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Analysis and interpretation of water-quality trends in major U.S. rivers, 1974-81

January 1, 1994

Water-quality records from two nationwide sampling networks are now of sufficient length to permit nationally consistent analysis of long-term water-quality trends at more than 300 locations on major U.S. rivers. Observed trends in 24 water-quality measures for the period 1974--81 provide evidence of both improvement and deterioration in stream quality during a time of major changes in atmospheric and terrestrial influences on surface waters. Particularly noteworthy are widespread decreases in lead and fecal bacteria concentrations and widespread increases in nitrate, arsenic, and cadmium concentrations. Changes in municipal waste treatment, leaded-gasoline consumption, highway-salt use, and nitrogen-fertilizer application, and regionally variable trends in coal production and combustion during the period, appear to be reflected in water-quality changes. There is evidence that atmospheric deposition of a variety of substances has played a surprisingly large role in water-quality changes.

Citation Information

Publication Year 1987
Title Analysis and interpretation of water-quality trends in major U.S. rivers, 1974-81
DOI 10.3133/wsp2307
Authors Richard A. Smith, Richard B. Alexander, M. Gordon Wolman
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Water Supply Paper
Series Number 2307
Index ID wsp2307
Record Source USGS Publications Warehouse
USGS Organization

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