Gregory E Schwarz (Former Employee)

An increase in the flux of nitrogen from the Mississippi river during the latter half of the twentieth century has caused eutrophication and chronic seasonal hypoxia in the shallow waters of the Louisiana shelf in the northern Gulf of Mexico. This has led to reductions in species diversity, mortality of benthic communities and stress in fishery resources. There is evidence for a...

A greenhouse warming would have major effects on water supplies and demands. A framework for examining the socioeconomic impacts associated with changes in the long-term availability of water is developed and applied to the hydrologic implications of the Canadian and British Hadley2 general circulation models (GCMs) for the 18 water resource regions in the conterminous United States. The...

We describe a method for using spatially referenced regressions of contaminant transport on watershed attributes (SPARROW) in regional water-quality assessment. The method is designed to reduce the problems of data interpretation caused by sparse sampling, network bias, and basin heterogeneity. The regression equation relates measured transport rates in streams to spatially referenced...

Estimates of future water demand were determined for selected water-service areas in the upper Duck River basin in central Tennessee through the year 2050. The Duck River is the principal source of publicly-supplied water in the study area providing a total of 15.6 million gallons per day (Mgal/d) in 1993 to the cities of Columbia, Lewisburg, Shelbyville, part of southern Williamson...

USSOILS is an Arc 7.0 coverage containing hydrology-relevant information for 10,498 map units covering the entire conterminous United States. The coverage was compiled from individual State coverages contained in the October 1994 State Soil Geographic (STATSGO) Data Base produced on CD-ROM. The geo-dataset USSOILS.PAT relates (on the basis of a map unit identifier) the 10,498 map units...

No abstract available.

We present a statistical model relating measurements of water quality to associated errors in laboratory methods. Estimation of the model allows us to correct trends in water quality for long-term and short-term variations in laboratory measurement errors. An illustration of the bias correction method for a large national set of stream water quality and quality assurance data shows that...

This paper analyzes the determination of pollution control from wastewater treatment plants as an economic decision facing local or regional regulators. Pollution control is measured by plant design effluent concentration levels and is fully endogenous in a supply- and-demand model of treatment choice. On the supply side, plant costs are a function of the design treatment level of the...