Beginning in 1999, the U.S. Geological Survey National Water Quality Assessment Program investigated the effects of urban development on stream ecosystems in nine metropolitan study areas across the United States. In seven of these study areas, stream-che
Beaulieu, Karen M. kmbeauli@usgs.gov,Bell, Amanda H. ahbell@usgs.gov,Coles, James F. jcoles@usgs.gov. Variability in stream chemistry in relation to urban development and biological condition in seven metropolitan areas of the United States, 1999-2004. 2012-01-01.