Regions or areas bounded by drainage divides and occupied by drainage systems; specifically the tract of country that gathers water originating as precipitation and contributes it to a particular stream channel or system of channels, or to a lake, reservoir, or other body of water. [Glossary of Geology, 4th ed.]
Summary of a circular on USGS environmental research and Chesapeake Bay with links to full document. Includes discussion of the problems of the estuary, restoration efforts, water quality, and effects on ecosystem.
Detailed information on Total Maximum Daily Load, the total quantity of a pollutant that a stream can carry and still conform to water quality standards, used as a measurement in the monitoring, assessment, and remediation of polluted waters.
Overview of project assessing water quality of the Tualatin River basin near Portland, Oregon with links to reports on chemical and nutrient levels and selected data on streamflow, water temperature, weather and precipitation.
The Sacramento-San Joaquin River Delta is the hub of California's water system and an important habitat for fish and wildlife. USGS research has provided resource managers and other stakeholders with a good understanding of how pesticides enter the Delta.
Hydrologic data web page for the Water Resources Inventory Area 1 (WRIA 1) Watershed Management Project studying surface and ground water in the Nooksack watershed in northwest Washington. Links to environmental data and maps.
Local projects of the Mississippi District Office on water resources of Mississippi including studies relating to erosion, floods, water data collection, ground water flow, Geographic Information Systems (GIS) techniques, and others.