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O. J. Cosner

Publications and source records attributed to O. J. Cosner.

6 recordsLinked to original sources
USGS1978

Digital-model simulation of the glacial-outwash aquifer, Otter Creek-Dry Creek basin, Cortland County, New York

The city of Cortland, New York, and surrounding areas obtain water from the highly productive glacial-outwash aquifer underlying the Otter Creek-Dry Creek basin. Pumpage from the aquifer in 1976 was approximately 6.3 million gallons per day and is expected to increase as a result of population growth and urbanization. A digital ground-water model that uses a finite-difference approximation technique to solve partial differential equations of flow through a porous medium was used to simulate the movement of water within the aquifer. The model was calibrated to equilibrium conditions by comparing water levels measured in the aquifer in March 1976 with those computed by the model. Then, from the simulated water-level surface for March, a transient-condition run was made to simulate the surface as measured in September 1976. Computed water levels presented as contours are generally in close agreement with potentiometric-surface maps prepared from field measurements of March and September 1976.

New York↗
USGS1976

Measured and simulated ground-water levels in the Franklin area, southeastern Virginia

The Lower Cretaceous aquifer is the principal source of water in Southeastern Virginia. Synoptic water-level measurements made since 1970 have been used to verify a digital model of the aquifer. Measurements made in December 1973, August and December 1974 were used to further verify the model, using updated pumpage for those periods. The close agreement of the potentiometric maps based on measured and simulated water levels indicates that the model is simulating hydrologic conditions satisfactorily. (Woodard-USGS)

Virginia↗
USGS1975

A predictive computer model of the Lower Cretaceous aquifer, Franklin area, southeastern Virginia

The Lower Cretaceous aquifer of Southeastern Virginia is simulated in this study. The aquifer is only a few feet thick along the Fall Line, where it is near or at the surface, but it thickens and dips to the east. At Franklin where the top of the aquifer is 220 feet (67 metres) below sea level, it is about 600 feet (180 metres) thick. Thirty five miles (56 kilometres) east of Franklin, along the eastern boundary of the model area, the top is about 900 feet (270 metres) below sea level, and the thickness is estimated to be 2,000 feet (610 metres). The aquifer consists of an alternating series of permeable and semipermeable beds, which contain various mixtures of sand, gravel, silt and clay. The sediments are continental stream deposits in the western and central parts of the area, but grade to marine deposits in the eastern part. Transmissivity is zero at or near the Fall Line, and increases eastward to 19,000 cubic feet per day per foot (1,800 cubic metres per day per metre) at Franklin. Further eastward, trans-missivity probably increases slightly, but then decreases as the marine phase is reached. The aquifer is.overlain by a semiper-meable'confining layer and is underlain by relatively impermeable rocks of the pre-Cretaceous basement. The model used is the finite-difference digital type described by Pinder (1970). Historical water levels of the aquifer were simulated from 1891 to December 1, 1972. The 1891 water-level surface was developed by running a steady-state version of the Pinder model. Simulation runs from 1891 to 1941, 1970, and 1972 are in good agreement with historical water levels. A modeling factor was used as a multiplier for varying the coefficients of transmissivity and vertical permeability of the confining layer without altering the initial (1891) surface used to start the modeling runs. This technique should be helpful in the development of other models of artesian aquifers. Predicitive runs show that, if pumpage continues to increase as it has in the past, serious dewatering of the aquifer will occur at Franklin and possibly at other centers of increased pumpage. However, a predictive run to the year 2022 shows that if pumpage does not increase, additional drawdown would be small. Other predictive runs show the effects caused by hypothetical withdrawals at other locations.

Virginia↗
USGS1972

Water in St. John, U.S. Virgin Islands

Water for domestic and municipal supply on St. John, in the past, has been obtained from rain catchments, dug wells, and barge shipments from St. Thomas and Puerto Rico. As a result of this study, small ground-water supplies have been developed for the Virgin Islands National Park. Ground water occurs in significant but limited quantities in the fractured volcanic rock throughout most of the Island. Yield of wells in this aquifer ranges from less than 100 to about 2,000 gpd (gallons per day). The average long-term yield of the three drilled wells in use by the National Park Service in 1967 was about 1,000 gpd. Yield ofl,000 to 5,000 gpd may be expected in the Coral Bay and the Reef Bay areas. Estimated total recharge of the fractured volcanic rock on St. John, based on a recharge of 1 to 3 inches per year, is 1,000,000 to 3,000,000 gpd. Perhaps as much as a quarter to a third of this water could be developed practically, depending on the rainfall in a given year. The chemical quality of the ground water in the fractured-rock aquifer in areas uncontaminated by sea water ranges from 600 to 2,000 mg/l (milligrams per liter) or more dissolved solids. Water from-formations in the higher altitudes is of better quality than that in the lower formations. Small quantities of ground water are available from beach sand, alluvium, and fractured rock near the sea. However, these sources tend to be brackish and are subject to salt-water encroachment. There are no perennial streams on St. John. There are a few spring-fed pools in stream channels, however, that are sustained, except in severe drought. Storm runoff is estimated to average 1 inch over the island annually, and evaporation from open water surfaces is about 70 inches per year. Ponds can be developed, but because of the high .evaporation they may be unreliable during droughts. Rain water collected in cisterns from roofs and catchments yield about 50 gpd per 1,000 square feet of catch area during an average year of rainfall. This is the main method of Water supply for domestic use on the Island; it will probably be continued even if a public distribution system is made available, because of the limited quantity of other natural water.

Open-File Report↗