Publications

The results of potential-scour assessments at 130 bridges and estimates of maximum scour at 10 bridges in Iowa are presented. All of the bridges evaluated in the study are constructed bridges (not culverts) that are sites of active or discontinued streamflow-gaging stations and peak-stage measurement sites. The period of the study was from October 1991 to September 1994. The potential-scour assess

The U.S. Geological Survey's investigations of the water resources of Texas are conducted in cooperation with the Texas Water Development Board, river authorities, cities, counties, U.S. Army Corps of Engineers, Bureau of Reclamation, International Boundary and Water Commission, and others. Investigations are under the general direction of R.O. Hawkinson, District Chief, Texas District. The addres

The Edwards aquifer, which is the sole source of water for the city of San Antonio, is one of the most permeable and productive carbonate aquifers in the United States. The aquifer is composed of extensively faulted, fractured, and cavernous limestone and dolomite of Early Cretaceous age lying within the Balcones fault zone a series of normal en echelon strike faults that separate the Edwards Plat

The U.S. Geological Survey, in cooperation with the Susquehanna River Basin Commission and the Pennsylvania Department of Environmental Resources, conducted a study as part of the U.S. Environmental Protection Agency's Chesapeake Bay Program to determine the effects of nutrient management of surface-water quality by reducing animal units in a 0.43-square-mile agricultural watershed in York County.

The total amount of water withdrawn in Illinois during 1988 was about 18,756 million gallons per day (Mgal/d). About 1,170 Mgal/d, or 37 percent, of the total water withdrawn in Illinois, excluding withdrawals for thermoelectric-power generation, was ground water; about 1,998 Mgal/d of surface water was withdrawn and used, excluding withdrawals for thermoelectric-power generation. About 25 Mgal/d

Rainfall and streamflow data were collected at 23 gaging stations located in urban watersheds in South Carolina from 1983-90. The site selection process and the instrumentation used to collect the data are described. A compilation of rainfall and streamflow data in graphic and tabular form for seven selected events at each gaging station are presented. A gaging-station description and a listing of

Contaminants were measured in the Mississippi River and some of its tributaries between Minneapolis, Minnesota, and the Gulf of Mexico on 10 separate occasions between July 1987 and May 1992. Measurements included contaminants dissolved in the river waters, those adsorbed on sediment particles being transported by the rivers, and contaminants stored in bottom sediments. Data from this study provid

A consistent, basin-wide set of data for streams in the Trinity River Basin is necessary to provide a baseline for current conditions, to compare with historical data, and to provide a reference for future studies by the National Water-Quality Assessment (NAWQA) Program. In addition, the basin-wide surveys begin the process of addressing the cause-effect relation for water quality in the basin. Ef

Urban storm water runoff is being investigated as a nonpoint source of pollution across the country as urban areas with populations over 100,000 conduct studies designed to meet U.S. Environmental Protection Agency guidelines for National Pollutant Discharge Elimination System permits for their stormwater discharges. From 1991 through 1994, the City of Davenport, Iowa (fig. 1), and the U.S. Geolog

No abstract available.

One water-quality monitoring site was established on Whites Bayou, at the downstream end of the study area. Sampling began in March 1994 and will continue for 1 year. Sampling frequency ranges from four times per month in May and June to once per month in July. Stream-stage measurements were made three times per week from April to September. Field measurements during sampling include stream stage

The Trinity River Basin study-unit assessment began in October 1991, with 2 years dedicated to planning, analyzing existing information, and designing data-collection networks, surveys, and studies. Then, a 3-year intensive data-collection program was initiated. The assessment followed guidelines provided by the National Water-Quality Assessment (NAWQA) Program National Synthesis team and consider