Publications

In February 2010, the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, Memphis District, investigated the presence of inorganic elements and organic compounds in bed sediments of the lower Mississippi River. Selected sites were located in the navigation channel near river miles 737, 773, and 790 near Memphis, Tennessee. Bed-sediment samples were collected using a Shipe

Biotic indices for algae, macroinvertebrates, and fish assemblages can be effective for monitoring stream enrichment, but little is known regarding the value of the three assemblages for detecting perturbance as a consequence of low-level nutrient enrichment. In the summer of 2006, we collected nutrient and biotic samples from 30 wadeable Ozark streams that spanned a nutrient-concentration gradien

Eocene-age sand beds near the base of the Cockfield Formation of Claiborne Group constitute the aquifer known locally as the Cockfield aquifer. Upper-Paleocene age sand beds within the lower parts of the Wilcox Group constitute the aquifer known locally as the Wilcox aquifer. In 2005, reported water withdrawals from the Cockfield aquifer in Arkansas totaled 16.1 million gallons per day, while repo

The Nacatoch Sand and Tokio Formation aquifers in southwestern Arkansas and the Nacatoch Sand in northeastern Arkansas are sources of water for industrial, public supply, domestic, and agricultural uses. Potentiometric-surface maps were constructed from water-level measurements made in 61 wells completed in the Nacatoch Sand and in 50 wells completed in the Tokio Formation during spring 2008. Aqui

Methods of estimating flood magnitudes for exceedance probabilities of 50, 20, 10, 4, 2, 1, 0.5, and 0.2 percent have been developed for urban streams in Alabama that are not significantly affected by dams, flood detention structures, hurricane storm surge, or substantial tidal fluctuations. Regression relations were developed using generalized least-squares regression techniques to estimate flood

Public water-supply systems in Tennessee provide water to for domestic, industrial, and commercial uses, and municipal services. In 2005, more than 569 public water-supply systems distributed about 920 million gallons per day (Mgal/d) of non-purchased surface water and groundwater to a population of nearly 6 million in Tennessee. Surface-water sources provided 64 percent (about 591 Mgal/d) of the

Temporal patterns of suspended-sediment concentration (SSC) duration and frequency (SSC regimes) were characterized and compared with biological impairment thresholds for two headwater streams in the Western Highland Rim of Tennessee. The SSC regimes were plotted as curves showing concentrations and durations of the annual longest and tenth-longest SSC excursions above 18 concentrations for water

Equations have been defined for estimating the depth of water for floods having a 67-, 50-, 20-, 10-, 4-, 2-, and 1-percent chance exceedance on rural streams in Alabama. Multiple regression analyses of streamgage data were used to define the equations. Eight basin and climatic characteristics that were computed by using a geographical information system were evaluated as independent variables to

Streamflow-characteristic estimation methods for unregulated rivers and streams of Tennessee were developed by the U.S. Geological Survey in cooperation with the Tennessee Department of Environment and Conservation. Streamflow estimates are provided for 1,224 stream sites. Streamflow characteristics include the 7-consecutive-day, 10-year recurrence-interval low flow, the 30-consecutive-day, 5-year

Ouachita Parish, located in north-central Louisiana, contains fresh groundwater and surface-water resources. In 2005, about 152 million gallons per day (Mgal/d) were withdrawn from water sources in Ouachita Parish. About 84 percent (128 Mgal/d) was withdrawn from surface water, and 16 percent (24 Mgal/d) was withdrawn from groundwater. Power generation (87 Mgal/d) accounted for 58 percent of the t

St. Tammany Parish, located in southeastern Louisiana, contains fresh groundwater and surface-water resources. In 2005, about 22.8 million gallons per day (Mgal/d) were withdrawn from water sources in St. Tammany Parish. Almost 100 percent (22.7 Mgal/d) was withdrawn from groundwater, and less than 1 percent (0.06 Mgal/d) was withdrawn from surface water. Withdrawals for public supplies accounted

Ascension Parish, located along the banks of the Mississippi River in south-central Louisiana, contains fresh groundwater and surface-water resources. In 2005, about 202 million gallons per day (Mgal/d) were withdrawn from water sources in Ascension Parish. About 94 percent (190 Mgal/d) was withdrawn from surface water, and 6 percent (12 Mgal/d) was withdrawn from groundwater. Additional water is