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Scientific Investigations Report 2012–5225

National Water-Quality Assessment Program

Century-Scale Perspective on Water Quality in Selected River Basins of the Conterminous United States

By Edward G. Stets, Valerie J. Kelly, Whitney P. Broussard, III, Thor E. Smith, and Charles G. Crawford

Thumbnail of and link to report PDF (34.3 MB)Abstract

Nutrient pollution in the form of excess nitrogen and phosphorus inputs is a well-known cause of water-quality degradation that has affected water bodies across the Nation throughout the 20th century. The recognition of excess nutrients as pollution developed later than the recognition of other water-quality problems, such as waterborne illness, industrial pollution, and organic wastes. Nevertheless, long-term analysis of nutrient pollution is fundamental to our understanding of the current magnitude of the problem, as well the origins and the effects. This report describes the century-scale changes in water quality across a range streams in order to place current water-quality concerns in historical context and presents this history on a national scale as well as for selected river reaches. The primary focus is on nutrient pollution, but the development and societal responses to other water-quality problems also are considered. Land use and agriculture in the selected river reaches also are analyzed to consider how these factors may relate to nutrient pollution. Finally, the availability of relevant nutrient and inorganic carbon data are presented for the selected river reaches. Sources of these data included Federal agencies, State-level reports, municipal public works facilities, public health surveys, and sanitary surveys. The availability of these data extends back more than a century for most of the selected river reaches and suggests that there is a tremendous opportunity to document the development of nutrient pollution in these river reaches.

First posted November 7, 2012

For additional information contact:
Chief, National Water-Quality Assessment Program
U.S. Geological Survey
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12201 Sunrise Valley Drive
Reston, Virginia 20192

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Suggested citation:

Stets, E.G., Kelly, V.J., Broussad, W.P., III, Smith, T.E., and Crawford, C.G., 2012, Century-scale perspective on water quality in selected river basins of the conterminous United States: U.S. Geological Survey Scientific Investigations Report 2012–5225, 108 p.





Recent Ancillary Data for all Basins

Specific Basins of Interest


References Cited

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