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Fernando Gómez-Gómez

Publications and source records attributed to Fernando Gómez-Gómez.

31 records · Page 2Linked to original sources
USGS1996

Sedimentation survey of Lago Dos Bocas, Puerto Rico, August 1994

Sedimentation has reduced the storage capacity of Lago Dos Bocas by approximately 43 percent over the last 52 years from 37.5 million cubic meters in 1942 to 21.3 million cubic meters in 1994. If the calculated long term sedimentation rate of 311,000 cubic meters per year remains unchanged, the water-supply storage capacity of the reservoir will be exhausted by the year 2062. Sedimentation in the reservoir has not been uniform. Three tributaries flow into the lake: the Rio Grande de Arecibo, the Rio Caonillas, and the Rio Limon. The Rio Grande de Arecibo has the largest drainage basin and was determined to deliver more sediment to the reservoir than the other two tributaries combined. Only minor amounts of sediment have deposited in the Rio Caonillas branch of the reservoir indicating that Lago Caonillas, located immediately upstream, could be the major sediment repository along the Rio Caonillas tributary. Excluding the Lago Caonillas drainage basin, the long-term sediment yield of the Rio Grande de Arecibo drainage basin is approximately one million kilograms per square kilometer per year.

Lagos Dos Bocas↗
USGS1983

Hydrologic characteristics of lagoons at San Juan, Puerto Rico, during an October 1974 tidal cycle

Flow and water-quality changes were studied during a period of intense rainfall in the San Juan Lagoon system. The study covered a 25-hour period beginning 0900 hours 22 October, 1974. Precipitation during the study period averaged 70 millimeters. Sampling stations were located at Boca de Cangrejos, the main ocean outlet; Canal Pinones between Laguna de Pinones and Laguna La Torrecilla; Canal Suarez between Laguna San Jose, connects to Laguna La Torrecilla; and Cano de Martin Pena between Laguna San Jose and Bahia de San Juan. In addition water-elevation recording gages were installed at each lagoon. Water samples from the canal stations were analyzed for organic carbon, nitrogen and phosphorus species, and suspended sediment. Specific-conductance measurements were used with the chemical data to estimate the runoff contributions of nutrients. Runoff into the lagoon, system during the study period was about 2.8 million cubic meters, or about 70 percent of the average precipitation. The runoff contributed chemical loadings to the lagoons of 95,000 kilograms total-organic carbon; 2,700 kilograms of total phosphorus; and 10,000 kilograms of total Khjeldhal nitrogen. A comparison with a prior study during which there was no significant rain, show that dry-period loadings are less than 10 percent of the wet-period loadings. At the end of the study period the system had not reached equilibrium, and the lagoons retained 80 percent of the water inflows from 50 to 90 percent of the chemical loads. Nearly 95 percent of the water outflows occurred at the Boca de Cangrejos sea outlet. The three lagoons and interconnecting canals form a very complex hydraulic system that is difficult to study using traditional techniques. A model of the system will facilitate management to improve the quality of water in the lagoons.

Open-File Report↗
USGS1980

Reconnaissance of six solid-waste disposal sites in Puerto Rico and effects on water quality

Five solid-waste landfills and an open burning dump were studied in Puerto Rico to obtain physical, chemical and biological data on leachates, give an overview of their pollution potential, and determine the adequacy of monitoring at these or similar sites. These sites are operated by the municipal governments of Arecibo, Caguas, Cayey, Humacao, Mayaguez and Guayama. The bulk of waste is of domestic origin but wastes from local industries and institutions are also handled. Data were collected between February and July 1976. Parameters measured included temperature, specific conductance, pH, color, common ions, cyanide, macronutrients (nitrogen and phosphorus species), total organic carbon, dissolved oxygen, BOD5 (biochemical oxygen demand), COD (chemical oxygen demand), total and fecal conform, trace metals, and phenols. The results obtained indicated that leachate from most sites is enriched in common ions, macronutrients, and trace metals. A sample obtained from runoff at the Cayey landfill was the only one with an acidic pH (5.8). It had a common ion concentration of 10,750 mg/L (milligrams per liter), or twice that found in leachate contained within the buried refuse. The leachate from the Caguas site had the highest common ion concentration (12,520 mg/L). Maximum values for other parameters were as follows: Temperature, 33°C (or about 10°C above ambient ground-water temperature); specific conductance, 19,200 micromhos per centimeter; color, 2,200 units; cyanide, 30 ug/L (micrograms per liter); total nitrogen, 600 mg/L; total phosphorus, 4.3 mg/L; total organic carbon, 500 mg/L; 5-day biochemical oxygen demand, 5,540 mg/L; chemical oxygen demand, 3,000 mg/L; total coliform bacteria, 410,000 colonies per 100 milliliters; fecal coliform bacteria, 14,000 colonies per 100 milliliters; total arsenic, 54 ug/L; total cadmium, 15 ug/L; total chromium, 1,600 ug/L; total lead, 1,10C ug/L; total mercury, 2.6 ug/L; total nickel, 1,300 ug/L; and total phenols, 1,100 ug/L. Pollution of water resources is limited to the periphery of the sites. A major problem throughout seems to be related to operating methods. Under the conditions found, large quantities of rainwater and runoff could be available for leachate production. Generation of leachate may not be significant at present probably because of the recent establishment of the landfills (less than 5 years). Monitoring at these or similar sites in Puerto Rico can be limited to defining present baseline water-quality conditions and implementation of a sampling program. Baseline data could be limited to specific conductance, pH, color, common ions, and dissolved oxygen. A scheduled sampling program could be limited to specific conductance readings and measurement of concentration of bicarbonate, chloride, and dissolved oxygen.

Puerto Rico↗