Publications

A 3-year study to determine the groundwater potential of confined glacial aquifers in a large part of Allen County, Ind., was begun in July 1974 by the U.S. Geological Survey. Mapping of outwash sands and gravels delineated two distinct layers of sand and gravel in the southern and eastern parts of the county that merge into one aquifer more than 100 feet thick to the north and west. A digital mod

Three lakes in Dakota County were sampled five times during an 18-month period to determine baseline water quality prior to construction of an interstate highway. Results of physical measurements and chemical analyses showed that the lakes were shallow, nonstratified, and nutrient enriched. Considerable seasonal variations in dissolved solids, nutrient, and dissolved-oxygen concentrations were obs

Sediments of Cretaceous to Holocene age compose the Northern Atlantic Coastal Plain aquifer system in an area of 50,000 square miles in parts of New York, New Jersey, Delaware, Maryland, Virginia, and North Carolina. The aquifer system is a major source of water supply in the area. About 1.4 billion gallons is withdrawn from its aquifers each day. Increasing withdrawal of ground water has created

Cedar Lake, a kettle lake with no surface inlet or outlet, was studied to evaluate the feasibility of maintaining water levels of lakes in the glaciated kettle moraine area of eastern Wisconsin by pumping ground water into them. The general hydrogeology of the area around the lake was defined and the hydrology of the lake was studied in detail. There are two aquifer systems in the Cedar Lake area,

The model developed in this study simulates .recharge to, flow through, and discharge from the water-table aquifer in the upper Pickering Creek basin, a 5.98-square-mile basin representative of most of Chester County, Pennsylvania. The two-dimensional finite-difference model of Trescott, Pinder, and Larson was used with slight modification. The way ground-water evapotranspiration varies with depth

The Potomac-Raritan-Magothy aquifer system of Cretaceous age, which is the principal source of water to the major population and industrial centers in the Coastal Plain of New Jersey, has undergone continuous and widespread reduction in head. The reduced head, already below sea level throughout most of the aquifer system, in conjunction with encroachment of salty water toward centers of pumping, t

A technique for estimating the magnitude and frequency of floods in the Houston, Texas, metropolitan area was developed by use of a multiple-regression flood-frequency analysis of flow data from unregulated streams in the area. A regression model, relating flood-peak discharge to concurrent rainfall and antecedent soil moisture conditions, was used to simulate 67-year records of annual peak discha

The U.S. Geological Survey is conducting a study of the Cambrian and Ordovician aquifer system of the northern Midwest as part of a national series of Regional Aquifer-Systems Analysis (RASA). An integral part of this study will be a simulation of the ground-water flow regime using the Geological Survey's three-dimensional finite-difference model. The first step in the modeling effort is the desig

Nitrogen in the unsaturated soil zone in the Highland-East Highlands area of San Bernardino County, Calif., has been suspected as the source of nitrate in water from wells. Plans to recharge the local aquifers with imported surface water would raise the water table and intercept that nitrogen. This study was made to describe the distribution of inorganic nitrogen and other chemical constituents an

The volume and areal distribution of ground-water withdrawals (pumpage) for irrigation during 1980 are required for the High Plains Regional Aquifer-System Analysis. In 1979, approaches and instrumentation that might be suitable for application to 1980 water-use determinations were tested. Pumpage was sampled by monitoring time of operation and discharge of irrigation wells during the growing seas

A water-quality study of the Neuse River, N.C., based on data collected during 1956-77 at the U.S. Geological Survey stations at Clayton and Kinston, employs statistical trend analysis techniques that provide a framework for river quality assessment. Overall, water-quality of the Neuse River is satisfactory for most uses. At Clayton, fecal coliform bacteria and nutrient levels are high, but algae

A program of water-quality sampling to define the relationships between land use, watershed characteristics, and the quantity, quality, and timing of runoff has been started for the Twin Cities metropolitan area of Minnesota. Ten major watersheds were chosen as representative of conditions in the metropolitan area. Each will be sampled at one location near the outlet. Six of the watersheds are agr