Evaluating Water Quality of Navigable Waters in Georgia Using a Geographic Information System

Abstract

As mandated by the Clean Water Act, the State of Georgia, Georgia Department of Natural Resources (GDNR), is required to prepare biennial reports describing current quality of the navigable waters in the State (Georgia Department of Natural Resources, 1997). The U.S. Geological Survey (USGS), in cooperation with the GDNR constructed a geographic information system (GIS) map and accompanying relational database to make water-quality data more accessible and useful to the public than in previously published table formats. Using GIS methods and techniques, GDNR attribution data first were combined to the U.S. Environmental Protection Agency River Reach files; and then combined with the USGS-Digital Raster Graphic Files to construct the current map product and database.