USGS National Water-Quality Assessment (NAWQA)
The U.S. Geological Survey (USGS) National Water Quality Assessment Program (NAWQA) monitors water quality conditions in study units across the nation and stores all collected chemical and physical water quality data in the NAWQA Data Warehouse. The NAWQA Data Export provides an easy way to access data stored in the NAWQA Data Warehouse through form-based workbook queries as well as through standalone web services.
The link address is: http://cida.usgs.gov/nawqa_queries_public/