In 2002, the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS) implemented Source Water-Quality Assessments (SWQAs) to characterize the quality of selected rivers and aquifers used as a source of supply to community water systems in the United States. These assessments are intended to complement drinking-water monitoring required by Federal, State, and local programs, which focus primarily on post-treatment compliance monitoring.
Additional publication details
USGS Numbered Series
National Water-Quality Assessment Program - Source Water-Quality Assessments