Publications

Data recorded from 1973 through 1978 by monitors on West Branch Brandywine Creek at Modena, East Branch Brandywine Creek below Downingtown, and Brandywine Creek at Chadds Ford were analyzed to evaluate the effectiveness of the monitors in describing water-quality conditions. The data show that the stream at Modena and below Downingtown had periods of low dissolved oxygen, and that the stream below

This chapter contains practices used by the U.S. Geological Survey to assure the quality of analytical data for water, fluvial sediment, and aquatic organisms. These practices are directed primarily toward personnel making water quality measurements. Some detail specific quality control techniques, others document quality assurance procedures being used by the Central Laboratories System of the U.

The use of fluorescent dyes and tracing techniques provides a means for measuring the time-of-travel and dispersion characteristics of steady and gradually varied flow in streams. Measurements of the dispersion and concentration of dyes give insight into the behavior of soluble contaminants that may be introduced into a stream. This manual describes methods of measuring time of travel of wa

An investigation of water quality in the French Broad River in North Carolina has resulted in the definition of variations in water quality, a determination of the degree to which the quality of water in the river has been affected by man 's activities, and an analysis of trends in the changing chemical quality of the river. The investigation centered on data collected during 1958-77 at the U.S. G

For more than 100 years, the U.S. Geological Survey has pursued its mission of assessing and mapping the earth resources of the United States, including assessment of the Nation's water resources. Although the Survey has never been a water-management or development agency, it has assisted agencies that are responsible for such developments, and commonly provides data and information for such purpo

Interpretation of water-quality data collected by the U.S. Geological Survey for the Neuse River, North Carolina, has identified water-quality variations, charactrized the current condition of the river in reference to water-quality standards, estimated the degree of pollution caused by man, and evaluated long-term trends in concentrations of major dissolved constituents. Two sampling stations

The design and objectives of the program for evaluating stream quality in North Carolina are described. Using water-quality and streamflow data collected since the 1940?s, a study is underway to define certain variations in water quality, to quantify the effects of man?s activities on water quality, and to determine long-term trends at key locations on the State?s major rivers. Data collected from

A series of seven studies of the quality and quantity of low flows in a 35.5-mile reach of the Colorado River upstream from Colorado City, Tex., were made from February 1975 to March 1978 to delineate areas of saline inflows. These studies showed generally that ground water contributed throughout the reach is saline but that loads of dissolved-constituents in ground-water accretions are highest in

Step-backwater computations were verified by subsequent discharge measurements at three ephemeral streamflow stations in northeastern Wyoming. The standard step-backwater method for gradually varied, subcritical flow was used in computing the water-surface profiles and stage-discharge ratings. Step-backwater computations were made at selected intervals from I through 1,000 cubic feet per second on

Statistics of monthly minimum flows are presented for 129 streamflow stations for each month of the year. Flow statistics provided are the log-Pearson Type III distribution. The probable magnitude of average standard errors due to time-sampling bias is tabulated. The average standard errors were found to be similar over a wide area comprising approximately the northern two-thirds of the State. In

The U.S. Geological Survey's investigations of the water resources of Texas are conducted in cooperation with the Texas Department of Water Resources, river authorities, cities, counties, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation, International Boundary and Water Commission, and others.

Hydrologic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. Studies are now in progress in Austin, Houston, and San Antonio. Studies have been completed in the Dallas and Fort Worth areas. The Geological Survey, in cooperation with the Texas Department of Water Resources, began hydrologic studies in the Austin urban area in 1954. In cooperation with the