Publications

The hydrogeologic subdivisions of the Edwards aquifer outcrop in the Medina Lake area in Medina and Bandera Counties generally are porous and permeable. The most porous and permeable appear to be hydrogeologic subdivision VI, the Kirschberg evaporite member of the Kainer Formation; and hydrogeologic subdivision III, the leached and collapsed members, undivided, of the Person Formation...

Slug tests were used to characterize hydraulic conductivity variations at a spatial scale on the order of meters in the alluvial aquifer downgradient of the Norman Landfill. Forty hydraulic conductivity measurements were made, most along a 215-meter flow path transect. Measured hydraulic conductivity, excluding clayey layers, ranged from 8.4 x 10-7 to 2.8 x 10-4 meters per second, with a...

Simple and reliable methods for estimating hourly streamflow are needed for the calibration and verification of a Chattahoochee River basin model between Buford Dam and Franklin, Ga. The river basin model is being developed by Georgia Department of Natural Resources, Environmental Protection Division, as part of their Chattahoochee River Modeling Project. Concurrent streamflow data...

The Nepalese government and some 225 families in the private sector are engaged in an expanding aquaculture program in lakes Phewa, Begnas and Rupa in the Pokhara Valley, Nepal (Swar & Pradhan 1992). Bighead carp (Aristichthys nobilis) and silver carp (Hypopthalmichthys molitrix) are propagated in hatchery ponds and are raised to market size in mesh enclosures (having sides, tops and...

Central California, in the vicinity of San Francisco and Monterey Bays, has a history of fatal and damaging landslides, triggered by heavy rainfall, coastal and stream erosion, construction activity, and earthquakes. The great 1906 San Francisco earthquake (MS=8.2-8.3) generated more than 10,000 landslides throughout an area of 32,000 km2; these landslides killed at least 11 people and...

Statistical analyses were made of selected water-quality properties and constituents for Lake Travis, northwest of Austin in central Texas. Objectives for the evaluation were: (1) to provide information on levels of selected water-quality properties or constituents to use as reference values for assessing the future effectiveness of the Lake Travis Nonpoint-Source Control ordinance of...

This publication, Environmental Toxicology and Risk Assessment: Seventh Volume, contains papers presented at the Seventh Symposium on Toxicology and Risk Assessment: Ultraviolet Radiation and the Environment, held 7-9 April, 1997 in St. Louis, MO. The symposium, the 24th in a series on environmental toxicology, was sponsored by Committee E-47. Edward E. Little, of the U.S. Geological...

Catahoula Lake, central Louisiana, is a RAMSAR Convention Wetland of International Importance and among the most important wintering and staging areas for waterfowl in North America. To evaluate exposure rates in Catahoula Lake waterfowl 5 years after a ban on use of lead shot, we determined the prevalence of ingested shot and diets of canvasbacks (Aythya valisineria) and lesser scaup (A...

Approximately 170 Mgal/d (million gallons per day) of ground- and surface-water was withdrawn from the Barataria-Terrebonne Basins in 1995. Of this amount, surface water accounted for 64 percent ( 110 MgaVd) of the total withdrawal rates in the basins. The largest surface-water withdrawal rates were from Bayou Lafourche ( 40 Mgal/d), Bayou Boeuf ( 14 MgaVd), and the Gulf Intracoastal...

No abstract available

The natural establishment of woody seedlings on abandoned agricultural fields was investigated at sites in Louisiana and Mississippi. Series of disked and undisked plots originating at forest edges and oriented in cardinal directions were established on fields at each site. During the firest 2 years, seedling recruitment was dominated by sweetgum, sugarberry, and elms at both sites...

Clear-water contraction and abutment scour data were collected at 128 bridge sites in South Carolina. In the sandy soils of the Coastal Plain, clear-water-scour data were collected at 63 sites (scour depths ranged from 0.4 to 7.2 meters.) In the clayey soils of the Piedmont, clear-water-scour data were collected at 47 sites (scour depths ranged from 0 to 1.4 meters.) In the sandy, clayey...