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Senen Guzman-Rios

Publications and source records attributed to Senen Guzman-Rios.

11 recordsLinked to original sources
USGS2006

Water-quality reconnaissance of Laguna Tortuguero, Vega Baja, Puerto Rico, March 1999-May 2000

The Laguna Tortuguero, a slightly saline to freshwater lagoon in north-central Puerto Rico, has a surface area of about 220 hectares and a mean depth of about 1.2 meters. As part of a water-quality reconnaissance, water samples were collected at about monthly and near bi-monthly intervals from March 1999 to May 2000 at four sites: three stations inside the lagoon and one station at the artificial outlet channel dredged in 1940, which connects the lagoon with the Atlantic Ocean. Physical characteristics that were determined from these water samples were pH, temperature, specific conductance, dissolved oxygen, dissolved oxygen saturation, and discharge at the outlet canal. Other water-quality constituents also were determined, including nitrogen and phosphorus species, organic carbon, chlorophyll a and b, plankton biomass, hardness, alkalinity as calcium carbonate, and major ions. Additionally, a diel study was conducted at three stations in the lagoon to obtain data on the diurnal variation of temperature, specific conductance, dissolved oxygen, and dissolved oxygen saturation. The data analysis indicates the water quality of Laguna Tortuguero complies with the Puerto Rico Environmental Quality Board standards and regulations.

Open-File Report↗
USGS2006

Water resources data, Puerto Rico and the U.S. Virgin Islands, water year 2004

The Caribbean Water Science Center of the U.S. Geological Survey (USGS), in cooperation with local and Federal agencies obtains a large amount of data pertaining to the water resources of the Commonwealth of Puerto Rico and the Territory of the U.S. Virgin Islands each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the area. To make these data readily available to interested parties outside the U.S. Geological Survey, the data are published annually in this report series entitled 'Water Resources Data for Puerto Rico and the U.S. Virgin Islands.' This report includes records on both surface and ground water. Specifically, it contains: (1) discharge records for 89 streamflow-gaging stations, daily sediment records for 13 sediment stations, stage records for 18 reservoirs, and (2) water-quality records for 20 streamflow-gaging stations, and for 38 ungaged stream sites, 13 lake sites, 2 lagoons, and 1 bay, and (3) water-level records for 72 observation wells. Water-resources data for Puerto Rico for calendar years 1958-67 were released in a series of reports entitled 'Water Records of Puerto Rico.' Water-resources data for the U.S. Virgin Islands for the calendar years 1962-69 were released in a report entitled 'Water Records of U.S. Virgin Islands.' Included were records of 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 to 2003 water years consist of one volume each and contain data for streamflow, water quality, and ground water.

Water Data Report↗
USGS2004

Surface-Water, Water-Quality, and Ground-Water Assessment of the Municipio of Mayaguez, Puerto Rico, 1999-2002

The surface-water assessment portion of this study focused on analysis of low-flow characteristics in local streams and rivers, because the supply of safe drinking water was a critical issue during recent dry periods. Low-flow characteristics were evaluated at one continuous-record gaging station based on graphical curve-fitting techniques and log-Pearson Type III frequency curves. Estimates of low-flow characteristics for 20 partial-record stations were generated using graphical-correlation techniques. Flow-duration characteristics for the continuous- and partial-record stations were estimated using the relation curves developed for the low-flow study. Stream low-flow statistics document the general hydrology under current land use, water-use, and climatic conditions. A survey of streams and rivers utilized 37 sampling stations to evaluate the sanitary quality of about 165 miles of stream channels. River and stream samples for fecal coliform and fecal streptococcus analyses were collected on two occasions at base-flow conditions. Bacteriological analyses indicate that a significant portion of the stream reaches within the municipio of Mayaguez may have fecal coliform bacteria concentrations above the water-quality goal (standard) established by the Puerto Rico Environmental Quality Board (Junta de Calidad Ambiental de Puerto Rico) for inland surface waters. Sources of fecal contamination may include: illegal discharge of sewage to storm-water drains, malfunctioning sanitary sewer ejectors, clogged and leaking sewage pipes, septic tank leakage, unfenced livestock, and runoff from livestock pens. Long-term fecal coliform data from five sampling stations located within or in the vicinity of the municipio of Mayaguez have been in compliance with the water-quality goal for fecal coliform concentration established in July 1990. Geologic, topographic, soil, hydrogeologic, and streamflow data were compiled into a database and used to divide the municipio of Mayaguez into five hydrogeologic terranes. This integrated database then was used to evaluate the ground-water potential of each hydrogeologic terrane. Lineament-trace analysis was used to help assess the ground-water development potential in the hydrogeologic terranes containing igneous rocks. Analyses suggest that areas with slopes greater than 15 degrees have relatively low ground-water development potential. The presence of fractures, independent of the topographic slope, may locally enhance the water-bearing properties in the hydrogeologic terranes containing igneous rocks. The results of this study indicate that induced streamflow generally is needed to sustain low to moderate ground-water withdrawal rates in the five hydrogeologic terranes. The ground-water flow systems in the hydrogeologic terranes are only able to sustain small withdrawal rates that rarely exceed 50 gallons per minute. Areas with a high density of fractures, as could be the case at the intersection of lineament traces in the upper parts of the Rio Ca?as and Rio Yaguez watersheds, are worthy of exploratory drilling for ground-water development.

Water-Resources Investigations Report↗
USGS1989

Suspended-sediment data in the upper Rio Grande De Loiza basin, Puerto Rico

Fluvial sediment, a widely recognized pollutant of surface water , is reducing the efficiency and useful life of almost all reservoirs in Puerto Rico. Sediment transported from the upper basin of the Rio Grande de Loiza is eventually deposited in the bottom of Lago Loiza, a water reservoir. Suspended sediment data were collected from 1983 to 1986 from a 208 sq mi area extending from the headwaters of Rio Grande de Loiza to the Lago Loiza. The drainage areas range from 0.82 sq mi to 89.8 sq mi. Results are based on three years of data from a network of five daily- record stations and five partial-record stations. A total of 2 ,114 sediment samples were collected and analyzed during the investigation. Instantaneous concentrations of suspended sediment varied from 0 to 56, 100 mg/L. Instantaneous suspended sediment loads ranged from 0 tons/day to 817,000 tons/day. A total of 152 suspended sediment samples were analyzed for particle size distribution. Suspended sediment in the streams is composed mostly of silt and clay. Sand content ranged from 6 to 80% during high flows. (Author 's abstract)

Open-File Report↗
USGS1987

Reconnaissance of Volatile Synthetic Organic Chemicals at Public Water Supply Wells Throughout Puerto Rico, November 1984-May 1985

INTRODUCTION Ground water is the principal source of drinking water for about 850,000 people in Puerto Rico (National Water Summary, 1985). Ground-water withdrawals for public supply, agricultural, and industrial water uses in Puerto Rico are about 250 million gallons per day (Mgal/d) (Torres-Sierra and Aviles, 1985). The development of the most accessible surface water supplies will result in an increasing demand for ground water. Recent investigations conducted by the U. S. Geological Survey, WRD (USGS) have shown the presence of toxic synthetic organic chemicals in ground water throughout Puerto Rico (Gomez-Gomez and Guzman-Rios, 1982). Volatile synthetic organic chemicals (VOC's) have been detected in water from public water supply wells in concentrations ranging from 1 to 500 micrograms per liter (Guzman-Rios and Quinones-Marquez, 1984 and Guzman-Rios and Quinones-Marquez, 1985). As result of these findings, pumpage was discontinued at 6 wells operated by the Puerto Rico Aqueduct and Sewer Authority (PRASA), the Commonwealth of Puerto Rico agency responsible for public-water supply. Monitoring of 10 additional wells in the vicinity of those wells is being conducted by the USGS in cooperation with PRASA. In 1985, the USGS began a comprehensive islandwide study of VOC's in drinking water. The study was conducted in cooperation with the Puerto Rico Department of Health (PRDOH) and PRASA. Samples were collected from 243 public-water supply wells operated by PRASA (flgure 1). The authors wish to acknowledge the support, assistance and cooperation of the PRASA staff throughout Puerto Rico in the sample collection effort. The authors are especially grateful to Engineer Carlos Garcia-Troche from the PRASA main office in San Juan.

Open-File Report↗