111111111111111111111111111111111111111111111111111111111111111 0 1000 W 900 c 800 a. 700 1-w 600 mommaiommismimmommemommemommEmmommommomummommommEmmommommommommommommimmummommemminummommommeim mom MM e MM mommommommommummummommommmommommommommumwr-vre-mmirrorel-wirrornrrnr7mrrlr:nr.rmimmommumumm 11. 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NOV. DEC. JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT. Figure 4.--Comparison of monthly-mean discharges for the 1983 water year with long-term medians at Rio Grande de giasco near San Sebastian, Puerto Rico (50144000). 7 65605' 65°00' 55' 64°50' 18`24' 188 20' 64°50' 45' 64°40' 64°50' 45' 40' 64°35' ST. CROIX 17°45' 0 1 2 3 4 MILES 1 I I I 17°40' (Data from NOAA (NWS)5 EXPLANATION 6 6 LINE OF EQUAL RAINFALL - Contour interval 1 Inch. .4.34 NOAA WEATHER STATION - Number means precipitation In inches. £(3450) USGS GAGING STATION AND STATION NUMBER Figure 5.--Rainfall distribution during April 18, 1983 in the U.S. Virgin Islands. TABLE 1.--Peak discharges at gaging stations in St. Thomas and St. John, U.S. Virgin Islands. co Maximum previously Maximum discharge known discharge for April 18, 1983 Drainage Period Unit Fre- Station Station ar2a of Dischirge Unit dis- Discarge dis- quency number name (mi ) record Date (ft /s) charge Time (ft /s) charge (years) St. Thomas 50252000 Bonne Resolution 1963-64, Gut at Bonne 0.49 1979-83 9-4-79 218 445 1315 1,650 3,370 100+ Resolution 50276000 Turpentine Run 1963-69 at Mariendal 2.97 1979-83 9-4-79 2,500 840 - 9,700 3,270 100+ St. John 50295000 Guinea Gut at 1963-66, Bethany 0.37 1982-83 11-4-65 111 300 - 946 2,560 100+ 9 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Damages on St. Thomas and St. John were estimated by the Federal Emergency Management Administration at 12-13 million dollars and both islands were declared eligible for Federal Disaster Aid. In contrast, rainfall on St. Croix was not unusually heavy and almost no runoff occurred. The flood peaks at the two gaging stations on St. Thomas and the gage on St. John were much higher than any previously recorded peak, (table 1). The gage on Bonne Resolution Gut in St. Thomas was the only one of the three that was not damaged by the floods. The frequency of the April 18 floods in St. Thomas was estimated from unit discharges and flood-frequency data for stations in Puerto Rico. The estimates indicate that the flood frequency exceeded significantly the 100-year recurrence interval (1 percent probability of occurring in any year). Ground Water By the end of the 1982 water year the ground-water levels in Puerto Rico increased in response to the above average rainfall on September 12-13, 1982. In some areas a maximum rise of six feet was recorded. During the months of October and November 1982 the ground-water levels declined. This trend was reversed in response to above average precipitation during late November and December. From January through March, ground-water levels declined in response to below-average rainfall and increased ground-water withdrawals for public water supply, industries and irrigation. In April, a near-stationary trough produced above normal rainfall, causing a general increase in ground-water levels with a maximum rise of six feet in the south coast alluvial aquifers. Precipitation for May and June was generally normal maintaining the ground­ water levels on an increasing trend. After this period, the ground-water levels along the north coast limestone aquifers remained practically unchanged while the south coast alluvium aquifers showed some fluctuations probably in response to irrigation demands. Elsewhere in the island the declining trend was predominant. Above normal precipitation during late August reversed this trend islandwide. The rainfall for the last two months of the 1983 water year varied from below average to normal causing a decline during September. Ground-water levels in the U.S. Virgin Islands followed a pattern similar to to Puerto Rico. During April the ground-water levels increased significantly due to the intense rainfall of April 18. Ground-water levels at some wells in St. Thomas increased almost 20 feetin response to recharge from the April floods. The other two Virgin Islands, St. John and St. Croix, reflected lesser ground-water level increases. Water-Quality The results of the surface-water sampling program during water year 1983 indicate high concentrations of fecal coliform and fecal streptoccocal bacte­ rias and some contamination with trace organic compounds in the streams. In general, the water quality of the streams in Puerto Rico was essentially the same as the previous two years. 10 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Monitoring stations located close to urban zones, industrial parks and suburban zones not served by sewerage system showed the highest concentrations in bacteria population. Fecal coliform bacteria, a microorganism present in the intestines of warm-blooded animals, and which is often used as indication of the sanitary quality of the water, was found in concentrations in the thousands of colonies per hundred milliliters of sample in many streams. At some sites, concentrations were as high as millions of colonies per hundred milliliter of sample. Examples of this are: Quebrada Blasina near Carolina (station number 50050300); Rio Chico at Central Providencia (sta. 50091800), Rio Guayanilla at Central Rufina (sta. 50124700) and Rio Bairoa near Caguas (sta. 50055400). Septic tanks, cesspools, leaks in sewage systems, run-off from beef cattle feedlots, and percolation from waste ponds appear to be the main source of bacterias in streams throughout Puerto Rico. A considerable increase in the concentration of some inorganics serves as one of the important indexes of the pollution of a body of water. The inorganics which are normally absent or nearly so in the natural environment are arsenic, cadmium, chromium, lead, mercury, selenium, and silver. These inorganics have been designated as having a detrimental effect on human health. The National Interim Primary Drinking Water Regulations (Environmental Protection Agency, 1976) fixed the maxium permissible level for those inorganics in drinking water as follows: Concentration Constituent Micrograms per Liter Arsenic 50 Cadmium 10 Chromium 50 Lead 50 Mercury 2 Selenium 10 Silver 50 Mercury is one of the most dangerous of those inorganics. This metal is used widely in electronic devices and incandescent street lights. Water samples for analyses of these inorganics were collected twice during the water year at most of the monitoring sites. At the National Stream Quality Accounting Network (NASQAN) stations, a federal funded water-quality program, the dissolved inorganics were analyzed two times a year. Some results are listed in table 2. Table 2.--Concentrations of dissolved inorganics at NASQAN Stations, micrograms per liter (ug/L). Station name Chromium Lead Mercury Rio Grande de Manati 1 2 0.2 Rio de la Plata 3 3 1.0 Rio Grande de Patillas 1 4 .3 Rio Grande de Afiasco 1 4 .1 11 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Thousands of different toxic organics are used today to control undesirable insects, weeds, rodents and fungi. These synthetic-organic pesticides can contribute significantly to the contamination of a stream or a body of water by their direct discharge, spray drift, treated land runoff, treated land erosion, atmospheric precipitation, accidental spills and leachates from garbage dumps and sanitary landfills. Water bodies may receive not only the toxic chemicals, but also the intermediary and accessory products of their synthesis. Water samples were collected once at selected sites for analyses on the most common organics. Lindane or chlordane, two synthetic organics, were detected in over 20 % of the sampled sites. The rest of the organics for which labora­ tory analyses were performed, did not exceed the analytical detection limits. In the proposed mining area, the water quality did not change significantly during the water year. Samples from two stations (Numbers 50021000, 50023000) do not show significant changes in pH, alcalinity, or concentration of selected ions. The measurements of some physical and chemical parameters can help in the determination if a body of water is fresh, salty or saline. Specific conductance, dissolved solids and chlorides concentration are among them. Water with a specific conductance around 50,000 umhos/cm and a chloride concentration of 19,300 mg/1 is said to be seawater. Dissolved solids are chiefly the mineral constituents dissolved from weathering or rocks and soils. Water containing more than 1,000 mg/1 are unsuitable for many purposes. The U.S. Geological Survey classifies the degree of salinity of these more mineralized bodies of water as follows (Swenson and Baldwin, 1965): Dissolved Solids, mg/1 Degree of salinity Less than 1,000 nonsaline 1,000 to 3,000 slightly saline 3,000 to 10,000 moderately saline 10,000 to 35,000 very saline Chloride is found in large amounts in ancient brines, seawater, sewage and industrial brines. About 300 mg/1 chloride in combination with sodium gives a salty taste to water. The maximum chloride concentration permissible in drinking water is 250 mg/1 (EPA, 1976). At Rio Hondo at Flood Channel near Catalio (50047530), and Bahia de San Juan No. 5 (50049920) salinities can fluctuate between nonsaline and very saline. 12 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 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 equivalent to 43,560 cubic feet or about 326,000 gallons or 1,233 cubic meters. Algae are mostly aquatic single-celled, colonial, or multicelled plants containing chlorophyll and lacking roots, stems, and leaves. 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, 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. Fecal coliform bacteria are bacteria that are present in the intestines or feces of warm-blooded animals. They are often used as indicators of the sanitary quality of the water. In the laboratory they are defined as all organisms which produce blue colonies within 24 hours when incubated at 44.5°C + 0.2°C on M-FC medium (nutrient medium for bacterial growth). Their concentrations are expressed as number of colonies per 100 mL of sample. Fecal streptococcal bacteria are bacteria found also in intestines of warm-blooded animals. Their presence in water is considered to verify fecal pollution. They are characterized as grampositive, coccie bacteria which are capable of growth in brain-heart infusion broth. In the laboratory they are definedas all the organisms which produce red or pink colonies within 48 hours at 35°C + 1.0°C on M-enterococcus medium (nutri- ent medium for bacterial growth). Their concentrations are expressed as number of colonies per 100 mL of sample. 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 13 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 at 35°C. In the laboratory these bacteria are defined as the organisms which produce colonies within 24 hours when incubated at 35°C + 1.0°C on M-Endo medium (nutrient medium for bacterial growth). Their concen­ trations are expressed as number of colonies per 100 mL of sample. Bed material is the unconsolidated material of which a streambed, lake, pond,reservoir, or estuary bottom is composed. Biochemical oxygen demand (BOD) is a measure of the quantity of dissolved oxygen, in milligrams per liter, necessary for the decomposition of organic matter by microorganisms, such as bacteria. 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 contained cells per sample, usually milliliters (mL) or liters (L). Cfs-day is the volume of water represented by flow or 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 2,447 cubic meters. Chlorophyll refers to the green pigments of plants. Chlorophyll a and b are the two most common pigments in plants. 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 saltwater. 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 feet per second per square mile (CFSM) is the average number of cubic feet or water flowing per second from each square mile of area drained, assuming that the runoff is distributed uniformly in time and area. Cubic foot per second (cu ft/s) is the rate of discharge representing a volume of 1 cubic foot passing a given point during 1 second and is equivalent to approximately 7.48 gallons per second or 448.8 gallons per minute or 0.02832 cubic meters per second. 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. 14 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Mean discharge (MEAN) is the arithmetic mean of individual daily mean discharges during a specific period. Instantaneous discharge is the discharge at a particular instant of time. Dissolved refers to the amount of substance present in true chemical solution. In practice, however, the term includes all forms of substance that will pass through a 0.45-micrometer membrane filter, and thus may include some very small (colloidal) suspended particles. Analyses are performed on filtered samples. Diversity index is a numerical expression of evenness of distribution of aquatic organisms. The formula for diversity index is: n -E i log7 ni i=1 n n Where n 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 specific 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 river above the specified point. Figures of drainage area given herein include all closed basins, or noncontribution areas, within the area unless otherwise noted. Drainage basin is a part of the surface of the earth that is occupied by a drainage system, which consists of a surface stream or a body of impounded surface water together with all tributary surface streams and bodies of impounded surface water. Gage height (G.H.) is the water-surface elevation referred to some arbitrary gage datum. Gage height is often used interchangeably with the more general term "stage," although gage height is more appropriate when used with a reading on a gage. Gaging station is a particular site on a stream, canal, lake, or reservoir where systematic observations of hydrologic data are obtained. Ground-water station is a well at which observations of ground-water level are made, either continuously by recorder, or periodically by hand. In addition, various chemical or physical parameters may be obtained, usually on a periodic basis. Hardness of water is a physical-chemical characteristic that is commonly recognized by the increased quantity of soap required to produce lather. It is attributable to the presence of alkaline earths (principally calcium and magnesium) and is expressed as equivalent calcium carbonate (CaCO). 15 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Micrograms per gram (ug/g) is a unit expressing the concentration of a chem­ ical element as the mass (micrograms) of the element sorbed per unit mass (gram) of sediment. Micrograms per liter (UG/L, ug/L) is a unit expressing the concentration of chemical constituents in solution as mass (micrograms) of solute per unit volume (liter) of water. One thousand micrograms per liter is equivalent to one milligram per liter. Milligrams per liter (MG/L, mg/L) is a unit for expressing the concentration of chemical consitutents 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 3. TABLE 3.--Factors for conversion of chemical constituents in milligrams per liter to milliequivalents per liter. Ion Aluminum (A1+3) * Ammonia as NH4+1 Barium (Ba+2) Bicarbonate (HCO3-1) Bromide (Br-1) Calcium (Ca+2) Carbonate (CO3-2) Chloride (CI-1) Chromium (Cr+6 )* Cobalt (Co+2)* Copper (Cu+2)* Cyanide (CN-1)* Fluoride (F-1) Hydrogen (H+1 ) Hydroxide (OH-1) Multiply by 0.11119 .05544 .01456 .01639 .01251 .04990 .03333 .02821 .11539 .03394 .03148 .03844 .05264 .99209 .05880 Ion Multiply by Iodide (I-1) 0.00788 Iron (Fe+3)* .05372 Lead (Pb+2)* .00965 Lithium (Li+1)* .14411 Magnesium (Mg+2) .08226 Manganese (Mn+2)* .03640 Nickel (Ni+2)* .03406 Nitrate (NO3-1) .01613 Nitrite (NO2-1) .02174 Phosphate (PO4-3) .03159 Potassium (K+1) .02557 Sodium (Na+1 ) .04350 Strontium (Sr+2)* .02283 Sulfate (SO4-2) .02082 Zinc (Zn+2)* .03060 * Constituent reported in micrograms per liter; multiply by factor and divide results by 1,000. Organism is any living entity, such as an insect, phytoplankter, or zoo­ plankter. Organism count/area refers to the number of organisms collected nnd enumerated in a sample and adjusted to the number per area habitat, usually square meters (m ), acres, or hectares. Periphyton, benthic organisms, and macrophytes are expressed in these terms. Organism count/volume refers to the number of organisms collected and enu­ merated 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. 2 16 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Total organism count is the total number of organisms collected and enumerated in any particular sample. Partial-record station is a particular site where limited streamflow 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 suspended sediment or bed material determined by either sieve or sedimentation methods. Sedimen­ tation 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 recommendations made by the American Geophysical Union Subcommittee on Sediment Terminology. 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 material 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. 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. Pesticides are chemical compounds used to control undesirable plants and animals. Major categories of pesticides include insecticides, miticides, fungicides, herbicides, and rodenticides. Insecticides and herbicides, which control insects and plants, respectively, are the two categories reported. 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. Phytoplankton growth is dependent upon solar radiation and nutrient substances. 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. 17 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Blue-green algae are a group of phytoplankton organisms having a blue pigment, in addition to the green pigment called chlorophyll. Blue-green often cause nuisance conditions in water. Diatoms are the unicellular or colonial algae having a siliceous shell. Their concentrations are expressed as number of cells/mL of sample. Green algae have chlorophyll pigments similar in color to those of higher green plants. Some forms produce algal mats or floating "moss" in lakes. Their concentrations are expressed as number of cells/mL of sample. Polychlorinated biphenyls (PCBs) are industrial chemicals that are mixtures of chlorinated biphenyl compounds having various percentages of chlorine. They are similar in structure to organochlorine insecticides. 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. Sediment is solid material that originates mostly from disintegrated rocks and is transported by, suspended in, or deposited from water; it includes 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. Suspended sediment is the sediment that at any given time is maintained in suspension by the upward components of turbulent currents or that exists in suspension as a colloid. Suspended-sediment concentration is the velocity-weighted concentration 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). Suspended-sediment discharge (tons/day) is the rate at which dry weight of sediment passes a section of a stream or is the quantity of sediment, as measured by dry weight or volume, that passes a section in a given time. It is computed by multiplying discharge times concentration times 0.0027. The suspended-sediment concentration (mg/L) and suspended-sediment discharge (tons/day) except in stations 50028000 and 50071000 are based on instantaneous discharge and do not necessarily represent the actual daily discharge of suspended sediment. Suspended-sediment load is quantity of suspended sediment passing a sec­ tion in a specified period. 18 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Total sediment discharge (tons/day) is the sum of the suspended-sediment discharge and the bed-load discharge. It is the total quantity of sedi­ ment, as measured by dry weight or volume, that passes a section during a given time. Mean concentration is the time-weighted concentration of suspended sediment passing a stream section during a 24-hour day. Solute is any substance derived from the atmosphere, vegetation, soil, or rocks 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 micromhos 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. Streamflow 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 "stream­ flow" is more general than "runoff" as streamflow may be applied to discharge whether or not it is affected by diversion or regulation. 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. The water-sediment mixture is associated with (or sorbed on) that material re­ tained on a 0.45 micrometer filter. 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. Tons per acre-foot indicates the dry mass of dissolved solids in 1 acre-foot of water. It is computed by multiplying the concentration in milligrams per liter by 0.00136. Tons per day is the quantity of substance in solution or suspension that passes a stream section during a 24-hour day. 19 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Total load (tons) is the total quantity of any individual constituent, as measured by dry mass or volume, that is dissolved in a specific amount of water (discharge) during a given time. It is computed by multiplying the total discharge, times the mg/L of the constituent, times the factor 0.0027, times the number of days. Taxonomy is the division of biology concerned with the classification and naming of organisms. The classification of organisms is based upon a hier­ archical 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, limbata is the following: Kingdom Animal Phylum Arthropoda Class Insecta Order Ephemeroptera Family Ephemeridae Genus Hexagenia Species....Hexagenia limbata 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. Thus, the water year beginning October 1, 1976 and ending September 30, 1977 is called the "1977 water year." Weighted average is used in this report to indicate discharge-weighted average for days 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. WRD is used as an abbreviation for "Water-Resources Data" in the REVISED RECORDS paragraph to refer to State annual basic-data reports published before 1975. WSP is used as an abbreviation for "Water-Supply Paper" in references to previously published REPORTS. DOWNSTREAM ORDER AND STATION NUMBER 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. 20 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 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 dis­ tinction is made between partial-record stations and other stations; there­ fore, the station number for a partial-record station indicates downstream order position in a list made up of both types of stations. Gaps are left in the series of numbers to allow for new 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." NUMBERING SYSTEM FOR WELLS AND MISCELLANEOUS SITES 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. 6, below). 66°53' 52' 5" 50' 49' 48' 66°47' 18°02 01' 134 132.1 -70 131 \ • 27 .74 ...„ COORDINATES FOR WELLS 27 (180150066474901), AND 74 (180110066473501). COORDINATES FOR WELLS 132 (180133066503301), AND 134 (180120066503201). 18° 00' 17°59 •Ir 16 0 .*/ COORDINATES FOR WELL 131 (180058066502701) COORDINATES FOR WELL 16 (175922066495901). Figure 6.--System for numbering wells and miscellaneous sites (latitude and longitude). SPECIAL NETWORKS AND PROGRAMS National stream-quality accounting network (NASQAN) is a data collection net­ work designed by the U.S. Geological Survey to meet many of the information demands of agencies or groups involved in national or regional water-quality planning and management. Both accounting and broad-scale monitoring objectives 21 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 have been incorporated into the network design. Areal configuration of the network is based on river-basin accounting units (identified by 8-digit hydrologic-unit numbers) designated by the Office of Water Data Coordination in consultation with the Water Resources Council. Primary objectives of the network are (1) to depict areal variability of streamflow and water-quality conditions nationwide on a year-by-year basis and (2) to detect and assess long-term changes in streamflow and stream quality. Pesticide program is a network of regularly sampled water-quality stations where samples are collected to determine the concentration and distribution of pesticides in streams where potential contamination could result from the application of the commonly used insecticides and herbicides. Operation of the network is a Federal interagency activity. 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 precipitation stations. The purpose of the precipitation stations is to provide an estimate sufficient for hydrologic studies of the tritium input to the United States. EXPLANATION OF STAGE AND WATER-DISCHARGE RECORDS Collection and computation of data The base data collected at gaging stations consist of records of stage and measurements of discharge of streams. In addition, observations of factors affecting the stage-discharge relation or the weather records, and other information are used to supplement base data in determining the daily flow. Records of stage are obtained either from direct readings on a nonrecording gage or from a water-stage recorder that gives either a continuous graph of the fluctuations or a tape punched at selected time intervals. Measurements of discharge are made with a current meter, using the general methods adopted by the Geological Survey. 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. For stream-gaging stations, rating tables giving the discharge for any stage are prepared from stage-discharge relation curves. If extensions to the rating curves are necessary to express discharge greater than measured, they are made on the basis of indirect measurements of peak discharge (such as slope-area or contracted-opening measurements, computation of flow over dams or weirs), step-backwater techniques, velocity-area studies, and logarithmic plotting. The daily mean discharge is computed from gage heights and rating tables, then the monthly and yearly mean discharge are computed from the daily figures. If the stage-discharge relation is subject to change because of frequent or continual change in the physical features that form the control, the daily mean discharge is computed by the shifting-control method, in which correction factors based on individual discharge measurements and notes by engineers and observers are used in applying the gage heights to the rating tables. If the stage-discharge relation for a station is temporarily changed 22 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 by the presence of aquatic growth or debris on the control, the daily mean discharge is computed by what is basically the shifting-control method. At some stream-gaging stations the stage-discharge relation is affected by the backwater from reservoirs, tributary streams, or other sources. This neces­ sitates 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 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 dis­ charge. 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 dis­ charges are estimated on the basis of recorded range in stage, prior and subsequent records, discharge measurements, weather records, and comparison with records for other stations in the same or nearby basins. The data in this report generally comprise a description of the station and tabulations of daily and monthly figures. For gaging stations on streams a table showing the daily discharge and monthly and yearly discharge is given. Records are published for the water year, which begins on October 1 and ends on September 30. The description of the gaging station gives the location, drainage area, period of record, notations of revisions of previously published records, type and history of gages, general remarks, average discharge, and extremes of discharge or elevation. The location of the gaging station and the drainage area are obtained from the most accurate maps available. River mileage, given under "LOCATION" for some stations, is that determined and used by the Corps of Engineers or other agencies. Periods for which there are published records for the present station or for stations generally equivalent to the present one are given under "PERIOD OF RECORD." Previously published streamflow records of some stations have been found to be in error on the basis of data or information later obtained. Revisions of such records are usually published along with the current records in one of the annual or compilation reports. In order to make it easier to find such revised records, a paragraph headed "REVISED RECORDS" has been added to the description of all stations for which revised records have been published. Listed therein are all the reports in which revisions have been published, each followed by the water years for which figures are revised in that report. In listing the water years only one number is given; for instance, 1965 stands for the water year October 1, 1964, to September 30, 1965. If no daily, monthly, or annual figures of discharge are affected by the revision, the fact is brought out by notations 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 revised figure was first published is given. It should be noted that for all 23 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 stations for which cubic feet per second per square mile and runoff in inches are published, a revision of the drainage area necessitates corresponding revision of all figures based on the drainage area. Revised figures of cubic feet per second per square mile and runoff in inches resulting from a revision of the drainage area only are usually not published in the annual series of reports. The type of gage currently in use, the datum of the present gage above mean sea level, and a condensed history of the types, locations, and datums of previous gages used during the period of record are given under "GAGE." In references to datum of gage, the phrase "mean sea level" denotes "Sea Level Datum of 1929" as used by the Topographic Division of the Geological Survey unless otherwise qualified. Information pertaining to the accuracy of the discharge records and to condi­ tions which affect the natural flow of the gaging station is given under "REMARKS." For reservoir stations information on the dam forming the reser­ voir, the capacity, outlet works and spillway, and purpose and use of the reservoir is given under "REMARKS." The average discharge for the number of years indicated is given under "AVER­ AGE DISCHARGE"; it is not given for stations having fewer than 5 complete years of record or for stations where changes in water development during the period of record cause the figure to have little significance. In addition, the median of yearly mean discharges is given for stream-gaging stations having 10 or more complete years of record if the median differs from the average by more than 10 percent. Under "EXTREMES" are given first, the extremes for the period of record, second, information available outside the period of record, and last, those for the current year. Unless otherwise qualified, the maximum discharge (or contents) is the instantaneous maximum corresponding to the crest stage obtained by use of a water-stage recorder (graphic or digital), a crest-stage gage, or a nonrecording gage read at the time of the crest. If the maximum gage height did not occur on the same day as the maximum discharge (or contents), it is given separately. Similarly, the minimum is the instantaneous minimum unless otherwise qualified. For some stations peak discharges are listed with EXTREMES FOR THE CURRENT YEAR; if they are, all independent peaks including the maximum for the year, above the selected base with the time of occurrence and corresponding gage heights are published in tabular format. The base discharge, which is given in the table heading, is selected so that an average of about three peaks a year will be presented. Peak discharges are not published for any canals, ditches, drains, or for any stream for which the peaks are subject to substantial control by man. Time of day is expressed in 24-hour local standard time; for example, 12:30 a.m. is 0030, 1:30 p.m. is 1330. The minimums for these stations are published in a separate paragraph following the table of peaks. 24 WATER RSOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 The daily table for stream-gaging stations gives the 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 may be 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 regulation or diversion, if the drainage area includes large noncontributing areas, or if the average annual rainfall over the drainage basin is usually less than 20 inches. In the yearly summary below the monthly summary, the figures shown are the appro­ priate daily discharges for the calendar and water years. Footnotes to the table of daily discharge are introduced by the word "NOTE." Footnotes are used to indicate periods for which the discharge is computed or estimated by special methods because of no gage-height record, backwater from various sources, or other unusual conditions. Periods of no gage-height record are indicated if the period is continuous for a month or more or in­ cludes the maximum discharge for the year. Period of backwater from an unusual source, or indefinite stage-relation, or of any other unusual condi­ tion at the gage site are indicated only if they are a month or more in length and the accuracy of the records is affected. The methods used in computing discharge for various unusual conditions have been explained in preceding paragraphs. Data collected at partial-record water-quality stations follows the informa­ tion for continuous-record sites. Data for partial-record discharge stations are presented in one table. This table shows the annual maximum stage and discharge at crest-stage stations. Accuracy of field data and computed results The accuracy of streamflow data depends primarily on (1) the stability of the stage-discharge relation or, if the control is unstable, the frequency of dis­ charge measurements, and (2) the accuracy of observations of stage, measure­ ments of discharge, and interpretations of records. The station description under "REMARKS" states the degree of accuracy of the records. "Excellent" means that about 95 percent of the daily discharges are within 5 percent; "good," within 10 percent; and "fair" within 15 percent. "Poor" means that daily discharges have less than "fair" accuracy. Figures of daily mean discharge in this report are shown to the nearest hundredth of a cubic foot per second for discharges of less than 1 cu ft/s; to tenths between 1.0 and 10 cu ft/s; to whole numbers between 10 and 1,000 cu ft/s; and to 3 significant figures above 1,000 cu ft/s. The number of signifi­ cant figures used is based solely on the magnitude of the figure. The same rounding rules apply to discharge figures listed for partial-record stations. 25 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Other data available Information of a more detailed nature than that published for most of the gaging stations such as observations of water temperatures, discharge measure­ ments, gage-height records, and rating tables is on file in the district office. Also, most gaging-station records are available in computer-usable form and many statistical analyses have been made. Information on the availability of unpublished data or statistical analyses may be obtained from the district office. Access to WATSTORE Data The National WATer Data STOrage and REtrieval System (WATSTORE) was estab­ lished 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 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 EXPLANATION OF WATER-QUALITY RECORDS Collection and examination of data Surface-water samples for analyses usually are collected at or near gaging stations. The quality-of-water records are given immediately following the discharge records at these stations. The descriptive heading for water-quality records gives the period of record for all water-quality data; the period of daily record for parameters that are measured on a daily basis (sediment discharge); extremes for the period of daily record; extremes for the current year; and general remarks. For ground-water records, no descriptive statements are given; however, the well number, date of sampling/and or other pertinent data are given in the table containing the chemical analyses of the ground water. 26 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Water analysis Most methods for collecting and analyzing water samples are described in the U.S. Geological Survey Techniques of Water-Resources Investigations. One sample can define adequately the water quality at a given time if the mixture of solutes throughout the stream cross sections is homogeneous. However, the concentration of solutes at different locations in the cross section may vary widely with different rates of water discharge, depending on the source of material and the turbulence and mixing of the stream. Some streams must be sampled through several vertical sections to obtain a representative sample needed for an accurate mean concentration and for use in calculating load. 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 possi­ ble, consistent with available sampling techniques and methods of analysis. In the rare case where an apparent inconsistency exists between a reported pH value and the relative abundance of carbon dioxide species (carbonate and bicarbonate), the inconsistency is the result of a slight uptake of carbon dioxide from the air by the sample between measurement of pH in the field and determination of carbonate and bicarbonate in the laboratory. Water temperature Water temperatures were measured at all water-quality stations. In addition, temperatures were taken during 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 diel 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. Table 4.--Conversion of Temperature Scales Degrees Celcius (°C) to Degrees Farenheit (°F) °C °F °C °F °C °F 15.0 59 21.0 70 27.0 81 15.5 60 21.5 71 27.5 82 16.0 61 22.0 72 28.0 82 16.5 62 22.5 72 28.5 83 17.0 63 23.0 73 29.0 84 17.5 64 23.5 74 29.5 85 18.0 64 24.0 75 30.0 86 18.5 65 24.5 76 30.5 87 19.0 66 25.0 77 31.0 88 19.5 67 25.5 78 31.5 89 20.0 68 26.0 79 32.0 90 20.5 69 26.5 80 °F = 9/5 (°C) + 32 or * °C = 5/9 (°F - 32) 27 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Sediment Suspended-sediment concentrations are determined from water-sediment samples collected by using depth-integrating or automatic sediment samplers. Samples usually are obtained at several verticals in the cross section, or a single sample may be obtained at a fixed point and a coefficient applied to determine the mean concentration in the cross sections. During periods of rapidly changing flow or rapidly changing concentration, samples may have been collected more frequently (twice daily or, in some instances, hourly). The published sediment discharges for days of rapidly changing flow or concentration were computed by the subdivided day method (time-discharge weighted average). Therefore, for those days when the 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 loads of suspended sediment were estimated on the basis of water discharge, sediment concentrations observed immediately before and after the periods, and suspended-sediment loads for other periods of similar discharge. At other stations, suspended-sediment samples were collected periodically at many verticals in the stream cross section. Although data collected period­ ically may represent conditions only at the time of observations, such data are useful in establishing seasonal relations between quality and streamflow in predicting long-term sediment-discharge characteristics of the stream. In addition to the records of the amounts of suspended sediment, records of the periodic measurements of the particle-size distribution of the suspended sediment and bed material are included. EXPLANATION OF GROUND-WATER LEVEL RECORDS Collection of the data 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. 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 6. Measurements are made in many types of wells, under varying conditions of access and at different temperatures; hence, neither the method of measurement nor the equipment can be standardized. At each observation well, however, the equipment and techniques used are those that will ensure that measurements at each well are consistent. 28 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1983 Water-level measurements in this report are given in feet with reference either to mean sea level (msl) or land-surface datum (lsd). Mean sea level is the datum plane on which the national network of precise levels is based; land-surface datum is a datum plane that is approximately at land surface at each well. If known, the altitude of the land-surface datum is given in each well description. The height of the measuring point (M.P.) above or below low-surface datum is given in each well description. Water levels in wells equipped with recording gages are reported for every day. 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 in 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 are reported to a hun­ dredth of a foot, but some are given only to a tenth of a foot or a large unit. Surface and Quality-of--Water Records for Puerto Rico 67°15' 67°00' 45' 30' 15' 66°00' 45' 65°30' OCEANO ATLANTICO Go „No ,00 oo 1, 4.; Gad 04' ..Ct ,oz1, ,z,s is C?aa O, t 1" 0 v bt 1/40 10 v 1,0 e b te 1/40.e e 18°30' 0 is.,be io to 8:r 0 038 • 395 Rio Culebrinas 027750 0460 Rio Guayabo 0284 1478 Rio Grand A (I t 832 0670 0350 655 Rio Fajardo 0618• 634 0 1440 0280 07 • Rio Grande 0570 15' de Aliasco 14 1 05 0564 Rio Yaguez 1 15 141 • 0 6 Rio Daguao Quebrada Palma Rio Guanafibo 1380 1425 1360 0430 0513 \ Rio Santiago 0.09 Rio Blanco 11 • 5 1 I5 • Rio Anton Ruiz Rio Humacao 26 5 • • _A128950 1 4 0 2 0905 Rio Guayands 18°00' 1293£ ft • to,‘0 4 i 1 j, 0 0 Abe'c, , ,z,e 6 c; o \f, 0 0 ,ocs ac. 0 0 o ote. 0 0,1°oes c• 0 ie 0 ea .0 so 0 G anti 0 * ic. 00 040 04 *0 0 Ne° A 0 4% EXPLANATION i1/4 1* 0 4/ 4 I* CPI' 4% ko .. ,0 1/40 143 0\0 ec'Z'ab C ,CP V ) r2 o SURFACE WATER STATIONS 41' 41* k0 (i‘ 8 0 0 4 \ q (2.0 1. 4/ t.„, i' R*% IS i s I •0* 11/0 4 I‘ 1%0 O CONTINUOUS STREAMFLOW -1125 17045' STATION O 10 20 30 KILOMETERS I • 1411 LAKE-ELEVATION STATION O 10 20 MILLS MAR CARIBE Figure 7.--Continuous surface-water stations in Puerto Rico. 67°15' 67°00' 45' 30' 15' 66°00' 45' 65°30' T OCEAN° ATLANTICO cs0 .1. o o 0 ,9 , e. 4-039750 q i 0 0 0* so v 0 0A, o 0e cr et" 000 0 0397 , $ bil) ,0 \O 00be \O p 039650 6- e \e, 18°30' q`s 4q• be 00, ,.0R 0 ik` 0114 ,• 38 0290 0395 11 47530 Rio Culebrinas 4982 0381 0460 011• 0284 Rio Guayabo 1491 0491 04851 • 04799 59 Rio Grand 010790 06 010720 027250 0383 0 044 • 0 0 8 059 090 a 0725 b Fajardo 76 O "44 0588 144 • 116, 0280 03 554 251 0 A Rio Grande • 3 950 0575 07 0 4 10 15 de Afiasco 0 5525 • 02 0 025 47Er 1388 02 Ir0307 055 Rio Yaguez 3 66 7 to Daguao • - 15 Rio Guanafibo 136 02 • ir--0210 Quebrada Palma 0 = 2 ► \ Rio Santiago 13 0 0430 cy( 0.0 5 Rio Blanco 1 4 336 Rio Anton Ruiz 1 k 03995 •8 c 5 Rio Humacao 1965 ? 039 \ N 0 in f y 1 ,47 10 18°00' 1162 I . 1 IP 0 o04\ 6 0 • o EXPLANATION 00 2, +o 04 00 ,Qo 40 0 I. 0, ip ika.,0 eGo ‘P SOQ e s- 0 se, to QUALITY-OF-WATER STATIONS o 00A0v.cisoe 1)0‘00000v, o‘ 00-0-cp b vi 4z.‘ .0 0 Q. g.ilso e 1/40 0 Is IV 0430 BIOLOGICAL R.\ R. i'. 40 i1/0 4 i k cf 0820 CHEMICAL \O 'tik 17°45' • 110 20 30 KILOMETERS 1 0710 SEDIMENT (DAILY) O 10 20 MILES MAR CARIBE V-0910 SEDIMENT (MONTHLY) Figure 8.--Water-Quality stations in Puerto Rico. 66'00' 65'45' SAN JUAN 0475.25 0496 0493.10 665 0693.50 0485.10 0.15 0610 66 0690 602 0638 .0 06 0475.04 0; 2 0 5.40 Fajardo 0:94 to Fajardo 6 0720 . 0584 0570.15 07 0554.10 eib X 553.1 32 0566 Cagua 0565.50 29 0527 0535 555 0556 0770 0775 0776 073 0740.10 0511.40 0785.10 Rio Anton Ruiz Rio Humacao EXPLANATION SURFACE WATER STATIONS 0 19.50 0865 0857 0872 A0825 LOW-FLOW STATION 41159 CREST-STAGE GAGING STATION 18•00' 942.A 0943 A 0915 0910 0850 0851 10 20 KILOMETERS 10 20 MILES Figure 9.--Low-flow partial-record stations in Eastern Puerto Rico. 15 67°15' 67°00' 45' 30' 15' 66°00' 45' 65°30' OCEANI C) ATLANTIC° 66% 4e et. e 604' e 0,3 18°30' R. be p Rio Culebrinas Rio Guayab Rio Grand Rio Grande de Afiasco Rio Yaguez Rio Daguao Quebrada Palma Rio Guanallbo \ Rio Santiago Rio Blanco Rio Anton Ruiz Rio Humacao Rio Guayana's 18°00' 0 ,22#660 4 0 0 0* j,e,43 IkO'ilas oore 0 d&.A A so ok 1.•,, tO 1ov e ° AV \OW 4 W I Or 0if '0 OV vo A A + 0 ga* 40 4420 A%0 ‘.0 „N. 00 t S c,6 ko -6 011' 1/0 4 quto:n` r I. ko v. trip e p 1/0 4 q'he is` - i1/4 42. R• 0 so 0- 42. 424 40 17°45' 0 10 20 3:3 KILOMETERS 0 10 20 MILES MAR CARIBE Figure 10.--Partial-record stations in Central and Western Puerto Rico. 35 OCEANO ATLANTIC 0 ISABELA UE BRADILLAS 0114 A. oi rsioh • 164 AGUADILLA • 166 0110 010790 Drainage boundaries indeterminate in limestone terrane LaVfica 010720 Limestone Igneous sedimentary rocks LARES 0106-- Rio Culebrin basin Rio Grande de 1,.cti Artiasco basin • EXPLANATION A 0114 LOW-FLOW STATION AND NUMBER 11, 0105 QUALITY-OF-WATER STATION AND NUMBER • 164 WELL AND WELL NUMBER Map area 0 I 2 TKILOMETERS I i l l 1 0 SMILES Figure 11.--Rio Guajataca basin. 36 RIO GUAJATACA BASIN 50010500 RIO GUAJATACA AT LARES, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°18'01", long 66°52'24", at bridge on Highway 111 (km 32.9), 0.1 mi (0.2 km) upstream from Quebrada Anion, and 0.4 mi (0.6 km) northeast of Lares Plaza. DRAINAGE AREA.--3.16 sq mi (8.18 sq km). PERIOD OF RECORD.--Water years 1958-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLT- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN. (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- On- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 10... 1115 5.1 255 7.7 23.0 12 7.2 86 13 K66000 25000 JAN , 1983 31... 1425 1.5 243 7.3 21.0 1.6 9.4 108 12 540 1200 MAR 23... 1045 1.3 280 7.6 23.0 <1.0 7.0 84 14 5700 64000 MAY 11... 1300 3.6 245 7.5 25.0 3.4 7.8 98 <10 K1500 3500 AUG 24... 1130 2.7 234 8.0 24.0 1.9 11.2 137 16 K1300 570 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS. CALCIUM SIUM, SODIUM, AD- SIUMr LINITY SULFATE RIDE. RIDE, NESS NONCAR- DIS- DIS... DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1932 10... -- 87 JAN , 1983 31... 90 1 26 6.2 14 .7 2.0 90 9.0 9.2 .40 MAR 23... 130 MAY 11... 93 0 28 5.6 11 .5 2.9 93 15 11 .10 AUG 24... 95 2 28 6.0 12 .6 2.1 93 3.2 11 .20 SOLIDS. SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L 015- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV r 1982 10... 16 1.5 .020 1.5 <.010 1.3 1.30 2.8 JAN r 1933 31... 31 152 .62 5 1.1 .020 1.1 .020 .18 .20 1.3 MAR 23... 4 .75 .050 .80 .090 .21 .30 1.1 MAY 11... 25 154 1.5 8 1.1 (.010 1.1 <.010 .19 .20 1.3 AUG 24... 28 151 1.1 6 1.0 .060 1.1 .C3C .47 .50 1.6 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GIN, PHORUS, ASENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV 1982 10... 12 .110 JAN . 1983 31... 5.8 .100 2 ZOO 2 3 7 .4 <1 2 MAR 23... 4.9 .240 MAY 11... 5.8 .060 AUG 24... 7.1 .110 2 100 <1 <1 9 <.1 <1 K = non-ideal count RIO GUAJATACA BASIN 37 50011000 CANAL PRINCIPAL DE DIVERSIONES AT LAGO DE GUAJATACA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°24'02", long 66°55'27", off Highway 476 at Lago Guajataca outlet, 3.0 mi (4.8 km) southwest of Segunda Unidad Baldorioty de Castro, and 5.3 mi (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 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND. FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL. FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (8G/L) ATION) (MG/L) 100 ML) 100 ML) OCT • 1982 01... 1020 50 322 7.1 25.0 1.5 .9 11 37 K10 K13 NOV 18... 1250 50 320 7.1 25.0 3.1 .0 0 23 K170 52 JAN . 1983 20... 1110 59 303 7.3 25.0 1.0 2.5 31 26 K5 K4 MAR 30... 1300 45 305 7.8 27.0 1.0 6.4 82 <10 K100 K100 MAY 23... 1420 40 323 7.1 255 1.9 2.0 2810 <10 92 310 AUG 26... 1005 55 309 7.5 27.0 2.2 2.1 27 20 500 260 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS. CALCIUM SLUM. SODIUM. AD- SIUM. LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD On- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) OCT . 1982 01... 150 43 56 3.1 4.4 .2 1.8 110 7.0 6.7 .10 NOV 18... 150 JAN , 1983 20... 140 0 49 3.6 5.4 .2 1.9 140 8.0 7.8 .10 MAR 30... 130 MAY 23... 150 9 54 3.4 4.8 .2 1.9 140 13 8.0 .10 AUG 26... 150 6 54 3.7 5.9 .2 1.4 143 12 8.5 .10 SOLIDS, SOLIDS. NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN. GEN• GEN. MONIA + SOLVED TUENTS. SOLVED DEG. Cs NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDEO (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) NITRO- GEN. TOTAL (MG/L AS N) OCT r 1982 01... 6.3 151 20.4 3 <.010 <.10 .050 .45 .50 NOV 13... 6 <.010 <.10 .500 1.2 1.70 JAN , 1983 20... 1.7 161 25.8 2 .010 <.10 .040 .36 .40 MAR 30... 1 <.010 <.10 <.010 .30 MAY 23... 5.1 174 18.8 6 .47 .030 .50 .470 .63 1.10 1.6 AUG 26... 6.2 178 26.5 6 <.010 <.10 .150 .35 .50 NITRO- GEN, TOTAL (MG/L DATE AS NO3) CHRO- BARIUM, CADMIUM MIUM. LEAD, MERCURY PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS P) AS AS) AS BA) AS CD) AS CR) AS PS) AS HG) SELE- NIUM, TOTAL (UG/L AS SE) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) OCT • 1982 01... .030 3 100 1 <1 2 .2 <1 <1 NOV 18... .040 JAN . 1983 20... .060 3 <100 1 3 13 .3 <1 <1 MAR 30... <.010 MAY 23... 7.1 .010 AUG 26... .030 3 100 1 <1 7 <.1 <1 <1 K = non-ideal count 38 RIO GUAJATACA BASIN 50011400 RIO GUAJATACA ABOVE MOUTH NEAR QUEBRADILLAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°28'31", long 66°57'46", at ford, 1.7 mi (2.7 km) upstream from bridge on Highway 2, 2.1 mi (3.4 km) from the Atlantic Ocean, 6.6 mi (10.6 km) downstream from Lago Guajataca, and 1.6 mi (2.6 km) west of Quebradillas Plaza. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAO. 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT , 1982 01... 0825 11 533 7.2 24.0 <1.0 3.3 40 26 200 240 NOV 13... 1125 71 408 7.8 24.0 4.0 8.2 99 22 530 490 JAN , 1933 20... 0905 18 314 7.4 23.5 1.0 6.3 74 28 54 590 MAR 30... 1045 11 425 7.6 25.0 <1.0 7.1 86 16 K530 1300 MAY 12... 1510 11 510 7.6 26.0 .30 8.4 104 16 100 110 AUG 26... 0820 12 530 7.8 24.5 <1.0 3.8 46 20 60 550 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- ors- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) OCT , 1982 01... 230 18 77 8.6 13 .5 1.3 210 8.0 33 <.10 NOV 13... 170 JAN , 1983 20... 190 0 64 7.2 16 .5 1.3 190 9.0 23 <.10 MAR 30... 180 MAY 12... 210 1 71 3.1 13 .6 1.3 210 11 35 <.10 AUG 26... 230 20 78 9.0 20 .6 1.0 212 8.8 33 <.10 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SCLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- HS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. C. NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN. (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (PG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) OCT , 1982 01... 5.7 278 8.2 4 1.7 .020 1.7 .040 .06 .10 1.8 NOV 18... 6 <.010 .70 .030 1.7 1.70 2.4 JAN , 1983 20... 5.6 240 11.7 2 <.010 1.6 .040 3.4 3.40 5.0 MAR 30... 2 1.3 .010 1.3 .010 .19 .20 1.5 MAY 12... 5.5 276 8.2 3 1.7 <.010 1.7 <.01C .09 .10 1.8 AUG 26... 6.4 283 9.2 4 2.1 .040 2.1 .020 .28 .30 2.4 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L GATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) OCT , 1982 01... 8.0 .010 2 100 1 <1 2 .2 <1 <1 NOV 18... 11 .020 JAN , 1983 20... 22 .010 2 <100 1 3 10 .2 <1 <1 MAR 30... 6.6 <.010 MAY 12... 8.0 .010 AUG 26... 11 .030 2 100 1 <1 5 <.1 <1 <1 K = non-ideal count I 39 OCEAN° ATLANTIC° QUEBRADILLAS E ARECIBO Drainage bounanries indeterminate esione terrune • Bayaney River underground Limestone Igneous and sedimen tar y rocks LARES Rfboain " Rio Tanana: R(o Grande de UTUADO I Arecibo basis Drainage boundary Atidsco desk, Gronds de EXPLANATION A 0158 LOW-FLOW STATION AND NUMBER TKILOmETERS 1 MILES Figure 12.--Rio Camuy basin. I  41 OCEANO ATLANTICO • HATILLO ARECIB BARCELONE TA 0284 027750 eBayaney eFlorida Drainage boundaries indeterminate in limestone terrane Limestone Logo UTUADO 0215 Logo Viv as .41PUYD Tu .. !!„. 02n Adjuntos Rio Grande du Alicia° basin cleADJUNTAS Rio inabon Rio Bucandbasin basin EXPLANATION A 0284 SURFACE-WATER STATION AND NUMBER Rio Guayonillo basin Rio Tallobo° basin • 0205 QUALITY-OF-WATER STATION AND NUMBER 161 WELL AND WELL NUMBER Map area SAN JUAN ?KILOMETERS SMILES Figure 13.--Rio Grande de Arecibo basin. 42 RIO GRANDE DE ARECIBO BASIN 50020500 RIO GRANDE DE ARECIBO NEAR ADJUNTAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°10'54", long 66°44'12", at Highway 135 bridge, 1.0 mi (1.6 km) upstream from Lago Adjuntas, and 1.5 mi (2.4 km) northwest of Adjuntas. DRAINAGE AREA.--12.7 sq mi (32.9 sq km) this does not include 6.0 sq mi (15.6 sq km) above Lago Garzas. PERIOD OF RECORD.--Water years 1969-74, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN. OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL. FECAL, FLOM, CON- PH TUR- OXYGEN. (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-Mc (COLS. TIME TANEOUS ANCE ARO ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMMOS) UNITS) (DEG C) (NTU) (MG/L) ATION) CMG/L) 100 ML) 100 ML) NOV r 1982 09... 0930 16 336 7.8 22.0 2.9 8.1 97 42 5000 4500 JAN • 1983 18... 0905 13 540 7.7 19.0 2.0 8.2 93 22 k16000 8600 MAR 17... 1435 15 320 7.6 26.0 7.2 7.1 93 29 k1800 5700 MAY 09... 1545 17 300 8.6 23.0 1.2 9.0 122 23 3200 3100 AUG 23... 0825 17 328 7.9 22.0 6.0 10.4 125 24 (14000 K12000 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS. CALCIUM SIUM, SODIUM. AD- SIUM, LINITY SULFATE RIDE. RIDE. NESS NONCAR- DIS- ors- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS k) CAC03) AS SO4) AS CL) AS F) NOV • 1982 09... JAN .1983 18... 120 MAR 17... MAY 09... 100 AUG 23... 110 110 5 23 11 65 2.8 2.9 110 10 89 .10 98 3 26 9.2 20 .9 2.3 100 12 28 <.10 4 29 10 20 .8 1.7 110 9.9 27 .10 SOLIDS. SOLIDS. NITRO- SILICA., SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN.AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN. GEN. GEN, MONIA + SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC (NG/L CIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE 5102) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) NITRO- GEN, TOTAL (MG/L AS N) NOV e 1932 09... 10 .71 .090 .80 .150 .95 1.10 1.9 JAN r 1983 18... 25 300 10.5 2 .80 .100 .90 .130 .42 .60 1.5 MAR 17... 8 .82 .080 .90 .390 .41 .80 1.7 MAY 09... 26 183 8.5 6 .66 .240 .90 .070 .63 .70 1.6 AUG 23... 30 194 8.9 12 1.1 .020 1.1 .200 .20 .40 1.5 C4R0- BARIUM, CADMIUM MIUM, LEAD, MERCURY NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL ERASLE ERABLE ERABLE ERABLE ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CO) AS CR) AS P3) AS MG) SELE- NIUM. TOTAL (UG/L AS SE) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) NOV e 1982 09... 3.4 .130 JAN r 1983 18... 6.6 .170 1 <100 1 5 22 .3 <1 <1 MAR 17... 7.5 .200 MAY 09... 7.1 .260 AUG 23... 6.6 .010 1 100 1 <1 8 <.1 <1 <1 K = non-ideal count 43 RIO GRANDE DE ARECIBO BASIN 50025000 RIO GRANDE DE ARECIBO NEAR UTUADO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°18'11", long 66°41'59", 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, which is a diversion to Rio Guayan6s in the Rio Tallaboa basin. PERIOD OF RECORD.--Water years 1959-74, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND. FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, HARD- FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER AS DATE (C=S) (UMHOS) UNITS) MEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CACO3) NOV , 1982 03... 1415 59 289 8.0 23.0 6.5 7.4 95 17 3800 K1200 JAN , 1983 17... 1545 35 265 8.0 27.0 3.6 7.3 93 29 5800 K1500 98 MAR 18... 0910 38 258 8.0 23.0 2.9 8.1 96 17 4600 860 MAY 10... 1210 64 253 7.8 23.0 36 7.1 92 15 112000 27003 92 AUG 22... 1335 86 253 8.1 31.0 150 9.2 125 110 K150000 27000 92 HARD- NESS, UNGAR- 30NATE (MG/L DATE CACO3) CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM, DIS- SOLVED (MG/L AS NA) SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, AD- SIUM, LINITY SULFATE RIDE, RIDE, DIS- SORP- DIS- FIELD DIS- On- DIS- SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS AS K) CAC03) AS 504) AS CL) AS F) SI02) NOV , 1982 08... 87 JAN , 1983 17... 11 26 8.1 16 .7 2.4 87 20 11 .10 30 MAR 13... 52 MAY 10... 8 24 7.3 14 2.6 84 26 13 .10 26 AUG 22... 13 24 7.7 14 .7 2.0 79 21 15 .20 26 SOLIDS. SOLIDS, NITRO- SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GENtAM- CONSTI- DIS- AT 105 GEN, GEN. GEN, GEN, GEN, MCNIA + NITRO- NITRO- TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEN, DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) NOV , 1932 03... 24 .93 .073 1.0 .070 .33 .90 1.9 8.4 JAN , 1933 17... 166 15.7 <1 1.4 .100 1.5 .040 .26 .30 1.8 8.0 MAR 18... (1 1.2 .020 1.2 .030 .17 .20 1.4 6.2 MAY 10... 164 28.3 54 1.1 .060 1.2 .200 .50 .70 1.9 8.4 AUG 22... 157 36.5 212 1.2 .110 1.3 .163 .24 .40 1.7 7.5 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) CHRO* BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL SEDI- PHORUSt ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- MENT, TOTAL TOTAL ERABLE ERABLE ERASLE ERABLE ERASLE TOTAL ERABLE SUS- (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENDED DATE AS P) AS AS) AS 3A) AS CO) AS CR) AS P9) AS HG) AS SE) AS AG) (MG/L) NOV , 1982 08... .140 JAN , 1933 17... .190 1 100 1 5 13 .1 <1 <1 MAR 18... .120 MAY 10... .200 AUG 22... .090 1 200 1 <1 12 <.1 <1 <1 K = non-ideal count 96 10 RIO GRANDE DE ARECIBO BASIN 50026050 RIO CAONILLAS ABOVE LAGO CAONILLAS NEAR JAYUYA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°13'26", long 66°38'22", 300 ft (91.m) off Highway 531, 700 ft (213 m) upstream from Lago Caonillas, 3.3 mi (5.3 km) northwest of Jayuya plaza. DRAINAGE AREA.--40.4 sq mi (104.6 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, HARD- FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER AS DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CAC03) NOV , 1982 9... 1245 65 158 7.9 25.0 8.5 3.0 99 18 3000 K1500 JAN , 1983 18... 1310 35 208 8.5 21.0 1.2 3.9 103 31 470 200 76 MAR 17... 1045 53 207 8.0 24.0 34 8.1 100 11 K1700 6200 MAY 10... 0845 51 193 7.8 24.0 34 8.0 98 14 4000 540 70 AUG 23... 1205 32 215 8.2 27.5 6.7 10.6 138 20 K1000 K180 78 HARD- NESS, NONCAR- BONATE (MG/L DATE CAC03) CALCIUM DI S- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM, DIS- SOLVED (MG/L AS NA) SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, AO.... SIUM, LINITY SULFATE RIDE, RIDE, DIS- SORP- DIS- FIELD DIS- DIS- DIS- SOLVED TION SOLVED (MG/L SOLVEC SOLVED SOLVED (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS AS K) CAC03) AS SO4) AS CL) AS F) SI02) NOV , 1982 9... 51 JAN , 1983 18... 2 19 7.0 14 .7 1.6 74 15 10 .10 22 MAR 17... 64 MAY 10... 1 18 6.0 10 .5 1.6 69 19 11 <.10 24 AUG 23... S 21 6.3 11 .6 1.4 70 14 11 <.10 24 SOLIOS, SOLIDS, NITRO- SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GENpAM- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- NITRO- TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+403 AMMONIA ORGANIC ORGANIC GEN, GEN, DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) NOV , 1952 09... 15 <.010 .40 .010 .49 .50 .90 4.0 JAN , 1983 13... 133 12.6 1 .49 .010 .50 .020 .28 .30 .80 3.5 MAR 17... 4 1.1 .020 1.1 .080 .12 .20 1.3 5.8 MAY 10... 131 18.0 2 .47 .030 .50 .030 .37 .40 .90 4.0 AUG 23... 131 11.3 <1 .39 .010 .40 .320 .58 .60 1.0 4.4 CMR0- SEDI- 9ARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, MENT, PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL SEDI- OIS- PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- NEWT, CHARGE, TOTAL TOTAL ERABLE ERABLE ERA3LE ERABLE ERABLE TOTAL ERABLE SUS- SUS- (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENOEC PENDED DATE AS P) AS AS) AS 3A) AS CO) AS CR) AS PS) AS HG) AS SE) AS AG) (MG/L) (T/DAY) NOV r 1982 09... .070 JAN 1983 18... .170 1 <100 1 6 11 <.1 10 <1 MAR 17... .090 96 14 MAY 10... .090 AUG 23... .110 K = non-ideal count 44 45 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°40'02", 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. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 SPE- STREAM- CIFIC FLOW, CON- PH TUR- INSTAN- DUCT- (STAND- TEMPER- BID- TIME TANEOUS ANCE ARD ATURE ITY DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) NOV • 1982 08... 1150 136 203 7.4 26.0 3.2 JAN r 1983 17... 1450 187 204 7.3 25.0 3.1 MAR 18... 1210 23 212 7.6 25.0 2.7 MAY 10... 1400 E500 181 6.8 25.5 19 AUG 22... 1120 E700 222 7.3 27.5 13 OXYGEN. OXYGEN COLT- STREP- DIS- DEMAND. FORM. TOCOCCI SOLVED CHEM- FECAL, FECAL, OXYGEN. (PER- ICAL 0.7 KF AGAR DIS- CENT (HIGH UM-MF (COLS. SOLVED SATUR- LEVEL) (COLS./ PER (MG/L) ATION) (MG/L) 100 ML) 100 ML) 5.7 70 22 400 52 5.9 72 19 K36 160 7.1 87 12 80 70 5.1 63 16 270 310 3.4 43 16 370 550 HARD- MAGNE- SODIUM HARD- NESS., CALCIUM SIUMr SODIUM. AD- NESS NONCAR- DIS- DIS- DIS- SORP- (MG/L BONATE SOLVED SOLVED SOLVED TION AS (MG/L (MG/L (MG/L (MG/L RATIO DATE CAC03) CAC03) AS CA) AS MG) AS NA) POTAS- ALKA- SIUM, LINITY DIS- FIELD SOLVED (MG/L (MG/L AS AS K) CAC03) CHLO- FLUO- SULFATE RIDEr RIDE. DIS- DIS- DIS- SOLVED SOLVED SOLVED (MG/L (MG/L (MG/L AS SO4) AS CL) AS F) NOV • 1982 08... JAN • 1983 17... 73 MAR 18... MAY 10... 64 AUG 22... 76 69 1 19 6.1 12 .6 2.1 72 75 4 17 5.3 9.1 .5 2.2 60 1 20 6.4 11 .6 1.3 75 11 9.7 <.10 14 11 <.10 13 11 .10 SOLIDS, SOLIDS. NITRO- SILICA' SUM OF SOLIDS. RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN.AM- DIS- CONSTI- DIS- AT 105 GEN, GIN, GEN. GEN. GEN. MONIA + SOLVED TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC (MG/L On- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENOED (MG/L (MG/L (MG/L (MG/L ' (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) NITRO- GEN, TOTAL (MG/L AS N) NOV • 1982 08... JAN • 1983 17... MAR 18... MAY 10... AUG 22... 6 <.010 .20 .080 21 124 62.6 12 <.010 .60 .040 <1 .09 .010 .10 .090 17 112 15 .59 .010 .60 .020 18 126 <1 .040 <.10 .190 .92 1.00 1.2 .26 .30 .90 .01 .10 .20 .38 .40 1.0 .41 .60 CHRO- 3AR/UM, CADMIUM MIUM, LEAD, MERCURY NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL GEN/ PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL ERASLE ERASLE ERABLE ERABLE ERASLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CO) AS CR) AS P9) AS HG) NOV 1932 08... 5.3 .020 JAN t 1983 17... 4.0 .020 1 <100 1 3 11 .2 MAR 18... .89 .030 MAY 10... 4.4 .040 AUG 22... .050 1 100 4 <1 6 <.1 K = non-ideal count E . estimate SILVER, SELE- TOTAL NIUM, RECOV- TOTAL ERABLE (UG/L (UG/L AS SE) AS AG) <1 <1 <1 <1 46 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR LOCATION.--Lat 18°18'02", long 66°46'58", Hydrologic Unit 21010001, on downstream side of left abutment of bridge on Highway 111, 1.2 mi (1.9 km) uostream 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 sq mi (47.7 sq km). 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. Datum of gage is 938.32 ft (286.000 m) above mean sea level. Prior to Nov. 17, 1966, non-recording gage and Nov. 17, 1966 tc Sept. 30, 1978 recording gage, both at present site and datum 3.00 ft (0.914 m) higher. REMARKS.--Records fair. AVERAGE DISCHARGE.--23 years (1961-83), 48.4 cu ft/s (1.371 cu m/s), 35.72 in/yr (907 mm/yr), 35,070 acre-ft/yr (43.2 cu hm/yr); median of yearly mean discharges, 47 cu ft/s (1.33 cu m/s), 34,100 acre-ft/yr (42 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 8,950 cu ft/s (253 cu m/s) May 17, 1963, gage height, 13.29 ft (4.051 m) datum then in use, from floodmark, from rating curve extended above 500 cu ft/s (14.2 cu m/s) on basis of slope-area measurement of peak flow; minimum, 6.6 cu ft/s (0.187 cu m/s) June 12, 1977, gage height, 0.12 ft (0.037 m) datum then in use. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 3,000 cu ft/s (85.0 cu m/s) and maximum (*): Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Nov. 24 1715 *1,480 41.9 8.88 2.707 Minimum discharge, 8.0 cu ft/s (0.226 cu m/s) Apr. 9, 10. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 27 28 37 39 19 15 9.8 29 27 19 22 22 2 29 26 35 34 19 14 9.7 22 25 22 21 21 3 26 26 34 31 18 15 9.3 21 59 16 58 21 4 25 25 35 30 18 14 9.5 45 47 19 72 20 5 25 25 32 30 19 24 9.6 37 31 21 33 22 6 29 24 31 29 18 17 10 56 27 19 23 86 7 80 24 30 29 17 14 9.5 60 24 16 20 40 3 52 24 30 24 16 14 9.1 57 24 15 25 24 9 36 45 33 27 17 14 8.6 39 25 53 33 20 10 32 57 30 25 17 13 8.3 36 23 34 55 20 11 31 53 29 25 16 13 8.8 66 21 60 35 39 12 30 52 29 25 16 20 8.7 43 21 31 24 28 13 29 54 50 25 16 18 14 76 20 21 25 21 14 41 36 35 24 16 14 15 51 20 19 58 19 15 46 41 53 24 16 13 48 39 19 18 47 19 16 32 52 41 22 16 13 32 33 19 42 34 18 17 33 92 35 22 16 12 13 64 19 57 79 59 13 71 89 32 21 16 12 12 92 24 42 48 45 19 75 55 30 21 16 12 12 57 19 25 33 29 20 52 44 39 24 16 12 15 33 18 23 29 23 21 38 38 39 21 25 11 118 35 18 21 41 21 22 33 S6 34 21 17 11 28 70 17 20 32 50 23 31 34 32 21 16 11 22 54 16 29 27 60 24 30 137 31 23 16 11 20 74 16 25 25 36 25 29 61 30 20 15 10 18 53 15 19 3C 27 26 29 47 30 21 15 10 17 56 16 19 34 24 27 28 59 41 21 15 11 16 39 16 19 39 22 28 28 53 44 23 15 10 16 33 16 20 30 21 29 29 42 67 20 --- 10 43 31 15 21 25 21 30 34 39 64 1? 10 35 31 17 21 24 20 31 29 --- 46 19 9.9 --- 21 --- 22 23 --- TOTAL 1138 1418 1157 751 472 407.9 634.9 1465 674 803 1104 393 MEAN 36.7 47.3 37.3 24.5 16.9 13.2 20.2 47.3 22.5 26.1 35.6 29.9 MAX 10 137 67 39 25 24 118 92 59 60 79 36 MIN 25 24 29 19 15 9.9 8.3 21 15 15 20 13 CFSM 2.00 2.57 2.03 1.33 .92 .72 1.10 2.57 1.22 1.42 1.94 1.63 IN. 2.30 2.87 2.34 1.53 .95 .82 1.22 2.96 1.36 1.63 2.23 1.82 AC-FT 2260 2810 2290 1500 936 809 1200 2910 1340 1600 2190 1780 CAL YR 1982 TOTAL 11912.0 MEAN 32.6 MAX 431 MIN 14 CFSM 1.77 IN 24.03 AC-FT 23630 WTR YR 1983 TOTAL 10904.8 MEAN 29.9 MAX 137 MIN 8.3 CFSM 1.63 IN 22.05 AC-FT 21630 47 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 of 10 years. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONS: Maximum daily mean, 20,400 mg/L November 27, 1968; minimum daily mean, 0.0 mg/L during many years. SEDIMENT LOADS: Maximum daily, 110,000 tons (100,000 tonnes) November 27, 1968, minimum daily, 0.0 ton (0.0 tonne) during many years. EXTREMES FOR CURRENT YEAR.-- SEDIMENT CONCENTRATIONS: Maximum daily mean, 1210 mg/L Apr. 21, 1983; minimum daily mean, 0.0 mg/L several days during 1983. SEDIMENT LOADS: Maximum daily, 1,470 tons (1,330 tonnes) Nov. 24, 1982; minimum daily, 0.0 ton (0.0 tonne) several days during 1983. WATER-QUALITY DATA, WATER YEARS OCTOBER 1980 TO SEPTEMBER 1982 OXYGEN. OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL. FECAL, HARD- FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER AS DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CAC03) NOV r 1982 15... 1315 29 160 7.8 24.0 14 8.3 103 <10 600 730 DEC 15... 1215 78 177 7.7 21.0 9.3 108 36 K190 40000 56 JAN , 1983 26... 1120 22 173 8.1 22.0 1.9 8.7 103 <10 K100 K150 62 FEB 16... 1225 17 172 8.3 21.5 2.1 9.0 105 2500 K160 63 MAR 28... 1320 10 170 8.7 24.5 <1.0 3.4 104 15 K130 280 MAY 11... 1020 37 136 7.4 23.0 270 8.3 100 61 K8300 47000 49 AUG 29... 1205 26 177 8.3 25.0 5.0 9.0 113 16 340 440 67 SOLIDS, HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, RESIDUE NESS, CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE. RIDE. DIS- AT 180 NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- GIS- 015- SOLVED DEG. C BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L On- (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS SOLVED DATE CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS 504) AS CL) AS F) SI02) (MG/L) NOV r 1982 15... 52 DEC 15... 0 16 3.9 7.7 .5 2.7 56 8.0 7.9 .10 18 JAN • 1983 26... 3 15 6.0 8.8 .5 1.5 59 12 7.6 <.10 27 FEB 16... 7 16 5.7 8.1 .5 1.4 57 13 7.9 <.10 25 110 MAR 28... 61 MAY 11... 3 13 4.0 6.9 .4 2.0 46 9.0 7.9 <.10 19 AUG 29... 8 17 6.0 8.1 .4 1.6 59 12 7.8 <.10 26 SOLIDS, SOLIDS. NITRO- NITRO- SUM OF SOLIDS. RESIDUE NITRO- NITRO- NITRO- GEN, NITRO- NITRO'''. GEN,AM- CONSTI- DIS- AT 105 GEN, GEN. GEN. NO2+NO3 GEN. GEN. MONT!. + NITRO"' TUENTS, SOLVED DEG. C. NITRATE NITRITE NO2+N O3 DIS- AMMONIA ORGANIC OKtiANIC GEN, DIS- (TONS SUS- TOTAL TOTAL TOTAL SOLVED TOTAL TOTAL TOTAL TOTAL SOLVED PER FENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV . 1982 15... 15 .69 .010 .70 <.010 .30 1.0 DEC 15... 98 20.6 .85 JAN 0 1983 26... 113 6.7 1 <.010 .70 .020 <.10 FEB 16... 111 5.0 <.010 .60 .04C .46 .50 1.1 MAR 28... 6 .29 .010 .30 <.010 .30 .60 MAY 11... 89 8.8 279 .91 .290 1.2 .600 .00 .50 1.7 AUG 29... 114 8.0 9 <.010 .50 <.010 .30 .80 K = non-ideal count 48 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 PHOS- BARIUM. PHORUS, ARSENIC BARIUM, SUS- CADMIUM NITRO- PHOS- ORTHO. SUS- ARSENIC TOTAL PENDED BARIUM, TOTAL CADMIUM GEN. PHORUS, DIS- ARSENIC PENDED On- RECOV- RECOV- CIS- RECOV- DIS- TOTAL TOTAL SOLVED TOTAL TOTAL SOLVED ERABLE ERABLE SOLVED ERABLE SOLVED (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UGIL (UG/L (UG/L (UG/L DATE AS NO3) NOV , 1982 AS P) AS P) AS AS) AS AS) AS AS) AS BA) AS BA) AS BA) AS CD) AS CD) 15... 4.4 .090 DEC 15... <.010 JAN , 1983 26... .010 1 100 5 FEB 16... 4.9 .030 1 0 1 100 70 34 <1 1 MAR 28... 2.7 .030 MAY 11... 7.5 .250 AUG 29... 3.5 .020 1 <100 1 CHRO.. CHRO- CHRO- COBALT, COPPER, COPPER,' MIUM. MIUM. CHRO- MIUM, COBALT, SUS- COPPER, SUS- RECOV. TOTAL SUS- MIUM, RECOV. TOTAL PENDED COBALT, TOTAL PENDED COPPER., FM BOT- RECOV- FENDED On- FM BOT- RECOV- RECOV- DIS- RECOV- RECOV- DIS- TOM MA... ERASLE RECOV. SOLVED TOM MA- ERASLE ERABLE SOLVED ERABLE ERABLE SOLVED TERIAL (UG/L (UG/L (UG/L TERIAL (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/G DATE AS CR) AS CR) AS CR) (UG/G) AS CO) AS CO) AS CO) AS CU) AS CU) AS CU) AS CU) NOV r 1982 15... 3 19 DEC 15... JAN • 1983 26... <1 FEB 16... 20 0 20 1 0 1 8 4 4 MAR 28... MAY 11... AUG 29... <1 IRON., MANGA- MANGA- MERCURY IRON., TOTAL RECOV- SUS- PENDED RECOV- IRON, DIS- LEAD, TOTAL RECOV- LEAD, On- NESE, TOTAL RECOV- NESE. SUS- PENDED MANGA- NESE, DIS- MERCURY TOTAL RECOV- SUS- PENDED RECOV- MERCURY DIS- ERABLE ERABLE SOLVED ERABLE SOLVED ERABLE RECOV. SOLVED ERABLE ERABLE SOLVED (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS FE) AS FE) AS FE) AS PB) AS PB) AS MN) AS MN) AS MN) AS HG) AS HG) AS HG) NOV 1982 15... DEC 15... 68 17 JAN 1983 26... <1 .2 FEB 16... 490 480 14 <1 <1 30 20 7 .5 .3 .2 MAR 28... MAY 11... AUG 29... 4 <.1 NICKEL, NICKEL, NICKEL, SUS- RECOV. SELE- SILVER, ZINC, TOTAL PENDED NICKEL, FM BOT- SELE- NIUM, TOTAL SILVER, TOTAL ZINC. RECOV- RECOV- DIS- TOM MA- NIUM, DIS- RECOV- DIS- RECOV- On- ERABLE ERABLE SOLVED TERIAL TOTAL SOLVED ERABLE SOLVED ERABLE SOLVED (UG/L (UG/L (UG/L (UG/G (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NI) AS NI) AS NI) AS NI) AS SE) AS SE) AS AG) AS AG) AS ZN) AS ZN) RECOV. FM BOT- TOM MA- TERIAL (UG/G AS ZN) NOV , 1982 15... <10 DEC 15... JAN 1983 26... <1 2 FEB 16... 77 72 5 <1 <1 <1 MAR 28... MAY 11... AUG 29... <1 <1 <1 20 <3 24 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 4 9 STREAMFLOWr 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) OCT' 04 1333 25 170 25.0 JUL, 12 1253 28 131 24.5 APR, 12 1200 8.5 207 24.5 SEP. 07 1022 214 186 26.0 JUN. 01 1315 25 179 -- CHLOR- DI- PCB. *LORIN, DANEr DOD, DDE. DDT. AZINON, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN r 1983 03... 1240 (.10 <.01 (.10 <.01 <.01 <.01 <.01 HEPTA- METH- DI- ENDO- HEPTA- CHLOR MALA- OXY- ELDRIN SULFAN, ENDRIN. ETHION. CHLOR. EPDXIDE LINDANE THION. CHLOR, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN . 1983 03... <.01 <.10 <.01 <.01 <.01 <.01 <.01 <.01 <.01 NAPH- THA- METHYL METHYL LENES. PARA- TRI- PARA- POLY- PER- TOX- TOTAL THION, THION, MIREX. THION. CHLOR. THANE APHENE, TRI- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL THION DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN r 1983 03... <.01 <.01 <.01 <.01 (.10 <.10 <1 (.01 SED. SED. SEQ. SEQ. SUSP. SUSP. SUSP. SUSP. STREAM- SEDI- FALL FALL FALL FALL FLOW, MENT, DIAM. DIAM. DIAM. DIAM. INSTAN- SUS- % FINER X FINER % FINER X FINER TIME TANEOUS FENDED THAN THAN THAN THAN DATE (CFS) (MG/L) .002 MM .004 MM .008 MM .016 MM AUG . 1983 10... 1750 E2860 3500 1 4 14 26 10... 1805 E3350 3960 3 6 17 31 10... 1820 E2780 3320 2 5 12 32 10... 1830 E2110 2660 2 3 7 24 SED. SEO. SED. SED. SEQ. SEO. SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. FALL SIEVE SIEVE SIEVE SIEVE SIEVE DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. % FINER % FINER % FINER B FINER % FINER % FINER THAN THAN THAN THAN THAN THAN DATE .031 MM .062 MM .125 MM .250 MM .500 MM 1.00 MM AUG 10... 44 82 83 94 97 99 10... 53 34 92 96 98 99 10... 54 84 91 94 97 99 10... 43 79 90 93 95 99 SED. SED. SEQ. SED. SED. SEQ. BED SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. MAT. STREAM- FALL FALL FALL FALL FALL FALL FALL FLOW. D1AM. DIAM. DIAM. DIAM. DIAN. DIAM. QIAM. INSTAN- X FINER % FINER % FINER % FINER % FINER % FINER % FINER TIME TANEOUS THAN THAN THAN THAN THAN THAN THAN DATE (CFS) 002 MM .004 MM .003 MM .016 MM .031 MM .062 MM .004 MM DEC . 1982 15... 1215 78 0 1 1 1 2 2 1 JAN , 1983 26... 1120 22 0 0 0 1 1 1 0 FEB 16... 1225 17 0 0 0 0 1 1 0 BED BED BED BED BED BED BED BED MAT. MAT. MAT. MAT. MAT. MAT. MAT. MAT. FALL SIEVE SIEVE SIEVE SIEVE SIEVE SIEVE SIEVE DIAM. DIAM. DIAM. DIAM. QIAM. DIAM. DIAM. DIAM. % FINER % FINER X FINER I FINER X FINER % FINER % FINER % FINER THAN THAN THAN THAN THAN THAN THAN THAN DATE .062 MM .062 MM .125 MM .250 MM .500 MM 1.00 MM 2.00 MM 4.00 MM DEC 15... 2 2 3 5 22 54 74 89 JAN 26... 1 1 1 3 7 25 52 68 FEB 16... 1 1 1 3 13 38 61 72 E = estimate 50 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO. PR--Continued WATER QUALITY DATA. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 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/I) (TONS/DAY) OCTOBER NOVEMBER DECEMBER 1 27 10 .73 28 11 .83 37 211 22 2 29 99 8.7 26 19 1.3 35 164 15 3 26 64 4.6 26 69 4.8 34 152 14 4 25 24 1.6 25 9 .61 35 164 15 5 25 5 .34 25 36 2.4 32 123 11 6 29 104 13 24 22 1.4 31 7 .59 7 80 793 622 24 14 .91 30 96 7.8 8 52 590 96 24 25 1.6 30 96 7.8 9 36 89 8.7 45 268 79 33 151 16 10 32 17 1.5 57 457 142 30 115 9.3 11 31 10 .84 53 329 59 29 82 6.4 12 30 12 .97 52 333 70 29 82 6.4 13 29 22 1.7 54 372 69 50 320 133 14 41 235 63 36 135 20 35 226 24 15 46 359 51 41 236 47 53 348 65 16 32 21 1.8 52 416 77 41 218 25 17 33 133 13 92 845 414 35 164 15 18 71 533 583 89 932 309 32 123 11 19 75 911 263 55 549 86 30 96 7.8 20 52 392 58 44 326 40 38 203 24 21 38 23 2.4 38 207 21 39 222 23 22 33 43 3.8 36 112 11 34 152 14 23 31 20 1.7 34 152 14 32 123 11 24 30 8 .65 137 1170 1470 31 110 9.2 25 29 12 .94 61 648 116 30 96 7.8 26 29 3 .23 47 360 51 30 96 7.8 27 28 8 .60 59 470 85 41 262 37 28 28 14 1.1 53 432 62 44 300 36 29 28 148 11 42 145 16 67 542 146 30 34 15 1.4 39 231 25 64 582 125 31 29 11 .86 --- --- --- 46 336 43 TOTAL 1138 1818.16 1418 3296.85 1157 895.89 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 39 222 23 19 5 .26 15 0 .00 2 34 152 14 19 5 .26 14 0 .00 3 31 13 1.1 18 3 .15 15 0 .00 4 30 96 7.3 18 3 .15 14 0 .00 5 30 96 7.8 19 5 .26 24 123 28 6 29 82 6.4 18 3 .15 17 3 .15 7 29 82 6.4 17 30 1.4 14 45 1.7 8 28 69 5.2 16 1 .04 14 0 .00 9 27 58 4.2 17 2 .09 14 0 .00 10 25 60 4.1 17 2 .09 13 0 .00 11 25 36 2.4 16 1 .04 13 0 .00 12 25 36 2.4 16 1 .04 20 50 5.3 13 25 36 2.4 16 1 .04 18 10 .65 14 24 27 1.7 16 56 2.4 14 41 1.5 15 24 27 1.7 16 1 .04 13 0 .00 16 22 16 .95 16 1 .04 13 0 .00 17 22 60 3.6 16 1 .04 12 0 .00 18 21 11 .62 16 1 .04 12 0 .00 19 21 11 .62 16 1 .04 12 0 .00 20 24 27 1.7 16 1 .04 12 0 .00 21 21 11 .62 25 37 2.5 11 65 1.9 22 21 11 .62 17 2 .09 11 0 .00 23 21 11 .62 16 1 .04 11 0 .00 24 20 104 5.6 16 1 .04 11 0 .00 25 20 8 .43 15 0 .00 10 0 .00 26 21 11 .62 15 0 .00 10 0 .00 27 21 11 .62 15 0 .00 11 0 .00 28 20 8 .43 15 0 .00 10 37 1.0 29 20 8 .43 --- 10 0 .00 30 19 5 .26 10 0 .00 31 19 39 2.0 9.9 0 .00 TOTAL 758 110.34 472 8.28 407.9 40.20 51 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR-Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 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 9.8 0 .00 29 110 16 27 58 4.2 2 9.7 0 .00 22 16 1.0 25 36 2.4 3 9.3 0 .00 21 16 1.0 59 533 372 4 9.5 27 .69 45 367 132 47 346 55 5 9.6 0 .00 37 200 25 31 110 9.2 6 10 0 .00 56 462 206 27 58 4.2 7 9.5 0 .00 60 552 164 24 27 1.7 8 9.1 0 .00 57 494 115 24 27 1.7 9 8.6 0 .00 39 226 26 25 36 2.4 10 8.3 0 .00 36 176 40 23 20 1.2 11 8.8 57 1.4 66 587 222 21 11 .62 12 8.7 0 .00 43 285 35 21 11 .62 13 14 30 2.3 76 730 228 20 8 .43 14 15 3 .16 51 406 56 20 8 .43 15 48 434 226 39 226 24 19 5 .26 16 32 161 28 33 137 12 19 5 .26 17 13 0 .00 64 526 209 19 5 .26 18 12 34 1.1 92 959 496 24 27 1.7 19 12 0 .00 57 498 84 19 5 .26 20 15 88 30 38 219 23 18 3 .15 21 118 1210 642 35 180 18 18 3 .15 22 28 69 5.5 70 651 268 17 2 .09 23 22 16 .95 54 445 68 16 1 .04 24 20 8 .43 74 701 241 16 1 .04 25 18 27 1.3 53 441 66 15 0 .00 26 17 2 .09 56 469 108 16 1 .04 27 16 1 .04 39 227 25 16 1 .04 28 16 1 .04 33 137 12 16 1 .04 29 43 385 181 31 110 9.2 15 0 .00 30 35 182 26 31 110 9.2 17 2 .09 31 --- --- --- 28 69 5.2 --- --- TOTAL 604.9 1147.50 1465 2944.6 674 459.52 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) (M0/1) (TONS/DAY) JULY AUGUST SEPTEMBER 1 19 30 4.0 22 19 1.4 22 16 .95 2 22 37 3.3 21 14 .84 21 11 .62 3 16 1 .04 58 454 291 21 11 .62 4 19 36 3.7 72 643 250 20 8 .43 5 21 17 1.1 33 150 17 22 16 .95 6 19 8 .44 23 20 1.2 86 975 1330 7 16 1 .04 20 8 .43 40 249 33 8 15 0 .00 25 121 28 24 27 1.8 9 53 440 278 33 150 20 20 8 .43 10 34 167 24 55 540 355 20 8 .43 11 60 514 224 35 169 19 39 255 72 12 31 112 11 24 27 1.7 28 71 6.3 13 21 11 .62 25 49 4.4 21 11 .62 14 19 5 .26 58 544 284 19 5 .26 15 18 3 .15 47 353 55 19 5 .26 16 42 310 109 34 163 17 18 3 .15 17 57 522 184 79 725 299 59 479 253 18 42 270 39 48 361 51 45 313 56 19 25 36 2.4 33 128 11 29 86 7.5 20 23 20 1.2 29 83 7.0 23 20 1.2 21 21 11 .62 41 255 32 21 11 .62 22 20 8 .43 32 124 11 50 433 197 23 29 219 53 27 58 4.2 60 484 197 24 25 58 5.1 25 36 2.4 36 180 19 25 19 5 .26 30 116 22 27 58 4.2 26 19 5 .26 34 152 16 24 27 1.7 27 19 5 .26 39 235 49 22 16 .95 28 20 8 .43 30 90 7.6 21 11 .62 29 21 11 .62 25 36 2.4 21 11 .62 30 21 11 .62 24 27 1.7 20 8 .43 31 22 16 .95 23 20 1.2 --- --- --- TOTAL 808 948.80 1104 1863.47 898 2183.66 YEAR 10904.3 15722.27 52 RIO GRANDE DE ARECIBO BASIN 50028400 RIO TANAMA AT CHARCO HONDO, PR LOCATION.--Lat 18°24'52", long 66°42'52", on right bank of abandoned power house at Charco Hondo, 1.5 mi (2.4 km) upstream from mouth, and 4 mi (6 km) south of Arecibo. DRAINAGE AREA.--57.6 sq mi (149.2 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--April 1969 to June 1971, October 1981 to current year. GAGE.--Water-stage recorder. Altitude of gage is 60 ft (18 m), from topographic map. REMARKS.--Records fair. Diversion 0.8 mi (1.3 km) upstream from municipal supply of Arecibo. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 4,120 cu ft/s (117 cu m/s) Apr. 21, 1969, gage height, 12.22 ft (3.725 m) from floodmark, from rating curve extended above 1,000 cu ft/s (28 cu m/s); minimum, 30 cu ft/s (0.850 cu m/s) Apr. 11-13, 1983. EXTREMES FOR WATER YEARS 1982-83.--Peak discharges above base of 1,000 cu ft/s (28.3 cu m/s) and maximums (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Oct. 25, 1981 1800 1,910 54.1 9.95 3.033 Nov. 9, 1981 1300 3,420 96.8 11.88 3.621 Nov. 3 1830 1,460 41.3 9.19 2.801 Dic. 14 0900 2,040 57.8 10.14 3.091 Nov. 5 1900 1,560 44.2 9.37 2.856 Sept. 13, 1982 0400 *3,970 112 12.45 3.795 Nov. 8 1830 1,840 52.1 9.83 2.996 Nov. 24 2030 *1,360 38.5 9.00 2.743 Nov. 9 0230 2,680 75.9 11.03 3.362 Minimum discharges, 46 cu ft/s (1.303 cu m/s) Apr. 24, 25, May 2, 3, 1982; 30 cu ft/s (0.850 cu m/s) Apr. 11-13, 1983. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1981 TC SEPTEMBER 1982 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 72 231 103 123 75 57 52 51 113 51 58 100 2 78 204 100 118 76 56 52 46 101 50 68 121 3 72 369 96 113 39 56 52 126 180 49 59 71 4 71 344 94 109 75 55 58 123 130 50 66 63 5 71 430 92 103 86 54 131 163 110 75 118 60 6 79 449 88 97 90 54 70 180 100 174 60 65 7 160 253 85 94 80 54 58 190 110 155 56 114 8 120 346 34 93 75 54 53 180 120 76 85 66 9 107 1270 82 92 70 54 52 120 101 61 112 60 10 91 530 30 89 67 54 53 110 85 104 117 71 11 155 360 175 86 67 53 72 200 76 59 146 85 12 155 264 166 86 64 54 54 130 65 53 78 123 13 119 186 490 82 67 53 53 240 60 53 89 336 14 97 168 1160 11 67 53 52 160 58 67 77 253 15 90 152 630 80 66 54 52 120 56 89 109 136 16 98 133 444 73 66 55 93 100 55 67 71 100 17 155 121 332 77 67 54 71 200 54 92 63 115 18 155 131 261 76 66 54 57 120 53 62 67 192 19 111 221 237 76 62 54 55 81 52 80 62 205 20 204 178 210 76 61 54 52 123 51 208 58 138 21 254 117 200 76 61 54 52 173 50 245 56 109 22 164 113 194 75 61 53 50 100 50 94 55 90 23 184 114 183 74 60 51 51 138 49 86 75 82 24 260 162 178 74 58 51 46 122 49 72 61 77 25 433 112 172 74 56 52 50 126 49 72 69 74 26 306 146 167 74 56 52 50 96 48 84 85 67 27 228 303 156 105 56 52 49 116 48 71 60 64 28 253 152 143 179 57 51 48 220 48 62 70 61 29 243 117 136 85 --- 51 52 194 51 61 144 60 30 234 109 128 90 51 54 153 53 62 33 81 31 260 --- 126 80 59 --- 130 --- 59 64 --- TOTAL 5129 7789 6792 2315 1901 1663 1744 4336 2225 2643 2441 3739 MEAN 165 260 219 90.9 67.9 53.6 58.1 140 74.2 85.3 78.7 125 MAX 433 1270 1160 179 90 59 131 240 130 245 146 336 MIN 71 109 80 74 56 51 46 46 48 49 55 60 CFSM 2.87 4.51 3.30 1.58 1.18 .93 1.31 2.43 1.29 1.43 1.37 2.17 IN. 3.31 5.03 4.39 1.82 1.23 1.07 1.13 2.80 1.44 1.71 1.58 2.41 AC-FT 10170 15450 13470 5580 3770 3300 3460 8600 4410 5240 4840 7420 WTR YR 1982 TOTAL 43217 MEAN 113 MAX 1270 MIN 46 CFSM 2.05 IN 27.91 AC-FT 85720 53 RIO GRIME DE ARECIBO BASIN 50028400 RIO TANAMA AT CHARCO HONDO, PR--Continued DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 71 53 95 100 51 40 33 63 69 39 43 45 2 58 51 90 90 51 39 32 91 52 45 44 45 3 76 50 35 85 50 35 31 47 68 39 41 44 4 74 50 86 81 49 41 31 52 117 39 122 44 5 93 49 31 76 48 43 31 118 70 49 92 43 6 76 43 72 76 49 65 32 137 94 43 49 81 7 92 41 70 72 49 42 32 193 38 39 46 112 3 125 43 69 67 48 40 31 164 64 38 45 60 9 85 82 67 64 48 39 31 161 61 40 64 50 10 60 169 71 62 48 33 31 87 60 109 62 47 11 58 134 64 61 48 33 30 1C3 62 76 90 50 12 58 145 66 60 48 37 30 181 60 83 59 76 13 57 136 62 57 48 47 34 272 52 50 50 51 14 56 88 100 55 47 39 50 376 50 44 65 46 15 81 76 75 58 47 38 40 173 48 43 103 45 16 80 190 110 56 47 36 116 116 46 52 60 45 17 59 128 90 55 47 36 48 177 46 81 156 66 18 58 185 75 55 47 35 40 219 48 100 156 106 19 150 183 70 55 46 34 43 185 46 54 69 87 20 104 133 70 55 46 35 45 104 45 48 57 55 21 74 96 35 52 53 35 241 86 44 45 62 52 22 64 88 35 51 49 34 70 138 43 44 68 68 23 62 81 75 51 45 34 47 163 41 42 53 86 24 60 217 70 51 44 34 42 143 40 67 50 77 25 59 330 70 51 43 33 38 157 40 45 48 65 26 58 135 70 50 42 34 36 166 38 41 59 63 27 62 110 70 50 41 33 34 204 38 40 62 53 23 57 135 90 51 40 33 33 123 38 40 76 63 29 56 120 95 51 --- 33 41 93 38 41 52 55 30 56 110 135 52 32 114 90 38 43 47 47 31 56 --- 110 52 33 --- 94 --- 44 48 --- TOTAL 2235 3473 2523 1902 1319 1163 1437 4486 1654 1608 2098 1323 MEAN 72.1 116 81.4 61.4 47.1 37.7 49.6 145 55.1 51.9 67.7 60.9 MAX 150 330 135 100 53 65 241 376 117 109 156 112 MIN 56 48 62 50 40 32 30 47 38 33 41 43 CFSM 1.25 2.01 1.41 1.07 .82 .66 .86 2.52 .96 .90 1.18 1.06 IN. 1.44 2.25 1.63 1.23 .85 .75 .96 2.90 1.07 1.04 1.35 1.18 AC-FT 4430 6900 5000 3770 2620 2320 2950 8900 3230 3190 4160 3630 CAL YR 1982 TOTAL 31743 MEAN 87.0 MAX 836 MIN 46 CFSM 1.51 IN 20.50 AC-FT 62960 WTR YR 1983 TOTAL 25786 MEAN 70.6 MAX 376 MIN 30 CFSM 1.23 IN 16.65 AC-FT 51150 WATER-2UALITY RECORDS PERIOD OF RECORD.--MARCH TO SEPTEMBER 1983 WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEM3ER 1913 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- OATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS OUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) MAR, 14 1322 39 311 24.0 JUL, 13 1003 49 265 24.0 APR, 05 1320 31 354 23.0 AUG, 09 1407 65 248 25.5 MAY, 16 1532 140 303 24.5 SEP, 01 1503 46 259 27.0 JUN, 02 1420 62 276 -- 54 RIO GRANDE DE ARECIBO BASIN 50029000 RIO GRANDE DE ARECIBO AT CENTRAL CAMBALACHE, PR 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, 13.9 mi (22.4 km) downstream from Dos Bocas Reservoir, 1.9 mi (3.1 km) downstream from Rio Tanamg, and 1.6 mi (2.6 km) southeast of Arecibo. DRAINAGE AREA. --200 sq mi (520 sq km), approximately. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1963 to January 1965 (monthly measurements only), February 1965 to April 1969 (occasional measurements only), May 1969 to September 1983 (discontinued). GAGE.--Water-stage recorder. Datum of gage is 3.73 ft (1.137 m) above mean sea level. REMARKS.--Records very poor. Flow regulated by Lago Dos Bocas dam, 13.9 mi (22.4 km) upstream. AVERAGE DISCHARGE.--14 years (1970-83), 510 cu ft/s (14.44 cu m/s), 369,500 acre-ft/yr (456 cu hm/yr); median of yearly mean discharges, 504 cu ft/s (14.27 cu m/s), 365,000 acre-ft/yr (450 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 26,100 cu ft/s (739 cu m/s) Aug. 31, 1979, gage height, 13.74 ft (4.188 m) from rating curve extended above 6,000 cu ft/s (170 cu m/s); minimum, 50 cu ft/s (1.416 cu m/s) Feb. 26, 1974, gage height, 4.25 ft (1.295 m). EXTREMES OUTSIDE PERIOD OF RECORD.--Approximate discharges and elevations above mean sea level of major floods at valley cross sections along Expressway PR-22 about 1.0 mi (1.6 km) above gage site are as follows: Aug. 8, 1899, 195,000 cu ft/s (5,520 cu m/s), gage height, 24.4 ft (7.44 m); Sept. 13, 1928, 105,000 cu ft/s (2,970 cu m/s), gage height, 21.6 ft (6.58 m); Oct. 13, 1954, 76,000 cu ft/s (2,150 cu m/s), gage height, 19.1 ft (5.82 m); and Nov. 26, 1968, 21,000 cu ft/s (595 cu m/s) gage height, 16.6 ft (5.06 m). EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 4,350 cu ft/s (123 cu m/s) and maximum (*): Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Apr. 21 1345 8,680 246 11.66 3.554 Minimum daily discharge , 63 cu ft/s (1.784 cu m/s) Mar. 3. DISCHARGE, IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 1020 465 283 150 850 114 138 320 400 210 267 240 2 319 277 270 700 169 90 270 500 183 133 137 193 3 279 403 169 110 99 63 208 250 560 135 103 36 4 222 289 453 300 85 191 252 400 532 144 169 97 5 598 184 222 300 156 151 124 1100 284 728 610 290 6 564 377 586 350 127 136 104 1200 45E 678 220 397 7 514 254 988 300 266 137 227 140 420 721 121 526 8 318 386 686 180 328 133 398 200 419 677 390 123 9 162 555 730 250 204 193 521 800 447 234 501 166 10 314 425 476 900 260 260 223 1200 494 590 541 129 11 333 602 553 1100 279 192 131 600 470 185 310 119 12 137 803 252 250 243 271 254 550 306 139 295 131 13 479 1930 374 550 133 642 143 2000 483 117 415 410 14 423 852 495 170 107 524 313 1300 460 143 314 753 15 305 952 265 110 173 162 314 1200 566 126 350 170 16 150 2110 489 95 233 153 323 400 292 100 291 369 17 176 '334 360 600 244 247 265 400 427 274 476 892 13 400 952 268 1200 177 252 380 1000 599 377 441 474 19 828 1110 114 1100 188 281 292 2000 480 276 217 673 20 766 453 330 400 234 627 229 2000 690 216 132 372 21 186 314 629 1200 322 346 7000 1100 161 415 250 777 22 578 827 449 450 130 196 2000 1200 264 410 574 297 23 417 717 336 400 165 376 1600 2500 120 137 309 178 24 358 951 150 1000 320 154 1300 1300 508 211 158 153 25 474 2410 100 150 174 213 600 1700 251 104 150 128 26 241 1430 120 130 222 154 200 1300 268 691 95 183 27 304 810 2000 220 133 186 120 2000 238 155 201 468 28 213 1263 1500 350 166 113 160 1000 401 242 270 330 29 535 1050 1000 200 --- 281 830 250 426 193 478 516 30 510 291 1800 250 361 300 1000 397 149 374 161 31 411 --- 600 600 165 --- 900 --- 102 477 --- TOTAL 12509 24283 17047 15065 6187 7379 19239 32310 12054 9122 9636 10356 MEAN 404 309 550 486 221 233 641 1042 402 294 311 362 MAX 1020 2410 2000 1200 850 642 7000 2500 690 723 610 892 MIN 137 184 100 95 35 63 104 140 120 100 95 86 AC-FT 24810 48170 33810 29380 12270 14640 35160 64090 23910 18090 19110 21530 CAL YR 1982 TOTAL 166790 MEAN 457 MAX 3200 MIN 60 AC-FT 330800 WTR YR 1983 TOTAL 175637 MEAN 481 MAX 7000 MIN 63 AC-FT 343500 RIO GRANDE DE ARECIBO BASIN 50029000 RIO GRANDE DE ARECIBO AT CENTRAL CAMBALACHE, PR--Continued 55 WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1963-66, 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN. OXYGEN COLT- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 11... 1300 E1460 257 7.1 25.5 49 7.1 87 18 22000 3500 FEB p 1983 1... 1400 147 247 7.7 24.0 4.3 10.3 122 12 2000 K140 MAR 25... 1245 86 290 8.0 23.0 <1.0 13.0 166 47 K50 K140 MAY 2... 1115 E300 245 7.4 25.0 12 7.6 92 12 K1700 3000 JUN 16... 1115 E235 253 8.2 27.0 AUG 12... 1125 118 255 7.9 27.0 65 7.6 96 27 2400 3200 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM, SODIUM, AD- SIUMp LINITY SULFATE RIDE. RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1932 11... 92 FEB , 1933 1... 110 4 36 5.9 9.7 .4 1.4 110 10 9.8 <A0 MAR 25... 120 MAY 2... 110 11 35 4.7 8.3 .4 1.3 96 14 10 <.10 JUN 16... 110 0 36 5.5 9.2 .4 1.6 120 10 9.8 .10 AUG 12... 110 0 36 5.3 8.3 .4 1.6 112 9.7 9.4 .10 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- CIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 11... 122 .49 .010 .50 .020 .63 .70 1.2 FES , 1933 1... 17 156 61.3 9 .49 .010 .50 .020 <.10 MAR 25... 4 .29 .010 .30 <.010 <.10 MAY 2... 14 145 16 .88 .020 .90 .060 .24 .30 1.2 JUN 16... 17 161 AUG 12... 14 152 48.3 60 .57 .030 .60 .080 .32 .40 1.0 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV r 1982 11... 5.3 .110 FEB , 1983 01,.. .040 1 100 1 3 1 .3 <1 3 MAR 25... .010 MAY 02... 5.3 .080 JUN 16... AUG 12... 4.4 .040 2 100 1 <1 9 <.1 <1 <1 STREAMFLOWr 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) OCT, 15 1010 222 272 25.5 JUL, 12 0955 219 257 26.5 APR, 07 1030 79 300 25.0 SEP. 07 1022 214 186 26.0 JUN. 01 1015 300 209 -- K = non-ideal count E = estimate 57 OCEANO ATLANTICO 0382 uno Tortuguero BARCELONETA VEGA BAJA @ • 71 166 68 MANATI 0381 a VEGA ALTA E 0142 Gm Drainage boundaries indeterminate in limestone terrane Florida . 055 \ 035950./ II\ ..--... .. .....-- ..... ,/ CI ES ) ,..,'''.-- ..—.....---., Limestone i s ki"\-;://. \._ ..._.— • Igneous and •.,..„ MOROVIS /00 0350 sedimentary rocks /--- C' _.—............- 0 0312 '0 r o Drainage Rio Cibuco basin boundary do M0not7-...„ to fr) 0307 OROCOVIS ( —Drainage boundary Logo de otrullos Rio Grande de Arecibo basin Rio de la Plato basin ilaciog. \CanoI d, Aceitunas and , Rib coam. IL ego basin Island Gaiingo 4— tunnel to Rio Jacaguas basin ) EXPLANATION Rio Inabo'n basin / A 0350 SURFACE—WATER STATION AND NUMBER V 0307 QUALITY—OF—WATER STATION AND NUMBER • 142 WELL AND WELL NUMBER o 2 4 5 6 7KILOMETERS 1 6 MILES Figure 14.--Rio Grande de Manati basin. 58 RIO GRANDE DE MANATI BASIN 50030700 RIO OROCOVIS NEAR OROCOVIS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°14'20", long 66°22'58", at flat low bridge about 300 ft (91 m) northwest of Highway 568, 1.0 mi (1.6 km) north of Orocovis plaza. DRAINAGE AREA.--10.1 sq mi (26.2 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN. OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORMr TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, HARD- FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER AS DATE (CFS) (UMMOS) UNITS) (DEG C) (NTU) CMG/L) ATION) (MG/L) 100 ML) 100 ML) CAC03) NOV . 1982 22... 1350 6.5 331 8.3 22.0 4.6 8.6 105 45 2300 620 JAN , 1983 05... 1020 11 272 8.1 20.0 15 8.4 97 11 4400 3900 120 MAR 14... 1135 14 232 7.8 22.0 40 8.2 99 30 K3800 17000 MAY 03... 1310 13 272 8.3 23.5 70 8.0 99 24 K83000 9300 120 AUG 11... 1325 9.1 288 8.4 27.5 9.5 6.3 84 40 56000 13000 130 HARD­ MAGNE­ SODIUM POTAS- ALKA- CHLO- FLUO- SILICA. NESS. CALCIUM SIUM. SODIUM, AD- SIUMr LINITY SULFATE RIDE. RIDE, °IS- NONCAR­ DIS­ DIS­ DIS­ SORP- DIS- FIELD DIS- DIS- DIS- SOLVED 80NATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS DATE CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) SI02) NOV , 1982 22... 120 JAN r 1983 05... 0 30 11 14 .6 2.2 120 9.0 14 .10 35 MAR 14... 75 MAY 03... 5 28 11 14 .6 2.5 110 11 14 .20 32 AUG 11... 6 31 12 13 .5 1.7 121 8.9 14 .20 34 SOLIDS. SOLIDS. NITRO- SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN. GEN, MONIA + NITRO- NITRO.- TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEN. DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) DAY) CMG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) NOV , 1932 22... 4 <.010 2.3 .010 .19 .20 2.5 11 JAN . 1983 05... 187 5.6 5 .89 .010 .90 .040 .16 .20 1.1 4.9 MAR 14... 35 .97 .030 1.0 .080 .22 .30 1.3 5.8 MAY 03... 179 6.3 41 .95 .050 1.0 .080 .32 .40 1.4 6.2 AUG 11... 187 4.6 30 .74 .060 .80 .240 3.0 3.20 4.0 18 CHRO- SEDI- BARIUM. CADMIUM MIUM, LEAD. MERCURY SILVER, MENT. PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL SEOI- DIS- PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- MENT, CHARGE. TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE SUS- SUS- (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENDED PENDED DATE AS P) AS AS) AS 8A) AS CO) AS CR) AS P3) AS HG) AS SE) AS AG) (MG/L) (T/DAY) NOV r 1982 22... .460 JAN r 1983 05... .420 1 100 2 <1 5 .1 <1 <1 MAR 14... .080 76 2.9 MAY 03... .190 AUG 11... .420 2 200 1 <1 9 <.1 <1 3 K = non-ideal count 59 RIO GRANDE DE MANATI BASIN 50031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR LOCATION.--Lat 18°17'45", long 66°24'47", Hydrologic Unit 21010001, on left 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 sq mi (143.0 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1965 to current year. GAGE.--Water-stage recorder and concrete control. Altitude of gage is 440 ft (134.1 m), from topographic map. Feb. 2, 1966 to Apr. 27, 1967, staff gage read twice daily. REMARKS.--Records fair. Public water-supply pumpage, about 300 ft (91 m) above the station, influences low-flow discharges. AVERAGE DISCHARGE.--18 years (1966-83), 107 cu ft/s (3.030 cu m/s), 26.32 in/yr (669 mm/yr), 77,520 acre-ft/yr (95.6 cu hm/yr); median of yearly mean discharges 99 cu ft/s (2.80 cu m/s), 71,700 acre-ft/yr (88 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 35,000 cu ft/s (991 cu m/s) Oct. 9, 1970, gage height, 20.3 ft (6.19 m), from flood- marks, from rating curve extended above 200 cu ft/s (5.7 cu m/s) on basis of computations of flow over broad-crested weir and indirect measurements of peak flow at 13.5 ft (4.11 m), 16.0 ft (4.88 m) and 20.3 ft (6.19 m); minimum daily, 13 cu ft/s (0.368 cu m/s) Aug. 26, 1974, Oct. 21-23, 1978. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 3,500 cu ft/s (99.1 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Mar. 12 1515 5,940 168 6.51 1.984 May 11 2100 6,200 176 6.64 2.024 Apr. 21 0230 14,600 413 9.97 3.039 May 13 2045 *22,500 637 12.21 3.722 Minimum discharge, 25 cu ft/s (0.708 cu m/s) Apr. 17. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 62 33 160 154 44 31 32 67 79 53 45 31 2 47 32 99 120 44 32 32 64 79 66 50 34 3 63 31 31 102 42 31 31 66 74 63 45 39 4 62 31 75 92 41 32 33 60 73 73 40 30 5 66 31 68 33 43 32 32 54 71 74 36 32 6 46 33 59 79 41 30 32 53 68 72 34 60 7 36 45 53 80 40 31 32 52 66 69 33 66 3 36 39 51 73 39 31 30 64 64 59 34 44 9 36 39 46 80 36 31 29 63 64 52 35 51 10 34 43 46 89 37 23 28 48 61 50 33 35 11 34 42 58 71 37 27 28 542 57 51 34 37 12 65 309 44 69 36 1160 29 519 57 50 36 33 13 95 503 50 64 36 305 28 1490 54 47 36 32 14 74 173 46 101 36 114 29 731 56 45 34 29 15 52 131 162 203 37 74 37 316 54 45 32 29 16 48 74 161 89 35 56 31 169 188 46 33 29 17 46 56 95 73 35 49 28 123 156 51 51 29 13 46 47 74 66 35 46 151 411 120 52 58 46 19 45 43 62 62 34 43 190 373 100 47 35 60 20 45 '44 79 59 35 41 247 393 90 46 34 36 21 39 63 116 58 56 39 2730 283 30 44 74 39 22 38 53 91 56 41 33 254 213 70 44 130 43 23 35 56 72 54 35 37 134 166 64 45 50 44 24 34 103 64 54 34 37 169 129 62 51 44 43 25 34 100 61 49 34 35 95 118 6C 43 99 35 26 33 82 255 43 33 37 77 115 56 40 63 31 27 33 174 600 47 33 36 57 110 59 41 63 34 28 34 313 30C 47 32 43 64 95 63 40 45 29 29 48 182 203 46 --- 36 129 90 55 44 38 32 30 37 286 132 46 34 115 88 55 50 35 29 31 36 --- 151 44 33 --- 82 --- 43 33 --- TOTAL 1439 3193 3614 2353 1061 2630 4993 7157 2255 1606 1442 1152 MEAN 46.4 106 117 76.1 37.9 84.8 156 231 75.2 51.8 46.5 33.4 MAX 95 508 600 203 56 1163 2730 1490 138 74 130 66 MIN 33 31 44 44 32 27 28 43 54 40 32 29 CFSM IN. .34 .97 1.92 2.15 2.12 2.44 1.33 1.59 .69 .72 1.54 1.77 3.01 3.36 4.19 4.22 1.36 1.52 .94 1.03 .34 .97 .70 .73 AC-FT 2850 6330 7170 4680 2100 5220 9900 14200 4470 3193 2360 2280 CAL YR 1982 TOTAL 27046 MEAN 74.1 MAX 1290 MIN 16 CFSM 1.34 IN 18.23 AC-FT 53650 WTR YR 1983 TOTAL 32900 MEAN 90.1 MAX 2780 MIN 27 C 5SM 1.63 IN 22.17 AC-FT 65260 60 RIO GRANDE DE MANATI 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 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL♦ FECAL, FLOWe CON- PH TUR- OXYGEN. (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV r 1982 19... 1205 43 273 8.2 27.0 5.1 7.6 98 27 K200 170 JAN a. 1983 05... 1330 32 253 8.2 23.0 7.3 8.6 102 10 410 280 MAR 10... 1245 29 282 8.5 25.5 1.8 8.4 105 11 K30 K27 MAY 03... 1020 57 255 8.0 24.5 21 9.1 111 <10 K760 650 AUG 11... 1035 33 266 7.4 28.0 2.7 8.4 109 31 K130 80 HARD- MAGNE- SODIUM POTAS.. ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM, SODIUM, AD- STUN, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- On- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1982 19... 100 JAN , 1983 05... 110 5 24 11 13 .6 1.5 100 8.0 13 <.10 MAR 10... 110 MAY 03... 100 6 24 10 13 .6 2.5 95 10 12 .10 AUG 11... 110 6 26 11 13 .6 1.8 104 8.0 14 .20 SOLIDS. SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA 4' NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENOED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 19... 12 <.010 .80 .03C 1.5 1.50 2.3 JAN e 1933 05... 30 160 35.6 6 <.010 .90 .030 .37 .40 1.3 MAR 10... 6 .27 .030 .30 .020 .18 .20 .50 MAY 03... 28 157 24.1 <1 .59 .010 .60 .010 .19 .20 .80 AUG 11... 28 164 14.6 2 <.010 .20 .030 .17 .20 .40 CHRO- BARIUM, CADMIUM MIUM, LEAD. MERCURY NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) NOV r 1982 19... 10 .070 JAN e 1983 05... 5.8 .210 1 100 2 <1 4 <.1 <1 <1 MAR 10... 2.2 .060 MAY 03... 3.5 .090 AUG 11... 1.8 .050 2 100 1 <1 2 <.1 <1 <1 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CPS) (UMHOS) (DEG C) OCT, 07 1000 36 210 25.0 JUN, 21 1120 81 210 28.5 DEC. 16 1220 156 244 22.0 JUL, 18 1050 51 240 28.0 FEB. 02 1230 45 299 23.5 SEP, 06 1436 30 252 29.5 APR, 08 1245 28 265 26.0 K = non-ideal count 61 RIO GRANDE DE MANATI BASIN 50035000 RIO GRANDE DE MANATI AT CIALES, PR LOCATION.--Lat 18°19'26", long 66°27'36", Hydrologic Unit 21010001, on left bank, 1.6 mi (2.6 km) upstream from Hwy 145 bridge, 0.8 mi (1.3 km) downstream from Quebrada Saliente, 0.9 mi (1.4 km) upstream from Quebrada Cojo Vale's, and 1.2 mi (1.9 km) southeast of Ciales. DRAINAGE AREA.--128 sq mi (332 sq km), excludes 6.0 sq mi (15.5 sq km), the runoff from which is diverted through 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 km) downstream, drainage area 132 sq mi (342 sq km). GAGE.--Water-stage recorder. Altitude of gage is 140 ft (42.7 m), from topographic map. Prior to Apr. 1, 1962 , staff gage, read twice daily, at site 100 ft (30.5 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. AVERAGE DISCHARGE.--23 years (1961-83), 261 cu ft/s (7.392 cu m/s) 27.69 in/yr (703 mm/yr), 189,100 acre-ft/yr (233 cu hm/yr); median of yearly mean discharges, 246 cu ft/s (6.97 cu m/s), 178,000 acre-ft/yr (219 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 125,000 cu ft/s (3,540 cu m/s) Oct. 9, 1970, gage height, 24.0 ft (7.32 m), from floodmark, from rating curve extended above 3,000 cu ft/s (85.0 cu 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 daily, 24 cu ft/s (0.680 cu m/s) July 13-15, 1974. 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 above base of 7,000 cu ft/s (198 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Mar. 12 1500 12,900 365 8.76 2.670 May 13 2045 25,000 708 11.88 3.621 Apr. 21 0300 *29,100 824 12.74 3.883 June 16 0845 7,680 217 6.89 2.100 May 11 2030 14,500 411 9.24 2.816 Minimum discharge, 51 cu ft/s (1.444 cu m/s) Mar. 11. DISCHARGE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 163 65 385 322 92 69 65 188 180 132 76 71 2 112 62 228 260 90 67 64 156 163 142 89 71 3 115 57 180 220 89 66 63 185 157 147 95 74 4 305 56 158 195 88 65 64 203 173 162 71 68 5 238 54 144 176 88 61 65 209 153 160 67 67 6 130 57 127 170 87 67 65 151 147 149 67 126 7 127 68 116 165 85 65 63 129 140 136 65 290 8 173 60 107 154 82 64 60 418 133 127 64 135 9 103 74 102 156 86 63 56 323 129 116 67 94 10 83 98 134 150 85 59 57 202 123 110 62 71 11 76 105 230 139 79 54 56 1790 120 152 60 74 12 89 590 119 132 75 4850 56 1400 114 152 64 88 13 179 1420 106 129 75 998 53 3250 115 116 64 68 14 241 429 113 126 74 334 84 3500 118 108 64 63 15 187 333 360 434 75 183 178 980 112 105 62 60 16 130 167 483 182 76 134 75 590 1570 101 60 58 17 101 125 244 152 74 113 62 430 1300 106 96 60 18 103 99 174 138 73 102 395 850 1680 110 100 62 19 125 113 141 123 73 95 336 1100 587 98 69 93 20 97 96 199 122 74 90 1080 1050 351 93 63 66 21 92 218 271 116 119 85 3390 666 252 85 104 66 22 87 189 221 113 103 82 790 749 216 83 228 70 23 77 302 167 110 82 80 406 563 190 84 91 74 24 69 354 142 100 78 77 367 353 171 91 75 70 25 65 304 133 105 76 76 231 290 162 85 118 1D8 26 62 187 572 104 74 77 180 268 155 81 88 128 27 62 474 1580 102 72 74 150 244 153 80 113 73 28 61 752 804 95 71 83 138 215 164 77 99 76 29 130 500 527 93 --- 77 467 2C6 146 79 82 88 30 78 633 346 92 71 382 209 139 83 77 65 31 73 --- 307 92 63 --- 183 --- 77 71 --- TOTAL 3733 8041 8920 4775 2295 8449 14503 21055 9313 3427 2571 2577 MEAN 120 268 288 154 82.0 273 483 679 310 111 82.9 85.9 MAX 305 1420 1580 434 119 4850 8390 3500 1680 162 228 290 MIN 61 54 102 92 71 54 56 129 112 77 60 53 CFSM .94 2.09 2.25 1.20 .64 2.13 3.77 5.31 2.42 .87 .65 .67 IN. 1.08 2.34 2.59 1.39 .67 2.46 4.21 6.12 2.71 1.00 .75 .75 AC-FT 7400 15950 17690 9470 4550 16760 28770 41760 18470 6800 5100 5110 CAL YR 1982 TOTAL 62990 MEAN 173 MAX 5520 MIN 48 CFSM 1.35 IN 18.31 AC-FT 124900 WTR YR 1983 TOTAL 89659 MEAN 246 MAX 8390 MIN 54 CFSM 1.92 IN 26.06 AC-FT 177800 62 RIO GRANDE DE MANATI BASIN 50035000 RIO GRANDE DE MANATI AT CIALES, PR--Continued WATER-DUALITY RECORDS PERIOD OF RECORD.--WATER YEARS 1979 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1933 STREAMFIOW, SPECIFIC CON- TEMPERA- STREAMFIOW, SPECIFIC CON- TEMPERA­ OATS TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMNOS) (DEG C) (CFS) (UMMOS) (DEG C) OCT, 06 0445 144 190 25.0 MAY, 04 1249 185 207 26.5 NOV, 15 1435 274 173 26.0 JUN, 21 1400 251 186 30.0 DEC, 2C 1225 190 260 23.0 JUL, 18 1305 112 222 31.0 JAN, 05 1335 164 245 24.0 AUG, 10 1105 63 246 23.5 FEB, 01 1200 90 300 25.0 SEP, 07 1438 95 221 29.0 APR, 07 1353 64 275 27.5 63 RIO GRANDE DE MANATI BASIN 50035500 RIO GRANDE DE MANATI AT HIGHWAY 149 AT CIALES, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°20'46", long 66°28'06", at bridge on Highway 149, about 800 ft (244 m) upstream from confluence with Rio Cialitos, 0.5 mi (0.8 km) north of 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. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN. OXYGEN COLT- STREP- SPE- CIS- DEMAND. FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL. FECAL, FLOW. CON- PH TUR- OXYGEN, (PER- ICAL 0.7 ICE AGAR INSTAN- DUCT- (STAND- TEMPER- 810- pis- CENT (HIGH um-m, (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (PG/L) 100 ML) 100 ML) NOV • 1982 12... 1145 E120 217 7.7 25.0 57 6.0 73 14 45000 43000 JAN • 1983 24... 1340 105 252 8.1 24.0 3.6 8.8 105 39 190 K30 MAR 11... 1050 60 260 8.3 26.5 2.1 8.4 105 <10 K30 K180 MAY 23... 0900 E560 161 7.4 24.0 26 8.4 100 <10 K1900 4700 AUG 30... 1330 65 240 8.2 29.5 <1.0 8.0 105 16 420 K90 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS. CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE. RIDE. NESS NONCAR-.. DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV • 1982 12... JAN • 1933 24... 96 MAR 11... MAY 23... 65 AUG 30... 93 79 0 23 9.3 13 .6 1.8 98 - 100 6 16 6.0 8.9 .5 1.3 59 4 23 8.7 12 .6 1.8 89 10 11 .10 7.4 9.5 <.10 9,3 13 .10 SOLIDS. SOLIDS. NITRO- SILICA. SUM OF SOLIDS. RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN. GEN. GEN, GEN. GEN. MONIA + SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) NITRO- GEN, TOTAL (MG/L AS N) NOV • 1982 12... -- 107 .58 .020 .60 .050 .95 1.00 1.6 JAN • 1933 24... 27 154 43.6 2 .59 .010 .60 .040 <.10 MAR 11... 13 <.010 .20 .020 .23 .30 .50 MAY 23... 24 109 26 .59 .010 .60 .020 .38 .40 1.0 AUG 30... 28 149 26.2 6 <.010 .40 <.010 .30 .70 NITRO- GEN. TOTAL (MG/L DATE AS NO3) CHRO- 3ARIUM, CADMIUM MIUM, LEAD. MERCURY SILVER. PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV r 1982 12... 7.1 .140 JAN e 1983 24... .070 1 100 1 <1 15 .1 <1 <1 MAR 11... 2.2 .060 MAY 23... 4.4 .060 AUG 30... 3.1 .070 1 100 1 <1 5 <.1 <1 <1 E = estimate K = non-ideal count DATE 64 RIO GRANDE DE MANATI BASIN 50035950 RIO CIALITOS AT HIGHWAY 649 AT CIALES, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°20'18", long 66°28'28", 100 ft (30 m) upstream from bridge on Highway 649, 0.7 mi (1.1 km) upstream from mouth, and about 0.4 mi (0.6 km) west of Ciales plaza. DRAINAGE AREA.--17.0 sq mi (44.0 sq km). PERIOD OF RECORD.--Water years 1969-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLT- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVEC CHEM- FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOY r 1982 12... 1030 25 208 7.8 23.0 45 8.3 97 15 K8200 9500 JAN , 1983 24... 1125 20 243 8.2 21.5 1.0 9.2 104 53 840 1500 MAR 11... 1405 8.9 265 8.4 26.0 1.4 8.5 106 <10 1(37 360 MAY 23... 1045 69 187 7.9 24.0 8.0 3.2 98 <10 K1100 3600 AUG 30... 1040 11 243 8.2 26.0 6.0 3.3 103 11 K860 840 HARD- MAGNE- SODIUM ROTAS ALKA- CHLO FLUO... MARD NESS, CALCIUM SIUM, SODIUM, 4D- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD CIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED CMG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS 504) AS CL) AS F) NOV , 1982 12... 79 JAN r 1983 24... 95 0 27 6.8 12 .6 1.2 93 7.0 11 .10 MAR 11... 110 MAY 23... 75 3 22 4.8 9.0 .5 1.6 72 15 9.2 <.10 AUG 30... 100 5 30 6.6 11 .5 1.6 97 9.8 12 .20 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRC- GEN,AM- CIS- CONSTI- DIS- AT 105 GEN, GEN, GEN' GEN. GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. C. NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENOED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV r 1932 12... 45 .98 .020 1.0 .03C .77 .90 1.8 JAN , 1983 24... 31 155 8.4 2 <.010 .90 .020 .28 .30 1.2 MAR 11... 14 <.010 .60 .020 .28 .30 .90 MAY 23... 26 131 24.4 5 <.010 .70 <.010 .40 1.1 AUG 30... 29 158 4.7 10 <.010 .80 <.010 .50 1.3 CHRO- 3ARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS Pa) AS HG) AS SE) AS AG) NOV r 1982 12... 8.0 .100 JAN , 1983 24... 5.3 .190 2 100 1 <1 12 .1 <1 <1 MAR 11... 4.0 .080 MAY 23... 4.9 .070 AUG !0... 5.8 .080 1 <100 1 <1 5 <.1 <1 <1 K = non-ideal count 65 RIO GRANDE DE MANATI BASIN 50038100 RIO GRANDE DE MANATI AT HIGHWAY 2 NEAR MANATI, PR LOCATION.--Lat 18°25'52", long 66°31'37", Hydrologic Unit 21010002, at bridge on Highway 2, and 2.3 mi (3.7 km) west of Manati. DRAINAGE AREA.--197 sq mi (510 sq km), approximately, of which about 38 sq mi (98 sq km) is partly or entirely noncontributing, excludes 6.0 sq mi (15.5 sq km) upstream from Lago El Guineo and Lago de Matrullas. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--1963-68 (annual maximum discharge only), February 1970 to current year. GAGE.--Water-stage recorder. Altitude of gage is 14 ft (4.3 m), from topographic map. Prior to 1968 crest-stage gage at same site and datum 3.57 ft (1.088 m) lower. REMARKS.--Records good. AVERAGE DISCHARGE.--13 years (1971-83), 375 cu ft/s (10.62 cu m/s), 25.85 in/yr (657 mm/yr), 271,700 acre-ft/yr (335 cu hm/yr); median of yearly mean discharges, 335 cu ft/s (9.49 cu m/s), 243,000 acre-ft/yr (300 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 119,000 cu ft/s (3,370 cu m/s) Oct. 9, 1970, gage height, 33.3 ft (10.15 m) from rating curve extended above 15,000 cu ft/s (425 cu m/s) on basis of slope-area measurement of peak flow; minimum, 50 cu ft/s (1.42 cu m/s) Sept. 4, 1977, Aug. 12-14, 1978. EXTREMES OUTSIDE PERIOD OF RECORD.--Approximate gage heights to gage datum of major floods, pointed out by local residents, are as follows: Sept. 13, 1928, 36.6 ft (11.16 m), Sept. 27, 1932, 36.3 ft (11.06 m ), and Aug. 4, 1945, 34.3 ft (10.45 m). EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 9,000 cu ft/s (255 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Mar. 12 1915 13,900 394 28.70 8.748 May 14 0030 20,800 589 29.52 8.998 Apr. 21 0630 *39,600 1,121 30.84 9.400 Minimum discharge, 86 cu ft/s (2.436 cu m/s) Sept. 6. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 245 116 597 427 143 104 106 290 309 181 116 101 2 211 111 396 353 144 102 103 236 233 183 134 94 3 200 106 332 307 142 102 102 238 267 191 151 102 4 261 103 294 276 144 101 100 293 267 201 129 97 5 503 101 273 262 145 101 100 295 248 226 115 91 6 290 103 255 247 142 103 102 241 241 204 113 90 7 200 115 237 233 132 106 99 203 235 190 106 267 8 276 110 224 224 135 101 96 253 223 180 103 278 9 203 151 213 217 137 101 92 613 215 164 108 170 10 169 133 210 215 136 99 90 266 207 155 106 121 11 152 193 331 209 133 95 90 375 205 187 100 114 12 144 295 233 204 128 4023 92 2300 209 249 115 129 13 231 2040 209 195 126 2060 92 1910 195 170 119 113 14 267 743 322 187 123 492 111 5650 194 152 105 101 15 229 510 343 444 123 304 195 1310 189 146 102 101 16 284 349 747 251 123 229 134 729 1290 140 99 101 17 179 283 395 196 119 189 108 522 902 140 106 98 18 158 241 303 173 118 169 304 1090 2090 160 176 96 19 241 240 259 165 117 157 218 1530 765 146 123 135 20 169 307 292 168 117 141 609 1470 456 133 102 110 21 161 311 413 160 143 141 12200 912 339 131 111 103 22 148 486 366 155 155 135 1260 737 289 125 300 114 23 139 415 299 152 126 130 612 894 260 123 168 116 24 128 473 264 154 118 127 506 512 238 127 125 114 25 120 682 253 150 115 122 365 552 224 130 147 121 26 114 370 586 149 114 122 237 475 211 122 149 211 27 112 566 2000 147 110 121 247 467 208 117 154 129 21 126 1000 1130 144 107 123 220 371 216 117 211 126 29 154 700 749 144 --- 125 237 348 199 116 150 136 30 135 696 511 143 114 714 380 189 123 118 126 31 122 --- 404 143 109 --- 383 --- 121 109 --- TOTAL 6066 12054 13445 6611 3621 10252 19631 26415 11363 4872 4140 3310 MEAN 196 402 434 213 129 331 655 852 379 157 134 127 MAX 508 2043 2000 444 155 4020 12200 5650 2C90 249 300 271 MIN 112 101 209 143 107 95 90 203 119 116 99 90 CFSM 1.00 2.04 2.20 1.03 .66 1.68 3.33 4.33 1.92 .10 .68 .65 IN. 1.15 2.28 2.54 1.25 .68 1.94 3.71 4.99 2.15 .92 .78 .72 AC-FT 12030 23910 26670 13110 7180 20330 39000 52390 22540 9660 3210 7560 CAL YR 1982 TOTAL 94365 MEAN 259 MAX 7300 MIN 80 CFSM 1.32 IN 17.12 AC-FT 187200 WTR YR 1983 TOTAL 122310 MEAN 335 MAX 12200 MIN 90 CFSM 1.70 IN 23.10 AC-FT 242600 66 RIO GRANDE DE MANATI BASIN 50038100 RIO GRANDE DE MANATI AT HIGHWAY 2 NEAR MANATI, PR--Continued (National stream-quality accounting network station) WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 DATE STREAM- FLOW, INSTAN- TIME TANEOUS (CPS) SPE- CIFIC CON- DUCT- ANCE (UMMOS) PH (STAND- ARD UNITS) TEMPER- ATURE (DEG C) TUR- BID- ITY (NTU) OXYGEN, OXYGEN COLI- STREP- DIS- DEMAND, FORM, TOCOCCI SOLVED CHEM- FECAL, FECAL, HARD- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS On- CENT (HIGH UM-MF (COLS. (MG/L SOLVED SATUR- LEVEL) (COLS./ PER AS (MG/L) ATION) (MG/L) 100 ML) 100 ML) CAC03) OCT , 1982 08... 1345 324 250 7.7 31.0 30 8.0 109 48 <10 830 99 NOV 30... 1400 432 235 7.2 25.0 60 7.4 90 12 4100 K620 94 FEB , 1983 02... 1310 145 310 7.5 25.0 4.4 9.2 112 16 360 3200 140 APR 11... 1115 90 325 7.9 26.0 8.0 8.4 104 20 K470 390 140 JUN 10... 1245 207 295 8.0 29.0 2.1 8.3 108 33 510 K87 130 AUG 04... 1355 126 280 7.7 30.0 3.3 7.8 104 22 120 HARD- NESS, NONCAR- BONATE (MG/L DATE CAC03) CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM, DIS- SOLVED (MG/L AS NA) SODIUM AD- SORP- TION RATIO SOLIDS, POTAS- ALKA- CHLO- FLUO- SILICA., RESIDUE SLUM, LINITY SULFATE RIDE, RIDE, DIS- AT 180 DIS- FIELD DIS- DIS- DIS- SOLVED DEG. C SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L DIS- (MG/L AS (MG/L (MG/L (MG/L AS SOLVED AS K) CAC03) AS SO4) AS CL) AS F) SI02) (MG/L) OCT , 1982 03... 0 29 6.4 10 .5 1.2 110 7.0 11 .10 20 160 NOV 30... 14 27 6.4 10 .5 2.1 80 11 9.5 <.1C 23 162 FEB , 1983 02... 6 40 3.6 13 .5 1.4 130 8.7 11 <.10 22 179 APR 11... 0 43 7.8 11 .4 1.6 140 8.0 14 .10 18 190 JUN 10... 0 38 3.1 12 .5 1.9 130 9.0 13 .20 21 174 AUG 04... 5 37 7.8 11 .4 1.9 120 8.6 13 .10 20 201 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED DATE (MG/L) SOLIDS, NITRO- NITRO- NITRO- NITRO- PHOS- PHOS- SOLIDS, RESIDUE GEN, GEN, GEN, GEN,AM- PHOS- PHORUS, PHATE, DIS- AT 105 NO2+NO3 AMMONIA AMMONIA MONIA + PHOS- PHOS- PHORUS, ORTHO, ORTHO, SOLVED DEG. Cr DIS- DIS- On- ORGANIC PHORUS, PHORUS DIS- DIS- DIS- (TONS. SUS- SOLVED SOLVED SOLVED TOTAL TOTAL TOTAL SOLVED SOLVED SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS NH4) AS N) AS P) AS PO4) AS P) AS P) AS 904) OCT , 1932 3... 151 140 16 .72 .050 .06 .70 .150 .46 .080 .090 .28 NOV 30... 137 211 80 .97 .080 .10 .80 .200 .61 .090 .090 .28 FEB , 1983 02... 183 70.1 5 .72 .060 .08 .20 .130 .40 .080 .070 .21 APR 11... 183 45.9 14 .48 <.010 .40 .100 .31 .060 .070 .21 JUN 10... 182 97.2 6 .31 <.010 .40 1.30 4.0 .050 .040 .12 AUG 4... 172 68.4 18 E = estimate K = non-ideal count 67 RIO GRANDE DE MANATI BASIN 50038100 RIO GRANDE DE MANATI AT HIGHWAY 2 NEAR MANATI, PR - -Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 ALUM- BERYL- CHRO- INUM, ARSENIC BARIUM, LIUM, CADMIUM MIUM, COBALT, COPPER, IRON, LEAD, LITHIUM DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DI S- SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS AL) AS AS) AS BA) AS BE) AS CD) AS CR) AS CO) AS CU) AS FE) AS PB) AS LI) OCT , 1912 08... 30 2 49 <1 <1 <1 <3 11 <3 <1 <4 NOV 30... FEB p 1933 02... 10 1 49 <1 <1 1 <3 6 12 2 <4 APR 11... JUN 10... 20 1 56 1 2 <1 3 10 15 <1 4 AUG 04... 20 1 83 <1 <1 <1 <3 2 10 <1 7 MANGA- MOLYB- SELE- STRON- VANA- MENT, NESE, MERCURY DENUM, NICKEL, NIUM, SILVER, TIUM, DIUM, ZINC, SEDI- OIS- OIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- MENT, CHARGE, SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SUS- SUS- (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENDED PENDED DATE AS MN) AS HG) AS MO) AS NI) AS SE) AS AG) AS SR) AS V) AS ZN) (MG/L) (T/DAY) OCT r 1982 OB... 17 <.1 <10 1 <1 <1 140 6.0 4 62 54 NOV 30... 99 129 FEB , 1983 02... 23 .2 <10 2 <1 <1 190 <6.0 16 17 6.7 APR 11... 58 14 JUN 10... 26 .1 10 <1 <1 <1 180 10 5 23 13 AUG 04... 29 <.1 <10 1 <1 <1 180 9.0 <3 23 7.8 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 0915 101 340 25.0 MAY, 03 1127 209 261 26.5 JAN, 05 1010 258 296 24.0 JUL, 07 1049 189 266 27.5 MAR, 09 1005 101 325 25.0 AUG, 25 0934 116 27.5 CHLOR- DI- DI- ENDO- PCB, ALDRIN, DANE, ODD, DOE, DDT, AZINON, ELORIN SULFAN, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1983 10... 1245 <.10 <.01 <.10 <.01 <.01 <.01 .01 <.01 <.01 HEPTA- METH- METHYL METHYL HEPTA- CHLOR MALA- OXY- PARA- TRI- ENDRIN, ETHION, CHLOR, EPDXIDE LINOANE THION, CHLOR, THION, THION, MIREXr TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN , 1983 10... <.01 .01 <.01 <.01 <.01 .01 <.01 .01 .01 <.01 NAPH- THA- LINES., PARA- POLY- PER- TOX- TOTAL THION, CHLOR. THANE APHENE, TRI- 2,4-D, 2,4,5-7 2, 4-CP SILVEX, TOTAL TOTAL TOTAL TOTAL THION TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1983 10... .01 <.10 <.10 <1 .01 <.01 <.01 <.01 <.01 68 RIO GRANDE DE MANATI BASIN 50038100 RIO GRANDE DE MANATI AT HIGHWAY 2 NEAR MANATI, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 SED. SUSP. STREAM- SEDI- SIEVE FLOW• MENT. DIAM. INSTAN- SUS- 7( FINER TIME TANEOUS PENDED THAN DATE (CFS) (MG/L) .062 MM OCT . 1982 08... 1345 324 62 85 NOV 30... 1350 472 99 69 FEB . 1983 02... 1310 145 17 65 APR 11... 1115 90 58 97 JUN 10... 1245 207 23 48 AUG 04... 1355 126 23 61 BED MAT. STREAM- SIEVE FLOW, DIAM. INSTAN- FINER TIME TANEOUS THAN DATE (CFS) .062 MM AUG . 1983 04... 1200 E126 2 E = estimate 69 LAGUNA TORTUGUERO BASIN 50038200 LAGUNA TORTUGUERO OUTLET NEAR VEGA BAJA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°28'29", long 66°26'50", at bridge on Highway 686, 4.2 mi (6.8 km) northeast of Manati, and 4.4 mi (7.1 km) northwest of Vega Baja plaza. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1964-66, 1969-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI ALKA- STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, LINITY FLOW, CON- PH OXYGEN, (PER- ICAL 0.7 KF AGAR FIELD INSTAN- DUCT. . (STAND- TEMPER- DIS- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARD ATURE SOLVED SATUR- LEVEL) (COLS./ PER AS DATE (CFS) (UMHOS) UNITS) (DEG C) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CACO3) NOV , 1982 05... 1515 22 1680 7.9 29.0 8.1 106 65 K10 K82 130 FES , 1983 02... 0940 14 1330 7.7 25.0 7.2 87 48 K3 89 150 MAR 14... 1025 14 2900 8.0 27.0 7.6 96 76 K13 550 160 MAY 09... 1500 19 1390 8.0 31.5 9.4 129 110 20 600 260 AUG 04... 1035 13 2000 8.0 29.5 8.8 116 74 K19 K10 93 SOLIDS, NITRO- RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GENrAM- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO.' NITRO- PHOS- DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEN, PHORUS, SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL PENDEO (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) AS P) NOV , 1982 05... 6 .63 .020 .70 .340 .86 1.20 1.9 8.4 .030 FEB , 1933 02... 4 .63 .020 .70 .730 .57 1.30 2.0 8.9 .010 MAR 14... <1 .93 .020 1.0 .640 .26 .90 1.9 8.4 <.010 MAY 09... 8 .58 .020 .60 .030 .82 .90 1.5 6.6 .010 AUG 04... 2 .43 .020 .50 .120 1.2 1.30 1.8 8.0 .030 K = non-ideal count 71 OCEAN° ATLANTICO 039750 16 V V039650 169 0397 DORADO," Laguna Tor fuguero 0395 VEGA BAJA! •151 TOA BAJA • • 156 t , 167 070 o MANATI 1550 EGA ALTA : A, 11,62 Drainage boundaries indeterminate TOA ALTA in limestone terrane O Rfo Limestone Igneous and sedimentary rocks CIALES S MOROVIS NARANJITO S Rtit Greed. be Mottatcbesit\ Rio di la Plata basin Drainage boundary EXPLANATION A 038320 SURFACE—WATER STATION AND NUMBER A 0390 LOW—FLOW STATION AND NUMBER V 0397 QUALITY—OF— WATER STATION AND NUMBER • 70 WELL AND WELL NUMBER 4 7KILOMETERS 6MILES Figure 15.--Rio Cibuco basin. 72 RIO CIBUCO BASIN 50038320 RIO CIBUCO BELOW COROZAL, PR LOCATION.--Lat 18°21'13", long 66°20'07", Hydrologic Unit 21010001, on right bank, 150 ft (46 m) downstream from Rio Corozal, and 1.4 mi (2.3 km) northwest of Corozal. DRAINAGE AREA.--15.1 sq mi (39.1 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--May 1969 to current year. GAGE.--Water-stage recorder. Altitude of gage is 195 ft (59.4 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--14 years (1970-83), 29.3 cu ft/s (0.830 cu m/s), 26.35 in/yr (669 mm/yr), 21,230 acre-ft/yr (26.2 cu hm/yr); median of yearly mean discharges, 31 cu ft/s (0.88 cu m/s), 22,500 acre-ft/yr (28 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 13,600 cu ft/s (385 cu m/s) Nov. 7, 1979, gage height, 19.80 ft (6.025 m), from rating curve extended above 100 cu ft/s (2.83 cu m/s) on basis of float and slope-area measurements of peak flow; minimum daily discharge, 1.3 cu 't/s (0.037 cu m/s) July 24-26, 1977. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 2,500 cu ft/s (70.8 cu m/s) and maximum (*): Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Apr. 21 0100 *2,800 79.3 11.21 3.417 Minimum discharge, 5.4 cu ft/s (0.153 cu m/s) Apr. 16. DISCHARGE, IN CU9IC FeET PER SECOND' WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NCV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 32 9.5 21 45 13 7.6 12 16 24 14 10 11 2 26 9.4 19 35 11 7.6 11 15 23 13 53 12 3 41 9.1 20 32 11 7.3 11 15 22 14 17 11 4 23 9.4 19 31 11 7.4 12 15 21 34 14 11 5 16 9.3 18 31 12 7.2 12 16 20 24 10 11 6 12 8.3 17 33 10 7.9 10 15 19 20 9.8 26 7 11 8.7 16 23 10 8.3 9.0 15 19 16 9.0 42 3 11 3.6 16 25 10 7.7 8.0 29 19 14 9.3 19 9 10 10 15 25 11 7.3 7.3 18 19 14 9.9 13 10 9.5 63 15 22 10 7.1 7.2 14 18 14 8.7 12 11 9.7 25 15 21 9.9 7.4 7.3 23 18 11 9.3 14 12 16 190 14 22 10 373 6.6 39 17 11 101 12 13 13 104 14 21 10 47 6.2 175 17 11 27 10 14 11 40 15 19 9.4 27 6.2 36 17 13 20 9.9 15 9.8 27 63 20 9.6 16 6.2 45 17 13 13 12 16 9.1 22 26 13 9.4 13 6.0 29 17 1 7 13 11 17 8.7 20 20 13 9.3 12 7.2 23 27 14 45 10 18 16 26 17 17 9.1 12 21 181 23 15 23 112 19 14 20 16 23 8.8 12 11 147 17 13 14 34 20 12 22 19 15 9.2 14 31 130 16 11 12 22 21 11 .23 43 15 17 15 492 79 15 11 54 59 22 10 21 20 15 11 13 65 90 15 10 33 43 23 9.5 22 19 15 10 11 48 56 14 12 17 25 24 9.0 17 18 15 9.4 13 66 43 14 15 20 22 25 8.9 18 25 15 9.3 14 30 35 15 11 25 17 25 10 25 274 15 8.7 14 24 109 14 10 19 15 27 9.0 30 133 14 3.0 14 21 47 15 10 20 13 28 8.9 74 94 13 3.2 14 20 33 16 9.9 17 13 29 11 43 60 13 14 18 23 13 11 13 13 30 9.9 28 44 13 14 17 28 13 10 12 12 31 11 --- 49 13 13 --- 25 --- 9.3 12 --- TOTAL 424.0 942.3 1179 655 285.3 758.8 1059.2 1628 534 424.2 675.5 646.9 MEAN 13.7 31.4 38.0 21.2 10.2 24.5 35.3 52.5 17.8 13.7 21.8 21.6 MAX 41 190 274 45 17 373 492 181 27 34 101 112 MIN 8.7 8.5 14 13 8.0 7.1 6.0 14 13 9.3 8.7 9.9 CFSM .91 2.03 2.52 1.40 .68 1.62 2.34 3.43 1.18 .91 1.44 1.43 IN. 1.04 2.32 2.90 1.62 .70 1.87 2.61 4.01 1.32 1.04 1.66 1.59 AC-FT 841 1970 2340 1300 566 1510 2100 3230 1060 341 1340 1280 CAL YR 1982 TOTAL 9221.7 MEAN 25.3 MAX 531 MIN 6.1 CFSM 1.68 IN 22.72 AC-FT 13290 WTR YR 1983 TOTAL 9213.7 MEAN 25.2 MAX 492 MIN 6.0 CFSM 1.67 IN 22.70 AC-FT 13280 73 RIO CIBUCO BASIN 50038320 RIO CIBUCO BELOW COROZAL, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- On- DEMAND. FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL. FLOM' CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARO ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV • 1982 22... 1105 21 311 7.8 23.0 14 3.5 102 47 K5200 2300 JAN , 1983 07... 1135 28 333 7.9 22.0 6.5 7.8 90 13 2000 2100 MAR 09... 1135 7.8 380 7.6 24.0 1.2 7.6 91 <10 K1100 490 MAY 9... 1125 18 288 7.8 26.0 3.7 74.0 925 21 56000 K12000 AUG 10... 1125 9.2 343 8.0 27.5 4.1 6.6 84 22 2500 830 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS. CALCIUM SIUM, SODIUM. AD- SIUM. L/NITY SULFATE RIDE. RIDE. NESS NONCAR- DIS- CIS- DIS- SORP- DIS- FIELD DIS- DIS- On- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV r 1982 22... JAN r 1983 07... 130 MAR 09... MAY 9... 120 AUG 10... 120 100 0 31 12 19 .8 2.5 130 14 21 .10 130 0 30 11 18 .7 3.9 120 19 24 .20 30 10 18 .8 2.7 160 15 25 .20 SOLIDS,' SOLIDS. NITRO- SILICA. SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- N/TRO-.. NITRO- GENrAM- OIS- CONSTI- DIS- AT 105 GEN' GEN, GEN, GEN, GEN. MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GENr (MG/L On- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDEO (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV P 1982 22... 19 .87 .230 1.1 .530 .47 1.00 2.1 JAN r 1983 07... 32 210 16.0 8 1.0 .100 1.1 .730 .72 1.50 2.6 MAR 09... 8 .55 .150 .70 1.80 .00 1.80 2.5 MAY 9... 31 209 10.2 <1 .99 .610 1.6 1.70 .80 2.50 4.1 AUG 10... 31 228 5.7 13 .85 .250 1.1 1.10 .60 1.70 2.8 NITRO- GEN. TOTAL (MG/L DATE AS NO3) CHRO- BARIUM, CADMIUM MIUM. LEAD. MERCURY PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL PHORUSr ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL ERA3LE ERABLE ERA3LE ERABLE ERABLE (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS P) AS AS) AS BA) AS CO) AS CR) AS PB) AS HG) SELE- NIUM, TOTAL (UG/L AS SE) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) NOV r 1982 22... 9.3 .330 JAN , 1983 07... 12 .500 1 100 2 <1 6 <.1 <1 <1 MAR 09... 11 .660 MAY 9... 18 1.00 AUG 10... 12 .390 1 10D 2 49 7 <.1 <1 <1 STREAMFLOW. SPECIFIC CON- TEMPERA- STREAMFLCWr SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) OCT, 07 1245 12 361 27.0 JUN, 20 1320 16 305 30.0 DEC, 16 0930 27 300 21.5 JUL, 03 1005 14 359 26.5 FEB, 02 0900 12 347 21.0 SEP, 13 1052 11 313 26.0 APR. 08 0925 7.9 338 23.0 K = non-ideal count 74 RIO CIBUCO BASIN 50039500 RIO CIBUCO AT VEGA BAJA, PR LOCATION.--Lat 18°26'53", long 66°22'29", Hydrologic Unit 21010002, 0.6 mi (1.0 km) downstream from Rio Indio, and 0.8 mi (1.3 km) east of Vega Baja. DRAINAGE AREA.--99.1 sq mi (256.7 sq km), of which 25.4 sq mi (65.8 sq km), does not contribute directly to surface runoff. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1973 to current year. GAGE.--Water-stage recorder. Datum of gage is 7.79 ft (2.374 m) above mean sea level. REMARKS.--Records fair. AVERAGE DISCHARGE.--10 years (1974-83), 125 cu ft/s (3.540 cu m/s), 17.13 in/yr (435 mm/yr), 90,560 acre-ft/yr (112 cu hm/yr); median of yearly mean discharges, 116 cu ft/s (3.29 cu m/s), 84,000 acre-ft/yr (104 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 30,300 cu ft/s (858 cu m/s) Dec. 13, 1981, gage height, 18.84 ft (5.742 m), from rating curve extended above 3,000 cu ft/s) (85 cu m/s) on the basis of indirect measurements; minimum, 6.1 cu ft/s (0.173 cu m/s) July 24,25, 1977, gage height, 5.04 ft (1.536 m). EXTREMES OUTSIDE PERIOD OF RECORD.--Flood of Dec. 11, 1965 reached a stage of 26.2 ft (7.99 m), datum unknown, discharge about 28,000 cu ft/s (793 cu m/s). EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 3,200 cu ft/s (90.6 cu m/s) and maximum (*): Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) May 13 2245 *4,640 131 16.29 4.965 Minimum discharge, 20 cu ft/s (0.566 cu m/s) April 9, 10. CISCHARSE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 60 42 130 167 49 33 31 63 107 61 42 51 2 120 42 103 148 52 33 29 66 99 71 121 47 3 110 37 110 132 50 34 29 62 96 65 92 56 4 237 35 99 121 49 35 29 71 92 66 47 49 5 190 35 94 113 49 34 27 90 89 113 41 43 6 83 41 36 115 47 34 40 104 36 76 35 46 7 65 73 83 113 44 36 36 63 34 63 31 177 8 55 45 79 93 43 34 29 84 32 60 29 196 9 48 42 76 96 43 31 22 125 34 51 34 93 10 45 80 72 93 43 30 21 88 77 50 30 65 11 40 146 70 85 41 23 22 62 73 47 28 73 12 39 175 68 79 39 481 25 289 78 46 136 69 13 92 601 66 75 37 242 24 347 97 47 276 57 14 49 227 133 72 36 102 24 1110 110 44 92 50 15 42 126 193 84 38 64 26 294 99 42 76 61 16 39 101 170 73 38 52 26 192 91 46 68 71 17 42 89 110 67 37 43 29 156 76 82 108 83 13 55 30 39 66 35 39 63 422 11C 32 148 83 19 115 91 77 62 35 37 60 399 69 72 74 193 20 65 71 94 62 35 35 67 536 65 55 57 79 21 63 93 229 62 47 33 1730 273 64 43 99 162 22 60 165 148 60 52 31 379 292 59 46 250 226 23 53 91 108 53 40 35 539 282 57 45 103 146 24 46 77 99 58 37 41 256 178 58 64 78 112 25 41 90 111 55 35 39 141 224 59 52 90 90 26 39 99 461 54 34 41 118 336 58 43 121 73 27 47 135 878 53 32 39 33 283 61 41 31 64 23 34 256 362 51 31 43 79 164 74 43 90 60 29 67 215 294 50 --- 41 67 133 58 44 67 57 30 46 134 182 50 34 65 125 56 56 58 53 31 47 --- 168 49 33 --- 124 --- 53 53 --- TOTAL 2134 3531 5042 2521 1148 1167 4166 7347 2368 1776 2655 2695 MEAN 68.8 113 163 81.3 41.0 60.2 139 243 78.9 57.3 35.6 89.3 MAX 237 601 873 167 52 481 1730 1110 110 113 276 226 MIN 34 35 66 49 31 28 21 62 56 41 28 46 CFSM .69 1.19 1.65 .92 .41 .61 1.40 2.45 .80 .58 .36 .91 IN. .30 1.33 1.99 .95 .43 .70 1.56 2.83 .39 .67 1.00 1.01 AC-FT 4230 7003 10030 5000 2230 3700 3260 14970 4700 3520 5270 5350 CAL YR 1932 TOTAL 36773 MEAN 101 MAX 1130 MIN 30 CFSM 1.02 IN 13.3C AC-FT 72940 WTR YR 1983 TOTAL 37450 MEAN 103 MAX 1730 MIN 21 CFSM 1.04 IN 14.06 AC-FT 74280 RIO CIBUCO BASIN 75 50039500 RIO CIBUCO AT VEGA BAJA, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1972 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COIL- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) CMG/L) ATION) CMG/L) 100 ML) 100 ML) NOV , 1982 05... 1130 34 464 7.5 25.5 2.5 4.6 56 35 2300 220 JAN , 1983 20... 1155 62 414 7.5 24.0 5.4 5.6 66 35 4100 490 MAR 14... 1410 87 353 7.6 26.0 23 6.0 74 32 2300 310 MAY 02... 1350 67 370 7.8 26.5 16 5.8 72 15 46000 2000 AUG 4... 1415 46 359 7.8 23.5 1.4 5.6 72 20 K1800 610 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVE') SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/I (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS 504) AS CL) AS F) NOV , 1982 5... 170 JAN , 1983 20... 170 12 54 9.4 16 .6 2.7 162 14 22 .10 MAR 14... 130 MAY 02... 190 17 60 9.0 15 .5 3.2 170 19 23 .10 AUG 4... 160 14 52 8.3 14 .5 3.5 150 15 20 .20 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRC- GEN,AM- CIS- CONSTI- DIS- AT 105 GEN, GEN. GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 5... -- 8 1.5 .040 1.5 .020 .28 .30 1.8 JAN , 1983 20... 21 236 39.6 2 1.5 .060 1.6 .090 .61 .70 2.3 MAR 14... 26 1.8 .050 1.8 .170 .53 .70 2.5 MAY 02... 20 251 45.1 7 1.1 .080 1.2 .110 .29 .40 1.6 AUG 04... 19 222 27.6 33 1.4 .080 1.5 .120 .58 .70 2.2 CHRO- BARIUM, CADMIUM M/UM, LEAD, MERCURY SILVER, NITRO- PROS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV , 1982 05... 8.0 .320 JAN 1983 20... 10 .190 3 <100 1 1 10 .8 <1 <1 MAR 14... 11 .160 MAY 02... 7.1 .190 AUG 04... 9.7 .220 2 1 7 <.1 <1 <1 STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (WINOS) (DEG C) OCT, 08 1220 53 456 27.0 NOV, 17 1030 97 408 24.0 DEC, 20 0910 84 435 22.5 JAN, 03 1020 130 427 23.0 FEB, 01 0925 49 418 24.0 FEB, 16 0910 38 427 23.5 K = non-ideal count STREAMFL0W, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) MAR, 09 1345 31 436 26.0 APR, 08 0925 7.9 338 23.0 JUN, 20 1100 59 355 28.5 JUL. 07 1323 65 403 27.0 SEP, 06 1340 45 418 28.5 76 RIO CIBUCO BASIN 50039650 DRAINAGE DITCH BELOW WARNER LAMBERT LABORATORY NR SABANA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°27'17", long 66°21'09", 0.3 mile (0.5 km) northwest of Warner Lambert Laboratory, 0.6 mile (1.0 km) south of Sabana, and 1.1 miles (1.8 km) above confluence with Rio Cibuco. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1982 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN. OXYGEN COLI- SPE- DIS- DEMAND. FORM. STREAM- CIFIC SOLVED CHEM- FECAL, FLOW, CON- PH TUR- OXYGEN. (PER- ICAL 0.7 INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) NOV . 1982 16... 1115 4.9 419 6.5 26.0 16 .5 6 28 K7800 FEB . 1983 07... 1315 .00 500 6.7 25.0 7.0 .7 8 100 6500 MAR 24... 1000 .00 730 7.1 25.5 <1.0 .0 0 39 730 MAY 25... 1100 E19 195 6.8 29.0 4.8 .0 0 47 K170 AUG 24... 1010 .00 538 7.0 26.5 6.0 .0 0 58 4000 STREP- TOCOCCI HARD- MAGNE- FECAL. HARD- NESS. CALCIUM SIUM, SODIUM, KF AGAR NESS NONCAR- DIS- DIS- DIS- (COLS. (MG/L BONATE SOLVED SOLVED SOLVED PER AS (MG/L (MG/L (MG/L (MG/L DATE 100 ML) CAC03) CAC03) AS CA) AS MG) AS NA) SODIUM AD- SORP- TION RATIO POTAS- ALKA- SIUM, LINITY DIS- FIELD SOLVED (MG/L (MG/L AS AS K) CAC03) SULFATE DIS- SOLVED (MG/L AS 504) NOV , 1962 16... 4100 95 FEB . 1983 07... 320 130 9 40 7.0 42 1.7 2.4 120 7.0 MAR 24... 3200 150 MAY 25... 540 69 5 21 4.0 13 .7 2.4 64 12 AUG 24... 570 160 40 49 8.0 42 1.5 2.4 116 14 SOLIDS. SOLIDS, CHIC- FLUO- SILICA. SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- RIDE. RIDE. DIS- CONSTI- DIS- AT 105 GEN. GEN. GEN. GEN. DIS- DIS- SOLVED TUENTS, SOLVED DEG. Cr NITRITE NO2+NC3 AMMONIA ORGANIC SOLVED SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L DATE AS CL) AS F) 5IO2) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) NOV , 1982 16... 30 .020 <.10 .110 .79 FEB r 1983 07... 71 <.10 10 251 .00 13 .010 <.10 <.010 MAR 24... 5 <.010 <.10 .140 .46 MAY 25... 24 <.10 11 126 7 .010 <.10 .070 .93 AUG 24... 89 .10 9.7 284 .00 14 (.010 <.10 .110 .99 NITRO- CHRO- GEN,AM- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER. MONIA + PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL ORGANIC PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS N) AS P) AS AS) AS BA) AS CD) AS CR) AS P3) AS HG) AS SE) AS AG) NOV r 1982 16... .90 .030 FEB r 1983 07... 1.20 .180 2 100 1 7 14 .7 <1 <1 MAR 24... .60 .180 MAY 25... 1.00 .150 AUG 24... 1.10 .130 2 1 <1 10 <.1 <1 <1 K = non-ideal count E = estimate 77 RIO CIBUCO BASIN 50039700 DRAINAGE DITCH AT RIO CIBUCO BELOW CENTRAL SAN VICENTE, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°27'44", long 66°21'52", 60 ft (18 m), above confluence with Rio Cibuco, 984 ft (300 m) east of Central San Vicente, and 0.7 mi (1.2 km) west of Sabana. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1982 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL. FLOW. CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT.... (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV r 1982 16... 1315 22 737 6.9 26.5 16 3.0 37 23 K8300 2900 FEB • 1983 04... 1420 3.8 765 7.0 24.0 3.5 1.1 13 46 4600 280 MAR 24... 1200 3.4 1200 7.4. 27.0 2.7 3.0 38 34 270 700 MAY 23... 1345 E31 304 7.2 29.0 24 2.4 32 24 2500 3800 AUG 24... 1220 6.0 791 7.3 28.0 3.5 2.2 28 36 240 770 HARD- MAGNE- SODIUM PDTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SUM, SODIUM, AD- SIUM, UNITY SULFATE RIDE, RIDE, NESS NONCAR- DIS'.. DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV • 1982 16... FEa • 1983 04... 240 MAR 24... MAY 23... 140 AUG 24... 240 130 62 77 12 50 1.5 2.2 180 15 120 .10 170 30 45 6.6 24 .9 2.8 110 21 44 .10 75 77 12 61 1.8 2.4 167 19 130 .10 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- On- CONSTI- OIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) CMG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV • 1982 16... FEB • 1983 04... MAR 24... MAY 23... AUG 24... 44 .67 .230 .90 .490 .91 1.40 2.3 12 396 4.0 14 <.010 <.10 .130 .27 .40 16 .18 .020 .20 .180 .22 .40 .60 14 223 26 .15 .050 .20 .080 1.1 1.20 1.4 14 416 6.7 <1 <.010 <.10 .060 .54 .60 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELF- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UM (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV , 1982 16... 10 .090 FEB • 1983 04... .110 2 100 1 7 7 .4 <1 <1 MAR 24... 2.7 .060 MAY 23... 6.2 .100 AUG 24... .100 2 1 <1 5 <.1 <1 <1 K = non-ideal count E = estimate 78 RIO CIBUCO BASIN 50039750 RIO CIBUCO BELOW CENTRAL SAN VICENTE, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°27'47", long 66°21'53", at bridge on Highway 688, 1,000 ft (305 m) northeast of Central San Vicente, 0.8 mi (1.3 km) west of Sabana, and 1.3 mi (2.1 km) northwest of Warner Lambert Laboratory. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1982 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP•• SPE- On- DEMAND, FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL. FECAL, HARD- FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER AS DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CAC03) NOV , 1982 16... 1435 127 465 7.4 25.0 18 7.3 89 10 2700 670 FEB r 1983 04... 1300 45 454 7.5 24.0 8.2 7.4 88 24 K1300 440 180 MAR 24... 1300 28 470 7.8 27.5 1.1 7.0 39 15 510 590 MAY 23... 1300 398 281 7.8 27.0 110 5.6 70 10 4800 K10000 150 JUN 06... 1050 91 442 8.0 27.5 6.4 81 AUG 24... 1420 69 460 7.8 29.0 9.7 7.0 91 28 2900 550 190 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, NESS, CALCIUM SIUM, SODIUM. AD- SIUM, LINITY SULFATE RIDE, RIDE, BIS- NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- SOLVED BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS DATE CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) SI02) NOV , 1982 16... 140 FES , 1983 04... 24 58 9.5 20 .7 2.3 160 14 31 .10 17 MAR 24... 180 MAY 23... 20 49 6.6 15 .6 3.1 130 18 24 .10 15 JUN 06... 180 AUG 24... 26 62 9.3 21 .7 3.0 167 18 36 .20 20 SOLIDS. SOLIDS. NITRO- SUM OF SOLIDS. RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN.AM- CONSTI- DM'. AT 105 GEN, GEN, GEN, GEN, GEN, MCNIA + NITRO- TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL SOLVED PER FENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NITRO- GEN. TOTAL (MG/L AS NO3) NOV , 1982 16... 30 1.0 .070 1.1 .150 .45 .60 1.7 7.5 FEB , 1983 04... 248 30.2 9 1.3 .040 1.3 .040 .66 .70 2.0 8.9 MAR 24... 10 1.4 .120 1.5 .070 .13 .20 1.7 7.5 MAY 23... 209 224 100 .65 .050 .70 .100 .80 .90 1.6 7.1 JUN 06... AUG 24... 270 50.2 <1 .97 .030 1.0 .070 .53 .60 1.6 7.1 K = non-ideal count 79 RIO CIBUCO BASIN 50039750 RIO CIBUCO BELOW CENTRAL SAN VICENTE, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHRO- SEDI- BARIUM. CADMIUM MIUM. LEAD. MERCURY SILVER. MENT, PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL SEDI- DIS- PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM. RECOV- MENT, CHARGE. TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE SUS- SUS"' (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENDED PENDED DATE AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) (MG/L) (T/DAY) NOV r 1982 16... .100 FEB 1983 04... .200 2 100 1 4 2 .6 <1 4 MAR 24... .230 MAY 23... .120 290 311 JUN 06... AUG 24... .020 2 1 <1 7 <.1 <1 <1 CHLOR- DI- PCB, ALORIN. DANE. ODD, DOE, DOT. AZINON, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN r 1983 06... 1050 <.10 <.01 <.10 <.01 <.01 <.01 <.01 HEPTA- METH- DI- ENDO- HEPTA- CHLOR MALA- OXY- ELDRIN SULFAN. ENDRIN, ETHION, CHLOR, EPDXIDE LINDANE THION. CHLOR. TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN . 1983 06... <.01 <.01 <.01 <.01 <.01 <.01 <.01 <.01 (.01 NAPH- THA- METHYL METHYL LENES, PARA- TRI- PARA- POLY- PER- TOX'" TOTAL THION, THION, MIREX, THION, CHLOR. THANE APHENE, TRI- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL THION DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN r 1983 06... <.01 <.01 <.01 <.01 <.10 <.10 <1 <.01 81 DORADO .' OCEANO ATLANTIC 0 SAN JUAN • 150 CATAF40 EGA ALTA fiv Limestone Drainage boundaries indeterminate in limestone terrone 0458 L obos 0460 TOA ALTA Igneous and sedimentary rocks • AYAMON B Limestone Igneous and sedimentary rocks ‘,., -, —i N i \_, OROZ AL \_/- \ ."--,...1 L•go La Plata Map area 044=50 S NARANJ TO Rio Cibuco basin Drainage boundary BARR ANDO TAS Island divide CIDRA La Plat. 0430 Al ONITO • 38 •*­ R t'o Coorno basin DAVEY EXPLANATION A0460 SURFACE—WATER STATION AND NUMBER A0458 LOW—FLOW STATION AND NUMBER .• -0430 QUALITY—OF—WATER STATION AND NUMBER Rio Salinas (Niguo) basin • 38 WELL AND WELL NUMBER unnel to TRio Figure 16.--Rio de la Plata basin. 82 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 mi (0.6 km) northeast of Proyecto La Plata, and 2.5 mi (4.0 km) upstream from Rio UsabOn. DRAINAGE AREA.--54.8 sq mi (142 sq km), excludes 8.2 sq mi (21.1 sq 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. Altitude 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. The Puerto Rico Aqueduct and Sewer Authority operates a pumping plant about 5 mi (8 km) upstream which can divert as much as 23 cu ft/s (0.65 cu m/s) into Cidra Reservoir. AVERAGE DISCHARGE.--23 years (1961-83), 114 cu ft/s (3.228 cu m/s), 28.25 in/yr (718 mm/yr), 82,590 acre-ft/yr (102 cu hm/yr); median of yearly mean discharges, 88 cu ft/s (2.49 cu m/s), 63,800 acre-ft/yr (79 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 59,600 cu ft/s (1,688 cu m/s) Aug. 27, 1961, gage height, 32.21 ft (9.818 m), from rating curve extended above 7,000 cu ft/s (198 cu m/s) on basis of slope-area measurement; minimum daily, 2.6 cu ft/s (0.074 cu m/s) July 25, 1974. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 4,000 cu ft/s (113 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Nov. 20 1915 5,200 147 10.80 3.292 June 16 0815 *11,430 324 14.38 4.383 Mar. 12 1830 7,530 213 12.18 3.712 Aug. 21 1630 4,700 133 10.52 3.206 Apr. 21 0915 4,320 122 10.32 3.146 Minimum discharge, 7.9 cu ft/s (0.224 cu m/s) Apr. 14. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 204 154 469 96 21 20 12 33 15 49 78 49 2 122 70 225 59 21 16 13 31 12 82 146 68 3 79 56 153 42 21 14 13 36 11 75 91 65 4 61 47 134 44 20 14 12 32 11 357 68 41 5 50 43 115 87 20 14 13 31 13 796 71 36 6 47 40 93 90 20 13 13 28 15 468 65 34 7 44 49 93 83 20 13 12 30 18 481 57 30 8 41 36 72 59 21 14 11 28 14 240 48 27 9 39 35 61 158 20 20 9.8 24 14 141 41 25 10 35 34 55 80 23 18 9.4 23 17 104 38 25 11 30 41 51 49 24 12 9.7 17 14 85 35 24 12 30 122 48 59 24 1520 10 15 15 78 36 25 13 114 148 46 49 23 293 9.7 21 16 74 63 25 14 132 93 45 39 24 77 9.0 192 16 61 35 22 15 50 65 175 38 25 47 9.7 115 61 52 31 22 16 39 55 151 38 22 36 13 49 2920 52 30 27 17 37 51 71 35 22 29 18 32 585 51 214 25 18 34 46 55 30 23 26 132 162 988 54 212 26 19 32 92 49 28 21 23 53 157 355 50 92 22 20 171 850 75 28 20 21 45 235 175 42 63 23 21 150 410 81 27 28 20 936 66 118 45 884 294 22 125 161 53 27 33 19 134 53 88 41 358 209 23 140 158 48 26 23 19 56 34 72 43 129 60 24 119 117 46 25 22 17 38 50 60 348 78 51 25 80 96 45 25 23 17 28 64 54 114 61 42 26 65 84 63 34 22 17 23 39 50 74 58 55 27 54 240 125 30 21 15 207 27 51 57 52 37 28 47 251 79 24 18 14 198 22 65 49 341 31 29 48 154 66 23 --- 15 108 19 47 213 102 27 30 44 588 51 25 13 46 19 45 208 67 26 31 59 --- 302 27 11 --- 20 --- 102 60 --- TOTAL 2322 4385 3185 1484 625 2417 2201.3 1704 5935 4686 3704 1473 MEAN 74.9 146 103 47.9 22.3 78.0 73.4 55.0 198 151 119 49.1 MAX 204 850 469 158 33 1520 936 235 2920 796 884 294 MIN 30 34 45 23 18 11 9.0 15 11 41 30 22 CFSM 1.37 2.66 1.88 .87 .41 1.42 1.34 1.00 3.61 2.76 2.17 .90 IN. 1.58 2.98 2.16 1.01 .42 1.64 1.49 1.16 4.03 3.18 2.51 1.00 AC-FT 4610 8700 6320 2940 1240 4790 4370 3380 11770 9290 7350 2920 CAL YR 1982 TOTAL 28888.4 MEAN 79.1 MAX 3000 MIN 5.7 CFSM 1.44 IN 19.61 AC-FT 57300 WTR YR 1983 TOTAL 34121.3 MEAN 93.5 MAX 2920 MIN 9.0 CFSM 1.71 IN 23.16 AC-FT 67680 83 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 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM-. FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN. (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100'ML) NOV , 1982 15... 1220 62 234 7.2 25.0 32 8.4 105 18 2800 550 JAN . 1983 12... 1305 51 318 7.6 24.0 15 9.0 110 29 780 240 MAR 08... 1345 15 485 8.4 25.5 4.9 10.0 127 19 K220 1300 MAY 05... 1045 32 363 8.2 26.0 9.5 8.4 107 35 660 750 AUG 12... 1115 33 333 8.4 29.0 2.2 9.6 129 29 K160 160 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS FIELD DIS- DIS- DIS (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/1 AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV . 1982 15... 71 JAN . 1983 12... 110 3 27 11 22 .9 1.6 110 13 21 .10 MAR 08... 190 MAY 05... 160 5 39 14 31 1.1 2.7 150 20 30 .30 AUG 12... 120 0 30 12 26 1.0 1.6 126 14 24 .20 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN.AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. C. NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN. (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 15... 20 .92 .080 1.0 .080 .52 .60 1.6 JAN , 1983 12... 23 185 25.2 14 1.2 .030 1.2 .040 .26 .30 1.5 MAR 08... 10 1.1 .020 1.1 .030 .77 .80 1.9 MAY 05... 27 254 21.9 6 1.9 .080 2.0 .020 .38 .40 2.4 AUG 12... 25 208 18.6 <1 1.2 .030 1.2 .020 .48 .50 1.7 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV 1982 15... 7.1 .270 JAN , 1983 12... 6.6 .250 2 <100 2 14 5 <.1 3 <1 MAR 08... 8.4 .490 MAY 05... 11 .510 AUG 12... 7.5 .420 2 100 1 <1 3 <.1 <1 <1 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS OUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) OCT, 04 1100 61 237 27.0 JUN. 13 1400 14 483 DEC, 14 1155 43 367 24.0 JUL, 11 1340 85 269 30.0 FEB, 07 1325 21 450 25.5 SEP. 14 1325 22 400 31.0 APR. 04 1440 13 532 30.0 K = non-ideal count 84 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 mi (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 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, HARD- FLOW. CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS INSTAN- DUCT- (STAND- TEMPER- BID- °IS- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER AS DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CAC03) NOV r 1982 10... 1040 59 337 7.8 26.0 3.6 10.1 127 14 3600 1600 JAN , 1983 11... 1150 126 336 7.7 22.5 25 3.6 102 18 4000 660 120 MAR 28... 1120 38 436 8.4 25.5 <1.0 9.8 122 19 K1300 370 MAY 12... 0945 66 304 8.4 26.5 13 8.8 112 16 K1800 3000 130 AUG 19... 1100 158 243 8.0 27.0 37 3.6 110 83 26000 K1100 83 HARD- NESS, NONCAR- BONATE (MG/L DATE CAC03) CALCIUM DI S- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM, DIS- SOLVED (MG/L AS NA) SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, AD- SIUM, LINITY SULFATE RIDE, RIDE, DIS- SORP- DIS- FIELD OIS- DIS- DIS- SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS AS K) CAC03) AS SO4) AS CL) AS F) SI02) NOV , 1982 10... 120 JAN , 1983 11... 22 29 12 25 1.0 2.2 100 13 26 .10 26 MAR 28... 170 MAY 12... 0 32 13 23 .9 3.1 140 19 26 .20 24 AUG 19... 4 20 8.0 18 .9 2.0 79 11 21 .10 21 SOLIDS, SOLIDS, NITRO- SUN OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- NITRO-• TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEN, DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) DAY) (MG/L) AS N) AS N) 4S N) AS N) AS N) AS N) AS N) AS NO3) NOV , 1932 10... 6 .78 .020 .80 .050 .75 .80 1.6 7.1 JAN , 1983 11... 193 65.7 14 .30 .100 .40 .250 4.6 4.80 5.2 23 MAR 28... 7 .56 .040 .60 .040 .26 .30 .90 4.0 MAY 12... 224 40.0 14 .38 .020 .90 .020 .28 .30 1.2 5.3 AUG 19... 148 63.3 25 .66 .040 .70 .010 .69 .70 1.4 6.2 CHRO- SEDI- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, MENT, PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL SEDI- DIS- PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- MENT, CHARGE, TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE SUS- SUS- (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENDED PENDED DATE AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) (MG/L) (T/DAY) NOV r 1982 10... .270 4- JAN , 1983 11... .360 2 100 2 <1 5 <.1 <1 <1 MAR 28... .340 MAY 12... .360 AUG 19... .240 2 100 1 2 3 <.1 <1 <1 K = non-ideal count 99 18 85 RIO DE LA PLATA BASIN 50044850 RIO GUADIANA NEAR NARANJITO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°18'39", long 66°13'28", at steel-cross-bridge 0.8 mi (1.3 km) northwest of Highway 164, 1.2 mi (1.9 km) upstream from mouth and about 2.0 mi (3.2 km) northeast of Naranjito plaza. DRAINAGE AREA.--4.0 sq mi (10.3 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, HARD- FLOM, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS INSTAN* DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR* LEVEL) (COLS./ PER AS DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CAC03) NOV r 1982 10... 1340 3.9 336 7.8 26.5 2.6 8.2 103 27 900 1200 JAN , 1983 11... 1450 11 320 8.1 25.0 1.6 9.0 110 16 K9300 450 130 MAR 28... 1335 5.3 318 8.6 26.0 1.4 9.0 111 17 K1200 660 MAY 12... 1245 30 253 8.0 27.5 24 8.0 102 22 K18000 3600 98 AUG 19... 1345 7.6 319 8.0 30.0 2.3 8.2 109 20 5800 K1100 130 HARD- MAGNE- SODIUM POTAS- ALKA- MO- FLUO- SILICA, NESS, CALCIUM SIUM, SODIUM, AD- SIUM, LENITY SULFATE RIDE, RIDE, DIS- NONCAR- DIS- DES- Ens- SORP- DES- FIELD DIS- DIS- DIS- SOLVED BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS DATE CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS 504) AS CL) AS F) SI02) NOV , 1982 10... 120 JAN . 1983 11... 24 29 15 18 .7 1.7 110 16 18 .20 29 MAR 28... 120 MAY 12... 21 21 11 13 .6 2.8 77 21 20 .10 23 AUG 19... 21 30 14 16 .6 2.5 112 18 21 .20 27 SOLIDS, SOLIDS, NITRO- SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN.AM- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- NITRO- TUENTS, SOLVED DEG. C. NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEN, DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) NOV e 1982 10... -- 8 1.6 .010 1.6 .030 .57 .60 2.2 9.7 JAN r 1983 11... 193 5.6 4 1.7 .010 1.7 .020 .98 1.00 2.7 12 MAR 28... 16 1.3 .030 1.3 .010 .29 .30 1.6 7.1 MAY 12... 158 12.8 22 1.9 .020 1.9 .030 .27 .30 2.2 9.7 AUG 19... 196 4.0 1 <.010 1.6 <.010 .30 1.9 8.4 CHRO- SEDI- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, MENT, PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL SEDI- DIS- PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- MENT, CHARGE, TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE SUS- SUS- (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENDED PENDED DATE AS P) AS AS) AS 8A) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) (MG/L) (T/DAY) NOV , 1982 10... .320 JAN , 1983 11... .510 1 100 1 <1 5 <.1 <1 <1 MAR 28... .330 MAY 12... .160 AUG 19... .320 2 100 1 1 2 <.1 <1 <1 K = non-ideal count 82 6.6 86 RIO DE LA PLATA BASIN 50046000 RIO DE LA PLATA AT TOA ALTA, PR LOCATION.--Lat 18°23'50", long 66°15'17", Hydrologic Unit 21010005, on left bank, at upstream side of bridge on Highway 165, 800 ft (244 m) downstream from Rio Lajas, and 0.6 mi (1.0 km) northwest of Toa Alta, 10 mi (16 km) downstream from Puerto Rico Aqueduct and Sewer Authority reservoir. DRAINAGE AREA.--200 sq mi (518 sq km), excludes 8.2 sq km (21.2 sq km) upstream from Lago Carite, flow from which is diverted to Rio Guamani. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--November 1959 (measurement only), January 1960 to current year. GAGE.--Water-stage recorder. Datum of gage is 8.55 ft (2.606 m) above mean sea level (levels by Puerto Rico Department of Public Works). Prior to Feb. 25, 1960, wire-weight gage at same site and datum. REMARKS.--Records fair. Regulation at all stages by Puerto Rico Aqueduct and Sewer Authority reservoir upstream from gage. AVERAGE DISCHARGE.--23 years (1961-83), 276 cu ft/s (7.816 cu m/s), 18.74 in/yr (476 mm/yr), 200,000 acre-ft/yr (247 cu hm/yr); median of yearly mean discharges 220 cu ft/s (6.23 cu m/s), 159,000 acre-ft/yr (196 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 95,500 cu ft/s (2,704 cu m/sp) Sep. 6, 1960, gage height, 36.35 ft (11.079 m), from floodmark, from rating curve extended above 12,000 cu ft/s (340 cu m/s) on basis of contracted-opening measurement of peak flow; minimum, 3.1 cu ft/s (0.088 cu m/s) Mar. 12, 1974, gage height, 6.51 ft (1.984 m). EXTREMES OUTSIDE PERIOD OF RECORD.--Approximate discharges and elevations to gage datum of major floods, as pointed out by local resi- dents are as follows: Sept. 13, 1928, 120,000 cu ft/s (3,400 cu m/s), gage height, 37.4 ft (11.4 m); June 16, 1943, 82,000 cu ft/s (2,320 cu m/s), gage height, 34.4 ft (10.48 m). EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 6,000 cu ft/s (170 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Apr. 21 1415 7,500 212 17.41 5.306 Apr. 22 2145 *16,700 473 22.04 6.718 Minimum discharge, 6.9 cu ft/s (0.195 cu m/s) Apr. 11-13. DISCHARGE, IN CUBIC FEET PER SECONDS WATER YEAR OCTOBER 1982 TC SEPTEMBER 1 983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 276 31 898 766 25 12 7.7 111 58 49 31 35 2 388 51 513 411 24 12 7.7 79 51 54 30 32 3 178 65 264 243 23 12 8.0 78 47 54 29 35 4 96 60 200 193 23 11 9.2 56 46 116 28 33 5 59 55 167 165 20 11 8.1 50 46 725 108 31 6 43 48 140 161 19 11 9.4 46 42 706 78 30 7 34 41 94 175 18 11 9.0 42 44 489 64 130 8 27 36 45 174 17 10 8.3 38 46 534 53 140 9 22 32 32 160 16 10 7.5 39 55 58 46 60 10 21 37 29 205 16 10 7.2 37 45 52 40 45 11 19 95 29 180 16 10 7.1 120 37 71 36 40 12 18 115 29 147 15 243 6.9 473 32 113 983 42 13 19 1010 31 126 15 1120 9.0 1230 31 60 509 56 14 70 559 32 103 15 390 9.7 1250 30 50 333 50 15 152 240 76 99 15 183 9.1 1010 29 47 178 85 16 79 127 277 96 15 99 8.0 548 1610 43 313 47 17 43 132 235 92 14 57 8.3 304 1420 43 229 41 18 30 88 167 103 14 26 30 487 1390 55 308 42 19 28 61 117 83 14 16 19 1770 1120 47 348 47 20 31 41 96 62 13 13 54 2100 584 42 258 49 21 65 534 329 64 13 11 4720 883 322 38 596 619 22 127 520 157 44 13 10 3800 760 133 36 1460 285 23 128 197 119 39 13 9.9 2020 530 71 35 59 450 24 100 128 99 41 13 9.5 762 314 57 37 50 489 25 113 99 120 39 12 8.9 303 238 46 38 46 233 26 59 111 581 37 12 8.7 160 296 38 34 48 163 27 45 120 2090 34 12 8.4 101 317 36 32 51 126 28 38 513 1110 31 12 9.6 144 190 40 32 143 100 29 34 501 677 23 --- 8.7 241 128 42 32 49 82 30 30 544 348 28 8.2 136 93 42 37 42 72 31 31 --- 277 26 7.9 --- 73 --- 34 38 --- TOTAL 2403 6191 9428 4165 447 2367.8 12680.2 13590 7590 3793 6584 3694 MEAN 77.5 206 304 134 16.0 76.4 423 442 253 122 212 123 MAX 388 1010 2090 766 25 1120 4720 2100 1610 725 1460 619 MIN 18 31 29 26 12 7.9 6.9 37 29 32 28 30 CFSM .39 1.03 1.52 .67 .08 .38 2.12 2.21 1.27 .61 1.06 .62 IN. .45 1.15 1.75 .77 .08 .44 2.36 2.55 1.41 .71 1.22 .69 AC-FT 4770 12280 18700 8260 887 4700 25150 27150 15050 7520 13060 7330 CAL YR 1982 TOTAL 55493.0 MEAN 152 MAX 5390 MIN 12 CFSM .76 IN 10.32 AC-FT 110100 WTR YR 1983 TOTAL 73033.0 MEAN 200 MAX 4720 MIN 6.9 CFSM 1.00 IN 13.58 AC-FT 144900 87 RIO DE LA PLATA BASIN 50046000 RIO DE LA PLATA AT TOA ALTA, PR--Continued (National stream-quality accounting network station) WATER-QUALITY RECORDS LOCATION.--Samples collected at bridge on Highway 2, 1.2 mi (1.9 km) downstream from discharge station. PERIOD OF RECORD.--Water years 1958 to current year WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, COLI- STREP- SPE- DIS- FORM, TOCOCCI HARD STREAM CIFIC SOLVED FECAL, FECAL, HARD- NESS, FLOW, CON- PH TUR- OXYGEN, (PER- 0.7 KF AGAR NESS NONCAR- INSTAN- DUCT- (STAND- TEMPER- BID- DIS CENT UM-MF (COLS. (MG/L BONATE TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- (COLS.! PER AS (MG/L DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) 100 ML) 100 ML) CAC03) CAC03) OCT , 1982 12... 1225 18 458 7.6 30.0 3.5 8.0 108 K60 <10 170 5 DEC 01... 1400 864 255 6.8 25.0 17 6.6 80 K1400 K200 92 8 FEB , 1983 04... 0950 19 474 7.0 24.0 1.2 9.5 114 200 400 200 144 APR 05... 1150 7.6 608 7.0 26.5 2.4 6.0 75 K100 K200 230 12 JUN 13... 1130 31 495 8.3 30.5 3.4 9.0 120 K250 K23 180 15 AUG 05... 1215 113 330 7.4 29.0 4.5 6.0 78 3400 130 130 6 SOLIDS, MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, RESIDUE CALCIUM SIUM, SODIUM, AD- SIUM, LINITT SULFATE RIDE RIDE, Dn.". AT 180 DIS- DIS- DIS- SORP- DIS- FIELD DIS- ors-1 DIS- SOLVED DEG. C SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L DIS- (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS SOLVED DATE AS CA) AS MG) AS NA) AS K) CAC03) AS 504) AS CO AS F) SI02) (MG/L) OCT , 1982 12... 50 12 24 .8 2.2 170 17 36 .20 21 276 DEC 01... 23 8.4 17 .8 3.0 34 13 15 .10 20 165 FEB , 1983 04... 57 13 26 .8 1.5 52 17 36 .20 20 272 APR 05... 68 15 33 1.0 2.4 220 16 49 .20 22 333 JUN 13... 54 12 24 .8 2.5 170 24 36 .20 17 272 AUG 05... 34 10 18 .7 3.5 120 13 23 .10 21 230 SOLIDS, NITRO- NITRO- NITRO- NITRO- PHOS- PHOS- SUM OF SOLIDS, GEN, GEN, GEN, GEN,AM- PROS- PHORUS, PRATE, CONSTI- DIS- NO2+NO3 AMMONIA AMMONIA MONIA + PHOS- PROS- PHORUS, ORTHO, ORTHO, TUENTS, SOLVED DIS- DIS- DIS- ORGANIC PHORUS, PHORUS DIS- DIS- DIS- On- (TONS SOLVED SOLVED SOLVED TOTAL TOTAL TOTAL SOLVED SOLVED SOLVED SOLVED PER (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) DAY) AS N) AS N) AS NH4) AS N) AS P) AS PO4) AS P) AS P) AS PO4) OCT , 1982 12... 265 13.2 .14 .080 .10 .50 .130 .40 .110 .090 .28 DEC 01... 151 385 .20 .240 .31 .70 .270 .83 .180 .200 .61 FEB , 1983 4... 202 13.9 -h APR 5... 338 6.8 <.10 .060 .08 .20 .120 .37 .160 .120 .37 JUN 13... 272 22.8 <.10 .010 .01 .80 .130 .40 .080 .050 .15 AUG 05... 196 70.0 .30 .220 .28 .60 .190 .58 .170 .150 .46 ALUM- BERYL- CHRO- INUM, ARSENIC BARIUM, LIUM, CADMIUM MIUM, COBALT, COPPER1, IRON, LEAD, LITHIUM DIS- DIS- On- DIS- DIS- DIS- DIS- OIS- DIS- DIS- DIS- SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVE SOLVED SOLVED SOLVED (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS AL) AS AS) AS BA) AS BE) AS CD) AS CR) AS CO) AS CU AS FE) AS PB) AS LI) OCT , 1982 12... 2 67 <1 <1 <1 <3 7 <1 <4 DEC 01... FEB , 1983 -7 4... 10 2 61 <1 <1 3 <3 6 15 3 <4 APR 5... 4 JUN 13... 10 2 67 1 1 <1 3 13 1 4 AUG 05... 90 3 87 <1 <1 <1 <3 42 1 5 K = non-ideal count RIO DE LA PLATA BASIN 88 50046000 RIO DE LA PLATA AT TOA ALTA, PR - -Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 SEDI- MANGA MOLTS- SELF- STRON- VANA- MENT, NESE. MERCURY DENUMp NICKEL, NIUM, SILVER, TIUM, DIUM, ZINC. SEDI- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- MEW'', CHARGE, SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SUS- SUS (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENDED PENDED DATE AS MN) AS HG) AS NO) AS NI) AS SE) AS AG) AS SR) AS V) AS ZN) (MG/L) (T/DAY) OCT , 1982 12... 88 .1 10 2 <1 <1 240 <6.0 6 3 .15 DEC 01... 24 56 FEB . 1983 04... 69 .6 <10 4 <1 <1 230 <6.0 8 11 .56 APR 05... 48 .98 JUN 13... 130 1.0 10 <1 <1 <1 250 6.0 4 4 .33 AUG 05... 67 .2 <10 2 <1 <1 150 8.0 <3 12 3.7 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, 15 0950 265 285 26.0 MAY, 04 0843 58 423 27.5 JAN, 18 0940 105 343 26.0 SEP. 13 1456 57 410 29.5 MAR. 11 1445 10 475 26.0 CHLOR- DI- DI- ENDO- PCB, ALDRIN, DANE, DOD, DOE, DOT, AZINON. ELDRIN SULFAN, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN . 1983 13... 1130 <.10 <.01 <.10 <.01 <.01 <.01 .01 <.01 <.01 HEPTA- METH- METHYL METHYL HEPTA- CHLOR MALA- OXY- PARA- TRI- ENDRINs ETHION, CHLOR. EPDXIDE LINOANE THION, CHLOR, THION. THION, MIREX. TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN . 1983 13... <.01 .01 <.01 <.01 <.01 .01 (.01 .01 .01 (.01 NAPH- THA- LENES, PARA- POLY- PER- TOX- TOTAL THION. CHLOR. THANE APHENE, TRI- 2,4-D, 2.4.5-T 2, 4-DP SILVEX, TOTAL TOTAL TOTAL TOTAL THION TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1983 13... .01 <.10 <.10 <1 .01 .01 (.01 <.01 <.01 SED. SUSP. STREAM- SERI- SIEVE FLOW. MENT, DIAM. INSTAN- SUS- X FINER TIME TANEOUS PENDED THAN DATE (CFS) (MGM .062 MM OCT . 1982 12... 1225 18 3 100 DEC 01... 1400 864 24 79 FEB , 1983 4... 0950 19 11 100 APR 5... 1150 7.6 48 85 JUN 13... 1130 31 4 75 AUG 05... 1215 113 12 100 BED MAT. STREAM- SIEVE FLOW. DIAM. INSTAN- X FINER TIME TANEOUS THAN DATE (CFS) .062 MM AUG . 1983 05... 1410 E112 1 E = estimate 89 OCEANO ATLANTIC° SAN JUAN 049920 CATA 0 in limestone terrane 660 BAYAM 47525 .475. R Mies GUA NABO LWL, TRUJILLO ALTO E Rio Grande de Loiza bosin CIDRA EXPLANTION A 0490 LOW-FLOW STATION AND NUMBER 0488 QUALITY-OF-WATER STATION AND NUMBER 42 WELL AND WELL NUMBER Map area .AGUADILLA SAN JUAN FAJARDO. MAYAGUEZ Figure 17.--Rio Hondo, Rio de Bayamon. and Rio Puerto Nuevo basins. 90 RIO HONDO BASIN 50047530 RIO HONDO AT FLOOD CHANNEL NEAR CATARO,PR (Formerly published as 50048530 Rio Hondo below Rio Hondo nr Bayam6n, PR) WATER-QUALITY RECORDS LOCATION.--Lat 18°26'13", long 66°09'36", at Rio Hondo Channel, 800 ft (245 m) below junction with Rio Hondo, 0.9 mi (1.5 km) downstream from bridge on de Diego Expressway and 1.1 mi (1.8 km) above mouth. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 DATE SPE- CIFIC CON- PH DUCT- (STAND- TIME ANCE ARD (UMHOS) UNITS) TEMPER- ATURE (DEG C) TUR- OXYGEN, 3ID- DES- ITY SOLVED (NTU) (MG/L) OXYGEN. OXYGEN COLE- STREP- DIS- DEMAND, FORM, TOCOCCI SOLVED CHEM- FECAL, FECAL. (PER- ICAL 0.7 KF AGAR CENT (HIGH UM-MF (COLS. SATUR- LEVEL) (COLS./ PER ATION) (MG/L) 100 ML) 100 ML) HARD- NESS (MG/L AS CAC03) NOV 1982 24... 1315 17500 7.5 28.0 4.0 .0 0 710 34000 K450 *24... 1325 36000 7.9 27.0 25 2.8 40 2300 K12000 2000 FEB , 1933 08... 1400 31200 8.5 30.5 8.0 730 K91000 K60 3900 MAR 25... 1425 35200 3,5 31.5 5.5 14.2 218 1500 4600 <100 MAY 24... 1455 13700 8.8 33.0 5.0 24.6 337 3000 K730 2200 AUG 25... 1315 11000 8.4 31.0 3.2 20.0 278 340 49000 1200 HARD- NESS, CALCIUM NONCAR- DES- SONATE SOLVED (MG/L (MG/L DATE CAC03) AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM. DIS- SOLVED (MG/L AS NA) SODIUM AD- SORP- TION RATIO POTAS- ALKA- SIUM, LENITY DIS- FIELD SOLVED (MG/L (MG/L AS AS K) CAC03) SULFATE DES- SOLVED (MG/L AS SO4) CHLO- FLUO- RIDE, RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CL) AS F) NOV , 1982 24... 24... FEB .1983 08... 3710 150 850 7200 MAR 25... MAY 24... 2100 150 440 3300 AUG 25... 1030 110 220 1900 130 5800 120 16000 51 250 170 1800 14000 170 14000 31 140 120 300 6300 24 68 156 470 3400 .60 .04 .30 SOLIDS, SOLIDS, SILICA, SUM OF RESIDUE NITRO- NITRO- NITRO- DIS- CONSTI- AT 105 GEN, GEN, GEN, SOLVED TUENTS, DEG. Cr NITRATE NITRITE NO2+NO3 (MG/L On- SUS- TOTAL TOTAL TOTAL AS SOLVE() PENDED (MG/L (MG/L (MG/L DATE SI02) (MG/L) CMG/L) AS N) AS N) AS N) NITRO- NITRO- NITRO- GEN,AM- GEN, GEN. MONIA + NITRO- AMMONIA ORGANIC ORGANIC GEN, TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L (MG/L AS N) AS N) AS N) AS N) NOV r 1982 24... 24... FEB • 1983 08... MAR 25... MAY 24... AUG 25... 8 .13 .070 .20 45 .05 .050 .10 .1 24400 49 .05 .050 .10 72 .07 .030 .10 4.6 11200 36 .15 .050 .20 13 6270 12 .00 .120 .10 2.80 .00 2.80 3.0 .750 .05 .80 .90 3.20 2.2 5.40 5.5 2.00 2.0 4.00 4.1 .24 1.2 1.40 1.6 1.80 1.5 3.30 3.4 NITRO- GEN, TOTAL (MG/L DATE AS NO3) PHOS- PHORUS, TOTAL (MG/L AS P) CHRO- BARIUM, CADMIUM MIUM, TOTAL TOTAL TOTAL ARSENIC RECOV- RECOV- RECOV- TOTAL ERABLE ERABLE ERA3LE (UG/L (UG/L (UG/L (UG/L AS AS) AS BA) AS CD) AS CR) LEAD, MERCURY SILVER, TOTAL TOTAL SELE- TOTAL RECOV- RECOV- NIUM, RECOV- ERABLE ERABLE TOTAL ERABLE (UG/L (UG/L (UG/L (UG/L AS P8) AS HG) AS SE) AS AG) NOV • 1982 24... 13 .660 24... 4.0 .200 FEB , 1983 08... 24 1.90 4 200 1 13 5 1.7 <1 1 MAR 25... 13 1.30 MAY 24... 7.1 .310 AUG 25... 15 .130 4 1 9 8 <.1 <1 <1 * = sampling depth seven (7) feet K = non-ideal count CENT 91 RIO DE BAYAMON BASIN 50047600 RIO DE BAYAMON NEAR AGUAS BUENAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°14'39", long 66°08'39", at bridge on Highway 156, and 2.9 mi (4.7 kmj 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 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP­ SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN, (PER-ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV . 1982 23... 1015 29 228 7.2 22.0 8.5 8.0 94 150 400 690 JAN e 1983 18... 1115 31 246 7.6 21.0 2.9 9.0 104 28 480 530 MAR 17... 1425 27 244 8.2 27.0 3.3 8.0 105 17 290 2000 MAY 05... 1350 22 234 8.6 26.5 3.1 9.0 116 26 220 490 AUG 12... 1440 28 226 8.4 27.0 3.3 8.0 103 70 370 750 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CACO3) CAC03) AS CA) AS MG) AS NA) AS K) ¶AC03) AS SO4) AS CL) AS F) NOV , 1952 23... 75 JAN • 1983 18... 87 3 19 9.7 16 .8 2.9 84 9.0 16 .10 MAR 17... 93 MAY 05... 94 0 21 10 19 .9 2.4 97 10 18 .10 AUG 12... 85 0 19 9.2 16 .8 1.9 92 9.4 16 .10 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM­ DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL tOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV 1982 23... 6 .69 .010 .70 .030 .27 .30 1.0 JAN 1983 18... 23 146 12.1 2 <.010 .50 .020 .48 .50 1.0 MAR 17... <1 <.010 .30 .010 .49 .50 .80 MAY 05... 24 163 9.7 <1 <.010 .20 <.010 .20 .40 AUG 12... 23 150 11.4 <1 <.010 .20 .010 .19 .20 .40 CHRO- BARIUM, CADMIUM MIUM, LEAD MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERA8LE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PS) AS HG) AS SE) AS AG) NOV • 1982 23... 4.4 .080 JAN e 1983 18... 4.4 .050 2 <100 1 <1 .1 <1 <1 MAR 17... 3.5 .040 MAY 05... 1.8 .040 AUG 12... 1.8 .050 2 100 1 <1 3 <.1 <1 <1 SPE- STREAM- CIFIC FLON, CON- PH INSTAN- DUCT- (STAND- TEMPER- TIME TANEOUS ANCE ARD ATURE DATE (CFS) (UMHOS) UNITS) (DEG C) NOV • 1982 04... 1350 16 430 7.2 27.5 JAN , 1983 13... 1225 23 412 7.1 24.0 MAR 18... 1210 15 497 7.5 28.5 MAY 17... 1230 30 340 7.3 28.0 AUG 18... 1240 33 362 7.7 28.0 HARD- NESS (MG/L AS DATE CAC03) HARD- NESS, NONCAR- 8ONATE (MG/L CAC03) CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM. DIS- SOLVED (MG/L AS MG) SODIUM, DIS- SOLVED (MG/L AS NA) TUR- BID- ITT (NTU) 4.0 1.3 1.8 5.4 26 SODIUM AD- SORP- TION RATIO 92 RIO DE BAYAMON BASIN 50047990 RIO GUAYNABO NEAR BAYAMON, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°22'32", long 66°07'59", 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, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, DIS- SOLVED (MG/L) OXYGEN. OXYGEN COLI- STREP- DIS- DEMAND, FORM, TOCOCCI SOLVED CHEM- FECAL. FECAL. (PER- ICAL 0.7 KF AGAR CENT (HIGH UM-MF (COLS. SATUR- LEVEL) (COLS./ PER ATION) CMG/L) 100 ML) 100 ML) 3.6 46 26 34000 830 3.4 40 K13000 K270 .0 0 59 180000 5400 3.9 50 56 4200 K1500 5.2 66 36 K90000 4200 POTAS- ALKA- CHLO- FLUO- SIUM, LINITY SULFATE RIDE. RIDE. DIS- FIELD OH- DIS- DIS- SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L AS (MG/L (MG/L (MG/L AS K) CAC03) AS SO4) AS CL) AS F) NOV P 1982 04... JAN • 1983 13... 140 MAR 18... MAY 17... 150 AUG 13... 130 140 0 38 12 25 .9 3.8 150 15 35 .10 170 10 40 12 29 1.1 3.8 140 25 35 .20 6 34 9.9 22 .9 3.4 120 21 27 .20 SOLIDS. SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 ;EN, GEN, GEN, GEN, GEN, MONIA + SOLVED TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) NITRO- GEN, TOTAL (MG/L AS N) NOV • 1992 04... JAN • 1983 13... MAR 18... MAY 17... AUG 18... 18 .07 .030 .10 2.70 .80 3.50 3.6 8 .27 .030 .30 1.50 .90 2.40 2.7 <1 .020 <.10 4.00 1.5 5.50 8 .35 .050 .40 1.30 .00 1.30 1.7 32 .42 .080 .50 .950 .95 1.90 2.4 30 249 15.7 23 257 20.3 26 215 19.2 NITRO- GEN, TOTAL (MG/L DATE AS NO3) PHOS- PHORUS. TOTAL (MG/L AS P) CHRO- BARIUM. CADMIUM MIUM, LEAD, MERCURY TOTAL TOTAL TOTAL TOTAL TOTAL ARSENIC RECOV- RECOV-. RECOV- RECOV- RECOV- TOTAL ERA3LE ERABLE ERABLE ERABLE ERABLE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS AS) AS BA) AS CD) AS CR) AS P3) AS HG) SELE- NIUM. TOTAL (UG/L AS SE) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) NOV • 1982 04... 16 .900 JAN • 1983 13... 12 .830 MAR 18... 2.30 MAY 17... 7.5 .490 AUG 18... 11 .300 K = non-ideal count 2 100 1 9 3 .3 <1 <1 4 200 1 2 3 <.1 <1 <1 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 Highway 2, and 3.2 mi (5.1 km) above mouth. (Revised) DRAINAGE AREA.--71.9 sq mi (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 1982 TO SEPTEMBER 1983 OXY EN. OXYGEN CDLI- STREP- SPE- 0 S- DEMAND. FORM. TOCOCCI STREAM- CIFIC SO VED CHEM- FECAL, FECAL, FLOW. CON- PH TUR- OXYGEN. (P R- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- 9ID- DIS- C NT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SA UR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) AT ON) (MG/L) 100 ML) 100 ML) NOV • 1982 04... 0950 92 355 7.1 25.5 17 4.4 54 19 1(90000 5300 JAN r 1983 13... 0915 53 400 6.9 23.0 1.5 3.6 42 45000 2100 MAR 18... 0955 28 470 7.6 27.5 1.3 3.4 43 28 52000 5700 MAY 17... 0905 66 306 7.4 26.0 9.5 4.2 52 76 58000 6700 JUN 06... 1315 44 446 7.5 29.0 6.4 83 AUG 18... 0925 116 304 7.6 26.0 71 5.6 69 36 60000 39000 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS. CALCIUM SIUM, SODIUM, AD- SIUM, LIN TY SULFATE RIDE, RIDE. NESS NONCAR- ors- ors- US- SORP- DIS- FI LD On- DIS- DIS- (MG/L SONATE SOLVED SOLVED SOLVED TION SOLVED (M /L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L A (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CA 03) AS SO4) AS CL) AS F) NOV • 1982 04... JAN • 1983 13... 140 MAR 18... MAY 17... 150 JUN 06... AUG 18... 110 120 0 36 12 24 .9 3.7 140 17 32 .20 170 9 38 13 26 1.0 3.4 140 24 27 .20 160 9 29 9.4 18 .8 3.1 102 16 21 .20 SOLIDS. SOLIDS. NITRO- SILICA. SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GENrAM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMM NIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TO AL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (M IL (MG/i (MG/L (MG/L DATE 5IO2) CMG/L) OAT) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOY , 1982 04... 40 .33 .070 .40 110 .50 1.60 2.0 JAN r 1983 13... 29 238 34.3 22 .44 .160 .60 1.50 4.1 5.60 6.2 MAR 18... <1 .020 <.10 3.80 .60 4.40 MAY 17... 27 243 43.2 12 .51 .090 .60 .890 .31 1.20 1.8 JUN 06... AUG 18... 23 181 56.6 <1 .40 .100 .50 .420 .78 1.20 1.7 K = non-ideal count 93 RIO DE BAYAMON BASIN 50048510 RIO DE BAYAMON AT FLOOD CHANNEL AT BAYAMON, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) NOV s 1982 04“. 8.9 .530 JAN r 1983 13... 27 .670 1 100 1 9 4 .7 <1 <1 MAR 18... 1.10 MAY 17... 8.0 .400 JUN 06... AUG 18... 7.5 .260 2 200 1 2 3 <.1 <1 <1 CHLOR- DI- PCB, ALDRIN, DANE, ODD, DDEr DDT, AZINON, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN , 1983 06... 1315 <.10 <.01 (.10 <.01 <.01 <.01 <.01 HEPTA- METH- DI- ENDO- HEPT A- CHLOR MALA- OXY- ELDRIN SULFAN, ENDRIN, ETHION, CHLOR, EPDXIDE LINDANE THION, CHLOR, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1983 06... <.01 <.01 <.01 <.01 <.01 <.01 .03 <.01 <.01 NAPH- THA- METHYL METHYL LINES, PARA- TRI- PARA- POLY- PER- TOX- TOTAL THION, THION, MIREX, THION, CHLOR. THANE APHENE, TRI- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL THION DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1983 06... <.01 <.01 <.01 <.01 <.10 <.10 <1 <.01 94 RIO PUERTO NUEVO BASIN 50048800 RIO PIEDRAS NEAR RIO PIEDRAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°22'15", long 66°03'40", at bridge on Winston Churchill Avenue in the El Seri of Highway 176, and 2.5 mi (4.0 km) southwest of Rio Piedras plaza. 95 rial Housing area, 0.5 mi (0.8 km) west 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 1982 TO SEPTEMBER 1983 OXYGEN. OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM.. FECAL, FECAL, FLOW. CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR". LEVEL) (COLS./ PER DATE (CFS) (UMMOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 01... 1055 JAN 1983 17... 1110 MAR 15... 1010 MAY 16... 1220 JUN 06... 1540 AUG 15... 0855 6.2 345 7.4 25.5 9.0 5.5 386 7.3 22.0 3.0 8.0 4.2 540 7.4 25.0 4.9 5.2 12 293 7.8 26.0 4.7 7.6 5.0 377 7.8 29.0 8.6 6.5 294 7.6 24.5 43 7.2 10 36000 34000 30 K73000 47000 36 K67000 17000 50 3600 23000 112 84 24 K10000 52000 11 9 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO FLUO- HARD- NESS, CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE. NESS NONCAR- On- On- DIS- SORP- On- FIELD DIS- DIS- DIS- (MG/L 8ONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MS/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV r 1982 01... 120 JAN e 1983 17... 140 0 35 12 27 1.0 2.6 140 MAR 15... 140 MAY 16... 130 9 32 12 27 1.1 2.6 120 JUN 06... 140 AUG 15... 110 0 28 9.4 19 .8 2.4 118 15 28 .20 24 27 .10 15 22 <.10 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV ' 1982 01... 8 .93 .070 1.0 .160 .44 .60 1.6 JAN , 1983 17... 37 241 3.6 18 1.3 .130 1.4 .720 .38 1.10 2.5 MAR 15... <1 .90 .200 1.1 .940 1.4 2.30 3.4 MAY 16... 33 230 7.7 4 .78 .020 .80 .230 .17 .40 1.2 JUN 16... 95 29 196 3.4 30 .77 .130 .90 .050 .85 .90 1.8 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELF- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SI) AS AG) NOV r 1982 01... 7.1 .220 JAN , 1983 17... 11 .300 2 100 1 <1 5 1.0 <1 <1 MAR 15... 15 .410 MAY 16... 5.3 .170 JUN 06... AUG 15... 8.0 .180 2 200 2 <1 4 <.1 <1 K = non-ideal count RIO PUERTO NUEVO BASIN 50048800 RIO PIEDRAS NEAR RIO PIEDRAS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHLOR- DI- PCB, ALDRIN, DANE, 000, DDE, DDT, AZINON, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN , 1983 06... 1540 <.10 <.01 <.10 <.01 <.31 <.01 (.01 HEPTA- METH- DI- ENDO- HEPTA- CHLOR MALA- OXY- ELDRIN SULFAN, ENDRIN, ETHION, CHLORr EPDXIDE LINOANE THION, CHLOR, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN , 1983 06... <.01 <.01 <.01 <.01 (.01 <.01 (.01 <.01 <.01 NAPH- THA- METHYL METHYL LENES, PARA- TRI- PARA- POLY- PER- TOX- TOTAL THION, THION, MIREX, THION, CHLOR. THANE APHENE, TRI- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL THION DATE (UG/L) (UG/L) (UG/L) (US/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN , 1983 06... <.01 (.01 <.01 <.01 <.10 <.10 <1 <.01 96 RIO PUERTO NUEVO BASIN 50049100 RIO PIEDRAS AT HATO REY, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°24'34", long 66°04'10", at bridge on Avenida Pifiero 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 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLT- STREP... SPE- On- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PM TUR... OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- On- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 01... 1445 11 385 7.6 30.0 8.3 110 19 100000 5100 JAN , 1983 17... 1345 13 430 7.8 25.0 3.9 10.8 131 30 33000 3200 MAR 15... 1300 11 422 7.6 27.5 2.0 4.4 56 46 210000 53000 MAY 16... 1510 23 340 7.6 29.0 7.0 6.6 86 58 K77000 K19000 AUG 15... 1140 17 326 7.4 29.0 3.1 40 35 340000 81000 97 HARD- HARD- NESS, CALCIUM NESS NONCAR- DIS- (MG/L BONATE SOLVED AS (MG/L (MG/L DATE CAC03) CAC03) AS CA) MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- SIUM, SODIUM, AO- S/UM, LINITY SULFATE RIDE, RIDE, DIS- DIS- SORP.". DIS- FIELD DIS- DIS- DIS- SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1982 01... JAN , 1983 17... 160 MAR 15... MAY 16... 160 AUG 15... 110 140 0 44 12 29 1.0 3.3 160 17 32 .20 160 7 43 12 29 1.0 3.5 150 25 28 .20 0 32 8.2 23 1.0 3.1 115 17 25 .20 SOLIDS, SOLIDS, NITRO SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONZA + NITRO- SOLVED TUENTS, SOLVED DEG. Co NITRATE NITRITE NO244403 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 01... JAN 1983 17... 32 265 9.0 MAR 15... MAY 16... 28 259 16.1 AUG 15... 25 202 9.3 7 1.3 .150 1.4 .330 .47 .80 2.2 2 1.3 .120 1.4 .530 .37 .90 2.3 178 .96 .140 1.1 1.50 1.1 2.60 3.7 10 .72 .080 .80 .540 .00 .50 1.3 25 .78 .220 1.0 .360 2.5 2.90 3.9 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV 1982 01... 9.7 .430 JAN , 1983 17... 10 .380 2 100 1 <1 8 .3 <1 <1 MAR 15... 16 .730 MAY 16... 5.8 .250 AUG 15... 17 2 100 2 1 19 .4 <1 <1 K = non-ideal count 98 RIO PUERTO NUEVO BASIN 50049820 LAGUNA SAN JOSE NO. 2 AT SAN JUAN, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°25'46", long 66°02'10", 0.2 mi (0.3 km) east of Cairn de Martin Pefia, 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 1982 TO SEPTEMBER 1983 OXYGEN, SPE- DIS- CIFIC SOLVED SAM- CON- PH OXYGEN, (PER- PLING DUCT- (STAND- TEMPER- DIS- CENT TIME ANCE ARD ATURE CENT DEPTH SOLVED SATUR- DATE (FEET) (UMHOS) UNITS) (DEG C) (MG/I) ATION) COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) NOV , 1982 24... 0945 1.00 26100 8.5 27.0 6.0 82 FEB , 1983 08... 0955 1.00 23600 8.2 25.5 1.8 24 MAR 25... 1240 1.00 30500 3.5 29.0 8.0 115 MAY 24... 1010 1.00 11900 3.5 28.5 4.9 66 AUG 25... 1010 1.00 13800 8.8 28.5 9.0 123 K1100 K10 K96000 8300 K8200 K550 52000 6000 K10000 K1000 SOLIDS, NITRO- ALKA- RESIDUE NITRO- NITRO- NITRO- NITRO- GEN,AM- LINITY AT 105 GEN, GEN, GEN, GEN, MONIA + PHOS- FIELG DEG. C. NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC PHORUS. (MG/L SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE CAC03) (MG/L) AS N) AS N) AS N) AS N) AS N) AS P) CARBON. ORGANIC TOTAL (MG/L AS C) NOV . 1982 24... 140 4 .020 <.10 .160 1.3 1.50 .540 8.3 FEB , 1983 08... 150 34 .020 (.10 .660 1.9 2.60 .710 9.2 MAR 25... 160 77 .020 (.10 .390 2.4 2.80 .840 11 MAY 24... 120 42 .020 (.10 .080 2.5 2.60 .690 14 AUG 25... 95 K = non-ideal 88 count .010 <.10 .080 1.8 1.90 .450 13 RIO PUERTO NUEVO BASIN 50049920 BAHIA DE SAN JUAN NO. 5 AT SAN JUAN, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°26 37", long 66°05'11", 0.4 mi (0.6 km) west of Puente de la Constituci6n, and 0.5 mi (0.8 km) south from U.S. Naval Reservation. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN. COLI- STREP- SOLIDS. SPE- DIS- FORM, TOCOCCI ALKA- RESIDUE CIFIC SOLVED FECAL, FECAL, LINITY AT 105 SAM- CON- PH OXYGEN. (PER- 0.7 KF AGAR FIELD DEG. Co PLING DUCT- (STAND- TEMPER- DIS- CENT UM-MF (COLS. (MG/L SUS'''' TIME DEPTH ANCE ARD ATURE SOLVED SATUR- (COLS./ PER AS PENDED DATE (FEET) (UMHOS) UNITS) (DEG C) (MG/L) ATION) 100 ML) 100 ML) CAC03) (MG/L) NOV , 1982 24... 1140 1.00 43700 7.5 28.0 2.8 42 K8800 2600 140 6 FEB . 1983 08... 1125 1.00 38500 7.6 25.5 1.6 22 230000 4500 140 32 MAR 25... 1100 1.00 41300 7.3 27.0 1.0 15 430000 K11000 150 66 MAY 24... 1210 1.00 12200 7.9 27.0 4.8 63 K95000 3000 110 78 AUG 25... 1145 1.00 32200 7.8 29.5 5.4 79 280000 4700 129 56 NITRO- NITRO- NITRO- NITRO- NITRO- NITRO."' GEN,AM- GEN, GEN. GEN. GEN, GEN, MONIA + NITRO- NITRO- PHOS- CARBON• NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEM, PHORUS, ORGANIC TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) AS P) AS C) NOV . 1982 24... .51 .090 .60 1.00 .60 1.60 2.2 9.7 .310 5.5 FEB . 1983 08... .13 .070 .20 1.70 .70 2.40 2.6 12 .560 7.0 MAR 25... .06 .040 .10 1.90 .50 2.40 2.5 11 .680 9.7 MAY 24... .020 (.10 .46 1.0 1.50 .490 5.9 AUG 25... .07 .030 .10 .95 .55 1.50 1.6 7.1 .310 4.9 99 101 SAN JUAN OCEANO ATLANTICO LOIZA ALDEA Coastal basin L Coostal basin RIO GRANDE 0620 E • CANOVANA 0600 A J40602 0591 TRUJI LO ALTO 0 0619 j ; tor, " ° 0592 ats ) AGUAS BUENAS .5 4 0 55310 U GURABO 0566 • 0550 CA AS JUNCOS 0545 556 0564 0557 de /de p4, bra SN A .51 LAS LORENZO lb Anton Ruiz PIEDRAS . basin 051140 tj-Drainage boundary 051310 Rib de la Plato basin Rio Humacao basin EXPLANATION A0509 SURFACE—WATER STATION AND NUMBER Rib Grande de Patillas basin r) 1 0619 LOW—FLOW STATION AND NUMBER Map area Rio Guayana, basin v0564 S)-V,INTI-1,16WATHER SAN JUAN • 52 WELL AND WELL NUMBER O I 2 3 6 'KILOMETERS 1 I 1 1 1 O 1 MILES Figure 18.--Rio Grande de Loiza basin. 102 RIO GRANDE DE LOIZA BASIN 50050300 QUEBRADA BLASINA NEAR CAROLINA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°23'27", long 65°58'28", at bridge on Highway 3, 1.4 mi (2.3 km) south of Valle Arriba Heights housing area, and 1.2 mi (1.9 km) west-southwest of Carolina plaza. DRAINAGE AREA.--2.96 sq mi (7.67 sq km). PERIOD OF RECORD.--Water years 1973 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, CXYGEN COLI- SPE- DIS- DEMAND, FORM, STREAM- CIFIC SOLVED CHEM- FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 INSTAN- DUCT- (STAND- TEMPER- 3ID- DIS- CENT (HIGH UM-MF TIME TANEOUS ANCE ARD ATURE ITV SOLVED SATUR- LEVEL) (COLS./ DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) NOV 1982 08... 1010 4.1 590 7.1 28.0 4.9 .0 0 63 2400000 JAN , 1983 14... 1400 4.9 557 6.8 27.0 4.8 .0 0 -- K8400000 MAR 09... 1025 4.2 634 7.4 26.0 3.1 .0 0 76 >1000000 MAY 10... 1430 6.4 478 7.2 30.0 4.5 .0 0 74 K1.0E+07 AUG 15... 1440 5.4 563 6.9 31.0 .0 0 220 5800000 STREP- TOCOCCI HARD- MAGNE- SODIUM POTAS- ALKA- FECAL, HARD- NESS, CALCIUM SLUM, SODIUM, AD- SIUM, LINITY SULFATE KF AGAR NESS NONCAR- DIS- DIS.". DIS- SORP- DIS- FIELD DIS- (COLS. (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED PER AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L DATE 100 ML) CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) NOV , 1982 08... K110000 190 JAN f 1983 14... K550000 150 0 47 8.4 43 1.6 7.1 170 21 MAR 09... >1000000 200 MAY 10... 6100000 160 0 51 8.6 47 1.7 6.5 200 23 AUG 15... K982000 170 10 55 8.8 40 1.4 6.0 164 14 SOLIDS, SOLIDS, CHLO- FLUO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- RIDE, RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, DIS- DIS- SOLVED TUENTS, SOLVED DEG. C, NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L DATE AS CL) AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) NOV , 1982 08... 14 .020 (.10 12.0 .00 JAN , 1983 14... 54 .20 26 309 4.1 30 .030 <.10 13.0 47 MAR 09... 6 .010 <.10 11.0 5.0 MAY 10... 52 .20 26 334 5.8 <1 .020 <.10 6.30 3.0 AUG 15... 48 .20 25 295 4.3 13 .060 <.10 .040 13 NITRO- CHRO- GEN,AM- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, MONIA + PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL ORGANIC PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS N) AS P) AS AS) AS 8A) AS CD) AS CR) AS P8) AS HG) AS SE) AS AG) NOV r 1982 08... 12.0 2.50 JAN , 1983 14... 60.0 2.80 3 100 1 10 4 .2 <1 <1 MAR 09... 16.0 2.90 MAY 10... 9.30 3.10 AUG 15... 13.0 3 200 4 <1 8 1.0 <1 <1 K = non-ideal count; (1.0E+07 = 10000000) 103 RIO GRANDE DE LOIZA BASIN 50050900 RIO GRANDE DE LOIZA AT QUEBRADA ARENAS, PR LOCATION.--Lat 18°07'10", long 65°59'22", Hydrologic Unit 21010005, at intersection of Highways 181 and 9990, 0.2 mi (0.3 km) above con­ fluence with Rio Emajagua and about 7.1 mi (11.4 km) southwest of San Lorenzo. DRAINAGE AREA.--6.00 sq mi (15.54 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1977 to current year. GAGE.--Water-stage recorder. Altitude of gage is 175 ft (53.3 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--6 years (1978-83), 31.4 cu ft/s (0.889 cu m/s), 71.07 in/yr (1,810 mm/yr), 22,750 acre-ft/yr (28.1 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 8,950 cu ft/s (253 cu m/s) July 18, 1979, gage height 13.4 ft (4.08 m) from floodmark, from rating curve extended above 500 cu ft/s (14.2 cu m/s) on basis of step-backwater analysis; minimum, 2.8 cu ft/s (0.079 cu m/s) May 5,6, 1979. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 2,000 cu ft/s (56.6 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) June 16 0245 *2,660 75.3 8.92 2.719 June 18 0500 2,000 56.6 8.20 2.499 Minimum discharge, 4.9 cu ft/s (0.139 cu m/s) Apr. 8-13. DISCHARGE, IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 25 38 94 20 10 6.9 5.9 7.6 13 25 134 23 2 19 24 46 18 10 6.4 5.9 8.1 12 46 63 41 3 17 22 33 16 9.8 6.6 5.6 8.8 10 41 32 28 4 16 23 40 21 11 6.4 5.4 7.4 11 291 27 24 5 15 53 30 44 11 5.9 5.4 8.0 11 174 33 21 6 15 40 26 29 10 5.3 5.9 16 20 91 24 19 7 14 33 24 22 10 6.2 5.4 10 12 88 21 18 3 14 39 22 22 9.8 12 5.1 7.7 12 48 20 18 9 14 29 21 84 9.2 17 4.9 7.0 26 38 19 17 10 13 34 20 31 8.9 6.6 4.9 6.6 13 33 20 16 11 12 42 20 23 8.5 6.4 4.9 5.8 11 30 25 17 12 11 66 19 29 8.2 64 4.9 6.0 11 27 31 18 13 34 42 17 20 8.7 22 5.4 6.4 21 26 32 16 14 14 26 17 17 9.9 12 6.2 11 92 25 33 15 15 12 23 26 16 8.5 11 5.9 10 95 23 31 18 16 13 24 18 17 7.8 9.2 5.6 8.7 296 25 72 25 17 56 23 16 16 8.5 8.1 13 13 60 26 188 18 18 30 52 15 14 7.7 7.8 30 14 192 34 78 16 19 53 61 14 13 7.2 7.6 12 97 39 29 43 14 20 67 136 22 12 7.2 7.4 18 27 34 30 38 16 21 55 39 16 12 8.5 7.2 115 13 27 23 178 102 22 31 28 22 11 7.2 7.2 16 10 23 21 43 39 23 167 30 15 11 6.8 7.0 9.8 23 22 81 28 38 24 32 25 16 11 6.9 7.1 8.1 172 20 52 25 48 25 28 24 14 15 6.9 6.7 7.1 44 19 22 59 65 26 25 22 14 19 6.9 5.9 6.6 24 18 19 54 128 27 21 22 13 13 7.5 5.8 8.8 18 31 18 36 38 28 27 28 13 12 7.5 5.8 16 16 20 62 92 37 29 20 27 12 11 --- 5.4 9.3 14 17 125 33 25 30 39 99 21 12 5.6 7.0 18 44 36 29 58 31 46 --- 78 11 5.9 --- 14 --- 36 25 --- TOTAL 955 1174 774 621 240.1 304.4 364.0 652.1 1232 1645 1566 976 MEAN 30.8 39.1 25.0 20.0 8.58 9.82 12.1 21.0 41.1 53.1 50.5 32.5 MAX 167 136 94 84 11 64 115 172 296 291 188 128 MIN 11 22 12 11 6.8 5.3 4.9 5.8 10 18 19 14 CFSM 5.13 6.52 4.17 3.33 1.43 1.64 2.02 3.50 6.85 8.85 8.42 5.42 IN. 5.92 7.28 4.30 3.35 1.49 1.89 2.26 4.04 7.64 10.20 9.71 6.05 AC-FT 1890 2330 1540 1230 476 604 722 1290 2440 3260 3110 1940 CAL YR 1982 TOTAL 10241.8 MEAN 28.1 MAX 304 MIN 5.6 CFSM 4.63 IN 63.49 AC-FT 20310 WTR YR 1983 TOTAL 10503.6 MEAN 28.8 MAX 296 MIN 4.9 CFSM 4.80 IN 65.11 AC-FT 20830 WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 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) OCT, 12 1345 11 132 29.0 MAY. 12 0915 6.4 157 26.0 NOV. 03 1350 20 140 26.5 JUN. 22 1330 23 129 29.0 DEC. 15 1200 17 -- 23.5 JUL, 13 1245 26 178 27.0 JAN. 18 1000 15 163 22.5 JUL, 27 0920 20 142 26.0 FEB, 10 1200 9.2 180 23.5 AUG. 02 1110 52 113 26.0 MAR, 01 1212 6.9 152 27.0 SEP. 08 1355 18 133 29.5 APR, 19 1200 3.8 165 28.0 -- 104 RIO GRANDE DE LOIZA BASIN 50051310 RIO CAYAGUAS AT CERRO GORDO, PR LOCATION.--Lat 18°09'27", long 65°57'29", Hydrologic Unit 21010005, on top of pumphouse at dam off Highway 912, at Barrio Cerro Gordo, 2.0 mi (3.2 km) south of San Lorenzo. DRAINAGE AREA.--10.2 sq mi (26.4 sq km). WATER DISCHARGE RECORDS PERIOD OF RECORD.--October 1977 to current year. GAGE.--Water-stage recorder and concrete control. Altitude of gage is 150 ft (46 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--6 years (1978-83), 49.4 cu ft/s (1.399 cu m/s), 65.77 in/yr (1,671 mm/yr), 35,790 acre-ft/yr (44.1 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 13,200 cu ft/s (374 cu m/s), Aug. 31, 1979, gage height 9.44 ft (2.877 m), from rating curve extended above, 1,000 cu ft/s (28.3 cu m/s) on the basis of slope-area measurement; minimum discharge, 7.1 cu ft/s (0.201 cu m/s), Feb. 4, May 3, 1981, Apr. 12, 13, 16, 17, 1983. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 2,500 cu ft/s (70.8 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) June 18 0615 *5,920 168 7.27 2.216 Aug. 21 1230 3,250 92 6.01 1.832 Minimum discharge, 7.1 cu ft/s (0.201 cu m/s) Apr. 12, 13, 16, 17. DISCHARGE. IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 31 55 187 34 21 15 12 17 18 27 110 43 2 29 43 55 32 21 14 11 13 17 38 109 71 3 27 37 44 29 20 13 11 17 16 38 40 48 4 26 37 45 31 21 13 12 15 18 145 36 43 5 26 70 44 41 20 13 11 18 16 806 36 40 6 25 55 38 40 19 13 9.9 17 17 172 35 38 7 24 40 36 32 19 14 9.5 18 14 90 31 37 8 24 49 35 31 19 20 9.2 14 15 58 30 36 9 23 38 34 53 18 21 .8.3 13 24 47 28 35 10 23 43 33 42 18 15 8.3 13 17 41 29 34 11 22 54 32 34 18 15 8.5 12 14 38 27 35 12 23 43 32 42 18 119 8.2 11 16 37 25 33 13 29 51 31 31 18 42 8.5 13 14 35 25 31 14 28 37 32 29 19 26 10 17 24 34 30 30 15 24 34 37 23 19 23 11 19 27 32 25 32 16 24 44 33 23 17 22 8.3 18 134 34 35 38 17 51 38 31 26 17 22 9.7 17 51 47 218 33 18 47 46 31 26 17 21 39 16 702 58 70 31 19 86 88 29 25 17 20 19 21 47 41 39 30 20 178 105 39 25 17 19 23 25 36 35 34 30 21 51 65 31 24 18 17 87 15 34 33 476 47 22 49 42 31 23 17 16 29 14 29 31 78 44 23 209 43 29 23 16 15 21 22 27 36 51 43 24 50 37 30 23 17 16 19 168 26 83 47 86 25 44 37 27 30 17 16 17 62 24 32 88 44 26 40 35 28 32 17 15 16 34 21 29 104 92 27 37 33 28 24 16 14 17 27 34 28 57 39 28 38 38 28 23 16 14 33 25 25 32 91 35 29 33 40 27 22 --- 13 26 22 21 123 53 30 30 42 101 28 22 12 17 20 24 48 51 32 31 48 --- 73 21 12 --- 20 --- 46 45 --- TOTAL 1411 1483 1238 926 507 640 529.4 758 1552 2374 2153 1240 MEAN 45.5 49.4 39.9 29.9 18.1 20.6 17.6 24.5 51.7 76.6 69.5 41.3 MAX 209 105 187 53 21 119 87 168 702 806 476 92 MIN 22 33 27 21 16 12 8.2 11 14 27 25 30 CFSM 4.46 4.84 3.91 2.93 1.78 2.02 1.73 2.40 5.07 7.51 6.81 4.05 IN. 5.15 5.41 4.51 3.38 1.85 2.33 1.93 2.76 5.66 8.66 7.85 4.52 AC-FT 2800 2940 2460 1340 1010 1270 1050 1500 3080 4710 4270 2460 CAL YR 1982 TOTAL 14811.1 MEAN 40.6 MAX 741 MIN 7.8 CFSM 3.98 IN 54.01 AC-FT 29380 WTR YR 1983 TOTAL 14811.4 MEAN 40.6 MAX 306 MIN 8.2 CFSM 3.98 IN 54.01 AC-FT 29380 WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW. SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TORE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) OCT. 12 1030 24 121 25.5 MAY. 11 1330 12 136 30.0 NOV, 03 1040 36 128 24.0 JUN. 28 1216 26 28.5 DEC. 15 1000 31 112 22.0 JUL, 14 1240 34 133 27.5 JAN. 17 1320 27 156 23.0 JUL, 26 1350 29 126 30.0 FEB, 1C 0940 19 173 21.0 AUG, 18 1025 63 90 25.0 MAR. 01 0929 16 136 23.5 SEP. 07 1400 38 122 28.0 APR. 21 1615 97 175 28.0 105 RIO GRANDE DE LOIZA BASIN 50055000 RIO GRANDE DE LOIZA AT CAGUAS, PR LOCATION .--Lat 18°14'33", long 66°00'34", Hydrologic Unit 21010005, on right bank 250 ft (76 m) upstream from bridge on Highway 189, 1.2 mi (1.9 km) downstream from Rio Turabo, and 1.8 mi (2.9 km) east of Plaza de Caguas. DRAINAGE AREA.--89.8 sq mi (232.6 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--1959 (low-flow measurement only), February to November 1959 (monthly measurements only), December 1959 to current year. GAGE.--Water-stage recorder.--Datum of gage is 143.28 ft (43.672 m) above mean sea level (datum of 1941). REMARKS.--Records fair. AVERAGE DISCHARGES.--23 years (1961-83), 219 cu ft/s (6.202 cu m/s), 33.12 in/yr (841 mm/yr), 158,700 acre-ft/yr (196 cu hm/yr); median of yearly mean discharges, 210 cu ft/s (5.95 cu m/s), 152,000 acre-ft/yr (187 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 71,500 cu ft/s (2,025 cu m/s) Sep. 6, 1960, gage height, 31.17 ft (9.501 m), from rating curve extended above 6,000 cu ft/s (170 cu m/s) on basis of slope-area measurement; minimum daily discharge, 10 cu ft/s (0.283 cu m/s) Apr. 5, 10, 29, 1968. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 8,000 cu ft/s (227 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Mar. 12 1700 9,090 257 14.42 4.395 July 5 1400 *11,800 334 15.63 4.764 July 4 2130 9,090 257 14.42 4.395 Aug. 21 1330 10,200 289 14.95 4.557 Minimum discharge, 34 cu ft/s (0.963 cu m/s) Apr. 13. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1?82 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 235 491 873 223 84 59 46 69 80 118 194 208 2 160 236 381 162 86 53 45 75 73 281 550 420 3 142 185 281 140 33 53 44 77 71 178 199 260 4 131 169 239 152 81 51 44 75 72 1060 163 210 5 126 241 258 188 85 51 40 81 70 3940 167 180 6 120 255 190 216 75 50 45 71 117 1200 163 150 7 115 198 174 177 75 63 41 95 105 847 131 140 8 111 196 161 152 74 74 40 67 68 474 120 140 9 106 163 153 401 71 123 40 56 131 296 113 130 10 102 185 143 268 70 71 38 52 96 229 113 120 11 100 386 137 182 70 57 41 48 68 192 107 130 12 98 646 132 244 65 2060 40 47 73 171 134 140 13 562 779 128 166 70 532 36 67 66 157 175 124 14 235 235 124 142 72 161 49 193 203 146 131 115 15 125 183 331 132 74 113 52 136 171 132 121 129 16 114 186 202 130 66 94 35 92 1830 141 213 141 17 232 175 141 124 67 81 41 80 445 200 1710 130 18 296 190 127 122 68 74 300 609 1780 358 550 121 19 448 512 114 115 63 68 84 507 334 191 227 116 20 1020 758 293 115 65 66 115 460 228 155 162 106 21 408 467 158 114 128 64 979 415 170 141 2680 454 22 390 230 135 111 79 61 193 180 137 127 671 264 23 1100 219 123 106 67 57 101 181 125 118 393 208 24 366 183 122 102 65 60 82 717 110 431 279 286 25 266 188 119 101 65 64 66 498 104 150 612 282 26 212 201 294 162 64 55 56 231 93 131 509 565 27 190 304 240 110 63 51 147 153 130 119 344 247 28 183 330 162 98 64 52 175 125 133 140 657 195 29 173 266 132 94 --- 52 130 109 91 785 358 149 30 207 1510 115 96 46 78 97 121 351 264 206 31 301 --- 817 92 46 --- 90 --- 225 230 --- TOTAL 8374 10267 6989 4737 2059 4562 3223 5753 7295 13184 12440 6066 MEAN 270 342 225 153 73.5 147 107 186 243 425 401 202 MAX 1100 1510 873 401 128 2060 979 717 1830 3940 2680 565 MIN 98 163 114 92 63 46 35 47 66 118 107 106 CFSM 3.01 3.81 2.51 1.70 .82 1.64 1.19 2.07 2.71 4.73 4.47 2.25 IN. 3.47 4.25 2.90 1.96 .85 1.89 1.34 2.38 3.02 5.46 5.15 2.51 AC-FT 16610 20360 13860 9400 4080 9050 6390 11410 14470 26150 24670 12030 CAL YR 1982 TOTAL 82677 MEAN 227 MAX 3600 MIN 37 CFSM 2.53 IN 34.25 AC-FT 164000 WTR YR 1983 TOTAL 84949 MEAN 233 MAX 3940 MIN 35 CFSM 2.60 IN 35.19 AC-FT 168500 106 RIO GRANDE DE LOIZA BASIN 50055000 RIO GRANDE DE LOIZA AT CAGUAS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1959 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP SPE'.. DIS- DEMAND, FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL. FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DIG C) (NTU) (MG/L) ATION) CMG/L) 100 ML) 100 ML) 1982 1320 164 192 7.3 27.5 20 8.0 102 18 K8500 270 1983 1300 116 220 7.1 25.0 22 8.4 102 30 3800 600 1125 71 231 7.5 26.5 320 6.8 85 54 K67000 15000 1045 78 223 7.6 27.5 35 7.1 91 10 580 6700 1215 109 212 7.4 29.0 20 7.6 99 180 K6800 310 HARD- NESS (MG/L AS DATE CAC03) HARD- NESS. NONCAR- BONATE (MG/L CAC03) CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM. DIS- SOLVED (MG/L AS NA) SODIUM AD- SORP- TION RATIO POTAS- ALKA- CHLO- FLUO- SIUM, LINITY SULFATE RIDE. RIDE. DIS- FIELD DIS- DIS- DIS- SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L AS (MG/L (MG/L (MG/L AS K) CAC03) AS SO4) AS CL) AS F) NOV r 1982 9... JAN r 1983 19... 70 MAR 10... MAY 04... 72 AUG 11... 65 59 0 17 6.8 21 1.1 1.9 72 13 16 .10 71 o 13 6.6 20 1.1 2.1 75 17 20 .20 o 16 6.0 20 1.1 1.5 70 12 17 .20 SOLIDS, SOLIDS. NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + SOLVED TUENTS, SOLVED DEG. C. NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE 5102) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) NITRO- GEN. TOTAL (MG/L AS N) NOV r 1982 9... 28 .48 .020 .50 .050 .55 .60 1.1 JAN r 1983 19... 33 152 47.6 6 .54 .060 .60 .220 .38 .60 1.2 MAR 10... 586 .67 .230 .90 .860 .34 1.20 2.1 MAY 04... 34 163 34.3 22 .60 .100 .70 .240 .36 .60 1.3 AUG 11... 34 149 43.8 16 .45 .050 .50 .200 .30 .50 1.0 NOV , 9... JAN • 19... MAR 10... MAY 04... AUG 11... BARIUM, CADMIUM NITRO- PHOS- TOTAL TOTAL GEN, PHORUS. ARSENIC RECOV- RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CO) NOV 1982 9... 4.9 .110 JAN r 1983 19... 5.3 .220 2 100 1 MAR 10... 9.3 .620 MAY 04... 5.8 .290 AUG 11... 4.4 .190 2 100 1 STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) OCT, 08 1320 113 197 29.0 DEC. 23 0950 123 247 23.5 FEB, 09 0950 67 280 24.0 APR, 06 1030 44 326 28.0 K = non-ideal count CHRO- MIUM, TOTAL LEAD, TOTAL MERCURY TOTAL SELE- SILVER. TOTAL RECOV- ERABLE RECOV- ERABLE RECOV- ERABLE NIUM, TOTAL RECOV- ERABLE (UG/L (UG/L (UG/L (UG/L (UG/L AS CR) AS P8) AS HG) AS SE) AS AG) 5 11 .2 1 <1 6 <.1 <1 <1 DATE TIME STREAMFLOW, INSTANTANEOUS SPECIFIC CON- DUCTANCE TEMPERA- TURE (CFS) (UMHOS) (DEG C) JUN. 22 1055 140 .... 29.0 JUL, 28 1015 121 209 29.5 SEP. 12 1655 139 217 30.0 107 RIO GRANDE DE LOIZA BASIN 50055250 RIO CAGUITAS AT HIGHWAY 30 AT CAGUAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°15'11", long 66°01'26", at Highway 30 bridge, and 0.8 mi (1.3 km) east of Caguas plaza. DRAINAGE AREA.--14.1 sq mi (36.5 sq km). PERIOD OF RECORD.--Water years 1972 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 83 OXYGEN, OXYGEN COLI- STREP- SPE- 015- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- MS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 23... 1350 16 463 6.8 26.0 7.5 .6 7 25 K610000 68000 JAN r 1983 18... 1510 12 528 7.1 27.0 5.0 5.0 63 69 39000 K13000 MAR 10... 1420 4.7 585 7.4 29.0 5.1 2.4 32 79 K6200000 215000 MAY 11... 1330 8.1 544 7.4 32.5 .90 2.0 28 38 560000 31000 AUG 16... 1240 14 385 7.4 29.0 3.6 47 63 43000 48000 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUD- HARD- NESS, CALCIUM MIMI, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- On- SORP- DIS- FIELD DIS- 015- DIS- (MG/L 8ONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1982 23... 130 JAN , 1983 18... 180 42 48 15 39 1.3 3.3 140 66 40 .40 MAR 10... 150 MAY 11... 200 27 54 15 50 1.6 4.9 170 87 48 .60 AUG 16... 130 31 37 10 27 1.1 3.5 103 42 28 .30 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 23... 20 1.3 .220 1.5 1.90 1.6 3.50 5.0 JAN r 1983 18... 34 330 10.6 <1 1.5 .150 1.6 1.10 1.1 2.20 3.8 MAR 10... 11 .98 .220 1.2 2.80 2.3 5.10 6.3 MAY 11... 36 397 8.7 5 .81 .290 1.1 2.70 2.8 5.50 6.6 AUG 16... 25 235 8.9 42 .94 .160 1.1 .150 1.8 1.90 3.0 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS P3) AS HG) AS SE) AS AG) NOV , 1982 23... 22 .820 JAN , 1983 18... 17 .790 2 <100 5 13 6 .2 <1 <1 MAR 10... 28 1.70 MAY 11... 29 1.90 AUG 16... 13 2 <100 2 2 22 .4 <1 <1 K = non-ideal count 108 RIO GRANDE DE LOIZA BASIN 50055400 RIO BAIROA NEAR CAGUAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°15'28", long 66°02'13", at bridge on Highway 1, about 2.5 mi (4.0 km) upstream from Rio Grande de Loiza, and 1.4 mi (2.3 km) north of Caguas plaza. DRAINAGE AREA.--5.4 sq mi (14.0 sq km). PERIOD OF RECORD.--Water years 1958, 1962-66, 1973-74, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW. CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) CMG/L) ATION) (MG/L) 100 ML) 100 ML) NOV r 1982 02... 1435 3.6 358 7.3 25.5 29 6.6 81 22 72000 21000 JAN , 1933 05... 1435 7.5 418 6.8 24.0 25 3.3 45 59 280000 210000 MAR 16... 1120 2.6 485 7.8 26.5 1.1 7.0 88 23 27000 K2100 MAY 04... 1435 2.3 413 7.7 27.5 42 6.2 79 18 4300 77000 AUG 17... 1010 24 259 7.4 26.5 140 6.4 80 40 K730000 660000 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM. SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- ()IS." (MG/L BONATE SOLVED SCLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MS/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1982 02... 110 JAN , 1983 05... 140 13 34 14 30 1.1 5.1 130 20 31 .20 MAR 16... 140 MAY 04... 160 11 38 16 31 1.1 4.9 150 22 51 .30 AUG 17... 78 0 20 6.9 16 .8 5.0 82 15 20 .20 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN.AM- DIS- CONSTI- On* AT 105 GEN, GEN, GEN, GEN, GEN, MONZA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/t (MG/L (MG/L DATE 5IO2) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1932 02... 14 1.4 .090 1.5 .150 .75 .90 2.4 JAN , 1983 05... 29 241 4.9 12 1.3 .120 1.4 2.80 2.4 5.20 6.6 MAR 16... <1 1.8 .030 1.8 .120 .18 .30 2.1 MAY 04... 32 285 1.8 42 1.3 .050 1.3 .260 .44 .70 2.0 AUG 17... 6.3 139 9.0 26 .89 .110 1.0 1.10 2.6 3.70 4.7 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV TOTAL TOTAL TOTAL ERA8LE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS 8A) AS CD) AS CR) AS P8) AS HG) AS SE) AS AG) NOV , 1982 02... 11 .610 JAN r 1983 05... 29 2.20 3 200 .6 <1 <1 MAR 16... 9.3 .540 MAY 04... 8.9 .770 AUG 17... 21 1.10 3 100 2 20 16 <.1 <1 K = non-ideal count --- RIO GRANDE DE LOIZA BASIN 50056400 RIO VALENCIANO NEAR JUNCOS, PR 109 LOCATION.--Lat 18°12'58", long 66°55'34", Hydrologic Unit 21010005, on left bank at Highway 919, 0.5 mi (0.8 km) upstream from Quebrada Don Victor, 1.7 mi (2.7 km) upstream from Rio Gurabo and 1.0 mi (1.6 km) south of Juncos. DRAINAGE AREA.--16.4 sq mi (42.5 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1971 to current year. GAGE.--Water-stage recorder. Altitude of gage is 320 ft (98 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--12 years (1972-83), 50.1 cu ft/s (1.419 cu m/s), 41.49 in/yr (1,054 mm/yr), 36,300 acre-ft/yr (44.8 cu hm/yr); median of yearly mean discharges, 51 cu ft/s (1.44 cu m/s), 36,900 acre-ft/yr (45 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 23,300 cu ft/s (660 cu m/s) Aug. 31, 1979, gage height, 20.17 ft (6.148 m), from rating curve extended above 100 cu ft/s (2.83 cu m/s) on basis of slope-area measurement and step-backwater analysis; minimum, 2.3 cu ft/s (0.065 cu m/s) July 10, 1977, gage height, 0.29 ft (0.088 m). EXTREMES OUTSIDE PERIOD OF RECORD.--Approximate discharges (no stages were recorded) of major floods are as follows: Sept. 6, 1960, 37,100 cu ft/s (1,050 cu m/s); Oct. 9, 1970, 18,200 cu ft/s (515 cu m/s). EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 3,400 cu ft/s (96.3 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Mar 12 1630 4,200 119 8.42 2.566 Aug. 17 0615 4,020 114 8.26 2.518 July 5 1700 *7,340 208 11.23 3.423 Aug. 21 1830 6,890 195 10.87 3.313 Minimum discharge, 6.0 cu ft/s (0.170 cu m/s) Mar. 31, Apr. 1, 2. DISCHARGE, IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 49 141 124 36 14 9.7 6.4 12 14 23 35 36 2 33 49 57 30 14 9.6 6.6 24 14 90 63 90 3 28 36 47 24 14 9.6 7.4 18 13 35 32 49 4 26 34 42 31 14 9.5 9.3 16 20 135 27 36 5 26 47 40 28 14 9.2 8.8 26 20 1340 26 32 6 25 83 35 38 13 9.3 10 19 27 252 33 29 7 24 41 33 32 13 9.6 8.3 18 24 129 23 27 8 23 42 29 29 13 13 7.7 14 16 70 21 26 9 22 41 28 43 13 32 7.3 13 57 51 21 24 10 21 33 27 31 12 12 7.1 12 25 42 21 23 11 21 76 27 24 12 12 7.2 18 17 33 19 27 12 20 74 26 25 12 764 7.3 10 43 35 18 40 13 27 70 25 22 12 89 7.2 11 19 32 19 25 14 25 39 24 21 13 29 31 17 24 30 23 23 15 21 36 34 20 12 21 14 23 54 28 19 29 16 20 74 28 19 12 16 9.1 17 256 31 83 27 17 35 49 24 19 12 15 9.6 28 67 56 702 25 18 57 69 22 19 12 14 70 17 220 54 104 26 19 188 229 22 18 11 12 15 29 51 31 40 24 20 166 64 83 17 11 10 24 25 34 29 32 22 21 98 56 32 13 13 9.4 440 16 29 26 1 860 34 22 122 45 28 17 11 9.1 43 13 23 25 30 23 110 62 27 17 11 3.9 22 47 21 30 59 23 24 42 46 27 17 11 9.5 17 167 20 59 44 47 25 40 42 27 17 11 11 14 60 20 27 159 65 26 33 35 43 26 11 8.1 13 41 20 24 131 67 27 31 34 42 17 10 7.6 14 25 65 22 157 33 28 66 40 33 17 10 7.6 17 22 37 21 100 26 29 34 38 32 16 7.3 14 21 20 197 67 23 30 53 598 28 16 7.0 17 18 24 52 64 26 31 100 --- 164 15 6.6 --- 16 --- 42 41 TOTAL 1586 2323 1260 725 341 1197.6 884.3 813 1294 3556 4213 1019 MEAN 51.2 77.4 40.6 23.4 12.2 38.6 29.5 26.2 43.1 115 136 34.0 MAX 188 598 164 48 14 764 440 167 256 1840 1860 90 MIN 20 33 22 15 10 6.6 6.4 10 13 21 18 22 CFSM 3.12 4.72 2.48 1.43 .74 2.35 1.80 1.60 2.63 7.01 8.29 2.07 IN. 3.60 5.27 2.86 1.64 .77 2.72 2.01 1.84 2.93 8.07 9.56 2.31 AC-FT 3150 4610 2500 1440 676 2380 1750 1610 2570 7050 8360 2020 CAL YR 1982 TOTAL 19192.1 MEAN 52.6 MAX 1470 MIN 6.7 CFSM 3.21 IN 43.53 AC-FT 38070 WTR YR 1983 TOTAL 19211.9 MEAN 52.6 MAX 1860 MIN 6.4 CFSM 3.21 IN 43.58 AC-FT 38110 WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA. WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 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) OCT. 04 1520 26 216 28.5 APR, 20 1000 34 293 28.0 NOV. 04 1345 32 234 25.0 MAY, 11 0653 11 282 27.0 DEC. 22 0925 28 223 22.0 JUL, 14 1025 31 237 27.0 JAN, 13 1335 23 286 24.0 JUL, 26 1230 26 237 28.5 FEB. 08 1230 14 319 23.5 AUG, 10 1045 21 223 26.5 FEB. 28 1541 11 290 28.0 SEP. 06 1420 29 238 29.5 110 RIO GRANDE DE LOIZA BASIN 50057000 RIO GURABO AT GURABO, PR LOCATION.--Lat 18°15'30", long 65°58'05", Hydrologic Unit 21010005, on left bank, at bridge on Highway 181, 0.3 mi (0.5 km) east of Gurabo, and 4.5 mi (7.6 km) upstream from Rio Grande de Loiza. DRAINAGE AREA.--60.2 sq mi (155.9 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--1958 (occasional low-flow measurements only), January to September 1959 (monthly measurements only), October 1959 to current year. GAGE.--Water-stage recorder. Datum of gage is 136.58 ft (41.630 m) above mean sea level. REMARKS.--Records fair. AVERAGE DISCHARGE.--24 years (1960-83), 132 cu ft/s (3.738 cu m/s), 29.78 in/yr (756 mm/yr), 95,630 acre-ft/yr (118 cu hm/yr); median of yearly mean discharges, 127cu ft/s (3.60 cu m/s), 92,000 acre-ft/yr (113 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 74,600 cu ft/s (2,133 cu m/s) Sept. 6, 1960, gage height, 27.7 ft (8.44 m), from floodmark, from rating curve extended above 8,000 cu ft/s (227 cu m/s) on basis of slope-area measurement at gage height 21.6 ft (6.58 m), contracted opening, culvert and flow over road measurement at gage height 23.76 ft (7.242 m), and estimate of peak flow based on slope-area measurements of Rio Gurabo and Rio Valenciano, 7.0 mi (11.3 km) upstream, adjusted for channel storage and flow from intervening area; minimum, 4.5 cu ft/s (0.127 cu m/s) Feb. 21, 25, 1968. EXTREMES OUTSIDE PERIOD OF RECORD.--Approximate elevation to gage datum of the Aug. 4, 1945 flood, as pointed out by local residents, 26.6 ft (8.11 m). EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 3,000 cu ft/s (85.0 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Nov. 30 0915 3,360 95.2 8.94 2.725 Aug. 17 0815 3,520 99.7 9.17 2.795 Mar. 12 2115 4,530 128 10.57 3.222 Aug. 21 1915 *32,300 915 22.32 6.803 Apr. 21 0745 4,880 138 11.02 3.359 Aug. 25 1730 3,500 99.1 9.14 2.786 July 5 2015 14,800 419 17.76 5.413 Aug. 27 2045 6,190 175 12.60 3.840 Minimum discharge, 15 cu ft/s (0.425 cu m/s) Apr 13. DISCHARGE, IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 85 184 187 128 32 21 19 33 47 56 35 218 2 79 115 104 90 31 21 19 41 44 143 160 492 3 67 94 95 74 30 20 19 40 42 96 76 228 4 62 107 85 72 30 20 19 36 59 349 64 111 5 60 94 79 74 29 19 19 40 64 4710 62 97 6 57 119 71 110 29 19 19 52 65 1540 80 89 7 56 95 67 63 28 20 18 57 149 325 54 84 8 56 81 64 58 28 23 18 43 60 192 49 81 9 54 82 61 53 28 42 17 35 434 131 45 77 10 51 73 60 51 28 30 16 31 119 105 43 72 11 51 87 58 50 27 24 16 29 60 92 41 72 12 50 209 59 50 26 1040 16 23 86 84 39 86 13 77 285 56 49 26 268 15 28 51 77 39 68 14 86 97 56 49 26 59 40 36 50 71 41 63 15 55 82 72 48 28 41 39 97 328 66 36 64 16 58 155 92 48 26 32 26 72 1030 66 114 66 17 63 107 62 47 25 29 26 89 208 73 1270 62 18 114 i45 58 46 25 27 142 59 739 122 346 61 19 200 435 54 45 25 26 43 75 155 75 92 60 20 306 132 290 44 25 25 67 187 77 70 64 56 21 125 119 84 42 26 23 1270 80 90 66 8290 59 22 180 90 70 42 25 22 122 57 61 59 1170 73 23 247 184 62 40 24 22 72 317 53 57 248 72 24 128 96 61 40 22 21 48 410 46 138 186 77 25 100 89 82 39 22 23 38 178 45 68 774 104 26 95 79 233 38 23 22 35 119 42 55 410 128 27 86 97 275 37 22 20 269 114 73 50 1450 76 28 102 110 230 36 21 20 114 69 85 47 742 62 29 34 94 131 35 --- 20 56 67 49 336 306 59 30 94 920 84 34 20 44 53 55 155 450 81 31 123 --- 760 33 19 --- 52 --- 105 334 --- TOTAL 3051 4656 3852 1665 737 2038 2681 2639 4466 9579 17160 2998 MEAN 98.4 155 124 53.7 26.3 65.7 89.4 85.1 149 309 554 99.9 MAX 306 920 760 128 32 1040 1270 410 1030 4710 3290 492 MIN 50 73 54 33 21 19 15 28 42 47 36 56 CFSM 1.64 2.58 2.06 .89 .44 1.09 1.49 1.41 2.48 5.13 9.20 1.66 IN. 1.89 2.88 2.38 1.03 .46 1.26 1.66 1.63 2.76 5.92 10.60 1.85 AC-FT 6050 9240 7640 3300 1460 4040 5320 5230 8860 19000 34040 5950 CAL YR 1982 TOTAL 45253 MEAN 124 MAX 6830 MIN 14 CFSM 2.06 IN 27.96 AC-FT 89760 WTR YR 1983 TOTAL 55522 MEAN 152 MAX 8290 MIN 15 CFSM 2.53 IN 34.31 AC-FT 110100 -- RIO GRANDE DE LOIZA BASIN 50057000 RIO GURABO AT GURABO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1963 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) OCT, 04 1130 61 291 28.5 MAY, 05 0823 36 357 27.5 NOV' 04 1025 102 267 26.0 JUN. 22 1515 60 30.0 DEC, 23 1300 62 340 25.0 JUL, 26 1520 55 305 32.5 JAN, 17 1030 47 367 24.0 AUG, 11 0907 40 312 27.5 FEB, 09 1310 23 563 26.5 SEP. 07 1150 86 318 29.5 APR, 06 1430 19 439 28.0 111 112 RIO GRANDE DE LOIZA BASIN 50057025 RIO GURABO NEAR GURABO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°15'56", long 65°59'04", at bridge on Highway 941, 1.2 mi (1.9 km) west-northwest from gaging station 50057000, and 1.0 mi (1.6 km) northwest of Gurabo plaza. DRAINAGE AREA.--62.8 sq mi (162.7 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN. OXYGEN COLI- STREP- SPE- DIS- DEMAND. FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL. FECAL, FLOW. CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV . 1982 02... 1130 128 263 7.0 25.5 37 5.6 69 22 31000 5500 JAN , 1983 05... 1135 30 321 6.8 24.0 17 5.6 67 21 K10000 K1700 MAR 16... 1415 39 334 7.4 27.5 5.6 5.0 64 25 K1400 840 MAY 11... 1045 29 320 7.6 30.0 4.2 3.0 40 22 K76000 7500 AUG 16... 1040 42 357 7.4 29.0 11 4.2 55 24 K6000 7500 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS. CALCIUM SIUM. SODIUM. AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD CIS- DIS- DIS- (MG/L BON ATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CACO3) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1982 02... 78 JAN , 1983 05... 110 10 25 11 23 1.2 3.4 98 15 23 .10 MAR 16... 100 MAY 11... 110 0 25 12 24 1.2 4.9 120 25 31 .20 AUG 16... 110 0 25 12 29 1.2 3.3 115 19 29 .20 SOLIDS, SOLIDS. NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN. GEN, GEN, GEN, GEN. MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. C. NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDEO (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 02... 48 1.2 .200 1.4 .390 .71 1.10 2.5 JAN , 1953 05... 31 195 42.2 18 1.3 .130 1.4 .260 1.1 1.40 2.8 MAR 16... 12 1.4 .150 1.5 .540 .26 .80 2.3 MAY 11... 31 229 17.9 3 1.3 .160 1.5 .480 .82 1.30 2.8 AUG 16... 34 221 25.1 4 1.3 .190 1.5 .110 .69 .80 2.3 CHRO- BARIUM. CADMIUM MIUM, LEAD. MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN. PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NTUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS 8A) AS CD) AS CR) AS P8) AS HG) AS SE) AS AG) NOV 1982 02... 11 .420 JAN r 1983 05... 12 .530 2 200 2 <1 5 .3 <1 <1 MAR 16... 10 .520 MAY 11... 12 .920 AUG 16... 10 .450 2 100 1 <1 2 <.1 <1 <1 K = non-ideal count RIO GRANDE DE LOIZA BASIN 50059000 LAGO LOIZA AT DAMSITE, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°19'49", long 66°01'00", at pumphouse at damsite, and 1.9 mi (3.1 km) south of Trujillo Alto Plaza. DRAINAGE AREA.--208 sq mi (539 sq km). PERIOD OF RECORD.--Water years 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLT- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI ALKA- STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, LINITY FLOW, CON- PH OXYGEN, (PER- ICAL 0.7 KF AGAR FIELD INSTAN- DUCT- (STAND- TEMPER- DIS- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARD ATURE SOLVED SATUR- LEVEL) (COLS.! PER AS DATE (CFS) (UMHOS) UNITS) (DEG C) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CACO3) NOV , 1982 03... 1240 124 222 6.7 27.0 2.8 35 19 46 K41 62 JAN r 1983 14... 0850 124 718 6.4 24.0 1.2 14 K50 41 64 MAR 17... 1120 124 253 7.0 27.0 .8 10 <10 K1400 3500 80 MAY 13... 1135 124 232 6.8 28.0 .0 0 30 70 40 87 AUG 17... 1425 139 232 7.2 29.0 .0 0 27 96 120 72 SOLIDS, NITRO- RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA 4' NITRO- NITRO- PHOS- DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN. GEN, PHORUS, SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL PENOED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) AS P) NOV , 1982 03... 11 .31 .090 .40 .120 .38 .50 .90 4.0 .170 JAN , 1983 14... 28 .48 .020 .50 .110 .69 .80 1.3 5.8 .360 MAR 17... <1 .48 .220 .70 .330 .07 .40 1.1 4.9 .200 MAY 13... 10 <.010 <.10 .390 .21 .60 .470 AUG 17... 10 .020 <.10 .200 .80 1.00 .160 K = non-idoal count 113 114 RIO GRANDE DE LOIZA BASIN 50059100 RIO GRANDE DE LOIZA BELOW TRUJILLO ALTO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°21'35", long 66°00'15", 100 ft (30 m) downstream of Highway 181 bridge, 0.4 mi (0.6 km) northwest of Trujillo Alto plaza, and 2.2 mi (3.5 km) northeast of Lago Loiza Reservoir. DRAINAGE AREA.--213 sq mi (552 sq km). PERIOD OF RECORD.--Water years 1981 to current year. REMARKS: Flow controlled by Lago Loiza reservoir. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 DATE STREAM- FLOW, INSTAN- T/ME TANEOUS (CFS) SPE- CIFIC CON- PH DUCT- (STAND- ANCE ARD (UMHOS) UNITS) TEMPER- ATURE (DEG C) OXYGEN. OXYGEN COLI- STREP- DIS- DEMAND. FORM, TOCOCCI SOLVED CHEM- FECAL. FECAL. TUR- OXYGEN. (PER- ICAL 0.7 KF AGAR BID- DIS- CENT (HIGH UM-MF (COLS. ITY SOLVED SATUR- LEVEL) (COLS./ PER (NTU) (MG/L) ATION) CMG/L) 100 ML) 100 ML) NOV r 1982 03... 1020 JAN • 1983 14... 1105 MAR 17... 1000 MAY 13... 0930 AUG 17... 1220 16 235 7.2 27.5 5.7 6.4 81 240 K140 24 294 7.3 25.0 5.3 8.0 97 400 330 7.0 301 7.6 28.0 3.2 6.3 81 13 620 K170 9.4 289 8.0 29.0 3.5 7.4 97 28 600 K170 60 230 7.5 29.0 5.0 2.8 36 27 4800 4000 HARD- MAGNE- SODIUM HARD- NESS. CALCIUM SUM. SODIUM, AD- NESS NONCAR- DIS- DIS- DIS- SORP- (MG/L BONATE SOLVED SOLVED SOLVED TION AS (MG/L (MG/L (MG/L (MG/L RATIO DATE CAC03) CAC03) AS CA) AS MG) AS NA) POTAS- ALKA- SIUM, LINITY DIS- FIELD SOLVED (MG/L (MG/L AS AS K) CAC03) SULFATE DIS- SOLVED (MG/L AS 504) CHLO- FLUO- RIDE. RIDE. DIS- SOLVED SOLVED (MG/L (MG/L AS CL) AS F) NOV • 1982 03... JAN • 1983 14... 75 MAR 17... MAY 13... 110 AUG 17... 70 57 2 18 7.4 18 .9 3.2 74 15 19 .10 98 0 27 11 25 1.1 3.0 120 23 26 .20 0 17 6.7 18 1.0 2.7 73 12 17 .20 SOLIDS, SOLIDS, NITRO- SILICA. SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN.AM- BIS- CONSTI- DIS- AT 105 GEN. GEN, GEN, GEN. GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN. (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV r 1982 03... JAN I 1983 14... 24 MAR 17... MAY 13... 23 AUG 17... 25 14 .68 .020 .70 .030 .67 .70 1.4 149 9.8 16 .68 .020 .70 .030 2.5 2.50 3.2 <1 .98 .020 1.0 .030 .17 .20 1.2 210 5.3 4 .28 .020 .30 .010 .39 .40 .70 142 23.1 5 .030 <.10 .210 .59 .80 CHRO- BARIUM. CADMIUM MIUM. LEAD. MERCURY SILVER. NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN. PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CO) AS CR) AS PB) AS HG) AS SE) AS AG) NOV p 1982 03... 6.2 .220 JAN • 1983 14... 14 .450 2 100 1 10 3 .2 <1 <1 MAR 17... 5.3 .220 MAY 13... 3.1 .220 AUG 17... .180 2 200 1 <1 4 .1 <1 K = non-ideal count RIO GRANDE DE LOIZA BASIN 50061800 RIO CANOVANAS NEAR CAMPO RICO, PR 115 LOCATION.--Lat 18°19'08", long 65°53'21", Hydrologic Unit 21010005, at center pier on downstream side of bridge, on paved secondary road, 0.4 mi (0.6 km) northeast of junction of Highways 185 and 186, 1.5 mi (2.4 km) south of Campo Rico, and 4.4 mi (7.1 km) south of Loiza. DRAINAGE AREA.--9.84 sq mi (25.48 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1967 to current year. GAGE.--Water-stage recorder. Altitude of gage is 225 ft (68.6 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--16 years (1968-83), 28.2 cu ft/s (0.799 cu m/s), 38.92 in/yr (989 mm/yr), 20,430 acre-ft/yr (25.2 cu hm/yr); median of yearly mean discharges, 25 cu ft/s (0.71 cu m/s), 18,100 acre-ft/yr (22 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 15,000 cu ft/s (425 cu m/s) Sept. 13, 1982, gage height, 13.1 ft (3.993 m), from floodmarks, from rating curve extended above 350 cu ft/s (9.91 cu m/s) on basis of slope-area measurements and step-backwater analysis made in 1981; minimum daily, 0.80 cu ft/s (0.023 cu m/s) July 24, 1977. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 2,500 cu ft/s (70.8 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) July 5 1400 3,590 102 7.36 2.243 Aug. 21 1330 *6,910 196 977 2.978 Minimum discharge, 2.6 cu ft/s (0.074 cu m/s) Apr. 10, 14, 17. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 14 12 21 46 10 5.6 3.8 5.2 4.8 10 23 21 2 12 13 18 34 10 5.5 3.7 5.0 4.7 31 54 18 3 11 13 18 28 9.7 5.4 3.6 5.1 4.6 42 16 17 4 10 14 17 27 9.8 5.2 3.7 4.7 5.1 116 13 17 5 9.0 13 18 25 9.5 5.2 3.7 4.6 4.9 605 11 15 6 10 13 14 27 9.3 5.3 3.8 7.4 4.5 143 11 13 7 15 12 13 23 9.7 5.9 3.8 10 4.5 54 9.8 13 8 12 11 11 21 9.3 6.2 3.0 7.0 4.4 34 9.2 15 9 11 10 11 22 9.1 7.1 3.1 5.3 31 24 8.8 13 10 10 10 10 20 9.0 5.9 2.8 4.7 11 19 9.0 12 11 10 12 11 19 8.9 5.4 3.1 4.5 5.9 17 8.5 11 12 11 62 10 13 8.4 57 3.3 4.5 5.4 15 8.6 11 13 81 49 9.7 17 8.1 26 3.0 4.6 5.3 15 8.3 12 14 57 15 9.5 16 8.2 8.9 3.0 7.3 5.1 13 7.6 13 15 22 12 60 15 8.4 6.3 3.0 9.6 21 13 7.6 15 16 15 11 29 16 8.1 5.4 2.8 11 282 13 12 12 17 14 11 22 14 7.7 5.3 3.6 12 35 19 70 12 18 23 11 14 14 7.3 5.1 42 16 54 19 37 13 19 53 12 12 14 7.2 4.9 9.1 35 22 14 13 13 20 44 11 98 14 7.1 4.6 25 27 14 14 11 12 21 23 12 34 13 9.6 4.6 254 13 13 13 772 12 22 18 11 22 13 8.1 4.7 19 15 11 12 71 12 23 41 21 21 13 7.0 4.6 12 21 9.2 11 30 12 24 24 15 21 12 6.7 4.5 8.9 16 8.1 30 33 12 25 18 11 41 12 6.7 4.1 6.7 11 2.0 15 54 19 26 17 14 226 14 6.7 3.9 6.1 7.7 7.8 12 42 14 27 15 19 138 12 6.2 3.8 13 6.7 8.8 11 78 11 28 14 43 224 11 5.9 4.5 16 6.0 10 11 42 11 29 13 29 64 11 --- 4.4 6.9 5.7 7.7 35 30 11 30 12 43 37 11 4.3 5.6 5.4 11 13 34 20 31 14 --- 93 11 3.8 --- 5.0 --- 12 25 --- TOTAL 653.0 550 1347.2 563 231.7 233.4 481.1 303.0 623.8 1410 1559.4 412 MEAN 21.1 13.3 43.5 18.2 8.28 7.53 16.0 9.77 20.8 45.5 50.3 13.7 MAX 81 62 226 46 10 57 254 35 232 605 77' 21 MIN 9.0 10 9.5 11 5.9 3.8 2.8 4.5 4.4 10 7.6 11 CFSM 2.14 1.86 4.42 1.85 .34 .77 1.63 .99 2.11 4.62 5.11 1.39 IN. 2.47 2.03 5.09 2.13 .88 .83 1.82 1.15 2.36 5.33 5.89 1.56 AC-FT 1300 1090 2670 1123 460 463 954 601 1240 2300 3090 817 CAL YR 1982 TOTAL 9446.5 MEAN 25.9 MAX 1000 MIN 5.4 CFSM 2.63 IN 35.71 AC-FT 18740 WTR YR 1983 TOTAL 3367.6 MEAN 22.9 MAX 772 MIN 2.8 CFSM 2.33 IN 31.63 AC-FT 16600 WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 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) OCT, 21 1030 20 136 25.0 APR, 19 1345 11 181 26.0 NOV, 02 1030 13 220 24.0 MAY, 06 0812 4.6 254 25.0 DEC. 15 1020 13 239 23.0 JUN, 23 1205 182 29.0 JAN, 12 1330 18 235 24.0 JUL, 25 1045 14 167 27.0 FEB. 03 1225 9.8 265 23.0 AUG, 08 1224 9.3 223 28.5 MAR, 03 1626 5.5 246 23.5 SEP, 14 0923 12 212 25.0 117 OCEAN° AT LA NTIC 0 '0 CooeW basin RIO GRANDE 0649 0645 0638 A 0 °QUILL° 69350 062 06354 roforde Rib Grande de Loizo basin Drainage boundary 0732 07341--- LAS PIEDRAS 0777 I-.. Rib Art° A 0787 078 10 Rio Humacao basin '17:a0altmlin HUMACAO. EXPLANATION A0670 SURFACE-WATER STATION AND NUMBER A 0660 LOW-FLOW STATION AND NUMBER V0725 QUALITY-OF-WATER STATION AND NUMBER TKILOMETERS 1 6 MILES figure 19.--Northeastern rivers basin--Rio Herrera to Rio AntOn Ruiz basins. 118 RIO ESPIRITU SANTO BASIN 50063440 QUEBRADA SONADORA NEAR EL VERDE, PR LOCATION.--Lat 18°19'24", long 65°49'03", Hydrologic Unit 21010005, in Caribbean National Forest, at El Yunque, 0.55 mi (0.88 km) upstream from Rio Espiritu Santo, 0.23 mi (0.42 km) upstream from Highway 186, and about 1.2 mi (1.9 km) south of El Verde. DRAINAGE AREA.--1.01 sq mi (2.62 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March to September 1983. GAGE.--Water-stage recorder. Altitude of gage is 1,230 ft (375 m), from topographic map. REMARKS.--Records poor. EXTREMES FOR CURRENT PERIOD.--Peak discharges above base of 500 cu ft/s (14.2 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Apr. 21 0245 573 16.2 7.25 2.210 July 5 1400 586 16.6 7.28 2.219 June 17 2315 *1,210 34.3 8.35 2.545 Minimum discharge, 0.48 cu ft/s (0.014 cu m/s) Apr. 12-14. DISCHARGE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2.4 1.6 1.6 22 38 4.4 2 2.1 3.4 1.5 13 15 4.9 3 1.9 2.6 1.4 22 3.3 5.3 4 1.6 1.8 2.2 42 3.0 6.7 5 1.5 1.5 2.0 80 4.9 4.1 6 1.7 10 4.2 28 6.8 3.5 7 1.9 2.3 7.5 28 2.7 3.2 8 1.3 1.4 3.3 9.8 2.3 3.1 9 1.0 .80 8.3 7.1 2.1 3.0 10 .87 .72 2.2 5.8 2.5 3.0 11 1.6 .71 1.6 4.9 2.8 5.1 12 1.1 .91 1.3 4.5 3.0 4.5 13 .48 .77 5.5 4.1 3.0 3.0 14 .56 6.0 2.8 3.8 2.1 2.6 15 1.0 40 10 3.6 2.7 7.0 16 1.3 4.2 60 3.8 12 3.0 17 4.9 1.9 43 14 30 3.9 18 12 4.7 34 9.4 5.8 3.4 19 15 29 6.8 6.8 2.8 6.0 20 12 14 7.1 10 3.5 3.2 21 71 17 5.3 4.6 74 6.2 22 3.8 14 4.0 4.4 16 7.6 23 2.5 16 3.6 5.2 6.2 4.9 24 2.1 13 3.4 12 6.6 6.9 25 1.8 6.4 3.1 4.0 32 12 26 1.7 2.9 2.9 3.4 13 3.9 27 1.5 2.4 6.6 3.1 21 3.1 28 --- 1.6 2.1 15 3.5 14 2.0 29 3.0 2.2 2.5 3.5 21 13 1.8 30 2.7 1.5 1.9 17 5.1 7.3 4.4 31 2.6 --- 1.7 --- 4.0 6.1 --- TOTAL 155.91 208.21 270.7 397.9 357.5 140.7 MEAN 5.20 6.72 9.02 12.8 11.5 4.69 MAX 71 40 60 80 74 12 MIN .48 .71 1.3 3.1 2.1 1.8 CFSM 5.15 6.65 8.93 12.7 11.4 4.64 IN. 5.74 7.66 9.96 14.64 13.15 5.18 AC-FT 309 413 537 789 709 279 WATER-QUALITY RECORDS PERIOD OF RECORD.--APRIL TO SEPTEMBER 1983 WATER-QUALITY DATA. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 STREAMFLOW. SPECIFIC CON- TEMPERA- STREAMFLOW. SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS OUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) APR. 21 1135 18 86 21.5 JUL, 19 0950 9.1 45 23.0 MAY, 10 0947 .72 55 22.0 AUG. 09 0948 2.2 51 22.5 JUN. 15 1343 10 44 24.0 SEP, 14 1146 2.5 56 23.0 119 RIO ESPIRITU SANTO BASIN 50063500 QUEBRADA TORONJA AT EL VERDE, PR LOCATION.--Lat 18°19'43", long 65°49'14", Hydrologic Unit 21010005, in Caribbean National Forest, at downstream side of culvert on Highway 186, 0.22 mi (0.35 km) upstream from Rio Espiritu Santo, and about 0.9 mi (1.4 km) south of El Verde. DRAINAGE AREA.--0.064 sq mi (0.166 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--April to September 1983. GAGE.--Water-stage recorder and broad-V-notch crested weir. Altitude of gage is 876 ft (267 m), from topographic map. REMARKS.--Records poor. EXTREMES FOR CURRENT PERIOD.--Peak discharges above base of 50 cu ft/s (1.42 cu m/s) and maximum (*): Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) July 5 1400 *18.0 0.51 1.71 0.521 No flow for part of each day Apr. 10, 17. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .05 .04 .05 .83 1.3 .29 2 .05 .04 .05 .54 .89 .29 3 .02 .04 .04 .73 .25 .25 4 .02 .04 .07 2.7 .23 .24 5 .02 .04 .06 4.3 .24 .22 .02 .05 .20 2.4 .22 .20 7 .02 .03 .30 1.8 .15 .20 8 .02 .03 .10 .88 .13 .18 9 .02 .03 .40 .66 .12 .17 10 .01 .03 .07 .52 .12 .18 6 .01 .03 .05 .43 .13 .18 12 .01 .03 .04 .38 .12 .16 13 .01 .04 .20 .33 .12 .15 14 11 .01 .19 .10 .29 .10 .13 15 .01 1.3 .10 .27 .11 .17 16 .02 .19 1.6 .25 .14 .13 17 .06 .12 .77 .43 .46 .24 18 .24 .12 1.8 .31 .16 .47 19 .08 .57 .33 .26 .12 .19 20 .11 .42 .25 .23 .13 .24 21 1.9 .68 .21 .20 3.7 .26 22 .14 .52 .19 .19 1.1 .20 23 .09 .45 .17 .19 .47 .15 24 .09 .40 .16 .30 .41 .30 25 .05 .30 .15 .17 .97 .34 26 .05 .10 .15 .15 .55 .17 27 .05 .08 .22 .15 1.0 .13 28 .05 .07 .34 .15 .71 .09 29 .05 .08 .15 .42 .53 .08 30 .05 .06 .38 .16 .39 .14 31 --- .05 --- .15 .34 --- 3.33 6.17 8.70 20.77 15.41 6.14 TOTAL .20 .29 .67 .50 .20 MAX 1.9 1.3 1.8 MEAN .11 4.3 3.7 .47 MIN .01 .03 .04 .15 .10 .08 CFSM 1.33 3.33 4.33 11.2 3.33 3.33 IN. 1.91 3.53 4.98 11.89 8.82 3.51 AC-FT 6.6 12 17 41 31 12 WATER-QUALITY RECORDS PERIOD OF RECORD.--APRIL TO SEPTEMBER 1983 WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMgLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) APR, 21 1015 2.0 127 22.0 JUL, 19 1115 .30 100 24.0 MAY, 10 0753 .03 120 23.0 AUG, 09 0748 .13 104 23.0 JUN, 15 1155 .12 115 24.0 SEP, 14 1035 .11 118 23.5 120 RIO ESPIRITU SANTO BASIN 50063800 RIO ESPIRITU SANTO NEAR RIO GRANDE, PR LOCATION.--Lat 18°21'37", long 65°48'49", Hydrologic Unit 21010005, at left abutment, on downstream side of bridge on Highway 966, 0.1 mi (0.2 km) upstream from Quebrada Jimenez, and 1.9 mi (3.1 km) southeast of Rio Grande. DRAINAGE AREA.--8.62 sq mi (22.33 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February 1959 to April 1963 (annual low flow and occasional measurements only), August 1966 to current year. GAGE.--Water-stage recorder. Altitude of gage is 40 ft (12 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--17 years (1967-83), 57.0 cu ft/s (1.614 cu m/s), 89.80 in/yr (2,280 mm/yr), 41,300 acre-ft/yr (50.9 cu hm/yr); median of yearly mean discharges, 52 cu ft/s (1.47 cu m/s), 37,700 acre-ft/yr (46 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 11,800 cu ft/s (334 cu m/s) Oct. 26, 1978, gage height, 11.85 ft (3.612 m), from rating curve extended above 600 cu ft/s (17.0 cu m/s) on basis of step-backwater analysis; minimum, 4.0 cu ft/s (0.113 cu m/s) July 3-5, 1975, gage height 2.43 ft (0.741 m). EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 3,000 cu ft/s (85.0 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Apr. 21 0300 5,350 152 8.84 2.694 July 5 1430 5,730 162 9.06 2.761 June 16 0145 3,380 95.7 7.51 2.289 Aug. 21 Unknown 5,400 153 8.87 2.704 June 17 2400 *7,460 211 9.97 3.039 Minimum discharge, 6.0 cu ft/s (0.170 cu m/s) Apr. 10. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 27 31 56 107 14 7.7 8.1 7.9 13 191 289 40 2 19 29 74 67 13 7.5 8.3 17 13 111 188 37 3 16 54 45 40 13 7.2 7.8 13 12 151 32 40 4 15 24 67 41 13 6.9 7.7 11 13 495 25 38 5 15 62 47 99 12 7.1 7.8 8.6 16 1060 31 35 6 15 71 24 122 11 10 8.2 66 17 299 30 28 7 13 23 29 53 11 22 8.1 22 52 247 31 27 8 13 16 22 59 11 60 7.8 14 16 73 27 37 9 13 17 19 53 11 31 7.2 9.4 62 51 35 28 10 12 16 17 42 11 14 7.2 8.1 20 40 57 23 11 13 17 17 41 10 11 6.8 7.7 14 34 31 25 12 13 137 15 53 9.8 206 7.2 9.0 13 31 54 23 13 14 74 15 34 9.6 47 6.7 8.1 26 28 41 22 14 12 57 15 20 9.8 16 6.7 37 26 25 31 20 15 11 37 173 27 10 12 7.0 328 84 22 49 25 16 12 97 42 31 9.3 10 9.8 39 559 23 76 24 17 26 31 70 25 8.7 9.6 8.6 15 189 78 155 38 18 62 28 20 24 8.6 9.1 115 35 457 56 55 49 19 40 23 17 23 8.3 8.5 68 145 40 34 34 40 20 43 19 233 22 8.0 9.3 73 96 28 47 33 35 21 72 32 133 21 20 12 718 176 27 27 490 30 22 23 19 120 21 14 11 27 99 20 23 103 37 23 51 27 89 21 10 9.8 15 103 18 27 49 35 24 27 18 91 20 9.2 9.2 12 85 16 78 41 46 25 31 15 86 20 10 8.7 10 45 15 24 215 66 26 33 33 281 24 9.7 8.3 9.5 23 14 20 121 29 27 35 63 122 20 8.6 7.9 8.9 18 24 18 136 24 28 15 233 196 15 8.0 12 8.7 16 62 19 151 19 29 13 105 75 14 --- 10 10 18 17 142 94 18 30 15 109 64 16 8.6 8.7 15 117 31 78 45 31 25 --- 269 15 8.0 --- 13 --- 24 50 --- TOTAL 744 1532 2543 1195 301.6 617.9 1214.8 1507.8 2000 3529 2832 983 MEAN 24.0 51.1 82.0 33.5 10.8 19.9 40.5 48.6 66.7 114 91.4 32.8 MAX 72 238 281 122 20 206 718 328 559 1060 490 66 MIN 11 15 15 14 8.0 6.9 6.7 7.7 12 18 25 18 CFSM 2.78 5.93 9.51 4.47 1.25 2.31 4.70 5.64 7.74 13.2 10.6 3.81 IN. 3.21 6.61 10.97 5.16 1.30 2.67 5.24 6.51 8.63 15.23 12.22 4.24 AC­FT 1480 3040 5040 2370 598 1230 2410 2990 3970 7000 5620 1950 CAL YR 1982 TOTAL 21048.7 MEAN 57.7 MAX 890 MIN 6.6 CFSM 6.69 IN 90.83 AC-FT 41750 WTR YR 1983 TOTAL 19000.1 MEAN 52.1 MAX 1060 MIN 6.7 CFSM 6.04 IN 81.99 AC-FT 37690 121 RIO ESPIRITU SANTO BASIN 50063800 RIO ESPIRITU SANTO NEAR RIO GRANDE, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1958, 1961-66, 1968 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN• OXYGEN COL/- SPE- DIS- DEMAND, FORM, STREAM- CIFIC SOLVED CHEM- FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 INSTAN- DUCT- (STAND- TEMPER- BID- DIS.'. CENT (HIGH UM-MF TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 1982 1400 16 106 7.2 26.0 2.6 8.4 104 15 2400 1983 1020 14 128 7.8 23.0 1.0 8.4 98 <10 K110 1400 27 7 7.6 24.0 2.4 9.4 112 59 K820 1135 8.2 94 8.2 29.0 .80 8.0 104 17 290 1240 30 85 7.5 26.0 3.4 9.0 110 <10 4000 STREP- TOCOCCI HARD- MAGNE- SODIUM POTAS- ALKA- FECAL, HARD- NESS• CALCIUM SUM, SODIUM, AD- SIUM• LINITY SULFATE KF AGAR NESS NONCAR- DU- DIS- DIS- SORP- DIS- FIELD DIS- (COLS. (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED PER AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L DATE 100 ML) CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) NOV • 1982 8... 380 30 JAN , 1983 28... 210 39 0 8.2 4.4 8.6 .6 .4 43 <5.0 MAR 9... K1100 18 MAY 10... 3400 31 0 6.8 3.5 7.5 .6 .5 34 4.1 AUG 03... 2100 25 0 5.4 2.9 5.9 .5 .4 28 4.2 SOLIDS, SOLIDS, CHLO- FLUO- SILICA• SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- RIDE, RIDE, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, DIS- DIS- SOLVED TUENTS, SOLVED DEG. Cr NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED SOLVED (MG/L 01S- (TONS SUS- TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L DATE AS CL) AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) NOV , 1982 8... 8 (.010 (.10 <.010 JAN • 1983 28... 10 <.10 22 <1 <.010 <.10 .020 MAR 9... 6 (.010 <.10 .020 .28 MAY 10... 10 <.10 20 73 1.6 <1 .020 <.10 <.010 AUG 03... 8.8 (.10 15 59 4.8 2 <.010 <.10 .020 .08 NITRO- CHRO- GEN,AM- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, MONIA + PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL ORGANIC PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM• RECOV* TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS N) AS P) AS AS) AS BA) AS CD) AS CR) AS PS) AS HG) AS SE) AS AG) NOV , 1982 8... .70 -020 JAN , 1983 28... <.10 <.010 1 100 2 3 <1 .3 (1 2 MAR 9... .30 .020 MAY 10... (.10 .020 AUG 03... .10 .020 <1 <.1 <1 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) OCT, 06 1025 14 95 25.5 JUL, 25 1145 23 93 27.5 MAR, 04 1145 7.0 123 30.5 SEP. 15 1212 60 77 24.5 K = non-ideal count DATE NOV , 8... JAN • 28... MAR 9... MAY 10... AUG 03... 122 RIO MAMEYES BASIN 50065500 RIO MAMEYES NEAR SABANA, PR LOCATION.--Lat 18°19'46", long 65°45'04", on left bank, at bridge on Highway 988, 1.4 mi (2.3 km) west of Sabana, 2.0 mi (3.2 km) down­ stream from Rio de la Mina, and 3.2 mi (5.1 km) southeast of Mameyes. DRAINAGE AREA.--6.88 sq mi (17.8 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--August 1967 to December 1973. June to September, 1983. GAGE.--Water-stage recorder. Altitude of gage is 275 ft (83.8 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--6 years (1968-73), 59.9 cu ft/s (1.696 cu m/s), 118.23 in/yr (3,003 mm/yr), 43,400 acre-ft/yr (53.5 cu hm/yr). EXTREMES FOR CURRENT PERIOD.--Peak discharges above base of 4,000 cu ft/s (113 cu m/s) and maximum (*): Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) June 17 2315 *6,130 174 8.70 2.652 Minimum daily discharge, 24 cu ft/s (0.680 cu m/s) Aug. 8. DISCHARGE. IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 32 124 154 34 2 30 54 80 34 3 29 56 33 34 4 40 72 29 32 5 38 229 33 28 6 33 88 30 28 7 56 76 27 27 3 30 41 24 39 9 180 35 29 23 10 42 35 44 32 11 37 31 32 31 12 34 30 41 31 13 106 23 40 29 14 59 23 28 27 15 38 25 38 45 16 215 25 53 28 17 241 48 113 28 13 291 33 40 29 19 57 28 30 29 20 68 35 40 30 21 53 31 291 37 22 36 29 63 55 23 35 29 42 37 24 37 66 38 46 25 35 36 141 61 26 39 32 78 39 27 34 29 91 34 28 46 27 84 30 29 26 98 64 31 30 72 39 50 55 31 --- 31 39 --- TOTAL 2119 1568 1919 1048 MEAN 70.6 50.6 61.9 34.9 MAX 291 229 291 61 MIN 26 25 24 27 CFSM 10.3 7.36 9.00 5.07 IN. 11.46 8.48 10.37 5.67 AC-FT 4200 3110 3810 2080 WATER-QUALITY RECORDS PERIOD OF RECORD.--JUNE TO SEPTEMBER 1983 WATER-QUALITY DATA. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 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) JUN. 17 1005 53 73 25.0 AUG, 19 1213 39 121 24.5 JUL, 14 1625 27 93 26.0 SEP. 15 1212 60 77 24.5 --- --- 123 RIO MAMEYES BASIN 50065700 RIO MAMEYES AT HIGHWAY 191 AT MAMEYES, PR LOCATION.--Lat 18°22'03", long 65°46'14", Hydrologic Unit 21010005, on left bank, 0.2 mi (0.3 km) upstream from Quebrada Anon, 0.3 mi (0.5 km) downstream from Quebrada Tabonuco, and 0.3 mi (0.5 km) south of Mameyes. DRAINAGE AREA.--11.8 sq mi (30.6 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1966 to current year. GAGE.--Water-stage recorder. Altitude of gage is 22 ft (6.7 m), from topographic map. Prior to Jan. 1, 1974 at datum 4.88 ft (1.487 m) higher and Jan. 1, 1974 to Mar. 25, 1976 at datum 4.00 ft (1.219 m) higher. REMARKS.--Records poor. AVERAGE DISCHARGE.--17 years (1967-83), 73.2 cu ft/s (2.073 cu m/s), 84.24 in/yr (2,140 mm/yr), 53,030 acre-ft/yr (65.4 cu hm/yr); median of yearly mean discharges, 72 cu ft/s (2.04 cu m/s), 52,200 acre-ft/yr (64 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 26,200 cu ft/s (742 cu m/s), Oct. 24, 1974, gage height, 18.79 ft (5.727 m), present datum, from rating curve extended above 200 cu ft/s (5.66 cu m/s) on basis of slope-area measurement of peak flow; minimum, 5.0 cu ft/s (0.142 cu m/s) Apr. 28, 1975. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 5,300 cu ft/s (150 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Apr.- 21 0315 *16,200 459 17.17 5.233 June 17 2345 12,100 343 16.20 4.938 May 15 0915 5,460 155 12.96 3.950 Minimum daily discharge, 8.0 cu ft/s (0.226 cu m/s) Apr. 11. DISCHARGE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 35 59 72 111 17 9.0 10 26 39 190 262 51 2 28 60 93 88 17 9.4 12 39 36 146 199 47 3 26 89 72 58 18 14 10 24 35 123 39 51 4 26 37 63 56 21 12 10 19 49 250 33 48 5 24 119 55 115 18 15 11 18 48 604 40 45 6 23 150 39 130 18 17 12 87 40 372 38 36 7 21 44 42 63 15 23 11 38 68 327 40 34 3 20 35 37 71 15 85 10 25 36 114 34 47 9 19 53 32 74 14 46 9.0 19 226 76 45 36 10 19 41 30 54 16 19 9.0 17 42 69 73 30 11 18 34 29 53 18 20 8.0 16 33 57 39 32 12 21 206 28 68 17 385 9.0 18 31 59 69 30 13 23 118 27 43 15 99 10 58 301 46 53 28 14 29 62 26 38 16 50 9.0 140 111 41 39 26 15 23 78 176 34 18 35 10 509 169 37 63 56 16 40 150 49 39 15 29 13 62 363 37 98 31 17 41 60 69 32 14 26 12 21 426 139 202 49 18 60 61 31 31 13 25 122 190 796 99 71 63 19 45 109 28 29 13 23 86 335 114 70 43 51 20 41 44 192 28 13 21 63 163 183 57 42 45 21 75 40 249 27 51 18 1160 182 129 37 642 38 22 33 36 162 27 27 15 45 110 64 38 133 47 23 53 99 93 27 15 13 31 218 52 38 63 45 24 41 36 64 26 13 12 25 175 44 86 53 59 25 30 43 59 25 13 12 21 87 38 34 284 85 26 55 65 179 31 10 13 19 45 33 27 158 37 27 49 114 103 25 9.6 11 18 45 53 31 176 31 28 23 229 145 22 9.5 17 22 42 92 48 198 24 29 20 128 85 21 --- 11 20 60 35 258 122 23 30 26 116 170 25 12 17 39 138 77 100 58 31 59 251 21 11 38 --- 52 64 --- TOTAL 1046 2515 2750 1492 469.1 1107.4 1824.0 2865 3824 3639 3515 1283 MEAN 33.7 83.8 88.7 48.1 16.8 35.7 60.8 92.4 127 117 113 42.8 MAX 75 229 251 130 51 385 1160 509 796 604 642 85 MIN 18 34 26 21 9.5 9.0 8.0 16 31 27 33 23 CFSM 2.86 7.10 7.52 4.08 1.42 3.03 5.15 7.83 10.8 9.92 9.58 3.63 IN. 3.30 7.93 3.67 4.70 1.48 3.49 5.75 9.03 12.05 11.47 11.08 4.04 AC-FT 2070 4990 5450 2960 930 2200 3620 5680 7580 7220 6970 2540 CAL YR 1982 TOTAL 24729.0 MEAN 67.8 MAX 907 MIN 11 CFSM 5.75 IN 77.95 AC-FT 49050 WTR YR 1983 TOTAL 26329.5 MEAN 72.1 MAX 1160 MIN 8.0 CFSM 6.11 IN 83.00 AC-FT 52220 WATER-QUALITY RECORDS PERIOD OF .RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTOSER 1982 TO SEPTEMBER 1983 STREAMFLOW. SPECIFIC CON- TEMPERA- STREAMFLOW. SPECIFIC CON- TEMPERA­ DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) .(CFS) (UMMOS) (DEG C) OCT, 06 1245 23 125 27.5 APR, 19 1055 24 140 25.0 NOV. 01 1220 52 110 25.5 MAY. 06 1216 18 134 28.0 DEC. 14 1325 27 160 25.0 JUN. 17 1005 57 69 25.0 JAN. 12 1035 102 136 22.5 JUL, 14 1155 41 132 28.0 FEB. 03 0945 18 201 22.0 JUL, 25 1510 32 130 30.0 MAR, 04 1148 12 158 28.0 AUG. 19 1430 44 132 28.0 124 RIO SABANA BASIN 50067000 RIO SABANA AT SABANA, PR LOCATION.--Lat 18°19'52", long 65°43'52", Hydrologic Unit 21010005, on right bank along Highway 988, 0.3 mi (0.5 km) north of junction of Highways 988 and 983 in Sabana, and 3.3 mi (5.3 km) south of Luquillo. DRAINAGE AREA.--3.96 sq mi (10.26 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1979 to current year. GAGE.--Water-stage recorder. Altitude of gage is 260 ft (80 m), from topographic map. REMARKS.--Records fair. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 9,010 cu ft/s (255 cu m/s) Apr. 21, 1983, gage height, 19.35 ft (5.898 m), from floodmark, from rating curve extended above 200 cu ft/s (5.66 cu m/s) on basis of step-backwater analysis and slope-area measurement; minimum discharge, 0.86 cu ft/s (0.024 cu m/s) Apr. 17, 1983. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 1,500 cu ft/s (42.5 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Dec. 21 2045 1,750 49.6 12.53 3.819 May 13 1600 4,730 134 16.00 4.877 Mar. 12 1330 1,500 42.5 12.13 3.697 June 17 1830 1,840 52 12.66 3.859 Apr. 21 0315 *9,010 255 19.35 5.898 June 18 0045 2,110 60 13.06 3.981 Minimum discharge, 0.86 cu ft/s (0.024 cu m/s) Apr. 17. DISCHARGE, IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 3.8 11 10 19 4.2 1.5 1.2 22 11 97 97 13 2 3.2 13 17 15 4.1 1.3 1.2 17 10 28 49 12 3 2.9 14 13 13 3.8 1.3 1.2 7.4 9.6 18 13 12 4 2.7 6.2 13 14 3.9 1.3 1.2 5.2 12 20 12 12 5 2.9 67 11 23 3.6 1.3 1.1 7.1 8.9 96 12 11 6 3.4 35 9.2 19 3.5 2.3 1.1 5.5 9.4 53 9.9 10 7 2.4 11 8.8 12 3.7 2.9 1.0 33 9.3 41 9.1 10 8 2.4 12 8.5 12 3.2 26 1.0 12 7.9 22 8.6 11 9 2.1 27 7.9 13 3.0 8.7 .99 5.6 23 18 14 9.9 10 1.9 11 7.3 11 2.6 2.3 .96 4.4 7.6 16 22 9.3 11 1.9 12 7.1 10 2.4 1.8 .98 3.7 6.8 16 12 8.8 12 1.6 122 6.7 12 2.4 208 1.0 3.5 6.2 31 33 8.3 13 2.0 26 7.9 9.4 2.6 16 1.2 230 8C 16 18 5.4 14 8.6 10 7.0 3.7 2.7 7.2 1.8 60 38 14 11 8.0 15 2.3 20 29 9.1 2.4 4.8 1.2 153 66 13 12 11 16 8.0 20 10 3.5 2.3 3.8 1.2 23 124 13 13 8.8 17 13 10 10 7.7 1.9 3.4 12 44 243 17 23 13 18 12 10 7.2 7.6 2.0 2.9 29 120 194 13 15 14 19 6.8 50 6.9 7.0 1.9 2.4 62 151 33 12 10 11 20 8.6 12 135 6.7 1.6 2.3 14 47 40 11 10 8.3 21 15 9.2 190 6.9 8.5 2.4 545 31 27 11 199 3.7 22 6.4 8.3 38 6.5 3.0 2.0 19 24 21 11 21 9.6 23 18 77 17 6.2 2.4 2.2 11 43 19 11 14 8.2 24 12 11 12 6.0 1.9 1.3 8.7 37 17 17 12 9.7 25 6.9 9.7 12 6.0 2.7 2.1 7.4 27 16 10 53 13 26 12 14 21 6.0 2.3 1.7 6.2 19 15 9.3 22 3.9 27 11 15 16 5.4 2.0 1.6 5.6 18 24 9.1 37 8.7 28 5.2 39 17 5.0 1.8 1.9 6.4 15 26 9.2 42 7.4 29 4.5 17 16 5.2 --- 1.4 5.4 15 14 59 17 7.3 30 4.4 15 37 7.4 1.3 4.6 13 23 13 20 26 31 13 --- 59 5.0 1.3 --- 12 --- 11 14 --- TOTAL 200.9 714.4 767.5 303.3 82.4 321.2 754.63 1213.4 1141.7 735.6 854.6 317.8 MEAN 6.48 23.8 24.8 9.78 2.94 10.4 25.2 39.1 38.1 23.7 27.6 10.6 MAX 18 122 190 23 8.5 205 545 230 243 97 199 26 MIN 1.6 6.2 6.7 5.0 1.6 1.3 .96 3.5 6.2 9.1 8.6 7.3 CFSM 1.64 6.01 6.26 2.47 .74 2.63 6.36 9.87 9.62 5.99 6.97 2.68 IN. 1.89 6.71 7.21 2.85 .77 3.02 7.09 11.40 10.72 6.91 8.03 2.98 AC-FT 398 1420 1520 602 163 637 1500 2410 2260 1460 1700 630 CAL YR 1982 TOTAL 6451.80 MEAN 17.7 MAX 681 MIN 1.6 CFSM 4.47 IN 60.59 AC-FT 12800 WTR YR 1983 TOTAL 7407.43 MEAN 20.3 MAX 545 MIN .96 CFSM 5.13 IN 69.57 AC-FT 14690 WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER QUALITY DATA. OCTOBER 1982 TO SEPTEMBER 1983 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) OCT' 05 1230 4.0 113 27.0 MAY. 09 1505 5.9 111 27.5 NOV' 05 1029 7.2 118 24.0 JUN, 16 1145 122 46 25.5 DEC. 13 1252 7.2 103 23.5 JUL, 15 1453 13 139 26.5 JAN, 11 1420 11 113 23.5 JUL' 25 1350 9.6 109 27.5 FEB. 04 1300 4.0 163 24.0 AUG, 18 0950 14 91 24.5 MAR, 03 0858 1.2 146 23.5 SEP. 15 1454 9.5 100 27.0 APR. 20 1255 12 118 23.5 125 RIO FAJARDO BASIN 50071000 RIO FAJARDO NEAR FAJARDO, PR LOCATION.--Lat 18°17'56", long 65°41'42", Hydrologic Unit 21010005, on left bank off Highway 976, 0.1 mi (0.2 km) upstream from Highway 977 bridge, 0.3 mi (0.5 km) downstream from Quebrada Pen6n, 1.1 mi (1.8 km) northeast of Colonia Parafso, and 3.3 mi (5.3 km) southwest of Fajardo. DRAINAGE AREA.--14.9 sq mi (38.6 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--1960-61 (occasional low- and peak-flow measurements only), March 1961 to current year. GAGE.--Water-stage recorder. Datum of gage is 137.60 ft (41.940 m) above mean sea level. Due to flood damage, gage datum has had changes as follows: Mar. 24, 1961 to May 5, 1969, 138.95 ft (42.352 m); May 6, 1969 to Mar. 16, 1972, 135.05 ft (41.163 m); Mar. 17, 1972 to Mar 25, 1975, 138.60 ft (42.245 m). REMARKS.--Records fair. Low flow affected by diversions for water supply. AVERAGE DISCHARGE.--22 years (1962-83), 68.9 cu ft/s (1,951 cu m/s), 62.80 in/yr (1.595 mm/yr), 49,920 acre-ft/yr (61.6 cu hm/yr); median of yearly mean discharges, 69 cu ft/s, (1.95 cu m/s), 50,000 acre-ft/yr (62 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 19,600 cu ft/s (555 cu m/s), Oct. 24, 1974, gage height, 13.62 ft (4.151 m), datum then in use, from rating curve extended above 100 cu ft/s (2.83 cu m/s) on basis of step-backwater analyses and slope-area measurements of peak discharges; minimum, 1.5 cu ft/s (0.042 cu m/s) Apr. 3, May 13,14, 1977, gage height 1.57 ft (0.479 m). EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 3,500 cu ft/s (99.1 cu m/s) and maximum (*): Discharge Gage height Discharge Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Dec. 20 0230 6,290 178 9.92 3.024 May 15 0945 5,040 143 9.01 2.746 Apr. 21 0400 *15,100 428 14.82 4.517 June 17 1930 9,920 281 12.17 3.701 May 13 1630 3,880 110 8.07 2.460 Minimum discharge, 3.7 cu ft/s (0.105 cu m/s) Apr. 10,11. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 29 31 38 69 14 6.1 5.8 43 44 72 162 46 2 18 26 63 57 13 5.4 5.6 62 40 86 167 50 3 15 50 48 47 12 5.1 5.0 33 37 100 37 53 4 14 13 48 42 12 5.4 4.6 24 47 135 34 42 5 15 143 41 79 11 5.3 4.8 24 37 373 31 33 6 14 106 35 79 10 31 5.3 68 35 222 25 23 7 12 26 32 42 10 42 4.9 117 62 132 20 25 8 12 34 28 49 9.7 164 4.7 46 37 66 17 31 9 11 150 25 44 9.8 53 4.1 29 66 53 49 25 10 10 43 22 33 9.8 14 3.9 24 33 46 81 21 11 9.8 127 20 32 11 17 4.3 21 28 45 27 23 12 9.6 335 18 42 9.3 664 4.9 19 32 75 60 27 13 30 126 17 27 8.8 97 4.4 500 79 44 68 20 14 41 33 16 23 8.8 31 12 179 99 39 25 17 15 13 80 115 22 11 21 13 533 197 35 40 25 16 17 150 35 22 9.2 16 14 117 371 34 38 16 17 49 35 36 22 3.3 14 100 81 668 46 132 15 18 59 38 18 20 8.0 14 169 243 282 43 46 19 19 21 180 16 13 7.4 11 221 4C5 77 42 28 25 20 31 4'5 533 17 7.0 11 68 201 138 40 33 15 21 31 34 423 16 36 10 1500 181 69 34 496 19 22 17 30 136 15 13 9.4 90 130 55 30 86 18 23 123 265 53 17 9.3 8.9 53 2C2 46 37 55 20 24 45 41 44 16 9.7 3.2 38 211 40 69 55 17 25 21 37 38 17 10 7.9 30 126 35 31 204 87 26 40 52 238 19 8.7 7.2 25 109 27 25 175 31 27 33 56 83 16 7.5 6.9 35 103 42 23 236 21 28 22 133 209 14 7.0 7.4 59 73 37 22 260 18 29 17 63 61 13 --- 7.3 28 75 25 216 106 17 30 14 56 86 21 6.2 19 55 150 41 93 72 31 24 --- 374 18 6.1 --- 51 --- 30 58 --- TOTAL 817.4 2551 2949 968 301.3 1317.3 2541.3 4090 2935 2296 2944 376 MEAN 26.4 85.0 95.1 31.2 10.8 42.5 84.7 132 97.8 74.1 95.0 29.2 MAX 123 335 533 79 36 664 1500 538 668 373 496 87 MIN 9.6 18 16 13 7.0 5.1 3.9 19 25 22 17 15 CFSM 1.77 5.71 6.38 2.09 .73 2.85 5.69 8.86 6.56 4.97 6.38 1.96 IN. 2.04 6.37 7.36 2.42 .75 3.29 6.34 10.21 7.33 5.73 7.35 2.19 AC-FT 1620 5060 5850 1920 598 2610 5040 8110 5820 4550 5840 1740 CAL YR 1982 TOTAL 23426.0 MEAN 64.2 MAX 851 MIN 3.9 CFSM 4.31 IN 58.48 AC-FT 46470 WTR YR 1983 TOTAL 24586.8 MEAN 67.4 MAX 1500 MIN 3.9 CFSM 4.52 IN 61.38 AC-FT 48770 126 RIO FAJARDO BASIN 50071000 RIO FAJARDO NEAR FAJARDO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1960 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1982 to current year. INSTRUMENTATION.--Automatic sediment sampler since January 1983. USD-49 Sediment sampler since February 1983. REMARKS.--Automatic sediment sampler set to collect samples above a streamflow of 100 ft3/sec. In addition to automatic sediment sampler, 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. Discontinued as National Stream-Quality Accounting Network Station on September 1983 and continued operating as a regular pollution network station since that. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONS: Maximum daily mean, 1,360 mg/L April 21; Minimum daily mean, 0.0 mg/L may 9. SEDIMENT LOADS: Maximum daily, 19,800 tons (17,960 tonnes) April 21; minimum daily, 0.0 tons (0.0 tonnes) May 9. EXTREMES FOR CURRENT YEAR.-- SEDIMENT CONCENTRATIONS: Maximum daily mean, 1,360 mg/L April 21; Minimum daily mean, 0.0 mg/L May 9. SEDIMENT LOADS: Maximum daily, 19,800 tons (17,960 tonnes) April 21; minimum daily, 0.0 tons (0.0 tonnes) May 9. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- SPE- DIS- DEMAND, FORM. STREAM- CIFIC SOLVED CHEM- FECAL, FLOW. CON- PH TUR- OXYGEN, (PER- ICAL 0.7 INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF TIME TANEOUS ANCE ARO ATURE ITT SOLVED SATUR- LEVEL) (COLS./ DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) STREP- TOCOCCI FECAL. KF AGAR (COLS. PER 100 ML) NOV , 1982 17... 1525 38 106 6.7 27.0 13 8.0 101 25 X680 200 JAN . 1983 4... 1325 41 113 7.0 25.0 3.5 9.0 109 14 210 360 MAR 07... 1230 30 105 7.6 25.5 4.1 9.4 116 47 800 830 MAY 03... 1200 36 92 8.2 27.0 1.7 10.2 128 <10 250 180 JUN 02... 1215 40 126 8.2 28.0 9.8 126 AUG 02... 1345 81 81 7.4 27.0 14 9.3 117 23 2100 3200 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM, SODIUM. AD- SIUM, LINITY SULFATE RIDE, RIDE. NESS NONCAR- On- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L 80NATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV r 1982 17... 23 JAN r 1983 04... 32 2 6.8 3.6 12 1.0 .9 30 4.0 11 <.10 MAR 07... 27 MAY 03... 27 0 5.9 2.9 11 1.0 1.1 30 5.4 11 <.10 JUN 03... 38 AUG 02... 21 0 4.6 2.3 6.8 .7 1.3 22 5.4 9.1 <.10 SOLIDS, SOLIDS, NITRO- SILICA. SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEM. GEN. GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN. (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 17... 12 .18 .020 .20 .030 1.1 1.10 1.3 JAN r 1983 04... 26 82 9.0 2 <.010 .20 .030 .07 .10 .30 MAR 07... 6 .37 .030 .40 .010 .29 .30 .70 MAY 3... 23 78 7.6 <1 <.010 <.10 <.010 <.10 JUN 03... AUG 02... 17 60 13.1 14 .29 .010 .30 .040 .16 .20 .50 K . non-ideal count <.01 <.01 <.01 <.10 <.10 <1 <.01 METHYL PARA- THION, TOTAL DATE (UG/L) METHYL TRI- THU/N. TOTAL (UG/L) MIREX. TOTAL (UG/L) PARA- THION. TOTAL (UG/L) NAPH- THA- LENES. POLY- PER- TOX- TOTAL CHLOR. THANE APHENEr TRI- TOTAL TOTAL TOTAL THION (UG/L) (UG/L) (UG/L) (UG/L) JUN. 0 1983 03... <.01 RIO FAJARDO BASIN 127 50071000 RIO FAJARDO NEAR FAJARDO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHRO- BARIUM. CADMIUM MIUM. LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELF- TOTAL GEN. PHORUS. ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV 1982 17... 5.8 .030 JAN e 1983 04... 1.3 .200 1 100 2 <1 7 .5 <1 <1 MAR 07... 3.1 .030 MAY 03... .010 JUN 03... AUG 02... 2.2 .040 <1 <.1 <1 STREAMFLOW, DATE TIME INSTANTANEOUS (CFS) 46 16 10 5.6 NOV, 01 1600 DEC. 13 0955 FEB. 07 1040 MAR, 04 0918 SPECIFIC CON- DUCTANCE (UMHOS) 110 123 155 138 TEMPERA- TURE (DEG C) 27.5 23.5 25.0 25.0 STREAMFLOW, DATE TIME INSTANTANEOUS (CFS) APR, 21 1315 375 JUL, 27 1150 24 SEP. 01 1030 46.9 SPECIFIC CON- DUCTANCE (UMHOS) 142 118 106 TEMPERA- TURE (DEG C) 28.0 30.0 28.5 CHLOR- DI- PCB. ALORINe DANE. ODD. DDE, DDT, AZINONe TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN r 1983 03... 1215 <.10 <.01 <.10 <.01 <.01 <.01 <.01 LINDANE TOTAL (UG/L) DI- ELDRIN TOTAL DATE (UG/L) JUN r 1983 03... <.01 ENDO- SULFANe TOTAL (UG/L) HEPTA- HEPTA- CHLOR CHLOR, EPDXIDE TOTAL TOTAL (UG/L) (UG/L) METH- MALA- OXY- THION, CHLOR, TOTAL TOTAL (UG/L) (UG/L) ENDRIN, ETHION, TOTAL TOTAL (UG/L) (UG/L) <.10 <.01 <.01 <.01 <.01 <.01 <.01 <.01 SED. SED. SED. SED. SUSP. SUSP. SUSP. SUSP. STREAM- SEDI- FALL FALL FALL FALL FLOW. MENT, DIAM. DIAM. DIAM. DIAM. INSTAN- SUS- % FINER I FINER % FINER % FINER TIME TANEOUS PENDED THAN THAN THAN THAN DATE (CFS) (MG/L) .002 MM .004 MM .008 MM .016 MM JUN ' 1983 13... 1615 E156 2350 11 20 33 50 13... 1630 E208 2030 9 17 32 60 13... 1645 E233 2370 16 22 38 61 13... 1700 E203 2000 18 24 40 58 SED. SED. SED. SED. SED. SED. SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. FALL SIEVE SIEVE SIEVE SIEVE SIEVE DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. I FINER I FINER I FINER % FINER I FINER I FINER THAN THAN THAN THAN THAN THAN DATE .031 MM .062 MM .125 MM .250 MM .500 MM 1.00 MM JUN 13... 74 93 95 98 99 99 13... 73 94 97 98 99 99 13... 76 88 95 98 100 100 13... 82 87 94 97 99 99 E = estimate 128 RIO FAJARDO BASIN 50071000 RIO FAJARDO NEAR FAJARDO, PR--Continued WATER QUALITY DATA. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 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 29 17 1.5 31 18 1.7 38 5 .27 2 18 5 .24 26 17 1.2 63 3 .24 3 15 8 .32 50 41 13 48 17 1.4 4 14 2 .08 13 7 .34 48 1 .08 5 15 3 .12 143 196 244 41 1 .05 6 14 1 .04 106 128 94 35 2 .11 7 12 5 .16 26 14 1.1 32 7 .38 8 12 14 .45 34 29 4.6 28 14 .76 9 11 2 .06 150 206 389 25 2 .11 10 10 8 .22 43 32 6.1 22 1 .05 11 9.8 7 .19 127 153 211 20 5 .23 12 9.6 5 .13 335 374 1500 18 6 .28 13 30 30 5.4 126 134 102 17 6 .28 14 41 32 5.0 33 20 1.8 16 6 .26 15 13 19 .67 80 36 113 115 209 31,6 16 17 7 .49 150 180 140 35 26 3.3 17 49 44 18 38 58 13 36 17 1.9 18 59 54 12 38 27 2.9 18 8 .39 19 21 11 .77 180 80 17 16 10 .43 20 31 18 1.8 45 18 1.9 533 618 5060 21 31 19 2.0 34 27 2.2 423 420 2120 22 17 13 .60 30 8 .43 136 176 142 23 123 163 204 265 108 29 53 7 1.0 24 45 38 7.9 41 27 2.2 44 10 1.2 25 21 16 .91 37 44 2.4 38 5 .51 26 40 25 3.5 52 36 2.9 238 292 340 27 33 22 2.3 56 20 1.6 33 36 22 28 22 24 1.4 138 24 4.5 209 294 427 29 17 7 .32 63 23 1.9 61 37 6.9 30 14 51 1.9 56 36 2.9 86 38 33 31 24 11 .98 --- --- --- 374 559 931 TOTAL 817.4 273.95 2551 2912.67 2949 9411.13 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) CMG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) JANUARY FEBRUARY MARCH 1 69 53 9.9 14 5 .19 6.1 10 .16 2 57 7 1.1 13 5 .18 5.4 1 .01 3 47 5 .63 12 13 .42 5.1 1 .01 4 42 4 .45 12 6 .19 5.4 1 .02 5 79 121 67 11 11 .33 5.3 1 .01 6 79 44 13 10 10 .27 31 22 5.1 7 42 9 1.0 10 10 .27 42 36 18 8 49 32 6.4 9.7 13 .34 164 223 220 9 44 34 4.0 9.8 11 .29 58 46 15 10 33 19 1.7 9.8 1 .03 14 4 .15 11 32 13 1.1 11 1 .03 17 7 .42 12 42 28 3.4 9.3 4 .10 664 641 3570 13 27 13 .95 8.8 3 .07 97 128 57 14 23 11 .68 8.8 5 .12 31 32 2.7 15 22 10 .59 11 4 .12 21 40 2.3 16 22 11 .65 9.2 3 .07 16 23 1.1 17 22 10 .59 8.3 1 .02 14 23 .87 18 20 8 .43 8.0 3 .06 14 31 1.2 19 18 7 .34 7.4 2 .04 11 21 .68 20 17 6 .28 7.0 5 .09 11 23 .68 21 16 6 .26 36 311 47 10 22 .59 22 15 5 .20 13 3 .11 9.4 56 1.4 23 17 6 .23 9.3 3 .08 8.9 53 1.3 24 16 6 .26 9.7 7 .18 8.2 51 1.2 25 17 6 .28 10 2 .05 7.9 43 .95 26 19 8 .41 8.7 1 .02 7.2 21 .42 27 16 6 .26 7.5 2 .04 6.9 51 .99 28 14 4 .15 7.0 4 .08 7.4 44 .38 29 13 4 .14 --- --- 7.3 34 .68 30 21 8 .57 6.2 44 .76 31 18 8 .41 6.1 34 .83 TOTAL 968 117.41 301.3 50.79 1317.8 3905.41 129 RIO FAJARDO BASIN 50071000 RIO FAJARDO NEAR FAJARDO, PR--Continued WINTER QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 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 5.8 37 .60 43 37 10 44 16 1.9 2 5.6 25 .39 62 60 15 40 39 4.2 3 5.0 39 .54 33 12 1.1 37 9 .90 4 4.6 36 .44 24 3 .19 47 28 4.6 5 4.8 29 .38 24 4 .26 37 6 .60 6 5.3 31 .44 68 63 35 35 13 1.2 7 4.9 36 .50 117 133 67 62 29 5.2 8 4.7 34 .42 46 27 3.4 37 18 1.8 9 4.1 32 .35 29 0 .00 66 67 18 10 3.9 36 .38 24 4 .26 33 17 1.5 11 4.3 35 .40 21 4 .23 28 7 .53 12 4.9 28 .39 19 3 .15 32 7 .60 13 4.4 31 .38 500 671 3960 79 257 123 14 12 4 .16 179 326 199 99 70 23 15 18 8 .89 538 930 5740 197 276 432 16 14 7 I .36 117 65 27 371 481 615 17 100 232 1050 81 50 22 668 739 8040 18 169 277 $25 243 365 1010 282 483 670 19 221 318 405 458 1360 77 16 3.3 20 68 59 T 201 93 71 138 120 147 21 1500 1360 19800 181 192 111 69 7 1.3 22 90 29 7.0 130 135 50 55 1 .15 23 53 27 I 3.9 202 229 143 46 1 .12 24 38 35 3.6 211 293 231 40 5 .54 25 30 25 I 2.1 126 135 46 35 2 .19 26 25 17 I 1.5 109 123 62 27 18 1.3 27 35 24 5.1 103 130 45 42 31 5.3 28 59 64 117 73 8 1.6 37 25 2.7 29 28 22 1.5 75 12 2.4 25 12 .81 30 19 6 I .31 55 7 1.0 150 214 396 31 --- --- 51 12 1.7 --- --- --- TOTAL 2541.3 2206.03 4090 13216.29 2935 10502.74 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 72 65 31 162 220 457 46 11 1.4 2 86 94 28 167 186 184 50 2 .27 3 100 132 86 37 24 2.4 53 4 .57 4 135 214 145 34 25 2.3 42 1 .11 5 378 535 1720 31 13 1.1 33 7 .62 6 222 369 305 25 25 1.7 28 11 .83 7 132 74 26 20 10 .54 25 11 .74 8 66 13 2.8 17 9 .41 31 18 1.8 9 53 40 6.5 49 43 8.9 25 12 .81 10 46 4 .56 81 85 30 21 9 .51 11 45 46 5.6 27 17 1.2 23 8 .50 12 75 50 14 60 55 15 27 5 .36 13 44 20 2.4 68 65 15 20 6 .32 14 39 11 1.2 25 13 .88 17 16 .73 15 35 8 .76 40 24 3.9 25 12 .97 16 34 12 1.1 38 28 3.5 16 23 .99 17 46 10 1.2 132 156 95 15 15 .61 18 48 14 1.8 46 36 4.5 19 7 .36 19 42 9 1.0 28 6 .45 25 17 1.1 20 40 13 I 1.4 33 11 .98 15 7 .28 21 34 4 .37 496 723 2010 19 7 .36 22 30 11 .89 86 94 24 18 9 .44 23 37 6 .60 55 61 11 20 4 .22 24 69 46 11 55 50 8.8 17 2 .09 25 31 6 .50 204 290 439 87 121 74 26 25 1 .07 175 216 181 31 18 1.7 27 23 5 I .31 236 277 624 21 5 .28 28 22 10 1 .59 260 319 311 18 6 .29 29 216 314 1397 106 124 44 17 6 .28 30 41 7 .77 93 99 31 72 81 48 31 30 5 I .41 58 49 7.7 --- --- --- TOTAL 2296 p793.83 2944 4520.26 876 139.54 YEAR 24586.8 69950.05 130 RIO FAJARDO BASIN 50072500 RIO FAJARDO BELOW FAJARDO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°19'35", long 65°38'47", 1.2 mi (1.9 km) southwest of Playa de Fajardo, and 0.5 mi (0.8 km) east of Fajardo Plaza. DRAINAGE AREA.--23.4 sq mi (60.6 sq km). PERIOD OF RECORD.--Water years 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- On- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (PG/L) 100 ML) 100 ML) NOV , 1982 17... 1050 67 139 6.7 25.5 15 8.4 102 23 52000 3900 JAN , 1983 21... 1415 25 192 7.6 23.0 5.5 10.6 135 31 90000 400 MAR 11... 1335 20 184 7.6 29.5 14 8.4 111 <10 1100 MAY 06... 1435 27 157 7.5 31.0 5.0 8.8 119 14 5600 3400 AUG 5... 1440 57 151 7.5 32.0 15 9.5 130 22 K13000 2000 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- ors- SORP- On- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/"L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV r 1982 17... 26 JAN r 1983 21... 51 5 12 5.0 17 1.1 1.6 46 5.0 25 .10 MAR 11... 40 MAY 6... 47 6 12 4.2 17 1.1 1.4 41 6.5 24 .20 AUG 5... 45 3 11 4.3 14 .9 1.5 42 6.5 19 .10 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GENrAM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L ors- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENOED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV r 1982 17... 12 <.010 .20 .120 .88 1.00 1.2 JAN r 1983 21... 22 115 7.8 1 .19 .010 .20 .320 .18 .50 .70 MAR 11... 18 .18 .020 .20 .140 .26 .40 .60 MAY 6... 21 111 8.1 <1 .010 <.10 .030 .07 .10 AUG 05... 21 103 15.8 24 .18 .020 .20 .120 .28 .40 .60 CHRO- BARIUM. CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV r 1982 17... 5.3 .040 JAN , 1983 21... 3.1 .090 1 <100 1 <1 11 .3 <1 <1 MAR 11... 2.7 .070 MAY 06... .030 AUG 05... 2.7 .070 <1 100 1 5 <.1 <1 <1 K = non-ideal count RIO BLANCO BASIN 50075000 RIO ICACOS NEAR NAGUABO, PR 131 LOCATION.--Lat 18°16'38", long 65°47'09", Hydrologic Unit 21010001, in Caribbean National Forest, off Highway 191, at El Yunque, 1.6 mi (2.6 km) upstream from confluence with Rio Cubuy, 2.8 mi (4.5 km) north of Florida, and 5.3 mi (8.5 km) northwest of Naguabo Plaza. DRAINAGE AREA.--1.26 sq mi (3.26 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--July 1945 to March 1953 (operated by Puerto Rico Water Resources Authority), annual maximum, water years 1953-62, annual low-flow measurements 1962-66, October 1979 to current year. GAGE.--Water-stage recorder and broad-crested weir. Altitude of gage is 2,020 ft (616 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--11 years (1946-52, 1980-83), 15.7 cu ft/s (0.445 cu m/s), 169.21 in/yr (4,298 mm/yr), 11,370 acre-ft/yr (14.0 cu hm/yr); median of yearly mean discharges, 14 cu ft/s (0.40 cu m/s), 10,100 acre-ft/yr (12 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 2,860 cu ft/s (81.0 cu m/s) Apr. 21, 1983, gage height, 8.96 ft (2.731 m), from rating curve extended above 30 cu ft/s (0.850 cu m/s) on basis of step-backwater analysis; minimum daily, 1.5 cu ft/s (0.042 cu m/s) Mar. 22, Apr. 10, 1946. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 650 cu ft/s (18.4 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Apr. 21 0315 *2,860 81.0 8.96 2.731 July 5 1415 945 26.8 6.06 1.847 Minimum discharge, 3.1 cu ft/s (0.088 cu m/s) Apr. 26, 30. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 9.0 9.7 10 13 6.0 3.9 3.9 4.0 6.3 21 37 9.6 2 6.4 11 14 9.2 6.0 3.9 3.9 8.4 6.1 23 20 11 3 6.0 21 18 9.5 5.7 3.8 3.9 4.0 6.0 20 7.7 10 4 6.0 7.1 13 8.7 5.6 3.6 3.9 3.6 6.5 30 7.2 11 5 8.7 19 9.4 19 5.6 3.6 3.9 3.9 6.0 153 8.1 9.1 6 5.9 11 8.3 20 5.5 4.2 3.9 33 6.9 27 7.6 3.5 7 5.6 6.2 8.2 9.9 5.4 8.9 3.9 6.6 14 24 6.3 8.4 s 5.6 6.1 7.8 13 5.2 17 3.8 4.4 7.3 12 6.3 9.3 9 5.5 17 7.0 13 5.2 7.2 3.5 3.8 13 11 6.3 8.6 10 5.3 7.2 6.9 8.6 5.1 4.3 3.5 3.6 7.5 10 15 8.1 11 5.2 9.6 6.7 9.1 4.6 5.5 3.8 3.5 9.7 9.9 8.8 7.9 12 5.5 49 6.4 16 4.5 91 3.6 3.8 7.6 9.7 10 8.6 13 6.3 11 6.4 7.7 4.5 7.8 4.3 4.1 14 9.3 11 7.6 14 8.5 13 6.0 7.1 5.0 5.2 4.3 7.2 8.9 9.0 6.7 7.4 15 5.7 28 62 3.4 4.6 4.6 5.3 51 32 8.7 17 11 16 5.6 22 14 8.3 4.5 4.3 3.6 7.3 65 12 18 7.1 17 22 8.3 11 7.0 4.5 4.2 29 5.8 23 14 27 7.9 13 24 17 6.1 6.6 4.3 4.2 15 28 32 11 9.5 9.3 19 9.9 17 5.6 6.4 4.2 4.0 17 69 le 10 7.3 11 20 9.6 7.2 56 6.2 4.2 3.9 13 29 9.4 11 9.3 7.4 21 9.2 6.5 29 6.0 6.0 3.9 267 31 8.8 8.2 89 8.7 22 6.2 6.3 16 6.0 4.8 3.9 7.3 14 8.2 9.0 12 8.3 23 22 21 11 5.9 4.4 3.9 4.3 24 7.9 11 8.5 3.6 24 7.6 8.3 12 6.0 4.5 3.9 3.8 18 7.8 16 8.3 11 25 11 17 9.3 6.2 4.4 3.7 3.4 10 7.4 7.9 53 25 26 15 23 42 7.4 4.1 3.6 3.2 7.9 8.2 7.3 41 10 27 7.8 48 15 5.9 3.9 3.7 5.9 7.3 9.5 6.9 43 3.1 28 6.2 54 35 5.7 3.9 5.4 7.7 7.4 9.7 7.1 22 7.4 29 5.8 13 11 5.6 --- 4.2 3.8 3.0 7.3 38 22 7.3 30 6.5 29 22 6.3 4.0 3.3 6.4 3C 9.5 13 10 31 8.4 --- 64 6.0 4.0 --- 6.1 --- 8.5 10 --- TOTAL 272.0 524.0 549.1 277.7 136.2 239.3 446.7 424.1 396.0 565.0 567.9 283.7 MEAN 3.77 17.5 17.7 8.96 4.86 7.74 14.9 13.7 13.2 18.2 18.3 9.46 MAX 24 54 64 20 6.0 91 267 69 65 153 89 25 MIN 5.2 6.1 5.6 5.6 3.9 3.6 3.2 3.5 6.0 6.9 6.3 7.1 CFSM 6.96 13.9 14.0 7.11 3.86 6.14 11.8 10.9 10.5 14.4 14.5 7.51 IN. 8.02 15.46 16.20 8.19 4.02 7.07 13.18 12.51 11.68 16.67 16.75 8.37 AC-FT 540 1040 1090 551 270 476 886 841 795 1120 1130 563 CAL YR 1982 TOTAL 4926.8 MEAN 13.5 MAX 145 MIN 3.9 CFSM 10.7 IN 145.34 AC-FT 9770 WTR YR 1983 TOTAL 4632.2 MEAN 12.8 MAX 267 MIN 3.2 CFSM 10.2 IN 133.13 AC-FT 9290 WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTO3ER 1982 TO SEPTEMBER 1933 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS OUCTANCE TURE DATE TIME INSTANTANEOUS OUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) OCT, 05 1630 26 49 21.5 APR, 20 1035 9.7 88 20.0 NOV, 05 1400 7.5 66 21.0 MAY, 09 1211 3.9 59 21.0 DEC, 14 1040 5.3 66 20.0 JUN. 17 1220 11 51 22.0 JAN. 11 1140 8.3 60 20.0 JUL, 15 1204 8.4 95 21.0 FEB, 04 1005 5.6 78 19.5 AUG, 19 1115 7.5 80 22.0 MAR, 03 1156 4.0 66 20.0 SEP. 16 1106 6.3 61 21.5 132 RIO BLANCO BASIN 50076000 RIO BLANCO NEAR FLORIDA, PR LOCATION.--Lat 18°13'45", long 65°47'06", Hydrologic Unit 2101005, on left bank of Highway 191, 0.5 mi (0.8 km) upstream from Quebrada Sonadora, 0.7 mi (1.1 km) upstream from intersection of Highway 191 and 31, 0.8 mi (1.3 km) south of Florida. DRAINAGE AREA.--12.3 sq mi (31.9 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1982 to September 1983. GAGE.--Water-stage recorder. Altitude of gage is 50 ft (15 m), from topographic map. REMARKS.--Records fair. Low flow affected by diversion for water supply. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 3,000 cu ft/s (85.0 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Dec. 20 0230 4,370 124 17.26 5.261 July 5 1445 3,880 110 16.68 5.084 Apr. 21 0330 *11,000 312 22.76 6.937 Aug. 21 1345 3,060 86.7 15.46 4.712 Minimum discharge, 8.8 cu ft/s (0.249 cu m/s) Apr. 10. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 58 57 50 82 20 14 11 27 24 73 300 53 2 36 51 52 60 19 13 11 38 26 131 100 84 3 30 106 39 47 18 13 11 32 22 142 80 66 4 28 41 56 48 19 12 11 23 23 204 70 61 5 30 50 42 85 18 12 11 33 33 766 60 50 6 26 46 30 91 17 23 11 125 23 204 50 45 7 25 26 39 53 17 50 11 85 43 136 40 43 8 24 25 30 73 16 112 10 37 38 69 35 43 9 23 65 26 54 16 4B 10 24 77 50 60 42 10 23 34 25 43 16 21 9.6 24 55 44 160 47 11 22 34 22 44 16 32 13 21 32 41 60 43 12 21 203 20 68 15 492 10 17 63 43 140 43 13 77 56 19 34 16 60 9.7 23 27 41 70 41 14 48 27 17 34 18 27 15 35 41 39 50 36 15 48 77 232 39 17 22 20 282 159 36 80 47 16 31 99 51 47 15 20 14 80 371 36 70 36 17 77 41 51 35 15 18 75 66 106 63 194 37 18 162 97 23 32 15 17 102 116 167 56 74 45 19 40 96 21 30 15 16 99 234 62 48 51 45 20 109 33 405 28 14 15 34 135 46 60 65 36 21 89 25 118 27 26 14 1220 158 46 40 610 43 22 39 23 85 26 18 14 96 91 30 35 98 44 23 148 136 76 25 15 14 42 206 31 38 61 52 24 61 57 91 24 15 13 38 153 31 105 63 69 25 44 57 92 23 18 13 31 75 30 45 214 91 26 64 110 346 26 16 13 27 76 41 37 181 50 27 46 202 154 23 15 12 154 74 35 35 248 37 28 34 186 230 21 14 25 98 42 43 44 152 37 29 28 65 69 21 --- 18 40 46 27 400 128 36 30 30 176 84 24 14 26 31 109 80 74 68 31 43 --- 332 21 12 --- 26 --- 60 58 --- TOTAL 1564 2301 2977 1292 469 1199 2320.3 2440 1861 3201 3696 1470 MEAN 50.5 76.7 96.0 41.7 16.8 38.7 77.3 78.7 62.0 103 119 49.0 MAX 162 203 405 91 26 492 1220 282 371 766 610 91 MIN 21 23 17 21 14 12 9.6 17 22 35 35 36 CFSM 4.11 6.24 7.81 3.39 1.37 3.15 6.29 6.40 5.04 8.37 9.68 3.98 IN. 4.73 6.96 9.00 3.91 1.42 3.63 7.02 7.38 5.63 9.68 11.18 4.45 AC-FT 3100 4560 5900 2560 930 2380 4600 4840 3690 6350 7330 2920 WTR YR 1983 TOTAL 24790.3 MEAN 67.9 MAX 1220 MIN 9.6 CFSM 5.52 IN 74.97 AC-FT 49170 WATER-QUALITY RECORDS PERIOD OF RECORD.--OCTOBER 1982 TO SEPTEMBER 1983 WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- OATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMMOS) (DEG C) (CFS) (UMNOS) (DEG C) OCT, 21 1345 107 83 26.0 MAR, 02 1340 13 115 28.0 NOV' 09 1159 23 107 27.5 MAY, 10 1307 25 105 29.0 DEC, 21 1240 65 93 23.5 JUN, 21 1600 47 -- 28.0 JAN, 13 1020 39 107 21.5 JUL. 26 1040 34 101 27.0 FEB, 07 1305 17 172 26.0 SEP, 01 1300 52 100 28.0 Rib Anton Rui. basin MACAO Drainage boundary-\ 820 Rio Grand• di Loira basin Rib de la Plato basin Island divide.\ Drainage boundary 0872. Rib Salinas (Nigua} basin t EXPLANATION 0820 SURFACE-WATER STATION AND NUMBER 0825 LOW-FLOW STATION AND NUMBER V0835 QUALITY-OF-WATER STATION AND NUMBER M A R CARIBE • 31 WELL AND WELL NUMBER 2 2 4 5 6 TKILOMETERS I I S MILES Figure 20.--Southeastern rivers basin--Rio Humacao to Rio Seco basins. 134 RIO HUMACAO BASIN 50082000 RIO HUMACAO AT HIGHWAY 3 AT HUMACAO, PR LOCATION.--Lat 18°08'49", long 65°49'37", at bridge on Highway 3, 300 ft (91 m) downstream from Quebrada Mariana, and 0.4 mi (0.6 km) south of Humacao. DRAINAGE AREA.--17.3 sq mi (44.8 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1982 to September 1983. GAGE.--Water-stage recorder and concrete control. Datum of gage 33.33 ft (10.16 m) above mean sea level. REMARKS.--Records fair. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 2,000 cu ft/s (56.6 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Nov. 19 0345 3,780 107 11.97 3.648 Aug. 17 0545 2,840 80.4 11.27 3.435 Apr. 21 0445 2,720 77.0 11.17 3.405 Aug. 21 1715 8,810 249 14.56 4.438 July 5 1700 *9,940 282 15.00 4.572 Minimum discharge, 10 cu ft/s (0.283 cu m/s) many days in March and April. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 74 87 190 40 27 14 11 21 23 41 53 56 2 56 64 101 40 23 13 12 41 23 84 78 83 3 47 55 68 31 21 15 10 31 22 64 49 61 4 43 49 66 35 22 14 11 28 29 102 48 50 5 43 161 59 42 22 14 12 37 27 1470 43 50 6 41 155 50 41 20 14 11 31 26 194 42 47 7 39 74 47 33 20 15 11 34 26 116 39 51 3 37 71 45 36 19 13 11 26 20 90 41 49 9 36 51 45 62 19 25 11 25 39 68 46 51 10 34 52 43 43 18 16 11 22 31 55 41 52 11 34 55 44 34 18 22 11 21 25 52 35 55 12 33 59 40 36 17 130 11 22 68 47 34 54 13 45 45 41 37 17 37 12 22 27 44 37 41 14 41 39 41 30 16 15 13 26 25 45 45 41 15 34 42 45 29 16 13 12 73 86 42 40 55 16 28 69 39 23 15 13 11 35 136 59 83 47 17 58 56 38 27 15 13 18 83 53 102 391 43 18 66 92 36 30 16 14 47 36 100 71 109 47 19 153 412 36 29 16 12 13 34 43 48 68 40 20 147 153 40 28 14 12 17 37 33 38 61 43 21 79 76 46 29 14 12 336 25 36 35 1760 72 22 72 74 42 28 14 13 37 27 37 35 151 54 23 65 149 37 23 14 12 25 40 33 45 107 52 24 49 71 36 28 16 13 24 274 34 74 100 118 25 47 72 35 28 15 13 23 75 34 37 138 125 26 45 52 52 32 14 12 23 67 33 33 124 102 27 43 58 46 27 13 12 24 35 85 32 98 64 28 93 73 57 26 13 11 42 31 47 35 110 55 29 49 52 49 26 --- 11 28 27 40 232 87 48 30 78 347 43 26 12 28 25 37 97 76 54 31 108 --- 105 27 11 --- 24 --- 123 60 --- TOTAL 1817 2870 1662 1016 484 571 866 1335 1278 3610 4194 1760 MEAN 58.6 95.7 53.6 32.8 17.3 18.4 28.9 43.1 42.6 116 135 58.7 MAX 153 412 190 62 27 130 336 274 136 1470 1760 125 MIN 28 39 35 26 13 11 10 21 20 32 34 40 CFSM 3.39 5.53 3.10 1.90 1.00 1.06 1.67 2.49 2.46 6.71 7.80 3.39 IN. 3.91 6.17 3.57 2.13 1.04 1.23 1.36 2.87 2.75 7.76 9.02 3.78 AC-FT 3600 5690 3300 2020 960 1130 1720 2650 2530 7160 8320 3490 WTR YR 1983 TOTAL 21463 MEAN 58.8 MAX 1760 MIN 10 CFSM 3.40 IN 46.15 AC- FT 42570 135 RIO HUMACAO BASIN 50082000 RIO HUMACAO AT HIGHWAY 3 AT HUMACAO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°08'49", long 65°49'37", at bridge on Highway 3, 300 ft (91 m) downstream from Quebrada Mariana, and 0.4 mi (0.6 km) south of Humacao plaza. DRAINAGE AREA.--17.3 sq mi (44.8 sq km). PERIOD OF RECORD.--Water years 1958-66, 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW. CON- PH TUR- OXYGEN. (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- 8ID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV r 1982 22... 1225 51 234 7.0 25.0 16 7.3 89 42 K130000 29000 JAN . 1983 21... 1100 28 282 7.1 25.5 6.5 9.0 109 26 260000 41000 MAR 11... 1000 29 274 7.6 26.0 65 6.8 0 <10 54000 K16000 APR 21... 1100 E257 146 25.0 21... 1105 E254 146 25.0 21... 1110 -- 146 25.0 21... 1115 E244 146 25.0 21... 1120 E231 -- -- MAY 06... 1110 31 235 7.7 27.0 75 6.8 86 18 270000 11000 AUG 05... 1040 45 236 7.4 29.0 16 7.6 98 29 K84000 26000 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO-• HARD- NESS, CALCIUM STUN, SODIUM. AD- SIUMr LINITY SULFATE RIDE. RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1982 22... 68 JAN . 1983 21... 82 0 22 6.5 24 1.2 2.0 83 12 26 .20 MAR 11... 50 APR 21... 21... -- -- -- 21... 35 8 9.2 2.8 13 1.0 3.6 13 15 <.10 21... -- -- -- 21... -- MAY 06... 77 0 21 5.9 24 1.2 2.3 77 14 25 .20 AUG 05... 73 0 20 5.6 21 1.1 1.7 74 9.7 22 .20 SOLIDS, SOLIDS, NITRO- SILICA. SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN.AM- DIS- CONSTI- DIS- AT 105 GEN, GIN. GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS. SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV . 1982 22... 32 .68 .020 .70 .260 .14 .40 1.1 JAN r 1983 21... 39 181 13.7 1 .85 .050 .93 .440 .46 .90 1.8 MAR 11... 100 .04 .060 .10 .23C .97 1.20 1.3 APR 21... 21... -- 21... 19 92 21... -- 21... MAY 06... 35 174 14.5 104 .61 .090 .70 .39C .51 .90 1.6 AUG 05... 33 163 19.6 57 .73 .070 .80 .250 .55 .80 1.6 K = non-ideal count E = estimate 136 RIO HUMACAO BASIN 50082000 RIO HUMACAO AT HIGHWAY 3 AT HUMACAO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL SEDI- GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- MENT, TOTAL TOTAL T3TAL EPABLE ERASLE ERABLE ERA3LE ERAELE TOTAL ERABLE SUS- (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENDED DATE AS NO3) AS P) AS AS) AS FA) AS CD) AS CR) AS PS) AS HG) AS SE) AS AG) (MG/L) NOV , 1932 22... 4.9 .170 JAN 193' 21... 8.0 .310 2 <100 1 1 12 .3 <1 <1 MAR 11... 5.8 .370 APR 21... 863 21... 815 21... 21... 788 21... -- 15400 MAY 06... 7.1 .380 AUG 05... 7.1 .300 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURF DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMMOS) (DEG C) (CFS) (UMMOS) (DEG C) OCT, 21 1530 86 193 29.0 JUN, 21 1152 37 -- 29.5 DEC, 21 0955 44 268 23.5 JUL, 26 0855 34 243 28.0 FES, 08 0930 19 312 23.0 SEP, 06 1110 53 234 29.5 MAR, 02 1627 14 303 31.0 137 RIO GUAYANES BASIN 50083500 RIO GUAYANES AT YABUCOA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°03'33", long 65°54'03", at bridge on Highway 182, 1.4 mi (2.2 km) west-northwest of Yabucoa plaza. DRAINAGE AREA.--17.2 sq mi (44.6 sq km). PERIOD OF RECORD.--Water years 1958-62, 1968-70, 1980 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 DATE SPE- STREAM- CIFIC FLOW, CON- PH INSTAN- DUCT- (STAND- TIME TANEOUS ANCE ARD (CFS) (UMHOS) UNITS) OXYGEN, OXYGEN COLI- STREP- DIS- DEMAND, FORM, TOCOCCI SOLVED CHEM- FECAL, FECAL, HARD- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. (MG/L ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER AS (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CAC03) NOV • 1982 18... 1050 104 120 6.5 24.0 88 7.6 90 22 22000 45000 JAN e 1983 27... 1220 43 158 7.5 24.0 15 7.8 93 <10 2200 K1900 44 MAR 22... 1400 21 164 7.5 28.0 5.4 7.2 92 <10 K1400 5100 MAY 18... 1240 32 136 7.4 26.0 24 7.8 97 60 K1200 3800 44 JUN 03... 1240 30 166 7.4 28.0 7.3 100 AUG 22... 1045 139 106 7.2 26.0 8.4 103 4100 9500 HARD- NESS, NONCAR- 80NATE (MG/L DATE CAC03) CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, SODIUM, AD- SIUM. LINITY SULFATE - RIDE, RIDE, DIS- DIS- SORP- Dn."' FIELD DIS- DIS- DIS- SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS AS NA) AS K) CAC03) AS SO4) AS CL) AS F) 5IO2) NOV , 1982 18... JAN •1983 27... 0 11 MAR 22... MAY 13... 0 11 JUN 03... AUG 22... 32 3.9 14 1.0 1.4 56 <5.0 11 .10 36 62 4.1 15 1.0 1.4 54 7.2 11 .10 37 61 34 SOLIDS, SOLIDS, NITRO- SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN.AM- CONSTI- ,DIS- AT 105 GEN. GEN, GEN, GEN, GEN, MCNIA + NITRO- NITRO- TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEN, DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) DAY) CMG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) NOV • 1982 18... JAN r 1983 27... MAR 22... MAY 13... JUN 03... AUG 22... 162 .46 .040 .50 .070 1.2 1.30 1.8 8.0 7 <.010 .40 .080 .12 .20 .60 2.7 13 <.010 .20 .020 .28 .30 .50 2.2 119 10.3 28 <.010 .30 .060 .14 .20 .50 2.2 .25 .050 .30 .030 .27 .30 .60 2.7 K = non-ideal counts SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) SEDI- MENT, SUS- PENDED CMG/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SELE- NIUM, TOTAL (UG/L AS SE) RIO GUAYANES BASIN 50083500 RIO GUAYANES AT YABUCOA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 138 PHOS- PHORUS, TOTAL (MG/L DATE AS P) CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY TOTAL TOTAL TOTAL TOTAL TOTAL ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) NOV , 1982 18... .150 JAN r 1983 27... .070 1 100 5 1 <1 .3 <1 2 MAR 22... .030 MAY 18... .080 JUN 03... AUG 22... .100 219 61 CHLOR- DI- PCB, ALORIN, DANE, DOD, DOE, DDT, AZINON, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN , 1983 03... 1240 <.10 <.01 <.10 <.01 <.01 <.01 <.01 HEPTA- METH- DI- ENDO- HEPTA- CHLOR PALA- OXY- ELDR IN SULFAN, ENDRIN, ETHIONe CHLOR, EPDXIDE LINDA NE THION, CHLOR, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (US/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN r 1983 03... <.01 <.10 <.01 <.01 <.31 <.01 <.01 <.01 <.01 DATE METHYL PARA- THION, TOTAL (UG/L) METHYL TRI- THION, TOTAL (UG/L) MIREX, TOTAL (UG/L) PARA- THION, TOTAL (UG/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) PER- THANE TOTAL (UG/L) TOX- APHENE, TOTAL (UG/L) TOTAL TRI- THICN (UG/L) JUN , 1983 03... <.01 <.01 <.01 <.01 <.10 <.10 <1 <.01 SED. SED. SEC. SED. SED. SED. BED SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. MAT. STREAM- FALL FALL FALL FALL FALL FALL FALL FLOW, DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. INSTAN- X FINER % FINER X FINER % FINER X FINER % FINER X FINER TIME TANEOUS THAN THAN THAN THAN THAN THAN THAN DATE (CFS) 002 MM .004 MM .003 MM .016 MM .031 MM .062 MM .004 MM JAN r 1983 27... 1220 43 0 0 0 0 0 0 0 BED 3ED BED BED BED BED BED BED MAT. MAT. MAT. MAT. MAT. MAT. MAT. MAT. FALL SIEVE SIEVE SIEVE SIEVE SIEVE SIEVE SIEVE DIAM. DIAM. DIAN. DIAM. DIAM. DIAM. DIAM. DIAM. X FINER % FINER % FINER % FINER X FINER % FINER X FINER % FINER THAN THAN THAN THAN THAN THAN THAN THAN DATE .062 MM .062 MM .125 4M .250 MM .500 MM 1.00 MM 2.00 MM 4.00 MM JAN 27... 0 0 1 5 19 47 73 93 139 RIO GUAYANES BASIN 50086500 RIO GUAYANES ABOVE MOUTH AT PLAYA DE GUAYANES, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°03'45", long 65°49'42", at old railroad crossing, 0.2 mi (0.3 km) from mouth, 0.4 mi (0.6 km) west of Playa de Guayanes, and 3.5 mi (5.6 km) northeast of Yabucoa Plaza. DRAINAGE AREA.--34.0 sq mi (88.1 sq km). PERIOD OF RECORD.--Water years 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL. HARD- FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS INSTAN- DUCT.. (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER AS DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CAC03) NOV , 1982 18... 1330 154 144 6.9 25.0 96 7.2 87 <10 30000 9800 JAN r 1983 27... 1025 62 167 7.6 23.0 14 7.8 91 10 K1500 K1800 47 MAR 22... 1135 31 189 7.8 30.0 9.4 3.0 106 <10 470 K110 MAY 18... 0945 121 145 7.3 26.5 35 7.0 37 43 45000 59000 41 AUG 22... 1400 425 113 7.0 28.0 95 8.0 102 24 5400 9800 28 HARD- MAGNE- SODIUM POTAS- ALKA- CHID- FLUO- SILICA, NESS, CALCIUM SIUMr SODIUM, AD- STUN, LINITY SULFATE RIDE, RIDE, ors- NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- SOLVED BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS DATE CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) SI02) NOV , 1982 18... 39 JAN , 1983 27... 0 12 4.2 16 1.0 1.7 56 6.0 14 .10 35 MAR 22... 70 MAY 18... 0 10 4.0 17 1.2 4.4 43 17 16 .10 28 AUG 22... 0 7.2 2.5 10 .8 2.5 30 10 10 <.10 21 SOLIDS, SOLIDS. NITRO- SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MCNIA + NITRO- NITRO- TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN. GEN, DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/I) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) NOV , 1982 18... 161 .47 .030 .50 .080 1.6 1.70 2.2 9.7 JAN . 1983 27... 123 20.5 11 .49 .010 .50 .070 <.10 MAR 22... 22 .19 .010 .20 .060 .44 .50 .70 3.1 MAY 18... 122 39.9 77 .28 .020 .30 .060 .24 .30 .60 2.7 AUG 22... 81 93.1 109 .23 .070 .30 .040 .36 .40 .70 3.1 K = non-ideal count 140 RIO GUAYANES BASIN 50086500 RIO GUAYANES ABOVE MOUTH AT PLAYA DE GUAYANES, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHRO— SEDI— BARIUM, CADMIUM MIUM. LEAD. MERCURY SILVER, MENTe PHOS— TOTAL TOTAL TOTAL TOTAL TOTAL SELE— TOTAL SEDI— OIS— PHORUSe ARSENIC RECOV— RECOV— RECOV— RECOV— RECOV— NIUMe RECOV— MENTe CHARGE, TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE SUS— SUS— (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENDED PENDED DATE AS P) AS AS) AS BA) AS CD) AS CR) AS P3) AS HG) AS SE) AS AG) (MG/L) (T/DAY) NOV 1982 18... .100 207 86 JAN e 1983 27... .070 1 100 6 <1 <1 .5 <1 2 MAR 22... .050 MAY 18... .190 AUG 22... .150 1 <100 1 <10 5 <.1 <1 <1 SED. SED. SED. SED. SED. SED. BED SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. MAT. STREAM— FALL FALL FALL FALL FALL FALL FALL FLOW, DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. INSTAN— X FINER X FINER X FINER X FINER X FINER X FINER X FINER TIME TANEOUS THAN THAN THAN THAN THAN THAN THAN DATE (CFS) 002 MM .004 MM .008 MM .016 MM .031 MM .062 MM .004 MM JAN , 1983 27... 1025 62 0 0 0 0 0 0 0 BED BED BED BED BED BED BED BED MAT. MAT. MAT. MAT. MAT. MAT. MAT. MAT. FALL SIEVE SIEVE SIEVE SIEVE SIEVE SIEVE SIEVE DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. X FINER 1 FINER X FINER X FINER X FINER X FINER X FINER % FINER THAN THAN THAN THAN THAN THAN THAN THAN DATE .062 MM .062 MM .125 MM .250 MM .500 MM 1.00 MM 2.00 MM 4.00 MM JAN 27... 0 0 1 3 16 55 86 97 RIO MAUNABO BASIN 50090500 RIO MAUNABO AT LIZAS, PR 141 LOCATION.--Lat 18°01'38", long 65°56'24", Hydrologic Unit 21010005, on right bank, off Highway 759 at Lizas, about 1.0 mi (1.6 km) below Quebrada Coroco, and about 3.0 mi (4.8 km) northwest of Maunabo. DRAINAGE AREA.--5.38 sq mi (13.93 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February 1971 to current year. GAGE.--Water-stage recorder. Altitude of gage is 230 ft (70.1 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--12 years (1972-831 18.7 cu ft/s (0.530 cu m/s), 47.20 in/yr (1,199 mm/yr), 13,550 acre-ft/yr (16.7 cu hm/yr); median of yearly mean discharges, 16 cu ft/s (0.45 cu m/s), 11,600 acre-ft/yr (14 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 6,280 cu ft/s (178 cu m/s) Aug. 31, 1979, gage height, 14.57 ft (4.441 m), from rating curve extended above 50 cu ft/s (1.42 cu m/s) on basis of step-backwater analysis; minimum daily, 2.2 cu ft/s (0.062 cu m/s) Jul. 16, Aug. 7, 13, 1974. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 600 cu ft/s (17.0 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Nov. 18 2230 1,110 31.4 7.99 2.435 July 4 1845 *1,550 43.9 8.83 2.691 Nov. 30 0300 618 17.5 6.77 2.063 Aug. 16 2030 1,240 35.1 8.26 2.518 Minimum discharge, 2.5 cu ft/s (0.071 cu m/s) Apr. 16, 17. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 19 17 23 21 7.6 5.6 3.3 4.4 7.2 12 31 28 2 16 13 21 16 7.5 5.5 3.3 6.4 6.9 35 29 44 3 15 12 19 15 7.4 5.2 3.1 6.8 6.6 36 23 31 4 14 12 19 16 7.5 5.1 3.3 6.3 7.1 97 24 27 5 21 14 16 18 7.4 5.0 3.3 8.4 7.4 73 34 24 6 13 11 14 23 7.0 5.4 3.4 7.1 11 79 23 23 7 12 11 14 17 7.0 6.4 3.2 5.9 7.6 61 19 22 8 12 13 13 17 6.8 11 3.0 4.8 6.5 31 18 21 9 12 13 13 23 6.7 14 2.9 4.5 23 25 17 20 10 12 14 12 18 6.7 6.2 2.7 4.4 9.0 22 17 19 11 11 13 12 16 6.5 6.0 2.8 4.1 7.6 20 17 20 12 10 14 12 15 6.2 6.7 2.6 4.3 6.7 21 25 25 13 10 13 11 14 6.1 6.6 2.9 4.1 8.2 17 35 19 14 10 10 11 14 7.2 5.7 2.9 6.4 8.3 16 23 17 15 10 11 12 13 6.9 5.6 3.2 7.8 33 15 23 17 16 11 15 11 15 6.5 5.3 2.6 6.2 61 15 102 17 17 18 11 10 12 6.5 5.1 4.4 21 19 41 127 17 18 19 70 9.6 9.6 6.7 5.0 27 20 77 26 43 17 19 14 79 9.4 9.4 6.2 4.9 7.0 50 17 21 26 15 20 37 32 9.8 9.1 6.0 4.7 11 13 13 13 24 17 21 18 17 11 9.0 6.3 4.6 54 7.1 11 17 139 25 22 15 13 12 9.0 6.0 4.6 11 11 9.9 16 47 19 23 54 16 12 9.1 5.8 4.5 6.7 83 9.2 46 33 26 24 19 13 16 9.0 6.4 4.3 5.3 93 8.8 39 28 20 25 16 11 15 9.2 6.5 4.0 4.6 25 8.2 18 54 22 26 16 11 17 9.3 6.2 3.7 4.6 16 8.1 15 40 110 27 14 11 18 3.7 6.2 3.5 4.2 13 19 15 38 53 28 13 11 17 8.2 5.8 3.8 5.7 10 15 15 56 26 29 12 46 16 8.2 --- 3.6 5.5 9.1 9.4 85 37 25 30 14 214 16 3.6 3.3 4.8 9.0 23 26 43 46 31 17 --- 58 7.9 3.3 --- 3.5 --- 22 31 --- TOTAL 504 766 479.8 407.8 185.6 168.2 204.3 485.6 464.7 995 1226 812 MEAN 16.3 25.5 15.5 13.2 6.63 5.43 6.81 15.7 15.5 32.1 39.5 27.1 MAX 54 214 58 23 7.6 14 54 98 77 97 139 110 MIN 10 10 9.4 7.9 5.8 3.3 2.6 4.1 6.5 12 17 15 CFSM 3.03 4.74 2.88 2.45 1.23 1.01 1.27 2.92 2.88 5.97 7.34 5.04 IN. 3.48 5.30 3.32 2.82 1.28 1.16 1.41 3.36 3.21 6.83 8.48 5.61 AC-FT 1000 1520 952 309 368 334 405 963 922 1970 2430 1610 CAL YR 1982 TOTAL 6403.5 MEAN 17.5 MAX 214 MIN 6.1 CFSM 3.25 IN 44.27 AC-FT 12700 WTR YR 1983 TOTAL 6699.0 MEAN 18.4 MAX 214 MIN 2.6 CFSM 3.42 IN 46.31 AC-FT 13290 WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 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) OCT, 13 1250 11 156 23.5 APR, 20 1245 12 189 23.0 NOV, 08 1405 11 188 26.5 MAY, 12 1221 4.4 177 23.5 DEC, 22 1400 11 245 26.0 JUN, 22 1105 10 152 29.0 JAN. 18 1235 9.6 297 25.5 JUL, 13 1025 17 167 27.0 FEB, 11 1030 6.7 233 22.0 JUL, 28 1335 14 167 29.0 MAR, 01 1212 7.0 152 27.0 AUG, 02 1325 25 151 29.0 MAR, 02 1116 5.7 175 27.0 142 RIO MAUNABO BASIN 50091000 RIO MAUNABO AT MAUNABO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°00'24", long 65°54'19", at bridge on Highway 3, 0.4 mi (0.6 km) southwest of Maunabo plaza, and 1.3 mi (2.1 km) upstream from mouth. DRAINAGE AREA.--12.4 sq mi (32.1 sq km). PERIOD OF RECORD.--Water years 1958-66, 1975 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI-• STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEW.. FECAL, FECAL, HARD." FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS INSTAN- DUCT- (STAND- TEMPER- BID- On- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARC ATURE ITV SOLVED SATUR- LEVEL) (COLS./ PER AS DATE (CFS) (UMMOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CAC03) NOV e 1982 19... 1500 120 129 6.4 24.0 63 7.0 33 10 9200 14000 JAN r 1983 27... 1425 15 241 7.6 27.0 2.5 3.5 107 <10 8000 K1400 72 MAR 23... 1225 6.8 234 7.8 31.0 4.0 3.2 111 13 K200 K400 MAY 19... 1210 15 198 7.6 29.5 11 7.9 104 <10 3700 2200 69 AUG 23... 1100 69 194 7.4 27.0 2.0 3.2 102 58 4200 2800 58 HARD- NESS, NONCAR- BONATE (MG/L DATE CAC03) CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM, DIS- SOLVED (MG/L AS NA) SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, AD- SIUM, LINITY SULFATE RIDE, RIDE, DIS- SORP- DIS- FIELD DIS- DIS- DIS- SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS AS K) CAC03) AS 504) AS CL) AS F) SI02) NOV , 1982 19... JAN 1983 27... 0 17 MAR 23... MAY 19... 0 16 AUG 23... 0 14 27 7.2 20 1.1 1.0 84 10 16 .10 38 89 7.0 21 1.1 1.1 75 12 19 .20 37 5.5 17 1.0 1.1 61 10 15 <.10 35 SOLIDS, SOLIDS, SUM OF SOLIDS, RESIDUE NITRO- NITRO- CCNSTI- DIS- AT 105 GEN, GEN' TUENTS, SOLVED DEG. Cr NITRATE NITRITE DIS- (TONS SUS- TOTAL TOTAL SOLVED PER PENDED (MG/L (MG/L DATE (MG/L) DAY) (MG/L) AS N) AS N) NITRO- NITRO- NITRO- NITRO- GEN'AM- GEN, GEN, GEN, MONIA + NO2+NO3 AMMONIA ORGANIC ORGANIC TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L (MG/L AS N) AS N) AS N) AS N) NITRO- GEN, TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS NO3) NOV r 1982 19... 96 .57 .030 JAN • 1983 27... 160 6.3 <1 <.010 MAR 23... 16 .010 MAY 19... 158 6.4 6 <.010 AUG 23... 134 25.0 32 .38 .020 K = non-ideal count .60 .070 1.1 1.20 1.8 8.0 .30 .040 <.10 <.10 .010 .09 .10 .20 .070 .23 .30 .50 2.2 .40 .030 .17 .20 .60 2.7 RIO MAUNABO BASIN 50091000 RIO MAUNABO AT MAUNABO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHRO- SEDI- BARIUM, CADMIUM MIUM. LEAD, MERCURY SILVER, MENT, PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL SEDI- DIS- PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM. RECOV- MENT, CHARGE, TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE SUS.. SUS- (MG/L (UG/L (UG/L (UG/L (UG/L (US/L (UG/L (UG/L (UG/L PENDED PENDED DATE AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) (MG/L) (T/DAY) NOV , 1982 19... .140 148 48 JAN 1983 27... .040 2 100 4 <1 <1 .3 <1 2 MAR 23... .050 MAY 19... .070 AUG 23... .100 1 100 1 <10 5 <.1 <1 <1 SED. SED. SED. SED. SED. SED. BED SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. MAT. STREAM- FALL FALL FALL FALL FALL FALL FALL FLOW, DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. INSTAN- X FINER X FINER X FINER I FINER X FINER X FINER X FINER TIME TANEOUS THAN THAN THAN THAN THAN THAN THAN DATE (CFS) 002 MM .004 MM .008 MM .016 MM .031 MM .062 MM .004 MM JAN r 1983 27... 1425 15 0 0 0 0 0 0 0 BED BED BED BED BED BED BED BED MAT. MAT. MAT. MAT. MAT. MAT. MAT. MAT. FALL SIEVE SIEVE SIEVE SIEVE SIEVE SIEVE SIEVE DIAM. DIAM. DIAM. HAM. DIAM. DIAM. DIAM. DIAM. X FINER I FINER X FINER I FINER X FINER I FINER X FINER X FINER THAN THAN THAN THAN THAN THAN THAN THAN DATE .062 MM .062 MM .125 MM .250 MM .500 MM 1.00 MM 2.00 MM 4.00 MM JAW 27... 0 0 1 3 24 62 71 91 143 NITRO- GEN, TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS NO3) 144 RIO CHICO BASIN 50091800 RIO CHICO AT PROVIDENCIA, PR WATER-QUALITY RECORDS LOCATION.--Lat 17°59'16", long 66°00'18", at flat low bridge 200 ft (61 m) south of Highway 3, 0.5 mi (0.8 km) above mouth, and 1.5 mi (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 1982 TO SEPTEMBER 1983 SPE- STREAM- CIFIC FLOW. CON- PH INSTAN- DUCT- (STAND- TIME TANEOUS ANCE ARD DATE (CFS) (UMHOS) UNITS) OXYGEN, OXYGEN COLI STREP- DIS- DEMAND, FORM, TOCOCCI SOLVED CHEM- FECAL, FECAL, HARD- TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR NESS TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. (MG/L ATURE ITY SOLVED SATUR-• LEVEL) (COLS./ PER AS (DEG C) (NTU) (MG/L) ATION) CMG/L) 100 ML) 100 ML) CAC03) NOV , 1982 19... 1215 68 177 6.8 24.0 65 7.4 88 14 56000 30000 19... 1500 -- -- -- -- -- -- -- JAN , 1983 27... 1615 1.3 635 7.4 27.0 2.4 .0 0 71 2800000 430000 130 MAR 23... 1025 .53 773 7.4 29.0 .0 0 140 K6700000 K220000 MAY 19... 0930 .68 632 7.4 28.0 5.1 .0 0 100 K6300000 990000 130 AUG 23... 1300 19 278 7.6 23.0 11 7.2 92 20 420000 52000 80 HARD- NESS, CALCIUM NONCAR- DIS- BONATE SOLVED (MG/L (MG/L DATE CAC03) AS CA) MAGNE- SODIUM STUN, SODIUM, AD- DIS- DIS- SORP- SOLVED SOLVED TION (MG/L (MG/L RATIO AS MG) AS NA) POTAS- ALKA- CHLO- FLUO- SILICA, SIUM, LINITY SULFATE RIDE. RIDE, On- DIS- FIELD DIS- ors- DIS- SOLVED SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L (MG/L AS (MG/L (MG/L (MG/L AS AS K) CAC03) AS 504) AS CL) AS F) SI02) NOV , 1982 19... 19... JAN • 1983 27... 0 29 MAR 23... MAY 19... 0 32 AUG 23... 0 18 51 13 70 2.8 4.1 190 58 50 .80 33 220 12 78 3.1 6.5 210 69 87 .20 34 8.6 28 1.4 1.2 92 13 22 .10 33 SOLIDS, SOLIDS, NITRO- SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + TUENTS. SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) NOV • 1982 19... <1 .74 .060 .30 .310 1.3 1.60 2.4 11 19... JAN .1983 27... 372 1.3 <1 .020 <.10 6.20 .10 6.30 MAR 23... 12 .030 <.10 14.0 ' 1.0 15.0 MAY 19... 445 .82 12 .030 <.10 8.40 8.6 17.0 AUG 23... 179 9.2 11 .36 .040 .40 .510 .59 1.10 1.5 6.6 CHRO- SEDI- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, MENT, PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL SERI- DIS- PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- MENT, CHARGE, TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE SUS- SUS- (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENDED PENDED DATE AS P) AS AS) AS BA) AS CO) AS CR) AS P3) AS HG) AS SE) AS AG) (MG/L) (T/DAY) NOV • 1982 19... .260 19... JAN ,1933 27... 2.20 MAR 23... 3.30 MAY 19... 2.70 AUG 23... .240 2 100 4 <1 <1 .5 <1 4 1 <100 1 <10 <.1 <1 <1 103 19 148 -- K = non-ideal count 145 RIO GRANDE DE PATILLAS BASIN 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) up­ stream from Lago Patillas Dam and 2.2 mi (3.5 km) northwest of Patillas. DRAINAGE.--18.3 sq mi (47.4 sq km). 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. Altitude of gage is 235 ft (71.6 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--17 years (1967-83), 60.9 cu ft/s (1.725 cu m/s), 45.19 in/yr (1,148 mm/yr), 44,120 acre-ft/yr (54.4 cu hm/yr); median of yearly mean discharges, 61 cu ft/s (1.728 cu m/s), 44,200 acre-ft/yr (54 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 14,800 cu ft/s (419 cu m/s) Sept. 16, 1975, gage height, 12.45 ft (3.795 m), from rating curve extended above 250 cu ft/s (7.08 cu m/s) on basis of slope-area measurement of peak flow; minimum, 4.6 cu ft/s (0.130 cu m/s) May 13-16, 1968, gage height, 3.55 ft (1.082 m). EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 2,500 cu ft/s (70.8 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) June 16 0500 3,190 90.3 9.11 2.777 July 04 1945 *3,820 108 9.63 2.935 Minimum discharge, 10 cu ft/s (0.283 cu m/s) Apr. 16, 17. DISCHARGE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 156 99 231 61 21 16 12 19 46 54 138 59 2 115 57 109 55 20 15 12 25 44 87 158 72 3 70 44 83 51 19 15 12 24 43 110 96 65 4 54 50 74 49 21 15 12 22 42 429 79 53 5 51 67 67 73 22 14 12 22 45 337 122 4B 6 41 49 55 78 20 21 12 30 113 258 94 44 7 37 43 47 65 20 18 11 26 57 235 76 42 8 34 46 44 61 19 22 11 21 47 144 75 40 9 31 72 41 109 19 28 11 19 69 104 77 39 10 29 63 39 68 19 19 11 19 51 86 76 36 11 27 113 37 57 19 17 11 18 44 72 67 36 12 26 146 35 55 19 92 11 17 41 67 62 42 13 80 238 35 50 19 33 11 17 47 61 66 36 14 36 98 33 46 20 21 11 22 70 55 60 36 15 26 71 41 44 20 20 11 24 243 49 62 38 16 27 63 37 41 19 18 10 22 1030 49 143 43 17 54 56 32 39 17 17 13 25 253 53 305 41 18 50 148 31 38 17 17 60 79 384 60 161 34 19 48 317 31 37 17 15 22 107 160 57 99 31 20 125 355 36 35 17 15 52 94 110 56 77 40 21 97 188 32 32 19 15 241 57 88 45 352 227 22 59 101 32 31 17 15 52 56 74 39 165 79 23 229 95 29 30 17 14 33 141 66 207 105 79 24 74 74 29 30 17 14 26 332 60 221 85 74 25 46 59 30 30 17 14 23 141 55 78 92 80 26 37 50 30 37 17 14 21 85 51 57 90 113 27 32 49 30 29 16 13 20 66 74 48 73 79 28 43 54 30 27 16 13 22 57 58 95 124 58 29 35 76 30 25 --- 13 20 50 50 322 81 50 30 50 332 36 24 13 18 55 55 131 73 70 31 95 --- 144 23 13 --- 49 --- 103 64 --- TOTAL 1914 3273 1590 1430 520 599 804 1741 3570 3769 3397 1784 MEAN 61.7 109 51.3 46.1 18.6 19.3 26.8 56.2 119 122 110 59.5 MAX 229 355 231 109 22 92 241 332 1030 429 352 227 MIN 26 43 29 23 16 13 10 17 41 39 60 31 CFSM 3.37 5.96 2.80 2.52 1.02 1.06 1.46 3.07 6.50 6.67 6.01 3.25 IN. 3.89 6.65 3.23 2.91 1.06 1.22 1.63 3.54 7.26 7.66 6.91 3.63 AC-FT 3800 6490 3150 2340 1030 1190 1590 3450 7080 7480 6740 3540 CAL YR 1982 TOTAL 22902 MEAN 62.7 MAX 839 MIN 15 CFSM 3.43 IN 46.55 AC-FT 45430 WTR YR 1983 TOTAL 24391 MEAN 66.8 MAX 1030 MIN 10 CFSM 3.65 IN 49.58 AC-FT 48380 146 RIO GRANDE DE PATILLAS BASIN 50092000 RIO GRANDE DE PATILLAS NEAR PATILLAS, 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 1982 TO SEPTEMBER 1983 OXYGEN, COLI- STREP- SPE.' DIS- FORM. TOCOCCI HARD- STREAM- CIFIC SOLVED FECAL, FECAL, HARD- NESS, FLOW, CON- PH TUR- OXYGEN, (PER- 0.7 KF AGAR NESS NONCAR- INSTAN- DUCT- (STAND- TEMPER... BID- DIS- CENT UM-MF (COLS. (MG/L BONATE TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- (COLS./ PER AS (MG/L DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) 100 ML) 100 ML) CAC03) CAC03) OCT r 1932 06... 1235 43 168 8.1 26.0 1.1 8.4 105 320 K190 44 0 FEB r 1983 03... 1430 19 158 7.8 24.0 1.3 9.5 114 100 430 52 0 JUN 09... 1255 140 114 7.8 26.0 33 8.0 99 K12000 9500 AUG 02... 1315 131 113 7.5 26.0 11 3.6 106 220 340 33 0 CALCIUM DIS- SOLVED (MG/L DATE AS CA) MAGNE- SIUM. DIS- SOLVED (MG/L AS MG) SODIUM. DIS- SOLVED (MG/L AS NA) SOLIDS, SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, RESIDUE AD- SIUM, LINITY SULFATE RIDE, RIDE, DIS- AT 180 SORP- DIS- FIELD DIS- DIS- DIS- SOLVED DEG. C TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L ()IS- RATIO (MG/L AS (MG/L (MG/L (MG/L AS SOLVED AS K) CAC03) AS SO4) AS CL) AS F) SI02) (MG/L) OCT r 1982 06... 9.8 4.8 13 .9 <.1 52 11 11 .10 26 112 FEB , 1983 03... 12 5.3 15 .9 .4 52 11 9.6 .20 23 88 JUN 09... .6 36 8.6 9.6 .20 76 AUG 2... 7.5 3.4 10 .8 .4 33 8.4 9.6 <.10 21 79 SOLIDS, NITRO- NITRO- NITRO- NITRO- PHOS- PHOS- SUM OF SOLIDS, GEN' GEN. GEN, GEN,AM- PHOS- PHORUS. PRATE, CONSTI- DIS- NO2+NO3 AMMONIA AMMONIA MONIA + PHOS- PHDS- PHORUS, ORTHO. ORTHO, TUENTS, SOLVED DIS- DIS- DIS- ORGANIC PHORUS. PHORUS DIS- DIS- OIS- DIS- (TONS SOLVED SOLVED SOLVED TOTAL TOTAL TOTAL SOLVED SOLVED SOLVED SOLVED PER (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE CMG/L) DAY) AS N) AS N) AS NH4) AS N) AS P) AS PO4) AS P) AS P) AS PO4) OCT e 1982 06... 13.0 <.10 .020 .03 1.20 <.010 <.010 <.010 FEB . 1983 3... 108 4.5 .10 .020 .03 .70 .030 .09 .020 .010 .03 JUN 09... 28.6 .10 .020 .03 .50 .050 .15 .030 .010 .03 AUG 2... 81 27.9 .19 .040 .05 .30 .030 .09 .080 .020 .06 ALUM- BERYL- CHRO- INUM, ARSENIC BARIUM, LIUM , CADMIUM MIUM, COBALT, COPPER, IRON, LEAD, LITHIUM DIS- DIS- DIS- 015- DIS- DIS- DIS- DIS- DIS- DIS- DIS- SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS AL) AS AS) AS BA) AS BE) AS CO) AS CR) AS CO) AS CU) AS FE) AS PS) AS LI) OCT , 1932 06... 1 17 <1 <1 <1 <3 2 31 <1 <4 FEB r 1983 3... 10 1 16 <1 <1 <1 <3 5 28 1 <4 JUN 09... 10 1 <1 5 <1 AUG 02... 300 K = non-idoal count 1 15 <1 <1 <1 <3 9 100 4 <4 147 RIO GRANDE DE PATILLAS BASIN 50092000 RIO GRANDE DE PATILLAS NEAR PATILLAS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 SEDI- MANGA- MOLY8- SELF- STRON- VANA- MENT, NESE, MERCURY DENUM, NICKEL. NIUM, SILVER, TIUM, DIUM. ZINC. SEDI- DIS- DIS- On- DIS- OIS- DIS- DIS- OIS- DIS- DIS- MENT, CHARGE, SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SUS- SUS- (UG/L (UG/L (UG/L (UG/L (UG/L (UG/1 (UG/L (UG/L (UG/L PENDED PENDED DATE AS MN) AS HG) AS MO) AS NI) AS SE) AS AG) AS SR) AS V) AS ZN) CMG/L) (T/DAY) OCT ' 1982 06... 10 <.1 <10 1 <1 <1 35 <6.0 <4 1 .12 FEB , 1983 03... 8 .3 <10 3 <1 <1 36 <6.0 15 5 .26 JUN 09... <.1 <1 <1 <1 73 28 AUG 02... 10 <.1 <10 3 <1 <1 27 <6.0 <3 12 4.2 STREAMFLOW. SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURF (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) NOV, 10 1510 54 135 27.5 MAY, 13 0722 17 164 25.5 DEC. 27 1025 31 214 21.5 JUL, 12 1220 67 152 28.0 MAR, 02 0814 16 173 23.5 JUL, 2i-.. 1540 58 142 29.5 APR, 05 1245 12 155 25.0 SEP. 13 1132 36 154 27.0 SED. SUSP. STREAM- SEDI- SIEVE FLOW, MENT, DIAM. INSTAN- SUS- 2 FINER TIME TANEOUS PENDED THAN DATE (CFS) (MG/L) .062 MM OCT . 1982 06... 1235 43 1 100 FEB , 1983 03... 1430 19 5 80 JUN 09... 1255 140 73 85 AUG 02... 1315 131 12 92 Rib Grande de Manoti basin AIBONITO N Rib tie la Plato basin • • \ r• • CAYEY E Riblnabob basin j• Logo Guayabal COAMO Drainage boundary Drainage boundary ,;?IUAN DIAZ • • 88 Coamo 1030 1020 SALIN S 8 Canal si GOAYAMA Bahra de Jobos SAN JUAN MAR CAR1BE EXPLANATION A1007 LOW-FLOW STATION AND NUMBER V1065 QUALITY-OF-WATER STATION AND NUMBER • 1 WELL AND WELL NUMBER 150 RIO COAMO BASIN 50106500 RIO COAMO NEAR COAMO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°03'52", long 66°22'10", on Highway 153 bridge, 0.4 mi (0.6 km) above Rio de la Mina, and 1.75 mi (2.8 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 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLT- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 01... 1040 6.7 595 7.8 27.0 2.0 4.2 54 24 K860 770 JAN , 1983 25... 0910 5.5 678 7.7 23.5 <1.0 5.3 63 48 K65000 8200 MAR 29... 1235 4.0 670 8.0 28.5 <1.0 3.6 112 10 430 400 MAY 09... 1115 16 615 8.1 27.5 1.5 8.4 108 26 5700 430 AUG 15... 1035 7.4 603 8.2 30.0 1.7 9.5 127 28 K830 260 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS 504) AS CL) AS F) NOV , 1982 01... 220 JAN , 1983 25... 260 0 66 22 42 1.2 3.2 260 33 45 .20 MAR 29... 250 MAY 09... 230 1 61 19 36 1.1 3.4 230 32 41 .20 AUG 15... 250 21 66 21 37 1.1 3.0 231 32 44 .20 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO-. NITRO- GEN,AM- On- CONSTI- On- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDEO (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE St02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982b 01... 6 2.4 .180 2.6 .130 .57 .70 3.3 JAN .0, 1933 25... 32 399 5.9 <1 1.4 .230 1.6 1.60 .10 1.70 3.3 MAR 29... 2 2.4 .370 2.6 .470 .43 .90 3.7 MAY 09... 31 362 15.6 <1 1.8 .290 2.1 .390 .31 .70 2.8 AUG 15... 33 375 7.5 2 2.6 .150 2.7 .120 .48 .60 3.3 CHRO- SARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERA3LE ERASLE ERABLE ERABLE ERABLE TOTAL ERABLE DATE (MG/L AS NO3) (MG/L AS P) (UG/L AS AS) (UG/L AS BA) (UG/L AS CD) (UG/L AS CR) (UG/L AS PB) (UG/L AS HG) (UG/L AS SE) (UG/L AS AG) NOV , 1982 01... 15 JAN , 1983 25... 15 MAR 29... 16 MAY 09... 12 AUG 15... 15 .670 1.30 .900 .580 .580 1 2 <100 100 1 1 <1 2 11 7 .2 <.1 <1 <1 <1 <1 K = non-ideal count Rib Grande de Arecibo basin Island divide Rib Grande de Masco basin Drainage boundary Drainage boundary,. Rib Guonojibo basin? ..4c, L Logo SABANA GRANDE 41 o LOCO as JUANA DIAZ Logo Bronco GUAYANIILA 146 141 Bohl° di Guoyonillo elofteb de To/lobo° 1297 PLAYA DE ­PONCE ENSENADA GUANICA EXPLANATION A1125 SURFACE—WATER STATION AND NUMBER M A R CARIBE A1159 CREST—STAGE GAGING STATION A1220 LOW—FLOW STATION AND NUMBER V1140 QUALITY—OF—WATER STATION AND NUMBER • 74 WELL AND WELL NUMBER Map area Figure 22.--South coast rivers basin--Rio Inabon to Rio Loco basins. 152 RIO INABON BASIN 50112500 RIO INABON AT REAL ABAJO, PR LOCATION.--Lat 18°05'10", 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 sq mi (25.12 sq km). 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. Altitude 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. AVERAGE DISCHARGE.--17 years (1965-69, 72-83), 18.6 cu ft/s (0.527 cu m/s), 26.04 in/yr (661 mm/yr), 13,480 acre-ft/yr (16.6 cu hm/yr); median of yearly mean discharges, 18 cu ft/s (0.51 cu m/s), 13,000 acre-ft/yr (16 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 7,000 cu ft/s (198 cu m/s) Sept. 16, 1975, gage height, 18.6 ft (5.669 m) from flood- mark, from rating curve extended above 30 cu ft/s (0.850 cu m/s) on basis of contracted opening and flow-over-road measurements of peak flow; minimum daily, 0.80 cu ft/s (0.023 cu m/s) July 23, 1977. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 500 cu ft/s (14.2 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Mar. 12 1400 *691 19.6 8.24 2.512 May 22 1600 675 19.1 8.10 2.469 May 18 1445 663 18.8 8.00 2.438 Minimum daily discharge, 1.4 cu ft/s (0.040 cu m/s) Mar. 7. DISCHARGE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 36 13 14 7.6 5.0 2.4 2.1 8.4 11 9.1 6.2 9.9 2 22 11 12 7.2 5.0 2.0 2.1 9.1 10 9.1 7.8 10 3 14 10 11 6.9 4.6 1.8 2.1 10 16 8.8 6.7 9.4 4 12 9.0 11 7.4 4.3 1.8 2.5 12 15 13 5.7 9.1 5 11 8.2 10 7.5 4.0 1.8 2.8 9.2 11 13 5.3 9.2 6 10 11 10 3.6 3.7 1.6 3.5 8.2 12 12 5.5 8.1 7 11 8.9 10 3.1 4.0 1.4 2.5 8.1 11 12 5.1 8.0 8 11 20 9.7 3.0 3.8 2.0 2.2 7.8 9.9 13 7.8 7.7 9 10 35 9.2 9.2 3.7 5.0 2.1 7.4 9.8 11 9.1 6.7 10 9.1 31 8.9 7.9 3.9 4.2 2.0 6.6 1C 11 9.3 5.9 11 7.8 21 8.7 7.8 3.2 2.5 2.2 6.0 10 12 6.4 5.7 12 8.0 41 8.7 8.1 2.8 92 2.6 5.1 9.3 11 5.0 10 13 18 46 9.9 8.3 2.8 25 2.8 6.4 10 10 5.0 5.8 14 18 27 10 9.0 3.4 12 3.1 10 9.9 10 4.7 4.8 15 17 29 10 9.3 3.8 8.0 14 10 17 9.6 4.5 7.1 16 44 28 11 3.2 3.1 6.1 13 13 107 9.7 4.0 6.8 17 26 21 8.8 7.3 3.3 4.8 9.3 10 91 11 17 9.3 13 16 21 8.2 7.1 3.4 4.1 22 61 88 11 12 13 19 14 19 7.9 6.8 2.9 3.5 7.6 53 49 9.3 5.8 14 20 10 17 8.1 6.6 3.1 3.3 35 30 33 7.7 4.3 6.2 21 11 15 7.8 5.8 3.2 3.1 126 34 26 8.5 16 5.2 22 11 28 7.5 5.7 2.3 2.6 40 81 22 7.9 14 14 23 15 47 7.0 5.8 2.1 2.5 22 44 21 8.1 7.2 13 24 13 25 6.9 5.7 2.3 2.4 18 22 19 10 5.5 7.5 25 10 20 7.0 5.7 3.3 3.4 13 22 18 8.4 4.5 9.0 26 8.1 17 7.3 5.3 3.6 2.9 10 22 17 8.4 10 13 27 7.8 15 9.9 5.8 2.6 2.0 16 17 16 6.5 18 6.0 28 20 14 7.6 5.7 2.5 2.0 20 14 13 6.6 21 3.8 29 24 13 11 5.4 --- 1.8 12 13 11 6.8 15 3.3 30 18 19 13 5.7 2.5 8.0 13 9.7 7.0 12 3.0 31 15 --- 8.5 5.2 2.4 --- 12 --- 6.2 12 --- TOTAL 477.8 640.1 290.6 219.7 95.7 212.9 420.5 585.3 712.6 297.7 272.4 249.5 MEAN 15.4 21.3 9.37 7.09 3.42 6.87 14.0 18.9 23.8 9.60 8.79 8.32 MAX 44 47 14 9.3 5.0 92 126 81 107 13 21 13 MIN 7.8 8.2 6.9 5.2 2.1 1.4 2.0 5.1 9.3 6.2 4.0 3.0 CFSM 1.59 2.20 .97 .73 .35 .71 1.44 1.95 2.45 .99 .91 .86 IN. 1.83 2.45 1.11 .84 .37 .82 1.61 2.24 2.73 1.14 1.04 .96 AC-FT 948 1270 576 436 190 422 834 1160 1410 590 540 495 CAL YR 1982 TOTAL 4735.1 MEAN 13.0 MAX 266 MIN 2.0 CFSM 1.34 IN 18.16 AC-FT 9390 WTR YR 1983 TOTAL 4474.8 MEAN 12.3 MAX 126 MIN 1.4 CFSM 1.27 IN 17.16 AC-FT 8880 WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 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) --- 153 RIO BUCANA BASIN 50114000 RIO CERRILLOS NEAR PONCE, PR LOCATION.--Lat 18°04'15", long 66°34'51", Hydrologic Unit 21010004, on right bank off Highway 139, 2.3 mi (3.7 km) upstream from Quebrada Ausubo and 4.6 mi (7.4 km) northeast of Plaza Degetau in Ponce. DRAINAGE AREA.--17.8 sq mi (46.1 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February to April 1964 (monthly measurements only), May 1964 to current year. GAGE.--Water-stage recorder. Datum of gage is 253.10 ft (77.145 m) above mean sea level, datum of 1929. Prior to Mar 22, 1977, at site 0.15 mi (0.24 km) upstream and datum 9.90 ft (3.018 m) higher. REMARKS.--Records fair. Some low-flow regulation by construction upstream. AVERAGE DISCHARGE.--19 years (1965-83), 35.8 cu ft/s (1.014 cu m/s), 27.31 in/yr (694 mm/yr), 25,940 acre-ft/yr (32.0 cu hm/yr); median of yearly mean discharges, 33 cu ft/s (0.93 cu m/s), 23,900 acre-ft/yr (29 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 22,400 cu ft/s (634 cu m/s) Sept. 16, 1975, gage height, 11.2 ft (3.41 m), from flood- marks, from rating curve extended above 150 cu ft/s (4.25 cu m/s) on basis of slope-area measurement of peak flow; minimum, 2.2 cu ft/s (0.062 cu m/s) May 28, 1967. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 1,200 cu ft/s (34.0 cu m/s) and maximum (*): Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Apr. 21 0445 *821 23.2 7.04 2.146 Minimum discharge, 5.6 cu ft/s (0.158 cu m/s) Mar. 20. DISCHARGE., IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 54 26 35 16 9.9 9.2 6.8 22 32 35 13 18 2 47 24 31 15 9.7 8.9 6.9 20 31 32 13 16 3 32 22 30 14 9.7 8.6 6.8 21 34 27 13 14 4 27 21 29 14 9.9 3.3 6.7 27 32 44 12 13 5 24 19 27 14 10 8.3 7.1 28 27 40 11 14 6 22 29 25 14 9.8 8.5 7.5 22 30 32 11 12 7 19 23 24 15 9.7 8.2 7.3 21 27 28 10 12 3 19 30 23 14 9.5 7.9 7.0 19 27 27 14 14 9 18 50 22 15 10 11 6.7 18 26 25 17 12 10 17 51 22 14 11 12 6.5 17 30 26 18 11 11 16 43 21 14 10 9.4 6.6 15 35 28 12 13 12 15 69 21 12 10 119 7.2 21 27 26 10 20 13 31 89 20 12 9.9 43 7.5 18 23 25 12 13 14 23 4? 22 12 9.7 17 20 22 22 24 15 11 15 18 41 21 13 10 12 66 23 34 22 14 11 16 58 53 22 13 10 9.8 58 25 124 22 12 12 17 38 67 19 13 9.8 9.0 24 25 120 24 49 18 18 30 88 18 12 9.5 8.5 66 63 149 22 33 53 19 36 72 18 12 9.2 8.2 33 91 92 21 20 34 20 28 56 19 12 8.8 7.6 115 52 62 19 17 18 21 27 50 18 10 9.1 7.4 206 69 52 13 34 14 22 30 76 17 10 9.3 7.6 68 113 45 16 33 22 23 53 103 16 10 9.1 7.6 75 105 39 15 21 25 24 60 63 16 11 9.0 7.3 66 69 35 18 18 18 25 34 51 16 10 9.4 7.8 42 61 32 16 17 22 26 25 43 16 11 9.7 7.9 33 58 37 17 34 24 27 21 38 16 11 9.7 7.1 39 48 39 15 40 16 28 52 37 16 10 9.3 7.1 40 43 41 15 25 14 29 57 34 20 10 --- 7.1 30 38 38 15 20 12 30 40 47 30 10 6.9 24 36 37 16 21 12 31 32 --- 18 11 7.1 --- 33 --- 14 24 TOTAL 1003 1469 668 384 270.7 415.3 1095.6 1243 1379 724 613 518 MEAN 32.4 49.0 21.5 12.4 9.67 13.4 36.5 40.1 46.0 23.4 19.8 17.3 MAX 60 108 35 16 11 119 206 113 149 44 49 53 MIN 15 19 16 10 8.8 6.9 6.5 15 22 14 10 11 CFSM 1.82 2.75 1.21 .70 .54 .75 2.05 2.25 2.58 1.32 1.11 .97 IN. 2.10 3.07 1.40 .80 .57 .87 2.29 2.60 2.38 1.51 1.28 1.08 AC-FT 1990 2910 1320 762 537 824 2170 2470 2740 1440 1220 1030 CAL YR 1982 TOTAL 10788.9 MEAN 29.6 MAX 450 MIN 6.0 CFSM 1.66 IN 22.55 AC-FT 21400 WTR YR 1983 TOTAL 9782.6 MEAN 26.8 MAX 206 MIN 6.5 CFSM 1.51 IN 20.44 AC-FT 19400 OCT, 19 1040 DEC. 07 1225 FEB. 08 1145 APR, 13 1030 32 246 25 230 9.6 234 7.4 332 JUN, 14 0950 22 JUL' 07 0820 28 SEPe 02 1320 16 260 27.0 282 26.0 257 30.0 32.0 24.5 26.0 28.0 154 RIO BUCANA BASIN 50114000 RIO CERRILLOS NEAR PONCE, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1964 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN. OXYGEN COLI- STREP- SPE- DIS- DEMAND. FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL. FECAL. FLOW, CON- PH TUR- OXYGEN. (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARO ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) 1982 1230 24 285 8.1 27.0 1.1 7.5 96 11 K800 940 1983 1120 13 306 23.0 70 9.0 106 460 1000 1600 6.9 285 8.4 29.5 7.0 7.4 98 <10 K150 530 0830 23 275 7.9 23.5 63 3.9 106 16 K790 3600 1420 14 264 8.4 30.9 3.3 3.0 107 16 290 270 HARD- MAGNE- SODIUM POTAS-. ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SUM, SODIUM. AD- SIUMr LINITY SULFATE RIDE. RIDE, NESS NONCAR- DIS- On- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1982 02... 120 JAN , 1933 11... 130 0 42 7.0 11 .4 1.4 18 7.8 .10 MAR 29... 130 MAY 06... 120 4 39 6.5 12 .5 1.1 120 17 7.8 <.10 AUG 15... 120 6 38 6.5 11 .5 1.1 116 17 8.1 <.10 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN. MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDEO (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE 5IO2) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 02... 4 <.010 .60 <.010 .40 1.0 JAN , 1933 11... 22 205 7.2 109 .47 .030 .50 .080 .72 .80 1.3 MAR 29... 4 .010 <.10 .010 <.10 MAY 06... 22 177 11.0 96 .37 .030 .40 .040 .16 .20 .60 AUG 15... 23 174 6.4 14 <.010 .20 <.010 .10 .30 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER. NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS. ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS 3A) AS CD) AS CR) AS P3) AS HG) AS SE) AS AG) NOV r 1982 02... 4.4 .050 JAN r 1983 11... 5.8 .410 1 100 1 7 6 <.1 <1 MAR 29... .050 MAY 06... 2.7 .080 AUG 15... 1.3 .080 2 100 1 2 3 <.1 <1 <1 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOWe SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS OUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) NOV , 02... JAN ' 11... MAR 29... MAY 06... AUG 15... K = non-ideal count 155 RIO PORTUGUES BASIN 50115000 RIO PORTUGUES NEAR PONCE, PR LOCATION.--Lat 18°04'45", long 66°38'01", Hydrologic Unit 21010004, on right bank 30 ft upstream from bridge on Highway 504, 0.2 mi (0.3 km) upstream from small unnamed tributary, 4.4 mi (7.1 km) upstream from Rio Chiquito, and 4.7 mi (7.6 km) north of Plaza Degetau in Ponce. DRAINAGE AREA.--8.82 sq mi (22.84 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February to June 1964 (monthly measurements only), July 1964 to current year. GAGE.--Water-stage recorder. Altitude 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. Some low-flow regulation due to unknown activity upstream. AVERAGE DISCHARGE.--19 years (1965-83), 18.2 cu ft/s (0.515 cu m/s), 28.02 in/yr (712 mm/yr), 13,190 acre-ft/yr (16.3 cu hm/yr); median of yearly mean discharges, 18 cu ft/s (0.51 cu m/s), 13,000 acre-ft/yr (16 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 13,100 cu ft/s (371 cu m/s) Sept. 16, 1975, gage height, 10.1 ft (3.08 m), from flood- marks at downstream side of bridge, from rating curve extended above 150 cu ft/s (4.25 cu m/s) on basis of slope-area measurement of peak flow; minimum, 1.0 cu ft/s (0.028 cu m/s) May 29, 1973. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 800 cu ft/s (22.7 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Nov. 17 1700 838 23.7 5.67 1.728 May 18 1530 *1,550 43.9 7.28 2.219 Apr. 21 0545 1,030 29.2 6.15 1.874 May 21 1515 1,160 32.8 6.44 1.963 Minimum discharge, 3.4 cu ft/s (0.096 cu m/s) Mar 3-6. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 75 17 17 7.7 5.5 3.8 3.9 12 13 8.2 6.7 6.0 2 40 16 15 7.9 5.2 3.8 3.8 12 23 14 6.7 7.4 3 20 15 14 7.7 5.2 3.8 3.6 11 18 23 6.4 6.8 4 15 14 14 7.5 4.8 3.5 3.6 13 13 33 5.3 9.3 5 14 13 13 7.3 4.8 3.4 3.7 12 13 24 5.3 9.7 6 12 13 13 8.0 4.6 3.6 4.5 11 17 19 5.4 7.4 7 11 13 12 7.7 4.2 3.6 4.5 12 14 16 4.8 7.9 8 11 12 12 7.8 4.0 3.7 4.5 10 12 14 8.4 12 9 10 13 12 8.2 3.9 5.6 4.5 9.5 12 12 10 7.9 10 9.7 20 12 7.7 3.9 5.7 4.1 9.2 12 12 6.9 7.5 11 9.2 19 12 7.3 3.9 3.3 3.9 12 12 11 7.0 3.9 12 8.7 41 12 7.4 3.9 152 3.9 16 13 11 5.5 11 13 18 44 11 7.3 3.9 22 4.5 15 15 10 9.4 7.6 14 12 20 11 6.8 4.0 8.8 29 21 12 9.2 9.1 7.2 15 9.5 16 11 6.9 4.2 6.4 34 18 38 9.2 6.0 10 16 37 20 12 6.7 4.3 5.7 28 16 118 9.9 6.8 8.4 17 21 110 10 6.7 4.5 5.1 10 14 171 9.9 63 20 13 41 127 10 6.4 4.3 4.8 40 180 267 8.3 25 27 19 29 70 10 6.3 4.2 4.5 19 77 67 7.9 10 17 20 19 33 10 6.2 4.0 4.2 73 38 32 7.7 8.1 9.1 21 21 25 9.4 6.0 3.9 4.0 298 188 20 7.7 30 7.7 22 21 52 9.3 5.9 3.9 3.9 57 103 15 7.4 19 21 23 45 77 9.3 5.7 3.7 4.2 32 57 12 7.5 9.9 33 24 42 34 8.9 5.5 3.6 4.2 34 35 9.5 9.1 7.7 20 25 23 26 8.5 6.0 3.7 4.3 23 46 11 7.1 6.7 20 26 19 22 8.5 6.7 3.9 4.5 18 37 12 6.6 15 15 27 16 21 8.5 6.1 3.9 4.3 19 25 15 6.6 16 9.7 28 36 20 8.2 5.9 3.9 4.1 19 21 12 7.1 10 7.8 29 27 18 8.6 5.8 --- 3.9 15 15 9.1 7.4 8.3 7.0 30 23 21 11 6.0 3.9 13 15 8.5 7.7 6.7 6.2 31 19 --- 8.4 5.5 3.9 --- 14 --- 7.0 6.9 --- TOTAL 714.1 962 341.6 210.6 117.8 303.5 814.0 1074.7 1016.1 351.0 352.0 355.5 MEAN 23.0 32.1 11.0 6.79 4.21 9.79 27.1 34.7 33.9 11.3 11.4 11.9 MAX 75 127 17 8.2 5.5 152 298 188 267 33 63 33 MIN 8.7 12 8.2 5.5 3.6 3.4 3.6 9.2 8.5 6.6 4.8 6.0 CFSM 2.61 3.64 1.25 .77 .48 1.11 3.07 3.93 3.84 1.28 1.29 1.35 IN. 3.01 4.06 1.44 .89 .50 1.28 3.43 4.53 4.29 1.48 1.48 1.50 AC-FT 1420 1910 678 418 234 602 1610 2130 2020 696 698 705 CAL YR 1982 TOTAL 6738.7 MEAN 18.5 MAX 520 MIN 2.4 CFSM 2.10 IN 28.42 AC-FT 13370 WTR YR 1983 TOTAL 6612.9 MEAN 18.1 MAX 298 MIN 3.4 CFSM 2.05 IN 27.89 AC-FT 13120 156 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 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLT- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 01... 1410 JAN , 1983 25... 1340 MAR 16... 1210 MAY 06... 1210 AUG 16... 0925 16 282 3.3 26.0 1.5 7.8 99 23 K520 (560 5.6 309 8.4 25.0 <1.0 6.9 109 51 K13 130 5.7 276 1.2 25.0 <1.3 8.1 100 43 (150 510 Q.8 274 8.4 25.5 2.4 8.0 99 15 330 810 5.2 158 8.3 25.0 1.1 3.3 108 11 110 390 HARD- MAGNE- SODIUM POTAS- AL(A- CHLO- FLUO- HARD- NESS, CALCIUM srum, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- ors- 015- SORP- DIS- FIELD On- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1982 01... 130 JAN , 1983 25... 140 0 42 7.5 12 .5 1.0 140 8.0 8.7 .10 MAR 16... 120 MAY 06... 130 1 41 7.0 12 .5 1.3 130 8.1 8.7 .10 AUG 16... 140 4 45 7.4 11 .4 1.1 139 8.1 9.0 <.10 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER FENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 01... 2 <.010 1.0 <.010 .90 1.9 JAN , 1983 25... 22 185 2.3 1 .39 .010 .90 .030 <.10 MAR 16... <1 <.010 1.4 .030 <.10 MAY 06... 22 178 4.7 6 <.010 .60 <.010 <.10 AUG 16... 22 187 2.6 4 <.010 .70 <.010 .20 .90 CHRO- BARIUM. CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERA3LE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS 9) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV , 1982 01... 3.4 .070 JAN 1983 25... .160 2 100 3 <1 9 .1 <1 <1 MAR 16... .050 MAY 06... .040 AUG 16... 4.0 .070 2 100 1 1 2 <.1 <1 <1 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) OCT, 19 1330 23 213 24.0 JUN, 14 1235 10 267 27.0 DEC, 09 1345 12 260 23.0 JUL, 07 1040 14 275 26.0 FEB, 08 1410 4.0 295 25.5 SEP, 02 1000 6.3 286 30.0 APR, 13 1300 3.3 307 28.0 K = non-ideal count 157 RIO PORTUGUES BASIN 50116200 RIO PORTUGUES AT PONCE, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°00'20", long 66°36'28", 1,300 ft (400 m) south of Las Americas Avenue Bridge, 1.2 mi (1.9 km) south of CSG 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 1982 TO SEPTEMBER 1983 OXYGEN• OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM• TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL• FECAL, FLOM, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) CMG/L) ATION) (MG/L) 100 ML) 100 ML) NOV • 1982 02... 0850 14 415 8.1 25.0 7.0 8.9 108 11 51000 K11000 JAN • 1983 11... 1420 6.6 448 8.3 31.0 70 7.2 124 33000 3200 MAR 16... 1435 4.7 490 8.4 32.0 1.3 7.9 109 <10 2300 K170 MAY 19... 0805 107 249 7.8 22.5 55 3.9 103 11 29000 9500 JUN 07... 1340 14 403 8.6 33.0 11.8 165 AUG 16... 1220 5.4 458 8.0 33.0 43 6.0 33 45 52000 58000 HARD- NESS (MG/L AS DATE CAC03) HARD- NESS. NONCAR- 80NATE (MG/L CAC03) CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM, DIS- SOLVED (MG/L AS NA) SODIUM POTAS- ALKA- CHLO- FLUO- AD- SIUM, LINITY SULFATE RIDE, RIDE. SORP- DIS- FIELD DIS- DIS- DIS- TION SOLVED (MG/L SOLVED SOLVED SOLVED RATIO (MG/L AS (MG/L (MG/L (MG/L AS K) CAC03) AS SO4) AS CL) AS F) NOV . 1982 02... 150 JAN • 1983 11... 160 23 47 11 37 1.3 2.2 140 60 34 .30 MAR 16... 130 MAY 19... 100 10 30 6.1 13 .6 1.5 90 20 11 .20 JUN 07... 130 AUG 16... 160 77 44 11 35 1.3 2.6 78 53 31 .40 SOLIDS, SOLIDS, NITRO- SILICA, SUM Of SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN•AM- DIS- CONSTI- DIS- AT 105 GEN. GEN, GEN, GEN, GEN. MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE S/02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV • 1982 02... 18 .58 .020 .60 .090 .61 .70 1.3 JAN • 1983 11... 20 295 5.3 100 .35 .050 .40 .230 .07 .30 .70 MAR 16... <1 .87 .030 .90 .120 .08 .20 1.1 MAY 19... 20 156 45.2 46 2.2 .020 2.2 .060 .54 .60 2.8 JUN 07... AUG 16... 17 241 3.5 69 .19 .110 .30 .870 1.3 2.20 2.5 K = non-idleal count RIO PORTUGUES BASIN 50116200 RIO PORTUGUES AT PONCE, PR--Continued WATER-QUALITY DATA, WATER YEARS OCTOBER 1982 TO SEPTEMBER 1983 CHRO- NITRO- PHOS- BARIUM, TOTAL CADMIUM TOTAL MIUM, TOTAL LEAD, TOTAL MERCURY TOTAL SELE- SILVER, TOTAL GEN, TOTAL PHORUS, TOTAL ARSENIC TOTAL RECOV- ERABLE RECOV- ERABLE RECOV- ERABLE RECOV- ERABLE RECOV- ERABLE NIUM, TOTAL RECOV- ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) NOV , 1982 AS P) AS AS) AS BA) AS CD) AS CR) AS PS) AS HG) AS SE) AS AG) 02... 5.8 .090 JAN , 1983 11... 3.1 .430 2 100 2 6 7 .2 <1 1 MAR 16... 4.9 .100 MAY 19... 12 .100 JUN 07... AUG 16... 11 .360 2 200 1 2 3 <.1 <1 <1 CHLOR- DI- PCB, ALDRIN, DANE, DOD, DDE, DDT, AZINON, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN , 1983 07... 1340 <.10 <.01 <.10 <.01 <.01 <.01 .11 HEPTA- METH- DI- ENDO- HEPTA- CHLOR MALA- OXY- ELDRIN SULFAN, ENORIN, ETHION, CHLOR, EPDXIDE LINDANE THION, CHLOR, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1983 07... <.01 <.01 <.01 <.01 <.01 <.01 <.01 (.01 (.01 NAPH- THA-. METHYL METHYL LENES, PARA- TRI- PARA- POLY- PER- TOX- TOTAL THION, THION, MIREX, THION, CHLOR. THANE APHENE, TRI- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL THION DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1983 07... <.01 (.01 <.01 <.01 <.10 <.10 <1 <.01 158 159 RIO GUAYANILLA BASIN 50124200 RIO GUAYANILLA NEAR GUAYANILLA, P.R. LOCATION.--Lat 18°02'40", long 66°47'53", Hydrologic Unit 21010004, on left bank, 0.7 mi (1.1 km) north of junction of 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 sq mi (49.0 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1981 to current year. GAGE.--Water-stage recorder. Altitude of gage is 80 ft (24.4 m) from topographic map. REMARKS.--Records fair. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 14,700 cu ft/s (416 cu m/s) Sept. 12, 1982, gage height, 20.4 ft (6.21 m) from floodmarks, from rating curve extended above 100 cu ft/s (2.83 cu m/s) on basis of step-backwater analysis and indirect measurement of peak flow; minimum, 1.8 cu ft/s (0.051 cu m/s) Apr. 17-19, 1981. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 800 cu ft/s (22.7 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Apr. 21 0230 *2,010 56.9 11.55 3.520 Aug. 17 1645 970 27.5 9.69 2.954 Minimum discharge, 3.0 cu ft/s (0.085 cu m/s) Apr. 3-5, 9-13. DISCHARGE, IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 17 16 15 13 19 11 11 11 11 11 35 26 24 22 20 9.3 3.9 8.6 3.5 8.7 5.2 4.9 4.8 4.7 5.0 4.9 4.9 4.9 4.3 4.7 3.3 3.4 3.3 3.0 3.1 16 14 14 14 13 17 17 19 16 15 18 21 20 16 24 6.4 6.7 6.4 6.0 6.0 5.9 5.5 5.6 15 11 6 7 8 9 10 16 18 18 14 14 11 9.9 9.2 9.2 9.2 19 18 17 17 18 3.5 3.5 3.3 5.9 3.2 4.8 4.5 4.4 4.5 4.5 5.2 5.4 6.3 6.5 7.3 5.3 3.8 4.2 3.5 3.0 12 11 11 12 11 14 14 14 14 13 19 14 13 11 11 6.0 6.0 17 12 8.6 7.4 6.3 6.8 6.0 5.5 11 12 13 14 15 13 12 16 17 15 9.2 50 43 31 26 17 15 15 15 14 7.9 7.8 7.4 7.7 7.8 4.6 4.4 4.4 4.8 5.3 5.7 92 22 3.5 6.5 3.0 3.1 3.4 8.9 13 12 12 17 18 16 13 12 12 18 16 12 12 11 11 11 8.7 7.6 7.5 10 7.4 6.0 6.7 5.3 5.0 18 16 17 18 19 15 14 14 14 34 97 79 54 14 13 12 18 7.5 7.3 7.1 7.1 4.7 4.6 5.0 4.8 5.6 5.2 5.0 4.7 5.9 4.6 24 12 14 14 35 70 33 40 71 32 13 13 12 12 10 122 31 11 9.5 7.2 10 6.1 20 15 47 17 7.1 4.8 4.6 28 109 18 11 8.0 5.5 21 22 23 24 25 14 23 26 29 19 43 42 38 29 30 12 12 11 11 11 7.1 6.5 6.5 6.2 5.6 5.1 5.0 5.1 4.9 5.1 4.2 4.0 4.8 4.4 4.1 327 52 36 29 22 183 115 48 36 47 15 14 13 12 13 11 10 8.9 8.8 8.3 23 14 9.2 13 7.8 5.2 7.6 14 9.2 6.6 26 27 15 14 24 21 11 10 5.6 5.5 5.1 4.9 4.0 3.9 19 61 43 29 14 16 7.6 7.2 6.7 6.6 5.8 5.4 28 29 30 31 14 14 13 11 62 30 48 --- 9.8 10 12 9.9 5.4 5.2 5.2 5.3 5.0 --- 4.0 4.0 3.5 3.5 63 27 19 --- 24 21 19 13 17 17 19 --- 7.2 7.4 8.4 7.4 6.8 6.6 6.3 6.4 5.1 5.0 5.6 --- TOTAL MEAN MAX MIN CFSM IN. AC-FT 497 16.0 29 11 .85 .98 986 940.7 31.4 97 9.2 1.66 1.85 1870 485.7 15.7 35 9.8 .83 .96 963 225.2 7.26 9.3 5.2 .33 .44 447 134.9 4.82 5.3 4.4 .26 .27 268 259.1 8.36 92 3.5 .44 .51 514 796.8 26.6 327 3.0 1.41 1.57 1580 1028 33.2 183 11 1.76 2.02 2040 568 18.9 71 12 1.00 1.12 1130 377.2 12.2 24 7.2 .65 .74 748 410.7 13.2 122 6.0 .70 .81 815 223.8 7.46 18 5.0 .40 .44 444 CAL YR 1982 TOTAL 5792.0 MEAN 15.9 MAX 500 MIN 3.7 CFSM .84 IN 11.40 AC-FT 1149J WTR YR 1983 TOTAL 5947.1 MEAN 16.3 MAX 327 MIN 3.0 CFSM .86 IN 11.70 AC-FT 11800 WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 DATE TIME STREAMFLOW, INSTANTANEOUS SPECIFIC CON- DUCTANCE TEMPERA­ TURE DATE TIME STREAMFLOW. INSTANTANEOUS SPECIFIC CON­ DUCT ANCE TEMPERA­ TURE (CFS) CUMHOS) (DEG C) (CFS) (UMHOS) CDEG C) OCT, 13 1020 NOV, 12 1150 DEC. 09 1010 JAN. 17 1255 FEB. 02 1050 MAR, 16 1155 14 16 13 7.4 5.1 6.1 413 363 313 390 370 425 28.0 26.0 22.0 27.0 25.0 28.0 APR, 12 1300 MAY, 09 1030 JUN, 14 1250 JUL, 06 0950 AUG, 03 1500 SEP, 15 1028 3.0 12 13 17 6.2 5.1 387 446 -- 370 315 392 28.0 23.0 30.5 27.0 33.0 29.0 160 RIO GUAYANILLA BASIN 50124700 RIO GUAYANILLA AT CENTRAL RUFINA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°00'40", long 66°46'49", at dirt road bridge, 0.7 mi (1.1 km) from mouth, 0.9 mi (1.4 km) east of Central Rufina and 0.9 mi (1.4 km) southeast of Guayanilla. DRAINAGE AREA.--22.8 sq mi (59.1 sq km). PERIOD OF RECORD.--Water years 1960-65, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COL/- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW. CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MGR) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 03... 0855 6.2 535 7.6 26.0 2.1 4.8 60 14 510000 93000 JAN , 12... 1983 0940 3.0 685 7.3 25.0 2.0 1.0 12 2500000 70000 MAR 31... 1100 1.2 960 7.6 27.0 6.5 1.6 20 66 2000000 190000 MAY 19... 1145 29 390 7.9 27.5 14 7.7 98 <10 K700000 98000 JUN 07... 1540 7.2 558 7.8 31.0 5.8 78 AUG 17... 0825 2.1 638 7.7 27.0 1.4 .8 10 53 K1900000 800000 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS NESS, NONCAR- CALCIUM DIS- SLUM, DIS- SODIUM, DIS- AD- SORP- SIUM, DIS- LINITY FIELD SULFATE DIS- RIDE. DIS- RIDE, DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/I (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1982 03... 190 JAN , 1983 12... 240 11 65 19 37 1.1 3.9 230 73 37 .10 MAR 31... 350 MAY 19... 160 14 44 13 17 .6 1.9 150 36 17 .20 JUN 07... 190 AUG 17... 250 3 69 18 41 1.2 4.0 244 66 41 .10 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN. GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN. (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 03... 6 .31 .090 .40 3.20 .30 3.50 3.9 JAN , 1983 12... 21 394 3.2 26 .06 .040 .10 6.30 8.7 15.0 15 MAR 31... <1 .03 .070 .10 14.0 15 29.0 29 MAY 19... 18 237 18.6 14 .38 .020 .40 1.30 .80 2.10 2.5 JUN 07... AUG 17... 21 406 2.3 8 .06 .040 .10 6.50 6.5 13.0 13 K = non-ideal count RIO GUAYANILLA BASIN 50124700 RIO GUAYANILLA AT CENTRAL RUFINA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHRO- BARIUM, CADMIUM MIUM. LEAD. MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV r 1982 03... 17 .770 JAN r 1983 12... 67 1.80 3 100 1 8 2 .1 <1 <1 MAR 31... 130 3.50 MAY 19... 11 .210 JUN 07... AUG 17... 58 1.50 2 200 1 9 5 .1 <1 <1 CHLOR- DI- PCB, ALORIN. DANE, ODD. DOE, DDT, AZINON, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN , 1983 07... 1540 <.10 <.01 <.10 <.01 <.01 <.01 .04 HEPTA- METH- DI- ENDO- HEPTA- CHLOR MALA- OXY- ELDRIN SULFAN. ENGRIN, ETHION, CHLOR. EPDXIDE LINDANE THION, CHLOR, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN 1983 07... <.01 <.01 <.01 <.01 <.01 <.01 <.01 .04 <.01 NAPH- THA- METHYL METHYL LINES. PARA- TRI- PARA- POLY- PER- TOX- TOTAL THION, THION, MIREX. THION, CHLOR. THANE APHENE. TRI- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL THION DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN r, 1983 07... <.01 <.01 <.01 <.01 <.10 <.10 <1 <.01 161 162 RIO YAUCO BASIN 50126150 RIO YAUCO ABOVE DIVERSION MONSERRATE NEAR YAUCO, PR LOCATION.--Lat 18°02'58", long 66°50'30", Hydrologic Unit 21010004, on right bank off Highway 375, about 300 ft (91 m) upstream from diversion Monserrate, 0.1 mi (0.2 km) downstream from Quebrada de las Quebradas, 0.9 mi (1.4 km) downstream from Rio Duey, and 1.0 mi (1.6 km) northeast of Yauco Plaza. DRAINAGE AREA.--27.2 sq mi (70.4 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--November 1976 to current year. GAGE.--Water-stage recorder. Altitude of gage is 115 ft (35 m), from topographic map. REMARKS.--Records poor. AVERAGE DISCHARGE.--6 years (1978-83), 22.7 cu ft/s (0.643 cu m/s), 11.33 in /yr (288 mm/yr), 16,450 acre-ft/yr (20.3 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 10,500 cu ft/s (297 cu m/s) Aug. 31, 1979, gage height, 9.83 ft (2.996 m) from flood- mark, from rating curve extended above 300 cu ft/s (8.50 cu m/s) on basis of step-backwater analysis; minimum daily discharge, 0.2 cu ft/s (0.006 cu m/s) June 30, 1978. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 1,000 cu ft/s (28.3 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Oct. 1 1630 1,010 28.6 4.11 1.253 Apr. 21 0230 *5,930 168 7.95 2.423 Minimum daily discharge, 1.5 cu ft/s (0.042 cu m/s) Feb. 8-10, 13, 14, 16, 17, 19, 20. DISCHARGE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 174 3.3 135 6.6 1.6 1.3 3.4 10 11 15 3.5 5.4 2 152 8.0 70 7.3 1.6 1.3 3.8 9.1 1C 18 3.4 5.2 3 40 8.3 40 5.4 1.6 1.8 2.8 10 11 17 3.3 5.0 4 46 3.0 32 5.9 1.6 1.7 2.7 8.1 9.0 15 3.4 11 5 24 8.0 28 5.5 1.8 1.7 3.3 7.2 8.5 20 3.5 3.0 6 13 7.5 17 5.2 1.7 1.3 4.5 7.0 8.5 10 3.4 6.0 7 11 7.5 12 5.0 1.6 1.3 5.6 7.0 8.5 8.0 3.3 5.5 3 14 7.5 9.0 5.0 1.5 1.9 6.6 7.0 8.0 7.5 10 5.0 9 9.2 7.0 9.7 4.7 1.5 2.5 4.3 12 8.0 7.5 6.0 4.8 10 7.5 6.8 9.6 4.5 1.5 4.0 2.9 24 7.8 7.0 4.0 4.5 11 7.5 9.3 9.7 4.2 1.6 3.0 2.7 10 7.6 7.5 4.0 4.0 12 6.8 47 10 4.0 1.6 100 2.7 17 7.6 7.5 3.5 5.3 13 7.0 51 9.0 3.7 1.5 20 3.1 36 7.5 7.0 3.5 4.4 14 8.0 32 9.4 3.5 1.5 3.0 12 32 10 7.0 5.0 4.1 15 7.0 24 9.3 3.4 1.7 5.0 26 30 9.0 7.0 3.3 11 16 7.0 23 12 3.4 1.5 3.5 8.1 14 35 7.5 5.0 9.3 17 6.5 81 10 3.2 1.5 3.1 6.0 10 45 7.0 143 6.3 18 6.5 49 9.5 3.0 1.6 3.1 40 63 79 6.5 40 8.4 19 6.5 59 14 2.3 1.5 3.0 15 127 33 6.0 10 6.0 20 7.0 38 19 2.7 1.5 3.0 23 180 2C 6.0 7.0 5.5 21 6.5 55 12 2.5 1.6 2.9 735 232 16 5.5 20 5.2 22 19 30 10 2.3 1.6 2.6 86 190 14 5.5 11 10 23 23 25 9.0 2.2 1.6 2.7 28 47 12 5.0 8.0 37 24 25 30 8.5 2.1 1.6 2.3 15 20 11 5.0 10 19 25 15 22 8.0 2.0 1.6 4.5 10 61 12 5.0 7.0 10 26 12 18 7.5 2.0 1.7 5.2 8.7 75 13 4.5 6.0 6.6 27 11 16 7.2 1.9 1.7 4.4 121 23 13 4.0 5.8 6.4 28 10 53 6.8 1.3 1.7 3.9 140 17 14 4.0 5.6 5.2 29 10 15 6.7 1.3 --- 3.5 43 15 14 3.8 5.6 5.3 30 9.5 87 28 1.7 2.3 14 13 16 4.0 5.6 5.9 31 8.0 --- 7.6 1.7 3.1 --- 12 --- 3.7 5.5 --- TOTAL 709.5 845.6 535.5 111.1 44.6 210.9 1379.2 1330.4 479.0 244.0 358.2 235.3 MEAN 22.9 28.2 18.9 3.58 1.59 6.80 46.0 42.9 16.0 7.87 11.6 7.84 MAX 174 87 135 7.3 1.8 100 735 232 79 20 143 37 MIN 6.5 6.3 6.7 1.7 1.5 1.7 2.7 7.0 7.5 3.7 3.3 4.0 CFSM .84 1.04 .70 .13 .06 .25 1.69 1.58 .59 .29 .43 .29 IN. .97 1.16 .80 .15 .06 .29 1.89 1.82 .66 .33 .49 .32 AC-FT 1410 1680 1160 220 38 413 2740 2640 950 484 710 467 CAL YR 1982 TOTAL 6115.6 MEAN 16.8 MAX 784 MIN 1.8 CFSM .62 IN 8.36 AC-FT 12130 WTR YR 1983 TOTAL 6533.3 MEAN 17.9 MAX 735 MIN 1.5 CFSM .66 IN 8.93 AC-FT 12960 WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE GATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) OCT, 12 1100 6.3 414 23.0 APR. 11 1145 2.9 519 28.0 NOV, 10 1250 6.3 385 29.0 MAY. 05 1110 7.2 423 28.0 DEC. 10 1045 9.7 321 24.0 SEP. 15 1238 4.3 400 29.0 MAR. 14 1030 6.3 392 26.0 163 RIO YAUCO BASIN 50128000 RIO YAUCO NEAR YAUCO, PR LOCATION.--Lat 17°59'19", long 66°49'55", Hydrologic Unit 21010004, on right bank at downstream side of bridge on Highway 335, 0.8 mi (1.3 km) northwest of Central San Francisco and 3.4 mi (5.5 km) southeast of junction of Highways 335 and 2 in Yauco. DRAINAGE AREA.--45.5 sq mi (117.8 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1960 (discharge measurements only), May 1961 to December 1964, November 1976 to current year. GAGE.--Water-stage recorder. Datum of gage is 15.14 ft (4.615 m) above mean sea level, datum of 1929. Prior to Oct. 1, 1978, at same site at datum 4.0 ft (1.219 m) higher. REMARKS.--Records poor. Natural flow of stream is affected by transbasin diversions, storage reservoirs, power development, diversions for irrigation and municipal use, and return flow from irrigated areas. AVERAGE DISCHARGE.--6 years (1978-83), 18.5 cu ft/s (0.524 cu m/s), 5.52 in/yr (140 mm/yr), 13,400 acre-ft/yr (16.5 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 10,300 cu ft/s (292 cu m/s) Sept. 13, 1982, gage height, 15.0 ft (4.57 m), from floodmarks, from rating curve extended above 2,000 cu ft/s (56.6 cu m/s) on basis of step-backwater analysis and indirect measurement of peak flow; no flow many days in most years. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 1,000 cu ft/s (28.3 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Oct. 1 2015 1,320 37.4 10.93 3.331 Aug. 17 1900 1,550 43.9 11.42 3.481 Apr. 21 0730 *4,430 125 14.02 4.273 Minimum discharge, 0.50 cu ft/s (0.014 cu m/s) Apr. 11, 13. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 231 47 120 2.8 1.5 1.5 1.1 9.2 7.3 2.2 1.0 1.4 2 118 22 32 2.8 1.4 1.5 .88 7.9 6.8 2.2 .99 2.0 3 14 116 20 2.8 1.4 1.4 .94 7.5 6.5 2.1 1.0 1.6 4 8.1 36 15 2.8 1.4 1.4 .79 6.7 6.3 2.0 .95 1.5 5 14 6.3 15 2.7 1.4 1.4 .81 5.7 5.8 9.3 1.0 1.4 6 6.3 4.3 10 2.8 1.4 1.3 .32 5.6 4.2 5.3 1.0 1.3 7 5.6 3.4 8.4 2.7 1.5 1.3 .76 5.5 4.8 2.7 .95 1.3 8 5.9 3.2 7.1 2.7 1.4 1.3 .76 4.9 4.4 2.1 .94 1.2 9 5.2 3.2 5.3 2.6 1.5 1.4 .64 4.7 4.0 1.8 .98 1.3 10 4.8 3.0 4.9 2.6 1.4 1.4 .59 4.4 3.9 1.6 1.0 1.2 11 4.5 3.4 4.6 2.4 1.4 1.4 .53 4.4 3.9 1.6 .98 1.2 12 4.5 31 4.3 2.4 1.4 154 .53 4.2 3.5 1.5 .98 1.3 13 7.4 76 4.1 2.3 1.4 34 .54 5.2 3.4 1.4 .94 1.2 14 11 13 4.0 2.2 1.4 3.9 .59 10 3.5 1.3 .87 1.2 15 6.8 21 3.9 2.2 1.5 2.7 .57 9.3 4.6 1.3 .81 1.2 16 4.8 7.5 3.6 2.2 1.5 2.4 .66 6.7 4.5 1.3 .81 1.2 17 3.8 267 3.5 2.2 1.7 2.1 .67 5.8 9.0 1.3 223 1.2 18 4.9 127 3.5 2.0 1.6 1.9 3.1 45 21 1.2 73 1.2 19 18 247 6.5 2.0 1.5 1.8 4.6 109 13 1.2 4.4 1.2 20 11 183 11 1.9 1.5 1.7 2.1 157 6.7 1.2 2.5 1.2 21 6.7 263 5.3 1.9 1.5 1.6 1430 172 3.4 1.2 20 1.2 22 6.6 174 4.2 1.8 1.5 1.5 165 210 3.4 1.3 '9.5 1.2 23 6.6 73 3.9 1.8 1.5 1.5 65 41 3.2 1.3 2.7 12 24 11 66 3.9 1.7 1.5 1.5 33 22 3.0 1.3 1.9 6.8 25 6.3 17 3.4 1.7 1.6 1.4 20 26 2.7 1.1 2.0 2.3 26 4.5 12 3.5 1.7 1.6 1.3 15 56 2.6 1.2 1.7 1.6 27 5.3 20 3.3 1.6 1.4 1.2 88 21 2.5 1.2 1.7 1.6 28 3.5 73 3.2 1.6 1.4 1.1 112 15 2.5 1.2 1.6 1.6 29 3.3 36, 2.9 1.6 --- 1.1 43 11 2.4 1.2 1.6 1.6 30 3.3 61 3.3 1.6 1.1 13 9.3 2.4 1.2 1.5 1.7 31 75 --- 3.2 1.5 1.1 --- 8.5 --- 1.0 1.5 --- TOTAL 621.7 2015.3 326.8 67.6 41.2 234.2 2005.98 1010.5 155.2 57.8 363.80 57.9 MEAN 20.1 67.2 10.5 2.18 1.47 7.55 66.9 32.6 5.17 1.86 11.7 1.93 MAX 231 267 120 2.8 1.7 154 1430 210 21 9.3 223 12 MIN 3.3 3.0 2.9 1.5 1.4 1.1 .53 4.2 2.4 1.0 .81 1.2 CFSM .44 1.48 .23 .05 .03 .17 1.47 .72 .11 .04 .26 .04 IN. .51 1.65 .27 .06 .03 .19 1.64 .83 .13 .05 .30 .05 AC-FT 1230 4000 648 134 82 465 3980 2000 308 115 722 115 CAL YR 1982 TOTAL 5051.77 MEAN 13.8 MAX 1000 MIN .06 CFSM .30 IN 4.13 AC-FT 10020 WTR YR 1983 TOTAL 6957.98 MEAN 19.1 MAX 1430 MIN .53 CFSM .42 IN 5.69 AC-FT 13800 WATER-QUALITY RECORDS PERIOD OF RECORD.-- WATER YEAR AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 STREAMFLOW. SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS OUCTANCE TURE DATE TIME INSTANTANEOUS OUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) OCT, 12 1330 4.4 964 23.0 APR. 11 1500 .53 1040 28.0 NOV, 09 1230 3.2 950 27.0 MAY. 05 1325 5.4 950 27.5 DEC. 10 1255 4.7 660 25.0 SEP. 14 1350 1.2 957 29.0 MAR. 14 1300 3.5 490 26.0 164 CANAL PRINCIPAL DE RIEGO VALLE DE LAJAS BASIN 50128950 LAJAS IRRIGATION CANAL NEAR BOQUERON, PR LOCATION.--Lat 18°02'14", long 67°08'22", Hydrologic Unit 21010004, on downstream side of wooden foot bridge near dirt levee road, 0.5 mi (0.8 km) north of intersection of Highways 101 and 103, 1.8 mi (2.9 km) northeast of Boquer6n. DRAINAGE AREA.--Indeterminate. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--August 1980 to current year. GAGE.--Water-stage recorder. Altitude of gage is shout 82 ft (25 m), from topographic map. REMARKS.--Records poor. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum discharge, 34 cu ft/s (0.963 cu m/s) June 11, 1981, gage height, 2.56 ft (0.780 m) from rating curve extended above 10 cu ft/s (0.283 cu m/s) on basis of step-backwater analysis; no flow many days each year. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum discharge, 23 cu ft/s (0.651 cu m/s) Apr. 21, gage height 1.80 ft (0.549 m); no flow many days. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR ASR MAY JUN JUL AUG SEP 1 .00 2.6 .00 .00 1.0 2.7 .06 .00 .00 2.4 2.1 2 .61 .27 .00 .00 1.4 .00 .30 .10 .00 .04 t 4.9 3 .13 2.4 .00 .00 .78 .24 .04 .82 .00 .02 A .02 4 .06 3.3 .00 .00 .80 1.2 .02 .74 .00 .06 .04 .02 5 .02 .01 .00 .13 .00 .00 .00 .39 .00 2.0 2.8 .58 6 .00 .00 .00 .11 .00 .02 1.7 .74 .00 2.3 .00 3.6 7 .00 .02 .00 .34 .00 2.0 .22 .02 2.5 3.3 .00 6.1 8 .00 .38 .00 .00 2.3 5.7 1.8 .00 .39 A .73 .45 9 .00 .88 .00 .00 .23 3.7 .00 .00 .02 4.6 .01 10 .00 .10 .00 1.3 .90 1.8 .00 .00 .00 3.2 .00 11 .07 3.4 .00 .00 .98 2.3 .00 .45 .00 4.1 .00 12 2.6 6.4 .00 .19 .00 2.9 1.4 1.2 .00 3.7 1.3 13 4.7 .50 .00 1.8 .00 .77 3.5 1.5 .00 .16 1.9 14 1.3 .21 1.0 4.3 1.2 1.4 1.6 5.7 .00 .01 1.8 15 1.2 3.2 1.8 .00 7.9 1.2 1.1 .22 .10 3.0 4.3 16 .00 2.0 1.4 .00 2.6 .02 .00 .22 2.0 6.0 6.6 17 .00 5.3 1.6 .12 .00 .02 .00 .00 2.9 2.1 .22 18 .94 .07 .43 1.6 .00 .00 1.6 4.9 1.4 4.4 .01 19 2.5 .00 1.3 1.0 .00 .00 .59 .40 1.1 .22 4.5 20 5.1 .50 .94 .00 .00 .00 2.0 .CO .52 .06 5.2 21 1.8 .20 .45 .33 .00 .00 11 1.1 2.1 5.0 5.4 22 .15 .00 .00 .00 .16 .00 .02 .37 2.6 .06 4.1 23 .45 .00 .14 .00 4.1 .00 .00 .00 1.8 3.0 1.9 24 .19 .00 .21 .56 1.3 .00 .00 .00 .02 6.7 .52 25 1.3 .01 .00 3.5 .00 .14 .00 .00 .00 1.6 .06 26 1.8 .01 .00 1.7 .00 .04 .00 .01 .00 1.8 5.2 27 1.1 .00 .00 1.1 .85 .00 .00 .00 .00 .30 7.1 28 1.2 .04 .14 3.6 3.1 .00 1.4 .00 1.2 .10 1.6 29 .38 .01 .09 .28 .16 1.9 .00 .39 1.6 1.4 30 .16 .00 .00 .34 .54 .04 .00 1.6 1.2 6.3 31 1.6 --- .00 1.4 .58 --- .00 --- 1.1 TOTAL 29.36 31.81 10.05 23.70 29.50 27.43 30.29 18.88 20.54 77.19 MEAN .95 1.06 .32 .76 1.05 .83 1.01 .61 .68 2.57 MAX 5.1 6.4 1.8 4.3 7.9 5.7 11 5.7 2.8 7.1 MIN .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 AC-FT 58 63 20 47 59 54 60 37 41 153 A No gage-height record. WATER-QUALITY RECORDS PERIOD OF RECORD.--JANUARY TO SEPTEMBER 1983 WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMMOS) (DEG C) (CFS) (UMMOS) (DEG C) JAN• 13 0345 2.2 306 24.0 MAY, 13 0320 1.7 288 27.0 APR, 15 0910 1.3 287 25.5 SEP, 07 1630 4.6 249 31.0 165 RIO LOCO BASIN 50129300 LAJAS DRAINAGE CANAL NEAR ENSENADA, PR LOCATION.--Lat 18°00'40", long 66°58'24", Hydrologic Unit 21010004, on upstream side of Cuesta Blanca Bridge on dirt road, 1.1 mi (1.8 km) north of Highway 116, 1.0 mi (1.6 km) below Quebrada Jicara, 3.9 mi (6.3 km) above Rio Loco, and 4.0 mi (6.4 km) northwest of Ensenada. DRAINAGE AREA.--Indeterminate. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1979 to current year. GAGE.--Water-stage recorder. Altitude of gage is about 15.1 ft (4.602 m), from Hydrologic Atlas of Lajas Valley. REMARKS.--Records poor. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum discharge, 1,720 cu ft/s (48.7 cu m/s) Sept. 1, 1979, gage height, 16.44 ft (5.011 m), from rating curve extended above 600 cu ft/s (17 cu m/s); minimum daily, 1.0 cu ft/s (0.028 cu m/s) July 16, 1979, May 9, 16, 1982. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum discharge, 448 cu ft/s (12.7 cu m/s) Apr. 21,gage height, 9.05 ft (2.758 m); minimum daily, 1.2 cu ft/s (0.034 cu m/s) Dec. 18. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 3.0 9.3 A 3.1 A 2.6 2.5 3.5 4.6 3.3 B 2 3.9 9.7 2.9 3.1 2.4 4.0 6.8 3.2 3 3.3 13 2.5 3.4 2.1 3.6 2.7 2.6 4 2.9 8.8 2.0 3.6 2.1 2.9 2.5 2.2 5 3.3 11 2.0 3.7 2.3 3.1 2.2 2.6 6 3.6 4.1 1.8 2.4 2.5 2.9 4.5 4.6 7 3.8 2.4 2.2 3.0 2.6 2.9 3.6 5.3 8 3.1 3.4 2.1 2.9 3.2 2.7 3.0 6.9 9 3.0 A 2.5 A 3.4 3.2 2.9 8.4 3.1 10 2.9 2.8 3.6 4.1 2.5 3.0 4.4 2.5 11 2.8 2.4 3.9 4.0 2.4 3.1 7.1 2.9 12 3.3 2.7 3.2 36 2.7 8.6 5.3 13 2.4 A A 2.1 87 2.8 17 13 14 5.0 1.6 1.9 14 3.1 244 16 15 17 1.3 2.7 5.6 3.8 77 43 16 8.4 1.5 2.8 4.3 4.8 25 48 17 4.6 1.5 3.4 3.6 4.2 20 40 18 4.2 1.2 3.3 2.7 4.6 77 6.4 19 38 15 3.6 2.2 4.8 226 3.3 20 35 112 2.9 2.1 5.3 57 9.5 21 103 31 2.3 5.6 301 98 4.5 22 21 9.2 2.4 3.8 127 136 2.0 23 43 8.3 2.9 5.4 19 48 1.9 24 46 25 3.4 4.2 7.3 38 1.8 25 41 6.2 4.4 3.0 4.9 36 2.6 26 16 4.3 4.5 2.3 4.2 42 5.1 27 2.9 3.5 3.4 2.0 3.7 42 4.3 28 2.9 3.0 2.7 2.3 5.9 59 6.5 29 3.6 3.2 --- 2.5 9.4 19 6.4 30 3.6 3.2 2.5 4.4 3.6 4.0 31 5.2 A 3.3 A 2.7 --- 3.6 --- B TOTAL 441.7 230.0 550.7 1311.4 273.4 MEAN 14.2 7.42 18.4 42.3 9.11 MAX 103 87 301 244 48 MIN 2.4 2.0 2.1 2.7 1.8 AC-FT 876 456 1090 2600 542 A No gage-height record. B Discharge not determined but less than 50 cu ft/s. WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMNOS) (DEG C) (CFS) (UMMOS) (DEG C) OCT, 07 1300 5.0 927 30.0 APR, 15 1120 3.8 1190 27.5 NOV, 08 1105 2.2 783 30.5 MAY, 13 1057 5.7 1110 30.5 MAR, 18 1010 3.0 949 28.0 166 RIO LOCO BASIN 50129700 RIO LOCO AT GUANICA, PR WATER-QUALITY RECORDS LOCATION.--Lat 17 °58'33", long 66°54'52", 0.6 mi (1.0 km) northwest of Guanica and 1.2 mi (1.9 km) northeast of Ensenada. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1975 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL. FECAL. FLOM, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 03... 1140 11.0 36600 7.9 26.0 4.4 7.6 108 23 4200 8300 JAN . 1983 12... 1200 11.0 36300 7.9 28.0 3.5 6.0 87 K47 460 MAR 31... 0835 1.00 28400 7.6 29.5 2.2 3.4 49 600 K33 280 MAY 18... 1400 E15 662 7.5 27.0 5.0 4.8 60 12 6000 2200 JUN 09... 0815 E.00 13800 7.7 28.0 5.4 72 AUG 17... 1020 1.00 12100 7.6 27.0 2.0 .6 8 240 2000 K1800 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUMe SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE. NESS NONCAR- DIS- DIS- DIS- SORP- On- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CACC3) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV , 1982 03... 130 JAN , 1983 12... 4900 4660 130 1100 8400 53 290 200 2300 15000 .60 MAR 31... 260 11000 MAY 18... 220 16 37 30 51 1.5 3.2 200 41 57 .20 JUN 09... 300 AUG 17... 1500 1270 120 300 2100 24 78 262 590 3900 .40 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GENeAM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + SOLVED TUENTS, SOLVED DEG. C. NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) NITRO- GEN. TOTAL (MG/L AS N) NOV . 1982 03... 12 .39 .010 .40 .050 .45 .50 .90 JAN , 1983 12... 7.1 27300 73.7 66 <.010 <.10 .150 .15 .30 MAR 31... 22 .020 <.10 .120 <.10 MAY 18... 26 365 6 .28 .020 .30 .060 .64 .70 1.0 JUN 09... AUG 17... 27 7270 8 <.010 <.10 .040 .56 .60 E = estimate K = non-ideal count RIO LOCO BASIN 50129700 RIO LOCO AT GUANICA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHRO- BARIUM. CADMIUM MIUM. LEAD, MERCURY SILVER. NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS P8) AS MG) AS SE) AS AG) NOV r 1982 03... 4.0 .110 JAN r 1983 12... .130 1 100 2 20 3 <.1 <1 <1 MAR 31... .130 MAY 18... 4.4 .520 JUN 09... AUG 17... .220 2 100 1 7 3 .3 <1 <1 CHLOR- DI- PCB, ALORIN, DANE, Me DDEt DDT. AZINON, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN , 1983 09... 0815 <.10 <.01 <.10 <.01 <.01 <.01 <.01 HEPTA- METH- DI- ENDO- HEPTA- CHLOR MALA- OXY- ELDRIN SULFAN, ENCRIN, ETHION. MORA, EPDXIDE LINDANE THION, CHLOR, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN r 1983 09... <.01 <.01 <.01 <.01 <.01 <.01 <.01 <.01 <.01 NAPH- THA- METHYL METHYL LINES, PARA- TRI- PARA- POLY- PER- TOX- TOTAL THIONr THIONr MIREXr THION, CHLOR. THANE APHENE, TRI- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL THION DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN , 1983 09... <.01 <.01 <.01 <.01 <.10 <.10 <1 <.01 167 Rio Grande de Anosco basin MARICAO Rosario Drainage boundary 1380 HORMIGU E r O.°" 11 Laguna Joy Rio .AOUADILLA najibo 1336 QED WC:OE PONCE. OUAYAMA. ABO ROJO 32010 Map area SAN GERMAN —onaii 0 • GRAND SNBA14A Rlo Loco basin LAJ EXPLANATION A1380 SURFACE-WATER STATION AND NUMBER 2,1300 LOW-FLOW STATION AND NUMBER v1297 QUALITY-OF-WATER STATION AND NUMBER 0143 WELL AN WELL NUMBER GUANICA ENSENADA M A R CARIBE Figure 23.--Rio Guanajibo basin. 170 RIO GUANAJIBO BASIN 50133600 RIO GUANAJIBO NEAR SAN GERMAN, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°07'18", long 67°03'56", at bridge on Highway 347, 2.2 mi (3.5 km) northwest of San German plaza. DRAINAGE AREA.--45.5 sq mi (117.8 sq km). PERIOD OF RECORD.--November 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLT- STREP* SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOM, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 04... 1330 32 419 7.9 27.0 19 6.5 83 14 50000 5600 JAN , 1983 13... 0905 18 582 7.8 24.0 1.4 3.4 41 K68000 48000 MAR 30... 1215 7.4 636 7.8 26.0 1.0 .0 0 49 K1800000 50000 MAY 04... 1345 21 543 7.6 27.0 6.2 5.8 73 24 57000 2000 AUG 18... 0930 40 440 7.9 27.0 3.5 3.2 40 28 K93000 22000 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS 504) AS CL) AS F) NOV , 1932 04... 180 JAN , 1983 13... 260 11 27 47 23 .6 2.4 250 31 30 .40 MAR 30... 290 MAY 04... 260 20 28 46 22 .6 2.0 240 26 23 .30 AUG 18... 210 0 23 36 14 .4 1.8 230 19 18 .20 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO." SOLVED TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L On- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 04... 47 .47 .030 .50 .230 .57 .80 1.3 JAN , 1983 13... 35 346 16.8 5 .16 .040 .20 1.20 .70 1.90 2.1 MAR 30... 3 .020 <.10 2.90 1.8 4.70 MAY 04... 34 325 18.4 6 .13 .070 .20 .940 .16 1.10 1.3 AUG 18... 32 282 30.4 2 .17 .030 .20 .500 .80 1.30 1.5 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUMr RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS 8A) AS CD) AS CR) AS P3) AS HG) AS SE) AS AG) NOV , 1982 04... 5.8 .230 JAN , 1983 13... 9.3 .900 2 <100 2 5 2 <.1 <1 1 MAR 30... 1.50 MAY 04... 5.8 .420 AUG 18... 6.6 .310 2 200 <1 5 5 <.1 <1 <1 K = non-ideal count RIO GUANAJIBO BASIN 171 50136000 RIO ROSARIO AT ROSARIO, PR LOCATION.--Lat 18°10'22", long 67°04'31", Hydrologic Unit 21010003, on left bank above low dam, 0.2 mi (0.3 km) below Quebrada Figueroa, 0.7 mi (1.1 km) northeast of Rosario, and 1.6 mi (8.6 km) below Quebrada Palma. DRAINAGE AREA.--16.4 sq mi (42.5 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1960 to June 1966 (gage-height records only) in files of Puerto Rico Water Resources Authority. June 1975 to current year. GAGE.--Water-stage recorder and concrete control. Altitude of gage is 230 ft (70 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--8 years (1976-83), 44.4 cu ft/s (1.257 cu m/s), 36.77 in/yr (934 mm/yr), 32,170 acre-ft/yr (39.7 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 33,800 cu ft/s (957 cu m/s) Sept. 16, 1975, gage height, 19.6 ft (5.97 m), from flood- marks, from rating curve extended above 60 cu ft/s (1.70 cu m/s) on basis of slope-area measurement of peak flow; minimum daily discharge, 2.4 cu ft/s (0.068 cu m/s) June 18, 21, 1977. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 1,500 cu ft/s (42.5 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Oct. 18 2115 2,340 66.3 6.60 2.012 May 7 1730 1,860 52.7 6.05 1.844 Nov. 16 1815 2,550 72.2 6.82 2.079 May 18 1515 *4,190 119 8.23 2.508 Minimum discharge, 7.8 cu ft/s (0.221 cu m/s) Apr. 4. DISCHARGE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 52 66 80 30 16 11 8.4 14 34 29 21 27 2 47 73 65 27 15 11 8.4 12 59 25 22 25 3 42 47 60 25 15 11 8.4 10 125 25 19 25 4 40 40 56 25 15 11 8.1 70 78 71 69 24 5 37 43 54 25 17 11 8.6 48 51 49 31 24 6 42 40 50 25 16 11 8.8 13 42 27 21 23 7 39 35 48 24 15 11 12 176 74 23 19 23 3 70 33 46 23 15 13 16 67 49 22 30 23 9 43 33 44 23 15 11 9.3 28 38 28 26 22 10 35 38 42 23 15 10 8.7 27 34 26 22 209 11 32 45 40 22 14 10 8.6 27 31 42 22 133 12 31 81 38 22 14 16 8.7 24 29 23 22 64 13 34 82 37 21 14 15 8.5 79 28 21 36 41 14 55 49 35 22 13 13 8.4 104 26 18 39 31 15 44 53 34 24 13 11 8.4 54 25 17 39 29 16 35 251 33 21 13 10 9.3 30 25 26 36 38 17 32 231 32 21 13 9.7 9.3 32 26 42 34 135 18 202 229 31 20 13 9.7 9.8 433 28 60 38 82 19 193 184 31 20 13 9.4 8.5 231 24 37 32 48 20 117 105 30 21 14 9.6 28 162 23 25 61 36 21 73 87 29 20 15 9.5 151 236 23 21 84 33 22 57 72 28 19 13 9.3 19 230 22 19 60 43 23 48 63 27 10 13 9.2 12 175 21 18 45 70 24 44 123 27 18 13 9.2 11 150 21 19 38 47 25 40 96 27 13 12 3.9 9.3 104 20 16 146 36 26 57 67 27 17 12 9.0 8.6 81 21 16 138 31 27 50 61 25 17 12 9.0 8.6 61 21 16 77 29 28 43 60 25 17 11 9.3 10 49 21 16 55 27 27 41 59 47 16 9.0 12 72 20 17 40 27 30 52 142 73 16 8.7 28 51 20 19 33 25 31 43 --- 43 16 8.5 --- 40 --- 23 30 --- TOTAL 1770 2593 1264 657 389 324.0 473.7 2895 1059 841 1385 1435 MEAN 57.1 86.4 40.8 21.2 13.9 10.5 15.8 93.4 35.3 27.1 44.7 47.8 MAX 202 251 80 30 17 16 151 433 125 71 146 209 MIN 31 33 25 16 11 8.5 8.1 10 20 16 19 22 CFSM 3.48 5.27 2.49 1.29 .35 .64 .96 5.70 2.15 1.65 2.73 2.92 IN. 4.01 5.88 2.37 1.49 .38 .73 1.07 6.57 2.40 1.91 3.14 3.25 AC-FT 3510 5140 2510 1300 772 643 940 5740 2100 1670 2750 2850 CAL YR 1982 TOTAL 16381.0 MEAN 46.2 MAX 452 MIN 10 CFSM 2.32 IN 38.29 AC-FT 33480 WTR YR 1983 TOTAL 15085.7 MEAN 41.3 MAX 433 MIN 8.1 CFSM 2.52 IN 34.22 AC-FT 29920 WATER-QUALITY RECORDS PERIOD OF RECORD. --OCTOBER 1982 TO SEPTEMBER 1983 WATER-QUALITY DATA. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 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) OCT' 07 1015 37 235 22.5 APR. 14 1325 3.4 289 26.0 NOV, 10 1320 37 210 25.0 MAY. 12 1257 17 285 29.0 DEC. 22 1157 29 234 23.0 JUN. 09 0915 39 221 24.0 JAN. 12 1410 22 265 24.0 SEP. 08 0950 24 269 25.0 MAR, 17 1400 9.7 302 28.5 172 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°09'36", long 67°05'08", at bridge on Highway 348, 0.5 mi (0.8 km) southwest of Rosario plaza. DRAINAGE AREA.--18.3 sq mi (47.4 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM. TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW• CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANtE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV r 1982 04... 1030 40 265 8.3 24.0 1.5 8.8 107 <10 K500 330 JAN P 1983 13... 1155 30 273 8.4 23.0 <1.0 9.6 113 K530 240 APR 4... 1545 7.9 296 8.0 25.5 8.1 100 <10 430 MAY 5... 1400 42 204 8.2 25.5 18 8.1 101 17 4100 3500 AUG 18... 1150 44 233 8.3 25.5 15 8.7 107 16 5100 3100 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUD.*. HARD- NESS• CALCIUM SIUM, SODIUM• AD- SION, LINITY SULFATE RIDEr RIDE, NESS NONCAR- DIS DIS- DES- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV p 1982 04... 120 JAN r 1983 13... 130 3 25 17 3.6 .3 1.2 130 7.0 8.3 <.10 APR 4... 170 MAY 5... 98 7 18 13 7.0 .3 1.1 92 8.7 7.3 <.10 AUG 18... 110 1 21 13 6.5 .3 1.1 105 8.2 6.0 <.10 SOLIDS, SOLIDS. NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DM- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN. GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV s 1982 04... 4 <.010 .60 <.010 .30 .90 JAN r 1983 13... 31 176 14.3 12 <.010 .70 .020 .78 .80 1.5 APR 4... <.010 .10 .010 .39 .40 .50 MAY 5... 27 137 15.6 22 .79 .010 .80 .010 .19 .20 1.0 AUG 18... 27 146 17.5 16 .59 .010 .60 <.010 .20 .80 CHRO- BARIUM. CADMIUM MIUM. LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELF- TOTAL GEN, pHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L CMG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV r 1982 04... 4.0 .050 JAN , 1983 13... 6.6 .580 1 <100 2 24 2 <.1 <1 <1 APR 4... 2.2 .050 MAY 5... 4.4 .050 AUG 18... 3.5 .040 2 200 <1 11 6 <.1 <1 1 K = non-ideal count 173 RIO GUANAJIBO BASIN 50138000 RIO GUANAJIBO NEAR HORMIGUEROS, PR LOCATION.--Lat 18°08'36", long 67°08'57", Hydrologic Unit 21010003, at bridge on Highway 100, 1.4 mi (2.3 km) west of Hormigueros, and 2.0 mi (3.2 km) downstream from Rio Rosario. DRAINAGE AREA.--120 sq mi (311 sq km). WATER-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 mi (0.5 km) upstream at datum 7.36 ft (2.243 m) higher. REMARKS.--Records fair. AVERAGE DISCHARGE.--10 years (1974-83), 220 cu ft/s (6.230 cu m/s), 24.90 in/yr (632 mm/yr), 159,400 acre-ft/yr (197 cu hm/yr); median of yearly mean discharges, 204 cu ft/s (5.78 cu m/s), 148,000 acre-ft/yr (182 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 128,000 cu ft/s (3,625 cu m/s) Sept. 16, 1975, gage height, 28.50 ft (8.687 m), site and datum then in use, from rating curve extended above 100 cu ft/s (2.83 cu m/s) on the basis of contracted-opening measurement of peak flow; minimum, 4.6 cu ft/s (0.130 cu m/s) June 22, 1977. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 2,000 cu ft/s (56.6 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) May 19 0215 2,160 61.2 18.86 5.748 May 23 0545 *2,360 66.8 19.38 5.907 May 19 2330 2,090 59.2 18.66 5.688 Minimum discharge, 15 cu ft/s (0.425 cu m/s) Apr. 4. DISCHARGE• IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 162 419 437 73 39 23 17 82 172 54 41 76 2 206 504 230 70 38 23 16 75 162 86 49 71 3 144 377 192 65 36 22 16 62 209 80 37 66 4 126 288 170 63 35 22 16 67 207 150 102 70 5 122 385 158 61 36 24 16 141 145 208 74 78 6 112 290 143 58 35 28 17 68 126 111 41 70 7 112 180 131 57 35 30 17 201 156 77 35 66 8 112 200 123 55 33 30 33 225 192 64 33 62 9 115 400 159 53 32 25 44 98 138 57 54 57 10 90 600 129 51 32 23 25 74 122 64 53 209 11 85 300 115 43 31 21 20 70 109 71 67 311 12 80 250 106 47 30 83 19 61 99 90 43 160 13 79 300 102 46 29 99 18 166 90 60 144 109 14 99 200 98 47 29 65 18 692 83 51 158 93 15 112 166 92 61 29 42 16 243 79 48 106 86 16 88 420 92 50 29 32 17 153 77 48 64 105 17 72 1340 39 47 29 28 17 119 75 66 111 233 18 160 1520 85 45 29 25 20 540 82 85 153 199 19 933 990 97 44 29 23 19 1620 74 83 37 121 20 521 939 155 45 30 22 31 1480 68 59 221 100 21 314 620 98 42 35 22 1100 1180 65 51 380 92 22 220 422 92 42 30 21 219 2230 61 46 247 243 23 215 343 185 40 29 21 130 1310 59 43 158 351 24 174 353 143 39 28 21 143 783 56 42 168 226 25 148 540 113 38 28 20 95 687 54 38 423 173 26 460 353 105 37 27 20 78 573 52 34 381 150 27 570 276 97 36 25 19 66 354 53 33 206 134 28 222 286 89 36 24 19 146 281 51 34 152 123 29 186 246 92 37 --- 19 148 240 50 36 120 113 30 187 674 125 33 18 96 246 50 37 100 104 31 174 --- 106 42 17 --- 196 --- 41 86 --- TOTAL 6450 14186 4198 1518 871 907 2633 14327 3016 2047 4094 4051 MEAN 208 473 135 49.0 31.1 29.3 87.8 462 101 66.0 132 135 MAX 983 1520 487 78 39 99 1100 2230 209 208 423 351 MIN 72 166 35 36 24 17 16 61 50 33 33 57 CFSM 1.73 3.94 1.13 .41 .26 .24 .73 3.85 .34 .55 1.10 1.13 IN. 2.00 4.40 1.30 .47 .27 .28 .82 4.44 .93 .63 1.27 1.26 AC-FT 12790 28140 3330 3010 1730 1800 5220 28420 5980 4060 8120 8040 CAL YR 1982 TOTAL 66654 MEAN 183 MAX 6270 MIN 19 CFSM 1.53 IN 20.66 AC-FT 132200 WTR YR 1983 TOTAL 58298 MEAN 160 MAX 2230 MIN 16 CFSM 1.33 IN 18.07 AC-FT 115600 174 RIO GUANAJIBO BASIN 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 1982 TO SEPTEMBER 1983 DATE STREAM FLOW. INSTAN- TIME TANEOUS (CFS) SPE- CIFIC CON- DUCT- ANCE (UMHOS) PH (STAND- ARD UNITS) TEMPER- ATURE (DEG C) TUR- BID- ITY (NTU) OXYGEN. DIS- SOLVED (MG/L) OXYGEN, OXYGEN COLI- STREP- DIS- DEMAND, FORM, TOCOCCI SOLVED CHEM- FECAL, FECAL, (PER- ICAL 0.7 KF AGAR CENT (HIGH UM-MF (COLS. SATUR- LEVEL) (COLS./ PER AT ION) (MG/L) 100 ML) 100 ML) NOV , 1982 05... 0915 207 394 7.5 24.0 16 5.5 66 14 27000 K12000 JAN • 1983 14... 1000 46 490 8.0 23.0 5.5 7.0 82 38000 K4000 APR 4... 1255 15 519 7.4 25.0 3.9 108 <10 K1700 MAY 5... 1050 134 286 7.5 25.0 150 7.5 91 57 35000 53000 JUN 08... 1540 172 355 7.6 26.0 5.6 70 AUG 17... 1330 58 218 8.2 28.0 18 5.9 75 200 K85000 7400 HARD- NESS (MGM. AS DATE CAC03) HARD- NESS. NONCAR- BONATE (MG/L CAC03) CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM. DIS- SOLVED (MG/L AS NA) SODIUM POTAS- ALKA- AD- SIUM, LINITY SORP- DIS- FIELD TION SOLVED (MG/L RATIO (MG/L AS AS K) CAC03) SULFATE DIS- SOLVED (MG/L AS SO4) CHLO- FLUO- RIDE, RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CL) AS F) NOV • 1932 05... JAN • 1983 14... 210 APR 4... MAY 5... 130 JUN 08... AUG 17... 180 170 3 31 33 17 .5 2.0 210 22 20 .20 220 15 21 20 12 .5 1.8 120 14 11 .10 150 1 29 26 16 .5 1.8 179 15 15 .20 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN. GEN' MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE 5IO2) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 OS... JAN e 1983 14... APR 4... MAY 5... JUN 08... AUG 17... 32 .37 .030 .40 .170 .23 .40 .80 32 283 35.2 22 .71 .090 .80 .350 .05 .40 1.2 .47 .030 .50 .520 .28 .80 1.3 25 177 64.0 307 .78 .120 .90 .360 .54 .90 1.8 31 241 37.8 22 .76 .040 .80 .230 .57 .80 1.6 K = non-ideal count 175 RIO GUANAJIBO BASIN 50138000 RIO GUANAJIBO NEAR HORMIGUEROS, PR - -Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHRO- BARIUM, CADMIUM MIUM. LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN. PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM. RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERA3LE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS PS) AS HG) AS SE) AS AG) NOV 1982 05... 3.5 .290 JAN r 1983 14... 5.3 .520 1 100 1 15 4 .1 <1 <1 APR 4... 5.8 .570 MAY 5... 8.0 .300 JUN 08... AUG 17... 7.1 .440 2 100 1 10 4 <.1 <1 <1 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) OCT, 06 1355 113 428 27.5 FEB. OS 1450 32 452 25.0 DEC. 22 1530 92 495 25.0 SEP, 07 1510 66 422 28.0 CHLOR- DI- PCB, ALDRIN. DANE. ODD, DDE. DDT. AZINON. TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UM) (UG/L) (UG/L) (UG/L) JUN r 1983 08... 1540 (.10 <.01 <.10 <.01 <.01 <.01 .02 HEPTA- METH- DI- ENDO- HEPTA- CHLOR MALA- OXY­ ELDRIN SULFANe ENDRIN. ETHIONe CHLOR. EPDXIDE LINDANE THION. CHLOR. TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN e 1983 08... <.01 <.01 <.01 <.01 <.01 <.01 <.01 .02 <.01 NAPH­ THA­ METHYL METHYL LENESe PARA- TRI- PARA- POLY'. PER- TOX- TOTAL THION. THION. MIREX. THION. CHLOR. THANE APHENE. TRI­ TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL THION DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN r 1983 08... <.01 <.01 <.01 <.01 <.10 <.10 <.01 <1 Coastal bosi Drainage boundary Rio Culebrinas basin FLARES Rio GrOnd Rio Guajot000 basin Rio Camuy basin Rio Tanamd basin MAYA L•VO ranuoca 1410 ,e; /Orre Coastal basin Rio Guonojibo basin MARICAO al Drainage boundary as a 14 o 4. • ac § Rio Youco basin Guayimil basin \Island EXPLANATION A1410 SURFACE—WATER STATION AND NUMBER A1389 LOW—FLOW STATION AND NUMBER Y1385 QUALITY—OF—WATER STATION AND NUMBER • 45 WELL AND WELL NUMBER .A0UADIL L A eA.E. Map area___ '1.1.(*i,. 2 3 4 5 6 TKILOMETERS I hMILES Figure 24.--Rio Yaguez and Rio Grande de glasco basins. 178 RIO YAGUEZ BASIN 50138800 RIO YAGUEZ NEAR MAYAGUEZ, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°12'31", 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 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS.". CENT (HIGH UM-MF (COLS. TIME TANEOUS JUICE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 4... 0745 9.3 318 8.0 22.0 2.5 7.9 92 19 20000 3300 JAN , 1983 13... 1445 6.0 311 8.3 23.5 <1.0 9.6 114 3500 520 MAR 30... 1510 1.1 305 8.2 26.5 <1.0 10.2 127 <10 K130 750 MAY 5... 0710 1.4 298 7.6 24.0 <1.0 7.4 88 16 530 10000 AUG 18... 1430 9.3 268 8.0 27.0 18 7.1 89 11 2300 5200 HARD- NESS (MG/L AS DATE CAC03) HARD- NESS, NONCAR- BONATE (MG/L CAC03) CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM' DIS- SOLVED (MG/L AS MG) SODIUM, DIS- SOLVED (MG/L AS NA) SODIUM POTAS- ALMA- CHLO- FLUO- AD- SIUM, LINITY SULFATE RIDE, RIDE, SORP- DIS- FIELD DIS- DIS- DIS- TION SOLVED (MG/L SOLVED SOLVED SOLVED RATIO (MG/L AS (MG/L (MG/L (MG/L AS K) CAC03) AS SO4) AS CL) AS - F) NOV , 1982 4... 140 JAN , 1983 13... 130 0 35 10 12 .5 2.4 140 9.0 9.7 .10 MAR 30... 140 MAY 5... 140 0 37 11 15 .6 2.4 140 11 11 .10 AUG 18... 110 0 30 8.7 9.4 .4 1.9 111 8.2 7.8 <.10 SOLIDS. SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- GENeAM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Co NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL- TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) CMG/L) AS N) AS N) AS N) AS N) AS N) AS N) NOV , 1982 4... 6 <.010 .80 <.010 .40 1.2 JAN , 1983 13... 31 193 3.1 10 <.010 .70 .010 <.10 MAR 30... <1 <.010 .10 .010 .09 .10 .20 MAY 5... 27 198 .77 <1 <.010 .30 <.010 <.10 AUG 18... 27 160 4.0 12 <.010 .60 <.010 .10 .70 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER. NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, CHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV". RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERA3LE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS 3A) AS CD) AS CR) AS PB) AS HG) AS SE) AS ...,G) NOV , 1982 4... 5.3 .050 JAN , 1983 13... .570 1 200 1 8 2 <.1 <1 <1 MAR 30... .89 .030 MAY 5... .030 AUG 18... 3.1 .010 1 100 <1 6 5 <.1 <1 <1 K = non-ideal count 179 RIO GRANDE DE ARASCO BASIN 50141000 RIO BLANCO NEAR ADJUNTAS, PR LOCATION.--Lat 18°12'19", long 66°48'01", Hydrologic Unit 21010003, on right bank near dirt road off Highway 129, 0.4 mi (0.6 km) north- northwest of Highways 129 and 135 junction, 2.5 mi (4 km) northeast of Castailer, 2.3 mi (3.7 km) east-southeast of Lago Guayo Dam, and 0.5 mi (0.8 km) upstream from Rio Limani. DRAINAGE AREA.--15.4 sq mi (40.1 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1946 to December 1966 in reports of the Puerto Rico Water Resources Authority as "Rio Yahuecas near Adjuntas"; June 1980 to current year. GAGE.--Water-stage recorder. Altitude of gage is about 1,530 ft (466 m) from USGS topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.--23 years (1947-66, 81-83), 37.4 cu ft/s (1.059 cu m/s), 32.98 in/yr (838 mm/yr), 27,100 acre-ft/yr (33.4 cu hm/yr); median of yearly mean discharges, 37 cu ft/s (1.05 cu m/s), 26,800 acre-ft/yr (33 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 17,000 cu ft/s (481 cu m/s) Oct. 13, 1954, gage height unknown, minimum, 5.6 cu ft/s (0.158 cu m/s) Mar. 24, 1983. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 1,700 cu ft/s (48.1 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Oct. 14 1745 2,000 56.6 10.52 3.206 Apr. 21 0245 *5,350 152 13.37 4.075 Oct. 18 1945 5,010 142 13.13 4.002 Minimum discharge, 5.6 cu ft/s (0.158 cu m/s) Mar. 24. DISCHARGE, IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 31 25 20 19 19 23 22 22 21 20 29 26 24 24 23 13 18 17 17 18 11 8.7 6.8 11 8.3 6.7 11 8.3 6.6 11 8.4 6.2 11 8.4 6.8 16 15 15 16 15 16 15 16 15 14 13 12 12 14 20 8.9 9.0 14 30 12 11 11 11 9.9 10 6 7 8 9 10 19 96 29 21 19 21 23 21 20 20 21 21 21 20 21 17 17 16 16 16 11 8.4 9.8 11 8.2 7.4 10 8.6 6.8 10 8.4 6.8 10 8.5 6.7 15 14 14 14 22 13 51 21 16 15 15 12 12 15 13 9.1 8.1 16 16 21 29 20 15 39 21 11 12 13 14 15 19 18 30 179 55 23 61 46 25 24 21 19 19 19 25 15 15 15 15 16 9.9 7.9 6.7 9.6 64 6.9 9.5 20 7.4 9.5 12 15 9.6 10 20 16 21 39 26 21 15 14 13 13 13 1,4 12 11 10 10 13 11 11 12 14 45 24 17 14 14 16 17 18 19 20 30 26 348 112 65 45 107 53 55 39 22 19 19 24 37 15 14 14 14 14 9.3 8.7 12 9.6 3.1 9.1 9.4 8.1 22 9.1 7.9 13 9.4 7.7 48 16 15 71 33 21 18 38 64 25 19 12 19 14 11 10 9.9 46 24 13 41 13 45 50 34 18 21 22 23 24 25 45 38 30 26 25 34 36 31 48 30 24 21 19 19 19 14 13 13 13 12 11 7.5 576 9.9 7.2 34 9.4 7.2 23 9.1 7.3 20 9.0 7.3 18 43 57 35 41 54 17 16 14 14 13 9.9 9.6 9.8 10 8.8 37 25 16 14 31 16 35 55 55 28 26 27 28 29 30 31 24 25 26 27 30 24 31 40 31 27 39 --- 25 25 20 23 20 19 12 12 12 12 12 11 9.1 7.5 16 9.1 7.4 16 9.0 7.6 15 --- 7.2 29 7.2 18 7.0 --- 42 26 22 20 19 17 13 13 13 12 12 --- 8.5 8.5 8.5 9.0 11 9.5 18 14 13 12 11 11 20 21 20 32 20 --- TOTAL MEAN MAX MIN CFSM IN. AC-FT 1500 48.4 348 18 3.14 3.62 2980 1043 34.8 107 20 2.26 2.52 2070 688 22.2 37 19 1.44 1.66 1360 453 14.6 18 11 .95 1.09 899 277.5 319.0 995.7 9.91 10.3 33.2 11 64 576 9.0 7.0 6.2 .64 .67 2.16 .67 .77 2.41 550 633 1970 316 26.3 71 14 1.71 1.97 1620 561 18.7 64 12 1.21 1.36 1110 364.1 11.7 20 8.5 .76 .88 722 541.0 17.5 46 8.1 1.14 1.31 1070 752.9 25.1 55 9.9 1.63 1.82 1490 CAL YR 1982 WTR YR 1983 TOTAL TOTAL 11759.2 8311.2 MEAN 32.2 MEAN 22.3 MAX MAX 1110 MIN 9.2 CFSM 2.09 576 MIN 6.2 CFSM 1.48 IN IN 28.40 20.08 AC-FT AC-FT 23320 16490 WATER-QUALITY RECORDS PERIOD OF RECORD.--MARCH 1946 TO DECEMBER 1966 IN REPORTS OF THE PUERTO RICO WATER RESOURCES AUTHORITY AS "RIO YAHUECAS NEAR ADJUNTAS"; JUNE 1980 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW. SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TORE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMHOS) (DEG C) OCT, 04 0855 19 239 22.0 APR, 13 0850 7.2 269 19.0 NOV, 09 1030 20 254 22.0 MAY. 11 0945 16 232 19.0 DEC. 20 1255 38 180 20.0 JUN. 08 1100 21 207 25.0 JAN. 11 0945 15 232 19.0 SEP, 06 1105 10 262 26.5 MAR. 16 1032 9.0 257 22.5 180 RIO GRANDE DE ARASCO BASIN 50141100 LAGO YAHUECAS NEAR CASTARER, PR LOCATION.--Lat 18°13'20", long 66°49'15", Hydrologic Unit 21010003, at Yahuecas Dam on Rio Blanco, 1.1 mi (1.8 km) northeast of Lago Guayo, 2.8 mi (4.5 km) northeast of Castaiier, 3.8 mi (6.1 km) northeast of Lago Prieto, and about 4 mi (6 km) northwest of Adjuntas. DRAINAGE AREA.--17.4 sq mi (45.1 sq km). ELEVATION RECORDS PERIOD OF RECORD.--April 1980 to current year. GAGE.--Water-stage recorder. Datum of gage is 1,400.00 ft (426.720 m) above mean sea level. REMARKS.--Lago Yahuecas was completed in 1956. The dam is a unit of the southwestern Puerto Rico project and provides a maximum storage of 1,800 ac-ft (2.22 cu hm) for power and irrigation. The dam is a concrete gravity structure with a total length of 450 ft (137.2 m), a maximum structural height of 90 ft (27.4 m), and a maximum base width of 60 ft (18.3 m). The spillway is an ungated overflow type with a crest elevation of 71.00 ft (21.641 m) and a crest length of 200 ft (61.0 m); It was designed to pass a maximum flood of 38,000 cu ft/s (1,076 cu m/s) at a reservoir elevation of 84.00 ft (25.603 m). Timber flashboards, originally installed on the spillway crest, were subsequently removed and their use discontinued. Diversions are conveyed to Lago Guayo by an 11 ft (3.4 m) diameter, 6,470 ft (1,972 m) long tunnel, mostly unlined. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation, 76.61 ft (23.351 m) Sept. 13, 1982; minimum, 48.42 ft (14.758 m) Feb. 4, 1981. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 73.79 ft (22.491 m) Apr. 21; minimum, 51.36 ft (15.654 m) June 28. Capacity table (elevation, in feet, and contents, in acre-feet) (based on data from Puerto Rico Water Resources Authority) 30 0 65 1,000 49 393 71 1,308 60 778 75 1,540 ELEVATION (FEET NGV0), WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 2400 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 71.27 71.14 71.10 71.23 70.50 68.12 68.92 70.86 70.68 52.83 51.80 A 2 71.17 71.10 71.10 71.21 70.50 68.04 63.72 70.62 70.34 52.39 51.90 3 71.12 71.06 71.11 71.23 70.50 67.92 68.49 70.35 70.29 52.54 55.52 4 71.09 71.03 71.12 71.23 70.01 67.78 68.27 70.45 69.90 52.82 55.48 5 71.06 71.01 71.13 71.28 70.09 67.63 68.02 70.33 69.45 53.56 53.26 A 6 71.10 71.00 71.13 71.36 70.01 67.60 67.94 70.23 69.01 53.61 53.37 56.14 7 71.33 71.02 71.14 71.18 69.77 67.43 67.74 70.01 70.45 52.61 53.38 53.60 3 71.13 71.00 71.15 71.20 69.66 67.40 67.53 69.74 70.32 52.50 54.75 53.68 9 71.14 71.07 71.16 71.13 69.56 67.32 67.31 69.54 69.98 54.11 52.88 53.60 10 71.12 71.01 71.20 71.25 69.42 A 67.18 70.58 69.29 53.67 56.74 58.79 11 71.12 71.06 71.21 70.90 69.27 67.98 70.72 68.24 53.07 53:15 54.52 12 71.11 71.58 71.16 71.04 69.12 66.81 71.13 67.27 53.23 53.00 54.60 13 71.29 71.10 71.05 71.01 69.01 66.72 71.26 61.26 52.78 53.19 54.38 14 71.47 71.03 71.20 71.03 68.89 66.69 71.22 58.55 52.78 54.69 54.17 15 71.20 71.03 71.28 71.10 68.79 66.69 71.14 57.31 52.78 53.21 54.22 16 71.24 71.34 71.19 71.10 68.68 70.45 67.44 71.01 55.23 53.10 52.96 55.50 17 71.24 71.39 71.16 70.98 68.60 70.50 67.18 70.93 55.44 54.22 56.94 60.80 18 71.39 71.18 71.18 70.97 68.49 70.51 67.57 71.37 55.54 53.17 54.38 19 71.43 71.24 71.31 70.92 63.41 70.57 67.64 71.19 55.60 53.35 54.22 20 71.38 71.16 71.37 70.92 68.12 70.58 69.54 71.13 55.48 53.51 54.35 21 71.31 71.07 71.31 70.78 68.25 70.58 71.37 71.45 55.01 52.84 54.30 22 71.31 71.13 71.33 70.70 68.23 70.49 71.23 71.36 54.64 52.50 61.06 23 71.29 71.03 71.31 70.84 68.21 70.40 71.17 71.22 54.32 52.24 56.72 24 71.27 71.17 71.30 70.69 63.20 70.25 71.12 71.29 53.75 52.24 54.25 25 71.26 71.12 71.34 70.82 68.24 70.10 71.01 71.49 51.69 52.36 54.09 26 71.34 71.19 71.35 70.87 63.20 69.96 70.34 71.23 51.87 51.87 54.01 27 71.24 71.17 71.21 70.86 68.25 69.82 70.62 71.13 51.62 51.93 54.02 28 71.18 71.13 71.23 70.83 68.18 69.65 70.41 71.13 51.74 52.20 54.03 29 71.37 71.11 71.40 70.71 --- 69.47 71.07 71.14 51.81 51.79 54.23 30 71.18 71.19 71.33 70.71 69.27 71.08 71.13 51.88 52.14 54.16 31 71.17 --- 71.29 70.66 69.09 --- 70.96 --- 52.17 TOTAL 2208.82 2133.85 2207.85 2200.84 1933.16 2064.30 2197.39 1817.96 1636.91 MEAN 71.25 71.13 71.22 70.99 69.04 68.81 70.88 60.60 52.80 MAX 71.69 71.58 71.40 71.36 70.50 71.37 71.49 70.68 54.22 MIN 71.06 71.00 71.05 70.66 68.12 66.69 69.54 51.62 51.79 A No gage-height record. 181 RIO GRANDE DE ARASCO BASIN 50141500 LAGO GUAYO NEAR CASTARER, PR LOCATION.--Lat 18°12'46", long 66°50'06", Hydrologic Unit 21010003, at Guayo Dam on Rio Guayo, 1.1 mi (1.8 km) southwest of Lago Yahuecas, 2.6 mi (4.2 km) southwest of Lago Prieto, 2.1 mi (3.4 km) north of Castafier, and 6.0 mi (9.6 km) west of Adjuntas. DRAINAGE AREA.--9.60 sq mi (24.9 sq km). ELEVATION RECORDS PERIOD OF RECORD.--April 1980 to current year. GAGE.--Water-stage recorder. Datum of gage is 1,400.00 ft (426.720 m) above mean sea level. REMARKS.--Lago Guayo was completed in 1956. The dam is on Rio Guayo and is the largest in the southwestern Puerto Rico project. The maximum storage is 17,400 ac-ft (21.5 cu hm) for power and irrigation. The dam is a concrete gravity structure with a total length of 555 ft (169.2 m), a maximum structural height of 190 ft (57.9 m), and a maximum width at the base of 145 ft (44.2 m). The ungated overflow spillway with a crest elevation of 60.00 ft (18.288 m) and a crest length of 220 ft (67.1 m) was designed to pass a maximum flood of 30,200 cu ft/s (855 cu m/s) at a reservoir elevation of 70.00 ft (21.336 ft). Timber flashboards that were added to increase storage capacity were subsequently removed and their use discontinued. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation, 62.43 ft (19.029 m) May 27, 1980; minimum, 35.13 ft (10.708 m) Jan. 20, 1981. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 61.04 ft (18.605 m) Apr. 21; minimum, 45.95 ft (14.001 m) Nov. 5. Capacity table (elevation, in feet, and contents, in acre-feet) (based on data from Puerto Rico Water Resources Authority) 30 6,530 60 13,550 49 10,660 65 15,000 ELEVATION (FEET NGVO), WATER YEAR OCTOBER 1982 TO SEPTEMBER INSTANTANEOUS OBSERVATIONS AT 2400 1983 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 53.92 41.22 53.67 59.32 60.07 60.01 59.50 60.08 59.74 51.59 51.57 51.27 2 59.22 47.12 53.37 59.46 60.06 59.91 59.35 60.07 59.43 51.82 51.17 51.02 3 4 59.46 59.70 46.46 46.26 54.07 54.25 59.62 59.73 60.07 60.09 59.77 59.62 59.20 59.16 60.07 60.10 59.27 59.57 52.04 52.35 51.65 52.28 51.20 51.01 5 59.93 46.04 54.44 59.93 60.07 59.51 59.26 60.08 59.82 52.75 52.49 51.17 6 60.11 46.43 54.63 60.05 60.08 59.33 59.37 60.13 59.99 53.02 52.64 50.90 7 8 9 10 60.23 60.22 60.20 60.18 46.77 47.12 46.89 46.60 54.80 54.98 55.15 55.32 60.06 60.09 60.08 60.05 60.08 60.07 60.08 60.08 59.22 59.10 58.94 58.78 59.46 59.55 59.63 59.71 60.09 60.09 60.C7 60.20 59.85 59.82 59.43 58.38 52.10 52.31 52.56 52.80 52.78 52.21 52.00 52.29 50.39 49.70 49.53 51.21 11 60.16 46.83 55.48 60.03 60.06 58.65 59.81 59.93 59.15 53.05 52.69 52.03 12 13 14 15 60.17 60.28 60.47 60.20 47.81 49.47 48.87 48.56 55.66 55.84 56.01 56.23 60.03 60.08 60.10 60.09 60.07 60.07 60.07 60.08 58.77 58.67 58.54 58.47 59.88 59.99 60.05 60.12 59.70 59.63 60.04 60.13 59.40 59.31 58.58 57.31 53.26 52.66 52.79 52.52 52.53 52.73 53.01 52.14 52.33 51.94 50.58 49.49 16 17 18 19 20 60.14 60.13 60.35 60.30 60.17 49.37 49.26 49.44 49.98 50.65 56.41 56.59 56.74 56.99 57.22 60.09 60.03 60.08 60.10 60.09 60.08 60.08 60.09 60.11 60.09 58.54 53.60 58.69 58.76 58.83 60.08 60.08 60.09 60.08 60.37 60.08 60.05 60.30 60.64 59.41 55.20 54.16 55.11 55.49 55.38 52.76 53.14 53.13 53.32 53.49 51.62 52.27 52.99 52.32 52.98 48.73 48.62 48.35 47.62 47.04 21 22 23 24 25 60.16 59.61 53.64 57.65 56.11 51.19 51.57 51.79 52.06 52.31 57.37 57.54 57.72 57.88 58.05 60.09 60.08 60.09 60.07 60.08 60.08 60.08 60.08 60.07 60.07 58.91 58.99 59.07 59.16 59.23 60.20 60.10 60.10 60.08 60.07 60.49 60.27 60.16 59.23 59.80 55.04 54.63 54.30 53.58 51.39 52.76 52.03 52.27 52.44 52.59 53.69 53.17 52.69 52.09 52.53 47.00 48.07 48.99 49.58 49.77 26 27 54.28 53.56 52.53 52.77 58.32 58.50 60.07 60.07 60.07 60.06 59.30 59.40 60.07 60.07 59.83 59.48 51.53 51.50 52.07 52.22 51.42 51.67 49.55 48.97 28 52.47 53.00 58.66 60.06 60.05 59.48 60.07 58.81 51.53 52.36 51.91 47.90 29 30 31 51.27 50.22 49.25 53.21 53.46 --- 58.34 59.00 59.17 60.07 60.07 60.07 --- 59. 9659 59.66 60.08 60.07 --- 59.70 59.77 59.97 51.41 51.35 --- 51.86 52.09 52.11 52.11 51.75 51.22 48.04 47.43 --- TOTAL MEAN MAX MIN 1804.29 58.20 60.88 49.25 1481.09 49.37 53.46 46.04 1749.40 56.43 59.17 53.67 1860.16 60.01 60.10 59.32 1682.11 60.08 60.11 60.05 1833.22 59.14 60.01 58.47 1795.65 59.86 60.37 59.16 1858.40 59.95 60.64 58.81 1691.15 56.37 59.99 51.35 1628.31 52.53 53.49 51.59 1620.61 52.28 53.69 51.17 1489.43 49.65 52.33 47.00 CAL YR 1982 TOTAL 19010.20 MEAN 52.08 MAX 60.83 MIN 35.65 WTR YR 1983 TOTAL 20493.82 MEAN 56.15 MAX 60.83 MIN 46.04 182 RIO GRANDE DE MASCO BASIN 50142500 LAGO PRIETO NEAR CASTARER, PR LOCATION.--Lat 18°11'08", long 66°51'48", Hydrologic Unit 21010004, at dam on Rio Prieto, 2.0 mi (3.2 km) west of Castaner, 3.1 mi (5.0 km) southwest of Lago Guayo, 3.8 mi (6.1 km) southwest of Lago Yahuecas, and about 9 mi (14 km) west of Adjuntas. DRAINAGE AREA.--9.60 sq mi (24.9 sq km). ELEVATION RECORDS PERIOD OF RECORD.--May 1980 to current year. GAGE.--Water-stage recorder. Datum of gage is 1,400.00 ft (476.720 m) above mean sea level. REMARKS.--Lago Prieto was completed in 1955. It provides a maximum storage of approximately 700 ac-ft (0.863 cu hm) for power and irrigation. A power tunnel adit from the reservoir to the Lago Guayo tunnel allows for releases to Power Plant No. 1. Turbine releases are collected in Lago Antonio Lucchetti and are reused for power generation at Power Plant No. 2. The dam is a concrete gravity structure with a total length of 260 ft (79.2 m), a maximum structural height of 98 ft (29.9 m), and a maximum base width of 65 ft (19.8 m). The ungated overflow spillway, with a crest elevation of 85.00 ft (25.908 m), and a crest length of 170 ft (51.8 m) was designed to pass a maximum flood of 32,000 cu ft/s (906 cu m/s). Timber flashboards that were added after initial construction were subsequently removed, and their use discontinued. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation, 87.49 ft (26.667 m) Sept. 13, 1982; minimum, less than 55.05 ft (16.779 m) many days. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 83.10 ft (25.329 m) May 19; minimum, less than 52.60 ft (16.032 m) most days. Capacity table (elevation, in feet, and contents, in acre-feet) (based on data from Puerto Rico Water Resources Authority) 49 0 85 484 60 97 90 586 65 156 ELEVATION (FEET NGVD). WATER YEAR OCTO3ER 1982 TO SEPTEM3ER 1983 INSTANTANEOUS 03SERVATIONS AT 2400 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 59.38 62.96 C 2 59.36 60.99 3 59.60 62.26 4 59.78 60.75 5 59.95 60.63 6 60.03 60.28 53.58 7 60.20 60.10 53.66 8 60.18 59.86 53.23 9 10 60.22 60.15 59.43 59.04 52.64 C 57.54 11 60.18 60.27 59.10 54.00 54.20 12 13 60.22 60.52 65.62 69.28 59.55 59.46 53.96 53.87 54.16 53.01 14 15 60.94 60.14 71.78 71.92 57.69 54.29 52.96 16 60.15 55.17 71.85 52.61 17 18 19 60.16 71.09 60.35 69.53 68.77 79.89 60.05 54.04 52.75 20 60.11 63.91 55.38 21 22 23 24 25 60.14 57.32 56.92 55.88 A 74.79 66.88 66.33 64.98 66.54 53.58 54.87 53.96 54.08 52.62 52.61 62.12 53.71 54.05 52.98 26 65.64 52.70 52.62 27 28 29 30 B 62.10 62.42 63.55 63.00 52.61 52.61 52.61 52.61 52.61 31 63.32 C C TOTAL MEAN MAX MIN A No gage-height record. 8 Stage below elevation 55.05 ft. C Stage below elevation 52.60 ft. AS N) AS N) AS N) AS N) AS N) 1.6 .050 1.3 1.30 2.9 .50 .030 <.10 .40 .020 .18 .20 .60 .60 .050 .25 .30 .90 .60 .020 .48 .50 1.1 DATE SI02) (MG/L) DAT) (MG/L) AS N) AS N) NOV r 1982 10... JAN , 1983 31... MAR 23... MAY 11... AUG 24... 85 26 170 20.2 1 6 21 145 33.6 24 30 205 12.2 8 1.6 .040 <.010 .39 .010 .58 .020 .58 .020 AS NO3) AS 1982 13 1983 P) .090 AS AS) AS BA) .040 1 100 2.7 .030 4.0 .070 4.9 .040 2 100 AS CD) AS CR) AS P3) AS HG) AS SE) AS AG) 3 3 .3 <1 <1 <1 4 <.1 <1 <1 DATE NOV , 10... JAN , 31... MAR 23... MAY 11... AUG 24... 183 RIO GRANDE DE A1ASCO BASIN 50143000 RIO GRANDE DE A1ASCO NEAR LARES, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°15'26", long 66°55'00", 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 during 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 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL. FLOW, CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMMOS) UNITS) (DEC C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 10... JAN , 31... MAR 23... MAY 11... AUG 24... 85 2.3 1.1 30 4.5 1982 0845 63 223 7.8 22.0 1983 1720 44 282 7.9 24.0 0835 16 320 8.1 24.5 1520 86 232 8.2 29.0 0915 22 298 6.3 26.0 7.9 92 26 22000 K15000 8.2 99 16 K44 K88 8.6 105 18 K94 580 7.1 94 14 3300 2900 12.3 154 78 220 230 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- OIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV • 1932 10... JAN • 1983 31... 120 10 32 9.8 12 .5 MAR 23... MAY 11... 96 3 26 7.5 9.4 .4 AUG 24... 120 0 34 9.4 13 .5 77 1.7 110 13 9.4 <.10 130 2.5 93 13 9.4 <.10 1.5 140 23 9.8 <.10 SOLIDS, SOLIDS. NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO-_ NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN. GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY SILVER, NITRO- PHOS- TOTAL TOTAL TOTAL TOTAL TOTAL SELE- TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- NIUM, RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L K . non-ideal count 184 RIO GRANDE DE ARASCO BASIN 50144000 RIO GRANDE DE A8ASCO NEAR SAN SEBASTIAN, PR LOCATION.--Lat 18°17'05", long 67°03'05", Hydrologic Unit 21010003, on left bank, 200 ft (61 m) downstream from bridge on Highway 108, 0.4 mi (0.6 km) downstream from Quebrada La Zumbadora, 4.4 mi (7.1 km) northwest of Las Marias, 5.4 mi (8.7 km) southwest of San Sebastign. DRAINAGE AREA.--94.3 sq mi (244.2 sq km), does not include 36.2 sq mi (93.8 sq km) which contributes only during high floods, and 3.5 sq mi (9.1 sq km) 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 cu hm). Limited storm runoff is contributed to basin by 3.5 sq mi (9.1 sq km) above Rio Toro Diversion dam. AVERAGE DISCHARGE.--20 years (1964-83), 304 cu ft/s (8.609 cu m/s), 43.78 in/yr (1,112 mm/yr), 220,200 acre-ft/yr (272 cu hm/yr); median of yearly mean discharges, 301 cu ft/s (8.52 cu m/s), 218,000 acre-ft/yr (269 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 140,000 cu ft/s (3,965 cu m/s) Sept. 16, 1975, gage height, 33.9 ft (10.33 m), from rating curve extended above 4,000 cu ft/s (113 cu m/s) on basis of slope-area measurement; minimum, 31 cu ft/s (0.878 cu m/s) Apr. 19-20, 1965, gage height, 0.88 ft (0.268 m). EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 6,000 cu ft/s (170 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Nov. 18 1715 6,340 180 7.46 2.274 May 18 0830 6,710 190 7.67 2.338 Apr. 21 0815 *8,000 227 8.36 2.548 Minimum discharge, 53 cu ft/s (1.501 cu m/s) Apr. 4, 9-11. DISCHARGE. IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 292 191 322 167 114 85 56 108 219 162 98 124 2 302 182 258 159 114 83 56 98 236 182 88 110 3 258 175 243 151 113 75 56 96 865 106 82 107 4 216 167 237 150 111 73 54 138 668 102 147 102 5 283 162 228 150 116 71 56 265 390 194 111 93 6 326 168 220 146 116 83 58 143 272 128 97 95 7 325 190 214 151 114 75 57 477 236 100 81 168 3 387 172 210 160 111 72 55 300 243 91 127 112 9 306 447 206 157 108 72 54 172 204 86 190 333 10 269 692 203 154 105 70 53 131 265 179 121 169 11 230 277 203 149 105 69 56 232 192 297 234 389 12 218 243 198 147 100 100 58 148 178 191 201 193 13 210 348 192 145 100 199 58 183 155 109 220 131 14 278 204 190 143 100 104 62 251 143 92 579 107 15 726 356 192 157 102 85 102 209 136 83 355 107 16 358 985 204 164 102 73 206 170 128 125 196 102 17 304 1570 185 163 102 73 115 248 121 350 422 380 18 315 1800 175 164 103 70 100 1530 131 202 374 432 19 1760 776 194 153 100 69 106 877 118 132 179 274 20 634 539 299 146 103 63 117 802 112 105 141 143 21 395 428 262 136 115 67 2620 1260 110 92 211 122 22 323 383 179 134 102 63 311 1600 104 87 202 289 23 242 365 168 132 96 63 153 723 98 127 140 472 24 215 556 164 132 96 64 129 594 96 109 166 482 25 206 581 157 127 97 64 108 624 92 90 127 228 26 198 348 162 123 92 64 93 668 93 87 223 161 27 203 325 174 123 91 62 36 359 108 82 226 172 28 212 319 167 113 89 59 31 255 95 82 190 159 29 223 282 233 115 --- 59 121 344 103 144 143 273 30 245 295 359 116 53 132 491 174 116 128 163 31 215 --- 202 119 57 --- 270 --- 98 126 --- TOTAL 10674 13526 6599 4461 2917 2359 5369 13771 6085 4130 5925 6192 MEAN 344 451 213 144 104 76.1 179 444 203 133 191 206 MAX 1760 1800 359 163 116 199 2620 1600 865 350 579 482 MIN 198 162 157 115 89 57 53 96 92 82 31 93 CFSM 3.65 4.78 2.26 1.53 1.10 .81 1.90 4.71 2.15 1.41. 2.03 2.19 IN. 4.21 5.34 2.60 1.76 1.15 .93 2.12 5.43 2.40 1.63 2.34 2.44 AC-FT 21170 26830 13090 8350 5790 4680 10650 27310 12070 8190 11750 12280 CAL YR 1982 TOTAL 107145 MEAN 294 MAX 6630 MIN 79 CFSM 3.12 IN 42.27 AC-FT 212500 WTR YR 1983 TOTAL 82008 MEAN 225 MAX 2620 MIN 53 CFSM 2.39 IN 32.35 AC-FT 162700 185 RIO GRANDE DE ASASCO BASIN 50144000 RIO GRANDE DE ARASCO 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 1982 TO SEPTEMBER 1983 TIME DATE OXYGEN. COLT- STREP- SPE- On- FORM, TOCOCCI HARD- STREAM- CIFIC SOLVED FECAL, FECAL. HARD- NESS. FLOW, CON- PH TUR- OXYGEN, (PER- 0.7 KF AGAR NESS NONCAR- INSTAN- DUCT- (STAND- TEMPER- SID- DIS- CENT UM-MF (COLS. (MG/L BONATE TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- (COLS./ PER AS (MG/L (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) 100 ML) 100 ML) CAC03) CAC03) OCT . 1982 07... 1225 280 156 7.8 25.0 100 8.1 99 11800 6400 74 0 FEB . 1983 01... 0900 112 249 7.5 22.0 2.6 8.9 102 K100 330 110 1 JUN 16... 1130 129 253 8.4 29.0 6.6 7.8 102 K190 82 100 4 AUG 03... 1340 83 237 8.0 30.5 12 8.1 109 210 84 100 1 SOLIDS. MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, RESIDUE CALCIUM srum, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, DIS- AT 180 DIS- DIS- DIS- SORP- ors- FIELD DIS- DIS- DIS- SOLVED DEG. C SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L OIS- (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS SOLVED DATE AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) SI02) (MG/L) OCT r 1932 07... 18 7.0 7.7 .4 1.1 30 10 6.1 (.10 23 130 FEB . 1983 01... 28 10 12 .5 1.3 110 10 7.5 <.10 30 155 JUN 16... 26 9.4 10 .4 1.8 100 10 7.6 .10 30 157 AUG 03... 25 9.2 9.7 .4 1.7 100 11 7.2 .10 29 152 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED DATE (MG/L) SOLIDS, DIS- SOLVED (TONS PER DAY) NITRO- GEN. NO2+NO3 DIS- SOLVED (MG/L AS N) NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS N) NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) NITRO- GEN/AM- MONIA + ORGANIC TOTAL (MG/L AS N) PHOS- PHORUS, TOTAL (MG/L AS P) PHOS- PHORUS TOTAL (MG/L AS PO4) PHOS- PHORUS. DIS- SOLVED (MG/L AS P) PHOS- PHORUS, ORTHO. DIS- SOLVED (MG/L AS P) PHOS- PHATE. ORTHOr DIS- SOLVED (MG/L AS PO4) OCT r 1982 07... 121 98.3 .93 .030 .04 .70 .070 .21 .030 .030 .09 FEB . 1983 01... 165 46.9 .60 .030 .04 <.10 .060 .18 .030 .030 .09 JUN 16... 155 5f..7 .39 .030 .04 .40 .020 .06 .020 .020 .06 AUG 03... 153 34.1 .23 .050 .06 .30 .040 .12 .060 .030 .09 ALUM- BERYL- CHRO- INUM, DIS- ARSENIC DIS- BARIUM, DIS- LIUM. DIS- CADMIUM DIS- MIUM, DIS- COBALT. DIS- COPPER. DIS- IRON. DIS- LEAD, DIS- LITHIUM DIS- SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS AL) AS AS) AS 8A) AS BE) AS CD) AS CR) AS CO) AS Cu) AS FE) AS PB) AS LI) OCT r 1982 07... <10 1 44 <1 <1 <1 <3 3 17 <1 <4 FEB r 1933 01... 10 1 50 <1 <1 <1 <3 6 <3 3 <4 JUN 16... 30 1 52 1 1 1 3 <1 3 <1 4 AUG 03... 200 K = non-ideal 1 count 50 <1 <1 <1 <3 6 12 4 <4 RIO GRANDE DE ARASCO BASIN 50144000 RIO GRANDE DE ARASCO NEAR SAN SEBASTIAN, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 SEDI- MANGA- MOLYB- SELE- STRON- YANA- MENT, NESE, MERCURY DENUM, NICKEL, NIUM, SILVER, T/UM, DIUM, ZINC, SEDI- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- DIS- MENT, CHARGE, SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SOLVED SUS- SUS- (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L PENDED PENDED DATE AS MN) AS HG) AS MO) AS NI) AS SE) AS AG) AS SR) AS V) AS ZN) (MG/L) (T/DAY) OCT 1982 07... 8 <.1 <10 2 <1 <1 99 <6.0 <4 154 116 FEB , 1983 01... 15 .1 <10 3 <1 <1 150 <6.0 16 9 2.7 JUN 16... 19 <.1 10 2 <1 <1 140 6.0 67 23 8.0 AUG 03... 26 <.1 <10 3 <1 <1 130 <6.0 <3 5 1.1 186 STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) ,(DEG C) NOV, 05 1235 60 284 26.0 DEC, 21 1512 202 252 24.0 JAN, 04 1100 148 283 23.0 FEB, 01 0845 112 248 22.0 STREAM-FLOW, SPECIFIC CON- DATE TIME INSTANTANEOUS DUCTANCE (CFS) (UMHOS) MAR, 10 1610 69 245 APR, 11 1300 53 250 MAY, 04 1120 87 312 SEP, 01 1150 117 331 TEMPERA- TURE (DEG C) 28.0 27.0 27.0 28.0 DATE STREAM- FLOW, INSTAN- TIME TANEOUS (CS) SED. SUSP. SEDI- SIEVE MENT, DIAM. SUS- X FINER PENDED THAN CMG/L) .062 MM OCT , 1932 07... 1225 280 154 96 FEB , 1983 01... 0900 112 9 78 JUN 16... 1130 129 23 94 AUG 03... 1340 33 5 100 BED MAT. STREAM- SIEVE FLOW, DIAM. INSTAN- FINER TIME TANEOUS THAN DATE (CFS) .062 MM AUG , 1983 03... 0955 E32 2 E = estimate 187 RIO GRANDE DE ARASCO BASIN 50146000 RIO GRANDE DE AIASCO NEAR ARASCO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°16'00", long 67°08'05", at bridge on Highway 430, 0.2 mi (0.3 km) south of Highway 109 at a El Espino and 1.4 mi (2.3 km) east-southeast from Aiiasco plaza. DRAINAGE AREA.--139 sq mi (360 sq km) this does not include 39.7 sq mi (102.8 sq km), flow is diverted to south coast. PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN. OXYGEN COLT- STREP- SPE- DIS- DEMAND, FORM. TOCOCCI STREAM- CIFIC FECAL. FECAL, FLOW. SOLVED CHEM- CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER- BID- DIS-CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 05... 1250 217 255 8.0 27.0 15 9.0 115 <10 400 K30 JAN . 1933 14... 1310 300 258 7.8 24.0 20 8.7 105 200 K88 MAR 30... 0905 59 235 8.2 25.5 1.2 8.4 103 <10 K47 150 MAY 12... 1140 179 240 7.6 25.5 38 7.8 96 13 2200 K700 JUN 08... 1215 256 234 8.0 27.0 AUG 19... 1000 600 225 7.4 26.0 50 7.6 93 24 K1500 3600 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS. CALCIUM SIUM, SODIUM. AD- SIUM, LINITY SULFATE RIDE, RIDE. NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L 80NATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CACO3) AS SO4) AS CL) AS F) NOV I 1982 05... JAN • 1983 14... 100 MAR 30... MAY 12... 97 JUN 03... AUG 19... 90 100 0 26 9.4 9.7 .4 1.7 110 9.0 7.5 <AO 110 0 25 8.3 8.7 .4 2.2 97 13 8.0 (.10 98 1 23 7.8 8.0 .4 1.3 89 10 6.3 <.10 SOLIDS, SOLIDS. NITRO- SILICA. SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GENrAM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN. GEN, MONIA + SOLVED TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (Mt/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) NITRO- GE N. TOTAL (MG/L AS N) NOV r 1982 05... 30 JAN r 1983 14... 29 158 128 34 MAR 30... 3 MAY 12... 23 151 73.2 55 JUN 08... AUG 19... 26 136 221 100 K = non-ideal count <.010 .40 .060 .64 .70 1.1 .59 .010 .60 .040 .26 .30 .90 <.010 <.10 <.010 <.10 .63 .020 .70 .050 .25 .30 1.0 9.1 .450 9.5 .070 .33 .40 9.9 RIO GRANDE DE ARASCO BASIN 50146000 RIO GRANDE DE A8ASCO NEAR ARASCO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHRO— BARIUM. CADMIUM MIUM, LEAD. MERCURY SILVER, NITRO— PHOS— TOTAL TOTAL TOTAL TOTAL TOTAL SELE— TOTAL GEN, PHORUS. ARSENIC RECOV— RECOV— RECOV— RECOV— RECOV— NIUM. RECOV— TOTAL TOTAL TOTAL ERABLE ERABLE ERA9LE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS 3A) AS CD) AS CR) AS PB) AS HG) AS SE) AS AG) NOV r 1982 05... 4.9 .050 JAN , 1983 14... 4.0 .600 1 100 2 17 6 .2 <1 <1 MAR 30... .020 MAY 12... 4.4 .080 JUN 08... AUG 19... 44 .040 2 100 1 6 3 (.1 <1 <1 CHLOR— DI— PCB. ALDRIN, DANE, ODD. DOE, DDT. AZINON, TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN e 1983 03... 1215 <.10 <.01 <.10 <.01 <.01 <.01 <.01 HEPTA— METH— DI— ENDO— HEPTA— CHLOR MALA— OXY— ELDRIN SULFAN, ENGRIN. ETHION, CHLOR, EPDXIDE LINDANE THION, CHLOR, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN • 1983 08... <.01 <.01 <.01 <.01 <.01 <.01 (.01 <.01 <.01 METHYL METHYL PARA— PARA— THION. THION. MIREX, THION, TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) NAPH— THA— LENES. POLY— PER— TOX— TOTAL CHLOR. THANE APHENE. TRI— TOTAL TOTAL TOTAL THION (UG/L) (UG/L) (UG/L) (UG/L) JUN . 1983 08... <.01 <.01 <.01 <.01 <.10 <.10 <1 <.01 188 AGUADILLA Drainage boundary uncertain Nro 6uoyabo ----•• GU DA 00 1478 RINCON • Coastal basin Coastal basin Rio Grande de AIlasco basin LARES U ---' 20—r:inage boundary \\ EXPLANATION A1478 SURFACE WATER STATION AND NUMBER A 1462 LOW—FLOW STATION AND NUMBER -1476 QUALITY—OF—WATER STATION AND NUMBER • 83 WELL AND WELL NUMBER v—Map area SAN JUAN PONCE Figure 25.--Rio Culebrinas basin. OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHEM- (PER- ICAL CENT (HIGH SATUR- LEVEL) ATION) (MG/L) COLI- STREP- FORM, TOCOCCI FECAL, FECAL, 0.7 KF AGAR UM-MF (COLS. (COLS./ PER 100 ML) 100 ML) OXYGEN, DIS- SOLVED (MG/L) 7.8 91 20 K19000 6700 7.7 90 32 K6800 5800 8.7 118 29 K170 K90 7.4 92 16 47000 K170000 7.5 93 11 K6000 3400 190 RIO CULEBRINAS BASIN 50147600 RIO CULEBRINAS NEAR SAN SEBASTIAN, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°20'51", long 67°02'40", at bridge on Highway 423, 1.3 mi (2.1 km) south of Quebrada El Salto Bridge on Highway 111, and 2.1 mi (3.4 km) west of Central La Plata. DRAINAGE AREA.--58.2 sq mi (150.7 sq km). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 SPE- STREAM- CIFIC FLOW, CON- PH TUR- INSTAN- DUCT- (STAND- TEMPER- BID- TIME TANEOUS ANCE ARD ATURE ITT DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) NOV . 1932 18... 0820 96 304 7.8 22.0 15 JAN r 1983 19... 0910 51 309 7.8 23.0 2.9 MAR 22... 1545 16 325 8.4 31.0 1.3 MAY 12... 0720 68 314 7.5 26.0 28 AUG 25... 0905 82 291 8.0 26.0 8.0 SULFATE DIS- SOLVED (MG/L AS 504) HARD- MAGNE- SODIUM HARD- NESS,. CALCIUM SIUM, SODIUM, AD- NESS NONCAR- 015- On- DIS- SORP- (MG/L 80NATE SOLVED SOLVED SOLVED TION AS (MG/L (MG/L (MG/L (MG/L RATIO DATE CAC03) CAC03) AS CA) AS MG) AS NA) POTAS- 4LKA- STUN, LINITY DIS- FIELD SOLVED (MG/L (MG/L AS AS K) CAC03) CHLO- FLUO- RIDE, RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CL) AS F) NOV . 1932 18... JAN . 1983 19... 120 MAR 22... MAY 12... 120 AUG 25... 120 120 5 40 6.0 19 .8 2.4 120 16 12 .10 130 4 40 5.7 14 .6 3.4 120 21 12 .10 5 39 5.1 13 .5 2.0 114 14 11 .10 SOLIDS, SOLIDS, NITRO- SILICA, SUM OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- CIS- CONSTI- MS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + SOLVED TUENTS, SOLVED DEG. Co NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) AS N) NITRO- GEN, TOTAL (MG/L AS N) NOV 1982 13... JAN p 1983 19... 32 199 27.2 MAR 22... MAY 12... 32 200 36.7 AUG 25... 30 183 40.5 14 1.1 .040 1.1 .100 .70 .80 1.9 1 1.2 .110 1.3 .160 .44 .60 1.9 11 .28 .020 .30 .920 .88 1.80 2.1 34 .62 .080 .70 .160 .34 .50 1.2 12 1.1 .080 1.2 .060 .14 .20 1.4 CHRO- BARIUM, CADMIUM MIUM, LEAD, MERCURY NITRO- PHDS- TOTAL TOTAL TOTAL TOTAL TOTAL GEN, PHORUS, ARSENIC RECOV- RECOV- RECOV- RECOV- RECOV- TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS P8) AS HG) SELE- NIUM, TOTAL (UG/L AS SE) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) NOV 1982 18... 3.4 .080 JAN 1983 19... 8.4 .190 2 <100 1 1 MAR 22... 9.3 .500 MAY 12... 5.3 .190 AUG 25... 6.2 .100 2 100 1 <1 K = non-ideal count 14 .6 <1 <1 4 <.1 <1 <1 191 RIO CULEBRINAS BASIN 50147800 RIO CULEBRINAS AT HIGHWAY 404 NEAR MOCA, PR LOCATION.--Lat 18°21'42", long 67°05'33", Hydrologic Unit 21010003, on right bank, at bridge on Highway 404, 0.3 mi (0.5 km) downstream from Quebrada Yagruma, and 2.8 mi (4.5 km) southeast of Moca. DRAINAGE AREA.--71.2 sq mi (184.4 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.---July 1967 to current year. GAGE.--Water-stage recorder. Altitude of gage is 45 ft (13.7 m), from topographic map. REMARKS.--Records fair. AVERAGE DISCHARGE.---16 years (1968-83), 299 cu ft/s (8.468 cu m/s), 57.03 in/yr (1,449 mm/yr), 216,600 acre-ft/yr (267 cu hm/yr); median of yearly mean discharges, 286 cu ft/s (8.10 cu m/s), 207,000 acre-ft/yr (255 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 69,000 cu ft/s (1,954 cu m/s) Sept. 16, 1975, gage height, 36.6 ft (11.16 m) from slope-area measurement, but may have been exceeded by flood of Oct. 23, 1974, from rating curve extended above 2,600 cu ft/s (73.6 cu m/s) on basis of slope-area and contracted-opening measurements of peak flow; minimum, 16 cu ft/s (0.453 cu m/s) Apr. 17-19, 1979. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 11,300 cu ft/s (320 cu m/s) and maximum (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Nov. 18 2030 15,800 447 24.42 7.443 Aug. 17 1845 *18,600 527 25.48 7.766 June 13 1830 13,800 390 23.59 7.190 Minimum discharge, 18 cu ft/s (0.510 cu m/s) Apr. 13. DISCHARGE, IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 230 134 150 121 53 36 23 324 229 150 86 286 2 174 126 129 109 52 35 25 273 178 122 65 137 3 137 121 122 100 51 36 24 236 159 110 61 113 4 149 123 123 96 51 35 21 314 150 95 67 103 5 378 117 115 93 52 35 23 3C2 150 100 63 97 6 191 425 109 83 53 33 21 180 240 109 66 89 7 134 290 107 85 51 38 22 119 189 88 58 383 8 129 1060 104 82 47 35 21 158 180 33 78 512 9 150 393 100 81 46 36 23 80 324 76 178 1540 10 120 734 102 79 46 33 19 77 407 74 71 281 11 114 335 99 76 46 31 20 57 807 113 64 441 12 111 390 95 75 44 31 20 191 993 169 56 476 13 106 296 94 72 44 43 24 1090 2510 93 267 377 14 104 168 95 63 45 33 22 1180 1490 76 292 240 15 205 209 118 69 45 32 39 343 560 72 496 288 16 178 165 106 63 41 32 71 653 300 109 446 176 17 431 138 90 71 38 29 30 488 238 158 3830 228 18 413 3110 87 66 38 27 27 569 206 92 624 332 19 825 711 135 73 38 30 24 415 165 BO 249 206 20 369 406 217 79 43 26 104 189 423 74 180 143 21 857 199 104 64 56 29 705 337 210 71 135 131 22 321 173 95 62 43 27 71 338 145 67 170 136 23 195 157 89 62 41 27 64 332 126 79 129 165 24 170 742 35 62 41 26 43 624 113 93 114 644 25 152 300 34 60 40 27 35 1150 106 63 105 1540 26 142 171 164 58 42 24 28 812 102 61 142 281 27 135 155 172 63 40 26 26 703 179 60 198 441 23 729 160 143 58 38 25 24 551 120 58 172 476 29 244 167 553 56 --- 25 60 480 337 80 167 377 30 155 158 710 56 25 94 308 230 86 445 240 31 142 --- 178 55 24 --- 316 --- 79 481 --- TOTAL 7890 11838 4674 2307 1265 956 1753 13699 11566 2 .345 9655 10879 MEAN 255 395 151 74.4 45.2 30.8 58.4 442 336 91.3 311 363 MAX 857 3110 710 121 56 43 705 1180 2510 169 3880 1540 MIN 104 117 84 55 38 24 19 57 102 58 56 89 CFSM 3.58 5.55 2.12 1.05 .64 .43 .82 6.21 5.42 1.29 4.37 5.10 IN. 4.12 6.18 2.44 1.21 .66 .50 .92 7.16 6.04 1.' - 5.04 5.68 AC-FT 15650 23480 9270 4580 2510 1900 3480 27170 22940 5640 19150 21580 CAL YR 1982 TOTAL 111821 MEAN 306 MAX 5520 MIN 44 CFSM 4.30 IN 58.42 AC-FT 221800 WTR YR 1983 TOTAL 79327 MEAN 217 MAX 3880 MIN 19 CFSM 3.05 IN 41.45 AC-FT 157300 WATER-QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1933 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA­ DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (DEG C) (CFS) (UMNOS) (DEG C) OCT, 06 0900 175 172 23.0 MAR. 17 0930 25 287 25.5 NOV, 10 0900 206 177 23.0 APR, 14 0920 20 273 24.5 DEC. 23 1113 89 249 24.0 MAY. 12 0840 99 354 26.5 FEB, 08 1012 48 270 22.0 JUN. 06 1330 227 372 -- JAN. 12 1025 76 270 23.0 SEP, 07 1035 129 288 26.0 MAR, 17 0930 25 297 25.5 192 RIO CULEBRINAS BASIN 50149100 RIO CULEBRINAS NEAR AGUADA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°24'03", long 67°09'40", at bridge on Highway 2, and 2.3 mi (3.7 km) northeast of Aguada plaza. DRAINAGE AREA.--97.0 sq mi (251.2 sq km). PERIOD OF RECORD.--Water years 1958, 1970 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLT- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL. FLOW. CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND- TEMPER.... BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITT SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) NOV , 1982 17... 1300 206 332 7.7 24.5 28 7.2 87 24 4200 5500 JAN , 1983 19... 1230 88 234 7.9 25.0 4.1 7.8 94 25 K380 440 MAR 22... 1315 32 480 7.3 34.0 <1.0 .0 0 26000 13000 MAY 12... 0915 90 478 7.4 29.0 5.8 5.3 69 38 44000 K18000 JUN 08... 0925 236 355 7.7 26.0 7.1 88 AUG 25... 1300 153 338 7.8 28.5 19 6.9 89 66 980 600 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS, CALCIUM SIUM. SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L 80NATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) NOV . 1982 17... 130 JAN , 1983 19... 130 0 41 6.1 15 .6 2.3 130 9.0 11 <.10 MAR 22... 220 MAY 12... 180 0 58 8.3 20 .7 8.9 190 24 21 .10 JUN 08... 150 AUG 25... 140 2 48 5.9 13 .5 2.1 142 12 13 .10 SOLIDS, SOLIDS, NITRO- SILICA, SUN OF SOLIDS, RESIDUE NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, MONIA + NITRO- SOLVED TUENTS, SOLVED DEG. Cr NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) , AS N) AS N) NOV . 1982 17... 51 .77 .030 .80 .070 .63 .70 1.5 JAN • 1983 19... 33 195 46.4 2 .68 .020 .70 .060 .44 .50 1.2 MAR 22... 8 .010 <.10 .490 1.0 1.50 MAY 12... 28 282 63.6 10 .45 .050 .50 .300 .40 .70 1.2 JUN 08... AUG 25... 30 209 86.4 28 .78 .020 .80 .090 .51 .60 1.4 K = non-ideal count 193 RIO CULEBRINAS BASIN 50149100 RIO CULEBRINAS NEAR AGUADA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 C4120— BARIUM, CADMIUM MIUMe LEAD, MERCURY SILVER, NITRO— PHOS— TOTAL TOTAL TOTAL TOTAL TOTAL SELE— TOTAL GEN, PHORUSe ARSENIC RECOV— RECOV— RECOV— RECOV— RECOV— NIUM, RECOV— TOTAL TOTAL TOTAL ERABLE ERABLE ERABLE ERABLE ERABLE TOTAL ERABLE (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS AS) AS BA) AS CD) AS CR) AS P8) AS HG) AS SE) AS AG) NOV , 1982 17... 6.6 .110 JAN r 1983 19... 5.3 .060 1 <100 1 <1 13 .3 <1 <1 MAR 22... 3.00 MAY 12... 5.3 .760 JUN 08... AUG 25... 6.2 .090 2 100 1 <1 10 (.1 <1 <1 CHLOR— DI— PCB, ALORIN, DANE, ODD, ODE, ODTe AZINON. TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN , 1983 08... 0925 <.10 <.01 <.10 <.01 <.01 <.01 .01 HEPTA— METH— DI— ENDO— HEPTA— CHLOR MALA— OXY— ELDRIN SULFANe ENORINe ETHION, CHLOR. EPDXIDE LINDANE THION, CHLORe TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN r 1983 08... <.01 <.01 <.01 <.01 <.01 <.01 <.01 <.01 <.01 NAPH— THA— METHYL METHYL LENESe PARA— TRI— PARA— POLY— PER— TOX— TOTAL THION, THION, MIREX, THION, CHLOR. THANE APHENEr TRI— TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL THION DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUN r 1983 08... <.01 <.01 <.01 <.01 <.10 <.10 <1 <.01 195 DISCHARGE AT PARTIAL-RECORD STATIONS As the number of streams on which streamflow information is likely to be desired far exceeds the number of stream-gaging stations feasible to operate at one time, the Geological Survey collects limited steamflow data at sites other than stream-gaging stations. When limited streamflow data are collected on a systematic basis over a Period of years for use in hydrologic analyses, the site at which the data are collected is called a partial-record station. Data collected at these partial-record stations are useable in low-flow or floodflow analyses, depending on the type of data collected. In addition, discharge measurements are made at other sites not included in the partial- record program. These measurements are generally made in times of drought or flood to give better areal coverage to those events. Those measurements and others collected for some special reason are called measurements at miscellane- ous sites. Records collected at partial-record stations are presented in two tables. The first is a table of dis- charge measurements at low-flow partial-record stations and the second is a table of annual maximum stage and dis- charge at crest-stage stations. Low-flow partial-record stations measurements of streamflow in the areas covered by this report made at low-flow partial-record stations are given in the following table. These measurements were made during periods of base flow when streamflow is primar- ily from ground-water storage. These measurements, when correlated with the simultaneous discharge of nearby stream when continuous records are available, will give a picture of the low-flow potentiality of stream. STATION NUMBER Discharge measurements made at low-flow partial-records stations during water year 1983 PUBLICATION RECORD STATION LOCATION DRAINAGE Q SP TEMPER- AREA cu ft/s NAME AND sq mi DATE TIME COND ATURE (cu BASIN (sq km) m/s) umhos deg C Quabrada de los Cedros basin 50007000 Cuebrada de los Cedros Lat 18 30 46, long 67 05 47 near Isabela, PR Hydrologic unit 21010002. On dirt road, 4.7m1 (7.6km) west of Isabela, and 0.5 mi (0.8 km) upstream from mouth. Rio Guajataca basin 6.91 2/28/33 1150 DRY (17.90) 50011400 Rio Guajataca above mouth near Quebradillas, PR Let 15 28 31, long 66 57 46 Hydrologic unit 21010002. At ford, 1.7 mi (2.7 km) up- stream from bridge on Hwy 2, 2.1 mi (3.4 km) from the Atlantic Ocean, 6.6 mi (10.6 km) downstream from Lago Guajataca, and 1.6 mi (2.6 km) west of Quebradi- llas. 23.7 3/30/83 1000 11.3 25.0 (61.4) (0.32) 50015800 Rio Camuy basin Rio Camuy at Capaez, PR Lai 18 27 49, long 66 49 58 Hydrologic unit 21010002. At 1.1 mi (1.7 km) south of Purification Plant of Nati- llo, about 1.4 mi (2.2 km) south of Hwy 2, and 1.8 mi (2.9 km) upstream from mouth. 22.0 3/01/33 1520 45.9 345 25.0 (57.0) (1.30) Rio Cibuco basin 50039000 Rio Indio near Vega Baja, Let 18 26 19, long 66 22 13 PR Hydrologic unit 21010002. At bridge on Hwy 160, 0.6 mi 26.7 3/04/83 0940 10.0 450 25.0 (1.0 km) upstream from Rio (69.2) (0.28) Cibuco, and 1.2 mi (1.9 km) southeast of Vega Baja. Rio de la Plata basin 50045800 Rio Lajas at Toa Alta, Let 13 23 39, long 66 15 16 PR Hydrologic unit 21010005. At bridge on Hwy 165, 0.2 mi (0.3 km) upstream from Rio de la Plata, and 0.5 mi (0.8 km) northwest of Toa Alta. Rio Hondo basin 8.60 3/04/83 1120 2.55 550 27.0 (22.27) (0.07) 50047502 Rio Hondo at Bayamon, PR Let 18 23 51, long 66 09 22 Hydrologic unit 21010005. At bridge on Hwy 2, 700 ft (213 m) east of Hwy 2 and 7.59 3/08/83 1330 22.2 550 27.5 Calle Parque intersection. (19.66) (0.63) and 0.7 mi (1.2 km) south of sewage treatment plant. 50047504 Cuebrada Santa Catalina Lat 13 24 05, long 66 09 43 at Bayamon, PR Hydrologic unit 21010005. 700 ft (213 m) downstream from bridge on Hwy 2 and 0.2 mi (0.3 km) upstream from mouth. 2.50 (6.47) 3/08/83 1015 0.67 1060 25.5 (0.02) 50047508 Cano de Cuebrada Catalina at Bayamon, PR Lat 18 24 27, long 66 09 38 Hydrologic unit 21010005. At bridge on new Hwy 167, 0.7 mi (1.1 km) north of Hwy 2 and Calle Parque intersec- tion, and 0.2 mi (0.3 km) upstream from sewage treat- ment plant. 0.65 3/03/83 1038 0.09 430 25.0 (1.68) (0.002) DISCHARGE AT PARTIAL-RECORD STATIONS 196 Low-flow partial-record stations--Continued STATION STATION LOCATION DRAINAGE Q SP TEMPER- AREA cu ft/s NUMBER NAME AND sq mi DATE TIME COND ATURE (cu BASIN (sq km) m/s) umhos deg C Rio Hondo basin 50047525 Rio Hondo II near Bayamon, PR Lat 13 25 19, long 66 10 38 Hydrologic unit 21010005. At bridge on Hwy 572 and 0.7 mi (1.1 km) downstream from bridge on Hwy 22. 3.18 3/08/83 1120 1.37 540 25.5 (8.24) (0.04) Rio de Bayamon basin 50048510 Rio de Bayamon at Flood Lat 13 24 29, long 66 09 04 Channel at Bayamon, PR Hydrologic unit 21010005. At bridge on Hwy 890, 1.0 mi (1.6 km) downstream from bridge on Hwy 2, and 3.2 mi (5.1 km) upstream from mouth. 73.2 (189.6) 3/10/33 0905 28.4 460 25.0 (0.80) 50049000 Rio Piedras at Rio Piedras, PR 50049310 Quebrada Josefina at Pinero Avenue, PR Rio Puerto Nuevo basin Lat 18 23 43, long 66 03 24 Hydrologic unit 21010005. On left bank, at bridge on Hwy 1, 0.3 mi (0.5 km) 12.5 3/04/83 0815 2.59 345 26.0 southwest of Rio Piedras (32.4) (0.07) Plaza, and 0.4 mi (0.6 km) downstream from diversion for water supply. Lat 13 24 33, long 66 04 36 Hydrologic unit 21010005. At bridge on Pinero Aver and 0.4 mi (0.6 km) upstream 19.0 3/04/83 0900 10.6 404 26.0 from junction with Rio Pie- (49.2) (0.30) dras. 50049600 Quebrada Margarita at Let 18 24 33, long 66 06 18 Caparra Heights, PR Hydrologic unit 21010005. At bridge on Franklin D. Roosevelt Ave, at San Pa- tricio Plaza and Fort Bu- channan interchange with Hwy 2, and 0.1 mi (0.2 km) south of Caparra Heights. Quabrada Blasina basin 50050300 Quebrada Blasina near Lat 13 23 27, long 65 53 28 Carolina, PR Hydrologic unit 21010005. At bridge on Hwy 3, 1.4 mi (2.3 km) south of Valle A- rriba Heights, and 1.2 mi (1.9 km) west-southwest of Carolina. Rio Grande de Loiza basin 1.82 3/04/83 1028 2.65 490 28.5 (4.71) (0.03) 2/28/83 0805 5.17 613 26.5 2.96 (0.15) (7.67) 7/29/83 0855 9.60 430 27.5 (0.27) 50051010 Rio Grande de Loiza below Rio Emajagua, PR Lat 13 07 23, long 65 59 18 Hydrologic unit 21010005. 200 ft (61 m) below junc- tion with Rio Emajagua and 400 ft (122 m) north of Hwy 181 and Hwy 745 intersection. 2/23/83 0945 15.9 140 24.5 12.2 (0.45) (31.6) 7/25/83 1007 43.3 124 25.5 (1.23) 2/28/83 1050 21.3 175 25.0 17.8 (0.60) (46.1) 7/25/83 1129 53.7 160 26.5 (1.52) 50051140 Rio Grande de Loiza at Lat 18 09 29, long 65 58 48 Jagual, PR Hydrologic unit 21010005. 200 ft (61 m) east of Jagual School on Hwy 181 and 1.7 mi (2.8 km) above junction with Rio Cayaguas. 50052300 Rio Grande de Loiza at Lat 13 11 39, long 65 57 46 San Lorenzo North, PR Hydrologic unit 21010005. Above sewage treatment plant 46.0 on north side of San Lorenzo, (119.1) 0.2 mi (0.3 km) northwest of the plaza, and 1.6 mi (2.6 km) downstream from Rio Cayaguas. 50052700 Rio Grande de Loiza at Lat 18 12 22, long 65 59 23 Hwy 183, PR Hydrologic unit 21010005. 2.1 mi (3.4 km) northwest of Plaza de San Lorenzo and 1.8 mi (2.9 km) downstream from bridge on Hwy 181. 50052900 Quebrada las Bambuas at Lat 13 13 31, long 66 00 58 mouth, PR Hydrologic unit 21010005. 300 ft (91 m) upstream from bridge on Hwy 183 and 900 ft (275 m) above junction with Rio Grande de Loiza. 2/28/83 1222 42.9 215 27.5 (1.21) 7/25/33 1248 102 166 29.0 (2.89) 50.9 (131.8) 2.33 (6.03) 2/28/33 1350 47.9 250 29.0 (1.36) 7/25/83 1421 106 176 31.0 (3.00) 3/03/33 1340 0.67 580 27.5 (0.02) 7/26/83 1338 0.85 576 30.0 (0.02) DISCHARGE AT PARTIAL-RECORD STATIONS 197 Low-flow partial-record stations--Continued STATION STATION LOCATION DRAINAGE Q SP TEMPER- AREA cu ft/s NUMBER NAME AND sq mi DATE TIME CONO ATURE (Cu BASIN (sq km) m/s) umhos deg C Rio Grande de Loiza basin 50053050 Rio Turabo at Borinquen, Lat 18 10 11. long 66 02 37 PR Hydrologic unit 21010005. 3/03/83 0900 8.17 165 23.0 At bridge on Hwy 765 and 7.79 (0.23) 1.2 mi (1.9 km) north of (20.18) Escuela Anon. 7/26/83 0848 13.0 148 25.5 (0.51) 50053300 Quebrada Beatriz above Lat 18 11 15. long 66 03 04 Rio Turabo, PR Hydrologic unit 21010005. 3/03/83 1005 3.35 285 24.5 1,400 ft (425 m) downstream 5.65 (0.09) from bridge on Hwy 765 and (14.63) 400 ft (120 m) above junction 7/26/83 1000 4.29 274 27.0 with Rio Turabo. (0.12) 50053500 Rio Turabo below Lat 18 11 22. long 66 03 02 Quebrada 8eatriz, PR Hydrologic unit 21010005. 3/03/83 1100 13.3 250 26.0 0.9 mi (1.4 km) downstream 17.3 (0.38) from bridge on Hwy 765 and (44.8) 400 ft (120 m) below junction 7/26/83 1049 23.9 223 28.5 with Quebrada Beatriz. (0.68) 50054500 Rio Turabo at Caguas, PR Lat 18 13 36, long 66 01 40 3/03/33 1245 9.27 370 28.0 Hydrologic unit 21010005. 29.3 (0.26) At bridge on Hwy 183, 0.9 mi (75.9) (1.5 km) southeast of the 7/26/83 1242 23.2 279 30.0 plaza in Caguas. and 1.3 mi (0.66) (2.1 km) upstream from Rio Grande de Loiza. 50055310 Rio Caguitas above mouth, Let 18 15 22. long 66 01 06 3/02/83 1205 14.5 850 28.5 PR Hydrologic unit 21010005. 18.0 (0.41) 0.5 mi (0.7 km) downstream (46.6) from bridge on Hwy 30 and 7/28/83 1055 15.9 621 29.0 0.4 mi (0.7 km) above junc- (0.45) tion with Rio Grande de Loiza. 50055410 Rio Bairoa at mouth, PR Lat 18 15 47, long 56 01 09 3/02/83 1340 3.37 560 30.0 Hydrologic unit 21010005. 7.51 (0.10) 0.8 mi (1.2 km) downstream (19.45) from bridge on Hwy 30 and 7/28/83 1142 4.15 460 29.0 0.4 mi (0.6 km) above junc- (0.12) tion with Rio Grande de Loiza. 50055500 Quebrada Honda at Las Lat 13 13 15, long 65 49 57 Torres, PR Hydrologic unit 21010005.At bridge on Hwy 31, 100 ft 1.15 2/28/83 DRY - (30 m) east of Hwy 31 and (2.98) Hwy 936 intersection, and 7/25/83 1225 0.11 902 28.0 1.8 mi (2.9 km) above junc- (0.003) tion with Rio Gurabo. 50055600 Rio Gurabo at Ceiba Lat 13 13 29, long 65 51 34 Norte, PR Hydrologic unit 21010005. 2/28/33 0930 2.20 - 27.0 0.4 mi (0.6 km) downstream 12.0 (0.06) from bridge on Hwy 31 and (31.1) 0.2 mi (0.4 km) below junc- 7/25/83 1130 10.8 291 28.5 tion with Quebrada Honda. (0.31) 50055700 Rio Gurabo at El Mango, Let 18 13 56, long 65 52 52 3/01/83 1130 3.56 485 28.0 PR Hydrologic unit 21010005. 16.5 (0.10) 1.2 mi (2.0 km) upstream (42.7) from bridge on Hwy 31 and 7/27/83 1425 7.89 425 25.0 0.2 mi (0.4 km) above junc- (0.22) tion with Quebrada Grande. 50056000 Rio Valenciano near Las Lat 18 10 37, long 65 54 21 3/01/83 0935 6.74 200 24.0 Piedras, PR Hydrologic unit 21010005. 6.85 (0.19) At bridge on Hwy 183 (km (17.74) 17.3), and 3.2 mi (5.1 km) 7/27/83 1040 17.3 323 27.5 west of Las Piedras. (0.49) 50056550 Rio Valenciano at mouth, Lat 18 14 13, long 65 55 13 3/01/83 1255 12.8 430 28.0 PR Hydrologic unit 21010005. 19.0 (0.36) 0.6 mi (1.0 km) downstream (49.2) from bridge on Hwy 31 and 7/27/83 1635 25.7 360 25.0 1,000 ft (305 m) above junc- (0.73) tion with Rio Gurabo. 50056600 Rio Gurabo near Juncos, Let 18 14 38, long 65 55 25 PR Hydrologic unit 21010005. 3/01/83 1400 18.0 440 28.5 At bridge on Hwy 185 and 50.0 (0.51) 0.4 mi (0.6 km) below junc- (129.5) tion with Rio Valenciano. 7/28/83 1312 37.1 432 30.0 (1.05) 50057015 Rio Gurabo below Hwy 943, Lat 18 15 50, long 65 58 41 PR Hydrologic unit 21010005. 3/04/83 1140 17.9 440 28.0 0.6 mi (0.9 km) northeast of 62.4 (0.51) Plaza de Gurabo and 0.7 mi (161.6) (1.2 km) downstream from 7/28/83 1425 44.0 478 29.5 bridge on Hwy 181. (1.25) 198 DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations--Continued STATION STATION LOCATION DRAINAGE Q SP TEMPER- AREA cu ft/s NUMBER NAME AND sq mi DATE TIME COND ATURE (Cu BASIN (sq km) m/s) umhos deg C Rio Grande de Loiza basin 50058400 Rio Canas above Lago Loiza. PR Lat 18 17 34. long 66 02 33 Hydrologic unit 21010005. At bridge about 2000 ft (610 m) off Hwy 1. 1.0 mi (1.6km) upstream from Lago Loiza. 1.0 mi (1.6 km) north of La Barra. and 4.0 mi (6.4 km) north of Caguas. 3/02/83 1020 3.54 300 25.0 7.63 (0.10) (19.76) 7/28/83 0955 3.80 342 26.0 (0.11) 50059000 Lago Loiza at Dam Site. Lat 18 19 49. long 66 01 00 PR Hydrologic unit 21010005. At pumphouse at damsita and 1.9 mi (3.1 km) south of Trujillo Alto Plaza. 50059200 Quebrada Grande at La Lat 18 20 28. long 65 59 20 Gloria. PR Hydrologic unit 21010005. 400 ft (122 m) downstream from bridge on Hwy 181. 200 ft (61 m) below junction with Quebrada Grand.. and 1.5 mi (2.4 km) above junc- tion with Rio Grande de Loi- za. 3/02/83 0910 5.34 300 25.0 (0.17) 208 (539) 7/28/83 0356 5.48 216 27.0 (0.16) 2/28/83 1405 2.30 576 28.0 12.0 (0.07) (31.1) 7/29/83 1305 5.20 500 28.0 (0.15) 50060000 Rio Grande de Loiza above Carolina. PR Lat 18 22 10, long 65 57 50 Hydrologic unit 21010005. 0.5 mi (0.8 km) west of Tru- 230 jillo Bajo and 0.2 mi (0.3 (596) km) northwest of intersection of Hwys 853 and 858. 2/28/83 1300 - 373 30.5 7/29/83 - Too High Lat 13 22 11, long 65 57 28 Hydrologic unit 21010005. At bridge on Hwy 853 and 0.3 mi (0.5 km) above junc- tion with Rio Grande de Loi- za. 50061000 Rio Grande de Loiza at Lat 18 22 39. long 65 57 08 Carolina. PR Hydrologic unit 21010005. 243 At bridge on Hwy 3. 0.5 (629) mi (0.8 km) southeast of Ca- rolina Plaza, and 9.1 mi (14.6 km) upstream from mouth. 50060200 Quebrada Maracuta at Trujillo 8ajo, PR 2/28/83 1240 1.93 555 30.0 10.2 (0.05) (26.4) 7/29/83 1105 2.60 590 23.0 (0.07) 2/28/83 1245 - 400 30.5 7/23/83 No meas Too High 50061200 Rio Canovanillas at Carruzos. PR Lat 13 19 03. long 65 54 16 Hydrologic unit 21010005. At bridge on road 500 ft (152 m) off Hwy 185. and 0.7 mi (1.1 km) east of Jesus T. Pinero School. 3/01/83 1255 2.58 556 29.5 9.10 (0.07) (23.57) 7/28/83 1245 2.18 510 30.0 (0.06) 50061500 Rio Canovanillas at Loiza. PR Lat 18 22 44. long 65 55 00 Hydrologic unit 21010005.At bridge on Hwy 3, 0.9 mi (1.4 16.5 km) upstream from Rio Gran- (42.7) de Loiza. and 1.0 mi (1.6 km) west of Loiza. 3/01/83 1005 4.39 589 26.5 (0.12) 7/28/83 0905 4.48 535 29.0 (0.13) 50061900 Rio Canovanas at La Marina. PR Lat 13 21 01. long 65 53 51 Hydrologic unit 21010005. 100 ft (30 m) east of Hwy 135 and 0.9 mi (1.5 km) downstream from bridge on Hay 957. 3/01/83 1435 9.36 237 29.5 (0.27) 7/28/83 1405 12.3 250 30.0 (0.35) 14.6 (37.8) 50062000 Rio Canovanas at Loiza. Lat 18 22 53. long 65 53 33 PR Hydrologic unit 21010005.At bridge on Hwy 958 and 0.3 mi (0.5 km) east of Loiza. Rio Herrera basin 3/01/83 1115 2.26 298 27.0 17.0 (0.06) (44.0) 7/28/83 1035 6.19 246 29.0 (0.18) 50062500 Rio Herrera near Colonia Lat 18 21 02. long 65 52 00 Dolores. PR Hydrologc unit 21010005. On right bank, at bridge on on Hwy 953. 2.0 mi (3.2 km) south of Colonia Dolores. and 3.2 mi (5.1 km) south- west of Rio Grande. 50062800 Rio Herrera near Loiza. Lat 18 22 43. long 65 51 33 PR Hydrologic unit 21010005. At bridge on Hwy 3. 1.9 mi (3.1 km) west of Rio Gran- de. and 2.8 mi (4.5 km) east of Loiza. 3/02/83 1235 2.58 225 25.0 (0.07) 2.75 (7.12) 7/27/83 1445 3.77 217 23.0 (0.11) 3/02/83 1120 2.88 270 26.5 3.86 (0.08) (10.00) 7/27/83 1125 3.99 257 29.0 (0.11) 50063000 Quebrada Cambalache near Loiza, PR Lat 18 22 49, long 65 52 04 Hydrologic unit 21010005.At bridge on Hwy 3. 2.2 mi (3.5 km) east of Loiza, and 2.5 mi (4.0 km) west of Rio Grande. 3/02/83 1015 0.16 711 26.0 1.32 (0.004) (3.42) 7/27/83 1300 0.36 540 23.5 (0.01) DISCHARGE AT PARTIAL RECORD STATIONS Low-flow partial-record stations--Continued 199 STATION STATION LOCATION DRAINAGE 3 SP TEMPER- AREA cu ft/s NUMBER NAME AND sq mi DATE TIME COND ATURE (cu BASIN (sq km) m/s) umhos deg C Rio Espiritu Santo basin 50063540 Rio Espiritu Santo at Lat 18 20 22, long 65 49 42 3/03/83 1030 4.47 73 23.0 Camp Eliza Colberg, PR Hydrologic unit 21010005. 5.27 (0.14) 3.1 mi (4.9 km) northwest of (13.65) Pico El Yunque and 0.8 mi 7/26/83 No Maas Gate Closed (1.3 km) below junction with Quebrada Sonadora. 50063850 Quebrada Jimenez near Let 13 2136, long 65 48 47 3/04/83 1100 2.03 173 31.5 Rio Grande, PR Hydrologic unit 21010005. 3.63 (0.06) 300 ft (91 m) upstream from (9.40) Rio Espiritu Santo and 1.9 7/26/83 0950 6.85 126 26.5 mi (3.1 km) southeast of Rio (0.19) Grande. 50064200 Rio Grande near El Verde, Lat 18 20 43, long 65 50 30 PR Hydrologic unit 21010005.On left bank, 400 ft (120 m) 3/02/83 1500 5.57 28.5 upstream from bridge on Hwy 7.31 (0.16) 960, 500 ft (150 m) south- (13.93) west of junction of Hays 956 & 960, 1.1 mi (1.8 km) 7/27/83 0905 12.7 131 26.0 west of El Verde, and 2.7mi (0.36) (4.3km) south of Rio Grande. 50064500 Rio Grande at Rio Grande, Let 13 22 40, long 65 49 28 PR Hydrologic unit 21010005.At bridge on Hwy 3, 0.5 mi (0.8 km) southeast of Rio Grande, and 0.8 mi (1.3km) upstream from Rio Espiritu Santo. 50064900 Quebrada Juan Gonzalez Let 13 22 37, long 65 48 04 near Rio Grande, PR Hydrologic unit 21010005.At bridge on Hwy 955, 300 ft (244 m) upstream from bridge on Hwy 3, and 1.5 mi (2.4 km) above junction with Rio Es- pirutu Santo. Rio Mameyes basin 50065500 Rio Mameyes near Sabana, Lat 13 19 46, long 65 45 04 PR Hydrologic unit 21010005. On left bank, at bridge on Hwy 938, 1.4 mi (2.3 km) west of Sabana, 2.0 mi (3.2 km) downstream from Rio de la Mina, and 3.2 mi (5.1km) southwest of Mameyes. 50066000 Rio Mameyes at Mameyes. Lat 18 22 30, long 65 45 50 PR hydrologic unit 21010005. At bridge on Hwy 3, 0.5 mi (0.8 km) downstream from Quebrada Anon, 0.5 mi (0.8 km) east of Mameyes (Palmer Post Office), and 3.1 mi (5.0 km) west of Luquillo. 3/02/83 1355 2.53 27.5 10.4 (0.07) (26.9) 7/27/83 1010 5.72 185 28.0 (0.16) 3/03/83 1245 0.97 304 31.0 2.17 (0.03) (5.62) 7/26/83 1115 3.54 260 26.0 (0.10) 3/03/83 1505 9.60 98 31.5 6.83 (0.27) (17.32) 7/26/83 1310 21.2 104 27.0 (0.60) 3/03/83 1345 5.74 148 31.0 13.5 (0.16) (35.0) 7/26/83 1350 31.6 150 29.0 (0.89) Quebrada Mata de Platano basin 50069000 Rio Pitahaya near Luquillo, PR 50069300 Tributary to Rio Juan Martin at Hwy 3, PR 50069350 Rio Juan Martin above mouth, PR Let 13 21 32, long 65 42 03 Hydrologic unit 21010005.At bridge on Hwy 3, 1.6 mi (2.6 km) southeast of Luquillo, and 1.7 mi (2.7 km) upstream from Rio Sabana. Rio Juan Martin basin Lat 13 21 14, long 65 40 59 Hydrologic unit 21010005.At bridge on Hwy 3 and 200 ft (61 m) above junction with Rio Juan Martin. Lat 18 21 44, long 65 40 35 Hydrologic unit 21010005. 0.8 mi (1.2 km) downstream from bridge on Hwy 3 and 0.4 mi (0.7 km) above mouth. 2.38 2/28/83 0945 0 30200 26.5 (6.16) 7/25/83 1100 0 2720 29.5 2/28/83 1110 4.34 645 27.0 7.05 (0.12) (18.26) 7/25/83 1220 15.0 153 23.0 (0.42) 2/28/83 1200 4.36 182 27.5 4.51 (0.12) (11.68) 7/25/83 1325 8.91 160 31.3 (0.25) 2/28/83 DRY 0.53 (1.37) 7/25/83 DRY 2/28/83 1430 3.60 460 30.0 2.41 (0.02) (6.24) 7/26/83 1022 1.14 352 30.0 (0.03) 50066500 Quebrada Mata de Platano Lat 13 22 52, long 65 43 16 near Luquillo, PR Hydrologic unit 21010005. At bridge on Hwy 3, 0.4 mi (0.6 km) northwest of Lu- quillo Plaza, and 0.3 mi (0.5 km) above mouth. Rio Sabana basin 50068000 Rio Sabana at Luquillo, Lat 18 22 15, long 65 42 51 PR Hydrologic unit 21010005.41 Hwy 3 bridge and 0.4 mi (0.6 am) southwest of Luquillo. Rio Pitahaya basin 3/02/83 4.29 (11.11) 7/27/83 No 540 28.0 Flow Ponded DISCHARGE AT PARTIAL RECORD STATIONS 200 STATION NUMBER STATION NAME Low-flow partial-record stations--Continued LOCATION DRAINAGE Q SP TEMPER- AREA cu ft/s AND sq mi DATE TIME COND ATURE (Cu BASIN (sq km) m/s) umhos deg C Rio Juan Martin basin 50069400 Quebrada Fajardo at Hwy Lat 13 20 49, long 65 39 55 194, PR Hydrologic unit 21010005. At bridge on Hwy 194, 0.5 mi (0.3 km) east of Hwy 194 and Hwy 3 intersection, and 1.5 mi (2.4 km) above mouth. Rio Fajardo basin 3/01/83 0948 0.12 585 27.0 1.16 (0.003) (3.00) 7/26/83 1122 0.44 548 30.5 (0.01) 50071200 Rio Fajardo at Vapor below Confluence. PR Let 13 18 28, long 65 40 10 Hydrologic unit 21010005. 19.4 1.7 mi (2.8 km) southwest of (50.2) Plaza de Fajardo and 1.4 mi (2.3 km) upstream from bridge on Hwy 3. 3/02/83 0805 7.65 152 25.5 (0.22) 7/26/83 No Meas Access Road Closed 50072000 Rio Fajardo at Fajardo. Lat 18 19 11. long 65 39 07 3/01/83 1238 11.6 158 29.5 PR Hydrologic unit 21010005. (0.33) At bridge on Hwy 3, 0.5 mi 21.6 (0.3 km) south of Fajardo, (55.9) and 2.5 mi (4.0 km) upstream 7/26/83 1337 34.9 152 33.0 from mouth. (0.99) 50072600 Quebrada Meta Redonda Lat 13 19 34, long 65 39 00 near Fajardo, PR Hydrologic unit 21010005.4t bridge on Hwy 3. 1.2 mi (2.0 3/02/83 DRY km) south of Plaza de Fa- 1.34 jardo, and 1.7 mi (2.7 km) (3.47) above junction with Rio Fa- 7/26/83 1015 0.10 460 31.5 jardo. (0.002) Rio Demajagua basin 50072700 Rio Demajagua at Demajagua. PR Lat 13 17 10, long 65 33 21 Hydrologic unit 21010005. At bridge on Hwy 3, 200 ft (61 m) south of Hwy 3 and Hwy 982 intersection, and 0.3 mi (0.5 km) above mouth. 3/02/83 0912 0.39 323 25.0 1.61 (0.01) (4.17) 7/27/83 1055 0.55 305 27.0 (0.02) Quebrada Ceiba basin 50072800 Quebrada Ceiba at Ceiba, Lat 13 16 25, long 65 38 25 PR Hydrologic unit 21010005.At bridge on Hwy 3, 0.8 mi (1.3 km) northeast of Plaza de Ceiba, and 0.8 mi (1.3 km) above mouth. Quebrada Aguas Claras basin 50072900 Quebrada Aguas Claras Lat 13 16 03, long 65 38 20 near Ceiba, PR Hydrologic unit 21010005.At bridge on Hwy 979 and 0.6 mi (0.9 km) above mouth. Rio Daguao basin 50073200 Rio Daguao at Daguao, PR Lat 13 13 42, long 65 40 39 Hydrologic unit 21010005. At railroad bridge, 0.1 mi (0.2 km) downstream from bridge on Hwy 3, 0.3 mi (0.5 km) east of Daguao. and 2.8 mi (4.5 km) upstream from mouth. 50073300 Rio Daguao above mouth. Lat 13 13 36, long 65 39 31 PR Hydrologic unit 21010005. At bridge 650 ft (200 m) downstream from bridge on Langley Drive and 0.9 mi (1.4 km) above mouth. 3/02/83 1347 1.01 520 32.0 2.15 (0.03) (5.57) 7/27/83 1135 1.69 548 33.0 (0.05) 3/02/83 0942 0.64 490 26.0 0.83 (0.02) (2.15) 7/27/83 1211 0.76 550 31.0 (0.02) 3/02/83 1125 0.59 355 29.0 2.26 (0.02) (5.85) 7/27/83 1342 1.67 413 30.5 (0.05) Quebrada Palma basin 50073400 Quebrada Palma at Daguao. Lat 18 13 16, long 65 41 30 PR hydrologic unit 21010005. At bridge on Hwy 3, 0.8 mi (1.3 km) southwest of Da- guao, and 1.7 mi (2.7 km) upstream from mouth. 4.84 (12.54) 3/02/83 1230 1.47 350 28.0 (0.04) 7/28/83 1302 3.08 285 28.5 (0.09) Quebrada Botija basin 50073500 Quebrada Botija at Hwy. Lat 18 12 55, long 65 42 25 31, PR Hydrologic unit 21010005. At bridge on Hwy 31, 500 ft (152 m) upstream from bridge on Hwy 3, and 1.6 mi (2.6 km) above mouth. 3/02/33 1255 0.08 379 28.5 1.10 (0.002) (2.85) 7/28/83 1340 0.43 420 29.0 (0.01) DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations--Continued 201 STATION STATION LOCATION DRAINAGE Q SP TEMPER- AREA cu ft/s NUMBER NAME AND sq mi DATE TIME COND ATURE (cu BASIN (sq km) m/s) umhos deg C Rio Santiago basin 50074000 Rio Santiago at Naguabo, Lat 18 12 57, long 65 43 41 PR Hydrologic unit 21010005.At 3/03/83 0915 1.72 215 26.5 bridge on Hwy 31, 0.3 mi 4.99 (0.05) (0.5 km) northeast of Nagua- (12.92) bo, 0.4 mi (0.6 km) downstream 7/28/83 1431 4.56 165 31.0 from Quebrada Grande, and (0.13) 2.2 mi (3.5 km) upstream from mouth. 50074010 Tributary to Rio Let 18 12 04, long 65 43 33 Santiago at Hwy 192, PR Hydrologic unit 21010005. 3/03/83 0930 No 396 26.0 At bridge on Hwy 192 and 1.08 0.7 mi (1.1 km) above junc- (2.80) 7/28/83 1520 Flow 412 29.5 tion with Rio Santiago. Rio Blanco basin 50077000 Rio Blanco at Rio Blanco, Lat 18 13 09, long 65 46 57 2/28/83 1050 2.75 - 28.5 PR Hydrologic unit 21010005. At (0.08) bridge on Hwy 31 and 0.4 mi 17.6 (0.6 km) east of Rio Blanco. (45.6) 7/25/83 1335 35.0 121 29.0 (0.99) 50077500 Rio Blanco below La Fe, Lat 18 12 17, long 55 45 31 2/28/83 1215 7.79 - 27.0 PR Hydrologic unit 21010005. 20.8 (0.22) 1.9 mi (3.0 km) downstream (53.9) from bridge on Hwy 31 and 7/26/83 1035 32.0 171 27.5 0.7 mi (1.1 km) south of (0.91) Hwy 31 and Hwy 970 intersec- tion. 50077600 Quebrada Vaca below La Lat 18 12 25, long 65 45 04 Fe, PR Hydrologic unit 21010005. 2/28/83 1315 0.85 29.0 1.1 mi (1.8 km) downstream 3.47 (0.02) from bridge on Hwy 31 and (8.99) 0.8 mi (1.4 km) southeast of 7/26/83 0945 3.48 273 29.5 Hwy 31 and Hwy 970 intersec- (0.10) tion. 50077700 Rio Blanco at mouth, PR Lat 13 11 17, long 65 43 47 Too Hydrologic unit 21010005.At 2/28/83 0945 Deep 23000 28.0 bridge on Hwy 3, at mouth, 27.2 and 0.8 mi (1.2 km) south- (70.4) west of Hwy 3 and Hwy 192 7/28/83 1421 69.6 2850 30.0 intersection. (1.97) Rio Anton Ruiz basin 50078510 Rio Anton Ruiz at Pasto Let 18 10 26, long 65 47 05 2/28/83 1500 1.90 28.0 Viejo, PR Hydrologic unit 21010005.At 5.75 (0.05) bridge on unimproved road, (14.89) 300 ft (91 m) north of Hwy 7/26/83 1215 2.99 344 31.5 925, and 1.5 mi (2.4 km) (0.08) north of Hwy 3 and Hwy 925 intersection. 50078700 Rio Anton Ruiz at mouth, Lat 18 10 35, long 65 44 23 PR Hydrologic unit 21010005. At bridge on Hwy 3, 1.8 mi (2.9 km) southwest of Hwy 3 and Hwy 192 intersection, and 200 ft (61 m) above mouth. Rio Humacao basin. 2/28/83 0945 Ponded 23400 28.0 a 7.99 (20.69) 7/28/83 1645 Ponded 17500 30.0 50081000 Rio Humacao at Las Piedras, PR Let 18 10 27, long 65 52 11 Hydrologic unit 21010005. On left bank about 60ft (18.3 m) off bridge on Hwy 921 6.65 (km 1.1), 0.6mi (1.0km) south- (17.22) east of junction with Hwy 30, 0.8 mi (1.3 km) down- stream from Quebrada Blanca, and 0.8mi (1.3km) south of Las Piedras. 3/01/83 1325 9.38 27.0 (0.27) 7/26/83 1505 15.9 164 29.5 (0.54) 50081500 Rio Humacao near Humacao, Let 18 09 37, long 65 50 41 PR Hydrologic unit 21010005.At bridge on Hwy 914 and 1.3 mi (2.1 km) northwest of Humacao. 50081900 Quebrada Mariana at Patagonia, PR 50082500 Rio Humacao Flood Channel near mouth, PR Lat 18 08 46, long 65 49 40 Hydrologic unit 21010005.At bridge on Hwy 908 and 450 ft (137 m) above junction with Rio Humacao. Lai 18 07 28, long 65 47 23 Hydrologic unit 21010005. 3.1 mi (4.9 km) southeast of Plaza de Humacao and 0.6 mi (0.9 km) above mouth. 3/01/83 1230 7.23 - 25.0 9.23 (0.20) (23.91) 7/26/83 1420 15.3 197 31.0 (0.43) 3/01/83 1110 5.63 - 29.0 5.76 (0.16) (14.92) 7/26/83 1310 10.8 252 31.0 (0.31) 3/01/83 0950 23.7 353 27.5 25.1 (0.67) (65.0) 7/28/83 1220 37.0 375 32.0 (1.05) 202 STATION NUMBER Q SP cu ft/s CONED (cu m/s) umhos TEMPER- ATURE deg C DRAINAGE AREA sq mi DATE TIME (sq km) STATION NAME LOCATION AND BASIN Rio Candelero basin Low-flow partial-record stations--Continued 4.77 (1 2.35) 3/02/83 1030 0.05 - 29.5 (0.001) 7/28/83 1035 2.01 301 32.0 (0.06) 4.69 (12.15) 50082800 Rio Guayanes near Colonia Laura, PR Rio Guayanes basin Lat 13 04 55, long 65 57 32 Hydrologic unit 21010005.On left bank, 1000 ft (305 m) south of Hwy 182, 4.5 mi (7.2km) west of Colonia Laura, and 5.8 mi (9.3 km) north- northwest of Yabucoa. 3/02/83 0835 7.96 150 23.5 (0.23) 7/28/83 1047 16.6 140 26.0 (0.47) 50083400 Rio Guayanes at Calabazas, PR Let 18 03 33, long 65 54 03 Hydrologic unit 21010005.At bridge on Hwy 132 and 1.4 mi (2.2 km) above junction with Rio Limones. 125 25.0 3/01/83 1350 31.6 26.5 (0.89) (68.6) 7/28/83 1507 3/03/83 1030 28.2 26.6 (0.80) ( 68.9) 7/27/83 0950 70.7 165 26.5 (71.5) 3/02/83 1410 30.9 - 29.0 27.6 (0.87) 7/27/83 1250 63.3 157 29.0 6.37) ( (1.93) 3/03/83 1325 2.03 - 23.0 2.46 (0.06) 7/27/83 1135 6.83 194 29.5 (0.19) (29.8) 3/02/83 1305 4.66 - 30.0 11.5 (0.13) 7/28/83 0925 11.1 270 28.5 (0.31) (38.1) 3/02/83 1210 36.4 34.0 (1.03) 7/27/83 1350 88.2 (2.50) DISCHARGE AT PARTIAL-RECORD STATIONS 50082600 Rio Candelero at Hwy 906, Lat 18 06 17, long 65 48 54 PR Hydrologic unit 21010005.At bridge on Hwy 906, 1.4 mi (2.2 km) downstream from bridge on Hwy 3, and 1.7 mi (2.7 km) above mouth. 50082700 Rio Candelero at mouth, Lat 18 06 09, long 65 47 43 PR Hydrologic unit 21010005.At bridge on unimproved road, 1.3 mi (2.1 km) downstream from bridge on Hwy 906, and 0.4 mi (0.7 km) above mouth. 50082810 Rio Guayanes below Rio Lat 18 04 44, long 65 56 54 Arenas, PR Hydrologic unit 21010005. 100 ft (30 m) below junction with Rio Arenas and 2.8 mi (4.6 km) above junction with Quebrada Guayabo. 50084000 Rio Limones near Yabucoa, Lat 18 04 35, long 65 53 42 PR Hydrologic unit 21010005.At bridge on Hwy 904, 1.2 mi (2.0 km) upstream from Rio Guayanes, and 2.0 mi (3.2 km) northwest of Yabucoa. 50085000 Rio Guayanes at Yabucoa, Let 18 03 42, long 65 52 33 PR Hydrologic unit 21010005.At bridge on Hwy 3, 0.5 mi(0.8 km) downstream from Rio Li- mones, and 0.7 mi (1.1 km) north of Yabucoa. 50085100 Rio Guayanes at Central Lat 18 03 57, long 65 52 22 Roig, PR Hydrologic unit 21010005. At abandonend lake control structure, 0.2 mi (0.3 km) northeast of Central Roig, 1.0 mi (1.6 km) downstream from Rio Limones, and 1.0 mi (1.6 km) northeast of Yabucoa. Let 18 04 16, long 65 50 14 Hydrologic unit 21010005. At dirt road crossing, south of Hwy 906, and 3.1 mi (5.0 km) northeast of Yabucoa. Lat 18 05 03, long 65 51 27 Hydrologic unit 21010005.At bridge on Hwy 3, 0.2 mi (0.3 km) upstream from Quebrada Cortadera and Aguacate, and 2.6 mi (4.2 km) northeast of Yabucoa. Let 13 04 20, long 65 50 02 Hydrologic unit 21010005. 1.8 mi (2.9 km) downstream from bridge on Hwy 3 and 0.6 mi (1.0 km) above junc- tion with Rio Guayanes. 50086500 Rio Guayanes at Playa de Lat 18 03 45, long 65 49 42 Guayanes, PR Hydrologic unit 21010005. At old railroad crossing, 0.2 mi (0.3 km) from mouth, 0.4 mi (0.6km) west of Pla- ya de Guayanes, and 3.5 mi (5.6 km) northeast of Yabu- coa. 3/02/83 0950 0.61 - 27.0 3.65 (0.02) 7/28/83 1115 1.97 294 30.5 (0.06) 9.45) ( 7.44 (19.27) 17.2 (44.5) 7.89 (1 2.70) 7/28/83 No 3/01/83 1045 7/28/83 1342 3/01/83 1505 7/28/83 0932 Maas Made 23.8 165 25.0 (0.67) 46.5 158 27.0 (1.32) 11.2 169 27.0 (0.32) 21.0 166 26.0 (0.59) 3/01/83 0925 9.17 147 23.5 (0.26) (2.00) 73.1 160 28.5 (2.07) 23.0 50085700 Rio Guayanes near mouth near Playa de Guayanes, PR 50086000 Rio del Ingenio near Yabucoa, PR 50086300 Rio del Ingenio near Playa de Guayanes, PR 166 28.5 155 30.0 DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations--Continued 203 STATION STATION LOCATION DRAINAGE Q SP TEMPER- AREA cu ft/s NUMBER NAME AND sq mi DATE TIME COND ATURE (cu BASIN (sq km) m/s) umhos deg C Cano Santiago basin 50087100 Cano Santiago at Hwy 3. Lat 18 03 25, long 65 52 33 PR Hydrologic unit 21010005.At 3.81 bridge on Hwy 3, 0.5 mi (0.8 (9.87) km) north of Plaza do Yabucoa, and 0.3 mi (0.5 km) below junc- tion with Quebrada Aguas Largas. 3/01/83 1205 1.92 323 26.0 (0.05) 7/28/83 1602 3.60 268 28.0 (0.10) 6.04 (15.64) 50087200 Cano Santiago near Central Roig, PR Let 13 03 13, long 65 50 59 Hydrologic unit 21010005. At service road and railroad bridge, 1.8 mi (2.9 km) east of Central Roig. and 2.0 mi (3.2 km) east of Yabucoa. Rio Jacaboa basin 3/03/83 1205 4.27 27.5 (0.12) 7/28/83 1045 7.19 360 29.0 (0.20) 3/02/83 1000 8.14 250 26.5 (0.23) 7/28/83 1732 19.8 218 28.5 (0.56) 12.4 (32.1) Rio Maunabo bastn 50091000 Rio Maunabo at Maunabo. Lat 18 00 24, long 65 54 19 PR Hydrologic unit 21010005. At bridge on Hwy 3, 0.4 mi (0.6 km) southwest of Mau- nabo, and 1.3 mi (2.1 km) upstream from mouth. 50091500 Rio Jacaboa at Hacienda Let 17 58 48, long 65 58 03 San Isidro, PR Hydrologic unit 21010004. At bridge on Hwy 3, 0.4 mi (0.6km) upstream from mouth, 0.4 mi (0.6 km) east of Ha- cienda San Isidro, and 4.8 mi (7.7 km) southwest of Maunabo. Rio Chico basin 3/02/83 1115 0.39 330 28.5 5.23 (0.01) (13.5) 7/27/83 0915 3.79 263 27.0 (0.11) 50091800 Rio Chico at Providencia, Lat 17 59 16. long 66 00 18 PR Hydrologic unit 21010004. At flat low bridge 200 ft (61 m) south of Hwy 3. 0.5 mi (0.8 km) above mouth, and 1.5 mi (2.4 km) south- east of Patillas. 50094200 Rio Grande de Patillas Let 18 00 15. long 66 01 27 at Patillas, PR Hydrologic unit 21010004. At bridge on Hwy 3. 0.7 mi (1.1 km) west of Patillas, and 1.9 mi (3.1km) upstream from mouth. 50094500 Rio Nigua at Arroyo. PR Let 17 58 10. long 66 03 41 Hydrologic unit 21010004. At bridge on Hwy 178, 0.2 mi (0.3 km)north of Arroyo. and 3.7 mi (6.0 km) east of Guayama. Quebrada Salada basin 3/02/83 1225 0.64 1200 30.5 (0.02) 4.93 (12.77) 7/27/83 1010 0.34 660 27.0 (0.01) 3/03/83 1340 9.47 140 26.0 (0.27) 7/27/83 1415 28.6 138 27.0 (0.82) 3/02/83 1410 0.22 552 33.5 (0.01) 27.9 (72.3) 7/27/83 1515 25.0 165 32.0 (0.71) 3/03/83 0910 0.39 315 26.0 (0.03) 7/27/83 1142 23.6 176 30.0 (0.81) 3/03/83 1015 0.10 900 28.0 (0.003) 8.04 (20.82) 7/27/83 1620 0.80 610 31.5 (0.02) Rio Grande de Patillas basin 50091950 Rio Grande de Patillas Lat 18 03 48, long 66 02 57 below Quebrada Sonadora, Hydrologic unit 21010004. 8.75 PR 1.300 ft (395 m) downstream (22.66) from bridge on Hwy 134 and 1.000 ft (305 m) below junc- tion with Quebrada Sonadora. 50094300 Rio Grande de Patillas Lat 17 59 20, long 66 00 47 at Providencia, PR Hydrologic unit 21010004. At abandoned railroad bridge, 29.0 0.5 mi (0.8 km) above mouth, (75.1) and 0.6 mi (1.0 km) west of Providencia. Rio Nigua basin 50094510 Quebrada Salada near Arroyo, PR Lat 13 58 50, long 66 04 23 Hydrologic unit 21010004. At bridge on Hwy 3 and 0.9 mi (1.4 km) upstream from mouth. Quebrada Corazon basin 0.76 (1.97) 3/03/83 1105 0.03 220 27.5 (0.001) 7/27/83 1700 0.09 2200 30.0 (0.003) 50094520 Quebrada Corazon near Lat 18 58 58, long 66 04 41 Arroyo, PR Hydrologic unit 21010004.4t bridge on Hwy 3 and 1.0 mi (1.6 km) above mouth. 4.29 (11.11) 3/03/83 1155 0.08 850 27.0 (0.002) 7/29/83 1332 3.08 590 27.0 (0.09) DISCHARGE AT PARTIAL-RECORD STATIONS 204 Low-flow partial-record stations--Continued STATION STATION LOCATION DRAINAGE C) SP TEMPER- AREA cu ft/s NUMBER NAME AND sq mi DATE TIME COND ATURE (cu BASIN (sq km) m/s) umhos deg C Rio Guamani basin 50095500 Rio Guamani near Guayama, Lat 17 57 30, long 66 08 20 PR Hydrologic unit 21010004. At railroad bridge, 0.5 mi 12.3 3/07/83 1150 1.67 395 28.0 (0.3 km) downstream from (31.9) (0.05) Hwy 3, 1.2 mi (1.9 km) up- stream from mouth, and 2.5 mi (4.0 km) southwest of Guayama. Rio Melania basin 50095900 Rio Malania near Jobos, Lat 17 57 51, long 66 59 30 PR Hydrologic unit 21010004. 3.51 3/07/83 1215 0.02 550 28.0 0.6 mi (1.0 km) upstream (9.09) (0.001) from bridge on Hwy 3. Rio Seco basin 50097800 Rio Seco near Central Lat 17 58 06, long 66 10 52 Guamani, PR Hydrologic unit 21010004.At bridge on Hwy 3, 0.2 mi 11.1 3/07/83 1300 1.11 490 30.0 (0.3 km) north of Central (28.7) (0.03) Guamani, and 1.2 mi (1.9 km) northwest of Jobos. Rio Salinas (Nigua) basin 50100700 Rio Majada at Rabo del Lat 19 02 17, long 66 14 27 Buey, PR Hydrologic unit 21010004.At 22.2 3/07/83 1025 0.27 660 24.5 bridge on Hwy 1, at Rabo del (57.5) (0.01) Buey, 200 ft (61 m) upstream from Rio Lapa, and 5.6 mi (9.0 km) northeast of Sali- nas. 50102000 Rio Salinas at Salinas, Let 17 58 42, long 66 13 17 PR Hydrologic unit 21010004.At bridge on Hwy 1 and 0.4 mi (0.6 km) west of Salinas 52.4 3/07/83 DRY Plaza. (135.7) Rio Jueyes basin 50103000 Rio Jueyes near Jauca, PR Lat 17 58 45, long 66 20 20 Hydrologic unit 21010004.At bridge on Hwy 1, 1.8 mi (2.9 8.56 3/07/83 DRY km) east of Jauca, and 2.7 (22.17) mi (4.3 km) west of Salinas Plaza. Rio Coamo basin 50107000 Rio Coamo near Santa Isabel, PR Lat 17 58 36, long 66 25 10 Hydrologic unit 21010004.At bridge on Hwy 1, at Velaz- 69.0 3/07/83 DRY quez, and 1.1 mi (1.8 km) (178.7) northwest of Santa Isabel Plaza. Rio Descalabrado basin 5010350C Rio Descalabrado near Lat 17 59 34, long 66 26 35 Santa Isabel, PR Hydrologic unit 21010004.At bridge on Hwy 1, 0.9 mi (1.4 18.1 3/07/83 1125 0.15 856 27.5 km) upstream from mouth, and (46.9) (0.004) 3.1 mi (5.0 km) northwest of Santa Isabel. Rio Canas basin 50109500 Rio Canas near Santa Isabel, PR Lat 17 59 39, long 66 28 35 Hydrologic unit 21010004.At bridge on Hwy 1, 0.5 mi (0.8 6.38 3/07/83 DRY km) from mouth, 0.6 mi (1.0 (16.52) km) east of Pastillo, and 5.1 mi (8.2 km) northwest of Santa Isabel Plaza. Rio Jacaguas basin 50112000 Rio Jacaguas at Arus, PR Let 13 00 05, long 66 31 50 Hydrologic unit 21010004.At bridge on Hwy 1, at Arus, and 59.3 3/07/83 DRY 4.0 mi (6.4 km) south of (153.6) Juana Diaz. Rio Inabon basin 50113450 Rio Inabon near Arus, PR Lat 18 00 22, long 66 33 13 Hydrologic unit 21010004. At bridge on Hwy 1, 0.9 mi 30.2 (1.4 km) east of Ponce Mu- (78.2) nicipal Airport terminal, and 1.7 mi (2.7 km) west of Arus. 3/08/83 0945 0.06 1443 27.0 (0.002) DISCHARGE AT PARTIAL-RECORD STATIONS 205 Low-flow partial-record stations--Continued STATION STATION LOCATION DRAINAGE 0 SP TEMPER- AREA cu ft/s NUMBER NAME AND sq mi DATE TIME COND ATURE (cu BASIN (sq km) m/s) umhos deg C Rio Bucana basin 50114600 Rio Bucana at Ponce, PR Lat 18 00 28, long 66 35 36 Hydrologic unit 21010004. At bridge on Hwy 1, 0.2mi (0.3 27.3 3/08/83 1115 5.72 343 26.0 km) east of intersection of (70.7) (0.16) Hays 1 and 2, 1.5mi (2.4km) east of Plaza Degetau in Ponce, and 3.1mi (5.0km) upstream from mouth. Rio Portugues basin 50116500 Rio Portugues at Hwy 2 Lat 17 59 52, long 66 36 52 by-pass at Ponce, PR Hydrologic unit 21010004. On pier at bridge on Hwy 2 bypass, 1.1 mi (1.3 km) 20.5 3/08/83 1215 3.67 546 30.0 south of Plaza Degetau, and (53.1) (0.10) 2.0 mi (3.2 km) upstream from mouth. Rio Matilde basin 50122000 Lat 13 00 37, long 66 38 23 hydrologic unit 21010004. 0.5 mi (0.8 km) upstream from junction with Rio Pas- tillo. Lat 17 59 13, long 66 38 22 Hydrologic unit 21010004. 700 ft (213 m) upstream from junction with Rio Matilde. Rio Tallaboa basin Rio Tallaboa at Tallaboa, Lat 18 00 31, long 66 43 49 PR Hydrologic unit 21010004.At bridge at Hacienda Dolores, 700 ft (213 m) upstream from Hwy 2, 0.3 mi (1.3 km) north- west of Tallaboa, and 7.6 mi (12.2 km) west of Plaza C4" getau in Ponce. Rio Macana basin 50116970 Rio Canas below Las Americas Avenue, PR 50119200 Quebrada del Agua at Playa de Ponce, PR 8.39 3/03/83 0820 10.7 (21.73) (0.30) 6.45 3/03/83 DRY (16.71) 31.50 3/03/83 DRY (81.6) 50122900 Rio Macana at Magas Arriba, PR Lat 13 01 00, long 66 45 57 Hydrologic unit 21010004. 8.96 DRY 3/02/83 1.8 mi (2.8 km) east of Pla- (23.21) za de Guayanilla, 200 ft (60 m) upstream from bridge on Hwy 2, and 0.6 mi (1.0 km) upstream from mouth. Rio Yauco basin 50126500 Rio Yauco at Pueblo Sur Lat 13 02 03, long 66 50 51 at Yauco, PR Hydrologic unit 21010004.At bridge on Hwy 2, 0.1 mi 33.0 3/02/83 DRY (0.2 km) east of Yauco, and (85.5) 0.6 mi (1.0 km) upstream from Guebrada Berrenchin. Rio Loco basin 50129200 Quebrada Susua at Palomas, PR Lat 15 01 19, long 66 52 28 Hydrologic unit 21010004.4t bridge on Hwy 2, 0.5 mi (0.3 3.23 3/02/83 DRY km) north of Palomas, and (8.3') 1.9 mi (3.1 km) southwest of Yauco. 50129500 Rio Loco near Guanica, PR Lat 17 59 33, long 66 54 59 Hydrologic unit 21010004. 90 ft (27 m) upstream from sheet piling drop structu- 21.0 3/02/83 DRY re, 900 ft (274 m) upstream (54.4) from Lajas Orainage Canal, 7.2 mi (11.6 km) downstream from Lago Loco, and 1.5 mi (2.4 km) north of Guanica. Quebrada Boqueron basin 50130000 Quebrada Boqueron at Lat 18 01 40, long 67 09 35 Boqueron, PR Hydrologic unit 21010004.At bridge on Hwy 101 and 0.9 4.35 3/02/83 Ponded mi (1.4 km) above mouth. (11.27) Rio Guanajibo basin 50132010 Rio Guanajibo below San Lat 13 05 28, long 67 02 38 German, PR Hydrologic unit 21010003. 0.5 mi (0.8 km) north of 36.1 3/02/83 1025 5.11 Plaza de San German and (93.5) (0.14) 1,500 ft (457 m) downstream from bridge on Hwy 360. Drainage Period area of sq mi record (sq km) Date Annual maximum Gage Dis- height charge ft cu ft/s (m) (cu m/s) 18.6 1963-83 < 8.82 < 1,700 (43.2) (<2.688) (<48.1) 206 DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations--Continued STATION STATION LOCATION DRAINAGE Q 5P TEMPER- AREA cu ft/s NUMBER NAME AND sq mi DATE TIME COND ATURE (cu BASIN (sq km) m/s) umhos deg C Rio Yaguez basin 50138900 Rio Yaguez at Balboa, PR Lat 18 12 13, long 67 07 55 Hydrologic unit 21010003. 1,200 ft (366 m) upstream from bridge on Balboa St. and 1.6 mi (2.6 km) up- stream from mouth. Rio Grande de Anasco basin 12.2 3/01/83 0820 3.80 (31.6) (0.11) 50146070 Rio Grande de Anasco at Lat 13 16 21, long 66 08 33 Anasco Arriba, PR Hydrologic unit 21010003. 0.8 mi (1.2 km) south of 176 3/01/83 1425 75.3 Anasco and 3.0 mi (4.8 km) (456) (2.13) upstream from mouth. Rio Grande basin 50146200 Rio Grande near Rincon, Lat 13 22 06, long 67 13 56 PR Hydrologic unit 21010003. At bridge on Hwy 115, 1.2 mi 2.83 2/28/83 1450 0.25 (1.9 km) upstream from mouth, (7.33) (0.01) and 2.2 mi (3.5 ks) northeast of Rincon. Rio Ingenio basin 50146400 Rio Ingenio near Aguada, Let 13 22 50, long 67 12 34 PR Hydrologic unit 21010003. At bridge on unimproved road, 0.3 mi (0.5 krn) upstream from confluence with Rio Culebra, 0.7 mi (1.1 km) upstream from mouth of Rio Guayabo, and 1.4 mi (2.3 km) west of Aguada. 6.22 (16.11) 3/01/83 0935 2.37 470 23.0 (0.07) Rio Culebra basin 50146600 Rio Culebra near Aguada, Lat 13 22 26, long 67 11 35 PR Hydrologic unit 21010003. At bridge on Hwy 411, 0.6 mi 3.70 2/28/83 1331 1.87 (1.0 km) south of Aguada, 1.5 (9.53) (0.05) mi (2.4 km) upstream from confluence with Rio Ingenio, and 1.9 mi (3.1 km) upstream from mouth of Rio Guayabo. Rio Culebrinas basin 50149100 Rio Culebrinas near Aguada, PR Lat 13 24 03, long 67 09 40 Hydrologic unit 21010003. At bridge on Hwy 2 and 2.3 mi (3.7 km) northeast of Aguada Plaza. 97.0 (251.2) 3/01/83 1210 15.6 310 28.0 (0.44) a Drainage area does not include coastal undefined drainage. DISCHARGE AT CREST-STAGE PARTIAL-RECORD STATIONS The following table contains annual maximum discharge for crest-stage stations. A crest-stage gage is a device which will register the peak stage occurring between inspections of the gage . A stage-discharge relation for each gage is developed from discharge measurements made by indirect measurements of peak flow or by current meter. The date of the maximum discharge is not always certain but is usually determined by comparison with nearby continuous- record stations, weather record, or local inquiry. Only the maximum discharge for each water year is given. Infor- mation on some lower floods may have been obtained, and discharge measurements may have been made for purposes of establishing the stage-discharge relation, but these are not published herein. The years given in the period of rec- ord represent years for which the annual maximum has been determined. Annual maximum discharge at crest-stage partial-record stations during water year 1983 Station number 50115900 Station name Location Rio Portugues basin Rio Portugues at Lat 18 01 09, long 66 36 26, Highway 14 at on left downstream side of Ponce, PR Highway 14 bridge, 1.7 mi (2.7 km) downstream from Rio Chiquito, and 0.6 mi (0.97 km) northeast of Degetau Plaza in Ponce. 207 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS Water-quality partial-record stations are particular sites where chemical-quality , biological, and or sediment data are collected systematically over a period of years for use in hydrologic analyses. The data are collected usually less than quarterly. WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, COLI- STREP- SOLIDS, SPE- DIS- FORM, TOCOCCI ALKA- RESIDUE NITRO- CIFIC SOLVED FECAL, FECAL. LINITY AT 105 GEN, SAM- CON- PH OXYGEN, (PER- 0.7 KF AGAR FIELD DEG. Co NITRATE FLING DUCT- (STAND- TEMPER- DIS- CENT UM-MF (COLS. (MG/L SUS- TOTAL TIME DEPTH ANCE ARD ATURE SCLVED SATUR- (COLS./ PER AS PENDED (MG/L DATE (FEET) (UMHOS) UNITS) (DEG C) (MG/L) ATION) 100 ML) 100 ML) CAC03) (MG/L) AS N) RIO GUAJATACA BASIN 50010720 - LAGO DE GUAJATACA NO.3 NEAR MOUTH NEAR QUEBRADILLAS,PR (LAT 18.22'05" LONG 066.54'36") DEC , 1982 09... 1510 1.00 260 8.2 26.0 7.8 99 K5 K5 130 5 FEB , 1983 23... 1340 1.00 316 7.7 25.5 8.7 109 K1 K2 150 4 .19 JUN 23... 1300 1.00 356 8.3 31.5 12.1 168 <1 K12 84 OXYGEN, COLI- STREP- SOLIDS, SPE- DIS- FORMr TOCOCCI RESIDUE HARD- CIFIC SOLVED FECAL, FECAL, AT 105 HARD- NESS, SAM- CON- PH OXYGEN, (PER- 0.7 KF AGAR DEG. C. NESS NONCAR- PLING DUCT- (STAND- TEMPER- DIS- CENT UM-MF (COLS. SUS- (MG/L BONATE TIME DEPTH ANCE ARD ATURE SOLVED SATUR- (COLS./ PER PENDED AS (MG/L DATE (FEET) (UMHOS) UNITS) (DEG C) CMG/L) ATION) 100 ML) 100 ML) (MG/L) CAC03) CAC03) 50010790 - LAGO DE GUAJATACA NO.1 NEAR DAM NEAR QUEBRADILLA S,PR (LAT 18'23'56" LONG 066°55'23") DEC , 1982 09... 1605 1.00 257 8.2 26.0 7.8 99 K31 K100 2 130 0 09... 1620 85.0 332 7.2 23.5 .0 0 -- 140 5 FEB , 1983 23... 1440 53.0 333 6.8 23.5 .0 0 -- 140 23... 1445 1.00 295 7.9 25.5 9.2 115 K6 <1 <1 140 10 JUN 23... 1220 1.00 261 7.9 30.5 8.2 112 K2 K12 4 120 0 23... 1225 82.0 383 6.7 24.5 .0 0 -- 180 2 RIO GRANDE DE ARECIBO BASIN 50020050 - LAGO GARZAS NO.1 NEAR DAM NEAR ADJUNTAS,PR (LAT 18°08'21" LONG 066°44'35") DEC , 1982 08... 1315 1.00 123 6.9 22.0 12.3 136 K6 <1 <1 50 0 08... 1325 74.0 164 6.8 21.0 .3 3 -- 51 0 FEB , 1983 22... 1335 1.00 144 7.6 21.5 7.6 94 K7 K5 <1 58 0 22... 1350 87.0 159 6.5 20.0 .0 0 -- -- 53 0 JUN 23... 0835 1.00 146 7.9 25.0 7.2 96 K12 K16 4 60 0 23... 0840 102 142 6.6 20.5 .0 0 -- -- 60 0 K = non-ideal count ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 208 N ITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- GEN, GEN, GEN, GEN, MONIA + NITRO- NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE AS N) AS N) AS N) AS N) AS N) AS N) NITRO- GEN, TOTAL (MG/L AS NO3) PHOS- PHORUS, TOTAL (MG/L AS P) BIOMASS CHLOR-A CHLOR-B PHYTO- CHLORO- PHYTO- PHYTO- PLANK- PHYLL PLANK- PLANK- TON, RATIO TON TON TOTAL PLANK- CHROMO CHROMO (CELLS TON FLUOROM FLUOROM PER ML) (UNITS) (UG/L) (UG/L) RIO GUAJATACA BASIN--CONTINUED 50010720 - LAGO DE GUAJATACA NO.3 NEAR MOUTH NEAR QUEBRADILLAS,PR (LAT 18°22'05" LONG 066°54'36") DEC , 1932 09... <.010 <.10 <.010 .40 .020 93000 .00 6.20 (.100 FEB p 1983 23... .010 .20 <.010 .80 1.0 4.4 .040 6700 .00 19.0 (.100 JUN 23... <.010 <.10 <.010 .60 .020 14000 .00 8.00 <.100 SOLIDS, MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, SUM OF NITRO- CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE, DIS- CONSTI- GEN, DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- SOLVED TUENTS, NITRATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L DIS- TOTAL (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS SOLVED (MG/L DATE AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) SI02) (MG/L) AS N) 50010790 - LAGO DE GUAJATACA NO.1 NEAR DAM NEAR QUEBRADILLAS,PR (LAT 18° 23'56" LONG 066°55'23") DEC , 1932 09... 40 6.1 11 .4 1.4 130 12 9.5 <.10 1.1 159 09... 49 3.1 4.5 .2 1.6 130 3.0 5.9 <.10 4.9 155 FEB , 1933 23... 50 3.8 6.0 .2 1.9 140 9.0 7.8 .10 3.0 166 -- 23... 50 3.8 5.0 .2 1.9 131 9.0 7.9 .10 3.0 160 .09 JUN 23... 42 3.5 5.7 .2 1.5 154 14 9.1 .20 3.5 172 23... 67 3.5 5.6 .2 1.5 180 12 9.6 .20 6.8 214 RIO GRANDE DE ARECIBO 3ASIN-CONTINUED 50020050 - LAGO GARZAS NO.1 NEAR DAM NEAR ADJUNTAS,PR (LAT 18°08'21" LONG 066°44'35") DEC , 1932 08... 14 3.7 5.3 .3 .9 51 3.0 4.6 <.10 16 78 03... 14 3.8 5.5 .3 1.0 52 3.0 4.6 <.10 16 79 FEB , 1933 22... 16 4.3 5.9 .4 1.3 61 <5.0 5.1 <.10 16 90 .09 22... 15 4.3 5.9 .4 1.3 62 <5.0 5.3 <.10 16 -- JUN 23... 17 4.3 6.2 .4 1.0 66 4.2 5.4 <.10 17 95 23... 17 4.2 5.5 .3 1.5 75 10 5.6 <.10 16 105 NITRO- NITRO- NITRO- NITRO- NITRO- GEN,AM- GEN, GEN, GEN, GEN, MONIA + NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC TOTAL TOTAL TOTAL TOTAL TOTAL CMG/L (MG/L (MG/L (MG/L (MG/L DATE AS N) AS N) AS N) AS N) AS N) NITRO- GEN, TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS NO3) BIOMASS CHLOR-A CHLOR-B PHYTC- CHLORO- PHYTO- PHYTO+ PHOS- PLANK- PHYLL PLANK- PLANK- PHORUS, TON, RATIO TON TON TOTAL TOTAL PLANK- CHROMO CHROMO (MG/L (CELLS TON FLUOROM FLUOROM AS P) PER ML) (UNITS) (UG/L) (UG/L) RIO GUAJATACA BASIN--CONTINUED 50010790 - LAGO DE GUAJATACA NO.1 NEAR DAM NEAR QUEBRADILLAS,PR (LAT 18° 23'56" LONG 066° 55'23") DEC , 1982 09... <.010 <.10 <.010 .50 .020 80000 .00 2.70 <.100 09... -- -- -- -- -- -- -- -- FE8 , 1933 23... -- 23... <.010 <.10 <.010 .29 .30 .40 1.9 .010 3100 .00 10.0 <.100 JUN 23... .020 <.10 <.010 .50 .020 14000 .00 3.30 <.100 23... -- RIO GRANDE DE ARECIBO BASIN--CONTINUED 50020050 - LAGO GARZAS NO.1 NEAR DAM NEAR ADJUNTAS,PR (LAT 18°08'21" LONG 066°44'35") DEC , 1982 08... <.010 .20 <.010 .30 .50 2.2 .010 15000 .00 8.10 <.100 08... -- FEB , 1983 22... <.010 <.10 <.010 .29 .30 .40 1.8 <.010 4800 .00 15.0 <.100 22... -- -- -- -- -- -- -- -- -- -- -- JUN 23... <.010 <.10 <.010 .30 .020 14000 .00 3.60 <.100 23... -- ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND. FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL. FECAL, FLOW. CON- PH TUR- OXYGEN, (PER- ICAL 0.7 KF AGAR INSTAN- DUCT- (STAND... TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) RIO GRANDE DE ARECIBO BASIN 50021000 OCT e 1982 RIO PELLEJAS AT CENTRAL PELLEJAS. PR (LAT 18°12'07" LONG 066°4216") 14... 1300 11 250 8.0 25.0 8.0 101 42 530 K130 NOV 16... 0825 15 240 7.6 21.0 8.1 96 <10 1100 5100 DEC 16... 0815 12 214 7.8 19.0 9.1 102 29 K6800 K9100 FEB . 1983 17... 0810 15 302 7.8 20.0 1.1 8.5 98 180 320 HARD- MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO- HARD- NESS. CALCIUM SUM' SODIUM, AD- SIUM, LINITY SULFATE RIDE. RIDE. NESS NONCAR- DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- (MG/L BONATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED AS (MG/L (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L DATE CAC03) CAC03) AS CA) AS MG) AS NA) AS K) CAC03) AS SO4) AS CL) AS F) OCT . 1982 14... 99 29 26 8.2 12 .5 1.3 70 40 7.3 .40 NOV 16... 88 32 23 7.4 10 .5 1.5 56 38 6.2 .10 DEC 16... 84 22 22 7.0 11 .5 1.6 62 33 7.6 .10 FEB , 1983 17... 120 45 34 8.9 12 .5 1.3 77 55 7.6 .10 SOLIDS. SOLIDS. NITRO- NITRO- SILICA. RESIDUE SUM OF SOLIDS. NITRO- NITRO- GEN. NITRO- NITRO- GEN,AM- DIS- AT 180 CONSTI- DIS- GEN. GEN, NO2+NO3 GEN, GEN, MONIA + NITRO- SOLVED DEG. C TUENTS, SOLVED NITRITE NO2+NO3 DIS- AMMONIA ORGANIC ORGANIC GEN. (MG/L DIS- DIS- (TONS TOTAL TOTAL SOLVED TOTAL TOTAL TOTAL TOTAL AS SOLVED SOLVED PER (MG/L (MG/L (MG/L (MG/L (MG/t (MG/L (MG/L DATE SI02) (MG/L) (MG/L) DAY) AS N) AS. N) AS N) AS N) AS N) AS N) AS N) OCT . 1982 14... 35 172 5.3 NOV 16... 32 152 6.2 DEC 16... 31 151 5.0 FEB 1983 17... 36 170 201 6.7 (.010 .60 .72 .83 .99 .020 .48 .50 1.1 PHOS- CHRO- PHORUS, ARSENIC BARIUM. CADMIUM MIUM. NITRO- PHOS- ORTHO, SUS- ARSENIC TOTAL BARIUM. TOTAL CADMIUM TOTAL GEN. PHORUSe DIS- ARSENIC PENDED DIS- RECOV- DIS- RECOV- DIS- RECDV- TOTAL TOTAL SOLVED TOTAL TOTAL SOLVED ERABLE SOLVED ERABLE SOLVED ERABLE (MG/L (MG/L (MG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS NO3) AS P) AS P) AS AS) AS AS) AS AS) AS BA) AS BA) AS CD) AS CD) AS CR) OCT r 1982 14... .050 NOV 16... .070 DEC 16... .050 FEB , 1983 17... 4.9 .050 1 0 1 <100 21 <1 1 10 CHRO- COBALT. COPPER. COPPER. IRON. CHRO- MIUM, COBALT. SUS- COPPER. SUS- RECOV. IRON. SUS- MIUM, RECOV. TOTAL PENDED COBALT. TOTAL PENDED COPPER. FM BOT- TOTAL PENDED CIS- FM BOT- RECOV- RECOV- DIS- RECOV- RECOV- DIS- TOM MA- RECOV- RECOV- SOLVED TOM MA- ERABLE ERABLE SOLVED ERABLE ERABLE SOLVED TERIAL ERABLE ERABLE (UG/L TERIAL (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/G (UG/L (UG/L DATE AS CR) (UG/G) AS CO) AS CO) AS CO) AS CU) AS CU) AS CU) AS CU) AS FE) AS FE) OCT , 1982 14... NOV 16... <1 3 49 DEC 16... FEB r 1983 17... <10 1 0 1 15 3 7 340 310 K = non-ideal count 209 210 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHRO- COBALT, COPPER, COPPER, IRON, CHRO- MIUM, COBALT, SUS- COPPER, SUS- RECOV. IRON, SUS- MIUM, RECOV. TOTAL PENDED COBALT, TOTAL PENDED COPPER, FM BOT- TOTAL PENDED DIS- FM BOT- RECOV- RECOV- DIS- RECOV- RECOV- DIS- TOM MA- RECOV- RECOV-- SOLVED TOM MA- ERABLE ERABLE SOLVED ERABLE ERABLE SOLVED TERIAL ERABLE ERABLE (UG/L TERIAL (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/G (UG/L (UG/L DATE AS CR) LUG/G) AS CO) AS CO) AS CO) AS CU) AS CU) AS CU) AS CU) AS FE) AS FE) RIO GRANDE DE ARECIBO BASIN--CONTINUED 50021000 RIO PELLEJAS AT CENTRAL PELLEJAS, PR (LAT 18°12'07" LONG 066°42'16") OCT • 1982 14... NOV 16... <1 3 49 DEC 16... FEB • 1933 17... <10 1 0 1 15 8 7 340 310 MANGA- MANGA- NICKEL, LEAD, NESE, NESE, MANGA- MERCURY NICKEL, SUS- IRON, TOTAL LEAD, TOTAL SUS- NESE, TOTAL MERCURY TOTAL PENDED NICKEL, DIS- RECOV- DIS- RECOV- PENDED DIS- RECOV- DIS- RECOV- RECOV- DIS- SOLVED ERABLE SOLVED ERABLE RECOV. SOLVED ERABLE SOLVED ERABLE ERABLE SOLVED (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS FE) AS PB) AS PB) AS MN) AS MN) AS MN) AS HG) AS MG) AS NI) AS NI) AS NI) OCT , 1932 14... 45 NOV 16... 63 DEC 16... 43 FEB r 1933 17... 30 <1 <1 9 16 <1 10 10 4 6 .2 <.1 23 24 4 NICKEL, ZINC, SEDI- RECOV. SELE- SILVER, ZINC, RECOV. MINT, FM SOT- SELE- NIUM, TOTAL SILVER, TOTAL ZINC, FM BOT- SEDI- OIS- TOM MA- NIUM, CIS- RECOV- DIS- RECOV- DIS- TOM MA- MENT, CHARGE', TERIAL TOTAL SOLVED ERA3LE SOLVED ERABLE SOLVED TERIAL SUS- SUS- (UG/G (UG/L (UGIL (UG/L (UG/L (UG/L (UG/L (UG/G PENDED PENDED DATE AS NI) AS SE) AS SE) AS AG) AS AG) AS ZN) AS ZN) AS ZN) (MG/L) (T/DAY) OCT , 1982 14... 9 .27 NOV 16... <10 20 DEC 16... 26 .87 FEB r 1 983 17... <1 <1 <1 <1 30 <3 QUALITATIVE AND ASSOCIATED QUANTITATIVE ANALYSES CF BIOLOGICAL DATA, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 BENTHIC INVERTEBRATES DATE OCT 14,32 TIME 1300 TOTAL COUNT 68 DIVERSITY: PHYLUM 0.0 .CLASS 0.0 ..ORCER 0.1 ...FAMILY 0.1 ....GENUS 0.7 ....GENUS-INSECTA 0.7 ORGANISM COUNT ARTHROPODA (ARTHROPODS) .INSECTA ..DIPTERA ...CHIRONOMIDAE ....CRICOTOPUS ....THIENEMANNIELLA ..000NATA ...LIBELLULIOAE ....MACROTHEMIS 56 11 1 ANALYSES OF SAMPLES CJLLECTED AT WATER-QUALLITY PARTIAL-RECORD STATIONS WATER QUALITY DA TA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 SED. M- SUSP. STREAM- SE SIEVE FLOW, MENT, DIAM. INSTAN- SUS- % FINER TIME TANEOUS PENDED THAN DATE (CFS) (MG/L) .062 MM RIO GRANDE DE ARECIBO BASIN--CONTINUED 50021000 RIO PELLEJAS AT CENTRAL PELLEJAS, PR (LAT 18°12'07" LONG 066°42'16") OCT r 11932 14... 1300 11 4 75 SED. SED. SED. SED. SED. SED. SED. BED SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. MAT. STREAM- FALL FALL FALL FALL FALL FALL SIEVE FALL FLOW, DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. INSTAN- B FINER 7( FINER X FINER % FINER % FINER % FINER % FINER B FINER TIME TANEOUS THAN THAN THAN THAN THAN THAN THAN THAN DATE (CFS) .002 MM .004 MM .008 MM .016 MM .031 MM .062 MM .062 MM .004 MM DEC , 1982 16... 0815 12 0 0 1 15 21 3 46 0 FEB , 1983 17... 0810 15 1 1 1 1 2 4 4.2 1 BED BED BED BED BED BED BED BED MAT. MAT. MAT MAT. MAT. MAT. MAT. MAT. FALL SIEVE SIEV SIEVE SIEVE SIEVE SIEVE SIEVE DIAM. DIAM. DIA . DIAM. 'HAM. DIAM. DIAM. DIAM. % FINER % FINER B FINR % FINER % FINER B FINER % FINER 7( FINER THAN THAN THA THAN THAN THAN THAN THAN DATE .062 MM .062 MM .125 MM .250 MM .500 MM 1.00 MM 2.00 MM 4.00 MM DEC 16... 3 3 FEB 17... 4 4 5 9 16 30 50 71 5 7 13 24 38 51 211 HARD- NESS, NONCAR- BONATE (MG/L DATE CAC03) CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM. DI S- SOLVED (MG/L AS NA) OCT • 1932 NITRO- GEN, TOTAL (MG/L AS N) NITRO- GEN. TOTAL (MG/L AS NO3) PHOS- PHORUS, TOTAL (MG/L AS P) PHOS- PHORUS, ORTHO, DIS- SOLVED (MG/L AS P) 212 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER QUALITY DATA, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 OXYGEN, OXYGEN COLI- STREP- SPE- DIS- DEMAND, FORM, TOCOCCI STREAM- CIFIC SOLVED CHEM- FECAL, FECAL, HARD- FLOW, CON- PH TUR- OXYGEN. (PER- 1CAL 0.7 KF AGAR NESS INSTAN- DUCT- (STAND- TEMPER- BID- DIS- CENT (HIGH UM-MF (COLS. (MG/L TIME TANEOUS ANCE ARD ATURE ITY SOLVED SATUR- LEVEL) (COLS./ PER AS DATE (CFS) (UMHOS) UNITS) (DEG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) CAC03) RIO GRANDE DE ARECIBO BASIN 50023000 RIO VIVI NEAR CENTRAL PELLEJAS, PR (LAT 18°12'52" LONG 066°40'25") OCT , 1962 20... 1245 15 216 7.6 23.0 7.9 96 30 3500 200 78 NOV 16... 1235 13 240 7.5 22.0 7.9 96 <10 700 1800 86 OEC 16... 1140 12 242 7.5 19.0 9.2 104 47 K80 K170 82 FEB , 1983 17... 1145 5.0 253 7.8 21.0 1.2 8.1 95 K26 100 95 SOLIDS, SODIUM POTAS- ALKA- CHLO- FLUO- SILICA, RESIDUE AO- SIUM, LINITY SULFATE RIDE, RIDE, DIS'" AT 180 SORP- DIS- FIELD DIS- DES- DIS- SOLVED DEG. C TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L DIS- RATIO (MG/L AS (MG/L (MG/L (MG/L AS SOLVED AS K) CAC03) AS SO4) AS CL) AS F) SI02) (MG/L) 20... 34 20 6.8 9.0 .5 1.7 44 37 7.5 <.10 28 NOV 16... 42 22 7.5 11 .5 1.8 44 44 7.3 .10 32 DEC 16... 33 21 7.1 10 .5 1.8 44 36 3.0 .10 31 FEB , 1983 17... 34 25 7.3 11 .5 1.6 61 61 3.6 .10 31 146 SOLIDS, NITRO- NITRO- SUM OF SOLIDS, NITRO- NITRO- GEN, NITRO- NITRO- GEN,AM- CONSTI- OIS- GEN, GEN, NO2+NO3 GEN, GEN, MONIA + TUENTS, SOLVED NITRITE NO2+NO3 DIS- AMMONIA ORGANIC ORGANIC On- (TONS TOTAL TOTAL SOLVED TOTAL TOTAL TOTAL SOLVED PER (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L DATE (MG/L) DAY) AS N) AS N) AS N) AS N) AS N) AS N) OCT , 1932 20... 137 5.7 NOV 16... 152 5.3 DEC 16... 141 4.7 FEB r 1983 17... 183 2.0 (.010 .60 .87 1 . 0 .90 .020 .44 .50 1.1 4.9 .030 .020 .040 .010 CHRO- CHRO- CHRO- ARSENIC BARIUM, CADMIUM MIUM, MIUM, CHRO- MIUM, SUS- ARSENIC TOTAL BARIUM, TOTAL CADMIUM TOTAL SUS-" MIUM, RECOV. ARSENIC PENDED DIS- RECOV- DIS- RECOV- DIS- RECOV- PENDED DIS- FM BOT•"- TOTAL TOTAL SOLVED ERABLE SOLVED ERABLE SOLVED ERABLE RECOV. SOLVED TOM MA- (LIG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L TERIAL DATE AS AS) AS AS) AS AS) AS BA) AS BA) AS CD) AS CD) AS CR) AS CR) AS CR) LUG/G) OCT r 1932 20... NOV 16... DEC 16... FEB , 1983 17... 1 0 1 <100 24 <1 <1 3 2 10 0 10 COBALT, COPPER, COPPER., IRON, COBALT, SUS- COPPER, SUS- RECOV. IRONe SUS- LEADe TOTAL PENDED COBALT, TOTAL PENDED COPPER, FM BOT- TOTAL PENDED IRON, TOTAL RECOV- RECOV- DIS- RECOV- RECOV- DIS- TOM MA- RECOV- RECOV- DIS- RECOV- ERABLE ERABLE SOLVED ERABLE ERABLE SOLVED TERIAL ERABLE ERABLE SOLVED ERABLE (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/G (UG/L (UG/L (UG/L (UG/L DATE AS CO) AS CO) AS CO) AS CU) AS CU) AS CU) AS CU) AS FE) AS FE) AS FE) AS PB) OCT , 1932 20... NOV 16... DEC 16... FEB ,1933 17... 38 63 10 9 1 0 1 39 25 14 250 240 10 2 K = non-ideal count 213 ANALYSES OF SAMPLES COLLE TED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 COBALT, COPPER. COPPER, IRON. COBALT, SUS- COPPER, SUS- RECOV. IRON, SUS- LEAD. TOTAL PENDED COBALT, TOTAL PENDED COPPER, FM BOT- TOTAL PENDED IRON. TOTAL RECOV- RECOV- DIS- RECOV-. RECOV- DIS- TOM MA- RECOV- RECOV- DIS- RECOV- ERABLE ERABLE SOLVED ERABLE ERABLE SOLVED TERIAL ERABLE ERABLE SOLVED ERABLE (UG/L (UG/L (UG/L (UG/L CUG/L (UG/L (UG/G (UG/L (UG/L (UG/L (UG/L DATE AS CO) AS CO) AS CO) AS CU) AS CU) AS CU) AS CU) AS FE) AS FE) AS FE) AS PB) RIO GRAND E DE ARECIBO BASIN--CONTINUED 50023000 RIO VIVI NEAR CENT RAL PELLEJAS, PR (LAT 18012'52" LONG 066°40'25") OCT , 1982 20... NOV 16... DEC 16... FEB r 1983 17... 1 39 25 14 38 63 10 9 250 240 10 1 0 2 LEAD, MANGA- MANGA- MERCURY NICKEL, SUS- NESE, NESE, MANGA- MERCURY SUS- NICKEL, SUS- PENDED LEAD, TOTAL SUS- NESE, TOTAL PENDED MERCURY TOTAL FENDED NICKEL. RECOV- DIS- RECOV- PENDED DIS- RECOV- RECOV- DIS- RECOV- RECOV- On- ERABLE SOLVED ERABLE RECOV. SOLVED ERABLE ERABLE SOLVED ERABLE ERABLE SOLVED (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L (UG/L DATE AS PB) AS PB) AS MN) AS MN) AS MN) AS HG) AS HG) AS HG) AS NI) AS NI) AS NI) OCT r 1982 20... NOV 16... DEC 16... FEB r 1983 17... 0 2 20 NICKEL. RECOV. SELE- SILVER. FM LOT- SELE- NIUM, TOTAL TOM MA- NIUM, DIS- RECOV- TERIAL TOTAL SOLVED ERABLE (UG/G (UG/L (UG/L (UG/L DATE AS NI) AS SE) AS SE) AS AG) 19 24 2 15 17 .2 16 11 5 ZINC. ZINC. SEDI- ZINC. SUS- RECOV. MENT, SILVER. TOTAL PENDED ZINC, FM BOT- SEDI- DIS- On- RECOV- RECOV- DIS- TOM MA- MENT, CHARGE. SOLVED ERABLE ERABLE SOLVED TERIAL SUS- SUS- (UG/L (UG/L (UG/L (UG/L (UG/G PENDED PENDED AS AG) AS ZN) AS ZN) AS ZN) AS ZN) (MG/L) (T/DAY) <1 OCT , 1982 20... NOV 16... <10 DEC 16... FEB . 1983 17... 4 .16 70 59 2.1 18 .58 <1 <1 <1 30 30 5 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER QUALITY DATA, WATER YEAR OCTOBER 1982 TU SEPTEMBER 1983 SED. SUSP. STREAM- SEDI- SIEVE FLOW, MENT, BEAM. INSTAN- SUS- X FINER TIME TANEOUS PENDED THAN DATE (CFS) (MG/L) .062 MM RIO GRANDE OE ARECIBO BASIN—Continued 50023000 RIO VIVI NEAR CENTRAL PELLEJAS, PR (LAT 18°12'52" LONG 066°40'25") OCT 1932 20... 1245 15 9 56 NOV 16... 1235 13 113 67 SED. SED. SED. SED. SED. SED. SED. BED SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. MAT. STREAM- FALL FALL FALL FALL FALL FALL SIEVE FALL FLOW, DIAM. DIAM. DIAM. ()TAM. DIAM. DIAM. DIAM. DIAM INSTAN- X FINER A FINER X FINER X FINER X FINER X FINER X FINER FINER TIME TANEOUS THAN THAN THAN THAN THAN THAN THAN THAN DATE (CFS) .002 MM .004 MM .003 MM .016 MM .031 MM .062 MM .062 MM .004 MM DEC , 1982 16... 1140 12 0 0 0 0 0 3 97 0 FEB , 1983 17... 1145 5.0 0 0 0 0 1 3 3.0 0 BED BED BED BED BED BEC BED BED MAT. MAT. MAT. MAT. MAT. MAT. MAT. MAT. FALL SIEVE SIEVE SIEVE SIEVE SIEVE SIEVE SIEVE DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. X FINER X FINER X FINER X FINER X FINER X FINER X FINER X FINER THAN THAN THAN THAN THAN THAN THAN THAN DATE .062 MM .062 MM .125 MM .250 MM .500 MM 1.00 MM 2.00 MM 4.00 MM DEC 16... 0 3 3 6 13 30 53 71 88 FEB 17... 0 3 3 4 6 14 30 47 63 214 SAM- PLING TIME DEPTH (FEET) SPE- CIFIC CON- DUCT- ANCE (UMHOS) PH (STAND- ARD UNITS) DATE SAM- PLING TIME DEPTH (FEET) SPE- CIFIC CON- DUCT- ANCE (UMHOS) PH (STAND- ARD UNITS) DATE 215 ANALYSES OF SAMPLES CO LLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER-QUALITY DATA . WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 SPE- CIFIC CON- PH DUCT- (STAND- T ANCE ARD (UMHOS) UNITS) OXYGEN,. COLI- STREP- SOLIDS. DIS- FORM. TOCOCCI ALKA- RESIDUE NITRO- SOLVED FECAL, FECAL, LINITY AT 105 GEN, OXYGEN, (PER- 0.7 KF AGAR FIELD DEG. Cr NITRATE EMPER- DIS- CENT UM-MF (COLS. (MG/L SUS- TOTAL ATURE SOLVED SATUR- (COLS./ PER AS PENDED (MG/L DEG C) (MG/L) ATION) 100 ML) 100 ML) CAC03) (MG/L) AS N) SAM- PLING TIME DEPTH DATE (FEET) RIO GRANDE DE ARECIBO BASIN 50025110 - LAGO DOS BOCAS NO. AT WEST BRANCH NEAR UTUADO,PR (LAT 1819'15" LONG 066°40'11") DEC 1982 09... 1045 FEB . 1983 23... 0925 JUN 22... 1345 1.00 203 8.5 1.00 226 7.2 1.00 200 8.4 25.5 13.6 168 K87 K2 77 <1 .18 24.5 7.2 87 250 Kll 79 10 .07 30.5 10.2 138 K7 K5 74 .19 OXYGEN, COLI- STREP- SOLIDS. DIS- FORM. TOCOCCI RESIDUE HARD- SOLVED FECAL, FECAL. AT 105 HARD- NESS., OXYGEN. (PER- 0.7 KF AGAR DEG. C. NESS NONCAR- EMPER- DIS- CENT UM-MF (COLS. SUS- (MG/L BONATE ATURE SOLVED SATUR- (COLS./ PER PENDED AS (MG/L DEG C) (MG/L) ATION) 100 ML) 100 ML) (MG/L) CAC03) CAC03) 50027090 - LAGO DOS BOCA1 NO.1 NEAR DAM NEAR UTUADO,PR (LAT 18° 20'09" LONG 066°40'04") DEC . 1982 09... 0945 1.00 186 7.9 25.0 10.2 125 K9 K7 <1 66 0 09... 1000 78.0 196 6.7 23.5 .0 0 -- -- 70 0 FES r 1953 23... 1000 1.00 213 7.8 24.5 8.7 105 90 K6 <1 80 12 23... 1005 84.0 216 6.6 23.5 .0 0 -- 76 1 JUN 22... 1300 1.00 201 8.3 31.0 9.7 132 K12 K13 <1 78 4 22... 1310 84.0 203 6.5 25.0 .0 0 -- -- 73 0 OXYGEN. COLI- STREP- SOLIDS, DIS- FORM, TOCOCCI ALKA- RESIDUE NITRO- SOLVED FECAL, FECAL, LINITY AT 105 GEN, OXYGEN, (PER- 0.7 KF AGAR FIELD DEG. Cr NITRATE EMPER- DIS- CENT UM-MF (COLS. (MG/L SUS- TOTAL ATURE SOLVED SATUR- (COLS./ PER AS PENDED (MG/L DEG C) (MG/L) ATION) 100 ML) 100 ML) CAC03) (MG/L) AS N) 50039900 LAGO CARITE NO.3 0 RIO DE LA PLATA BASIN RIO DE LA PLATA NEAR CAYEY.PR (LAT 18'05'04" LONG 066°06'03") DEC , 1982 14... 1205 FEB , 1983 24... 1050 JUN 27... 1215 1.00 95 7.3 1.00 105 7.7 1.00 99 7.6 23.5 8.3 104 K4 K4 31 17 23.0 8.6 106 K3 K1 38 6 27.5 8.3 112 K16 120 33 <1 OXYGEN, COLI- STREP- SOLIDS. DIS- FORM, TOCOCCI RESIDUE HARD- SOLVED FECAL, FECAL. AT 105 HARD- NESS, OXYGEN, (PER- 0.7 KF AGAR DEG. Cr NESS NONCAR- EMPER- DIS- CENT UM-MF (COLS. SUS- (MG/L BONATE ATURE SOLVED SATUR- (COLS./ PER PENDED AS (MG/L DEG C) (MG/L) ATION) 100 ML) 100 ML) (MG/L) CAC03) CAC03) 0.1 NEAR DAM NEAR CAYEY.PR (LAT 18°04'39" LONG 066'06'19") SPE- CIFIC SAM- CON- PH PLING DUCT- (STAND- TIME DEPTH ANCE ARD DATE (FEET) (UMHOS) UNITS) 50039950 - LAGO CARITE DEC r 1932 14... 1130 1.00 93 7.0 23.5 7.3 91 K2 K9 <1 28 0 14... 1140 63.0 169 6.5 21.5 .0 0 -- 29 0 FEB , 1983 24... 1035 59.0 122 6.3 21.5 .0 0 -- 31 0 24... 1040 1.00 106 7.7 23.0 8.7 108 K3 <1 <1 31 0 JUN 27... 1140 1.00 99 7.5 27.5 7.4 100 K9 44 2 26 0 K = non-ideal count 216 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER-QUALITY DATA, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 NITRO- BIOMASS CHLOR-A CHLOR-B NITRO- NITRO- NITRO- NITRO- GEN,AM- PHYTO- CHLORO- PHYTO- PHYTO- GEN, GEN, GEN, GEN, MONIA + NITRO- NITRO- PHOS- PLANK- PHYLL PLANK- PLANK- NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEN, PHORUS, TON, RATIO TON TON TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL PLANK- CHROMO CHROMO (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (CELLS TON FLUOROM FLUOROM DATE AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) AS P) PER ML) (UNITS) (UG/L) (UG/L) RIO GRANDE DE ARECIBO BASIN--CONTINUED 50025110 LAGO DOS BOCAS NO.3 AT WEST BRANCH NEAR UTUADO,PR (LAT 18° 19.15" LONG 066°40'11") SODIUM AD- SORP- TION RATIO DEC 1982 09... .020 .20 <.010 FEB , 1983 23... .030 .10 <.010 JUN 22... .010 .20 <.010 MAGNE- CALCIUM SLUM, SODIUM, DIS- DIS- DIS- SOLVED SOLVED SOLVED (MG/L (MG/L (MG/L DATE AS CA) AS MG) AS NA) 1.10 1.3 5.8 .090 86000 .00 53.0 <.100 .50 .50 2.7 .040 64000 .00 18.0 <.100 .30 .50 2.2 .020 26000 .00 4.50 <.100 SOLIDS, POTAS- ALKA- CHLO- FLUO- SILICA, SUM OF NITRO- SIUM, LINITY SULFATE RIDE, RIDE, DIS- CONSTI- GEN, DIS- FIELD DIS- DIS- DIS- SOLVED TUENTS, NITRATE SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L DIS- TOTAL (MG/L AS (MG/L (MG/L (MG/L AS SOLVED (MG/L AS K) CAC03) AS SO4) AS CL) AS F) SI02) (MG/L) AS N) 50027090 - LAGO DOS BOCAS NO.1 NEAR DAM NEAR UTUADO,PR (LAT 13°20'09" LONG 066°40'04") DEC , 1982 09... 17 5.6 10 .6 1.3 71 3.0 7.5 <.10 17 109 09... 19 5.4 9.6 .5 2.0 71 8.0 8.9 <.10 22 117 FEB , 1983 23... 21 6.8 12 .6 2.1 69 15 9.2 .10 18 126 23... 20 6.3 11 .6 2.1 75 15 9.2 .10 16 125 JUN 22... 21 6.1 10 .5 1.3 74 13 10 .10 22 128 .18 22... 20 5.7 9.3 .5 2.0 75 10 10 .10 20 122 -- NITRO- BIOMASS CHLOR-A CHLOR-B NITRO- NITRO- NITRO- NITRO- GEN,AM- PHYTO- CHLORO- PHYTO- PHYTO- GEN, GEN, GEN, GEN, MONIA + NITRO- NITRO- PHOS- PLANK- PHYLL PLANK- PLANK- NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEN, PHORUS, TON, RATIO TON TON TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL PLANK- CHROMO CHROMO (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (CELLS TON FLUOROM FLUOROM DATE AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) AS P) PER ML) (UNITS) (UG/L) (UG/L) RIO DE LA PLATA BASIN--CONTINUED 50039900 - LAGO CARITE NO.3 ON RIO OE LA PLATA NEAR CAYEY,PR (LAT 18°05'04" LONG 066°06',03") DEC , 1982 14... <.10 .020 .63 .70 .030 33000 .00 6.10 1.20 FEB e 1983 24... <.10 <.010 .30 .030 7800 .00 15.0 <.100 JUN 27... <.10 <.010 .30 .020 59000 .00 3.40 <.100 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM AD- SORP- TION RATIO CALCIUM DIS- SOLVED (MG/L DATE AS CA) SODIUM, DIS- SOLVED (MG/L AS NA) POTAS- ALKA- SIUM, LINITY DIS- FIELD SOLVED (MG/L (MG/L AS AS K) CAC03) SULFATE DIS- SOLVED (MG/L AS SO4) SOLIDS, CHLO- FLUO- RIDE, RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CL) AS F) SILICA, SUM OF NITRO- DIS- CONSTI- GEN, SOLVED TUENTS, NITRATE (MG/L DIS- TOTAL AS SOLVED (MG/L SI02) (MG/L) AS N) 50039950 - LAGO CARITE NO.1 NEAR DAM NEAR CAYEY.PR (LAT 18°04.39" LONG 066°06'19") DEC , 1982 14... 5.7 3.4 3.0 .7 .3 33 2.0 8.1 <.10 19 67 14... 6.0 3.3 7.9 .7 .9 48 3.0 S.4 <.10 19 77 FEB , 1983 24... 6.4 3.7 8.1 .6 .3 39 3.2 9.0 <.10 20 75 24... 6.3 3.7 3.0 .6 .8 36 3.4 9.4 .10 19 72 JUN 27... 5.0 3.2 7.3 .6 .3 39 4.1 9.4 <.10 18 71 ANALYSES OF SAMPLES C WATER-QUALITY DAT SAM- PLING TIME DEPTH (FEET) SPE- CIFIC CON- PH DUCT- (STAND- ANCE ARD (UMHOS) UNITS) DATE SPE- CIFIC SAM- CON- PH PLING DUCT- (STAND- TIME ANCE DEPTH ARD (FEET) (UMHOS) UNITS) DATE 217 LLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS , WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 OXYGEN, COLI- STREP- SOLIDS, DIS- FORM, TOCOCCI ALKA- RESIDUE NITRO- SOLVED FECAL, FECAL, LINITY AT 105 GEN, OXYGEN, (PER- 0.7 KF AGAR FIELD DEG. Cr NITRATE EMPER- DIS- CENT UM-MF (COLS. (MG/L SUS- TOTAL ATURE SOLVED SATUR- (COLS./ PER AS PENDED (MG/L DEG C) (MG/L) ATION) 100 ML) 100 ML) CAC03) (MG/L) AS N) 50044400 LAGO LA PLATA NO. RIO DE LA PLATA BASIN NEAR MOUTH NEAR NARANJITO, PR (LAT 18619'33" LONG 066°12'28") DEC r 1982 07... 1145 FEB , 1933 18... 1100 JUN 21... 1145 1.00 233 7.4 1.00 402 7.1 1.00 314 7.2 25.5 9.9 121 K50 316 84 8 .78 25.0 4.5 55 K12 K2 149 13 .38 28.5 5.5 71 250 K800 91 .57 OXYGEN, COLI- STREP- SOLIDS, DIS- FORM, TOCOCCI RESIDUE HARD- SOLVED FECAL, FECAL, AT 105 HARD- NESS. OXYGEN, (PER- 0.7 KF AGAR CEG. Cr NESS NONCAR- EMPER- DIS- CENT UM-MF (COLS. SUS- (MG/L BONATE ATURE SOLVED SATUR- (COLS./ PER PENDED AS (MG/L DEG C) (MG/L) ATION) 100 ML) 100 ML) (MG/L) CAC03) CAC03) 50044950 LAGO LA PLATA NO.3 NEAR DAM NEAR NARANJITO, PR (LAT 18°20'18" LONG 066°14'01") DEC r 1982 07... 1045 1.00 255 7.2 24.5 7.5 90 31 16 93 3 07... 1100 74.0 433 7.2 23.5 .0 0 83 0 FEB , 1983 13... 1220 1.00 321 6.7 26.0 3.8 47 Kll K16 8 120 4 18... 1230 67.0 282 6.6 22.5 .0 0 -- 100 4 JUN 21... 1040 1.00 266 6.9 29.0 5.1 67 56 140 16 89 0 21... 1050 70.0 261 6.5 23.5 .0 0 -- 92 C DATE SAM- PLING TIME DEPTH (FEET) SPE- CIFIC CON- PH DUCT- (STAND- ANCE ARD (UMHOS) UNITS) OXYGEN, EMPER- DIS- ATURE SOLVED DEG C) (MG/L) OXYGEN, COLT- STREP- SOLIDS, DIS- FORM. TOCOCCI ALKA- RESIDUE NITRO- SOLVED FECAL, FECAL, LINITY AT 105 GEN. (PER- 0.7 KF AGAR FIELD DEG. Cr NITRATE CENT UM-MF (COLS. (MG/L SUS- TOTAL SATUR- (COLS./ PER AS PENDED (MG/L ATION) 100 ML) 100 ML) CAC03) (MG/L) AS N) RIO GRANDE DE LOIZA BASIN 50057500 - LAGO LOIZA NO. NEAR MOUTH NEAR CAGUAS, PR (LAT 18°16'51" LONG 066.00'35") DEC , 1982 10... 1150 FEB , 1983 17... 1315 JUN 24... 1115 1.00 221 7.2 1.00 352 6.8 1.00 231 6.9 27.0 13.0 164 K790 <10 79 12 .61 25.0 2.5 30 24000 K52 114 14 .39 29.5 2.5 33 6600 530 72 .53 DATE OXYGEN. COLI- STREP- SOLIDS, SPE- DIS- FORM, TOCOCCI RESIDUE HARD- CIFIC SOLVED FECAL, FECAL, AT 105 HARD- NESS. SAM- CON- PH OXYGEN, (PER- 0.7 KF AGAR CEG. Co NESS NONCAR PLING DUCT- (STAND- TEMPER- CIS- CENT UM-MF (COLS. SUS- (MG/L BONATE TIME DEPTH ANCE ARD ATURE SOLVED SATUR- (COLS./ PER PENDED AS (MG/L (FEET) (UMHOS) UNITS) (DEG C) (MG/L) ATION) 100 ML) 100 ML) CMG/L) CAC03) CAC03) 50058800 LAGO LOIZA NO.7 NEAR DAM NEAR TRUJILLO ALTO, PR (LAT 18°19'29" LONG 066°00'47") DEC • 1982 10... 1105 10... 1110 FEB , 1983 17... 1200 17... 1210 JUN 24... 1045 24... 1050 1.00 201 7.1 25.5 237 6.6 29.0 314 6.4 1.00 289 6.8 1.00 187 6.9 37.0 147 6.4 26.0 8.1 100 K23 K2 <1 59 24.0 .0 0 55 25.0 .0 0 -- 96 0 26.0 8.1 100 <2 <2 90 29.5 4.1 54 230 740 20 53 26.5 .0 0 40 1 K = non-ideal count 218 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER-QUALITY DATA. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 NITRO- BIOMASS CHLOR-A CHLOR..-8 NITRO- NITRO- NITRO- NITRO- GENRAM- PHYTO- CHLOR0-.. PHYTO-. PHYTO- GEN, GEN. GEN. GEN. MONIA + NITRO- NITRO- PHOS- PLANK- PHYLL PLANK- PLANK- NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN. GEN. PHORUS, TON, RATIO TON TON TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL PLANK- CHROMO CHROMO (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (CELLS TON FLUOROM FLUOROM DATE AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) AS P) PER ML) (UNITS) (UG/L) (UG/L) RIO GRANDE OE ARECIBO BASIN--CONTINUED 50027090 LAGO DOS BOCAS NO.1 NEAR DAM NEAR UTUADOrPR (LAT 18°20'09" LONG 066°40'04") DEC f 1982 09... <.010 .20 ‹.010 .40 .60 2.7 .020 170000 .00 9.40 .800 09.. -- -- -- FEB .•1983 23... .020 <.10 <.010 .40 .020 180000 .00 5.60 <.100 23... -- -- -- JUN 22... .020 .20 <.010 .40 .60 2.7 .030 77000 .00 3.60 <.100 22... -- -- -- -- RIO RIO OE LA PLATA BASIN--CONTINUED 50039950 - LAGO CARITE NO.1 NEAR DAM NEAR CAYEY.PR (LAT 18°04'39" LONG 066°06'19") DEC r 1982 14... <.010 <.10 .030 .67 .70 .050 26000 .00 6.40 1.40 14.. -- -- -- ..- FEB .•1983 24... -- -.. -- 24... <.010 <.10 .020 .38 .40 .030 5700 .00 5.80 <.100 JUN 27... (.010 <.10 <.010 .30 .010 48000 .00 3.20 <.100 50044950 - LAGO LA PLATA NO.3 NEAR DAM NEAR NARANJITO. PR (LAT 18°20'18" LONG 066°14'01") DEC , 1982 07... .010 .30 <.010 .30 .60 2.7 .170 13000 .00 14.0 <.100 07... -- -- - FEB • 1983 18... <.010 <.10 .020 .68 .70 .070 9200 .00 10.0 <.100 18... •••••• -- JUN 21... .020 .40 .030 .47 .50 .90 4.0 .110 37000 .00 13.0 <.100 21... -- -- -- -- -- RIO GRANDE DE LOIZA BASIN--CONTINUED 50058800 LAGO LOIZA NO.7 NEAR DAM NEAR TRUJILLO AL.(/' PR (LAT 18°19'29" LONG 066°00'47") DEC , 1962 10... .050 .50 .020 .78 .80 1.3 5.8 .140 47000 .00 14.0 <.100 10... •••••• FEB , 1983 17... -- 17... .030 <.10 .020 .98 1.00 .190 12000 .00 28.0 <.100 JUN 24... .200 .60 .270 .43 .70 1.3 5.8 .220 26000 .00 6.40 <.100 24... -- -- -- 219 ANALYSES OF SAMPLES COL LECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 NITRO- BIOMASS CHLOR-A CHLOR-B NITRO- NITRO- NITRO- NITRO- GEN,AM.. PHYTO- CHLORO- PHYTO- PHYTO- GEN, GEN. GEN. GEN. MONIA + NITRO- NITRO- PHOS- PLANK- PHYLL b PLANK- PLANK- NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEN. PHORUS. TON. RATIO TON TON TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL PLANK- CHROMO CHROMO (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (CELLS TON FLUOROM FLUOROM DATE AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) AS P) PER ML) (UNITS) (UG/L) (UG/L) RIO 50044400 LAGO LA PLATA NO.5 DEC 1982 07... .020 .80 .020 .38 FEB , 1933 18... .020 .40 .050 .65 JUN 21... .030 .60 .060 .34 I LA PLATA BASIN--CONTINUED NEAR MOUTH NEAR NARANJITOr PR (LAT 18°19'33" LONG 066°12'28") .40 1.2 5.3 .220 1100 .00 1.20 <.100 .70 1.1 4.9 .160 7900 .00 6.90 <.100 .40 1.0 4.4 .140 3100 .00 .800 <.100 SOLIDS, MAGNE- SODIUM POTAS- ALKA- CHLO- FLUO.". SILICA, SUM OF NITRO- CALCIUM SIUM, SODIUM, AD- SIUM, LINITY SULFATE RIDE, RIDE. DIS- CONSTI- GEN, DIS- DIS- DIS- SORP- DIS- FIELD DIS- DIS- DIS- SOLVED TUENTS, NITRATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L DIS- TOTAL (MG/L (MG/L (MG/L RATIO (MG/L AS (MG/L (MG/L (MG/L AS SOLVED (MG/L DATE AS CA) AS MG) AS NA) AS K) CAC03) AS 504) AS CL) AS F) SI02) (MG/L) AS N) 50044950 - LAGO LA PLATA NO.3 NEAR DAM NEAR NARANJITO. PR (LAT 18°20'18" LONG 066°14'01") DEC r 1982 07... 22 07... 20 FEB , 1933 18... 30 18... 25 JUN 21... 21 21... 22 9.3 17 .8 8.1 15 .7 12 18 .7 9.6 14 .6 8.8 16 .8 9.1 14 .7 2.3 90 11 16 .10 21 153 .29 2.5 84 11 14 .10 23 144 -- 1.4 120 15 21 .20 22 192 2.6 98 11 15 .10 23 159 2.7 120 13 19 .20 21 174 .38 3.4 110 10 17 .20 21 163 -- NITRO- BIOMASS CHLOR-A CHLOR-8 NITRO- NITRO- NITRO- NITRO- GEN,AM- PHYTO- CHLORO- PHYTO... PHYTO- GEN, GEN, GEN, GEN, McNIA + NITRO- NITRO- PHOS- PLANK- PHYLL b PLANK- PLANK- NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN. GEN. PHORUS, TON, RATIO TON TON TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL PLANK- CHROMO CHROMO (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (CELLS TON FLUOROM FLUOROM DATE AS N) AS N) AS N) AS N) AS N) AS N) AS N05) AS P) PER ML) (UNITS) (UG/L) (UG/L) RIO GRAls DE DE LOIZA BASIN--CONTINUED 50057500 LAGO LOIZA NO.4 NEAR MOUTH NEAR CAGUAS, PR (LAT 18°16'51" LONG 066°00'35") DEC 1932 10... .090 .70 .340 .76 1.10 FEB , 1983 17... .110 .50 1.40 1.0 2.40 JUN 24... .070 .60 .710 .79 1.50 1.8 8.0 .270 16000 .00 15.0 <.100 2.9 13 .630 5500 .00 17.0 2.10 2.1 9.3 .350 2600 .00 2.50 <.100 SOLIDS, MAGNE- CALCIUM SIUM, DIS- DIS- SODIUM, DES- SODIUMPOTAS- AD- SORP- SIUM, DIS- ALKA- LiNiTy FIELD SULFATE DIS- CHLO- RIDE. DIS- FLUO- RIDE, DIS- SILICA, DIS- SOLVED SUM OF CONSTI- TUENTS. NITRO- GEN, NITRATE SOLVED SOLVED SOLVED TION SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L OIS- TOTAL (MG/L (MG/L (MG/L RATIO MG/L AS (MG/L (MG/L (MG/L AS SOLVED (MG/L DATE AS CA) AS MG) AS NA) AS K) CAC03) AS 504) AS CL) AS F) SI02) (MG/L) AS N) DEC , 10... 50058800 1932 14 5.9 - LAGO 17 LOIZA NO.7 1.0 NEAR DAM NEAR TRUJILLO ALTO, 2.5 59 12 PR (LAT 15 18°19'29" LONG .10 23 066°00'47") 125 .45 10... 13 5.5 15 .9 2.7 69 11 15 .10 23 127 -- FEB r 1983 17... 23 9.3 25 1.1 2.0 100 14 21 .20 27 181 17... 21 9.2 26 1.2 1.8 96 14 20 .20 25 175 JUN 24... 13 4.9 15 .9 2.6 53 13 14 .20 23 117 .40 24... 9.9 3.6 10 .7 2.5 39 10 10 .20 17 87 220 ANALYSES OF SAMPLES COLLECTED AT WATER-OUALITY PARTIAL-RECORD STATIONS WATER-QUALITY DATA. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 CHLOR- DI- DP"' ENDO- PCB, ALDRIN. DANE, ODD, DOE, DDT, AZINON, ELORIN SULFAN. TIME TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UGIL) RIO GUAJATACA BASIN 50010790 - LAGO OE GUAJATACA NO.1 NEAR DAM NEAR QUEBRADILLASrPR (LAT 18°23'56" LONG 066°55'23") JUN , 1983 23... 1220 <.10 (.01 <.10 (.01 <.01 <.01 <.01 <.01 <.01 RIO GRANDE DE ARECIBO BASIN 50020050 - LAGO GARZAS NO.1 NEAR DAM NEAR AOJUNTAS,PR (LAT 18°03'21" LONG 066°44'35") JUN f 1933 23... 0335 <.10 <.01 <.10 (.01 <.01 <.01 <.01 <.01 <.01 50027090 - LAGO DOS BOCAS NO.1 NEAR DAM NEAR UTUADO,PR (LAT 18°20'09" LONG 066°40'04") JUN . 1983 22... 1300 <.10 (.01 <.10 <.01 <.01 (.01 <.01 (.01 <.01 RIO CE LA PLATA BASIN 53039950 - LAGO CARITE NO.1 NEAR DAM NEAR CAYEY.PR (LAT 13°04'39" LONG 066°06'19") JUN r 1983 27... 1140 <.10 <.01 <.10 <.01 <.01 (.01 <.01 <.01 <.01 50044950 LAGO LA PLATA NO.3 NEAR DAR NEAR NAR4NJITOr PR (LAT 18°20'18" LONG 066°14'01") JUN P 1733 21... 1340 <.10 <.01 <.10 <.01 <.01 C.01 <.01 <.01 <.01 RIO GRANDE DE LOIZA BASIN 50058300 - LAGO LOIZA NO.7 YEAR DAM NEAR TRUJILLO ALTOrPR (LAT 18°19'29" LONG 066°00'47") JUN 1983 24... 1045 <.10 <.01 <.10 (.01 <.01 (.01 0.03 <.01 <.01 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS 221 WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MALA- THION, TOTAL (UG/L) ENDRIN, ETHION, TOTAL TOTAL DATE (UG/L) (UG/L) HEPTA- CHLOR. TOTAL (UG/L) HEPTA- CHLOR EPDXIDE TOTAL (UG/L) LINDANE TOTAL (UG/L) METH- OXY- CHLOR, TOTAL (UG/L) METHYL PARA- THION. TOTAL (UG/L) METHYL TRI- THION. TOTAL (UG/L) MIREX, TOTAL (UG/L) RIO GUAJATACA BASIN--CONTINUED 50010790 - LAGO DE GUAJATACA' NO.1 NEAR DAM NEAR QUEBRADILLAS,PR (LAT 18°23'56" LONG 066°55'23") JUN 1983 23... <.01 50020050 <.01 <.01 <.01 <.01 <.01 <.01 <.01 <.01 <.01 RIO GRANDE DI ARECIBO BASIN-CONTINUED - LAGO GARZAS NO.1 NEAR DAM NEAR ADJUNTAS•PR (LAT 18°08'21" LONG 066°44'35") JUN • 1983 23... <.31 <.01 <.01 50027090 - LAGO DOS BOCAS ts JUN 1983 22... <.01 <.01 <.01 RIO 0 50039950 - LAGO CARITE JUN I 1933 27... <.01 <.01 <.01 <.01 <.01 <.01 (.01 <.01 <.01 (.01 3.1 NEAR DAM NEAR UTUADO,PR (LAT 13°20'09" LONG 065°40'04") <.01 <.01 <.01 <.01 <.01 (.01 <.01 LA PLATA BASIN--CONTINUED NO.1 NEAR DAM NEAR CAYEY.PR (LAT 18°04'39" LONG 066°06'19") <.01 (.01 <.01 (.01 <.01 <.01 <.01 50044950 - LAGO LA PLATA P3.3 NEAR DAM NEAR NARANJITO. PR (LAT 18°20'18" LONG 066°14'01") JUN r 1983 21... <.01 50058300 <.01 (.01 RIO G - LAGO LOIZA NO.7 <.01 <.01 <.01 <.01 <.01 <.01 <.01 ANDE DE LOIZA BASIN-CONTINUED NEAR DAM NEAR TRUJILLO ALTD,PR (LAT 18°19'29" LONG 066°00'47") JUN • 1983 24... <.01 <.01 <.01 <.01 (.01 <.01 (.01 <.01 <.01 <.01 222 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER-QUALITY DATA, WATER TEAR OCTOBER 1982 TO SEPTEMBER 1983 NAPH- THA- LINES, PARA- POLY- PER- TOX- TOTAL THION, CHLOR. THANE APHENEr TRI- 2,4-0P 2,4,5-T 2r 4-OP SILVEX. TOTAL TOTAL TOTAL TOTAL THION TOTAL TOTAL TOTAL TOTAL DATE (UG/L) (UG/L) (UG/L) (UG/L) (US/L) (UG/L) (UG/L) (UG/L) (UG/L) RIO GUAJATACA BASIN--CONTINJEO 50010790 - LAGO DE GUAJATACA NO.1 NEAR DAM NEAR QUEBRA)ILLAS,PR (LAT 13°23'56" LONG 066° 55'23") JUN P 1983 23... <.01 <.10 <.10 <1 <.31 .05 (.01 <.01 <.01 RIO GRANDE DE ARECIBO BASIN--CONTINUED 50020050 - LAGO GARZAS NO.1 NEAR DAM NEAR ADJUNTAS,PR (LAT 18°08'21" LONG 066°44'35") JUN P 1983 23... <.31 <.10 <.10 <1 (.01 <.01 (.01 <.01 <.01 50027090 LAGO DOS BOCAS NO.1 NEAR DAM NEAR UTUADO.PR (LAT 18° 20'09" LONG 066°40'04") JUN , 1983 22... <.01 <.10 (.10 <1 <. 01 <.01 <.01 <.01 (.01 RIO OE LA PLATA BASIN-CONTINUED 50039950 LAGO CARITE NO.1 NEAR DAM NEAR CAYEY.PR (LAT 13°04'39" LONG 066°06'19") JUN p 1983 27... <.01 <.10 (.10 <1 C.31 <.01 C.01 <.01 <.01 50044950 - LAGO LA PLATA NO.3 NEAR DAM NEAR NARANJITOr PR (LAT 18°20'18" LONG 066°14'31") JUN r 1933 21... (.01 <.10 <.10 <1 <.31 .01 C.01 <.01 <.01 RIO GRANDE DE LOIZA BASIN--CONTINUED 50058800 - LAGO LOIZA NO.7 NEAR DAM NEAR TRUJILLO ALTO,PR (LAT 18°19'29" LONG 066°03'47") JUN P 1983 24... (.01 <.10 (.10 <1 (.01 .08 (.01 <.01 <.01 223 ANALYSES OF SAMPLES OLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS QUALITATIVE AND ASSOCIATED QUANTITATIVE NALYSES OF BIOLOGICAL DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 PHYTOPLANKTON RIO GUAJATACA BASIN LAGO DE GUAJATACA NO. 3 NEAR MOUTH NEAR QUEBRADILLAS, PR (LAT 18°22'05" LONG 066°54' 36") 50010720 DATE TIME TOTAL CELLS/ML DIVERSITY: DIVISION .CLASS ..ORDER ...FAMILY ....GENUS ORGANISM BACILLARIOPHYTA (DIATO 5) .8ACILLARIOPHYCEAE ..ACHNANTHALES ...ACHNANTHACEAE ....ACHNANTHES ..EUPODISCALES ...COSCINOD/SCACEAE ....CYCLOTELLA ..NAVICULALES ...NAVICULACEAE ....NAVICULA CHLOROPHYTA (GREEN ALG E) .CHLOROPHYCEAE ..CHLOROCOCCALES ...CHLOROCOCCACEAE ....POLYEDRIOPSIS ...MICRACTINIACEAE ....MICRACTINIUM ...00CYSTACEAE ....ANKISTRODESMUS ....KIRCHNERIELLA ...SCENEDESMACEAE ....CRUCIGENIA ....SCENEDESMUS ....TETRASTRUM ..VOLVOCALES ...CHLAMYDOMONADACEAE ....CHLAMYDOMONAS ....CHLOROGONIUM CHRYSOPHYTA .CHRYSOPHYCEAE ..CHROMULINALES ...CHRYSOCOCCACEAE ....CHRYSOCOCCUS ..00HROMONADALES ...SYNURACEAE ....MALLOMONAS CRYPTOPHYTA (CRYPTOMON OS) .CRYPTOPHYCEAE ..CRYPTOMONADALES ...CRYPTOMONADACEAE ....CRYPTOMONAS DEC 9,82 FEB 23,83 JUN 23,83 1510 1340 1300 93000 6700 14000 0.1 1.9 1.8 0.1 1.9 1.8 0.1 2.4 2.8 0.1 2.5 3.0 0.1 2.6 3.2 CELLS PER- CELLS PER- CELLS PER­ /ML CENT /ML CENT /ML CENT 92000# 99 - 49 1 97 1 97 1 - 1100N 17 1900N 28 - 150 2 49 1 97 1 CYANOPHYTA (BLUE-GREEN ALGAE) .CYANOPHYCEAE ..CHROOCOCCALES ...CHROOCOCCACEAE ....ANACYSTIS - 1800# 28 ..NOSTOCALES ...NOSTOCACEAE ....APHANIZOMENON ..0SCILLATORIALES ...OSCILLATORIACEAE ....OSCILLATORIA EUGLENOPHYTA (EUGLENOI S ) .EUGLENOPHYCEAE ..EUGLENALES ...EUGLENACEAE ....EUGLENA - 340 5 ....TRACHELOMONAS 730 1 PYRRHDPHYTA (FIRE ALGAE) .DINOPHYCEAE ..DINOKONTAE ...PERIDINIACEAE ....PERIDINIUM 920 14 NOTE: A - DOMINANT ORGANISM; EQUAL TO OR GREATER THAN 15% 1400 10 170 1 87 1 610 4 87 1 350 3 350 3 350 3 520 4 610 4 700 5 45004 33 1700 13 1300 9 1000 8 * - OBSERVED ORGANISM, MAY NOT HAVE BEEN COUNTED; LESS THAN 1/2% 224 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS QUALITATIVE AND ASSOCIATED QUANTITATIVE ANALYSES OF BIOLOGICAL DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 PHYTOPLANKTON RIO GUAJATACA BASIN 50010790 LAGO DE GUAJATACA NO.1 NEAR DAM NEAR QUEBRADILLAS,PR (LAT 18°23'56" LONG 066°54'36") DATE DEC 9.82 FEB 23,83 JUN 23,83 TIME 1605 1445 1220 TOTAL CELLS/ML 80000 3100 14000 DIVERSITY: DIVISION 0.1 1.8 0.9 .CLASS 0.1 1.8 0.9 ..ORDER 0.1 2.0 1.9 ...FAMILY 0.1 2.2 2.7 ....GENUS 0.1 2.3 3.0 CELLS PER- CELLS PER- CELLS PER- ORGANISM /ML CENT /ML CENT /ML CENT BACILLARIOPHYTA (DIATOMS) .BACILLARIOPHYCEAE ..ACHNANTHALES ...AC4NANTHACEAE ....ACHNANTHES 80000# 99 290 2 ..EUPODISCALES ...COSCINODISCACEAE ....CYCLOTELLA 21 1 830 6 ..NAVICULALES ...NAVICULACEAE ....NAVICULA 490 4 CHLOROPHYTA (GREEN ALGAE) .CHLOROPHYCEAE ..CHLOROCOCCALES ...CHLOROCOCCACEAE ....TETRAEDRON 310 10 * 0 ...HYDRODICTYACEAE ....PED/ASTRUM 98 1 ...00CYSTACEAE ....ANKISTRODESMUS 730 1 150 1 ....KIRCHNERIELLA 63 2 ....00CYSTIS 190 6 ...PALMELLACEAE ....SPHAEROCYSTIS 4600# 34 ...SCENEDESMACEAE ....COELASTRUM 2700# 20 ....CRUCIGENIA 880 6 ....GLOEOACTINIUM - 490 4 ....SCENEOESMUS 42 1 - ..TETRASPORALES ...GLOEOCYSTACEAE ..GLOEOCYSTIS 1200 9 ..VOLVOCALES ...CHLAMYDOMONADACEAE ..CHLAMYDOMONAS 170 5 730 5 ..ZYGNEMATALES ...DESMIDIACEAE ....COSMARIUM * 0 ....STAURASTRUM * 0 CHRYSOPHYTA .CHRYSOPHYCEAE ..CHROMULINALES ...CHRYSOCOCCACEAE ....CHRYSOCOCCUS 210 7 CRYPTOPHYTA (CRYPTOMONADS) .CRYPTOPHYCEAE ..CRYPTOMONADALES ...CRYPTCMONADACEAE ....CRYPTOMONAS 98 1 CYANOPHYTA (BLUE-GREEN ALGAE) .CYANOPHYCEAE ..CHROOCOCCALES ...CHRDOCOCCACEAE ....ANACYSTIS 1400# 46 880 6 PYRRHOPHYTA (FIRE ALGAE) .DINOPHYCEAE ..DINOKONTAE ...PERIOINIACEAE ....PERIDINIUM 670# 21 * 0 NOTE: # - DOMINANT ORGANISM; EQUAL TO OR GREATER THAN 15% * OBSERVED ORGANISM, MAY NOT HAVE BEEN COUNTED; LESS THAN 1/2% 225 ANALYSES OF SAMPLES OLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS QUALITATIVE ANO ASSOCIATED QUANTITATIVE NALYSES OF BIOLOGICAL DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1933 PHYTOPLANKTON RIO GRANDE DE ARECIBO BASIN 50020050 LAGO GARZAS N .1 NR DAM NR ADJUNTAS,PR (LAT 18°08'21" LONG 066°44'35") DATE DEC 8,82 FEB 22.83 JUN 23.83 TIME 1315 1335 0835 TOTAL CELLS/ML 15000 4800 14000 DIVERSITY: DIVISION 0.9 1.4 1.6 .CLASS 0.9 1.4 1.6 ...ORDER 1.0 2.2 2.5 ...FAMILY 1.2 2.6 2.8 ....GENUS 1.2 2.7 2.8 CELLS PER- CELLS PER- CELLS PER- ORGANISM /ML CENT /ML CENT /ML CENT BACILLARIOPHYTA (DIATOM ) .3ACILLARIOPHYCEAE ..EUPODISCALES ...COSCINODISCACEAE ....CYCLOTELLA 200 1 1100 8 ....MELOSIRA -- 58 1 ..FRAGILARIALES ...FRAGILARIACEAE ....SYNEDRA 440 3 ..NAVICULALES ...NAVICULACEAE ....NAVICULA 3000# 22 CHLOROPHYTA (GREEN ALGAE) .CHLOROPHYCEAE ..CHAETOPHORALES ...CHAETOPHORACEAE ..ULVELLA 990 6 ..CHLOROCOCCALES ...CHLOROCOCCACEAE ....TETRAEORON 29 1 ...OICTYOSPHAERIACEAE ....DICTYOSPHAERIUM 820 5 940# 19 440 3 ...MICRACTINIACEAE ....GOLENKINIA 58 1 ...00CYSTACEAE ....ANKISTRODESmUS 150 1 58 1 2200# 16 ....CLOSTERIOPSIS * 0 - ....KIRCHNERIELLA 300 2 ....00CYSTIS * 0 ...SCENEDESMACEAE ....SCENEDESMUS 240 2 230 5 890 6 ..VOLVOCALES ...CHLAMYDOMONADACEAE ....CHLAMYDOMONAS * 0 560 12 780 6 ..ZYGNEMATALES ...DESMIDIACEAE ....COSMARIUM 640 13 780 6 ....STAURASTRUM 120 2 CHRYSOPHYTA .CHRYSOPHYCEAE ..CHROMULINALES ...CHRYSOCOCCACEAE ....CHRYSOCOCCUS 120 2 ..00HROMONADALES ...DINO3RYACEAE ....DINOBRYON 0 CRYPTOPHYTA (CRYPTOMON OS) .CRYPTOPHYCEAE ..CRYPTOMONADALES ...CRYPTOMONADACEAE ....CRYPTOMONAS * 0 29 1 110 1 CYANOPHYTA (BLUE-GREEN ALGAE) .CYANOPHYCEAE ..CHROOCOCCALES ...CHROOCOCCACEAE ....ANACYSTIS 12000# 81 18000 38 4C00# 29 EUGLENOPHYTA (EUGLENOI S) .EUGLENOPHYCEAE ..EUGLENALES ...EUGLENACEAE ....TRACHELOMONAS 93 1 29 1 PYRRHOPHYTA (FIRE ALGA:) .DINOPHYCEAE ..DINOKONTAE ...PERIDINIACEAE ....PERIDINIUM * 0 120 2 NOTE: # - DOMINANT ORG NISM; EQUAL TO OR GREATER THAN 15% * - OBSERVED ORG NISM, MAY NOT HAVE BEEN COUNTED; LESS THAN 1/2% 226 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS QUALITATIVE AND ASSOCIATED QUANTITATIVE ANALYSES OF BIOLOGICAL DATA. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 PHYTOPLANKTON RIO GRANDE DE ARECIBO BASIN 50025110 LAGO DOS BOCAS NO.3 AT WEST BRANCH NEAR UTUADO.PR (LAT 18°19'15" LONG 066° 40'11") DATE DEC 9,82 FEB 23.83 JUN 22.83 TIME 1045 0925 1345 TOTAL CELLS/ML 86000 64000 26000 DIVERSITY: DIVISION 0.5 1.1 1.5 .CLASS 0.5 1.1 1.5 ..ORDER 1.0 1.2 2.2 ...FAMILY 1.0 1.2 2.8 ....GENUS 1.8 1.2 2.9 CELLS PER- CELLS PER- CELLS PER- ORGANISM /ML CENT /ML CENT /ML CENT BACILLARIOPHYTA (DIATOMS) .BACILLARIOPHYCEAE ..BACILLARIALES ...NITZSCHIACEAE ....NITZSCHIA * ..EUPODISCALES ...COSCINODISCACEAE ....CYCLOTELLA * 0 2600 10 ..FRAGILARIALES ...FRAGILARIACEAE ....FRAGILARIA 2100 2 ....SYNEDRA 1100 1 150 1 CHLOROPHYTA (GREEN ALGAE) .CHLOROPHYCEAE ..CHLOROCOCCALES ...CHLOROCOCCACEAE ....SCHROEDERIA 590 2 ...DICTYOSPHAERIACEAE ....DICTYOSPHAERIUM 23000# 36 ...HYDRODICTYACEAE ....PEDIASTRUM 2900 3 ...MICRACTINIACEAE ....MICRACTINIUM 1800 7 ...00CYSTACEAE ....ANKISTRODESMUS 770 1 4800# 19 ....FRANCEIA 150 1 ....KIRCHNERIELLA 150 1 ....TREUBARIA 150 1 ...SCENEDESMACEAE ....SCENEDESMUS 2300 9 ..VOLVOCALES ...CHLAMYDOMONADACEAE ....CHLAMYDOMONAS 1000 2 1200 5 ..ZYGNEMATALES ...DESMIDIACEAE ....STAURASTRUM * 0 CHRYSOPHYTA .CHRYSOPMYCEAE ..00HROMONADALES ...00HROMONADACEAE ....00HROMONAS * 0 ...SYNURACEAE ...,MALLOMONAS * 0 CRYPTOPHYTA (CRYPTOMONADS) .CRYPTOPHYCEAE ..CRYPTOMONADALES ...CRYPTOMONADACEAE ....CRYPTOMONAS 150 1 CYANOPHYTA (BLUE-GREEN ALGAE) .CYANOPHYCEAE ..CHROOCOCCALES ...CHROOCOCCACEAE ....ANACYSTIS 43000# 56 39000# 60 5600# 22 ....GOMPHOSPHAERIA 22000# 26 ..NOSTOCALES ...NOSTOCACEAE ..APHANIZOMENON 3000 9 ..0SCILLATORIALES ...OSCILLATORIACEAE ....OSCILLATOR/A 5900# 23 PYRRHDPHYTA (FIRE ALGAE) .DINOPHYCEAE ..DINOKONTAE ...PERIDINIACEAE ....PERIDINIUM 1400 2 150 1 NOTE: 4 - DOMINANT ORGANISM; EQUAL TO OR GREATER THAN 15% * OBSERVED ORGANISM, MAY NOT HAVE BEEN COUNTED; LESS THAN 1/2% 227 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS QUALITATIVE AND ASSOCIATED QUANTITATIVE ANALYSES OF BIOLOGICAL DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 50027090 PHYTOPLANKTON RIO GRANDE DE ARECIBO BASIN LAGO DOS BOCAS NO.1 NEAR DAM NEAR UTUADOrPR (LAT 18°20'09" LONG 066°40'04") DATE DEC 9.82 FEB 23,83 JUN 22,83 TIME 0945 1000 1300 TOTAL CELLS/ML 170000 180000 77000 DIVERSITY: DIVISION 0.2 1.0 .CLASS 0.2 1.0 ..ORDER 0.5 1.3 ...FAMILY 0.5 1.4 ....GENUS 1.4 1.4 CELLS PER- CELLS PER- CELLS PER- ORGANISM /ML CENT /ML CENT /ML CENT BACILLARIOPHYTA (DIATOMS) .BACILLARIOPHYCEAE ..EUPODISCALES ...COSCINODISCACEAE ....CYCLOTELLA * 0 3500 5 ..FRAGILARIALES ...FRAGILARIACEAE ....FRAGILARIA * 0 -- ....SYNEDRA 3700 2 1100 1 * 0 CHLOROPHYTA (GREEN ALGAE) .CHLOROPHYCEAE ..CHLOROCOCCALES ...CHLORCCOCCACEAE ....SCHROEDERIA * 0 * 0 ...DICTYOSPHAERIACEAt ....DICTYOSPHAERIUM 61000# 34 ...MICRACTIN/ACEAE ....MICRACTINIUM leob 2 ...00CYSTACEAE ....ANKISTRODESMUS * 0 2200 3 ....KIRCHNERIELLA * 0 ....TREUBARIA * ...SCENEDESMACEAE ....SCENEOESMUS 3500 5 ..VOLVOCALES ...CHLAMYDOMONADACEAE ....CHLAHYD3MONAS * 0 1300 2 ..ZYGNEMATALES ...DESMIDIACEAE ....COSMARIUM * 0 ....STAURASTRUM * 0 CHRYSOPHYTA .CHRYSOPHYCEAE ..00HROMONADALES ...00HROMONADACEAE ....CCHRCMONAS * CRYPTOPHYTA (CRYPTOMONADS) .CRYPTOPHYCEAE ..CRYPTOMONADALES ...CRYPTOMONADACEAE ....CRYPTOMONAS 730 1 CYANOPHYTA (BLUE-GREEN ALGAE) .CYANOPHYCEAE ..CHROOCOCCALES ...CHROOCOCCACEAE ....ANACYSTIS 97000# 56 100000# 59 60000# 78 ..GOMPHOSPHAERIA 66000# 38 8800 5 ..NOSTOCALES ...NOSTOCACEAE ....APHANIZOMENON 5500 3 ..0SCILLATORIALES ...OSCILLATORIACEAE ....OSCILLATORIA 2200 3 EUGLENOPHYTA (EUGLENOIDS) .EUGLENOPHYCEAE ..EUGLENALES ...EUGLENACEAE ....TRACHELOMONAS * 0 PYRRHOPHYTA (FIRE ALGAE) .DINOPHYCEAE ..DINOKONTAE ...PERIDINIACEAE ....PERIDINIUM * C 830 1 NOTE: # - DOMINANT 1RGANISM: EQUAL TO OR GREATER THAN 15% * - OBSERVED RGANISM, MAY NOT HAVE BEEN COUNTED; LESS THAN 1/2% 228 ANALYSES 00 SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS QUALITATIVE AND ASSOCIATED QUANTITATIVE ANALYSES OF BIOLOGICAL DATA, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 PHYTOPLANKTON RIO DE LA PLATA BASIN 50039900 LAGO CARITE NO.3 ON RIO DE LA PLATA NEAR CAYEY, PR (LAT 18°05'04" LONG 066°06'03") DATE DEC 14,32 FEB 24,83 JUN 27,83 TIME 1205 1050 1215 TOTAL CELLS/ML 33000 7800 59000 DIVERSITY: DIVISION 0.6 1.2 0.4 .CLASS 0.6 1.2 0.4 ..ORDER 0.7 2.1 0.4 ...FAMILY 1.0 2.4 0.4 ....GENUS 1.0 2.4 0.4 CELLS PER- CELLS PER- CELLS PER- ORGANISM /ML CENT /ML CENT /ML CENT BACILLARIOPHYTA (DIATOMS) .BACILLARIOPHYCEAE ..EUPODISCALES ...COSCINODISCACEAE ....CYCLOTELLA 750 2 1100 15 ..FRAGILARIALES ...FRAGILARIACEAE ....SYNEDRA 1000 2 CHLOROPHYTA (GREEN ALGAE) .CHLOROPHYCEAE ..CHLOROCOCCALES ...DICTYOSPHAERIACEAE ....DICTYOSPHAERIUM 2000 6 440 6 ...00CYSTACEAE ....ANKISTRODESMUS -- - 55 1 550000 94 ....NEPHROCYTIUM 230001 34 - ....00CYSTIS -- - 30000 38 ..VOLVOCALES ...CHLAMYDOMONADACEAE ....CHLAMYOOMONAS 220 3 ..ZYGNEMATALES ...DESMIDIACEAE ....CLOSTERIUM 380 1 ....COSMARIUM 21000 27 ....STAURASTRUM 55 1 CHRYSOPHYTA .CHRYSOPMYCEAE ..CHROMULINALES ...CHRYSOCOCCACEAE ..CHRYSOCOCCUS 380 5 ..00HROMONADALES ...DINOBRYACEAE ....DINOBRYON 1500 5 ...SYNURACEAE ....MALLOMONAS 55 1 520 1 CYANOPHYTA (BLUE-GREEN ALGAE) .CYANOPHYCEAE ..CHROOCOCCALES ...CHROOCOCCACEAE ....ANACYSTIS 2100 4 EUGLENOPHYTA (EUGLENOIDS) .EUGLENOPHYCEAF ..EUGLENALES ...EUGLENACEAE ....TRACHELOMONAS 55 1 PYRRHOPHYTA (FIRE ALGAE) .DINOPHYCEAE ..DINOKONTAE ...PERIDINIACEAE ....PERIDINIUM 680 2 380 5 NOTE: A - DOMINANT ORGANISM; EQUAL TO OR GREATER THAN 15% - OBSERVED ORGANISM, MAY NOT HAVE BEEN COUNTED; LESS THAN 1/2% 5300# 20 480 2 16000# 60 550 2 270 1 290 5 1100# 19 44000# 90 490 9 860 2 140 1 1300# 24 -- 98 2 229 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS QUALITATIVE AND ASSOCIATED QUANTITATIVE ANALYSES OF BIOLOGICAL DATA, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 PHYTOPLANKTON RIO DE LA PLATA BASIN 50039950 LAGO CARITE NO.1 NEAR DAM NEAR CAYEY,PR (LAT 18°04'39" LONG 066°06'19") DATE DEC 14,82 FEB 24,83 JUN 27,83 TIME 1130 1040 1140 TOTAL CELLS/ML 26000 5700 48000 DIVERSITY: DIVISION 0.7 1.6 0.4 .CLASS 0.7 1.6 0.4 ..ORDER 0.7 2.4 0.6 ...FAMILY 1.6 2.6 0.6 ....GENUS 1.7 2.7 0.6 CELLS PER- CELLS PER- CELLS PER- ORGANISM /ML CENT /ML CENT /ML CENT BACILLARIOPHYTA (DIATOMS) .BACILLARIOPHYCEAE ..ACHNANTHALES ...ACHNANTHACEAE ..EUPODISCALES ...COSCINOOISCACEAE ..CYCLOTELLA ..FRAGILARIALES ...FRAGILARIACEAE ....SYNEDRA CHLOROPHYTA (GREEN ALGAE) .CHLOROPHYCEAE ..CHLOROCOCCALES ...COCCOMYXACEAE ....ELAKATOTHRIX ...DICTYOSPHAERIACEAE ....DICTYOSPHAERIUM ...00CYSTACEAE ....ANKISTRODESMUS ....NEPHROCYTIUM ....00CYSTIS ...SCENEDESMACEAE ....GLOEOACTINIUM ..VOLVOCALES ...CHLAMYDOMONAOACEAE ....CHLAMYDOMONAS ..ZYGNEMATALES ...DESMIDIACEAE ....COSMARIUM ....STAURASTRUM CHRYSOPHYTA .CHRYSOPHYCEAE ..00HROMONADALES ...DINOBRYACEAE ....DINOBRYON tYANOPHYTA (BLUE-GREEA ALGAE) .CYANOPHYCEAE ..CHROOCOCCALES ...CHROOCOCCACEAE ....ANACYSTIS EUGLENOPHYTA (EUGLENOIDS) .EUGLENOPHYCEAE ..EUGLENALES ...EUGLENACEAE ....EUGLENA ....TRACHELOMONAS PYRRHOPHYTA (FIRE ALGAE) .DINOPHYCEAE ..DINOKONTAE ...PERIDINIACEAE ....PERIDINIUM 33 1 200 1 550 10 430 1 3100 12 1500# 26 3500 7 33 1 33 1 200 1 230 4 NOTE: # - DOMINANT ORGANISM; EQUAL TO OR GREATER THAN 15% * OBSERVED ORGANISM, MAY NOT HAVE BEEN COUNTED; LESS THAN 1/2% 230 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS QUALITATIVE AND ASSOCIATED QUANTITATIVE ANALYSES OF BIOLOGICAL DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 PHYTOPLANKTON RIO DE LA PLATA BASIN 50044400 LAGO LA PLATA NO.5 NEAR MOUTH NEAR NARANJITO, PR (LAT 18°19'33" LONG 066°12'28") DATE DEC 7,82 FEB 13,83 JUN 21,33 TIME 1145 1100 1145 TOTAL CELLS/ML 1100 7900 3100 DIVERSITY: DIVISION 0.9 0.5 1.6 .CLASS 0.9 0.5 1.6 ..ORDER 1.1 1.0 1.9 ...FAMILY 1.1 1.0 1.9 ....GENUS 1.1 1.0 2.4 CELLS PER- CELLS PER- CELLS PER- ORGANISM /ML CENT /ML CENT /ML CENT BACILLARIOPHYTA (DIATOMS) .BACILLARIOPHYCEAE ..ACHNANTHALES ...ACHNANTHACEAE ....COCCONEIS 29 1 ..EUPODISCALES ...COSCINODISCACEAE ....CYCLOTELLA 3004 27 65000 32 6204 20 ....MELOSIRA - 29 1 ..FRAGILARIALES ...FRAGILARIACEAE ....SYNEDRA 530 7 59 2 ..NAVICULALES ...NAVICULACEAE ....NAVICULA 45 4 CHLOROPHYTA (GREEN ALGAE) .CHLOROPHYCEAE ..CHLOROCOCCALES ...MICRACTINIACEAE ....GOLENKINIA 600 8 ...00CYSTACEAE ....ANKISTRODESMUS - - 7404 24 ....KIRCHNERIELLA 29 1 ..VOLVOCALES ...CHLAMYDOMONADACEAE ....CHLAMYDOMONAS 7704 69 300 4 150 5 CYANOPHYTA (BLUE-GREEN ALGAE) .CYANOPHYCEAE ..CHROOCOCCALES ...CHROOCOCCACEAE ....ANACYSTIS 11004 35 ....COCCOCHLORIS 320 11 EUGLENOPHYTA (EUGLENOIDS) .EUGLENOPHYCEAE ..EUGLENALES ...EUGLENACEAE ....EUGLENA 29 1 NOTE: 4 - DOMINANT ORGANISM; EQUAL TO OR GREATER THAN 15% - OBSERVED ORGANISM, MAY NOT HAVE BEEN COUNTED; LESS THAN 1/2% 231 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS QUALITATIVE AND ASSOCIATED QUANTITATIVE ANALYSES OF BIOLOGICAL DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 PHYTOPLANKTON RIO DE LA PLATA BASIN 50044950 LAGO LA PLATA NO.3 NEAR DAM NEAR NARANJITO. PR (LAT 18°20'18" LONG 066° 14'01") DATE DEC 7,82 FEB 18.83 JUN 21,83 TIME 1045 1220 1040 TOTAL CELLS/ML 13000 9200 37000 DIVERSITY: DIVISION 0.5 0.6 1.5 .CLASS 0.5 0.6 1.5 ..ORDER 0.5 1.2 1.6 ...FAMILY 0.5 1.2 1.6 ....GENUS 0.5 1.4 1.6 CELLS PER- CELLS PER- CELLS PER- ORGANISM /ML CENT /ML CENT /ML CENT BACILLARIOPHYTA (DIATOMS) .BACILLARIOPHYCEAE ..EPITHEMIALES ...EPITHEMIACEAE ....EPITHEMIA 600 7 ..EUPODISCALES ...COSCINODISCACEAE ....CYCLOTELLA 11000# 37 6800# 73 16000# 44 ..FRAGILARIALES ...FRAGILARIACEAE ....SYNEDRA 380 4 CHLOROPHYTA (GREEN ALGAE) .CHLOROPHYCEAE ..CHLOROCOCCALES ...MICRACTINIACEAE ....GOLENKINIA 930 11 ....MICRACTINIUM 530 6 ...00CYSTACEAE ....ANKISTRODESMUS 910 2 ..VOLVOCALES ...CHLAMYDOMONADACEAE ....CHLAMYDOMONAS 1600 13 2400 7 CRYPTOPHYTA (CRYPTOMONADS) .CRYPTOPHYCEAE ..CRYPTOMONADALES ...CRYPTOMONAOACEAE ....CRYPTOMONAS 1200 3 CYANOPHYTA (BLUE-GREEN ALGAE) .CYANOPHYCEAE ..CHROOCOCCALES ...CHROOCOCCACEAE ....ANACYSTIS 160000 44 NOTE: # - DOMINANT ORGANISM; EQUAL TO OR GREATER THAN 15% * - OBSERVED ORGANISM, MAY NOT HAVE BEEN COUNTED; LESS THAN 1/2% 232 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PART/AL-RECORD STATIONS QUALITATIVE AND ASSOCIATED QUANTITATIVE ANALYSES OF BIOLOGICAL DATA, WATER YEAR OCTOBER 19B2 TO SEPTEMBER 1983 PHYTOPLANKTON RIO GRANDE DE LOIZA BASIN 50057500 LAGO LOIZA NO.4 NEAR MOUTH NEAR CAGUAS, PR (LAT 18°16'51" LONG 066°00'35") DATE DEC 10,82 FEB 17,83 JUN 24,83 TIME 1150 1315 1115 TOTAL CELLS/ML 16000 5500 2600 DIVERSITY: DIVISION 0.9 1.1 1.6 .CLASS 0.9 1.1 1.6 ..ORDER 1.0 1.1 2.0 ...FAMILY 1.1 1.1 2.1 ....GENUS 1.1 1.1 2.2 CELLS PER- CELLS PER- CELLS PER- ORGANISM /ML CENT /ML CENT /ML CENT BACILLARIOPHYTA (DIATOMS) .BACILLARIOPHYCEAE ..EUPODISCALES ...COSCINODISCACEAE ....CYCLOTELLA 13000# 31 4200M 76 160 6 CHLOROPHYTA (GREEN ALGAE) .CHLOROPHYCEAE ..CHLOROCOCCALES ...DICTYOSPHAERIACEAE ....OICTYOSPHAERIUM 560 3 ...MICRACTINIACEAE ....MICRACTINIUM 360 7 ...00CYSTACEAE ....ANKISTRODESMUS 73 3 ....KIRCHNERIELLA 700 4 59 2 ....00CYSTIS 420 3 ...SCENEDESMACEAE ....SCENEOESMUS 180 7 ..VOLVOCALES ...CHLAMYOOMONADACEAE ....CHLAMYDOMONAS 220 2 980# 38 CHRYSOPHYTA .CHRYSOPHYCEAE ..00HROMONADALES ...00HROMONADACEAE ....00HROMONAS 29 1 CYANOPHYTA (BLUE-GREEN ALGAE) .CYANOPHYCEAE ..CHROOCOCCALES .:.CHROOCOCCACEAE ....ANACYSTIS 1100 7 800 15 970$ 38 EUGLENOPHYTA (EUGLENOIDS) .EUGLENOPHYCEAE ..EUGLENALES ...EUGLENACEAE ....EUGLENA 73 3 ....TRACHELOMONAS 44 2 PYRRHOPHYTA (FIRE ALGAE) .0INOPHYCEAE ..DINOKONTAE ...PERIDINIACEAE ....PERIDINIUM 130 2 NOTE: # - DOMINANT ORGANISM; EQUAL TO OR GREATER THAN 15% * - OBSERVED ORGANISM, MAY NOT HAVE BEEN COUNTED; LESS THAN 1/2% 233 ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS QUALITATIVE AND ASSOCIATED QUANTITATIVE ANALYSES OF BIOLOGICAL DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 PHYTOPLANKTON RIO GRANDE DE LOIZA BASIN 50058800 LAGO LOIZA NO.7 NEAR DAM NEAR TRUJILLO ALTO. PR (LAT 18°20'18" LONG 066°00'47") DATE DEC 10,82 FEB 17,83 JUN 24,83 TIME 1105 1210 1045 TOTAL CELLS/ML 47000 12000 26000 DIVERSITY: DIVISION 1.3 0.0 1.1 .CLASS 1.3 0.0 1.1 ..ORDER 1.7 0.0 1.2 ...FAMILY 1.8 0.0 1.3 ....GENUS 1.8 0.0 2.1 CELLS PER- CELLS PER- CELLS PER- ORGANISM /ML CENT /ML CENT /ML CENT BACILLARIOPHYTA (DIATOMS) .BACILLARIOPHYCEAE ..EUPODISCALES ...COSCINODISCACEAE ....CYCLOTELLA 24000# 50 12000#100 5100# 20 ....MELOS/RA 460 2 ..NAVICULALES ...NAVICULACEAE ....NAVICULA 290 1 CHLOROPHYTA (GREEN ALGAE) .CHLOROPHYCEAE ..CHLOROCOCCALES ...CHLOROCOCCACEAE ....SCHROEDERIA 860 2 ...DICTYOSPHAERIACEAE ....DICTYOSPHAERIUM 910 4 ...00CYSTACEAE ....ANKISTROOESMUS 570 1 * 0 ..KIRCHNERIELLA 460 2 ..VOLVOCALES ...CHLAMYDOMONADACEAE ....CHLAMYDOMONAS 690 3 CRYPTOPHYTA (CRYPTOMONADS) .CRYPTOPHYCEAE ..CRYPTOMONADALES ...CRYPTOMONADACEAE ....CRYPTOMONAS 290 1 CYANOPHYTA (BLUE-GREEN ALGAE) .CYANOPHYCEAE ..CHROOCOCCALES ...CHROOCOCCACEAE ....AGMENELLUM 10000# 39 ....ANACYSTIS 13000# 27 8000# 31 ..OSCILLATORIALES ...OSCILLATORIACEAE ....LYNGBYA 8300# 18 EUGLENOPHYTA (EUGLENOIDS) .EUGLENOPHYCEAE ..EUGLENALES ...EUGLENACEAE ....TRACHELOMONAS 290 1 NOTE: N - DOMINANT ORGANISM; EQUAL TO OR GREATER THAN 15% * - OBSERVED ORGANISM, MAY NOT HAVE BEEN COUNTED; LESS THAN 1/2% 234 ANALYSES OF SAMPLES COLLECTED AT MISCELLANEOUS SITES Samples are collected at sites other than gaging stations and partial-record stations to give better areal coverage in a river basin. Such sites are to be referred to as miscellaneous sites. WATER-OUALILTY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 COLI- STREP- SPE- FORM, TOCOCCI MAGNE- SODIUM STREAM- CIFIC FECAL. FECAL. HARD- CALCIUM SIUM, SODIUM. AD- FLOW, CON- PH 0.7 KF AGAR NESS DIS- DIS- DIS- SORP- INSTAN- DUCT- (STAND- TEMPER- UM-MF (COLS. (MG/L SOLVED SOLVED SOLVED TION TIME TANEOUS ANCE ARO ATURE (COLS./ PER AS (MG/L (MG/L (MG/L RATIO GATE (CFS) (UMHOS) UNITS) (DEG C) 100 ML) 100 ML) CAC03) AS CA) AS MG) AS NA) RIO GRANDE DE ARECIBO BASIN 50021500 - RIO PELLEJAS NEAR UTUADO. PR (LAT 18°13'53" LONG 066°42'56") JAN , 1933 17... 1545 5800 K1500 50028400 - RIO TANAMA AT CHARCO HONDO. PR (LAT 18°24'52" LONG 066°42'52") JUN , 1933 23... 1120 39 287 7.8 25.5 140 51 3.7 6.6 .3 RIO GRANDE DE LOI2A BASIN 50051310 - RIO CAYAGUAS AT CERRO GORDO. PR (LAT 18°09'27" LONG 065°57'29") APR 1983 21... 1600 E102 115 21... 1605 E102 -- RIO BLANCO BASIN 50076000 - RIO BLANCO NEAR FLORIDA, PR (LAT 18 °13'45" LONG 065°47'06") APR , 1933 21... 1125 E269 65 23.5 21... 1320 E234 68 23.5 21... 1325 E233 68 23.5 -- 21... 1430 203 68 23.5 16 4.2 1.4 6.2 .7 50076600 - RIO BLANCO AT RIO BLANCO PUMP HOUSE, PR (LAT 18 °13'19" LONG 065°47'05") SEP 1933 21... 1315 139 7.8 27.0 41 10 3.8 9.9 .7 50077500 - RIO BLANCO AT NAGUASO, PR (LAT 18°12'16" LONG 065°45'31") SEP 1983 15... 1330 146 7.0 29.5 46 12 3.8 10 .7 E estimate K = non-ideal count ANALYSES OF SAMPLES COLLECTED AT MISCELLANEOUS SITES WATER-QUALILTY DATA•1 WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 SOLIDS, POTAS- ALKA- CHLO7 FLUO- SILICA, SUM OF SOLIDS, MANUA- SIUM, LINITY SULFATE RIDE, RIDE, DIS- CONSTI- DIS"' IRON, NESE, SEDI- DIS- FIELD DIS- DIS- DIS- SOLVED TUENTS, SOLVED DIS- DIS- MENT, SOLVED (MG/L SOLVED SOLVED SOLVED (MG/L DIS- (TONS SOLVED SOLVED SUS-. (MG/L AS (MG/L (MG/L 1 (MG/L AS SOLVED PER (UG/L (UG/L PENDED DATE AS K) CAC03) AS SO4) AS CL) AS F) SI02) (MG/L) DAY) AS FE) AS MN) (MG/L) RIO GRANDE DE ARECIBO BASIN--CONTINUED 50021500 - RIO PELLEJAS NEAR UTUADO, PR (LAT 18°13'53" LONG 066°42'56") JAN 1933 17... 50028400 - RIO TANAMA1 AT CHARCO HONDO, PR (LAT 18°24'52" LONG 066°42'52") JUN 1983 23... 1.0 110 7.8 8.8 .20 10 155 16.3 5 5 RIO GRANIDE DE LOIZA BASIN-CONTINUED 50051310 - RIO CAYAGUAS AT CERRO GORDO, PR (tAT 18°09'27" LONG 065°57'29") APR , 1983 21... 260 21... 260 RIO 4LANCO BASIN--CONTINUED 50076000 - RIO BLANCO NEAR FLORIDA, PR (LAT 18°13'45" LONG 065°47'06") 235 APR , 1983 21... 21... 21... 21... .7 1- 9.6 8.3 <.10 13 52 28.4 97 185 97 50076600 - RIO BLANCO AI RIO BLANCO PUMP HOUSE, PR (LAT 18°13'19" LONG 065°47'05") SEP , 1983 21... 1.0 43 4.4 16 .10 24 95 50077500 - RIO BUNCO AT NAGUABO, PR (LAT 18°12'16" LONG 065°45'31") SEP , 1983 15... 1.2 49 5.4 12 1 <.10 24 98 237 k N.) co 67° 5' 67°00' 45' 30' 15' 66700' 45' 65°30' OCEANO ATLANTICO .0 le 0 %,0 0 v0 JGO e 420' ) e ,,,0 e Ota e- AO° IP e e c ,0 t\otp 168 .1/0 4 vie 8. 1 .,se 000 et`b, 0 18°30' 1 \C; .0 +0 es 135. 69 7 • I 4p ez' o .164 66 fti• 110 Quo ito / , Rio Culebrinas • 165 161 711 68 1550 150 g;o s. 6 (t* g o Rio Guayabo gl1/` 4 6 Rio Grand 58 83 1421 Rio Fajardo Rio Grande 15 de Afiasco 521 45 Rio Yaguez Rfo Daguao .123 86 43 \ Quebrada Palma Rio Guanajibo • 7 , \ Rio Santiago Rio Bianco 147 138 33 0 Rio Anton Ruiz 144 31 87 Rio Humacao 95 7 918 Rio Guayands • 8 96 • 143 13 4 18.00' • • 124 2 8/ I , , • I.' , ks 44) Ob & 0A . 1% I, V v000 "24002',4,01‘Aleforev,c,t2' ,te 45 eGo vk P '§ 04eV 4,1*S J ,.,y 1/40 V co 0,00 1/40 6 1/0 4 \o 443 0‘\0 'CII. i1\/4°<at oi' \* leoe 0° q, 1%0 i, it. Is 0 iii. k 0 i 0 1/4 AO . 0 AO q. 1/40 •41) e i, s'ik p * EXPLANATION Ck‘ sk‘ - x-sz,, e v148 146 l' q• to I SO 0 1/40 GROUND WATER STATIONS 17°45' - 0 1,0 20 30 KILOMETERS 115 WELL AND WELL NUMBER 0 10 20 MILLS MAR CARIBE ► ► Figure 26.--Ground-water stations in Puerto Rico. 239 GROUND-WATER LEVELS RIO GUAJATACA BASIN 182538067015900. Local number, 164. LOCATION.--Lat 18°25'38", long 67°01'59". Owner: P.R. Aqueduct and Sewer Authority. Name: Rocha Moca. AQUIFER.--Aymamen Limestone. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 12 in (0.30 m), cased 0-100 ft (0-30.49 m), perforated 100-160 ft (30.49-48.78 m), diameter 10 in (0.25 m), cased 0-140 ft (0-42.68 m), perforated 140-200 ft (42.68-61.0 m), gravel packed 120-200 ft (36.58-61.0 m). Depth 200 ft (61.0 m). DATUM.--Altitude of land-surface datum is 787.2 ft (240 m) above mean sea level. Measuring point: Upper edge of 1.5 in (0.04 m) pipe on pump base, 1.40 ft (0.43 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--January 18, 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 147.1 ft (44.85 m) below land-surface datum, May 24, 1982; lowest water level measured, 176.1 ft (53.69 m) below land-surface datum, Feb. 18, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Jan. 18, 1982 173.6 July 26, 1982 147.5 Dec. 16, 1982 148.5 May 18, 1983 159.1 Feb. 18 176.1 Aug. 18 147.8 Jan. 12, 1983 147.7 June 28 163.9 Mar. 18 147.2 Sept. 9 147.7 Feb. 2 148.6 July 18 a155.3 Apr. 16 147.6 Oct. 8 147.7 Mar. 4 148.5 Aug. 22 a147.8 May 24 147.1 Nov. 8 147.1 Apr. 6 163.0 Sept. 12 a148.2 June 18 152.2 182422067015100. Local number, 165. LOCATION.--Lat 18°24'22", long 67°01'51". Owner: P.R. Aqueduct and Sewer Authority. Name: Mateo Perez - Bo. Saltos. AQUIFER.--Cibao Formation, Guajataca member. WELL CHARACTERISTICS.--Drilled production water-table well, diameter 16 in (0.40 m), cased 16 in (0.40 m) 0-40 ft (0-12.2 m), cased 12 in (0.30 m) 40-200 ft (12.2-61.0 m). Depth 200 ft (61.0 m). DATUM: Altitude of land-surface datum is about 672.4 ft (205 m) above mean sea level. Measuring point: Hole on top of pump base, 1.00 ft (0.30 in) above land-surface datum. REMARKS.--Pumping discontinued. Abandoned observation well. PERIOD OF RECORD.--January 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 69.22 ft (21.1 m) below land-surface datum, Nov. 8, 1982; lowest water level measured, 70.60 ft (21.5 m) below land-surface datum, June 18, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Jan. 18, 1982 69.83 July 26, 1982 69.35 Dec. 16, 1982 69.84 May 18, 1983 69.55 Feb. 18 69.86 Aug. 18 69.82 Jan. 12, 1983 69.74 June 28 69.55 Mar. 18 69.97 Sept. 9 69.85 Feb. 69.90 July 18 69.60 Apr. 16 70.56 Oct. 8 69.47 Mar. 69.85 Aug. 22 69.60 May 24 69.65 Nov. 8 69.22 Apr. 70.10 Sept. 12 69.48 June 18 70.60 a Pumping. 240 GROUND-WATER LEVELS RIO GRANDE DE ARECIBO BASIN 181038066441201. Local number, 86. LOCATION.--Lat 18°10'38", long 66°44'12". Owner: Joaquin Mattei - U.S. Geological Survey. Name: Adjuntas. AQUIFER.--Alluvium of Quaternary Age and volcanic rock of Eocene Age. WELL CHARACTERISTICS.--Drilled test well, diameter 6 in (15 cm). Depth 300 ft (91.4 m). DATUM.--Altitude of land-surface datum is about 1,460 ft (445.0 m) above mean sea level. Measuring point: Bottom edge of hole in 6 in (15 cm) casing, 1.45 ft (0.44 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--August 1967 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 4.34 ft (1.32 m) below land-surface datum, Jan. 12, 1979; lowest measured, 12.53 ft (3.82 m) below land-surface datum, Apr. 12, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 4 10.86 Feb. 7 12.00 May 11 11.80 Aug. 22 11.35 Nov. 9 10.91 Mar. 16 11.92 June 22 10.84 Sept. 6 12.07 Jan. 24 11.80 Apr. 12 12.53 Aug. 2 11.80 181307066355001. Local number, 123. LOCATION.--Lat 18°13'07", long 66°35'50". Owner: P.R. Aqueduct & Sewer Authority. Name: Jayuya 3. AQUIFER.--Recent alluvium. WELL CHARACTERISTICS.--Drilled for public supply well, diameter 10 in (25 cm) 0-27 ft (0-8.2 m), 10 in (25 cm) 27-100 ft (8.2- 33.5 m) perforated and all gravel packed. DATUM.--Altitude of land-surface datum is about 1,400 ft (427 m) above mean sea level. Measuring point: Lower edge 0.75 in (1.90 cm) pipe on concrete pump base, 1.40 ft (0.43 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--January 15, 1976 to July 21, 1977, discontinued. January 15, 1980 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 10.73 ft (3.27 m) below land-surface datum, May 30, 1980; lowest measured, a49.36 ft (a15.04 m) below land-surface datum, Apr. 21, 1976. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 4 14.57 Jan. 24 15.05 Apr. 12 14.89 June 5 14.46 Nov. 9 14.21 Mar. 16 12.76 May 11 14.43 Aug. 22 14.87 Sept. 6 15.25 182632066384800. Local number, 161. LOCATION.--Lat 18°26'32", long 66°38'48". Owner: P.R. Aqueduct and Sewer Authority. Name: Santana #2 AQUIFER.--AymamOn Limestone. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 12 in (0.30 m), cased 0-180 ft (0-54.88 m), diameter 10 in (0.25 m), perforated 175-220 ft (53.35-67.07 m). Depth 220 ft (67.07 m). DATUM.--Altitude of land-surface datum is about 148 ft (45 m) above mean sea level. Measuring point: Airhole in pump base, 0.90 ft (0.27 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--January 8, 1982 to current year. EXTREMES FOR PERIOD OF,RECORD.--Highest water level measured, a113.7 ft (34.66 m) below land-surface datum, Jan. 8, 1982; lowest water level measured, a152.2 ft (46.40 m) below land-surface datum, May 12, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Jan. 8, 1982 a113.7 June 17, 1982 a130.5 Nov. 5, 1982 a135.9 Apr. 6, 1984 117.4 Feb. 17 a130.1 July 26 a142.8 Dec. 15 a128.4 May 12 a152.2 Mar. 18 a122.7 Aug. 19 a136.8 Jan. 13 a129.6 July 18 a151.3 Apr. 15 a139.7 Sept. 10 al40.2 Feb. 2 a132.0 Aug. 19 139.8 May 21 a134.9 Oct. 8 a146.6 Mar. 7 a128.3 Sept. 12 a148.4 a Pumping. 241 GROUND-WATER LEVELS RIO GRANDE DE MANATI BASIN 182548066300201. Local number, 68. LOCATION.--Lat 18°25'48", long 66°30'02". Owner: P.R. Aqueduct and Sewer Authority. Name: Manati 2. AQUIFER.--Unconsolidated deposits of Quaternary Age and limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 20 to 12 in (51 to 30 cm), cased 20 in (51 cm) 8-168 ft (2.4-51.2 m) 12 in (30 cm) 153-206 ft (46.6-62.8 m); perforated 20 in (51 cm) 80-168 ft (24.4-51.2 m)', 12 in (30 cm), 153-206 ft (46.6-62.8 m). Depth 212 ft (64.6 m). DATUM.--Altitude of land-surface datum is 31.41 ft (9.574 m) above mean sea level. Measuring point: Bottom edge of hole in 20 in (51 cm) casing, 3.55 ft (1.08 m) above land-surface datum. REMARKS.--Observation well. Lowest and highest water levels are pumping levels. PERIOD OF RECORD.--October 1960 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, a22.50 ft (a6.86 m) below land-surface datum, June 2, 1965; lowest measured, a37.19 ft (a11.34 m) below land-surface datum, Jan. 15, 1975. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Date Water level Date Water level Date Water level Date Water level Oct. 8 Nov. 5 Dec. 13 a28.92 a29.09 a29.19 Jan. 13 Feb. 2 Mar. 7 a28.68 a29.36 a29.38 Apr. 5 May 12 June 27 a29.80 a26.40 a29.04 July 18 Aug. 22 Sept. 12 a29.10 a29.30 a29.38 182603066333601. Local number, 71. LOCATION.--Lat 18°26'03", long 66°33'36". Owner: P.R. Aqueduct and Sewer Authority. Name: Florida Afuera, Barceloneta. AQUIFER.--Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 12 in (30 cm), cased 0-150 ft (0-45.7 m). Depth 235 ft (71.6 m) DATUM.--Altitude of land-surface datum is about 213 ft (64.9 m) above mean sea level. Measuring point: Lower edge of 0.75 in (1.9 cm) pipe in pump base, 3.0 ft (0.91 m) above land surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--March 1960 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, a17.60 ft (a5.36 m) below land-surface datum, June 28, 1983; lowest measured, 226.9 ft (69.2 m) below land-surface datum, Apr. 4, 1963. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 8 a25.58 Jan. 13 a21.77 Apr. 6 a23.52 July 18 a20.55 Nov. 5 a24.56 Feb. 3 a22.10 May 10 a22.00 Aug. 19 al9.20 Dec. 5 a22.88 Mar. 3 a24.70 June 28 a17.60 Sept. 12 al9.09 a Pumping. 242 GROUND-WATER LEVELS RIO GRANDE DE MANATI BASIN 182621066343301. Local number, 135. LOCATION.--Lat 18°26'21", long 66°34'33". Owner: Puerto Rico Land Authority. Name: Lederle. AQUIFER.--Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled agricultural water-table well, diameter 24 in (61 cm), cased 0-30 ft (0-9.1 m), diameter 16 5/8 in (42 cm), cased to 0-450 ft (0-137.2 m). Depth 550 ft (167 6 m). DATUM.--Altitude of land-surface datum is 287.00 ft (87.48 m) above mean sea level. Measuring point: Top of shelter floor, 2.8 ft (0.85 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.--November 1979 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level, 276.85 ft (84.38 m) below land-surface datum, Dec. 16, 1981; lowest, 283.7 ft (86.47 m) below land-surface datum, Nov. 1, 1978. WATER LEVEL. IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 283.10 283.22 283.23 283.43 283.37 283.42 283.42 283.17 283.36 283.37 283.38 2 283.10 283.30 283.24 283.42 283.38 283.39 283.46 283.21 283.35 283.38 283.38 3 283.10 283.30 283.24 283.42 283.42 283.39 283.46 283.23 283.35 283.40 283.39 4 283.09 283.28 283.24 283.43 283.43 283.45 283.46 283.25 283.34 283.41 283.39 5 283.12 283.30 283.24 283.46 233.47 283.46 283.46 283.31 283.32 283.42 283.38 6 283.13 283.26 283.27 283.46 283.47 283.46 283.46 283.29 283.31 283.46 283.35 7 283.13 283.23 283.27 283.46 283.47 283.46 --- 283.31 283.30 283.46 283.26 8 283.13 283.22 283.27 283.47 283.48 283.46 283.34 283.22 283.46 283.25 9 283.12 283.21 283.27 283.47 283.48 283.46 283.34 283.22 283.43 283.25 10 283.09 283.18 233.27 283.47 283.47 283.45 283.35 283.23 283.41 283.27 11 283.07 283.17 283.23 283.47 283.47 283.44 283.37 283.35 283.30 283.41 283.28 12 --- 283.03 248.99 283.30 233.47 233.46 283.41 283.36 283.35 283.30 283.41 283.35 13 282.99 283.01 283.19 283.31 283.47 283.45 283.37 283.35 283.35 283.31 283.41 283.38 14 282.99 283.00 283.20 283.31 283.48 283.45 283.34 283.33 283.35 283.34 283.41 283.39 15 282.99 283.00 283.23 283.32 283.47 233.46 283.34 283.31 283.35 283.34 283.41 283.39 16 282.99 283.03 283.28 283.32 283.47 233.43 283.36 283.30 283.35 283.31 283.40 283.39 17 282.99 283.03 283.30 283.32 283.46 283.35 283.33 283.23 283.34 233.22 283.40 283.38 18 283.01 283.03 283.30 283.34 283.43 283.32 283.31 283.20 283.32 283.21 283.41 283.37 19 283.02 283.04 283.30 283.37 283.42 283.31 283.31 283.17 283.31 283.21 283.40 283.35 20 283.03 283.04 283.33 283.40 283.36 283.32 283.32 283.15 283.30 283.24 283.42 283.33 21 283.04 283.03 283.33 283.42 283.35 233.34 283.31 283.15 283.28 283.34 283.43 283.34 22 283.05 283.04 283.33 283.42 283.42 283.36 283.28 283.17 283.23 283.36 283.40 283.25 23 283.08 283.10 283.33 283.41 283.45 283.37 283.25 283.17 283.23 283.36 283.40 283.22 24 283.11 283.01 283.34 283.39 283.44 283.41 283.22 283.17 283.31 283.35 283.39 283.20 25 283.11 283.11 283.35 283.45 283.43 283.41 283.22 283.18 283.34 283.35 283.38 283.19 26 283.13 283.11 283.33 283.46 283.37 283.41 283.22 283.16 283.36 283.35 283.38 283.18 27 283.12 283.12 283.27 283.47 283.35 283.42 283.23 283.14 283.37 283.35 283.37 283.18 28 283.12 283.16 283.22 283.47 283.35 283.42 283.27 283.14 283.37 283.35 283.35 283.18 29 283.11 283.16 283.17 283.47 --- 283.46 283.30 283.15 283.36 283.36 283.33 283.18 30 283.08 283.21 283.13 283.46 283.46 283.38 283.16 283.36 283.36 283.28 283.20 31 283.09 --- 283.17 283.44 283.44 --- 283.17 --- 283.36 283.36 LOW 283.21 283.35 283.47 283.48 283.48 283.46 283.37 283.36 283.46 283.39 HIGH 283.00 246.99 283.23 283.35 283.31 283.22 283.17 283.21 283.28 283.18 243 GROUND-WATER LEVELS RIO GRANDE DE MANATI BASIN 182454066315300. Local number, 142. LOCATION.--Lat 18°24'54", long 66°31'53". Owner: P.R. Aqueduct and Sewer Authority. Name: Moran Sim6. AQUIFER.--Aymamon Limestone. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 20 in (0.51 m) 0-147 ft (0-44.8 m), cased 20 in (0.51 m) 0-100 ft (0-30.5 m), diameter 16 in (0.41 m) 147-211 ft (44.8-64.3 m), diameter 12 in (0.30 m) 211-320 ft (64.3-97.6 m), cased 12 in (0.30 m) 0-320 ft (0-97.6 m), perforated 248-320 ft (75.6-97.6 m), diameter 10 in (0.25 m) 320-517 ft (97.6-158 m), cased 8 in (0.20 m) 300-517 ft (91.5-158 m), perforated 480-517 ft (146-158 m). Depth 517 ft (158 m). DATUM.--Altitude of land-surface datum is 492 ft (150 m) above mean sea level. Measuring point: top of 1.75 in (0.04 m) hole on top of 3 in (0.08 m) casing, 1.0 ft (0.30 m) above land surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--August 1981 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 226.5 ft (69.0 m) below land-surface datum, May 21, 1982; lowest water level measured, 228.8 ft (69.8 m) below land-surface datum, Dec. 16, 1981. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1980 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Aug. 25, 1981 228.0 June 17, 1982 227.8 Dec. 15, 1982 228.1 May 15, 1983 228.6 Dec. 16 228.8 July 26 228.0 Jan. 13, 1983 288.1 June 27 227.8 Feb. 17, 1982 227.4 Aug. 19 228.6 Feb. 3 228.2 July 18 228.3 Mar. 18 228.0 Sept 10 228.2 Mar. 7 227.2 Aug. 19 228.5 Apr. 15 227.8 Oct. 8 228.0 Apr. 5 228.4 Sept. 12 228.6 May 21 226.5 Nov. 5 228.1 182542066305100. Local numbel, 166. LOCATION.--Lat 18°25'42", long 66°30'51". Owner: P.R. Aqueduct and Sewer Authority. Name: Manati (New well). AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 20 in (0.51 m), cased 0-100 ft (0-39.49 m), diameter 14 in (0.36 m), cased 0-140 ft (0-42.68 m), slotted 80-90 ft (24.39-27.44 m) and 130-140 ft (39.63-42.68 m). Depth 140 ft (42.68 m). DATUM.--Altitude of land-surface datum is 29.52 ft (9.0 m) above mean-sea level. Measuring point: Top of 14 in (0.36 m) casing, 0.80 ft (0.24 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--January 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 22.90 ft (6.98 m) below land-surface datum, Mar. 3, 1983; lowest water level measured, 26.36 ft (8.04 m) below land-surface datum, Feb. 3, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Jan. 14, 1982 24.35 July 26, 1982 25.20 Dec. 15, 1982 25.05 May 12, 1983 24.85 Feb. 16 23.57 Aug. 19 25.37 Jan. 13, 1983 24.88 June 28 25.16 Mar. 17 24.96 Sept. 10 25.27 Feb. 3 26.36 July 15 25.20 Apr. 15 25.16 Oct. 8 24.99 Mar. 3 22.90 Aug. 19 25.55 May 21 24.53 Nov. 5 25.10 Apr. 6 25.45 Sept. 12 25.47 June 17 25.04 244 GROUND-WATER LEVELS RIO CIBUCO BASIN 182446066194801. Local number, 62. LOCATION.--Lat 18°24'46", long 66°19'48". Owner: P.R. Aqueduct and Sewer Authority. Name: Vega Alta 1. AQUIFER.--Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled public supply artesian well, diameter 16 to 12 in (41 to 30 cm), cased 16 in (41 cm) 0-50 ft (0-15.2 m), 12 in (30 cm) 0-110 ft (0-33.5 m). Depth 210 ft (64.0 m). DATUM.--Altitude of land-surface datum is about 102 ft (31.1 m) above mean sea level. Measuring point: Lower edge of 0.75 in (1.90 cm) pipe in pump base, 1.0 ft (0.30 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--January 1961 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, a80.8 ft (a24.6 m) below land-surface datum, Jan. 28, 1980; lowest measured, 137.9 ft (42.0 m) below land-surface datum, Mar. 3, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Date Water level Date Water level Date Water level Date Water level Oct. Nov. Dec. 8 5 15 a108.1 a116.3 a100.7 Jan. Feb. Mar. 13 3 3 a98.90 a113.0 a137.9 Apr. 5 May 13 June 28 al14.0 a114.5 a 99.90 July Aug. Sept. 15 19 20 al00.3 a121.5 a97.84 182647066201701. Local number, 70. LOCATION.--Lat 18°26'47", long 66°20'17". Owner: P.R. Aqueduct and Sewer Authority. Name: Sabana Hoyos. AQUIFER.--Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled unused artesian well, diameter 8 in (20 cm), cased 0-90 ft (0-27.4 m), perforated. Depth 90 ft (27.4 m) DATUM.--Altitude of land-surface datum is about 49 ft (14.9 m) above mean sea level. 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, 21.33 ft (6.50 m) below land-surface datum, Oct. 26, 1976; lowest, 31.10 ft (9.48 m) below land-surface datum, July 31, 1975. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM• WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 28.35 28.71 28.74 28.32 28.88 29.28 29.54 28.83 28.64 29.17 29.37 29.26 2 28.37 28.71 28.74 28.32 28.90 29.29 29.54 28.83 23.65 29.20 29.37 29.25 3 28.37 28.72 28.74 28.31 28.91 29.31 29.54 28.86 28.67 29.21 29.38 29.26 4 28.38 28.74 28.75 28.31 28.92 29.34 29.55 28.90 28.70 29.20 29.39 29.27 5 28.39 28.75 28.78 28.31 28.93 29.35 29.59 28.90 28.73 29.19 29.39 29.27 6 28.40 28.77 28.80 28.31 28.94 29.37 29.60 28.93 28.75 29.17 29.38 29.26 7 28.41 28.78 28.81 28.32 28.95 29.37 29.62 28.94 28.77 29.14 29.40 29.26 8 28.42 28.79 28.82 28.34 28.97 29.40 29.63 28.94 28.80 29.12 29.42 29.22 9 28.43 28.81 28.84 28.35 28.97 29.41 29.64 28.94 28.83 29.11 29.43 29.20 10 28.47 28.81 28.86 28.37 29.01 29.43 29.65 28.96 28.85 29.10 29.45 29.19 11 28.48 28.81 28.87 28.39 29.07 29.45 29.65 28.98 28.88 29.11 29.45 29.18 12 28.50 28.81 28.88 28.41 29.06 29.46 29.66 29.04 28.90 29.13 29.46 29.17 13 28.52 28,79 28.89 28.44 29.09 29.47 29.66 29.05 28.91 29.15 29.46 29.16 14 28.54 28.78 28.91 28.47 29.11 29.47 29.66 29.03 28.93 29.18 29.45 29.16 15 28.54 28.77 28.93 28.52 29.12 29.47 29.67 28.97 28.95 29.20 29.45 29.15 16 28.54 28.74 28.93 28.54 29.13 29.45 29.67 28.93 28.97 29.22 29.45 29.14 17 28.54 28.72 28.93 28.57 29.15 29.44 29.67 28.91 28.99 29.22 29.44 29.13 18 28.54 28.71 28.95 28.59 29.17 29.42 29.67 28.89 28.99 29.21 29.43 29.13 19 28.57 28.71 28.97 28.60 29.18 29.42 29.67 28.88 28.99 29.21 29.42 29.13 20 28.57 28.72 28.99 28.62 29.18 29.42 29.67 28.85 28.99 29.21 29.42 29.12 21 28.57 28.72 28.92 28.64 29.20 29.42 29.58 28.79 29.00 29.22 29.42 29.13 22 28.56 28.73 28.84 28.67 29.21 29.45 29.45 28.74 29.02 29.25 29.37 29.11 23 28.56 28.73 28.79 28.69 29.22 29.47 29.22 28.69 29.04 29.27 29.34 29.08 24 28.57 28.73 28.73 28.70 29.23 29.49 29.05 28.67 29.05 29.28 29.32 29.06 25 28.59 28.74 28.71 28.73 29.24 29.51 28.93 28.64 29.07 29.29 29.31 29.03 26 28.60 28.76 28.67 28.75 29.26 29.53 28.87 28.62 29.08 29.30 29.30 29.03 27 28.61 28.77 28.61 28.77 29.26 29.54 28.83 28.61 29.09 29.31 29.29 29.00 28 28.64 28.76 28.53 28.80 29.27 29.55 28.82 28.60 29.11 29.31 29.28 28.99 29 28.66 28.72 28.44 28.83 --- 29.56 28.82 28.60 29.12 29.31 29.27 28.99 30 28.68 28.73 28.37 28.84 29.55 28.82 28.60 29.14 29.33 29.26 28.99 31 28.70 --- 28.34 28.85 29.54 --- 28.61 --- 29.35 29.26 --- LOW 28.70 28.81 28.99 28.85 29.27 29.56 29.67 29.05 29.14 29.35 29.46 29.27 HIGH 28.35 28.71 28.34 28.31 28.88 29.28 28.82 28.60 28.64 29.10 29.26 28.99 CAL YR 1982 MEAN 27.69 LOW 28.99 HIGH 24.73 WTR YR 1983 MEAN 29.00 LOW 29.67 HIGH 28.31 a Pumping. 245 GROUND-WATER LEVELS RIO CIBUCO BASIN 182705066213500. Local number, 151. LOCATION.--Lat 18°27'05", long 66°21'35". Owner: AFDA - P.R. Department of Agriculture. Name: Rice Program #3. AQUIFER.--AymamOn Limestone. WELL CHARACTERISTICS.--Drilled agricultural water-table well, diameter 18 in (0.46 m), cased 0-80 ft (0-24.39 m), diameter 16 in (0.41 m), open hole 80-160 ft (24.39-48.78 m). Depth 160 ft (48.78). DATUM.--Altitude of land-surface datum is about 19.7 ft (6 m) above mean sea level. Measuring point: Hole on side of 18 in (0.46 m) casing, 2.4 ft (0.73 m) above land-surface datum. REMARKS.--Observation well. Irrigation water supply. PERIOD OF RECORD.--January 13, 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 3.72 ft (1.13 m) below land-surface datum, Jan. 13, 1982; lowest water level measured, 35.80 ft (10.91 m) below land-surface datum, Aug. 4, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Jan. 13, 1982 3.72 Feb. 16 4.42 May June 21, 1982 4.74 16 5.25 Nov. 5, 1982 Dec. 15 6.40 a28.05 May 12, 1983 6.60 June 27 6.85 24 a16.80 July 26 5.80 Jan. 13, 1983 6.25 July 15 a34.50 25 Mar. 17 4.70 4.76 Aug. Sept. 10 17 a41.78 5.86 Feb. Mar. 3 3 6.70 6.91 Aug. 4 19 a35.80 7.00 Apr. 15 a25.70 Oct. 8 6.00 Apr. 5 a33.10 Sept. 29 6.25 182612066225400. Local number, 155. LOCATION.--Lat 18°26'54", long 66°22'54". Owner: P.R. Aqueduct and Sewer Authority. Name: La Trocha. AQUIFER.--Aymam6n Limestone. WELL CHARACTERISTICS:--Drilled unused table well, diameter 20 in (0.51 m), cased 0-70 ft (0-21.34 m), diameter 16 in (0.41 m), cased 0-100 ft (0-30.49), perforated 100-200 ft (30.49-61.0 m). Depth 200 ft (61.0 m). DATUM.--Altitude of land-surface datum is about 49.20 ft (15.0 m) above mean sea level. Measuring point: Top of 20 in (0.51 m) casing, 2.1 ft (0.64 m) above land-surface datum. REMARKS.--Observation well. Never used as water supply well due to high concentrations of chlorides. PERIOD OF RECORD.--January 14, 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 32.23 ft (9.83 m) below land-surface datum, Jan. 14, 1982; lowest water level measured, 34.60 ft (10.55 m) below land-surface datum, Sept. 6, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Jan. 14, 1982 32.23 Apr. 15, 1982 33.56 Apr. 6, 1983 34.27 July 15, 1983 34.00 Feb. 16 34.02 May 21 33.26 May 12 33.95 Aug. 15 34.32 Mar. 17 34.38 June 16 33.48 June 27 34.08 Sept. 6 34.60 182652066241400. Local number, 156. LOCATION.--Lat 18°26'52", long 66°24'14". Owner: P.R. Aqueduct and Sewer Authority. Name: El Criollo #1. AQUIFER.--AymamOn Limestone. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 20 in (0.51 m), cased 0-98 ft (0-29.88 m), diameter 16 in (0.41 m), perforated 88-120 ft (26.83-36.58 m). Depth 120 ft (36.58 m). DATUM.--Altitude of land-surface datum is about 49.20 ft (15 m) above mean sea level. Measuring point: Upper edge of 2 in (0.05 m) pipe on pump base, 1.8 ft (0.55 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--January 14, 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, a40.52 ft (12.35 m) below land-surface datum, Feb. 16, 1982; lowest water level measured, a47.30 ft (14.42 m) below land-surface datum, Apr. 5, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Jan. 14, 1982 a45.60 July 26, 1982 a42.34 Dec. 15, 1982 42.28 May 12, 1983 a43.10 Feb. 16 a40.52 Aug. 17 a43.00 Jan. 13, 1983 a42.90 June 28 a43.29 Mar. 17 a40.88 Sept. 10 a43.16 Feb. 3 a43.10 July 15 a42.50 Apr. 15 a46.87 Oct. 8 a42.98 Mar. 7 a43.40 Aug. 18 a43.23 May 21 a40.60 Nov. 5 a42.61 Apr. 5 a47.30 Sept. 20 a43.06 June 16 a45.52 a Pumping. 246 GROUND-WATER LEVELS RIO CIBUCO BASIN 182654066211600. Local number, 167. LOCATION.--Lat 18°26'54", long 66°21'16". Owner: P. R. Land Authority, AFDA. Name: U.S.G.S. Observation Well #3. AQUIFER.--AymamOn Limestone. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m) 0-228 ft (0-69.5 m), open hole 228-238 ft (69.5-72.6 m). Depth 238 ft (72.6 m). DATUM.--Altitude of land-surface datum is 65.6 ft (20.0 m) above mean sea level. Measuring point: Top of 6 in (0.15 m) casing, 3.10 ft (0.94 m) above land-surface datum. REMARKS.--Observation well. Water levels affected by nearby pumpage. PERIOD OF RECORD.--January 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 13.07 ft (3.98 m) below land-surface datum, Jan. 13, 1982; lowest water level measured, c16.90 ft (5.15 m) below land-surface datum, Aug. 18, 1983. WATER LEVELS IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Date Jan. 13, 1982 Feb. 16 Mar. 17 Apr. 15 May 21 June 16 Water level 13.07 13.22 14.40 14.38 14.05 13.90 Date July 26, 1982 Aug. 17 Sept. 10 Oct. 8 Nov. 5 Water level 14.80 14.50 14.66 c14.95 c15.24 Date Dec. 15, 1982 Jan. 13, 1983 Feb. 3 Mar. 3 Apr. 5 Water level c15.47 c15.12 c15.30 c15.90 c16.00 Date May 12, 1983 June 27 July 15 Aug. 18 Sept. 29 Water level c15.55 c15.70 c15.50 c16.90 c14.93 182751066221600. Local number, 168. LOCATION.--Lat 18°27'51", long 66°22'16". Owner: AFDA. P.R. Department of Agriculture. Name: Rice Program #4. AQUIFER.--Aymamiin Limestone. WELL CHARACTERISTICS.--Drilled agricultural water-table well, diameter 16 in (0.41 m), cased 16 in (0.41 m) 0-156 ft (0-32.3 m), slotted 56-106 ft (17.07-32.3 m), open hole 106-150 ft (32.3-45.7 m). Depth 150 ft (45.73 m). DATUM.--Altitude of land-surface datum is about 9.84 ft (3 m) above mean sea level. Measuring point: Top of 16 in (0.41 m) casing, 0.8 ft (0.24 m) above land-surface datum. REMARKS.--Observation well. Irrigation water supply well. PERIOD OF RECORD.--March 17, 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 4.88 ft (1.49 m) below land-surface datum, Mar. 17, 1982; lowest water level measured, a53.85 ft (16.42 m) below land-surface datum, July 26, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 17, 1982 4.88 Aug. 17, 1982 a43.40 Feb. 3, 1983 a46.75 July 15, 1983 a44.60 Apr. 15 5.04 Oct. 8 a42.30 Mar. 3 a44.45 Aug. 4 a44.90 May 21 a26.25 Nov. 5 a44.50 May 12 5.40 18 a41.26 June 16 a34.40 Dec. 15 a40.24 June 27 a38.30 Sept. 29 a43.20 July 26 a53.85 Jan. 13, 1983 a44.02 182740066223100. Local number, 169. LOCATION.--Lat 18°27'40", long 66°22'31". Owner: AFDA. P.R. Department of Agriculture. Name: Rice Program #5. AQUIFER.--AymamOn Limestone. WELL CHARACTERISTICS.--Drilled agricultural water-table well, diameter 16 in (0.41 m), cased 16 in (0.41 m) 0-80 ft (0-24.39 m), open hole 80-140 ft (24.39-42.68 m). Depth 140 ft (42.68 m). Datum.--Altitude of land-surface datum is about 13.10 ft (4.0 m) above mean sea level. Measuring point: Top of 16 in (0.41 m) casing, 0.10 ft (0.03 m) above land-surface datum. REMARKS.--Observation well. Irrigation water supply well. PERIOD OF RECORD.--March 17, 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 6.15 ft (1.88 m) below land-surface datum, Mar. 17, 1982; lowest water level measured, a15.60 ft (4.76 m) below land-surface datum, July 26, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 17, 1982 6.15 Apr. 15 6.30 May 21 6.60 June 16 6.80 July 26 a15.60 Aug. 17, 1982 Sept. 10 Oct. 8 Nov. 5 Dec. 14 6.67 6.55 6.50 a13.68 a13.45 Jan. 13, 1983 Mar. 3 Apr. 5 May 12 a12.29 al3.60 a12.67 al2.10 June 27, 1983 July 15 Aug. 18 Sept. 29 a13.00 al2.90 6.50 6.19 a Pumping. c Pumping nearby well. 247 GROUND-WATER LEVELS RIO DE LA PLATA BASIN 180707066084201. Local number, 33. LOCATION.--Lat 18°07'07", long 66°08'42". Owner: P.R. Aqueduct and Sewer Authority. Name. Cayey 10. AQUIFER.--Volcanic rocks of Cretaceous Age. WELL CHARACTERISTICS.--Drilled public supply artesian well, diameter 16 to 12 in (41 to 30 cm), cased 16 in (41 cm) 0-30 ft (0-9.1 m), 12 in (30 cm) 0-200 ft (0-61.0 m), perforated 30-200 ft (9.1-61.0 m), gravel packed 0-190 ft (0-57.9 m). Depth 220 ft (67.1 m). DATUM.--Altitude of land-surface datum is about 1,280 ft (390.1 m) above mean sea level. Measuring point: Lower edge of 0.75 in (1.90 cm) pipe in pump base, 1.2 ft (0.37 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--September 1959 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 1.49 ft (0.45 m) below land-surface datum, Jan. 18, 1961; lowest measured, a169.2 ft (a51.6 m) below land-surface datum, Dec. 10, 1976. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water WATER Water Date level Date level Date level Date level Oct. 4 a98.70 Jan. 18 a35.87 Apr. 4 al04.3 July 11 a39.40 Nov. 10 a98.30 Feb. 7 a95.50 May 5 a 93.25 Aug. 18 a45.10 Dec. 14 al00.3 Mar. 17 a35.20 June 13 a 90.60 Sept. 14 a81.36 180853066095401. Local number, 37. LOCATION.--Lat 18°08'53", long 66°09'54". Owner: P.R. Aqueduct and Sewer Authority. Name: Barrio Rincon de Cidra. AQUIFER.--Volcanic rocks of Cretaceous Age. WELL CHARACTERISTICS.--Drilled water supply water-table well, diameter 16 to 8 in (41 to 20 cm), cased 16 in (41 cm) 0-30 ft (0-9.1 m), 12 in (30 cm) 0-43 ft (0-13.1 m), perforated 0-43 ft (0-13.1 m). Depth 200 ft (61.0 m). DATUM.--Altitude of land-surface datum is about 1,180 ft (359.7 m) above mean sea level. Measuring point: Lower edge at 0.75 in (1.90 cm) pipe, 1.9 ft (0.58 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--June 1960 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 14.38 ft (4.38 m) below land-surface datum, July 20, 1979; lowest measured, 62.87 ft (19.16 m) below land-surface datum, Jul. 5, 1961. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 4 22.80 Feb. 7 21.36 May 5 22.40 Aug. 18 20.67 Dec. 14 22.52 Mar. 17 22.54 June 13 21.12 Sept. 14 21.63 Jan. 18 20.29 Apr. 4 23.20 July 11 18.86 180823066154601. Local number, 38. LOCATION.--Lat 18°08'23", long 66°15'46". Owner: P.R. Aqueduct and Sewer Authority. Name: Barrio Robles. AQUIFER.--Volcanic rocks of Cretaceous Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 10 in (25 cm). Depth 82 ft (25.0 m). DATUM.--Altitude of land-surface datum is about 1,980 ft (603.7 m) above mean sea level. Measuring point: Top of clean-out door sill, 1.80 ft (0.55 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--September 1959 to current year; changed to a partial site on Sept. 2, 1981. EXTREMES FOR PERIOD OF RECORD.--Highest water level, 3.60 ft (1.10 m) above land-surface datum, Sept. 6, 1960; lowest, 51.47 ft (15.69 m) below land-surface datum, Sept. 30, 1977. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 4 18.29 Jan. 18 9.97 Apr. 4 12.33 July 11 8.25 Nov. 10 14.76 Feb. 7 10.98 May 5 9.02 Aug. 18 9.47 Dec. 14 11.96 Mar. 17 10.35 June 13 11.62 Sept. 14 9.47 a Pumping. 248 GROUND-WATER LEVELS RIO DE LA PLATA BASIN 182518066144201. Local number, 67. LOCATION.--Lat 18°25'18", long 66°14'42". Owner: P.R. Aqueduct and Sewer Authority. Name: Campanilla. AQUIFER.--Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 12 in (30 cm). Depth 300 ft (91.4 m). DATUM.--Altitude of land-surface datum is about 390 ft (118.9 m) above mean sea level. Measuring point: Lower edge of 0.75 in (1.90 cm) pipe, 1.0 ft (0.30 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--March 1959 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 27.91 ft (8.51 m) below land-surface datum, Dec. 16, 1981; lowest measured, 49.90 ft (15.21 m) below land-surface datum, June 6, 1967. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 21 Dec. 9 34.93 33.38 Feb. 3 34.10 July 12 33.22 Sept. 20 34.25 182636066164201. Local number, 69. LOCATION.--Lat 18°26'36", long 66°16'42". Owner: P.R. Aqueduct and Sewer Authority. Name: Higuillar. AQUIFER.--Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 10 in (25 cm). Depth 200 ft (61.0 m). DATUM.--Altitude of land-surface datum is about 60 ft (18.3 m) above mean sea level. Measuring point: Airline hole in pump base, 1.1 ft (0.34 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--July 1958 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 41.21 ft (12.56 m) below land-surface datum, July 3, 1958; lowest measured, 58.89 ft (17.95 m) below land-surface datum, Oct. 26, 1977. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 26 a53.20 Feb. 3 a53.63 May 31 a50.71 Aug. 25 a53.07 Nov. 17 a53.11 Mar. 8 a54.55 June 20 a52.08 Sept. 20 a53.17 Dec. 9 a53.55 Apr. 23 a54.42 July 13 a52.15 182623066181400. Local number, 150. LOCATION.--Lat 18°26'23", long 66°18°14". Owner: Department of Agriculture, Land Authority; loaned to Puerto Rico Aqueduct and Sewer Authority. Name: Monterey Forestal. AQUIFER.--Aymamtin Limestone. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 12 in (0.30 m), cased 12 in (0.30 m) 0-300 ft (0-91 5 m), open hole 300-400 ft (91.5-122 m). Depth 400 ft (122 m). DATUM.--Altitude of land-surface datum is 131.2 ft (40 m) above mean sea level. Measuring point: Bottom edge of 1 in (2.54 cm) pipe on top of pump concrete base, 1.0 ft (0.30 m) above land-surface datum. REMARKS.--Irrigation supply observation well. PERIOD OF RECORD.--January 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 184.3 ft (56.2 m) below land-surface datum, Sept. 20, 1983; lowest water level measured, a210.9 ft (64.3 m) below land-surface datum, Apr. 15, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Jan. 13, 1982 Feb. 16 190.3 191.3 July Aug. 26, 1982 17 195.2 203.0 Dec. 15, 1982 Jan. 13, 1983 199.9 208.1 May June 13, 1983 28 195.6 197.8 Mar. 17 Apr. 15 May 21 205.4 a210.9 197.0 Sept. 10 Oct. 8 Nov. 5 207.9 a197.6 a199.7 Feb. Mar. Apr. 3 3 5 204.1 207.7 207.6 July 15 Aug. 19 Sept. 20 199.8 a206.8 184.3 a Pumping. 249 GROUND-WATER LEVELS RIO DE BAYAMON AND RIO PIEDRAS BASINS 181047066091701. Local number, 42. LOCATION.--Lat 18°10'47", long 66°09'17". Owner: P.R. Aqueduct and Sewer Authority. Name: Cidra 2. AQUIFER.--Volcanic rocks of Cretaceous Age. WELL CHARACTERISTICS.--Drilled public supply artesian well, diameter 13 in (33 cm), cased 0-64 ft (0-19.5 m), perforated 16-64 ft (4.9-19.5 m). Depth 92 ft (28.0 m). DATUM.--Altitude of land-surface datum is about 1,340 ft (408.4 m) above mean sea level. Measuring point: Airline hole in pump base, 1.4 ft (0.43 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--September 1959 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 12.30 ft (3.75 m) below land-surface datum, Dec. 27, 1979; lowest measured, 56.32 ft (17.17 m) below land-surface datum, Apr. 1, 1968. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 4 Nov. 10 Dec. 14 15.25 16.37 17.29 Jan. 18 Feb. 7 Mar. 17 17.95 19.37 20.78 Apr. 4 May 5 June 13 22.54 22.62 19.20 July 11 Aug. 18 Sept. 14 18.89 19.50 16.79 182506066030801. Local number, 65. LOCATION.--Lat 18°25'06", long 66°03'08". Owner: P.R. Aqueduct and Sewer Authority. Name: Hato Rey Central, McCracken well. AQUIFER.--Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 15 in (38 cm), cased 0-205 ft (0-62.5 m), perforated 64-205 ft (19.5-62.5 m). Depth 205 ft (62.5 m). DATUM.--Altitude of land-surface datum is about 33 ft (10.1 m) above mean sea level. Measuring point: Top of casing, 3.4 ft (1.04 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--July 1958 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 22.40 ft (6.83 m) below land-surface datum, Aug. 12, 1976; lowest measured, 42.40 ft (12.92 m), below land-surface datum, May 13, 1974. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 6 31.41 Jan. 19 31.30 Apr. 20 31.35 July 11 31.29 Nov. 9 31.28 Feb. 3 31.35 May 9 31.27 Aug. 8 31.54 Dec. 28 30.81 Mar. 15 31.44 June 23 31.52 Sept. 15 31.35 182547066110801. Local number, 66. LOCATION.--18°25'47", long 66°11'08". Owner: P.R. Aqueduct and Sewer Authority. Name: Sabana Seca. AQUIFER.--Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well. Depth 130 ft (39.6 m). DATUM.--Altitude of land-surface datum is about 75 ft (22.9 m) above mean sea level. Measuring point: Lower edge of 0.75 in (1.90 cm) pipe in pump base, 1.2 ft (0.37 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--June 1958 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, a39.23 ft (a11.96 m) below land-surface datum, Dec. 17, 1981; lowest measured, 57.75 ft (17.60 m), below land-surface datum, Aug. 13, 1976. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Nov. 17 a43.35 Mar. 10 a44.47 June 20 a42.97 Aug. 25 a43.54 Dec. 8 a43.48 May 31 a42.74 July 12 a43.20 Sept. 20 a43.60 Feb. 3 a43.88 a Pumping. 250 GROUND-WATER LEVELS RIO GRANDE DE LOIZA BASIN 181550065593201. Local number, 50. LOCATION.--Lat 18°15'50", long 65°59'32". Owner: Gurabo Agricultural Experimental Station. Name: Gurabo. AQUIFER.--Unconsolidated deposits of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 13 in (33 cm). Depth 145 ft (44.2 m). DATUM.--Altitude of land-surface datum is about 148 ft (45.1 m) above mean sea level. Measuring point: Top of 12 in (30 cm) casing, 0.8 ft (0.24 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--December 1960 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 12.65 ft (3.86 m) below land-surface datum, Sept. 9, 1975; lowest measured, 44.38 ft (13.53 m) below land-surface datum, June 18, 1975. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Date Water level Date Water level Date Water level Date Water level Oct. 8 Nov. 4 Dec. 28 29.05 28.53 25.93 Jan. 18 Feb. 8 Mar. 17 28.19 28.14 28.19 Apr. 6 May 5 June 28 28.25 26.18 28.85 July 20 Aug. 18 Sept. 12 28.81 29.78 29.57 181538066021301. Local number, 52. LOCATION.--Lat 18°15'38", long 66°02'13". Owner: P.R. Aqueduct and Sewer Authority. Name: Bairoa. AQUIFER.--Unconsolidated deposits of Quaternary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 16 to 10 in (41 to 25 cm) 0-69 ft (0-21.0 m), 79-100 ft (24.1-30.5 m), 110-116 ft (33.5-35.4 m), perforated 79-100 ft (24.1-30.5 m), screened 69-79 ft (21.0-24.1 m) and 100-110 ft (30.5-33.5 m), gravel packed to 113 ft (34.4 m). Depth 116 ft (35.4 m). DATUM.--Altitude of land-surface datum is about 200 ft (61.0 m) above mean sea level. Measuring point: Airline hole in pump base, 1.4 ft (0.43 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--July 1959 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, +0.92 ft (+0.28 m) below land-surface datum, Nov. 15, 1979; lowest measured, a115.1 ft (a35.1 m) below land-surface datum, June 18, 1975. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 8 a80.28 Jan. 18 a74.78 Apr. 6 a75.96 July 20 a74.85 Nov. 8 a77.37 Feb. 8 a74.24 May 5 a75.05 Aug. 18 a74.78 Dec. 28 a72.89 Mar. 17 a74.64 June 28 a74.17 Sept. 20 a75.10 RIO HUMACAO TO RIO SECO BASINS 175735066095901. Local number, 2. LOCATION.--Lat 17°57'35", long 66°09'59". Owner: P.R. Aqueduct and Sewer Authority. Name: Puente Jobos. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 21 in (53 cm). Depth 148 ft (45.1 m). DATUM.--Altitude of land-surface datum is about 26 ft (7.9 m) above mean sea level. Measuring point: Bottom edge of 0.88 in (2.24 cm) pipe, 1.7 ft (0.52 m) above land-surface datum. REMARKS.--Observation well. Lowest water level is a pumping level. PERIOD OF RECORD.--February 1961 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 2.85 ft (0.87 m) below land-surface datum, July 24, 1979; lowest measured, 61.78 ft (18.83 m) below land-surface datum, Aug. 6, 1964. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 18 6.01 Jan. 14 5.96 Apr. 8 6.60 Aug. 4 7.04 Nov. 16 5.51 Feb. 10 6.42 May 6 6.12 Sept. 13 6.99 Dec. 10 5.51 Mar. 11 6.17 July 15 7.07 + Above land-surface datum. a Pumping. 251 GROUND-WATER LEVELS RIO HUMACAO TO RIO SECO BASINS 175734066100401. Local number, 3. LOCATION.--Lat 17°57'34", long 66°10'04". Owner: P.R. Aqueduct and Sewer Authority. Name: Jobos. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Bored unused artesian well, diameter 4 in (10 cm). Depth 16 ft (4.9 m). DATUM.--Altitude of land-surface datum is about 25 ft (7.6 m) above mean sea level. Measuring point: Top of 5 in (13 cm) fitting, 0.5 ft (0.15 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--November 1959 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 0.01 ft (0.003 m) below land-surface datum, Jan. 3, 1963; lowest measured, dry at 16 ft (4.9 m) below land-surface datum, many days during 1968 and 1969. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Date Water level Date Water level Date Water level Date Water level Oct. 18 Nov. 16 Dec. 10 1.46 1.84 1.90 Jan. Feb. Mar. 14 10 11 2.30 2.94 2.45 Apr. 8 May 6 June 28 3.10 2.42 2.35 July 15 Aug. 4 Sept. 13 2.50 2.40 1.60 175858066100201. Local number, 6. LOCATION.--Lat 17°58'58", long 66°10'02". Owner: Doctor Bruno. Name: Juana 5. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 16 in (41 cm). Depth 173 ft (52.7 m) reported, 110 ft (33.5 m) measured. DATUM.--Altitude of land-surface datum is about 127 ft (38.7 m) above mean sea level. Measuring point: Top of shelter floor, 3.0 ft (0.91 m) above land-surface datum. After Aug. 7, 1981, top of 16" casing, 1.55 ft (0.47 m) above land-surface datum. REMARKS.--Recorder installed Jan. 25, 1962. PERIOD OF RECORD.--November 1960 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 26.20 ft (7.99 m) below land-surface datum, Dec. 10, 1979; lowest measured, 65.95 ft (20.10 m) below land-surface datum, June 2, 1968. WATER LEVEL. IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 50.34 52.67 53.72 54.59 54.94 53.90 53.30 54.25 56.49 58.13 57.19 54.97 2 50.65 52.73 53.73 54.61 54.97 53.87 53.37 54.30 56.58 58.16 56.97 54.92 3 50.89 52.80 53.75 54.64 55.01 53.88 53.44 54.36 56.66 58.17 56.73 54.89 4 51.09 52.88 53.78 54.68 55.06 53.90 53.51 54.41 56.76 58.19 56.47 54.85 5 51.25 52.99 53.81 54.71 55.13 53.91 53.60 54.47 56.84 58.20 56.24 54.83 6 51.41 53.10 53.84 54.76 55.19 53.93 53.69 54.53 56.94 58.21 56.02 54.82 7 51.55 53.17 53.87 54.80 55.25 53.96 53.72 54.57 57.02 58.22 55.84 54.83 8 51.64 53.26 53.90 54.83 55.32 54.00 53.71 54.61 57.12 58.24 55.68 54.85 9 51.64 53.30 53.92 54.86 55.38 54.04 53.65 54.66 57.21 58.25 55.56 54.87 10 51.49 53.31 53.95 54.89 55.42 54.05 53.62 54.71 57.30 58.26 55.46 54.90 11 51.36 53.34 53.98 54.92 55.44 54.05 53.69 54.77 57.39 58.27 55.38 54.93 12 51.29 53.38 54.01 54.96 55.45 54.06 53.75 54.83 57.48 58.28 55.32 54.97 13 51.44 53.44 54.05 54.90 55.43 54.09 53.71 54.91 57.57 58.29 55.30 55.02 14 51.61 53.50 54.08 54.85 55.41 54.13 53.59 54.98 57.64 58.30 55.28 55.07 15 51.68 53.57 54.12 54.91 55.40 54.16 53.54 55.06 57.70 58.32 55.26 55.12 16 51.75 53.67 54.16 54.83 55.35 54.21 53.51 55.13 57.76 58.33 55.25 55.17 17 51.82 53.72 54.21 54.82 55.21 54.28 53.56 55.21 57.79 58.35 55.25 55.22 18 51.89 53.76 54.25 54.92 55.02 54.36 53.62 55.30 57.83 58.36 55.24 55.27 19 51.95 53.79 54.30 54.99 54.86 54.44 53.66 55.39 57.86 58.34 55.23 55.32 20 52.02 53.82 54.34 55.05 54.70 54.51 53.73 55.48 57.88 58.29 55.22 55.36 21 52.08 53.84 54.38 55.12 54.57 54.56 53.73 55.57 57.90 58.23 55.22 55.39 22 52.15 53.86 54.41 55.18 54.44 54.56 53.77 55.65 57.92 58.19 55.24 55.43 23 52.18 53.88 54.45 55.18 54.34 54.55 53.82 55.74 57.94 58.16 55.25 55.46 24 52.22 53.91 54.47 55.14 54.26 54.49 53.86 55.82 57.96 58.11 55.22 55.50 25 52.28 53.90 54.49 55.04 54.19 54.41 53.90 55.90 57.99 58.08 55.18 55.53 26 52.34 53.86 54.49 54.93 54.13 54.34 53.95 55.99 58.01 58.02 55.14 55.51 27 52.39 53.82 54.49 54.83 54.04 54.23 54.01 56.07 58.04 57.94 55.12 55.46 28 52.44 53.78 54.50 54.77 53.95 53.98 54.07 56.16 58.06 57.83 55.10 55.41 29 52.50 53.75 54.52 54.82 --- 53.70 54.14 56.24 58.09 57.70 55.10 55.37 30 52.56 53.73 54.54 54.88 53.43 54.20 56.33 58.11 57.56 55.07 55.32 31 52.62 --- 54.57 54.91 53.28 --- 56.41 --- 57.39 55.03 LOW 52.62 53.91 54.57 55.18 55.45 54.56 54.20 56.41 58.11 58.36 57.19 55.53 HIGH 50.34 52.67 53.72 54.59 53.95 53.28 53.30 54.25 56.49 57.39 55.03 54.82 CAL YR 1982 MEAN 50.08 LOW 54.57 HIGH 43.09 WTR YR 1983 MEAN 54.88 LOW 58.36 HIGH 50.34 252 GROUND-WATER LEVELS RIO HUMACAO TO RIO SECO BASINS 175944066033601. Local number, 15. LOCATION.--Lat 17°59'44", long 66°03'36". Owner: P.R. Aqueduct and Sewer Authority. Name: Pitahaya 1. AQUIFER.--Volcanic rocks of Cretaceous Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 12 in (30 cm). Depth 181 ft (55.2 m). DATUM.--Altitude of land-surface datum is about 130 ft (39.6 m) above mean sea level. Measuring point: Bottom of inspection door, 1.10 ft (0.34 m) above land-surface datum. REMARKS.--Recording observation well. Water levels affected by pumping of nearby well. PERIOD OF RECORD.--September 1959 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level, 3.00 ft (0.91 m) below land-surface datum, Oct. 7, 1970; lowest, 43.90 ft (13.38 m) below land-surface datum, May 20, 1968. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 8.20 10.52 9.88 12.74 17.87 20.94 24.80 11.63 8.87 9.63 9.66 9.84 2 8.38 10.53 10.02 12.58 18.11 21.20 25.13 12.07 9.29 9.86 9.76 10.04 3 8.57 10.61 10.20 12.86 18.25 21.38 25.29 12.55 9.71 9.41 9.83 10.15 4 8.75 10.81 10.38 13.16 18.41 21.59 25.35 13.16 10.12 9.13 9.93 10.32 5 8.92 11.02 10.56 13.63 19.22 21.95 25.59 13.57 10.58 8.30 10.06 10.48 6 9.14 11.20 10.74 13.91 18.81 22.22 25.79 14.09 11.02 7.69 10.04 10.61 7 9.33 11.42 10.90 14.07 19.00 22.54 26.07 14.73 11.45 7.63 10.04 10.73 3 9.49 11.62 11.06 14.36 18.98 22.31 26.52 15.35 11.92 7.60 10.13 10.82 9 9.63 10.55 11.20 14.57 19.06 21.96 27.38 16.10 12.48 7.73 10.25 10.92 10 9.80 10.25 11.33 14.66 19.70 21.51 27.38 17.07 13.21 7.90 10.38 11.04 11 10.02 10.50 11.47 14.81 19.38 20.90 27.38 17.81 13.87 8.08 10.52 11.15 12 10.09 8.76 11.62 14.74 19.74 20.51 27.38 18.36 14.92 8.31 10.69 11.20 13 10.25 8.20 11.75 15.01 19.84 20.25 27.28 18.83 16.21 8.52 10.82 11.22 14 10.45 8.26 11.90 15.42 19.93 19.91 27.38 19.37 17.34 8.71 10.75 11.36 15 10.61 8.49 12.05 15.69 19.89 19.75 27.38 19.48 17.82 8.93 10.92 11.47 16 10.82 8.77 12.12 15.86 19.72 19.92 27.38 18.85 11.21 9.13 11.08 11.52 17 10.94 9.05 12.25 15.84 19.70 20.21 27.38 18.33 8.75 9.24 10.90 11.62 18 10.85 9.33 12.40 16.13 19.85 20.50 27.38 18.01 8.26 9.30 9.73 11.70 19 10.90 8.46 12.55 16.29 20.03 20.95 20.79 16.99 7.97 9.44 9.31 11.78 20 10.60 8.23 12.64 16.44 20.24 21.44 13.85 13.54 7.91 9.50 9.40 11.86 21 10.39 8.54 12.81 16.57 20.33 21.94 10.70 12.27 7.93 9.70 9.29 11.00 22 10.32 8.88 12.96 16.84 20.52 22.50 9.16 12.04 8.01 9.91 3.34 10.36 23 9.85 9.14 13.08 16.91 20.63 22.81 8.81 11.32 8.10 10.14 8.54 10.57 24 9.15 9.32 13.28 16.90 20.84 22.82 8.79 9.05 8.26 9.74 8.87 10.75 25 9.11 9.53 13.46 17.06 20.96 23.08 9.04 8.25 8.52 9.37 9.19 10.92 26 9.31 9.71 13.62 17.06 20.93 23.40 9.46 8.06 8.85 9.42 9.43 10.91 27 9.71 9.89 13.84 16.99 20.67 23.63 9.93 8.07 9.13 9.63' 9.69 10.89 28 9.99 10.03 14.10 17.14 20.74 23.83 10.35 8.12 8.76 9.82 9.54 11.03 29 10.08 10.13 14.42 17.40 --- 23.20 10.77 8.25 8.91 9.86 9.24 11.22 30 10.38 9.98 14.75 17.54 24.29 11.20 8.43 9.26 9.56 9.40 11.38 31 10.52 --- 14.39 17.67 24.60 --- 8.54 --- 9.55 9.62 --- LOW 10.94 11.62 14.75 17.67 20.96 24.60 27.38 19.48 17.82 10.14 11.08 11.86 HIGH 8.20 8.20 9.88 12.58 17.87 19.75 8.79 8.06 7.91 7.60 8.34 9.84 CAL YR 1982 MEAN 12.00 LOW 23.49 HIGH 7.41 WTR YR 1983 MEAN 13.56 LOW 27.38 HIGH 7.60 180338065523301. Local number, 31. LOCATION.--Lat 18°03'38", long 65°52'33". Owner: P.R. Aqueduct and Sewer Authority. Name: Central Roig. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 20 in (51 cm), 0-120 ft (0-36.6 cm), 12 in (30 cm) 120-125 ft (36.6-38.1 m), cased 0-125 ft (0-38.1 m), perforated 40-125 ft (12.2-38.1 m). Depth 125 ft (38.1 m). DATUM.--Altitude of land-surface datum is about 41 ft (12.5 m) above mean sea level. Measuring point: Airline hole in pump base, 4.0 ft (1.22 m) above land-surface datum. REMARKS.--Observation well. Drilled 5 ft (1.5 m) into rock. Affected by nearby pumping. PERIOD OF RECORD.--July 1959 to August 1973; April 1975 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 5.86 ft (1.79 m) below land-surface datum, Sept. 20, 1960; lowest measured, a50.57 ft (a15.41 m) below land-surface datum, July 7, 1977. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Nov. 8 a35.44 Feb. 11 a38.75 May 12 a44.25 Aug. 9 a38.46 Dec. 16 a33.25 Mar. 15 a43.20 June 27 a40.10 Sept. 13 a34.48 Jan. 19 a45.88 Apr. 15 a44.17 July 12 a38.70 a Pumping. 253 GROUND-WATER LEVELS RIO HUMACAO TO RIO SECO BASINS 175641066085101. Local number, 89. LOCATION.--Lat 17°56'41", long 66°08'51". Owner: Phillips Puerto Rico Core, Inc. Name: Phillips observation well 3. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled test well, diameter 4 in (10 cm). Depth 114 ft (34.7 m). DATUM.--Altitude of land-surface datum is about 6 ft (1.8 m) above mean sea level. Measuring point: Top of casing, 2.25 ft (0.69 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--October 1968 to current year; changed to a partial site on Oct. 1, 1981. EXTREMES FOR PERIOD OF RECORD.--Highest water level, +2.70 ft (+0.82 m) above land-surface datum, Jan. 9, 1973; lowest, 4.32 ft (1.32 m) below land-surface datum, June 5, 1981. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Date level Date level Date level Date level Water Water Water Oct. 18 1.13 Jan. 14 1.59 Apr. 8 2.13 July 15 1.16 Nov. 16 1.40 Feb. 10 1.70 May 6 1.92 Aug. 4 1.32 Dec. 10 1.28 Mar. 11 1.92 June 28 1.42 Sept. 13 1.00 180327065515301. Local number, 95. LOCATION.--Lat 18°03'27", long 65°51'53". Owner: P.R. Aqueduct and Sewer Authority. Name: USGS TW-5 or Yabucoa 10. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled observation water-table well, diameter 6 in (15 cm), cased 0-108 ft (0-32.9 m), slotted 50-108 ft (15.2-32.9 m). Depth 120 ft (36.6 m). DATUM.--Altitude of land-surface datum is about 26 ft (7.9 m) above mean sea level. Measuring point: Top of shelter floor, 3.0 ft (0.91 m) above land-surface datum. REMARKS.--Recording observation well. PERIOD OF RECORD.--April 25, 1978 to May 15, 1983 (discontinued). EXTREMES FOR PERIOD OF RECORD.--Highest water level, 4.68 ft (1.43 m) below land-surface datum, Aug. 31, 1979; lowest, 19.36 ft (5.90 m) below land-surface datum, Sept. 28, 1980. LOWEST WATER LEVEL IN FEET BELOW LAND-SURFACE DATUM ON 5TH, 10TH, 15TH, 20TH, 25TH AND LAST DAY OF MONTH. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 5 10.79 b11.80 b10.15 10.51 b11.10 b12.15 b12.65 10 b11.00 11.97 b10.20 9.88 11.33 b12.35 b12.50 15 b11.20 12.17 b10.30 10.09 b11.45 12.58 b12.35 11.48 20 b11.30 11.27 10.68 10.67 b11.65 b12.65 25 b11.50 b 9.75 10.04 10.73 b11.85 b12.70 EOM b11.70 b10.00 10.36 11.05 b11.95 b12.75 + Above land-surface datum. b Estimated. 254 GROUND-WATER LEVELS RIO HUMACAO TO RIO SECO BASINS 180416065514101. Local number, 96. LOCATION.--Lat 18°04'16", long 65°51'41". 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 (41 cm) cased 0-10 ft (0-3.0 m), diameter 6 in (15 cm), cased about 0-183 ft (0-55.8 m), perforated 56-81 ft (17.1-24.7 m), 102-123 ft (31.1-37.5 m), 144-181 ft (43.9-55.2 m). Depth 181 ft (55 2 m) DATUM.--Altitude of land-surface datum is about 25 ft (7.6 m) above mean sea level. Measuring point: Top of shelter floor, 4.0 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, 15.52 ft (4.73 m) below land-surface datum, Jan. 15, 1982; lowest, 28.29 ft (8.62 m) below land-surface datum, Sept. 20, 1980. WATER LEVEL. IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 17.73 19.56 19.39 18.29 19.80 19.47 22.99 21.95 20.68 22.17 19.51 18.77 2 17.77 19.69 19.28 18.36 19.80 19.66 23.04 21.59 20.75 22.19 19.51 18.88 3 17.79 19.87 19.16 18.40 19.84 19.92 23.00 21.38 20.85 22.20 19.82 19.24 4 17.88 20.07 19.05 18.46 19.92 20.19 22.94 21.72 21.00 21.81 19.90 19.22 5 17.99 20.29 18.94 18.58 20.02 20.40 22.89 22.07 21.06 21.45 19.90 19.22 6 18.12 20.50 18.83 18.61 20.13 20.53 22.85 22.37 21.11 21.20 20.16 18.71 7 18.20 20.69 18.76 18.55 20.23 20.62 22.91 22.19 21.19 20.58 20.10 18.63 8 18.29 20.83 18.73 18.42 20.31 20.66 22.99 22.29 21.34 20.36 20.28 18.66 9 18.48 20.92 13.72 18.28 20.28 20.70 23.03 22.46 21.44 20.23 20.46 18.76 10 18.70 21.00 18.71 18.12 20.19 20.74 23.07 22.77 21.52 20.48 20.23 19.32 11 18.92 21.05 18.70 17.99 20.08 20.84 23.01 23.02 21.51 20.36 20.24 18.80 12 19.14 21.06 18.70 17.87 20.01 21.01 22.95 23.21 21.46 20.40 20.35 13.60 13 19.33 21.08 18.71 17.77 19.96 21.19 22.90 23.35 21.40 19.97 20.29 19.28 14 19.53 21.08 18.72 17.84 19.87 21.34 22.81 23.44 21.39 19.83 20.03 19.61 15 19.73 21.09 13.67 18.05 19.76 22.64 22.62 23.41 21.40 19.81 19.52 19.86 16 19.92 21.04 18.57 18.24 19.70 21.53 21.86 23.17 21.50 19.80 20.39 20.07 17 20.06 20.99 18.45 18.44 19.73 21.63 20.99 22.59 21.69 19.75 20.37 19.41 18 20.05 20.95 18.36 18.65 19.84 21.72 21.07 22.48 21.37 20.02 20.74 19.05 19 19.92 20.88 18.28 18.87 19.90 21.79 21.12 22.76 21.40 19.98 20.90 18.85 20 19.88 20.81 18.18 19.10 19.86 21.86 21.00 22.71 20.60 20.21 20.85 18.78 21 19.82 20.70 18.08 19.31 19.74 21.96 19.52 22.58 20.30 20.35 20.66 18.93 22 19.74 20.56 18.00 19.47 19.62 22.08 19.76 22.34 20.53 20.59 20.53 19.50 23 19.69 20.41 17.93 19.60 19.59 22.20 20.24 22.05 20.75 20.85 19.77 19.74 24 19.64 20.29 17.88 19.69 19.52 22.32 20.43 21.62 21.02 20.69 19.45 19.90 25 19.57 20.17 17.84 19.75 19.45 22.43 20.45 21.57 21.21 20.23 19.18 19.32 26 19.51 20.06 17.83 19.77 19.42 22.52 20.61 21.56 21.40 20.13 18.86 19.11 27 19.50 19.94 17.86 19.79 19.40 22.60 20.85 21.66 21.48 20.18 18.89 19.04 28 19.55 19.83 17.91 19.81 19.37 22.66 21.40 21.58 21.72 19.83 18.57 19.00 29 19.63 19.68 17.99 19.86 --- 22.75 21.88 21.16 21.75 19.79 18.42 18.99 30 19.61 19.53 18.08 19.83 22.84 22.20 20.94 21.96 19.77 18.45 18.99 31 19.58 --- 18.19 19.85 22.92 --- 20.74 --- 19.64 18.54 --- LOW 20.06 21.09 19.39 19.88 20.31 22.92 23.07 23.44 21.96 22.20 20.90 20.07 HIGH 17.73 19.53 17.83 17.77 19.37 19.47 19.52 20.74 20.30 19.64 18.42 18.60 CAL YR 1982 MEAN 17.88 LOW 21.09 HIGH 15.53 WTR YR 1983 MEAN 20.25 LOW 23.44 HIGH 17.73 180026065544301. Local number, 122. LOCATION.--Lat 18°00'26", long 65°54'43". Owner: P.R. Aqueduct and Sewer Authority. Name: Maunabo Calzada. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled exploration well, diameter 4 in (10 cm). Depth 70 ft (21.3 m). DATUM.--Altitude of land-surface datum is about 28.5 ft (8.7 m) above mean sea level. Measuring point: Top of shelter floor, 1.4 ft (0.43 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--December 1971 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 2.24 ft (0.68 m) below land-surface datum, July 8, 1976; lowest measured, 12.38 ft (3.77 m) below-land surface datum, Aug. 12, 1977. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Nov. 8 c7.02 Feb. 11 c10.04 May 12 c11.12 Aug. 9 c8.72 Dec. 16 c9.17 Mar. 15 c10.90 June 27 c 7.94 Sept. 13 c8.32 Jan. 19 c9.09 Apr. 15 c11.55 July 12 c 8.19 c Pumping nearby well. 255 GROUND-WATER LEVELS RIO HUMACAO TO RIO SECO BASINS 180010066004501. Local number, 125. LOCATION.--Lat 18°00'10", long 66°00'45". Owner: P.R. Aqueduct and Sewer Authority. Name: Patillas STP. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 16 in (41 cm), cased 0-45 ft (0-13.7 m); cased 12 in (30 cm) 0-49 ft (0-14.9 m), perforated 49-81 ft (14.9 -24.7 m). Depth 90 ft (27.4 m). DATUM.--Altitude of land-surface datum is about 48 ft (14.6 m) above mean sea level. Measuring point: Bottom edge of 0.75 in (1.90 cm) pipe in concrete pump base, 1.0 ft (0.30 m) above land-surface datum. REMARKS.--Observation well. Water levels affected by pumping nearby well. PERIOD OF RECORD.--January 1976 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 12.83 ft (3.91 m) below land-surface datum, June 17, 1981; lowest measured, a52.98 ft (a16.15 m) below land-surface datum, May 24, 1979. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Nov. 10 a48.20 Mar. 15 a48.90 June 23 17.28 Aug. 4 a48.78 Dec. 16 a47.30 Apr. 5 a48.95 July 12 a47.35 Sept. 13 a48.37 Feb. 10 a48.87 May 13 a48.30 RIO SALINAS TO RIO JACAGUAS BASINS 175658066155401. Local number, 1. LOCATION.--Lat 17°56'58", long 66°15'54". Owner: P.R. Aqueduct and Sewer Authority. Name: Mar Negro. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Bored unused artesian well, diameter 3 in (8 cm). Depth 23 ft (7.0 m). DATUM.--Altitude of land-surface datum is about 3 ft (0.91 m) above mean sea level. Measuring point: Top of 1.5 in (3.8 cm) pipe fitting, 3.2 ft (0.98 m) above land-surface datum. REMARKS.--Observation well. Water levels affected by pumpage of nearby well. PERIOD OF RECORD.--September 1959 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, +1.83 ft (+0.56 m) above land-surface datum, Dec. 2, 1970; lowest measured, 3.60 ft (1.10 m) below land-surface datum, July 7, 1977. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 18 0.19 Jan. 14 0.69 Apr. 8 0.71 July 15 +0.22 Nov. 16 0.51 Feb. 10 0.80 May 6 0.00 Aug. 4 0.14 Dec. 10 0.33 Mar. 11 0.39 June 28 0.30 Sept. 13 +0.03 175851066174601. Local number, 8. LOCATION.--Lat 17°58'51", long 66°17'46". Owner: P.R. Aqueduct and Sewer Authority. Name: Salinas 1. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 16 in (41 cm) to 13 in (33 cm); cased 16 in (41 cm) 0-32 ft (0-9.8 m), 13 in (33 cm) 25-120 ft (7.6-36.6 m); perforated 25-120 ft (7.6-36.6 m). Depth 125 ft (38.1 m). DATUM.--Altitude of land-surface datum is about 29 ft (8.8 m) above mean sea level. Measuring point: Top of 1.0 in (2.54 cm) pipe in pump base, 1.2 ft (0.37 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--September 1959 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 11.95 ft (3.64 m) below land-surface datum, Dec. 14, 1960; lowest measured, 42.95 ft (13.09 m) below land-surface datum, Dec. 9, 1975. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 18 a27.92 Jan. 14 a28.03 Apr. 8 a28.92 July 15 a26.69 Nov. 16 a31.87 Feb. 10 a27.72 May 6 a25.45 Aug. A a24.50 Dec. 10 a32.68 Mar. 11 a28.52 June 28 a26.45 Sept. 13 a24.58 + Above land-surface datum. a Pumping. 256 GROUND-WATER LEVELS RIO SALINAS TO RIO JACAGUAS BASINS 175823066241801. Local number, 10. LOCATION.--Lat 17°58'23", long 66°24'18". Owner: P.R. Aqueduct and Sewer Authority. Name: Santa Isabel 1. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 13 in (0.33 m), cased 0-200 ft (0-61.0 m), perforated 128-200 ft (39.0-61.0 m). Depth 202 ft (61.6 m). DATUM.--Altitude of land-surface datum is about 36 ft (11.0 m) above mean sea level. Measuring point: Airline hole in pump base, 1.4 ft (0.43 m) above land-surface datum. REMARKS.--Observation well. Water levels affected by pumpage of nearby well. PERIOD OF RECORD.--September 1958 to April 1972. February 1974 to September 1976. November 5, 1979 to August 9, 1982 (discontinued). EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 5.82 ft (1.77 m) below land-surface datum, Dec. 14, 1960; lowest measured, 55.34 ft (16.9 m) below land-surface datum, June 24, 1974. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1979 TO SEPTEMBER 1982 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Nov. 5, 1979 24.00 July 8, 1980 30.02 July 16, 1981 30.25 Mar. 30, 1980 26.98 Feb. 25, 1980 25.02 Aug. 7 36.20 Aug. 17 30.10 Apr. 20 26.64 Mar. 17 26.15 Feb. 10, 1981 40.98 Nov. 2 28.64 May 11 26.31 Apr. 9 31.80 Mar. 10 38.25 Dec. 23 23.18 June 1 25.41 29 27.66 Apr. 20 40.17 Jan. 20, 1982 25.45 July 13 28.87 May 9 29.90 June 10 30.50 Feb. 25 22.38 Aug. 9 26.63 June 10 37.16 180044066153401. Local number, 18. LOCATION.--Lat 18°00'44", long 66°15'34". Owner: P.R. Aqueduct and Sewer Authority. Name: Cocos. AQUIFER.--Alluvium of Quaternary Age and undifferentiated rocks of Cretaceous Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 16 to 12 in (41 to 30 cm), cased 16 in (41 cm) 0-40 ft (0-12-2 m), 12 in (30 cm) 0-53 ft (0-16.2 m), perforated 32-53 ft (9.8-16.2 m). Depth 125 ft (38.1 m). DATUM.--Altitude of land-surface datum is about 140 ft (42.7 m) above mean sea level. Measuring point: Top of 1.0 in (2.54 cm) pipe in pump base, 1.25 ft (0.38 cm) above land-surface datum. REMARKS.--Observation well. Water level affected by nearby pumpage. PERIOD OF RECORD.--September 1959 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 14.67 ft (4.47 m) below land-surface datum, Sept. 20, 1960; lowest measured, 79.17 ft (24.13 m) below land-surface datum, June 19, 1968. WATER LEVEL, IN FEET BELOW LAND SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 18 22.06 Jan. 14 24.09 Apr. 8 30.49 July 15 19.76 Nov. 16 22.15 Feb. 10 28.10 May 6 23.11 Aug. 4 20.30 Dec. 10 20.80 Mar. 11 29.42 June 28 20.47 Sept. 13 22.29 180023066175301. Local number, 19. LOCATION.--Lat 18°00'23", long 66°17'53". Owner: U.S. Army. Name: Theater 1. AQUIFER.--Volcanic rocks of Cretaceous Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 16 to 11 in (41 to 28 cm), cased 16 in (41 cm) 0-64 ft (0-19.5 m), 11 in 0-80 ft (0-24.4 m), perforated 16-64 ft (4.9-19.5 m). Depth 150 ft (45.7 m) reported, 86 ft (26.2 m) measured. DATUM.--Altitude of land-surface datum is about 140 ft (42.7 m) above mean sea level. Measuring point: Top of 1.0 in (2.54 cm) casing liner, 0.85 ft (0.26 m) above land-surface datum. After Apr. 8, 1983, top of 4.0 in (10.1 cm) flat cap on new concrete slab, 3.6 ft (1.10 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--December 1958 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 39.38 ft (12.00 m) below land-surface datum, Oct. 15, 1979; lowest, measured, 79.15 ft (24.12 m) below land-surface datum, Oct. 10, 1973. .35 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 18 53.54 Jan. 14 62.33 Apr. 8 57.41 July 15 53.89 Nov. 16 54.53 Feb. 10 56.30 May 6 53.23 Aug. 4 55.50 Dec. 10 54.78 Mar. 11 56.50 June 28 54.7.0 Sept. 13 46.83 257 GROUND-WATER LEVELS RIO SALINAS TO RIO JACAGUAS BASINS 175829066232201. Local number, 87. LOCATION.--Lat 17°58'29", long 66°23'22". 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 (34.1 m). DATUM.--Altitude of land-surface datum is about 35.32 ft (10.77 m) above mean sea level. Measuring point: Bottom of clean-out shelter door, 2.5 ft (0.76 m) above land-surface datum. Prior to August 1981, top of recorder shelter floor, 4.0 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, 8.45 ft (2.58 m) below land-surface datum, Dec. 10, 1970; lowest 49.18 ft (14.99 m) below land-surface datum, July 27, 1974. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 28.91 31.49 30.74 31.37 34.11 32.11 31.88 29.87 28.40 27.93 26.30 26.01 2 28.77 31.96 30.49 31.16 33.89 32.79 31.85 29.79 28.37 28.50 26.30 26.01 3 28.66 32.29 31.16 31.28 33.84 32.97 32.00 29.80 28.37 28.59 26.31 25.97 4 28.51 32.50 30.46 32.75 33.08 33.42 31.97 29.40 28.29 28.56 26.34 25.94 5 28.63 32.60 30.63 32.48 33.35 33.26 32.07 29.18 28.24 28.46 26.65 25.89 6 28.70 32.35 31.77 32.10 33.33 32.60 32.23 29.10 27.99 28.42 26.75 25.93 7 28.74 32.83 32.15 32.57 33.52 33.01 32.32 29.11 28.02 28.42 26.71 25.95 8 28.77 32.81 32.34 32.91 34.19 34.17 32.31 29.08 28.01 28.33 26.75 25.96 9 28.85 33.02 32.53 32.84 34.38 33.15 32.34 28.93 28.01 28.28 26.80 25.95 10 28.75 33.14 32.77 32.62 34.25 32.84 32.38 28.92 28.05 28.22 27.06 25.96 11 28.69 33.25 32.72 32.56 34.20 32.67 32.30 28.90 28.03 28.13 27.27 25.93 12 28.95 33.21 32.62 32.51 34.17 32.49 32.31 28.87 28.16 28.16 27.41 25.95 13 28.95 33.16 32.56 32.47 34.03 32.29 32.42 28.95 28.03 28.11 27.29 26.02 14 29.04 32.39 32.57 32.51 34.08 32.11 32.58 28.79 28.07 28.10 27.27 26.09 15 30.33 31.73 32.62 32.72 33.84 32.08 32.51 28.52 28.08 28.11 27.22 26.17 16 30.20 32.69 32.58 32.75 33.92 32.04 32.46 28.44 27.95 28.12 27.50 26.22 17 30.65 32.66 32.67 32.68 33.86 31.90 32.37 28.39 27.82 28.02 27.30 26.22 18 30.68 32.90 33.26 32.83 33.91 31.88 32.14 28.39 27.76 27.85 27.23 26.24 19 30.72 33.02 33.28 33.02 33.62 31.79 31.55 28.38 27.66 27.80 27.24 26.23 20 30.76 31.64 32.68 33.47 32.71 31.70 31.45 28.37 27.54 27.75 27.25 26.31 21 30.85 31.80 32.79 33.64 33.22 31.57 31.24 28.36 27.81 27.67 27.04 26.37 22 30.99 31.80 33.16 33.71 33.60 32.42 30.49 28.41 27.84 27.04 26.76 26.39 23 31.17 32.09 32.18 33.74 32.93 31.84 30.41 28.36 27.89 27.31 26.57 26.46 24 30.79 31.21 32.95 33.68 33.83 32.56 30.32 28.41 27.83 26.90 26.45 26.63 25 31.03 30.84 31.28 33.72 33.63 32.25 30.22 28.43 27.89 26.94 26.34 27.05 26 31.33 30.94 30.83 33.76 32.55 31.96 30.16 28.41 27.93 27.17 26.30 27.16 27 31.49 31.32 30.70 33.29 32.26 31.98 30.06 28.47 27.88 27.14 26.23 27.24 28 31.43 30.88 31.10 33.93 32.08 31.88 29.86 28.44 27.86 27.11 26.21 27.32 29 31.63 30.71 31.27 34.04 --- 32.88 29.80 28.42 27.90 26.70 26.08 27.61 30 31.74 31.06 32.47 34.25 32.06 29.77 28.37 27.90 26.58 26.06 27.76 31 31.71 --- 31.59 34.19 31.94 --- 28.40 --- 26.44 26.07 LOW 31.74 33.25 33.28 34.25 34.38 34.17 32.58 29.87 28.40 28.59 27.50 27.76 HIGH 28.51 30.71 30.46 31.16 32.08 31.57 29.77 28.36 27.54 26.44 26.06 25.89 CAL YR 1982 MEAN 27.84 LOW 33.28 HIGH 23.28 WTR YR 1983 MEAN 30.17 LOW 34.38 HIGH 25.89 180052066305001. Local number, 88. LOCATION.--Lat 18°00'52", long 66°30'50". Owner: Luce and Co. Name: Hacienda Potala. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 19 in (48 cm). Depth 143 ft (43.6 m). DATUM.--Altitude of land-surface datum is about 15 ft (4.6 m) above mean sea level. Measuring point: Top of shelter floor, 2.20 ft (0.67 m) above land-surface datum. REMARKS.--Observation well. Water levels affected by pumpage of nearby well. Station discontinued, Jan. 1,1973. P:.activated, Apr. 15, 1976. PERIOD OF RECORD.--May 1968, January 1973; April 1976 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 4.50 ft (1.37 m) below land-surface datum; Feb. 26, 1971; lowest measured, 37.89 ft (11.55 m) below land-surface datum, July 16, 1968. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 12 16.51 Jan. 6 c27.00 Apr. 14 c28.14 July 8 14.28 Nov. 15 c28.24 Feb. 9 c28.37 May 3 17.30 Aug. 4 c21.25 Dec. 8 17.55 Mar. 9 20.62 June 28 14.17 Sept. 13 c22.72 c Pumping nearby well 258 GROUND-WATER LEVELS RIO SALINAS TO RIO JACAGUAS BASINS 175822066134801. Local number, 124. LOCATION.--Lat 17°58'22", long 66°13'48". Owner: P.R. Aqueduct and Sewer Authority. Name: Coqui 2. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 16 to 12 in (40 to 30 cm), cased 16 in (40 cm) 20-40 ft (6.1-12.2 m), 12 in (30 cm) 2-20 ft (0.61-6.1 m), perforated 20-118 ft (6.1-36.0 m). Depth 118 ft (36.0 m). DATUM.--Altitude of land-surface datum is about 26 ft (7.9 m) above mean sea level. Measuring point: Airline hole in pump base, 2.2 ft (0.67 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--April 24, 1975 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, a9.25 ft (a2.82 m) below land-surface datum, Nov. 29, 1979; lowest measured, a54.70 ft (a16.67 m) below land-surface datum, July 7, 1977. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 18 a31.92 Jan. 14 a18.16 Apr. 8 a42.75 July 15 a17.68 Nov. 16 a31.88 Feb. 10 a19.63 May 6 a44.73 Aug. 4 a15.61 Dec. 10 a20.65 Mar. 11 a36.43 June 28 a29.29 Sept. 13 a14.49 175750066225800. Local number, 144. LOCATION.--Lat 17°57'50", long 66°22'58". Owner: P.R. Aqueduct and Sewer Authority. Name: Jauca south well, site 1. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 8 in (20 cm), cased 0-50 ft (0-15.2 m), perforated 45-50 ft (13.7-15.2 m). Depth 50 ft (15.2 m). DATUM.--Altitude of land-surface datum is about 15.98 ft (4.87 m) above mean sea level. Measuring point: Hole on side of 8 in (20 cm) casing, 3.2 ft (0.98 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--September 1980 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 9.48 ft (2.89 m) below land-surface datum, Jan. 20, 1982; lowest measured, 11.90 ft (3.63 m) below land-surface datum, Feb. 9, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1979 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Sept. 11, 1980 10.20 July 16, 1981 11.20 June 9, 1982 9.56 Feb. 9, 1983 11.90 30 10.47 Aug. 17 10.72 July 13 9.63 Mar. 9 11.80 Oct. 9 10.47 Sept. 10 10.47 Aug. 9 10.25 Apr. 14 11.88 Nov. 12 10.70 Dec. 23 9.90 Sept. 2 10.40 May 6 10.57 Dec. 10 10.92 Jan. 20, 1982 9.48 Oct. 14 10.30 June 28 10.60 Feb. 10, 1981 11.32 Feb. 25 10.10 Nov. 15 10.78 July 8 10.53 Mar. 10 11.40 Mar. 30 10.72 Dec. 8 10.78 Aug. 4 10.59 May 12 11.72 Apr. 20 10.35 Jan. 6, 1983 10.02 Sept. 13 10.20 June 10 11.50 May 11 9.86 175750066225801. Local number, 145. LOCATION.--Lat 17°57'50", long 66°22'58". Owner: P.R. Aqueduct and Sewer Authority. Name: Jauca north well, site 1. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 8 in (20 cm), cased 0-250 ft (0-76.2 m), perforated 245-250 ft (74.7-76.2 m). Depth 250 ft (76.2 m). DATUM.--Altitude of land-surface datum is about 16.11 ft (4.91 m) above mean sea level. Measuring point: Hole on side of 8 in (20 cm) casing, 1.5 ft (0.46 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--September 1980 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 9.50 ft (2.90 m) below land-surface datum, Jan. 20, 1982; lowest measured, 13.23 ft (4.03 m) below land-surface datum, Jan. 6, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1979 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Sept. 30, 1980 11.10 Aug. 17, 1981 10.76 June 9, 1982 10.04 Feb. 9, 1983 12.03 Oct. 9 10.92 Sept. 10 10.72 July 13 10.07 Mar. 9 11.94 Nov. 12 11.42 Dec. 23 9.92 Aug. 9 10.69 Apr. 14 12.29 Dec. 10 11.84 Jan. 20, 1982 9.50 Sept. 2 10.72 May 6 11.14 Mar. 10, 1981 12.43 Feb. 25 10.22 Oct. 14 10.69 June 28 10.78 May 12 12.17 Mar. 30 10.84 Nov. 15 11.15 July 8 10.63 June 10 10.60 Apr. 29 10.83 Dec. 8 11.22 Aug. 4 10.71 July 16 10.80 May 11 10.37 Jan. 6, 1983 13.23 Sept. 13 10.70 a Pumping. 259 GROUND-WATER LEVELS RIO SALINAS TO RIO JACAGUAS BASINS 175734066233300. Local number, 146. LOCATION.--Lat 17°57'34", long 66°23'33". Owner: P.R. Aqueduct and Sewer Authority. Name: Hacienda Alomar west well, site 3. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 8 in (20 cm), cased 0-70 ft (0-21.3 m), perforated 65-70 ft (19.8-21.3 m). Depth 70 ft (21.3 m). DATUM.--Altitude of land-surface datum is about 18.74 ft (5.71 m) above mean sea level. Measuring point: Hole on side of 8 in (20 cm) casing, 2.5 ft (0.76 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--June 1981 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 8.32 ft (2.54 m) below land-surface datum, June 3, 1981; lowest measured, 12.49 ft (3.81 m) below land-surface datum, Aug. 17, 1981. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1980 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level June 3, 1981 8.32 Feb. 25, 1982 10.65 Sept. 2, 1982 10.37 Apr. 14, 1983 12.17 10 8.98 Mar. 30 11.59 Oct. 14 9.49 May 6 11.06 July 16 11.53 Apr. 20 10.69 Nov. 15 10.18 June 28 8.96 Aug. 17 12.49 May 11 9.93 Dec. 8 9.92 July 8 9.55 Sept. 10 11.35 June 9 10.27 Jan. 6, 1983 10.30 Aug. 4 10.38 Dec. 23 10.17 July 13 10.06 Feb. 9 9.78 Sept. 13 11.00 Jan. 20, 1982 9.09 Aug. 9 10.84 Mar. 9 10.64 175734066233301. Local number, 147. LOCATION.--Lat 17°57'34", long 66°23'33". Owner: P.R. Aqueduct and Sewer Authority. Name: Hacienda Alomar east well, site 3. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 8 in (20 cm), cased 0-250 ft (0-76.2 m), perforated 245-250 ft (74.7-76.2 m). Depth 250 ft (76.2 m). DATUM.--Altitude of land-surface datum is about 18.80 ft (5.73 m) above mean sea level. Measuring point: Top of 8 in (20 cm) casing, 3.6 ft (1.10 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--June 1981 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 13.55 ft (4.13 m) below land-surface datum, July 13, 1982; lowest measured, 14.88 ft (4.54 m) below land-surface datum, April 14, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1980 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level June 3, 1981 14.69 Feb. 25, 1982 13.93 Sept 2, 1982 13.93 Apr. 14, 1983 14.88 10 14.62 Mar. 30 14.62 Oct. 14 13.74 May 6 14.21 July 16 14.66 Apr. 20 14.26 Nov. 15 14.07 June 28 13.89 Aug. 17 14.38 May 11 13.79 Dec. 8 14.22 July 8 13.78 Sept. 10 14.35 June 9 13.62 Jan. 6, 1983 14.55 Aug. 4 13.99 Dec. 23 13.95 July 13 13.55 Feb. 9 14.69 Sept. 13 13.92 Jan. 20, 1982 13.66 Aug. 9 14.30 Mar. 9 14.54 175756066244000. Local number, 148. LOCATION.--Lat 17°57'56", long 66°24'40". Owner: P.R. Aqueduct and Sewer Authority. Name: Playa Santa Isabel east well, site 2. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 8 in (20 cm), cased 0-250 ft (0-76.2 m), diameter 2 in (5 cm), cased 0-200 ft (0-61.0 m), perforated 195-200 ft (59.4-61.0 m), concreted 200-250 ft (61.0-76.2 m). Depth 200 ft (61.0 m). DATUM.--Altitude of land-surface datum is about 21.20 ft (6.46 m) above mean sea level. Measuring point: Hole side of 8 in (20 cm) casing, 2.8 ft (0.85 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--January 1981 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 12.82 ft (3.91 m) below land-surface datum, Dec. 23, 1981; lowest measured, 29.45 (8.98 m) below land-surface datum, Jan. 13, 1981. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1980 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water level Date level Date level Date level Date Jan. Feb. Mar. 13, 1981 10 10 29.45 22.08 22.98 Dec. 23, 1981 Jan. 20, 1982 Feb. 25 12.82 13..09 13.91 Aug. 11, 1982 Sept. 15 Oct. 14 15.04 16.26 15.91 Mar. Apr. May 9, 1983 14 3 18.60 17,43 15.90 May June July Aug. 12 10 16 17 21.02 15.10 15.69 15.14 Mar. 30 Apr. 20 May 11 June 9 15.16 15.60 15.22 13.34 Nov. Dec. Jan. Feb. 15 8 6, 1983 9 17.54 17.69 17.69 18.12 June 28 July 8 Aug. 4 Sept. 13 14.50 14.30 14.22 13.96 Sept. 10 15.33 July 13 14.36 260 GROUND-WATER LEVELS RIO SALINAS TO JACAGUAS BASINS 175756066244001. Local number, 149. LOCATION.--Lat 17°57'56", long 66°24'40". Owner: P.R. Aqueduct and Sewer Authority. Name: Playa Santa Isabel west well, site 2. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 8 in (20 cm), cased 0-250 ft (0-76.2 m), diameter 2 in (5 cm), cased 0-250 ft (0-76.2 m), perforated 245-250 ft (74.7-76.2 m), concreted 200-250 ft (61.0-76.2 m). Depth 250 ft (76.2 m). DATUM.--Altitude of land-surface datum is about 21.20 ft (6.46 m) above mean sea level. Measuring point: Hole side of 8 in (20 cm) casing, 2.8 ft (0.85 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--January 1981 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 12.07 ft (3.68 m) below land-surface, Dec. 23, 1981; lowest measured, 26.92 ft (8.21 m) below land-surface datum, Jan. 13, 1981. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1980 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Jan. 13, 1981 26.92 Dec. 23, 1981 12.07 Aug. 11, 1982 14.48 Mar. 9, 1983 17.08 Feb. 10 21.84 Jan. 20, 1982 13.20 Sept. 15 14.03 Apr. 14 16.47 Mar. 10 21.57 Feb. 25 12.83 Oct. 14 15.70 May 3 13.89 May 12 18.60 Mar. 30 13.93 Nov. 15 15.70 June 28 13.28 June 10 14.58 Apr. 20 14.82 Dec. 8 17.48 July 8 12.81 July 16 15.73 May 11 12.90 Jan. 6, 1983 16.20 Aug. 4 12.92 Aug. 17 14.25 June 9 12.49 Feb. 9 18.60 Sept. 13 12.50 Sept 10 14.28 July 13 14.44 RIO INABON TO RIO LOCO BASINS 175922066495901. Local number, 16. LOCATION.--Lat 17°59'22", long 66°49'59". Owner: Sucesi6n Lluveras. Name: Central San Francisco. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused artesian well, diameter 20 in (51 cm). Depth 185 ft (56.4). DATUM.--Altitude of land-surface datum is about 30 ft (9.1 m) above mean sea level. Measuring point: Top of shelter's wooden base, 4.06 ft (1.24 m) above land-surface datum. REMARKS.--Recording observation well (Nov. 9, 1960 to Mar. 23, 1965). Water levels affected by pumpage of nearby wells. PERIOD OF RECORD.--November 1960 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 1.43 ft (0.44 m) below land-surface datum, Dec. 22, 1960; lowest measured, 35.76 ft (10.90 m) below land-surface datum, Mar. 7, 1975. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 12 5.14 Jan. 5 5.14 Apr. 12 5.58 Aug. 15 6.57 Nov. 9 5.28 Feb. 1 5.57 May 5 4.43 Sept. 14 6.56 Dec. 10 4.26 Mar. 14 5.37 July 8 5.64 180057066361101. Local number, 21. LOCATION.--Lat 18°00'57", long 66°36'11". Owner: P.R. Aqueduct and Sewer Authority. Name: Alhambra. AQUIFER.--Ponce Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled public supply artesian well, diameter 20 in (51 cm), cased 300 ft (91.4 m), perforated 80-300 ft (24.4-91.4 m). Depth 300 ft (91.4 m). DATUM.--Altitude of land-surface datum is about 53 ft (16.2 m) above mean sea level. Measuring point: Bottom edge 1.5 in (3.8 cm) pipe in concrete pump base, 0.7 ft (0.21 m) below land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--November 1958 to August 10, 1972; January 17, 1975 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 17.43 ft (5.31 m) below land-surface datum, Dec. 14, 1960; lowest measured, 97.61 ft (29.75 m) below land-surface datum, Aug. 8, 1967. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 12 a72.74 Jan. 17 a80.57 Apr. 12 a77.60 Jul. 6 31.33 Nov. 15 a72.34 Feb. 2 a74.92 May 9 a65.36 Sept. 14 a75.20 Dec. 7 a74.00 Mar. 16 a77.40 June 3 a71.27 a Pumping. 261 GROUND-WATER LEVELS RIO INABON TO RIO LOCO BASINS 180150066474901. Local number, 27. LOCATION.--Lat 18°01'50", long 66°47'49". Owner: P.R. Aqueduct and Sewer Authority. Name: Quebradas. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 16 to 12 in (41 to 30 cm), cased 16 in (41 cm) 0-40 ft (0-12.2 m), 12 in (30 cm) 0-120 ft (0-36.6 m), perforated 40-120 ft (12.2-36.6 m). Depth 120 ft (36.6 m). DATUM.--Altitude of land-surface datum is about 59 ft (18.0 m) above mean sea level. Measuring point: Top of 1.0 in (2.54 cm) pipe in pump base, 1.1 ft (0.34 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--November 1958 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 25.72 ft (7.84 m) below land-surface datum, Oct. 8, 1959; lowest measured, 75.1 ft (22.89 m) below land-surface datum, June 27, 1972. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 12 a35.83 Jan. 17 a32.01 Apr. 12 a37.59 July 6 a28.70 Nov. 12 a28.52 Feb. 2 a32.28 May 9 a32.54 Aug. 3 a29.90 Dec. 13 a30.48 Mar. 16 a37.10 June 7 a30.69 Sept. 14 a31.15 180110066473501. Local number, 74. LOCATION.--Lat 18°01'10", long 66°47'35". Owner: P.R. Aqueduct and Sewer Authority. Name: Guayanilla. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 16 in (41 cm), cased 0-103 ft (0-31.4 m), perforated 39-103 ft (11.9-31.4 m). Depth 102 ft (31.1 m). DATUM.--Altitude of land-surface datum is about 34 ft (10.4 m) above mean sea level. Measuring point: Airline hole in pump base, 3.0 ft (0.91 m) above land-surface datum. REMARKS.--Observation well. Drilled to 195 ft (59.44 m), plugged back to 102 ft (31.1 m). PERIOD OF RECORD.--August 1960 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 8.56 ft (2.61 m) below land-surface datum, Oct. 21, 1960; lowest measured, 90.50 ft (27.58 m) below land-surface datum, Aug. 13, 1976. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 12 al5.30 Jan. 17 a15.37 Apr. 12 al6.00 July 6 a15.34 Nov. 12 a15.48 Feb. 2 a15.55 May 5 a15.44 Aug. 3 a15.35 Dec. 13 a15.25 Mar. 16 a15.40 June 7 a15.39 Sept. 14 a15.22 180058066502701. Local number, 131. LOCATION.--Lat 18°00'58", long 66°50'27". Owner: Union Carbide Corporation. Name: Yauco 1 or UCC 2. AQUIFER.--Alluvium of Quaternary Age and limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled observation well, casing slotted 20-145 ft (6.1-44.2 m), open hole below 145 ft (44.2 m). Depth 156 ft (47.6 m) DATUM.--Altitude of land-surface datum is about 66 ft (20.1 m) above mean sea level. Measuring point: Top of 3 in (0.08 m) pipe, 2.5 ft (0.76 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--August 1972 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 0.46 ft (0.14 m) below land-surface datum; June 14, 1979; lowest measured, 44.95 ft (13.70 m) below land-surface datum, May 20, 1974. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 12 7.52 Jan. 4 7.50 Apr. 12 10.99 July 8 7.72 Nov. 9 7.24 Feb. 1 8.19 May 5 5.35 Aug. 5 8.58 Dec. 10 6.92 Mar. 14 7.18 June 7 7.13 Sept. 14 9.22 a Pumping. 262 GROUND-WATER LEVELS RIO INABON TO RIO LOCO BASINS 180133066503301. Local number, 132. LOCATION.--Lat 18°01'33", long 66°50'33". Owner: Pittsburg Plate Glass 4. Name: Yauco 2. AQUIFER.--Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled observation well, cased 20 in (51 cm) 0-20 ft (0-6.1 m), 12 in (30 cm) perforated pipe 20-84 ft (6.1-25.6 m), 10 in (25 cm) perforated pipe 84-190 ft (25.6-57.9 m). Depth 190 ft (57.9 m). Datum.--Altitude of land-surface datum is about 75 ft (22.9 m) above mean sea level. 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, +0.12 ft (+0.04 m) below land-surface datum, July 19, 1979; lowest, 36.91 ft (11.25 m) below land-surface datum, June 27, 1974. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER TEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAT OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 7.40 6.60 6.03 6.87 3.69 10.58 11.72 7.76 7.24 6.37 8.13 8.34 2 7.14 6.57 6.13 6.92 8.83 10.68 11.77 7.65 7.23 6.42 8.22 8.48 3 7.19 6.49 6.20 7.10 8.96 10.76 11.81 7.54 7.19 6.39 8.24 8.34 4 7.21 6.55 6.27 7.18 9.06 10.84 11.89 7.41 7.19 6.24 8.24 8.35 5 7.19 6.71 6.33 7.19 9.09 10.92 12.02 7.42 7.19 6.16 8.37 8.45 6 7.21 6.61 6.38 7.10 9.19 11.03 12.13 7.42 7.17 6.27 8.30 8.48 7 7.19 6.63 6.44 7.14 9.36 11.15 12.22 7.46 7.15 6.32 8.26 8.54 8 7.24 6.80 6.48 7.19 9.48 11.28 12.30 7.49 7.10 6.34 8.39 8.58 9 7.16 6.77 6.41 7.25 9.57 11.40 12.31 7.54 7.07 6.41 8.52 8.59 10 7.13 6.75 6.35 7.38 9.63 11.50 12.37 7.58 6.98 6.46 8.59 8.49 11 7.11 6.57 6.25 7.42 9.75 11.61 12.40 7.54 6.94 6.52 8.59 8.48 12 7.11 6.47 6.21 7.43 9.72 11.51 12.60 7.50 6.91 6.58 8.65 8.65 13 7.10 6.22 6.19 7.36 9.80 10.74 12.74 7.50 6.82 6.65 8.57 8.73 14 7.10 6.30 6.37 7.38 9.91 20.39 12.85 7.54 6.79 6.71 8.52 8.78 15 7.16 6.32 6.45 7.40 9.88 10.69 12.88 7.55 6.74 6.77 8.67 8.84 16 7.10 6.42 6.46 7.43 10.05 10.69 12.87 7.58 6.52 6.87 8.63 8.82 17 7.07 6.14 6.50 7.48 10.15 10.70 12.84 7.61 6.16 6.88 8.70 8.67 18 7.15 6.15 6.38 7.54 10.17 10.74 12.80 7.65 6.05 6.98 8.20 8.65 19 7.12 6.04 6.42 7.58 10.11 10.77 12.56 7.42 5.95 7.01 8.23 8.75 20 6.96 6.06 6.26 7.64 10.19 10.80 12.42 7.32 6.10 7.05 8.25 8.76 21 6.91 5.97 6.34 7.72 10.24 10.86 11.18 7.26 6.05 7.04 8.28 8.75 22 6.91 5.99 6.56 7.79 10.24 10.91 9.72 7.09 5.96 7.14 8.07 8.79 23 6.85 6.03 6.62 7.79 10.24 10.99 9.58 7.15 6.04 7.17 8.03 8.73 24 6.84 6.08 6.68 7.85 10.30 11.08 9.45 7.18 6.16 7.29 8.02 8.54 25 6.88 6.17 6.54 7.87 10.38 11.14 9.35 7.19 6.21 7.53 8.00 8.49 26 6.91 6.21 6.56 7.92 10.44 11.22 9.22 7.13 6.25 7.58 8.01 8.63 27 6.90 6.22 6.73 8.00 10.49 11.31 9.08 7.17 6.24 7.70 8.05 8.70 28 6.87 6.22 6.78 8.07 10.55 11.41 8.72 7.16 6.30 7.80 8.10 8.69 29 6.84 6.14 6.83 8.15 --- 11.47 8.07 7.13 6.31 7.92 8.12 8.74 30 6.78 6.16 6.90 8.27 11.56 7.87 7.11 6.34 7.94 8.16 8.81 31 6.64 --- 6.95 8.47 11.69 --- 7.18 --- 8.01 8.19 --- LOW 7.40 6.80 6.95 8.47 10.55 20.39 12.88 7.76 7.24 8.01 8.70 8.84 HIGH 6.64 5.97 6.03 6.87 8.69 10.58 7.87 7.09 5.95 6.16 8.00 8.34 CAL YR 1982 MEAN 9.58 LOW 13.72 HIGH 5.97 WTR YR 1983 MEAN 8.13 LOW 20.39 HIGH 5.95 180120066503201. Local number, 134. LOCATION.--Lat 18°01'20", long 66°50'32". Owner: Union Carbide Corporation. Name: Yauco 4 or UCC 1. AQUIFER.--Alluvium of Quaternary Age and limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled observation well, casing slotted 20-140 ft (6.1-42.7 m) open hole 140-163 ft (42.7-49.7 m). Depth 163 ft (49.7 m). DATUM.--Altitude of land-surface datum is about 87 ft (26.5 m) above mean sea level. Measuring point: Top of 3 in (0.08 m) pipe, 3.4 ft (1.04 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--July 1972 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 7.90 ft (2.41 m) below land-surface datum; June 14, 1979; lowest measured, 37.84 ft (11.53 m) below land-surface datum, June 27, 1974. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 12 11.35 Jan. 4 11.18 Apr. 12 14.87 July 8 10.77 Nov. 9 10.98 Feb. 1 12.12 May 5 10.92 Aug. 5 12.00 Dec. 10 10.78 Mar. 14 13.40 June 7 11.29 Sept. 14 11.05 + Above land-surface datum. 263 GROUND-WATER LEVELS RIO INABON TO RIO LOCO BASINS 175950066354201. Local number, 141. LOCATION.--Lat 17°59'50", long 66°35'42". Owner: P.R. Aqueduct and Sewer Authority. Name : Restaurada 8A. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused public supply well, diameter 16 to 10 in (41 to 25 cm), cased 16 in (41 cm) 2-20 ft (0.6-6.1 m), perforated 20-130 ft (6.1-39.6 m), 10 in (25 cm) 128-165 ft (39.0-50.3 m), perforated. Depth 165 ft (50.3 m). DATUM.--Altitude of land-surface datum is about 24 ft (7.3 m) above mean sea level. Measuring Point: Bottom edge of hole on side of casing, 1.9 ft (0.58 m) above land-surface datum, 26.15 ft (7.97 m) above mean sea level. REMARKS.--Recording observation well. PERIOD OF RECORD.--October 1981 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level, 15.65 ft (4.77 m) below land-surface datum, Aug. 30, 1983; lowest, 28.59 ft (8.714 m) below land-surface datum, July 9, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 22.29 18.75 19.92 24.22 23.67 20.92 19.06 19.18 18.01 16.36 2 3 4 5 22.27 22.19 22.20 22.31 18.66 18.65 18.77 18.28 20.16 20.24 20.38 20.33 24.41 24.62 24.72 24.68 23.58 23.49 23.44 23.58 20.70 20.54 20.40 20.32 19.53 19.28 19.18 19.17 19.16 19.01 18.92 18.75 18.01 18.03 18.04 18.06 16.32 16.28 16.09 15.97 6 7 8 9 10 22.53 22.45 22.80 22.77 22.62 --- 20.81 20.89 20.91 20.97 18.30 17.89 18.15 18.25 18.31 20.23 20.18 20.25 20.00 20.27 24.52 24.38 24.46 24.58 24.13 23.70 23.35 23.26 23.29 23.31 20.80 21.01 20.51 20.34 20.43 19.15 19.65 20.30 20.53 20.58 18.27 18.11 18.50 18.60 18.13 18.04 17.98 17.92 17.86 17.90 15.83 15.89 15.92 15.93 15.95 11 12 13 14 15 22.55 22.62 --- 20.81 20.56 20.43 21.12 21.04 18.46 18.12 18.30 18.40 18.37 20.48 20.56 20.53 20.37 20.64 23.70 23.85 23.24 22.94 23.41 23.26 23.46 23.63 24.17 24.44 20.58 20.69 20.63 20.37 20.12 20.36 20.10 19.96 20.02 19.87 18.40 18.10 18.06 18.20 18.41 17.88 17.55 17.64 17.63 17.57 15.91 15.87 15.91 15.95 16.08 16 17 18 19 20 21.50 21.59 21.67 21.65 21.40 18.25 18.22 18.39 18.45 18.65 23.19 23.59 23.84 23.83 23.72 23.09 23.15 23.48 23.77 23.70 24.50 24.48 23.57 23.38 23.11 19.91 19.83 19.81 19.84 19.80 19.28 19.03 18.93 19.20 18.82 18.45 18.46 18.46 18.45 18.50 17.51 17.42 17.20 17.12 17.07 16.64 16.58 16.87 17.02 17.13 21 22 23 24 25 - - 21.58 21.70 21.80 19.17 19.11 18.88 18.97 18.83 18.83 19.44 23.65 23.66 23.98 24.14 24.27 23.63 23.84 23.30 23.76 23.94 20.49 21.54 21.40 21.22 21.03 19.65 19.68 19.55 19.62 19.66 19.18 19.45 19.56 19.58 18.93 18.51 18.51 18.51 18.39 18.24 16.89 16.09 15.94 15.89 15.81 17.14 17.49 17.66 17.68 26 27 28 29 30 31 18.94 18.84 19.02 19.09 18.99 18.87 19.89 20.15 20.33 20.25 19.90 19.87 24.26 24.06 23.98 --- 23.82 23.68 23.71 23.59 23.67 23.75 21.08 21.18 21.25 21.33 21.12 --- 19.48 19.25 19.07 19.04 18.93 19.32 18.58 18.97 19.11 19.17 19.21 18.13 18.11 18.06 18.05 18.06 18.02 16.29 16.49 16.07 15.88 15.98 16.47 17.59 17.42 16.88 16.75 16.71 LOW 20.33 24.27 24.72 24.50 21.01 20.58 19.18 18.06 HIGH 17.89 19.92 22.94 20.49 18.93 18.58 18.02 15.81 RIO GUANAJIBO BASIN 180933067050801. Local number 40. LOCATION.--Lat 18°09'33", long 67°05'08". Owner: P.R. Aqueduct and Sewer Authority. Name: Rosario. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled public supply artesian well, diameter 16 to 12 in (41 to 30 cm), cased 16 in (41 cm) 0-30 ft (0-9.1 m) 12 in (30 cm) 0-60 ft (0-18.3 m), perforated 12 in (30 cm) 10-60 ft (3.0-18.3 m). Depth 105 ft (32.0 m). DATUM.--Altitude of land-surface datum is about 164 ft (50.0 m) above mean sea level. Measuring point: Lower edge of 0.75 in (1.90 cm) pipe at pump base, 2.7 ft (0.82 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--July 1960 to November 1971; May 1973; March 1974 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 0.20 ft (0.06 m) below land-surface datum, Aug. 3, 1983; lowest measured, 37.30 ft (11.37 m) below land-surface datum, May 7, 1973. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 7 a13.54 Jan. 12 13.00 Apr. 14 a13.93 July 13 a13.16 Nov. 10 a12.62 Feb. 9 9.30 May 12 a14.75 Aug. 3 a 0.20 Dec. 27 a14.23 Mar. 17 a14.18 June 9 a12.55 Sept. 8 a14.12 a Pumping. 264 GROUND-WATER LEVELS RIO GUANAJIBO BASIN 181018067091601. Local number, 43. LOCATION.--Lat 18°10'18", long 67°09'16". Owner: Mayaguez Sugar Co. Name: Central Rochelaise. AQUIFER.--Volcanic rocks of Cretaceous Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 12 in (30 cm), cased 0-45 ft (0-13.7 m), perforated 0-45 ft (0-13.7 m). Depth 80 ft (24.4 m). DATUM.--Altitude of land-surface datum is about 7 ft (2.1 m) above mean sea level. Measuring point: Top of 12 in (30 cm) casing, 1.9 ft (0.58 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--August 1959 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, +0.50 ft (+0.15 m) above land-surface datum, Nov. 20, 1979; lowest measured, 2.70 ft (0.82 m) below land-surface datum, Apr. 15, 1970. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Date Water level Date Water level Date Water level Date Water level Oct. Nov. Dec. 6 10 22 +0.48 0.00 0.00 Jan. 13 Feb. 8 Mar. 17 0.00 0.00 +0.40 Apr. May June 14 12 9 0.08 +0.20 0.00 July Aug. Sept. 12 3 8 0.00 0.00 0.00 180132067033801. Local number, 143. LOCATION.--Lat 18°01'32", long 67° ,03'38". Owner: Pedro P. Vivoni. Name : Vivoni, Hacienda Amistad. AQUIFER.--Limestone of unknown age. WELL CHARACTERISTICS.--Drilled unused irrigation well, diameter 12 in (30 cm). Depth 200 ft (61.0 m). DATUM.--Altitude of land-surface datum is about 52.5 ft (16.0 m) above mean sea level. 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, 38.00 ft (11.58 m) below land-surface datum, Sept. 19-20, 1982; lowest, 39.34 ft (11.99 m) below land-surface datum, Apr. 10, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 38.89 38.80 38.61 38.57 38.94 39.20 39.21 39.22 38.92 38.98 39.09 39.05 2 38.89 38.76 33.61 38.56 38.92 39.22 39.25 39.23 38.94 39.03 39.10 39.07 3 38.89 38.75 33.60 38.56 38.91 39.22 39.22 39.21 38.93 39.03 39.10 39.12 4 38.89 38.75 38.58 38.57 38.98 39.23 39.22 39.20 38.93 39.04• 39.11 39.11 5 38.91 38.77 38.59 38.58 38.96 39.25 39.21 39.20 38.96 39.04 39.15 39.06 6 38.91 38.74 38.59 38.57 39.01 39.24 39.25 39.24 38.98 39.02 39.17 39.05 7 38.87 38.75 38.56 38.58 39.01 39.25 39.28 39.22 38.99 39.03 39.15 39.05 8 38.85 38.75 38.58 38.56 39.05 39.23 39.28 39.19 38.96 39.04 39.16 39.08 9 38.84 38.76 38.56 38.58 39.03 39.24 39.32 39.21 38.98 38.94 39.18 39.11 10 38.84 38.76 38.57 38.56 39.06 39.25 39.34 39.24 38.79 38.95 39.19 39.12 11 38.84 38.77 38.55 38.58 39.11 39.23 39.29 39.22 38.79 38.97 39.12 39.11 12 38.85 38.77 38.53 38.57 39.16 39.20 39.26 39.21 38.79 38.99 39.11 39.12 13 38.89 38.77 38.54 38.60 39.14 39.19 39.26 39.22 38.78 39.00 39.08 39.13 14 33.92 38.79 33.60 38.64 39.12 39.20 39.27 39.14 38.78 38.99 39.08 39.16 15 38.89 38.79 38.62 38.60 39.10 39.17 39.29 39.12 38.75 38.98 39.10 39.17 16 38.92 38.79 38.59 38.64 39.12 39.13 39.28 39.13 38.77 38.98 39.10 39.16 17 38.89 38.72 38.58 38.66 39.14 39.11 39.27 39.10 38.81 39.01 39.09 39.18 18 38.90 38.75 38.56 38.67 39.13 39.15 39.21 39.12 38.85 39.02 39.10 39.20 19 38.86 38.70 38.59 38.70 39.08 39.16 39.24 39.04 38.86 39.03 39.10 39.24 20 38.82 38.69 38.58 38.72 39.14 39.16 39.26 39.04 38.86 39.07 39.12 39.21 21 33.77 38.66 38.59 38.73 39.16 39.19 39.23 39.01 38.89 39.04 39.12 39.26 22 38.78 38.66 38.59 38.79 39.15 39.21 39.26 38.97 38.90 39.02 39.10 39.25 23 38.78 38.69 38.58 38.79 39.17 39.20 39.26 38.98 38.92 39.08 39.12 39.25 24 33.78 38.70 38.57 38.84 39.17 39.21 39.25 38.97 38.91 39.10 39.11 39.26 25 38.83 38.74 38.59 38.84 39.17 39.21 39.24 38.92 38.92 39.09 39.09 39.23 26 38.84 38.68 38.55 38.85 39.20 39.27 39.24 38.90 38.95 39.07 39.08 39.26 27 38.81 38.66 38.55 38.92 39.18 39.27 39.23 38.92 38.94 39.07 39.07 39.27 28 38.78 38.61 38.56 38.89 39.20 39.26 39.21 38.92 38.97 39.04 39.05 39.27 29 38.78 38.62 38.55 38.92 --- 39.26 39.22 38.92 38.96 39.07 39.07 39.26 30 38.81 38.66 38.56 38.90 39.25 39.22 38.90 38.99 39.06 39.06 39.32 31 38.82 --- 38.59 38.89 39.23 --- 38.90 --- 39.08 39.04 --- LOW 38.92 38.80 33.62 38.92 39.20 39.27 39.34 39.24 38.99 39.10 39.19 39.32 HIGH 38.77 38.61 38.53 38.56 38.91 39.11 39.21 38.90 38.75 38.94 39.04 39.05 CAL YR 1982 MEAN 38.90 LOW 39.26 HIGH 33.00 WTR YR 1983 MEAN 38.97 LOW 39.34 HIGH 38.53 + Above land-surface datum. GROUND-WATER LEVELS RIO YAGUEZ AND RIO GRANDE DE ARASCO BASINS 181233067083201. Local number, 45. LOCATION.--Lat 18°12'33", long 67°08'32". Owner: Cerveceria India, Inc. Name: Well 1, Mayaguez. AQUIFER.--Alluvium of Quaternary Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 12 in (30 cm), cased 0-82 ft (0-25.0 m). Depth 82 ft (25.0 m). DATUM.--Altitude of land-surface datum is about 23 ft (7.0 m) above mean sea level. Measuring point: Top of wood cover, 0.9 ft (0.27 m) above land-surface datum. REMARKS.--Observation well. Affected by nearby pumping. PERIOD OF RECORD.--1960 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 9.41 ft (2.87 m) below land-surface datum, Sept. 15, 1977; lowest measured, 29.97 ft (9.13 m) below land-surface datum, Jan. 20, 1966. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 6 12.14 Jan. 13 11.51 Apr. 14 11.85 July 12 14.88 Nov. 10 12.63 Feb. 8 12.00 May 12 12.46 Aug. 3 13.96 Dec. 21 12.86 Mar. 17 12.23 June 9 13.33 Sept. 7 12.87 181522067090901. Local number, 53. LOCATION.--Lat 18°15'22", long 67°09'09". Owner: P.R. Ports Authority. Name: Mayaguez Airport. AQUIFER.--Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled public supply water-table well, diameter 8 in (20 cm), cased 0-114 ft (0-34.8 m), perforated 82-114 ft (25.0-34.8 m), open hole 114-353 ft (34.8-107.6 m). Depth 353 ft (107.6 m). DATUM.--Altitude of land-surface datum is about 20 ft (6.1 m) above mean sea level. Measuring point: Slot in pump base, 0.4 ft (0.12 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--October 1960 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 0.96 ft (0.29 m) below land-surface datum, Oct. 5, 1978; lowest measured, 8.70 ft (2.65 m) below land-surface datum, Feb. 14, 1979. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATION Water Water Water Water Date level Date level Date level Date level Oct. 5 5.58 Jan. 12 5.90 Apr. 14 5.85 July 12 4.63 Nov. 10 5.40 Feb. 8 5.10 May 12 5.42 Aug. 3 2.10 Dec. 21 5.05 Mar. 17 5.48 June 6 3.88 Sept. 7 2.00 265 266 GROUND-WATER LEVELS RIO CULEBRINAS BASIN 182228067113301. Local number, 58. LOCATION.--Lat 18°22'38", long 67°11'33". Owner: P.R. Aqueduct and Sewer Authority. Name: Aguada. AQUIFER.--Limestone of Tertiary Age. WELL CHARACTERISTICS.--Drilled public supply artesian well, diameter 20 in (51 cm) to 12 in (30 cm), cased 20 in (51 cm) 0-40 ft (0-12.2 m), 12 in (30 cm) 0-60 ft (0-18.3 m), perforated 40-60 ft (12.2-18.3 m) Depth 160 ft (48.8 m). DATUM.--Altitude of land-surface datum is about 30 ft (9.1 m) above mean sea level. Measuring point: Lower edge of 0.75 in (1.90 cm) pipe in pump base, 1.90 ft (0.58 m) above land-surface datum. REMARKS.--Observation well. Piezometric head measured for highest water level. PERIOD OF RECORD.--January 1960 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, +0.81 ft (+0.25 m) above land-surface datum, Sept. 12, 1975; lowest measured, 83.53 ft (25.46 m) below land-surface datum, Aug. 7, 1974. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 6 0.40 Jan. 12 1.20 Apr. 14 3.83 July 12 1.35 Nov. 10 0.27 Feb. 8 2.20 May 12 1.80 Aug. 3 1.58 Dec. 21 1.34 Mar. 17 3.05 June 6 0.89 Sept. 7 0.58 182018066593201. Local number, 83. LOCATION.--Lat 18°20'18", long 66°59'32". Owner: P.R. Water Resources Authority. Name: San Sebasti5n. AQUIFER.--Volcanic rock of Eocene Age. WELL CHARACTERISTICS.--Drilled observation well, diameter 6 in (15 cm). Depth 300 ft (91.4 m). DATUM.--Altitude of land-surface datum is about 230 ft (70.1 m) above mean sea level. Measuring point: Top of casing, 2.40 ft (0.73 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD.--May 1967 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 21.95 ft (6.69 m) below land-surface datum, Apr. 15, 1976; lowest measured, 40.20 ft (12.25 m) below land-surface datum, July 21, 1970. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Oct. 5 28.67 Jan. 11 29.04 Apr. 13 30.71 July 12 28.53 Nov. 5 28.74 Feb. 8 29.75 May 4 29.38 Aug. 3 30.55 Dec. 21 28.90 Mar. 16 30.22 June 6 26.88 Sept. 1 27.96 + Above land-surface datum. Surface- Water Records for U.S. Virgin Islands 268 65°05' 65°00' 55' 64°501 18°24' ST. THOMAS Goa 18°20' 0 1 ti 2 3 4 MILES 18°22' 64°50' 45' 64°40' ST. JOHN 18°18' 0 1 C) 64°50' ST. CROIX 2 3 4 MILES 45' 40' 64°35' 17°45' 17°40'— 0 1 2 3 4 MILES 11111 1 Figure 27.--Surface-water stations in the U.S. Virgin Islands. 269 ST. THOMAS, U.S. VIRGIN ISLANDS 50252000 BONNE RESOLUTION GUT AT BONNE RESOLUTION, ST. THOMAS, VI LOCATION.--Lat 18°21'57", long 64°57'34", Hydrologic Unit 21020001, on right bank near Hull Bay Road, 0.5 mi (0.8 km) upstream from Atlantic Ocean, and 2.5 mi (4.02 km) northwest of Fort Christian, Charlotte Amalie. DRAINAGE AREA.--0.49 sq mi (1.27 sq 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 concrete control. Altitude of gage is 280 ft (85.3 m), from topographic map. December 1962 to February 1967 at site about 100 ft (30.5 m) downstream at different datum. March 1979 to April 1981 at site about 100 ft (30.5 m) upstream at different datum. REMARKS. - -Records poor. AVERAGE DISCHARGE.--5 years (1964-66, 1980, 1983), 0.24 cu Ws-(0.0068 cu m/s), 6.62 in/yr (168.1 mm/yr), 173 acre-ft/yr (0.213 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 1,650 cu ft/s (46.7 cu m/s) Apr. 18, 1983, gage height, 7.00 ft (2.134 m), from floodmarks, from rating curve extended above 1.0 cu ft/s (0.03 cu m/s) on basis of critical-depth analysis and slope-area measurement of peak flow; no flow at times in most years. EXTREMES FOR WATER YEARS 1979, 80, 83.--Peak discharges above base of 50 cu ft/s (1.42 cu m/s) and maximums (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) May 30, 1979 1500 122 3.46 3.16 0.963 May 27, 1980 1830 86 2.44 2.82 0.860 Aug. 30 2400 121 3.43 3.15 0.960 May 28 1000 115 3.26 3.09 0.942 Sept. 4 0700 *218 6.17 3.92 1.195 Oct. 6 1430 92 2.60 2.87 0.875 Sept. 7 1900 110 3.12 3.04 0.926 Apr. 18, 1983 1315 *1,650 46.7 7.00 2.134 Nov. 23 1000 122 3.46 3.16 0.963 June 17 1945 281 7.96 2.88 0.878 Nov. 23 2400 *169 4.79 3.56 1.085 June 18 0100 600 17.0 4.17 1.271 No flow at times in each year. DISCHARGE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1978 TO SEPTEMBER 1979 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .02 .04 .12 .05 .03 .16 2 .02 .C4 .07 .05 .02 .12 3 .02 .04 .06 .04 .02 .22 4 .02 .04 .05 .04 .02 50 5 .03 .04 .05 .03 .02 30 6 .03 .04 .05 .04 .02 2.0 7 .03 .04 .04 .04 .02 6.8 8 .02 .03 .04 .04 .03 .02 1.8 9 .02 .04 .04 .04 .02 .02 .25 10 .02 .02 .13 .04 .02 .02 .12 11 .04 .03 .11 .04 .02 .02 .08 12 .03 .02 .05 .04 .02 .01 .06 13 .03 .02 .04 .04 .02 .01 .05 14 .03 .03 .05 .04 .02 .02 .05 15 .03 .03 .07 .04 .02 .02 .04 16 .03 .03 .07 .04 .03 .01 .04 17 .03 .03 .09 .03 .03 .01 .04 18 .25 .04 .41 .03 1.2 .02 .04 19 .04 .04 .85 .03 .33 .02 .04 20 .03 .04 .09 .02 .04 .02 .04 21 .02 .04 .08 .02 .02 .01 .04 22 .02 .04 .05 .02 .02 .03 .04 23 .02 .04 .05 .02 .02 .03 .04 24 .02 .03 .05 .02 .02 .04 .03 25 .02 .05 .07 .03 .01 .02 .04 26 .02 .04 .07 .04 .01 .02 .04 27 .02 .04 .07 .02 .01 .02 .04 28 .02 .04 .07 .05 .02 .02 .04 29 .12 .04 .09 .08 .02 .02 .04 30 .05 .04 13 .07 .02 4.1 .05 31 .03 --- 1.2 --- .02 5.3 --- TOTAL .97 17.12 1.28 2.28 9.98 92.35 MEAN .032 .55 .043 .074 .32 3.08 MAX .05 13 .12 1.2 5.3 50 MIN .02 .04 .02 .01 .01 .03 CFSM .07 1.12 .09 .15 .65 6.29 IN. .07 1.30 .10 .17 .76 7.00 AC-FT 1.9 34 2.5 4.5 20 183 50252000 BONNE RESOLUTION GUT AT BONNE RESOLUTION, ST. THOMAS, VI--Continued 270 DAY OCT DISCHARGE, NOV DEC IN CUBIC FEET PER JAN FEB SECOND, WATER YEAR OCTOBER MEAN VALUES MAR APR MAY 1979 TO SEPTEMBER 1980 JUN JUL AUG SEP 1 .04 .10 .05 .05 .05 .01 .01 .01 .01 .01 .00 .01 2 .05 .10 .06 .05 .05 .01 .01 .01 .01 .01 .00 .01 3 .02 .05 .05 .05 .05 .01 .01 .01 .01 .01 .00 .01 4 .04 .05 .05 .05 .04 .01 .01 .01 .01 .01 .01 .01 5 .02 .05 .05 .05 .04 .01 .01 .01 .01 .01 .01 .64 6 .02 .03 .05 .05 .06 .01 .01 .01 .01 .01 .01 .03 7 .02 .05 .05 .05 .04 .01 .01 .01 .01 .01 .01 .02 8 .02 .20 .05 .06 .04 .01 .01 .02 .01 .01 .01 .02 9 .0.2 .10 .05 .05 .03 .01 .02 .01 .01 .01 .01 1.3 10 .02 .03 .05 .05 .03 .01 .01 .01 .01 .01 .01 .06 11 .05 .07 .05 .05 .02 .01 .00 .01 .01 .01 .01 .04 12 .05 .06 .04 .05 .02 .01 .01 .C2 .01 .01 .01 .04 13 .05 .05 .05 .05 .02 .01 .01 .C2 .01 .01 .01 .06 14 .05 .05 .05 .04 .02 .01 .01 .01 .01 .01 .01 .04 15 .63 .05 .04 .04 .03 .01 .00 .01 .01 .01 .01 .04 16 .10 .05 .04 .04 .02 .01 .01 .00 .01 .01 .01 .04 17 .05 .07 .04 .04 .02 .01 .01 .00 .01 .01 .01 .03 18 .02 .07 .05 .04 .02 .01 .01 .00 .01 .01 .01 .03 19 .02 .07 .05 .04 .03 .01 .01 .00 .01 .01 .01 .03 20 .02 .07 .05 .04 .03 .01 .01 .00 .01 .01 .01 .03 21 .02 .07 .04 .04 .03 .01 .01 .01 .01 .01 .01 .04 22 .05 .10 .04 .04 .03 .01 .01 .01 .01 .01 .01 .04 23 .02 19 .05 .04 .02 .01 .02 .01 .01 .01 .01 .03 24 .04 7.9 .05 .04 .02 .01 .01 .01 .01 .01 .01 .02 25 .06 1.6 .05 .04 .02 .01 .01 .01 .01 .00 .01 .02 26 .04 .16 .04 .04 .02 .01 .01 .01 .01 .00 .02 .02 27 .02 .09 .04 .04 .02 .01 .01 2.9 .01 .00 .01 .03 28 .03 .08 .04 .04 .02 .01 .01 8.2 .01 .00 .01 .04 29 .03 .07 .04 .05 .02 .01 .01 .03 .01 .01 .01 .03 30 .02 .06 .05 .05 --- .01 .01 .02 .01 .00 .01 .14 31 .20 --- .05 .05 .01 --- .02 --- .00 .01 --- TOTAL 1.84 30.55 1.46 1.41 .86 .31 .30 11.41 .30 .25 .29 2.90 MEAN .059 1.02 .047 .045 .030 .010 .010 .37 .010 .008 .009 .097 MAX .63 19 .06 .06 .06 .01 .02 8.2 .01 .01 .02 1.3 MIN .02 .03 .04 .04 .02 .01 .00 .00 .01 .00 .00 .01 CFSM .12 2.03 .10 .09 .06 .02 .02 .76 .02 .02 .02 .20 IN. .14 2.31 .11 .11 .07 .02 .02 .86 .02 .02 .02 .22 AC-FT 3.6 61 2.9 2.8 1.7 .6 .6 23 .6 .5 .6 5.8 WTR YR 1980 TOTAL 51.38 MEAN .14 MAX 19 MIN .00 CFSM .29 IN 3.93 AC-FT 103 DISCHARGE. IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1780 TC SEPTEMBER 1981 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .04 .02 .02 .02 .02 .02 .04 2 .03 .02 .02 .02 .02 .02 .04 3 .02 .02 .02 .01 .02 .02 .04 4 .05 .02 .02 .01 .02 .29 .04 5 .76 .02 .02 .03 .01 .13 .03 6 4.8 .02 .03 .04 .02 .05 .04 7 .21 .02 .04 .02 .02 .06 .05 .02 .02 .02 .02 .05 9 .04 .02 .02 .02 .02 .05 10 .02 .02 .02 .02 .02 .04 11 .02 .02 .02 .02 .02 .04 12 .02 .02 .03 .02 .02 .04 13 .02 .02 .02 .02 .02 .04 14 .02 .02 .03 .02 .02 .04 15 .02 .02 .03 .02 .02 .04 16 .02 .02 .02 .02 .02 .04 17 .02 .02 .02 .02 .02 .04 18 .02 .02 .02 .02 .02 .04 19 .02 .02 .02 .02 .02 .04 20 .45 .02 .01 .02 .02 .05 21 .02 .02 .01 .02 .03 .05 22 .02 .02 .02 .02 .02 .05 23 .02 .02 .02 .02 .02 .04 24 .02 .02 .02 .03 .02 .03 25 .02 .02 .02 .03 .02 .03 26 .02 .02 .02 .02 .02 .31 27 .02 .02 .01 .85 .02 .05 28 .02 .02 .01 .05 .02 .05 29 .02 .02 .01 .29 --- .04 30 .03 .02 .01 .04 .04 31 .02 --- .02 .03 .03 TOTAL 6.88 .60 .62 1.81 .56 1.86 MEAN .22 .020 .020 .058 .020 .060 MAX 4.8 .02 .04 .85 .03 .31 MIN .02 .02 .01 .01 .01 .02 CFSM .45 .04 .04 .12 .04 .12 IN. .52 .05 .05 .14 .04 .14 AC-FT 14 1.2 1.2 3.6 1.1 3.7 CAL YR 1980 TOTAL 26.13 MEAN .071 MAX 8.2 MIN .00 CFSM .15 IN 1.98 AC-FT 52 --- 271 ST. THOMAS, U.S. VIRGIN ISLANDS 50252000 BONNE RESOLUTION GUT AT BONNE RESOLUTION, ST. THOMAS, VI--Continued DISCHARGE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1981 TO SEPTEMBER 1982 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .01 .02 .06 .03 2 .01 .02 .09 .03 3 .03 .03 .06 .03 4 .01 .03 .09 .03 5 .01 .03 .09 .03 6 .02 .02 .09 .03 7 .03 .02 .09 .04 8 .03 .02 .09 .03 9 .03 .02 .06 .01 10 .03 .02 .06 .01 11 .04 .02 .06 .02 12 .04 .01 .04 .11 13 .04 .02 .04 1.2 14 .04 .02 .06 .08 15 .03 .03 .06 .04 16 .03 .01 .06 .03 17 .03 .01 .04 .03 18 .02 .01 .03 .03 19 .03 .03 .03 .03 20 .02 .02 .03 .04 21 .02 .02 .03 .05 22 .02 .09 .04 .04 23 .02 .04 .04 .04 24 .02 .04 .04 .03 25 .02 .06 .04 .03 26 .02 .02 .06 .04 .04 27 .02 .01 .06 .03 .05 28 .01 .02 .06 .03 .06 29 .01 .02 .09 .03 .04 30 .01 .02 .09 .04 .05 31 .01 --- .09 .04 TOTAL .72 1.11 1.63 2.31 MEAN .C24 .036 .053 .077 MAX .04 .09 .09 1.2 MIN .01 .01 .03 .01 CFSM .05 .07 .11 .16 IN. .05 .08 .12 .18 AC-FT 1.4 2.2 3.2 4.6 DISCHARGE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FE8 MAR APR MAY JUN JUL AUG SEP 1 .08 .04 .01 .14 .04 .03 .02 .07 .06 .05 .13 .07 2 .08 .04 .02 .07 .04 .02 .03 .06 .04 .06 .15 .07 3 .02 .06 .01 .03 .04 .02 .03 .06 .04 .05 .08 .10 4 .01 .07 .01 .02 .04 .03 .04 .06 .05 .06 .07 .09 5 .02 .05 .02 .02 .04 .03 .05 .06 .05 .18 .07 .09 6 .02 .04 .02 .02 .04 .03 .04 .10 .06 .18 .06 .07 7 .03 .04 .02 .02 .04 .05 .05 .14 .05 1.2 .06 .07 8 .03 .04 .02 .01 .05 .04 .02 .06 .03 .15 .06 .06 9 .02 .07 .02 .02 .06 .03 .03 .11 .03 .10 .05 .05 10 .00 .09 .02 .01 .06 .04 .04 .10 .05 .07 .04 .06 11 .02 .09 .02 .02 .04 .03 .04 .09 .04 .06 .04 .07 12 .02 .08 .02 .02 .03 .13 .05 .07 .03 .06 .03 .10 13 .02 .03 .07 .03 .03 .03 .04 .10 .05 .06 .04 .10 14 .02 .05 .06 .03 .02 .02 .03 .09 .05 .07 .04 .06 15 .02 .06 .15 .04 .02 .02 .03 .09 .05 .08 .05 .08 16 .01 .06 .10 .03 .02 .02 .03 .08 .06 .08 .04 .07 17 .01 .06 .05 .03 .03 .03 .08 .09 13 .06 .05 .08 18 .11 .06 .03 .03 .03 .03 169 .25 24 .07 .07 .09 19 .24 .07 .03 .03 .03 .02 1.9 .26 .33 .08 .06 .05 20 .11 .06 2.3 .02 .02 .02 .72 .42 .22 .05 .06 .06 21 .04 .04 .21 .01 .27 .02 .46 .14 .14 .09 1.1 .07 22 .05 .04 .10 .02 .02 .02 .29 .11 .10 .09 .09 .08 23 .03 2.9 .06 .02 .02 .03 .20 .11 .08 .08 .06 .08 24 .02 .10 .06 .03 .02 .04 .15 .12 .07 .31 .06 .08 25 .02 .05 .06 .04 .02 .04 .13 .09 .06 .08 .05 .08 26 .02 .03 .17 .06 .02 .04 .11 .07 .05 .06 .04 .02 27 .02 .02 1.9 .04 .02 .04 .07 .C7 .11 .06 .08 .03 28 .02 .01 5.3 .03 .03 .04 .07 .07 .06 .06 .60 .03 29 .03 .02 .25 .04 --- .05 .06 .08 .05 .07 .10 .02 30 .03 .02 .13 .04 .05 .06 .06 .05 .07 .08 .02 31 .03 --- .24 .04 .01 --- .07 --- .16 .07 --- TOTAL 1.20 4.39 11.48 1.01 1.14 1.05 173.37 3.35 39.06 3.90 3.58 2.00 MEAN .039 .15 .37 .033 .041 .034 5.80 .11 1.30 .13 .12 .067 MAX .24 2.9 5.3 .14 .27 .13 169 .42 24 1.2 1.1 .10 MIN .00 .01 .01 .01 .02 .01 .02 .06 .03 .05 .03 .02 CFSM .08 .31 .76 .07 .08 .07 11.8 .22 2.65 .27 .25 .14 IN. .09 .33 .87 .08 .09 .03 13.17 .25 2.96 .30 .27 .15 AC-FT 2.4 8.7 23 2.0 2.3 2.1 345 6.6 77 7.7 7.1 4.0 WTR YR 1983 TOTAL 246.03 MEAN .67 MAX 169 MIN .00 CFSM 1.37 IN 18.64 AC-FT 488 272 ST. THOMAS, U.S. VIRGIN ISLANDS 50252000 BONNE RESOLUTION GUT AT BONNE RESOLUTION, ST. THOMAS, VI--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--MARCH TO SEPTEMBER 1983 WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMMOS) (DEG C) (CFS) (UMHOS) (DEG C) MAR, 22 1200 .02 2424 24.5 SEP. 2E 1044 .04 1381 25.5 JUL. 20 1055 .05 1343 26.5 273 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 left 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 sq mi (7.69 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1963 to April 1969, October 1978 to September 1980, June 1982 to current year. GAGE.--Water-stage recorder and V-notch weir in concrete control. Altitude of gage is 40 ft (12.2 m), from topographic map. REMARKS.--Records poor. Since about 1975, low flow augmented by discharges from sewage plant. AVERAGE DISCHARGES.--6 years (1964-68, 1979), 0.53 cu ft/s (0.015 cu m/s), 2.43 in/yr (61.7 mm/yr) 385 acre-ft/yr (0.47 cu hm/yr). --7 years (1964-68, 1979-80), 0.63 cu ft/s (0.018 cu m/s), 2.88 in/yr (73.2 mm/yr), 456 acre-ft/yr (0.56 cu hm/yr). --8 years (1964-68, 1979-80, 1983), 1.07 cu ft/s (0.030 cu m/s), 4.89 in/yr (124 mm/yr), 775 acre-ft/yr (0.96 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 9,710 cu ft/s (275 cu m/s) Apr. 18, 1983, gage height, 11.09 ft (3.380 m), from floodmark, from rating curve extended above 500 cu ft/s (14.2 cu m/s) on basis of slope area measurement and step-backwater analysis; no flow many days from 1963 to 1969. EXTREMES FOR WATER YEARS 1979-80, 1982-83.--Peak discharges above base of 100 cu ft/s (2.83 cu m/s) and maximums (*): Discharge Gage height Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Date Time (cu ft/s) (cu m/s) (ft) (m) Oct. 26, 1978 1030 373 10.6 4.77 1.454 Sept. 13, 1982 0145 178 5.04 4.25 1.295 May 18, 1979 2100 122 3.46 4.01 1.222 Nov. 11 0415 254 7.19 4.49 1.368 May 30 0700 207 5.86 4.35 1.326 Feb. 21, 1983 0345 141 3.99 4.10 1.250 Aug. 30 2230 250 7.08 4.48 1.366 Apr. 18 Unknown *9,710 275 11.09 3.380 Sept. 4 2000 *2,500 70.8 7.32 2.231 May 13 0700 647 18.3 5.30 1.615 Oct. 15 0930 110 3.12 3.95 1.204 May 20 0345 504 14.3 5.01 1.527 Nov. 23 2400 *546 15.5 5.10 1.554 June 18 0130 276 7.82 4.55 1.387 Aug. 7, 1980 2030 134 3.79 4.07 1.240 Minimum discharges, .03 cu ft/s (.0008 cu m/s) Apr. 7, 1979; .02 cu ft/s (.0006 cu m/s) July 5, 25, 1980; .01 cu ft/s (.0003 cu m/s) Apr. 2, 1983. DISCHARGE, IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1978 TC SEPTEMBER 1979 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .41 2.0 .30 .16 .13 .15 .17 .06 3.8 1.1 .30 2.4 2 .28 1.0 .87 .17 .13 .16 .15 .06 2.1 .35 .70 1.1 3 .30 .73 .57 .17 .15 .14 .14 .13 2.1 .31 .25 2.0 4 .20 .65 .57 .15 .13 .14 .16 .17 1.1 .23 .30 290 5 .23 .65 .33 .14 .13 .19 .15 .20 .80 .26 .25 200 6 .24 .60 .28 .21 .14 .14 .11 .21 .69 1.7 .22 23 7 .18 .57 .24 .21 .13 .14 .13 .14 .60 .70 .19 23 8 .21 .36 .24 .19 .16 .12 .15 .11 .52 .40 .18 16 9 10 2.2 2.2 .31 .45 .28 .35 .24 .12 .15 .16 .11 .14 .57 .13 .58 .43 1.1 .69 2.0 .60 .17 .16 10 8.0 11 .33 .33 .26 .09 .20 .15 .11 3.3 .52 .40 .16 7.1 12 .22 1.8 .26 .15 .16 .13 .17 .31 .41 .35 .15 5.5 13 .21 .62 .23 .16 .09 .10 .24 .24 .41 3.0 .15 5.6 14 6.0 1.9 .19 .17 .11 .09 .15 .26 .35 .80 .14 4.4 15 1.9 1.5 .20 .16 .13 .10 .17 .52 .36 .50 .14 3.8 16 .34 .54 .24 .15 .14 .09 .16 2.6 .35 .32 .14 3.7 17 .33 .38 .28 .15 .16 .14 .16 3.4 .33 .28 .14 3.3 18 .19 5.0 .20 .15 .15 1.2 .10 10 .31 .50 .20 3.0 19 .21 1.4 .17 .15 .14 .21 .13 9.1 .29 .35 .40 2.8 20 .21 .84 .20 .15 .14 .15 .16 1.5 .14 .70 .20 2.6 21 .17 1.0 .28 .16 .20 .13 .17 .84 .19 .30 .50 2.6 22 1.0 .47 .24 .14 .15 .13 .19 .57 .21 .33 3.5 2.4 23 1.0 .43 .26 .17 .14 .14 .20 .49 .21 .25 1.2 2.4 24 .58 .33 .30 .15 .16 .17 .17 .46 .17 .22 1.0 2.4 25 .43 .36 .23 .11 .15 .16 .19 .49 .11 .21 .90 2.1 26 66 .33 .24 .07 .13 .13 .19 .43 .20 .20 .80 2.0 27 31 .35 .21 .15 .14 .10 .19 .46 .16 .19 .70 1.9 28 2.9 .36 .21 .16 .15 .11 .16 2.5 .81 .19 .65 1.8 29 2.7 .30 .21 .13 --- 1.4 .17 2.0 4.1 .18 .60 1.8 30 1.7 .30 .24 .14 .26 .09 57 .95 .13 23 1.9 31 1.7 --- .21 .13 .20 --- 14 --- .20 18 --- TOTAL 126.07 26.01 3.89 4.75 4.05 6.72 5.13 112.56 24.08 17.30 55.39 638.6 MEAN 4.07 .87 .29 .15 .14 .22 .17 3.63 .80 .56 1.79 21.3 MAX 66 5.0 .87 .24 .20 1.4 .57 57 4.1 3.0 23 290 MIN .17 .30 .17 .07 .09 .09 .09 .C6 .11 .18 .14 1.1 CFSM 1.37 .29 .10 .05 .05 .07 .06 1.22 .27 .19 .60 7.17 IN. 1.58 .33 .11 .06 .05 .08 .06 1.41 .30 .22 .69 8.00 AC-FT 250 52 18 9.4 8.0 13 10 223 48 34 110 1270 WTR YR 1979 TOTAL 1029.55 MEAN 2.82 MAX 290 MIN .06 CFSM .95 IN 12.89 AC-FT 2040 --- --- 274 ST. THOMAS, U.S. VIRGIN ISLANDS 50276000 TURPENTINE RUN AT MARIENDAL, ST. THOMAS, VI--Continued DISCHARGE. IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1979 TO SEPTEMBER 1980 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2.1 6.2 2.0 .90 .35 .13 .10 .11 .23 .09 .09 .15 2 1.5 1.4 1.7 .80 .35 .13 .10 .13 .17 .09 .09 4.5 3 1.3 1.0 1.4 .80 .30 .13 .10 .15 .16 .09 .09 .33 4 1.4 .80 1.3 .70 .30 .20 .09 .16 .16 .13 .89 .21 5 2.0 .84 1.2 .70 .29 .40 .09 .14 .15 .14 .44 2.5 6 1.3 3.3 1.1 .70 .27 .70 .09 .14 .15 .16 .16 .31 7 1.3 1.7 1.1 .60 .26 .30 .09 .13 .17 .25 3.8 .11 8 1.1 2.6 1.0 .60 .24 .50 .09 .11 .17 .10 .54 .10 9 .95 7.8 1.0 .60 .23 .25 .09 .15 .16 .13 .24 .97 10 .34 5.5 1.0 .60 .22 .20 .09 .15 .14 .14 .20 .21 11 .73 2.0 1.0 .60 .21 .17 .10 .14 .14 .08 .16 .19 12 .73 1.3 1.0 .60 .20 .16 .12 .13 .13 .08 .16 3.7 13 .73 1.3 1.0 .50 .20 .14 .14 .24 .17 .16 .14 .65 14 .73 .88 1.0 .50 .19 .13 .11 1.6 .17 .14 .15 .33 15 17 .76 1.0 .50 .18 .12 .09 .23 .15 .14 .14 .24 16 1.8 3.2 1.0 .50 .18 .12 .08 .20 .14 .11 .15 .20 17 1.0 2.6 1.0 .50 .17 .12 .09 .21 .14 .16 .14 .20 18 .88 1.5 1.4 .50 .17 .11 .08 .19 .14 .23 .13 .17 19 .80 1.2 1.2 .50 .16 .11 .08 .16 .13 .13 .19 .15 20 .30 1.0 1.0 .50 .16 .11 .08 .15 .14 .14 .15 .20 21 .92 1.8 1.3 .50 .16 .11 .08 .15 .14 .13 .13 .21 22 .76 8.3 2.0 .50 .15 .11 .09 .14 .15 .08 .13 .16 23 .65 110 4.0 .50 .15 .10 .60 .15 .11 .08 .14 .15 24 .62 76 1.5 .40 .15 .10 .25 .16 .13 .08 .13 .14 25 1.9 17 1.0 .40 .15 .10 .18 .16 .13 .08 .16 .14 26 .69 3.0 2.0 .40 .14 .10 .14 .15 .13 .09 .14 .13 27 .65 1.7 1.3 .40 .14 .10 .11 .19 .11 .09 .15 .13 28 .76 1.3 1.1 .40 .14 .10 .14 4.1 .09 .11 .14 .12 29 .65 1.1 1.0 .40 .13 .10 .14 .52 .11 .08 .13 .12 30 .57 1.0 1.0 .40 --- .10 .09 .24 .09 .08 .17 .12 31 .76 --- .90 .35 .10 --- .21 --- .09 .15 TOTAL 47.92 268.08 40.50 16.85 5.94 5.35 3.72 10.79 4.30 3.68 14.62 16.84 MEAN 1.55 8.94 1.31 .54 .20 .17 .12 .35 .14 .12 .47 .56 MAX 17 110 4.0 .90 .35 .70 .60 4.1 .23 .25 8.8 4.5 MIN .57 .76 .90 .35 .13 .10 .08 .11 .09 .08 .09 .10 CFSM .52 3.01 .44 .18 .07 .06 .04 .12 .05 .04 .16 .19 IN. .60 3.36 .51 .21 .07 .07 .05 .14 .05 .05 .18 .21 AC-FT 95 532 80 33 12 11 7.4 21 8.5 7.3 29 33 CAL YR 1979 TOTAL 1225.08 MEAN 3.36 MAX 290 MIN .06 CFSM 1.13 IN 15.34 AC-FT 2430 WTR YR 1980 TOTAL 438.59 MEAN 1.23 MAX 110 MIN .08 CFSM .40 IN 5.49 AC-FT 870 DISCHARGE, IN CUBIC FEET PER SECOND. WATER YEAR OCTOBER 1981 TO SEPTEMBER 1982 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .26 .25 .15 2 .26 .15 .14 3 .28 .14 .14 4 .25 .15 .15 5 .13 .14 .15 6 .13 .16 .14 7 .13 .17 .12 8 .15 .46 .12 9 .16 .19 .15 10 .17 .20 .12 11 .15 .15 .18 12 .14 .16 5.0 13 .14 .35 20 14 .11 .18 2.0 15 .13 .17 .50 16 .14 .15 .15 17 .18 .13 .17 18 1.1 .15 .15 19 .20 .14 .14 20 .16 .13 .13 21 --- .15 .15 .13 22 .20 1.2 .16 .13 23 .16 .20 .15 .15 24 .15 .20 .14 .14 25 .14 .18 2.0 .13 26 .17 .17 4.5 .15 27 .15 .16 1.0 .14 28 .21 .16 .30 .20 29 .25 .31 .20 .17 30 .26 .19 .15 .20 31 --- .17 .17 TOTAL 7.46 12.64 31.34 MEAN .24 .41 1.04 MAX 1.2 4.5 20 MIN .11 .13 .12 CFSM .08 .14 .35 IN. .09 .16 .39 AC-FT 15 25 62 275 ST. THOMAS, U.S. VIRGIN ISLANDS 50276000 TURPENTINE RUN AT MARIENDAL, ST. THOMAS, VI--Continued DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .15 .13 .05 .36 .10 .07 .06 .18 .39 .57 6.6 .45 2 .14 .03 .07 .16 .10 .11 .06 .17 .55 .53 6.3 .43 3 .13 .05 .05 .13 .11 .06 .06 .17 .51 .55 2.5 .44 4 .30 .08 .05 .11 .11 .09 .07 .18 .57 .65 2.2 .50 5 .17 .11 .05 .15 .14 .13 .05 .15 .44 2.7 2.3 .44 6 .15 .15 .05 .13 .13 .09 .05 .16 .37 5.1 1.8 .45 7 .12 .11 .05 .12 .08 .07 .04 .17 .32 5.0 1.0 .97 3 .20 .07 .10 .14 .07 .06 .06 .19 .38 1.3 .80 .67 9 .12 .08 .08 .14 .07 .08 .07 .19 .33 .92 .90 .46 10 .11 .06 .13 .11 .11 .07 .05 .40 .31 .86 .70 .43 11 .20 20 .15 .12 .09 .10 .05 .72 .34 .78 .60 .44 12 .11 1.0 .14 .12 .11 .11 .04 .79 .30 .65 1.0 .43 13 .08 2.0 .10 .11 .10 .12 .06 55 .28 .64 .60 .44 14 .11 .50 .10 .11 .09 .07 .04 4.6 .85 .53 .50 .43 15 .13 .20 .11 .14 .07 .06 .05 4.5 1.4 2.5 .45 .49 16 .15 .12 .10 .14 .08 .09 .09 4.0 .59 5.3 .50 .44 17 .15 .13 .12 .14 .09 .06 .11 2.0 13 2.4 .56 .46 13 1.1 .11 .13 .11 .11 .07 1000 1.0 45 .79 .80 .49 19 1.8 .09 .13 .12 .12 .11 100 1.0 2.5 .76 .45 .49 20 1.5 .08 2.5 .11 .08 .12 10 37 1.2 .74 .40 .49 21 .22 .07 .47 .11 13 .08 5.0 5.3 .77 .60 1.2 .46 22 .15 .15 .17 .15 .34 .05 2.0 2.7 .66 .53 .60 .54 23 .17 .50 .44 .14 .11 .07 1.0 2.1 .58 .65 .45 .55 24 .14 .10 .20 .11 .08 .06 .80 1.7 .56 11 .39 .57 25 .11 .07 .15 .10 .12 .06 .50 .99 .52 3.3 .41 .66 26 .10 .06 .64 .13 .12 .09 .40 .69 .51 2.8 .43 .56 27 .10 .15 .41 .09 .13 .03 .30 .51 2.6 2.9 .61 .57 28 .11 .08 .23 .11 .07 .04 .22 .49 .74 3.0 .71 .57 29 .11 .07 .18 .14 --- .06 .19 .51 .60 3.7 .62 .53 30 .15 .06 .93 .13 .05 .17 .49 .53 2.3 .46 .56 31 .12 --- .52 .10 .07 --- .43 --- 2.9 .46 --- TOTAL 3.40 26.46 8.60 4.03 15.93 2.45 1121.59 128.43 77.70 66.95 37.30 15.41 MEAN .27 .88 .28 .13 .57 .079 37.4 4.14 2.59 2.16 1.20 .51 MAX 1.8 20 2.5 .36 13 .13 1000 55 45 11 6.6 .97 MIN .08 .05 .05 .09 .07 .04 .04 .15 .28 .53 .39 .43 CFSM .09 .30 .09 .04 .19 .03 12.6 1.39 .87 .73 .40 .17 IN. .11 .33 .11 .05 .20 .03 14.04 1.61 .97 .84 .47 .19 AC-FT 17 52 17 3.1 32 4.9 2220 255 154 133 74 31 WTR YR 1983 TOTAL 1513.35 MEAN 4.15 MAX 1000 MIN .04 CFSM 1.40 IN 18.95 AC-FT 3000 WATER-QUALITY RECORDS PERIOD OF RECORD.--MARCH TO SEPTEMBER 1983 WATER-QUALITY DATA, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOWb, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMHOS) (0EG C) (CFS) (UMHOS) (DEG C) MAR, 22 1442 .18 2350 28.0 SEP, 28 1310 .71 1980 31.0 JUL' 2C 1433 .73 1932 29.0 276 ST. JOHN, U.S. VIRGIN ISLANDS 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 sq mi (0.96 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1963 to October 1967, September 1982 to current year. GAGE.--Water-stage recorder and concrete control. Altitude of gage is 260 ft (79.2 m), from topographic map. Prior to September 1982, at datum 1.00 ft (0.305 m) higher. REMARKS.--Records poor. AVERAGE DISCHARGE.--5 years(1964-67, 1983), 0.076 cu ft/s (.002 cu m/s), 2.789 in/yr (70.8 mm/yr), 55.06 acre-ft/yr (0.068 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 946 cu ft/s (26.8 cu m/s) Apr. 18, 1983, gage height, 5.33 ft (1.625 m), from floodmark, from rating curve extended above 1.0 cu ft/s (0.028 cu m/s) on basis of stepback-water analysis and slope-area measurement of peak flow; no flow many days each year. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 10 cu ft/s (0.283 cu m/s) and maximum (*): Discharge Gage height Date Time (cu ft/s) (cu m/s) (ft) (m) Apr. 18 Unknown 946 30.3 5.33 1.624 No flow many days. DAY DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER MEAN VALUES OCT NOV DEC JAN FEB MAR APR MAY 1982 TO SEPTEMBER 1983 JUN JUL AUG SEP 1 .01 .02 .04 .02 .01 .00 .03 .04 .00 .01 .03 .01 2 .01 .02 .04 .02 .01 .00 .03 .04 .00 .00 .04 .02 3 .00 .03 .03 .01 .01 .01 .02 .04 .00 .00 .05 .02 4 .00 .01 .03 .01 .01 .02 .01 .04 .00 .00 .06 .00 5 .01 .01 .02 .01 .01 .00 .02 .04 .01 .02 .02 .00 6 .02 .03 .02 .01 .01 .00 .01 .04 .00 .03 .01 .00 7 .03 .03 .02 .01 .01 .01 .01 .04 .00 .02 .01 .00 3 .03 .03 .01 .01 .01 .01 .00 .04 .01 .04 .02 .00 9 .05 .03 .01 .00 .01 .00 .00 .02 .01 .02 .03 .00 10 .05 .04 .01 .00 .02 .00 .00 .02 .00 .02 .01 .00 11 .04 .06 .01 .00 .02 .00 .00 .02 .00 .02 .01 .00 12 .01 .04 .01 .00 .02 .00 .00 .03 .00 .02 .04 .02 13 .02 .03 .02 .00 .01 .00 .00 .C3 .00 .02 .03 .01 14 .02 .03 .01 .00 .00 .00 .00 .05 .02 .02 .03 .01 15 .04 .03 .02 .00 .00 .00 .01 .C4 .01 .02 .04 .02 16 .05 .06 .02 .00 .00 .01 .01 .03 .01 .03 .04 .01 17 .06 .06 .01 .00 .00 .02 .02 .C3 .00 .03 .07 .01 18 .02 .07 .01 .00 .00 .01 110 .02 .02 .03 .07 .01 19 .01 .08 .01 .00 .00 .01 10 .C1 .01 .03 .08 .01 20 .03 .07 .02 .00 .00 .01 .10 .01 .00 .02 .08 .02 21 .03 .07 .02 .00 .00 .01 .15 .01 .00 .01 .37 .02 22 .03 .07 .01 .00 .00 .00 .06 .03 .00 .00 .03 .03 23 .03 .90 .02 .00 .00 .00 .05 .02 .00 .00 .01 .04 24 .04 .12 .01 .01 .00 .00 .05 .04 .00 .02 .00 .05 25 .03 .05 .01 .00 .00 .00 .05 .02 .00 .01 .00 .03 26 .02 .06 .03 .00 .00 .01 .07 .00 .00 .00 .00 .01 27 .02 .09 .01 .00 .00 .01 .06 .00 .03 .01 .00 .01 28 .02 .02 .02 .00 .00 .02 .04 .00 .05 .01 1.2 .01 29 .02 .04 .02 .01 .02 .04 .00 .02 .01 .08 .00 30 .02 .05 .01 .01 .01 .04 .00 .01 .01 .04 .00 31 .03 --- .01 .00 .01 --- .00 --- .02 .03 --- TOTAL .80 2.25 .54 .13 .16 .20 120.88 .75 .21 .50 2.53 .37 MEAN .026 .075 .017 .004 .006 .006 4.03 .024 .007 .016 .082 .012 MAX .06 .90 .04 .02 .02 .02 110 .C5 .05 .04 1.2 .05 MIN .00 .01 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 CFSM .07 .20 .05 .01 .02 .02 10.9 .07 .02 .04 .22 .03 IN. .08 .23 .05 .01 .02 .02 12.12 .08 .02 .05 .25 .04 AC-FT 1.6 4.5 1.1 .3 .3 .4 240 1.5 .4 1.0 5.0 .7 MTR YR 1983 TOTAL 129.32 MEAN .35 MAX 110 MIN .00 CFSM .95 IN 12.97 AC-FT 257 WATER-QUALITY RECORDS PERIOD OF RECORD.--MARCH TO SEPTEMBER 1983 WATER-QUALITY DATA, WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 DATE TIME STREAMFLOW, INSTANTANEOUS SPECIFIC CON- DUCTANCE TEMPERA- TURE DATE TIME STREAMFLOW, INSTANTANEOUS SPECIFIC CON- DUCTANCE TEMPERA- TURE (CFS) (UMHOS) (DEG C) (US) (umHos) (DEG C) MAR, 23 1025 .01 2272 24.5 JUL, 21 0850 .01 2352 26.0 JUN, 30 1014 .01 2352 26.0 SEP, 29 0858 .01 2254 26.0 277 ST. CROIX, U.S. VIRGIN ISLANDS 50345000 JOLLY HILL GUT AT JOLLY HILL, ST. CROIX, VI LOCATION.--Lat 17°44'00", long 64°51'47", Hydrologic Unit 21020002, on Mahogany Road at Jolly Hill, 1.8 mi (2.9 km) northeast of Frederiksted. DRAINAGE AREA.--2.10 sq mi (5.44 sq km). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1963 to December 1968. Monthly measurements, 1962, 69. October 1982 to September 1983. GAGE.--Water-stage recorder and V-notch concrete control. Altitude of gage is 140 ft (42.7 m) from topographic map. REMARKS.--Records poor. AVERAGE DISCHARGE.--6 years (1964-68, 1983), 0.024 cu ft/s (0.001 cu m/s), 0.16 in/yr (4.1 mm/yr), 17.4 acre-ft/yr (0.02 cu hm/yr). EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 223 cu ft/s (6.315 cu m/s) Dec. 12, 1965, gage height, 3.15 ft (0.96 m); no flow many days each year. EXTREMES FOR CURRENT YEAR.--Peak discharges above base of 25 cu ft/s (0.71 cu m/s) and maximum (*): Date Discharge Time (cu ft/s) (cu m/s) Gage height (ft) (m) July 23 2400 *27 0.76 2.00 0.610 No flow many days. DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1982 TC SEPTEMBER 1983 MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .01 .02 .04 .05 .04 .05 .01 .02 .20 .29 .23 .09 2 .01 .01 .04 .05 .04 .02 .00 .C1 .20 .29 .22 .14 3 .01 .01 .05 .05 .04 .02 .00 .01 .20 .31 .21 .11 4 .01 .01 .04 .06 .04 .02 .00 .01 .20 .31 .21 .09 5 .01 .02 .03 .06 .04 .02 .00 .01 .24 .31 .19 .09 6 .00 .01 .02 .05 .03 .02 .00 .00 .26 .32 .20 .09 7 .00 .00 .02 .05 .03 .02 .00 .00 .27 .31 .18 .08 8 .00 .00 .02 .05 .03 .04 .00 .00 .25 .31 .15 .08 9 .00 .01 .03 .07 .03 .03 .00 .00 .26 .30 .16 .08 10 .00 .00 .03 .06 .04 .02 .00 .01 .26 .28 .15 .09 11 .03 .04 .03 .06 .03 .02 .00 .00 .26 .24 .15 .09 12 .00 .02 .02 .06 .03 .05 .00 .00 .26 .24 .15 .10 13 .00 .01 .02 .05 .03 .07 .00 .C1 .26 .24 .16 .08 14 .30 .01 .02 .05 .03 .05 .00 .02 .26 .24 .15 .08 15 .11 .02 .03 .05 .03 .02 .00 .0.3 .26 .24 .16 .08 16 .06 .03 .04 .05 .03 .02 .00 .C2 .26 .31 .15 .07 17 .05 .03 .03 .05 .02 .01 .00 .10 .28 .30 .14 .07 18 .10 .01 .04 .05 .02 .01 .06 .09 .29 .31 .12 .07 19 .07 .10 .04 .05 .02 .01 .10 .10 .27 .22 .11 .07 20 .05 .04 .03 .05 .02 .01 .08 .10 .28 .14 .14 .10 21 .05 .04 .03 .04 .04 .01 .05 .10 .26 .14 .13 .09 22 .04 .06 .06 .06 .05 .01 .05 .42 .26 .13 .11 .09 23 .05 .07 .04 .05 .05 .02 .05 .27 .26 .31 .10 .09 24 .03 .13 .05 .05 .04 .02 .04 .28 .29 .58 .10 .09 25 .02 .09 .04 .04 .03 .02 .03 .24 .28 .17 .10 .12 26 .02 .07 .04 .04 .02 .01 .03 .22 .26 .18 .10 .11 27 .02 .05 .05 .04 .03 .01 .03 .22 .33 .19 .10 .10 28 .02 .04 .08 .04 .04 .02 .03 .22 .32 .20 .10 .09 29 .02 .04 .08 .04 --- .03 .02 .21 .29 .21 .11 .09 30 .03 .04 .05 .04 .02 .01 .20 .29 .18 .11 .09 31 .03 --- .06 .03 .01 --- .20 --- .19 .10 --- TOTAL 1.15 1.03 MEAN .037 .036 1.20 1.54 .039 .050 . .92 033 .71 .59 .023 .020 3.12 .10 7.86 .26 7.99 .26 4.4; .14 2.71 .090 MAX .30 .13 .08 .07 .05 .07 .10 .42 .33 .58 .23 .14 MIN .00 .00 .02 .03 .02 .01 .00 .00 .20 .13 .10 .07 CFSM .02 .02 .02 .02 .02 .01 .01 .05 .12 .12 .07 .04 IN. .02 .02 .02 .03 .02 .01 .01 .C6 .14 .14 .08 .05 AC-FT 2.3 2.1 2.4 3.1 1.8 1.4 1.2 6.2 16 16 8.9 5.4 WTR YR 1983 TOTAL 33.36 MEAN .091 MAX .58 MIN .00 CFSM .04 IN .59 AC-FT 66 WATER-QUALITY RECORDS PERIOD OF RECORD.--MARCH TO SEPTEMBER 1983 WATER-QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 STREAMFLOW, SPECIFIC CON- TEMPERA- STREAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DUCTANCE TURE (CFS) (UMi0S) (DEG C) (CFS) (UMHOS) (DEG C) MAR, 24 1020 .02 1132 24.0 SEP, 27 1103 .11 1067 26.5 JUL, 19 1044 .16 1142 27.0 Ground-Water Records for U.S. Virgin Islands 280 O 1 2 3 MILES O 1 2 3 4 KILOMETERS O 1 2 3 MILES I O 1 2 3 4 KILOMETERS O 1 2 3 MILES 1 I ' 2 3 4 KILOMETERS O 1 Figure 28.--Ground-water stations in the U.S. Virgin Islands. 281 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.--Altitude of land-surface datum is about 20 ft (6.10 m) above mean sea level. 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.-- Water level: March 1982 to current year. Chemical analyses: June 20, 1983 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 YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 15, 1982 15.64 Sept. 8, 1982 a56.04 Feb. 24, 1983 a56.45 July 19, 1983 a55.94 May 24 18.68 Oct. 25 a56.55 Mar. 24 16.31 Aug. 23 17.83 June 30 55.90 Dec. 8, a56.59 May 18 17.56 Sept. 27 a56.50 July 22 a56.34 Jan. 21, 1983 17.36 June 20 a58.57 174225064472000. Local number, 2. LOCATION.--Lat 17°42'25", 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: Altitude of land-surface datum is about 20 ft (6.10 m) above mean sea level. Measuring point: Top of 0.5 in (0.01 m) hole at concrete base wall, 3.00 ft (0.91 m) above land-surface datum. REMARKS.--Observation recording well. Nearby pumping well. PERIOD OF RECORD.--June 1983 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 21.90 ft (6.68 m) below land-surface datum, Sept. 6, 1983; lowest water level measured, 23.18 ft (7.07 m) below land-surface datum, July 19, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 22.73 22.29 22.11 2 22.82 22.30 21.99 3 22.86 22.28 22.08 4 22.89 22.17 22.03 5 22.85 22.22 22.00 6 22.90 22.24 21.91 7 22.87 22.23 21.93 8 22.98 22.21 21.92 9 22.90 22.15 21.95 10 22.92 22.19 22.00 11 22.94 22.21 21.95 12 23.01 22.19 21.98 13 22.76 22.19 21.98 14 23.01 22.15 22.04 15 22.97 22.15 22.07 16 23.07 22.20 22.02 17 23.10 22.16 22.03 18 23.03 22.15 22.03 19 23.17 22.15 22.12 20 22.95 22.15 22.09 21 22.76 22.10 22.38 22 --- 22.70 22.10 22.49 23 22.53 22.67 22.10 22.55 24 22.54 22.61 22.11 22.48 25 22.60 22.53 22.08 22.48 26 22.62 22.49 21.99 22.49 27 22.66 22.44 22.03 22.51 28 22.73 22.39 22.07 22.52 29 22.74 22.39 22.03 22.54 30 22.77 22.37 22.08 22.63 31 --- 22.33 22.04 LOW 23.17 22.30 22.63 NIGH 22.33 21.99 21.91 a Pumping. 282 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174243064475100. Local number, 3. LOCATION.--Lat 17°42'43", Long 64°47'51". 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.--Altitude of land-surface datum is about 40 ft (12.2 m) above mean sea level. Measuring point: Upper edge of hole at 8 in (0.20 m) casing, 4.20 ft (1.28 m) above land-surface datum. REMARKS.--Observation well. Automatic Digital Recorder (ADR) installed on June 22, 1983. PERIOD OF RECORD.--March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 14.76 ft (4.50 m) below land-surface datum, March 25, 1982; lowest water level measured, 24.98 ft (7.62 m) below land-surface datum, Sept. 30, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 25, 1982 14.76 Sept. 8, 1982 19.32 Jan. 21, 1983 22.36 May 18, 1983 20.37 May 23 15.95 Oct. 25 20.45 Feb. 24 22.75 June 20 22.43 June 30 17.16 Dec. 8 21.61 Mar. 24 23.05 June 22 22.47 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 23.07 23.85 24.44 2 3 4 23.12 23.17 23.22 23.87 23.89 23.91 24.46 24.48 24.49 5 23.27 23.93 24.51 6 7 23.32 23.37 23.95 23.97 24.52 24.53 8 23.41 23.99 24.55 9 23.45 24.01 24.57 10 23.49 24.04 24.57 11 12 23.53 23.56 24.05 24.07 24.59 24.61 13 14 15 23.60 23.64 23.67 24.09 24.11 24.13 24.62 24.64 24.66 16 17 18 19 20 23.71 23.74 23.77 23.80 23.83 24.16 24.17 24.19 24.21 24.23 24.68 24.69 24.71 24.73 24.75 21 22 23 24 25 22.64 22.71 23.85 23.79 23.77 23.79 23.81 24.25 24.27 24.27 24.29 24.31 24.77 24.79 24.81 24.83 24.85 26 27 28 29 30 31 22.78 22.84 22.89 22.95 23.01 --- 23.83 23.76 23.69 23.72 23.77 23.81 24.33 24.35 24.37 24.39 24.41 24.42 24.87 24.90 24.92 24.95 24.97 --- LOW HIGH 23.85 23.07 24.42 23.85 24.97 24.44 174245064475800. Local number, 4. LOCATION.--Lat 17°42'45", 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 (0-31.7 m), perforated 64-104 ft (19.5-31.7 m). Depth 104 ft (31.7). DATUM.--Altitude of land-surface datum is about 40 ft (12.2 m) above mean sea level. 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. Lowest water level affected by pumping. PERIOD OF RECORD.-- Water level: January 1983 to current year. Chemical analyses: June 20, 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, a54.18 ft (16.5 m) below land-surface datum, September 27, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Jan. 21, 1983 23.48 Mar. 24, 1983 24.71 June 20, 1983 25.26 Aug. 23, 1983 26.03 Feb. 24 23.83 May 18 23.09 July 19 a51.32 Sept. 27 a54.18 a Pumping. 283 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174336064523200. Local number, 5. LOCATION.--Lat 17°43'36", long 64°52'32". Owner: Virgin Islands Government. Name: Mahogany Road 3. AQIFER.--Alluvium of Quaternary age and volcanic rocks of Cretaceous age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 6 in (0.15 m), cased 6 in (0.15 m) 0-104 ft (0-31.7 m), perforated 64-104 ft (19.5-31.7). Depth 104 ft (31.7 m). DATUM.--Altitude of land-surface datum is 70 ft (21.3 m) above mean sea level. Measuring point: lower edge of 2 in. (0.05 m) pipe at pump base, 3.70 ft (1.13 m) above land-surface datum. Prior to December 1969, top of instrument platform, 2.57 ft (0.78 m) above land-surface datum. REMARKS.--Observation well. Affected by nearby pumpage. PERIOD OF RECORD.--May 1964 to December 1969, discontinued. March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 26.24 ft (8.00 m) below land-surface datum, Dec. 16, 1969; lowest water level measured, 74.31 ft (22.6 m) below land-surface datum, Mar. 29, 1965. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 25, 1982 51.40 Sept. 8, 1982 64.48 Feb. 24, 1983 64.03 July 19, 1983 64.89 May 24 57.43 Oct. 25 66.28 Mar. 24 64.24 Aug. 23 60.56 June 30 60.47 Dec. 8 68.62 May 18 66.35 Sept. 27 57.97 July 22 61.24 Jan. 21, 1983 65.14 June 20 67.15 174308064484400. Local number, 6. LOCATION.--Lat 17°43'03", long 64°48'44". 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). DATUM.--Altitude of land-surface datum is about 80 ft (24.4 m) above mean sea level. 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.--Observation well. Automatic Digital Recorder (ADR) installed on June 20, 1983. PERIOD OF RECORD.--August 1973 to March 1974, discontinued. March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 24.90 ft (7.59 m) below land-surface datum, Mar. 25, 1982; lowest water level measured, 35.12 ft (10.7 m) below land-surface datum, Jul. 21, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 25, 1982 24.90 July 22, 1982 28.59 Dec. 8, 1982 34.10 Mar. 24, 1983 32.70 May 24 26.38 Sept. 8 30.68 Jan. 21, 1983 32.76 May 18 31.63 June 30 28.06 Oct. 25 32.77 Feb. 24 31.10 June 20 32.63 WATER LEVEL. IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 34.30 33.90 34.66 2 34.35 33.85 34.63 3 34.42 33.82 34.61 4 34.44 33.80 34.57 5 34.49 33.78 34.54 6 34.55 33.76 34.50 7 34.60 33.75 34.46 8 34.63 33.74 31.43 9 34.68 33.74 34.40 10 34.72 33.75 34.38 11 34.76 33.75 34.36 12 34.76 33.75 34.38 13 34.76 33.75 34.34 14 34.78 33.75 34.32 15 34.86 33.75 34.32 16 34.89 33.75 34.30 17 34.94 33.76 34.28 18 34.97 33.76 34.26 19 34.97 33.76 34.27 20 35.04 33.77 34.24 21 --- 35.01 33.78 22 33.62 34.70 33.78 23 33.72 34.50 33.79 24 33.80 34.25 34.78 25 33.88 34.27 34.77 26 33.99 34.20 34.74 27 34.05 34.12 34.73 28 34.13 34.08 34.71 34.47 29 34.17 31.32 34.70 34.44 30 34.24 33.93 34.67 34.43 31 --- 33.93 34.65 LOW 35.04 34.78 HIGH 31.32 33.74 284 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174525064460600. Local number, 7. LOCATION.--Lat 17°45'25", long 64°46'06". 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 (25.9 m). DATUM.--Altitude of land-surface datum is about 40 ft (12.2 m) above mean sea level. 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 level affected by pumpage. PERIOD OF RECORD.--March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 26.45 ft (8.06 m) below land-surface datum, Aug. 23, 1983; lowest water level measured, a41.75 ft (12.7 m) below land-surface datum, Feb. 24, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 25, 1982 a27.36 Sept. 8, 1982 a36.23 Feb. 24, 1983 a41.75 July 19, 1983 a38.00 May 24 a28.27 Oct. 25 a38.46 Mar. 24 31.30 Aug. 23 26.45 June 30 July 22 a30.82 a34.92 Dec. Jan. 8 21, 1983 a39.28 30.33 May 18 June 20 28.04 a35.10 Sept. 27 a36.84 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. Depth 82 ft (25.0 m). DATUM.--Altitude of land-surface datum is about 40 ft (12.2 m) above mean sea level. Measuring point: Top of 6 in (0.15 m) casing, 2.20 ft (0.67 m) above land-surface datum. REMARKS.--Observation well. Affected by pumpage. PERIOD OF RECORD.--March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 19.97 ft (6.09 m) below land-surface datum, Mar. 25, 1982; lowest water level measured, a28.39 ft (8.66 m) below land-surface datum, Dec. 8, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 25, 1982 a19.97 Sept. 8, 1982 a25.70 Feb. 24, 1983 27.92 July 19, 1983 26.25 May 24 22.43 Oct. 25 a26.88 Mar. 24 27.18 Aug. 23 a26.22 June 30 a23.40 Dec. 8 a28.39 May 18 25.82 Sept. 27 25.63 July 22 23.63 Jan. 21, 1983 a28.34 June 21 a24.70 a Pumping. 285 GROUND-WATER LEVELS ST. CROIX, U.S. VIRGIN ISLANDS 174532064460300. Local number, 9. LOCATION.--Lat 17°45'32", long 64°46'03". 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.--Altitude of land-surface datum is 35 ft (10.7 m) above mean sea level. 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. PERIOD OF RECORD: Water levels: June 1962 to October 1968, discontinued. March 1982 to current year. Chemical analysis: October 1964 to October 1967, discontinued. 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 YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 25, 1982 a12.83 Sept. 8, 1982 a14.69 Feb. 24, 1983 a34.62 July 19, 1983 a31.17 May 24 a12.84 Oct. 25 al3.60 Mar. 24 12.03 Aug. 23 10.24 June 30 a13.58 Dec. 8 11.53 May 18 10.66 Sept. 27 a42.07 July 22 a13.20 Jan. 21, 1983 9.35 June 20 a29.30 174329064454700. Local number, 10. LOCATION.--Lat 17°43'29", long 64°45'47". 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 (0-39.6 m), perforated 71-130 ft (21.6-39.6 m). Depth 130 ft (39.6 m). DATUM.--Altitude of land-surface datum is 75 ft (22.9 m) above mean sea level. Measuring point: Hole on top of pump base, 2.00 ft (0.61 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD: Water level: March 1982 to current year. Chemical analyses: June 22, 1983 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 61.86 ft (18.9 m) below land-surface datum, Mar. 26, 1982; lowest water level measured, a75.52 ft (23.0 m) below land-surface datum, Sept. 8, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 26, 1982 61.86 Sept. 8, 1982 a75.52 Feb. 24, 1983 a70.55 July 19, 1983 a70.48 May 25 a69.50 Oct. 25 a70.05 Mar. 24 a69.83 Aug. 23 64.29 June 30 a69.48 Dec. 8, a70.25 May 18 63.22 Sept. 27 a69.58 July 22 a69.21 Jan. 21, 1983 65.41 June 22 a70.38 a Pumping. 286 GROUND-WATER LEVELS ST. THOMAS, U.S. VIRGIN ISLANDS 182050064580400. Local number, 1. LOCATION.--Lat 18°20'50", long 64°58'04". 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), openhole 25-80 ft (7.62-24.4 m). Depth 80 ft (24.4 m). DATUM.--Altitude of land-surface datum is 80 ft (24.4 m) above mean sea level. 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.--Public water supply and observation well. PERIOD OF RECORD: Water levels: October 1963 to August 1969, discontinued. March 1982 to current year. Chemical analyses: December 1963, discontinued. June 30, 1983 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 5.29 ft (1.61 m) below land-surface datum, May 6, 1983; lowest water level measured, a44.49 ft (13.6 m) below land-surface datum, Mar. 22, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 23, 1982 May 28 June 23 July 21 27.37 30.26 30.88 32.19 Sept. 10, 1982 Oct. 27 Dec. 10 Jan. 19, 1983 33.84 34.53 33.35 29.52 Feb. 22, 1983 Mar. 22 May 6 19 a37.89 a44.49 5.29 7.08 June 30, 1983 July 20 Aug. 25 Sept. 27 7.63 8.65 al5.77 23.15 182138064543100. Local number, 2. LOCATION.--Lat 18°21'38", long 64°54'31". Owner: Mahogany Run Resort. Name: Mahogany 15. 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 (44.2 m). DATUM.--Altitude of land-surface datum is 120 ft (36.6 m) above mean sea level. Measuring point: Top of 6 in (0.15 m) casing, 1.20 ft (0.36 m) below land-surface datum. REMARKS.--Potable water supply. Observation well. Water level affected by nearby pumping well. PERIOD OF RECORD.--March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 18.58 ft (5.66 m) below land-surface datum, July 20, 1983; lowest water level measured, 48.38 ft (14.8 m) below land-surface datum, Mar. 22, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 22, 1982 30.58 Sept. 10, 1982 43.35 Feb. 22, 1983 46.20 July 20, 1983 18.58 May 28 a39.58 Oct. 27 43.73 Mar. 22 48.38 Aug. 25 19.61 June 23 38.04 Dec. 16 40.10 May 19 29.17 Sept. 28 24.70 July 21 40.97 Jan. 19, 1983 42.14 July 1 21.76 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 (44.2 m) DATUM.--Altitude of land-surface datum is 130 ft (39.6 m) above mean sea level. Measuring point: Top of 6 in (0.15 m) casing, 1.30 ft (0.40 m) below land-surface datum. REMARKS.--Potable water supply. Water level affected by nearby pumping. PERIOD OF RECORD.--March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 24.96 ft (7.61 m) below land-surface datum, Aug. 25, 1983; lowest water level measured, a68.20 ft (20.8 m) below land-surface datum, July 21, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 22, 1982 61.10 Sept. 10, 1982 48.34 Feb. 22, 1983 a54.37 July 20, 1983 25.28 May 28 41.44 Oct. 27 47.47 Mar. 22 50.68 Aug. 25 24.96 June 23 a67.50 Dec. 16 45.50 May 19 34.39 Sept. 28 30.07 July 21 a68.20 Jan. 19, 1983 47.09 July 1 25.53 a Pumping. 287 GROUND-WATER LEVELS ST. THOMAS, U.S. VIRGIN ISLANDS 182136064541900. Local number, 4. LOCATION.--lat 18°21'36", long 64°54'19". 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 (44.2 m). DATUM.--Altitude of land-surface datum is 140 ft (42.7 m) above mean sea level. Measuring point: Top of 6 in (0.15 m) casing at land-surface datum. REMARKS.--Potable water supply. Water level affected by nearby pumping. PERIOD OF RECORD.--March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 25.60 ft (7.80 m) below land-surface datum, July 20, 1983; lowest water level measured, a60.40 ft (18.4 m) below land-surface datum, Sept. 10, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 22,1982 a53.77 Sept. 10, 1982 a60.40 Feb. 22, 1983 44.84 July 20, 1983 25.60 May 28 39.55 Oct. 27 42.44 Mar. 22 a52.64 Aug. 25 26.01 June 23 41.46 Dec. 16 46.60 May 19 33.61 Sept. 28 31.47 July 21 42.88 Jan. 19, 1983 46.36 July 1 26.98 182029064535200. Local number, 5. LOCATION.--Lat 18°20'29", long 64°53'52". 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), openhole 20-400 ft (6.10-122 m). Dept 400 ft (122 m). DATUM.--Altitude of land-surface datum is about 235 ft (71.6 m) above mean sea level. 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: Water levels: March 1982 to current year. Chemical analyses: July 1, 1983 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 71.44 ft (21.8 m) below land-surface datum, July 1, 1983; lowest water level measured, 88.37 ft (26.9 m) below land-surface datum, July 21, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 23,1982 87.03 Sept. 10, 1982 86.20 Feb. 22, 1983 86.82 July 20, 1983 75.50 May 28 84.97 Oct. 27 83.95 Mar. 22 85.99 Aug. 25 75.79 June 23 85.72 Dec. 10 83.10 May 19 73.89 Sept. 28 78.05 July 21 88.37 Jan. 19, 1983 84.15 July 1 71.44 a Pumping. 288 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.--Altitude of land-surface datum is 60 ft (18.3 m) above mean sea level. 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.--Observation well. Automatic Digital Recorder (ADR) was installed on June 27, 1983. PERIOD OF RECORD.--March 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 10.56 ft (3.22 m) below land-surface datum, July 9, 1983; lowest water level measured, 35.38 ft (10.8 m) below land-surface datum, July 21, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 22, 1982 32.01 July 21, 1982 35.38 Dec. 10, 1982 27.64 Mar. 22, 1983 27.42 May 28 31.12 Sept. 10 32.18 Jan. 19, 1983 23.50 May 19 13.40 June 23 34.21 Oct. 26 28.73 Feb. 22 29.47 WATER LEVEL. IN FEET BELOW LAND-SURFACE DATUM• WATER YEAR OCTOBER 1932 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 11.91 14.49 16.74 2 12.05 14.54 16.86 3 12.16 14.21 16.97 4 12.26 14.14 17.08 5 12.35 14.34 17.19 6 12.28 14.55 17.31 7 11.70 14.76 17.45 8 10.96 14.97 17.57 9 10.62 15.18 17.77 10 10.71 15.40 17.90 11 11.03 15.60 18.00 12 11.29 15.78 18.10 13 11.52 15.93 18.22 14 11.73 16.05 18.37 15 11.95 16.18 18.56 16 12.17 16.31 19.21 17 12.37 16.43 19.75 18 12.58 16.53 20.21 19 12.76 16.62 20.55 20 12.95 16.70 20.84 21 13.14 16.74 21.04 22 13.34 16.22 21.23 23 13.55 15.87 21.37 24 13.69 15.95 21.47 25 13.46 16.09 21.54 26 13.57 16.26 21.62 27 13.74 16.46 21.70 28 11.66 13.91 16.62 21.82 29 11.67 14.10 16.64 21.89 30 11.77 14.24 16.62 21.98 31 --- 14.37 16.67 LOW 14.37 16.74 21.98 HIGH 10.62 14.14 16.74 289 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182010064472600. Local number, 1. LOCATION.--Lat 18°20'10", long 64°47'26". Owner: U.S. Government, National Park Services. Name: NPS-2 (Cruz Bay). AQUIFER: Volcanic rocks of Cretaceous Age. WELL CHARACTERISTICS.--Drilled unused water-table well, diameter 6 in (0.15 m), 4 in (0.10 m), cased 0-20 ft (0-6.10 m), open hole 20-99 ft (6.10-30.2 m). Depth 99 ft (30.2 m). DATUM: Altitude of land-surface datum is 60 ft (18.3 m) above mean sea level. Measuring point: Top of 4 in (0.10 m) casing, 4.10 ft (1.25 m) above old land-surface datum after 1.4 ft (0.43 m) land fill and 2.7 ft (0.82 m) casing extension occurred. Prior to June 29, 1983, top of 4 in (0.10 m) casing, 1.4 ft (0.43 m) above land-surface datum. REMARKS.--Observation well. Lowest water level affected by pumping nearby well. PERIOD OF RECORD: Water levels: May 1964, discontinued. June 30, 1983 to current year. Chemical analyses: May 1964, discontinued. June 30, 1983 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 5.39 ft (1.64 m) below land-surface datum, Aug. 24, 1983; 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 YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 24, 1982 26.28 Oct. 26, 1982 13.23 Mar. 23, 1983 32.10 July 21, 1983 21.00 May 25 17.36 Dec. 9 16.80 June 29 20.56 Aug. 24 5.39 June 21 22.82 Jan. 20, 1983 25.04 June 30 20.20 Sept. 29 27.59 Sept. 9 28.55 Feb. 23 29.87 182109064460300. Local number, 2. LOCATION.--Lat 18°21'09", long 64°46'03". 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.--Altitude of land-surface datum is 60 ft (18.3 m) above mean sea level. 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: Water levels: August 1964 to December 1969, discontinued. March 1982 to current year. Chemical analyses: July 1964 to June 1969, discontinued. June 30, 1983 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 16.76 ft (5.11 m) below land-surface datum, June 3, 1969; lowest water level measured, a57.29 ft (17.5 m) below land-surface datum, Nov. 27, 1968. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 24, 1982 15.13 Sept. 9, 1982 25.02 Feb. 23, 1983 31.57 July 21, 1983 26.12 May 25 22.37 Oct. 26 26.34 Mar. 23 35.46 Aug. 24 28.84 June 21 a38.90 Dec. 9 a45.67 May 19 a40.09 Sept. 29 a40.97 July 20 22.30 Jan. 20, 1983 a29.23 June 30 23.02 a Pumping. 290 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182116064451000. Local number, 3. LOCATION.--Lat 18°21'16", long 64°45'10". 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 (0-15.6 m), open hole 51-70 ft (15.6-21.3 m). Depth 70 ft (21.3 m). DATUM.--Altitude of land-surface datum is 60 ft (18.3 m) above mean sea level. Measuring point: Hole on 6 in (0.15 m) casing, 2.0 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. Automatic Digital Recorder (ADR) installed on June 29, 1983. PERIOD OF RECORD: Water levels: August 1964 to December 1969, discontinued. March 1982 to current year. Chemical analyses: August 1964 to June 1969, discontinued. June 29, 1983 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 41.12 ft (12.5 m) below land-surface datum, Aug. 15, 1969; lowest water level measured, 63.15 ft (19.2 m) below land-surface datum, July 1, 1968. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 24, 1982 52.75 July 20, 1982 56.60 Dec. 9, 1982 56.34 Mar. 23, 1983 58.00 May 25 55.48 Sept. 9 56.42 Jan. 20, 1983 56.90 Apr. 27 57.28 June 21 54.64 Oct. 26 59.10 Feb. 23 57.00 May 19 57.16 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM• WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 56.44 56.76 56.02 2 56.47 56.76 56.05 3 56.51 56.76 56.08 4 56.54 56.76 56.12 5 56.57 56.77 56.15 6 56.57 56.80 56.16 7 56.54 56.82 56.17 8 56.52 56.83 56.17 9 56.52 56.85 56.18 10 56.52 56.85 56.21 11 56.52 56.85 56.25 12 56.53 56.87 56.33 13 56.55 56.86 56.41 14 56.59 56.82 56.47 15 56.61 56.79 56.52 16 56.64 56.78 56.54 17 56.64 56.78 56.56 18 56.64 56.77 56.58 19 56.64 56.76 56.58 20 56.64 56.75 56.58 21 56.67 56.74 56.58 22 56.69 56.62 56.59 23 56.72 56.48 56.61 24 56.76 56.34 56.63 25 56.77 56.22 56.63 26 56.78 56.14 56.62 27 56.77 56.07 56.58 28 56.75 56.05 56.54 29 56.75 56.04 56.49 30 56.40 56.75 56.03 56.48 31 56.76 56.02 LOW 56.78 56.87 56.63 HIGH 56.44 56.02 56.02 181951064422100. Local number, 4. LOCATION.--Lat 18°19'51", long 64°42'21". Owner: U.S. Government, Virgin Islands Government. Name: USGS-15 (Calabash Boom). AQUIFER.--Volcanic rocks of Cretaceous age. WELL CHARACTERISTICS.--Drilled unused water-table well diameter 6 in (0.15 m), cased 0-61 ft (0-18.6 m), slotted 40-61 (12.2-18.6 m). Depth 62 ft (18.9 m). DATUM: Altitude of land-surface datum is 50 ft (15.2 m) above mean sea level. Measuring point: Top of 6 in (0.15 m) casing, 1.10 ft (0.34 m) above land-surface datum. Previous to March 1982, top of 6 in. (0.15 m) casing, 1.40 ft (0.43 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD: Water levels: September 1964 to December 1967, discontinued. March 1982 to current year. Chemical analyses: September 22, 1964, discontinued. June 30, 1983 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured 39.55 ft (12.1 m) below land-surface datum, May 25, 1982; lowest water level measured, 44.55 ft (13.6 m) below land-surface datum, Mar. 22, 1965. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 24, 1982 41.37 June 21, 1982 40.51 Sept. 9, 1982 42.00 Dec. 9, 1982 42.26 May 25 39.55 July 20 41.18 Oct. 26 42.20 June 30, 1983 40.79 GROUND-WATER LEVELS 291 ST. JOHN, U.S. VIRGIN ISLANDS 182042064454500. Local number, 5. LOCATION.--Lat 18°20'42", long 64°45'45". Owner: Virgin Islands Government. Name: DPW-6. 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.--Altitude of land-surface datum is about 640 ft (195 m) above mean sea level. 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.--Observation well. Automatic Digital Recorder (ADR) installed on June 28, 1983. PERIOD OF RECORD.--September 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 11.34 ft (3.46 m) below land-surface datum, Apr. 27, 1983; lowest water level measured, 17.72 ft (5.40 m) below land-surface datum, Mar. 23, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Sept. 9, 1982 12.49 Dec. 9, 1982 12.49 Feb. 23, 1983 16.62 Apr. 27, 1983 11.34 Oct. 26 14.25 Jan. 20, 1983 14.66 Mar. 23 17.72 May 29 12.29 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT DAY OCT NOV DEC JAN FEB MAR APR 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 LOW HIGH 182044064454600. Local number, 6. LOCATION.--Lat 18°20'44", long 64°45'46". Owner: Virgin Islands Government. Name: DPW-5. AQUIFER.--Louisenhoj Formation. 1200 MAY JUN JUL AUG SEP 15.52 17.02 13.89 15.61 17.03 14.06 15.67 17.02 14.22 15.73 17.02 14.36 15.76 17.02 14.47 15.79 17.06 14.61 15.79 17.09 14.77 15.81 17.14 14.90 15.86 17.19 15.00 15.92 17.22 15.11 15.99 17.27 15.25 16.05 17.28 15.35 16.13 17.28 15.45 16.19 17.28 15.57 16.24 17.27 15.81 16.31 17.27 15.94 16.35 17.26 16.02 16.40 17.15 16.09 16.43 17.07 16.14 16.47 17.04 16.16 16.64 15.77 16.16 16.64 15.37 16.16 16.63 15.22 16.16 16.67 15.05 16.16 16.70 14.90 16.16 16.73 14.77 16.16 16.76 14.67 16.16 16.84 13.97 16.16 15.42 16.88 13.12 16.95 15.49 16.91 13.32 16.96 --- 16.95 13.64 16.95 17.28 16.96 15.52 13.12 13.89 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.--Altitude of land-surface datum is about 640 ft (195 m) above mean sea level. Measuring point: Top of 6 in (0.15 m) casing, 1.40 ft (0.43 m) above land-surface datum. REMARKS.--Observation well. PERIOD OF RECORD: Water levels: September 1982 to current year. Chemical analyses: June 30, 1983 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 36.71 ft (11.2 m) below land-surface datum, Sept. 9, 1983; lowest water level measured, a104.96 ft (32.0 m) below land-surface datum, May 19, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Date Water level Date Water level Date Water level Date Water level Sept. Oct. Dec. 9, 1982 26 9 36.71 a83.85 a102.14 Jan. 20, 1983 Feb. 23 Mar. 23 48.91 47.60 53.76 May June 30 July 21 19, 1983 a104.96 44.17 57.58 Aug. 24, 198 Sept. 29 3 a71.90 46.89 a Pumping. 292 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182044064454800. Local number, 7. LOCATION.--Lat 18°20'44, long 64°45'48". 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: Altitude of land-surface datum is about 640 ft (195 m) above mean sea level. 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, 25.36 ft (7.73 m) below land-surface datum, Sept. 9, 1982; lowest water level measured, 49.10 ft (15.0 m) below land-surface datum, Oct. 26, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Date Water level Date Water level Date Water level Date Water level Sept. Oct. Dec. 9, 1982 26 9 25.36 49.10 33.42 Jan. 20, 1983 Feb. 23 Mar. 23 37.49 37.24 48.05 May 19, 1983 June 30 July 21 47.75 34.34 39.82 Aug. Sept. 29 24, 1983 46.45 36.54 182044064454900. Local number, 8. LOCATION.--Lat 18°20'44", 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.--Altitude of land-surface datum is about 640 ft (195 m) above mean sea level. 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, 20.93 ft (6.38 m) below land-surface datum, Sept. 9, 1982; lowest water level measured, a69.08 ft (21.1 m) below land-surface datum, Dec. 9, 1982. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Sept. 9, 1982 20.93 Jan. 20, 1983 32.55 May 19, 1983 a68.99 Aug. 24, 1983 68.10 Oct. 26 a66.20 Feb. 23 32.46 June 30 29.87 Sept. 29 31.87 Dec. 9 a69.08 Mar. 23 54.48 July 21 34.39 182044064455000. Local number, 9. LOCATION.--Lat 18°20'44", long 64°45'50". 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.--Altitude of land-surface datum is 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. PERIOD OF RECORD.--September 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 32.84 ft (10.0 m) below land-surface datum, Sept. 9, 1982; lowest water level measured, 52.44 ft (16.0 m) below land-surface datum, May 19, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Sept. 9, 1982 32.84 Jan. 20, 1983 41.54 May 19, 1983 52.44 Aug. 24, 1983 51.62 Oct. 26 51.05 Feb. 23 41.43 June 30 38.21 Sept. 29 40.19 Dec. 9 51.43 Mar. 23 45.79 July 21 40.85 a Pumping. 293 GROUND-WATER LEVELS ST. JOHN, U.S. VIRGIN ISLANDS 182044064455200. Local number, 10. LOCATION.--Lat 18°20'44", long 64°45'52". 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.--Altitude of land-surface datum is 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. PERIOD OF RECORD.--September 1982 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 32.03 ft (9.76 m) below land-surface datum, Sept. 9, 1983; lowest water level measured, a37.60 ft (11.5 m) below land-surface datum, Dec. 9, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Date Water level Date Water level Date Water level Date Water level Sept. 9, 1982 Oct. 26 Dec. 9 32.03 36.05 a37.60 Jan. 20, 1983 Feb. 23 Mar. 23 36.79 37.21 37.44 May 19, 1983 June 30 July 21 34.23 33.31 35.89 Aug. 24, 1983 Sept. 29 35.88 36.58 181956064464500. Local number, 11. LOCATION.--Lat 18°19'56", long 64°46'45". Owner: Virgin Islands Government. Name: Guinea Gut Well. AQUIFER.--Louisenhoj Formation. 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.--Altitude of land-surface datum is about 280 ft (85.4 m) above mean sea level. 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.--Observation well. Automatic Digital Recorder (ADR) installed on June 28, 1983. PERIOD OF RECORD: Water levels: March 1982 to current year. Chemical analyses: June 30, 1983 to current year. EXTREMES FOR PERIOD OF RECORD.--Highest water level measured, 3.34 ft (1.02 m) below land-surface datum, May 25, 1982; lowest water level measured, 13.55 ft (4.13 m) below land-surface datum, Mar. 23, 1983. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEARS OCTOBER 1981 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS Water Water Water Water Date level Date level Date level Date level Mar. 24, 1982 3.60 July 20, 1982 6.42 Dec. 9, 1982 5.20 Mar. 23, 1983 13.55 May 25 3.34 Sept. 9 9.18 Jan. 20, 1983 6.93 Apr. 27 5.57, June 21 5.04 Oct. 26 8.60 Feb. 23 10.39 May 19 4.77 WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 INSTANTANEOUS OBSERVATIONS AT 1200 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 7.70 8.58 4.58 2 7.79 8.23 4.68 3 7.89 8.12 4.75 4 7.97 8.18 4.82 5 7.98 8.29 4.91 6 7 8 9 10 7.58 7.01 6.80 6.90 7.00 8.37 8.45 8.57 8.68 8.73 4.99 5.11 5.23 5.39 5.59 11 12 13 14 15 7.12 7.26 7.42 7.56 7.69 8.80 8.87 8.35 8.35 8.42 5.78 5.99 6.22 6.47 6.63 16 17 18 19 20 7.81 7.92 8.01 8.16 8.28 8.48 8.53 7.91 7.92 8.04 6.68 6.82 6.96 7.12 7.31 21 22 23 24 25 8.40 8.52 8.65 8.52 8.40 6.23 5.32 5.34 5.50 5.68 7.45 7.60 7.73 7.81 7.85 26 27 28 29 30 31 --- 7.57 7.54 7.61 --- 8.41 8.45 8.56 8.64 8.57 8.65 5.83 5.99 4.35 4.19 4.33 4.45 7.77 7.82 7.92 8.07 8.20 --- LOW HIGH 8.65 6.80 8.87 4.19 8.20 4.58 a Pumping. 294 QUALITY Of GROUND WATER WATER QUALITY DATA, WATER YEAR OCTOBER 1982 TO SEPTEMBER 1983 STATION NUMBER 174225064471900 174245064475300 174329064454700 TOTAL DEPTH OF WELL (FT) 104 130 SPECIFIC CONDUCT- PH DATE ANCE (STAND- OF (MICRO- ARD SAMPLE MHOS) UNITS) SAINT CROIX, U.S. VIRGIN ISLANDS 06-20-83 4750 7.4 06-20-83 2300 7.2 06-22-83 2900 8.0 TEMPER- ATURE (DEG C) 27.5 27.0 27.0 ALKA- LINITY, TOTAL AS CaCO3 (MG/L) 517 610 587 CHLO- RIDE, TOTAL (MG/L) 1100 275 420 182050064580400 182029064535200 80 400 SAINT 06-30-83 07-01-83 THOMAS, U.S. 900 1800 VIRGIN ISLANDS 7.2 7.6 30.0 28.0 212 576 94 145 182010064472600 99 SAINT JOHN, U.S. VIRGIN ISLANDS 06-30-83 800 6.7 28.0 276 36 182109064460300 182116064451000 181951064422100 60 70 62 06-30-83 06-29-83 06-30-83 1620 1800 750 7.0 7.6 7.1 26.5 29.0 28.5 464 456 167 220 265 84 182044064454600 145 06-30-83 1650 7.2 28.0 512 185 181956064464500 85 06-30-83 2400 7.7 26.0 569 390 295 PUBLICATIONS ON TECHNIQUES OF MATER-RESOURCES INVESTIGATIONS Thirty-seven manuals by the U.S. Geological Survey have been published to date in the series on techniques describing procedures for planning and executing specialized work in water-resources investigations. The material is grouped under m tjor subject headings called books and is further divided into sections and chapters. For example, Section A of Book 3 (Applications of Hydraulics) is on surface water. The chapter, the unit of publication, is limited to a narrow field of subject matter. This form at permits flexibility in revision and publication as the need arises. The reports listed below are for sale by the U.S. Geological Survey, Branch of Distribution, 604 South Pickett St., Alexandria, VA 22304 (authorized agent of the Superintendent of Documents, Government Printing Office). NOTE: When ordering 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 01. 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 D2. 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-resources 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 A5. 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 A7. 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-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-B1. Aquifer-test design, observation, and data analysis, by R. W. Stallman: USGS--TWRI Book 3, Chapter Bl. 1971. 26 pages. 3-B2. Introduction to ground-water hydraulics, a programed text for 84r-instruction, by G. D. Bennett: USGS--TWRI Book 3, Chapter B2. 1976. 172 pages. 3-B3. Type curves for selected problems of flow to wells in confined aquifers, by J. E. Reed: USGS--TWRI Book 3, Chapter B3. 1980. 106 pages. 3-Cl. Fluvial sediment concepts, by H. P. Guy: USGS--TWRI Book 3, Chapter Cl. 1970. 55 pages. 3-C2. Field methods for measurement of fluvial sediment, by H. P. Guy and V. W. Norman: USGS--TWRI Book 3, Chapter C2. 1970. 59 pages. 3-C3. Computation of fluvial-sediment discharge, by George Porterfield: USGS--TWRI Book 3, Chapter C3. 1972. 66 pages. 4-Al. Some statistical tools in hydrology, by H. C. Riggs: USGS--TWRI Book 4, Chapter Al. 1968. 39 pages. 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-B2. Storage analyses for water supply, by H. C. Riggs and C. H. Hardison: USGS--TWRI Book 4, Chapter B2. 1973. 20 pages. 4-B3. Regional analyses of streamflow characteristics, by H. C. Riggs: USGS--TWRI Book 4, Chapter B3. 1973. 15 pages. 4-01. Computation of rate and volume of stream depletion by wells, by C. T. Jenkins: USGS--TWRI Book 4, Chapter Dl. 1970. 17 pages. 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 and 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. t. Thatcher, V. J. Janzer, and K. W. Edwards: USGS--TWRI Book 5, Chapter A5. 1977. 95 pages. 5-Cl. Laboratory theory and methods for sediment analysis, by H. P. Guy: USGS--TWRI Book 5, Chapter Cl. 1969. 58 pages. 7-Cl. 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. Schaffranek, R. A. Baltzer, and D. E. Goldberg: USGS--TWRI Book 7, Chapter C3. 1981. 110 pages. 8-Al. Methods of measuring water levels in deep wells, by M. S. Garber and F. C. Koopman: USGS-­ TWRI Book 8, Chapter Al. 1968. 23 pages 8-B2. Calibration and maintenance of vertical-axis type current meters, by G. F. Smoot and C. E. Novak: USGS--TWRI Book 8, Chapter B2. 1968. 15 pages. 296 297 INDEX Page Page Acre-foot, definition of 12 Caguas, Lago Loiza No. 4 near mouth near 217,219,232 Adjuntas, Lago Garzas No. 1 near Caguas, Rio Bairoa near 108 dam near 207-208,220-222,225 Caguas, Rio Caguitas at Highway 30 at 107 Adjuntas, Rio Blanco near 179 Caguas, Rio Grande de Loiza at 105-106 Adjuntas, Rio Grande de Arecibo near 42 Caguas, Rio Turabo at 197 Aguada, Rio Culebra near 206 Caguitas above mouth, Rio 197 Aguada, Rio Culebrinas near 192-193,206 at Highway 30 at Caguas 107 Aguada, Rio Ingenio near 206 Calabazas, Rio Guayangs at 202 Agua at Playa de Ponce, Quebrada del 205 Cambalache near Loiza, Quebrada 198 Aguas Buenas, Rio de Bayamon near 91 Camp Eliza Colberg, Rio Espiritu Santo at 199 Aguas Claras basin, Quebrada, low-flow partial-record Campo Rico, Rio Can6vanas near 115 stations in 200 Camuy basin, Rio, low-flow partial-record stations Aguas Claras near Ceiba, Quebrada 200 in 195 Aguas Verdes basin, Quebrada, ground-water records Camuy at Capaez, Rio 195 in 258 Canal Principal de Diversiones at Lago de Guajataca 37 Algae, definition of 12 Canal Principal de Riego Valle de Lajas basin, gaging Analyses of samples collected at miscellaneous sites 234-235 stations records in 164 Analyses of samples collected at water-quality Candelero at Highway 906, Rio 202 partial-record stations in Puerto Rico 207-233 at mouth 202 Ant6n Ruiz at mouth, Rio 201 Candelero basin, Rio, low-flow partial-record at Pasto Viejo 201 stations in 202 Ant6n Ruiz basin, Rio, low-flow partial-record Can6vanas at La Marina, Rio 198 stations in 201 at Loiza 198 Afiasco, Rio Grande de Afiasco near 187-188 near Campo Rico 115 Afiasco Arriba, Rio Grande de Afiasco at 206 Canovanillas at Carruzos 198 Apeadero basin, Rio, ground-water records in 255 at Loiza 198 Aquifer, definition of 12 Cafias above Lago Loiza, Rio 198 Arroyo, Rio Nigua at 203 below Las Americas Avenue 205 Arroyo, Quebrada Coroz6n near 203 near Santa Isabel 204 Arroyo, Quebrada Salada near 203 Cafias basin, Rio, low-flow partial-record stations Artesian, definition of 12 in 204 Arus, Rio Inabon near 204 Calk de Quebrada Catalina at Bayam6n 195 Arus, Rio Jacaguas at 204 Carlo Santiago near Central Roig 203 Caonillas above Lago Caonillas near Jayuya, Rio 44 Bairoa at mouth, Rio 197 Capaez, Rio Camuy at 195 near Caguas 108 Caparra Heights, Quebrada Margarita at 196 Bacteria, definition of 12 Carolina, Quebrada Blasina near 102,196 Bahia de San Juan No. 5 at San Juan 99 Carolina, Rio Grande de Loiza above 198 Balboa, Rio Yaguez at 206 Carolina, Rio Grande de Loiza at 198 BayamOn, at Flood Channel at Bayam6n, Rio de 93-94,196 Carruzos, Rio Canovanillas at 198 near Aguas Buenas 91 Castafier, Lago Guayo near 181 Bayam6n basin, Rio de, gaging station records in 91-94 Castafier, Lago Prieto near 182 ground-water records in 249 Castafier, Lago Yahuecas near 180 low-flow partial-record stations in 196 Catafio, Rio Hondo at Flood Channel near 90 Bayamon, Calm de Quebrada Catalina at 195 Cayaguas at Cerro Gordo, Rio 104,234-235 Bayamon, Quebrada Santa Catalina at 195 Cayey, Lago Carite No. 1 near dam Bayam6n, Rio Hondo at 195 near 215-216,218,220-222,229 Bayamon, Rio Guaynabo near 92 Cayey, Lago Carite No. 3 on Rio de la Plata near..215-216,228 Bayam6n, Rio Hondo II near 196 Ceiba at Ceiba, Quebrada 200 Beatriz above Rio Turabo, Quebrada 197 Ceiba basin, Quebrada, low-flow partial-record Beatriz, Rio Turabo below Quebrada 197 stations in 200 Bed material, definition of 13 Ceiba Norte, Rio Gurabo at 197 Benthic invertebrates analyses of samples collected Ceiba, Quebrada Aguas Claras near 200 at water-quality partial-record stations 210 Cells/volume, definition of 13 Biochemical oxygen demand, definition of 13 Central Cambalache, Rio Grande de Arecibo at 54-55 Biological data, qualitative and associated Central Guamani, Rio Seco near 204 quantitative analyses of 210,223-233 Central Pellejas, Rio Pellejas at 209-211 Blanco at mouth, Rio 201 Central Pellejas, Rio Vivi near 212-214 at Naguabo 234-235 Central Roig, Carlo Santiago near 203 at Rio Blanco 201 Central Roig, Rio Guayanes at 202 at Rio Blanco Pump House 234-235 Central Rufina, Rio Guayanilla at 160-161 below La Fe 201 Central San Vicente, Drainage Ditch at Rio Cibuco near Adjuntas 179 below 77 near Florida 132,234-235 Central San Vicente, Rio Cibuco below 78-79 Blanco basin, Rio analyses of samples collected at Cerrillos near Ponce, Rio 153-154 miscellaneous sites 234-235 Cerro Gordo, Rio Cayaguas at 104,234-235 gaging station records in 131-132 Cfs-day, definition of 13 low-flow partial-record stations in 201 Charco Hondo, Rio Tanam8 at 52-53 Blasina basin, Quebrada, gaging stations records in 102 Chico at Providencia, Rio 144,203 low-flow partial-record stations in 196 Chico basin, Rio, gaging stations records in 144 Blasina near Carolina, Quebrada 102,196 Chlorophyll, definition of 13 Blue-green algae, definition of 17 Ciales, Rio Cialitos at Highway 649 at 64 Bonne Resolution Gut at Bonne Resolution, Ciales, Rio Grande de Manati at 61-62 St. Thomas, VI 269-272 Ciales, Rio Grande de Manati at Highway 149 at 63 Boquer6n at BoquerOn, Quebrada 205 Cialitos at Highway 649 at Ciales, Rio 64 Boquer6n basin, Quebrada, low-flow partial-record Cibuco at Vega Baja, Rio 74-75 stations in 205 below Central San Vicente 78-79 Boquer6n, Lajas Irrigation Canal near 164 below Corozal 72-73 Borinquen, Rio Turabo at 197 Cibuco basin, gaging-station records in 72-79 Botija at Highway 31, Quebrada 200 ground-water records in 244-246 Botija basin, Quebrada, low-flow partial-record low-flow partial-record stations in 195 stations in 200 Coamo basin, Rio, gaging-station records in 150 Bottom material, definition of 13 ground-water records in 256-260 Bucang basin, Rio, gaging station records in 153-154 low-flow partial-record stations 204 ground-water records in 263 Coamo near Coamo, Rio 150 low-flow partial-record stations in 205 near Santa Isabel 204 Bucang at Ponce, Rio 205 Colonia Dolores, Rio Herrera near 198 298 Page Colonia Laura, Rio Guayangs near 202 Comerio, Rio de la Plata near 84 Control, definition of 13 Control structure, definition of 13 Cooperation 1-2 CorozOn basin, Quebrada, low-flow partial-record stations in 203 Coroz6n near Arroyo, Quebrada 203 Corozal, Rio Cibuco below 72-73 Crest-stage station, definition of 13 crest-stage partial-record stations, discharge at 206 Cubic feet per second per square mile, definition of 13 Cubic foot per second, definition of 13 Culebra basin, Rio, low-flow partial-record stations in 206 Culebra near Aguada, Rio 206 Culebrinas, at Highway 404 near Moca, Rio 191 near Aguada 191-193,206 near San Sebastian 190 Culebrinas basin, Rio, gaging station records in 190-193 ground-water records in 266 low-flow partial-record stations in 206 Daguao above mouth, Rio 200 at Daguao 200 Daguao, Quebrada Palma at 200 Daguao basin, Rio, low-flow partial-record stations in 200 Damsite, Lago Loiza at 113,198 Definition of terms 12-19 De los Cedros basin, Quebrada, low-flow partial- record stations in 195 De los Cedros near Isabela, Quebrada 195 Demajagua at Demajagua, Rio 200 Demajagua basin, Rio, low-flow partial-record station in 200 Descalabrado basin, Rio, low-flow partial-record stations in 204 Descalabrado near Santa Isabel, Rio 204 Diatoms, definition of 17 Discharge at crest-stage partial-record stations 206 Discharge at low-flow partial-record stations 195-206 Discharge at partial-record stations in Puerto Rico 195-206 Discharge, definition of 13 Dissolved, definition of 14 Diversity index, definition of 14 Downstream order and station number 19-20 Drainage area, definition of 14 Drainage basin, definition of 14 Drainage ditch at Rio Cibuco below Central San Vicente 77 below Warner Lambert Lab. near Sabana 76 El Mango, Rio Gurabo at 197 El Verde, Quebrada Sonadora near 118 El Verde, Quebrada Toronja at 119 El Verde, Rio Grande near 199 Ensenada, Lajas Drainage Canal near 165 Espiritu Santo basin, Rio, gaging station records in 118-121 low-flow partial-record stations in 199 Espiritu Santo at Camp Eliza Colberg, Rio 199 near Rio Grande 120-121 Explanation of ground-water level records 27-28 Explanation of stage and water-discharge records 21-25 Explanation of water-quality records 25-27 Fajardo at Fajardo, Rio 200 at Vapor below confluence 200 below Fajardo 130 near Fajardo 125-129 Fajardo at Highway 194, Quebrada 200 Fajardo basin, Quebrada, low-flow partial-record stations in 200 Fajardo basin, Rio, gaging station records in 125-130 low-flow partial-record stations in 200 Fajardo, Quebrada Mata Redonda near 200 Fecal coliform bacteria, definition of 12 Fecal streptococcal bacteria, definition of 12 Florida, Rio Blanco near 132,234-235 Florida, Rio Grande de Areclbo below Lago Dos Bocas near 45 Gage-height, definition of 14 Gaging station, definition of 14 Grande at La Gloria, Quebrada 198 Grande basin, Rio, low-flow partial-record stations in 206 INDEX Page Grande de Aliasco basin, Rio, gaging station records in 179-188 ground-water records in 265 low-flow partial-record stations in 206 Grande de Anasco, at Anasco Arriba, Rio 206 near Ailasco 187-188 near Lares 183 near San Sebastian 184-186 Grande de Arecibo at Central Cambalache, Rio 54-55 below Lago Dos Bocas near Florida 45 near Adjuntas 42 near Utuado 43 Grande de Arecibo basin, Rio, analyses of samples collected at miscellaneous sites 234-235 gaging station records in 42-55 ground-water records in 240 water-quality partial-record stations in 207-216,218,220-222,225-227 Grande de Loiza above Carolina, Rio 198 at Caguas 105-106 at Carolina 198 at Highway 183 196 at Jagual 196 at Quebrada Arenas 103 at San Lorenzo North 196 below Rio Emajagua 196 below Trujillo Alto 114 Grande de Loiza basin, Rio, analyses of samples collected at miscellaneous sites 234-235 gaging station records in 102-115 ground-water records in 250 low-flow partial-record stations in 196-198 water-quality partial-record stations in....217-222,232-233 Grande de Manati at Ciales, Rio 61-62 at Highway 149 at Ciales 63 at Highway 2 near Manati 65-68 near Morovis 59-60 Grande de Manati basin, Rio, gaging station records in 58-68 ground-water records in 241-243 Grande de Patillas at Patillas, Rio 203 at Providencia 203 below Quebrada Sonadora 203 near Patillas 145-147 Grande de Patillas basin, Rio, gaging station records in 145-147 low-flow partial-record stations in 203 Grande at Rio Grande, Rio 199 near El Verde 199 near Rincon 206 Green algae, definition of 17 Ground-water levels 238-266,280-293 Ground-water records for Puerto Rico 238-266 Ground-water records for Virgin Islands 280-293 Ground-water records for Virgin Islands, Quality of 294 Ground-water level records, explanation of 27-28 Ground-water station, definition of 14 Ground-water stations in Puerto Rico, map showing location of 238 Ground-water wells in U.S. Virgin Islands, map showing location of 280 Guadiana near Naranjito, Rio 85 Guajataca above mouth near Quebradillas, Rio 38,195 at Lares 36 Guajataca basin, Rio, gaging station records in 36-38 ground-water records in 239 low-flow partial-record stations in 195 water-quality partial-record stations in.. .207-208,220-224 Guamani basin, Rio, ground-water records in 253 low-flow partial-record stations in 204 Guamani near Guayama, Rio 204 Guanajibo below San German, Rio 205 near Hormigueros 173-175 near San German 170 Guanajibo basin, Rio, gaging station records in 170-175 ground-water records in 263-264 low-flow partial-record stations in 205 Gugnica, Rio Loco at 166-167 Gugnica, Rio Loco near 205 Guayama, Rio Guamani near 204 Guayangs above mouth at Playa de Guayangs, Rio 139-140 at Calabazas 202 at Central Roig 202 at Playa de Guayanes 202 at Yabucoz 137-138,202 below Rio Arenas 202 near Colonia Laura 202 near mouth near Playa de Guayangs 202 299 INDEX Page Page Guayanes basin, Rio, gaging station records in 137-140 Lago Dos Bocas No. 1 near dam near ground-water records in 252-254 Utuado 215-216,218,220-222,227 low-flow partial-record stations in 202 No. 3 at west branch near Utuado 215-216,226 Guayanilla at Central Rufina, Rio 160-161 Lago Garzas No. 1 near dam near near Guayanilla 159 Adjuntas 207-208,220-222,225 Guayanilla basin, Rio, gaging station records in 159-161 Lago Guayo near Castafier 181 ground-water records in 261 Lago La Plata No. 3 near dam near Guaynabo near Bayamon, Rio 92 Naranjito 217-222,231 Guinea Gut at Bethany, St. John, VI 276 No. 5 near mouth near Naranjito 217,219,230 Gurabo at Gurabo, Rio 110-111 Lago Loiza at damsite 113,198 at Ceiba Norte 197 No. 4 near mouth near Caguas 217,219,232 at El Mango 197 No. 7 near dam near Trujillo Alto 217-222,233 below Highway 943 197 Lago Loiza, Rio Cafias above 198 near Gurabo 112 Lago Prieto near Castafier 182 near Juncos 197 Lago Yahuecas near Castafier 180 Laguna San Josg No. 2 at San Juan 98 Hacienda San Isidro, Rio Jacaboa at 203 Laguna Tortuguero basin, gaging station records in 69 Hardness, definition of 14 Laguna Tortuguero outlet near Vega Baja 69 Hato Rey, Rio Piedras at 97 Lajas at Toa Alta, Rio 195 Herrera near Colonia Dolores, Rio 198 Lajas Drainage Canal near Ensenada 165 near Loiza 198 Lajas Irrigation Canal near Boquer6n 164 Herrera basin, Rio, low-flow partial-record stations La Marina, Rio Can6vanas at 198 in 198 La Plata at Proyecto La Plata, Rio de 82-83 Honda at Las Torres, Quebrada 197 at Toa Alta 86-88 Hondo at Bayam6n, Rio 195 near Comerio 84 at Flood Channel near Catafio, Rio 90 La Plata basin, Rio de, gaging station records in 82-88 Hondo II near Bayamon, Rio 196 ground-water records in 247-248 Hondo basin, Rio, gaging station records in 90 low-flow partial-record stations in 195 low-flow partial-record stations in 195-196 water-quality partial-record stations in....215-222,228-231 Hormigueros, Rio Guanajibo near 173-175 Lares, Rio Grande de Afiasco near 183 Hormigueros, Rio Rosario near 172 Lares, Rio Guajataca at 36 Humacao at Highway 3 at Humacao, Rio 134-136 Las Bambuas at mouth, Quebrada 196 at Las Piedras 201 Las Piedras, Rio Humacao at 201 Flood Channel near mouth 201 Las Piedras, Rio Valenciano near 197 near Humacao 201 Las Torres, Quebrada Honda at 197 Humacao basin, Rio, gaging station records in 134-136 Levels, ground-water 238-266,280-293 low-flow partial-record stations in 201 Limones near Yabucoa, Rio 202 Hydrologic conditions, summary of 2-11 Lizas, Rio Maunabo at 141 Loco at Gugnica, Rio 166-167 Icacos near Naguabo, Rio 131 near Gugnica 205 Inabein at Real Abajo, Rio 152 Loco basin, Rio, low-flow partial-record stations in 205 near Arus 204 gaging station records in 165-167 InabOn basin, Rio, gaging station records in 152 Loiza, Quebrada Cambalache near 198 low-flow partial-record stations in 204 Macang at Magas Arriba, Rio 205 Indio near Vega Baja, Rio 195 Macang basin, Rio, low-flow partial-record stations Ingenio basin, Rio, ground-water records in 266 in 205 low-flow partial-record stations in 206 Magas Arriba, Rio Macang at 205 Ingenio basin, Rio del, low-flow partial-record Majada at Rabo del Buey, Rio 204 stations in 202 Mameyes at Mameyes, Rio 199 Ingenio near Aguada, Rio 206 at Highway 191 at Mameyes 123 Ingenio near Playa de Guayanes, Rio del 202 near Sabana 122,199 near Yabucoa 202 Mameyes basin, Rio, gaging station records in 122-123 Instantaneous discharge, definition of 14 low-flow partial-record stations in 199 Introduction 1 Manati, Rio Grande de Manati at Highway 2 near 65-68 Isabela, Quebrada de los Cedros near 195 Maps: Jacaboa at Hacienda San Isidro, Rio 203 Location of ground-water stations in Puerto Rico 238 Jacaboa basin, Rio, low-flow partial-record stations Location of ground-water wells in U.S. Virgin in 203 Islands 280 Jacaguas at Arus, Rio 204 Location of low7flow partial-record stations in Jacaguas basin, Rio, ground-water records in 257 Eastern Puerto Rico 32 low-flow, partial-record stations in 204 Location of partial-record stations in Central Jagual, Rio Grande de Loiza at 196 and Western Puerto Rico 33 Jauca, Rio Jueyes near 204 Location of surface-water stations in the U.S. Jayuya, Rio Caonillas above Lago Caonillas near 44 Virgin Islands 268 Jimenez near Rio Grande, Quebrada 199 Location of surface-water stations in Puerto Rico 30 Jobos, Rio Melania near 204 Location of water-quality stations in Puerto Rico 31 Jolly Hill Gut at Jolly Hill, St. Croix, VI 277 Rainfall distribution during April 18, 1983 in the Josefina at Pifieiro Avenue, Quebrada 196 U.S. Virgin Islands 7 Juan Gonzalez near Rio Grande, Quebrada 199 Rio Camuy basin 39 Juan Martin above mouth, Rio 199 Rio Cibuco basin 71 at Highway 3, Tributary to 199 Rio Culebrinas basin 189 Juan Martin basin, Rio, low-flow partial-record Rio Grande de Arecibo basin 41 stations in 199-200 Rio Grande de Loiza basin 101 Jueyes basin, Rio, low-flow partial-record stations Rio Grande de Manati basin 57 in 204 Rio Guajataca basin 35 Jueyes near Jauca, Rio 204 Rio Guanajibo basin 169 Juncos, Rio Gurabo near 197 Rio Herrera to Rio Ant6n Ruiz basins 117 Juncos, Rio Valenciano near 107 Rio Hondo to Rio Puerto Nuevo basins 89 Rio Humacao to Rio Seco basins 133 La Fe, Rio Blanco below 201 Rio InabOn to Rio Loco basins 151 La Fe, Quebrada Vaca below 201 Rio de la Plata basin 81 La Gloria, Quebrada Grande at 198 Rio Salinas to Rio Jacaguas basins 149 Lago Carite No.1 near dam near Cayey..215-216,218,220-222,229 Rio Yagfiez and Rio Grande de Afiasco basins 177 No. 3 on Rio de la Plata near Cayey 215-216,228 Maracuta at Trujillo Bajo, Quebrada 198 Lago de Guajataca, Canal Principal de Diversiones at. 37 Margarita at Caparra Heights, Quebrada 196 No. 1 near dam near Quebradillas 207-208,220-222,224 Mariana at Patagonia, Quebrada 201 No. 3 near mouth near Quebradillas 207-208,223 300 INDEX Page Mats de Plgtano basin, Quebrada, low-flow partial- record stations in 199 Mata de Plgtano near Luquillo, Quebrada 199 Mata Redonda near Fajardo, Quebrada 200 Matilde basin, Rio, low-flow partial-record stations in 205 Maunabo at Lizas, Rio 141 at Maunabo 142-143,203 Maunabo basin, Rio, gaging station records in 141-143 low-flow partial-record stations in 203 ground-water records in 254 Mayagiiez, Rio Yaguez near 178 Mean concentration, definition of 18 Mean discharge, definition of 14 Melania basin, Rio, low-flow partial-record stations in 204 Melania near Jobos, Rio 204 Micrograms per gram, definition of 15 Micrograms per liter, definition of 15 Milligrams per liter, definition of 15 Miscellaneous sites, Analyses of samples collected at 234-235 Miscellaneous sites, numbering system for wells and 20 Moca, Rio Culebrinas at Highway 404 near 191 Morovis, Rio Grande de Manati near 59-60 Naguabo, Rio Blanco at 234-235 Naguabo, Rio Icacos near 131 Naguabo, Rio Santiago at 201 Naranjito, Lago La Plata No. 3 near dam near 217-222,231 Naranjito, Lago La Plata No. 5 near mouth near 217,219,230 Naranjito, Rio Guadiana near 85 NASQAN, definition of 20-21 National stream-quality accounting network 20-21 Networks and programs, special 20-21 Nigua at Arroyo, Rio 203 Nigua basin, Rio, ground-water records in 252 low-flow partial-record stations in 203 Numbering system for wells and miscellaneous sites... 20 Organism, definition of 15 Organism count/area, definition of 15 Organism count/volume, definition of 15 Orocovis, Rio Orocovis near 58 Palma at Daguao, Quebrada 200 Palma basin, Quebrada, low-flow partial-record stations in 200 Palomas, Quebrada Susga at 205 Partial record station, definition of 16 Partial-record stations, Discharge at 195-206 Partial-record stations in Central and Western Puerto Rico, map showing location of 33 Particle size, definition of 16 Particle-size classification, definition of 16 Pasto Viejo, Rio Anton Ruiz at 201 Patagonia, Quebrada Mariana at 201 Patillas, Rio Garnde de Patillas at 203 Patillas, Rio Grande de Patillas near 145-147 PCBs, definition of 17 Pellejas at Central Pellejas, Rio 209-211 Pellejas near Utuado, Rio 234-235 Percent composition, definition of 16 Pesticides analyses of samples collected at water- quality partial-record stations 220-222 Pesticides, definition of 16 Pesticide program 21 Phytoplankton analyses of samples collected at water- quality partial-record stations 223-233 Phytoplankton, definition of 16 Piedras, at Hato Rey, Rio 97 at Rio Piedras 196 near Rio Piedras 95-96 Pineiro Avenue, Quebrada Josefina at 196 Pitahaya basin, Rio, low-flow partial-record stations in 199 Pitahaya near Luquillo, Rio 199 Plankton, definition of 16 Playa de Guayangs, Rio del Ingenio near 202 Playa de Guayangs, Rio Guayanes above mouth at 139-140 Playa de Guayangs, Rio Guayangs at 202 Playa de Guayangs, Rio Guayangs near mouth near 202 Playa de Ponce, Quebrada del Agua at 205 Polychlorinated biphenyls, definition of 17 Ponce, Rio Bucang at 205 Ponce, Rio Cerrillos near 153-154 Page Ponce, Rio Portugugs at 157-158 Ponce, Rio Portugugs at Highway 14 at 206 Ponce, Rio Portugugs at Highway 2 by-pass at 205 Ponce, Rio Portugugs near 155-156 Portugugs at Highway 14 at Ponce, Rio 206 at Highway 2 by-pass at Ponce 205 at Ponce 157-158 near Ponce 155-156 Portugugs basin, Rio, crest-stage partial-record station in 206 gaging station records in 155-158 ground-water records in 260 Programs, special networks and 20-21 Providencia, Rio Chico at 144,203 Providencia, Rio Grande de Patillas at 203 Proyecto La Plata, Rio de La Plata at 82-83 Publications on techniques of water-resources investigations 295 Puerto Nuevo basin, Rio, gaging station records in 95-99 ground-water records in 249 low-flow partial-record stations in 196 Qualitative and associated quantitative analyses of biological data 210,223-233 Quality of ground water for Virgin Islands 294 Quality-of-water records for Puerto Rico, surface and 29-235 Quebrada Arenas, Rio Grande de Loiza at 103 Quebrada Sonadora, Rio Grande de Patillas below 203 Quebradillas, Lago Guajataca No. 1 near dam near 207-208,220-222,224 Quebradillas, Lago Guajataca No. 3 near mouth ... 207-208,223 Quebradillas, Rio Guajataca above mouth near 38,195 Rabo del Buey, Rio Majada at 204 Real Abajo, Rio InabOn at 152 Records for Puerto Rico, ground water 238-266 Records for Virgin Islands, ground-water 280-293 Rinc6n, Rio Grande near 206 Rio Arenas, Rio Guayangs below 202 Rio Emajagua, Rio Grande de Loiza below 196 Rio Grande, Quebrada Jimgnez near 199 Rio Grande, Quebrada Juan Gonzglez near 199 Rio Grande, Rio Espiritu Santo near 120-121 Rosario at Rosario, Rio 171 near Hormigueros 172 Runoff, in inches, definition of 17 Sabana at Luquillo, Rio 199 at Sabana 124 Sabana basin, Rio, gaging station records in 124 low-flow partial-record stations in 199 Sabana, Drainage ditch below Warner Lambert Lab. near 76 Sabana, Rio Mameyes near 122,199 Salads basin, Quebrada, low-flow partial-record stations in 203 Salada near Arroyo, Quebrada 203 Salinas at Salinas, Rio 203 Salinas basin, Rio, ground-water records in 255-256 low-flow partial-record stations in 204 San Germgn, Rio Guanajibo below 205 San Germgn, Rio Guanajibo near 170 San Juan, Bahia de San Juan no. 5 at 99 San Juan, Laguna San Josg No. 2 at 98 San Lorenzo Norte, Rio Grande de Loiza at 196 San Sebastign, Rio Culebrinas near 190 San Sebastian, Rio Grande de Anasco near 184-186 Santa Catalina at Bayamon, Quebrada 195 Santa Isabel, Rio Canas near 204 Santa Isabel, Rio Coamo near 204 Santa Isabel, Rio Descalabrado near 204 Santiago at Naguabo, Rio 201 Santiago at Highway 3, Cano 203 near Central Roig 203 Santiago basin, Cain), low-flow partial-record stations in 203 Santiago basin, Rio, low-flow partial-record stations in 201 Seco basin, Rio, ground-water records in 250-251 low-flow partial-record stations in 204 Seco near Central Guamani, Rio 204 Sediment 27 Sediment, definition of 17 Sonadora near El Verde, Quebrada 118 Solute, definition of 18 Special network and programs 20-21 Specific conductance, definition of Stage and water-discharge records, explanation of Stage-discharge relation, definition of Station number, downstream order and St. Croix, VI, Jolly Hill Gut at Jolly Hill St. John, VI, Guinea Gut at Bethany Streamflow, definition of St. Thomas, VI, Bonne Resolution Gut at Bonne Resolution St. Thomas, VI, Turpentine Run at Mariendal Summary of hydrologic conditions Surface and quality-of-water records for Puerto Rico Surface-water records for Virgin Islands Surface-water stations in Puerto Rico, map showing location of Surface-water stations in U.S. Virgin Islands, map showing location of Surficial bed material, definition of Suspended, definition of Suspended sediment, definition of Suspended-sediment concentration, definition of Suspended-sediment discharge, definition of Suspended-sediment load, definition of Susga at Palomas, Quebrada 301 INDEX Page Water-quality partial-record stations, phytoplankton 21-25 analyses of samples collected at 223-233 18 Water-quality records, explanation of 25-27 19-20 Water-quality stations in Puerto Rico, map 277 showing location of 31 276 Water-resources investigations, publications on 18 techniques of 295 Water temperature 26 269-272 Water year, definition of 19 273-275 Weighted average, definition of 19 2-11 Wells: 29-235 Aguas Verdes basin, Quebrada 268-277 Well 124 - Coqui 2 258 Apeadero basin, Rio 30 Well 125 - Patillas STP 255 BayamOn basin, Rio de 268 Well 42 - Cidra 2 249 18 Well 66 - Sabana Seca 249 18 Bucang basin, Rio 17 Well 141 - Restaurada 8A 263 17 Cibuco basin, Rio 17 Well 62 - Vega Alta 1 244 17 Well 70 - Sabana Hoyos 244 205 Well 151 - Rice Program #3 245 Well 155 - La Trocha 245 205 Well 156 - El Criollo #1 245 Well 167 - USGS Observation Well #3 246 205 Well 168 - Rice Program #4 246 52-53 Well 169 - Rice Program #5 246 46-51 Coamo basin, Rio 19 Well 10 - Santa Isabel 1 256 Well 87 - Alomar 1 257 295 Well 144 - Jauca south well, site 1 258 26 Well 145 - Jauca north well, site 1 258 12-19 Well 146 Hacienda Alomar west well, site 3 259 18 Well 147 - Hacienda Alomar east well, site 3 259 86-88 Well 148 - Playa Santa Isabel east well, site 2 259 195 Well 149 - Playa Santa Isabel west well, site 2 260 18 Culebrinas basin, Rio 18 Well 83 - San Sebastign 266 119 Grande de Afiasco basin, Rio 12-13 Well 53 - Mayaguez Airport 265 19 Grande de Arecibo basin, Rio 16 Well 86 - Adjuntas 240 18 Well 123 - Jayuya 3 240 199 Well 161 - Santana #2 240 201 Grande de Loiza basin, Rio 21 Well 50 - Gurabo 250 Well 52 - Bairoa 250 Grande de Manati basin, Rio Well 68 - Manati 2 241 Well 71 - Florida Afuera, Barceloneta 241 Well 135 - Lederle 242 Well 142 - Morgn Sim6 243 Well 166 - Manati (new well) 243 Guamani basin, Rio Well 89 - Phillips observation well 3 253 Guajataca basin, Rio Well 164 - Rocha Moca 239 Well 165 - Mateo Perez, Bo. Salto 239 Guanajibo basin, Rio Well 40 - Rosario 263 Well 43 - Central Rochelaise 264 Well 143 - Vivoni, Hacienda Amistad 264 Guayangs basin, Rio Well 31 - Central Roig 252 Well 95 - USGS TW-5 or Yabucoa 10 253 Well 96 - USGS TW-2 or Yabucoa 7 254 Guayanilla basin, Rio Well 27 - Quebradas 261 Well 74 - Guayanilla 261 Ingenio basin, Rio Well 58 - Aguada 266 Jacaguas basin, Rio Well 88 - Hacienda Potgla 257 La Plata basin, Rio de Well 33 - Cayey 10 247 Well 37 - Barrio RincOn de Cidra 247 Well 38 - Barrio Robles 247 Well 67 - Campanilla 248 Well 69 - Higuillar 248 Well 150 - Monterey Forestal 248 Maunabo basin, Rio Well 122 - Maunabo Calzada 254 Tallaboa at Tallaboa, Rio Tallaboa basin, Rio, low-flow partial-record stations in Tanamg at Charco Hondo, Rio Tanamg near Utuado, Rio Taxonomy, definition of Techniques of water-resources investigations, publications on Temperature, water Terms, definition of Time-weighted average, definition of Toa Alta, Rio de La Plata at Toa Alta, Rio Lajas at Tons per acre-foot, definition of Tons per day, definition of Toronja at El Verde, Quebrada Total coliform bacteria, definition of Total load, definition of Total organism count, definition of Total sediment discharge, definition of Tributary to Rio Juan Martin at Highway 3 Tributary to Rio Santiago at Highway 192 Tritium network Trujillo Alto, Lago Loiza No. 7 near dam near 217-222,233 Trujillo Alto, Rio Grande de Loiza below 114 Trujillo Bajo, Quebrada Maracuta at 198 Turabo at Borinquen, Rio 197 Turabo at Caguas, Rio 197 Turabo below Quebrada Beatriz, Rio 197 Turabo, Quebrada Beatriz above Rio 197 Turpentine Run at Mariendal, St. Thomas, VI 273-275 Utuado, Lago Dos Bocas No. 1 near dam near 215-216,220-222,227 Utuado, Lago Dos Bocas No. 3 at west branch near..215-216,226 Utuado, Rio Grande de Arecibo near 43 Utuado, Rio Pellejas near 234-235 Utuado, Rio Tanamg near 46-51 Vaca below La Fe, Quebrada 201 Valenciano at mouth, Rio 197 near Juncos 109 near Las Piedras 197 Vapor below confluence, Rio Fajardo at 200 Vega Baja, Laguna Tortuguero outlet near 69 Vega Baja, Rio Cibuco at 74-75 Vega Baja, Rio Indio near 195 Vivi near Central Pellejas, Rio 212-214 Water analysis 26 Water-discharge records, explanation of stage and 21-25 Water-quality partial-record stations in Puerto Rico, analyses of samples collected at 207-233 Water-quality partial-record stations, benthic invertebrates analyses of samples collected at 210 Water-quality partial-record stations, pesticides analyses of samples collected at 220-222 302 Nigua basin, Rio Well 15 - Pitahaya 1 Portugu6s basin, Rio Well 21 - Alhambra Puerto Nuevo basin, Rio Well 65 - Hato Rey Central, McCraken Salinas basin, Rio Well 1 - Mar Negro Well 8 - Salinas 1 Well 18 - Cocos Well 19 - Theater 1 Seco basin, Rio Well 2 - Puente Jobos Well 3 - Jobos Well 6 - Juana 5 St. Croix Well 1 - Fairplains 6 (FP6) Well 2 - USGS-10, Fairplains 2 (FP2) Well 3 - Golden Grove 6 (PW6) Well 4 - Golden Grove 1 (PW1) Well 5 - Mahogany Road 3 Well 6 - Adventure 28 Well 7 - Concordia 14 Well 8 - Concordia 1 (main pump house) Well 9 - Concordia 7 Well 10 - Barren Spot 5 (PWD-5) St. John Well 1 - NPS-2 (Cruz Bay) Well 2 - NPS-5 (Trunk Bay) Well 3 - NPS-6 (Cinnamon Bay) Well 4 - USGS-15 (Calabash Boom) Well 5 - DPW-6 Well 6 - DPW-5 Well 7 - DPW-4 Well 8 - DPW-3 Well 9 - DPW-2 INDEX Page Page Well 10 - DPW-1 293 252 Well 11 - Guinea Gut Well 293 St. Thomas 260 Well 1 - USGS-8 (Family well-Thatch Farm) 286 Well 2 - Mahogany 15 286 249 Well 3 - Mahogany 16 286 Well 4 - Mahogany 17 287 255 Well 5 - Donoe 3 287 255 Well 6 - Grade School 3 288 256 256 YagUez basin, Rio Well 45 - Well 1, MayagUez 265 250 Yauco basin, Rio 251 Well lb - Central San Francisco 260 251 Well 131 Yauco 1 or UCC 2 261 Well 132 - Yauco 2 262 281 Well 134 - Yauco 4 or UCC 1 262 281 Wells and miscellaneous sites, numbering system 282 for 20 282 WRD, definition of 19 283 WSP, definition of 19 283 284 Yabucoa, Rio del Ingenio near 202 284 Yabucoa, Rio Guayangs at 137-138,202 285 202 Yabucoa, Rio Limones near 285 206 YagUez at Balboa, Rio near Mayaguez 178 289 YagUez basin, Rio, gaging station records in 178 289 ground-water records in 265 290 low-flow partial-record stations in 206 290 Yauco, above Diversi6n Monserrate near Yauco, Rio 162 291 at Pueblo Sur at Yauco 205 291 near Yauco 163 292 Yauco basin, Rio, gaging station records in 162-163 292 ground-water records in 260-262 292 low-flow partial-record stations in 205 111111111111111111 Introduction, definition of terms, and explanation of data (1) Continuous surface-water stations in Puerto Rico (30) Water-quality stations in Puerto Rico (31) Low-flow partial-record stations in Puerto Rico (32) Rio Guajataca basin (35) MARGIN INDEX Rio Camuy basin (39) To use, bend book and follow margin index label to page Rio Grande de Arecibo basin (41) with black edge marker. Rio Grande de Manati basin (57) I Rio Cibuco basin (71) Rio de la Plata basin (81) Rio Hondo, Rio de Bayamdn, and Rio Puerto Nuevo basins (89) Rio Grande de Loiza basin (101) Northeastern river basins - Rio Herrera to Rio Antdn Ruiz (117) Southeastern river basins - Rio Humacao to Rio Seco (133) South coast river basins - Rio Salinas to Rio Jacaguas (149) South coast river basins - Rio !nabOn to Rio Loco (151) Rio Guanajibo basin (169) Rio Yaguez and Rio Grande de Masco basins (177) Rio Culebrinas basin (189) Partial-record stations (195) Water-quality partial-record stations (207) Ground-water stations in Puerto Rico (238) Surface-water stations in the U.S. Virgin Islands (268) Ground-water stations in the U.S. Virgin Islands (280) Publications on techniques of water-resources investigations (295) Index (297) U.S. GOVERNMENT PRINTING OFFICE: 1984-751-456 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). This report contains both the inch-pound and SI unit equivalents in the station manuscript descriptions. Multiply inch-pound units inches (in) feet (ft) miles (mi) acres square miles (mil) gallons (gal) million gallons cubic feet (ft') cfs-days acre-feet (acre-ft) cubic feet per second (ft3 /s) gallons per minute (gal/min) million gallons per day tons (short) By Length 2.54x10' 2.54x10-2 3.048x10-' 1.609x10° Area 4.047x103 4.047x10-' 4.047x10-3 2.590x10° Volume 3.785x10° 3.785x10° 3.785x10-3 3.785x103 3.785x10-3 2.832x10' 2.832x10-2 2.447x103 2.447x10-3 1.233x103 1.233x HP 1.233x10-6 Flow 2.832x10' 2.832x101 2.832x10-2 6.309x10-2 6.309x10-2 6.309x10-5 4.381 x10' 4.38 lx10-2 Mass 9.072x HP To obtain SI units millimeters (mm) meters (m) meters (m) kilometers (km) square meters (m2 ) square hectometers (hm2 ) square kilometers (km2 ) square kilometers (km2 ) liters (L) cubic decimeters (dm3 ) cubic meters (m3 ) cubic meters (m3 ) cubic hectometers (hm3 ) cubic decimeters (dm3 ) cubic meters (m3 ) cubic meters (m3 ) cubic hectometers (hm3 ) cubic meters (m3 ) cubic hectometers (hm3 ) cubic kilometers (km3 ) liters per second (L/s) cubic decimeters per second (dm3 /s) cubic meters per second (m3 /s) liters per second (L/s) cubic decimeters per second (dm3 /s) cubic meters per second (m3 /s) cubic decimeters per second (dm3 /s) cubic meters per second (m3 /s) megagrams (Mg) or metric tons POSTAGE AND FEES PAID U.S. DEPARTMENT OF THE INTERIOR INT 413 US. DEPARTMENT OF THE INTERIOR USGS LIBRARY - RESTON Geological Survey GPO Box 4424 1111 111 111111 11 11 11 San Juan, PR 00936 3 1818 00454185 8 OFFICIAL BUSINESS PENALTY FOR PRIVATE USE $300 SPECIAL 4TH CLASS BOOK RATE