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J. F. Williams

Publications and source records attributed to J. F. Williams.

4 recordsLinked to original sources
USGS1985

Estimated public-water supply and industrial-commercial ground-water withdrawals and returns in Nassau County, Long Island, New York, 1973-79

Nassau County, New York depends upon ground water for its freshwater supply. The primary water uses are for public-water supply and industrial-commercial purposes, which together accounted for 202 Mgal/d (million gallons per day) in 1975. Public-water suppliers withdrew 85 percent of their water from the Magothy Formation. About 133 Mgal/d was returned to the ground after use in 1975, and about 69; Mgal/d was discharged to tidewater. In addition, about 34 Mgal/d infiltrated into sewerlines in 1975 and was also discharged to tidewater. Because of the importance of this freshwater supply, the New York State Department of Environmental conservation reviews applications for the installation of wells and compiles data on pumpage throughout Long Island. It also reviews applications to discharge wastewater into the surface water and ground water of the State. This report summarizes the data filed with the New York State Department of Environmental Conservation for Nassau County during 1973-79. It presents data and estimates on withdrawals for public and industrial-commercial supply, returns to the ground, and discharges through sewer systems. It also includes information on population and land use.

New York↗
USGS1982

Simulated changes in water levels in the Minjur Aquifer, Riyadh area, Saudi Arabia

A two-dimensional finite-difference computer model of the Minjur aquifer in the Riyadh area of Saudi Arabia was developed to simulate and predict drawdown in an aquifer which, in 1979, supplied more than 80 percent of all water used in this capital area. The Minjur was modeled as a confined aquifer recharged by leakage through underlying confining beds. Pumpage was simulated for a 23-year period during which it increased from 2,160 to 220 ,000 cubic meters per day. At Riyadh, the top of the Minjur aquifer is about 1200 meters below land surface. Aquifer thickness within the 40,000-square-kilometer study area ranges from 74 to 138 meters inclusively. Values for aquifer characteristics used in the model are: transmissivity, from 0.001 to 0.0062 square meters per second; storage coefficients, 0.07 for the unconfined, and 0.0004 for the confined sectors of the model area. A value of 0.02 meters per second was used to represent the vertical conductivity of the confining bed. Predictive simulations indicate that if the Minjur aquifer in the Riyadh area is stressed by estimated future pumpages, static water-level declines ranging from 10 up to and including 90 meters, depending on location, will occur from 1980 through 1999. Simulations also demonstrated that pumping levels in the new Buwayb well field will decline substantially from 1980 through 1981. (USGS)

Open-File Report↗