NAWQA Data Warehouse Home

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Data subject to change - source data extracted between 10/28/2009 and 10/30/2009.

NAWQA study units image

About the NAWQA Data Warehouse

The U.S. Geological Survey (USGS) began its NAWQA (National Water Quality Assessment) program in 1991, systematically collecting chemical, biological, and physical water quality data from 42 study units (basins) across the nation. The data warehouse currently contains and links the following data:
  • Chemical concentrations in water, bed sediment, and aquatic organism tissues for about 2,400 chemical constituents
  • Site, basin, well and network characteristics with many descriptive variables
  • Daily stream flow information for fixed sampling sites
  • Ground water levels for sampled wells
  • 7,600 surface water sites (including 3,400 reach segments for biological studies) and 9,000 wells
  • 61,000 nutrient samples and 39,000 pesticide samples as well as 11,000 VOC samples
  • 2,700 samples of bed sediment and aquatic organism tissues
  • Biological community data for 22,500 fish, algae and invertebrate samples

Most of these data came from the USGS National Water Information System--NWIS Water-Quality Data for NAWQA sites.