Information and Links to USGS Aquatic Resource Programs

Directory of USGS web sites and information: www.usgs.gov/network/

Water Resources of the United States: water.usgs.gov

National Water-Quality Assessment (NAWQA) Program: water.usgs.gov/nawqa/

Assessing more than 50 river basins and aquifer systems
Collects and interprets data about water chemistry, hydrology, land use, stream habitat, and aquatic life
Model-based assessment, not Design-Based (Probability Based Surveys)

National Hydrography Dataset (NHD)

Comprehensive set of digital spatial data that contains information about surface water features such as lakes, ponds, streams, rivers, springs and wells.
Surface water features are combined to form "reaches," which provide the framework for linking water-related data to the NHD surface water drainage network.
Linkages enable the analysis and display of water-related data in upstream and downstream order.
Based upon the content of USGS Digital Line Graph (DLG) hydrography data integrated with reach-related information from the EPA Reach File Version 3 (RF3).
The NHD supersedes DLG and RF3 by incorporating them, not by replacing them.
Users of DLG or RF3 will find the National Hydrography Dataset both familiar and greatly expanded and refined.
NHD is still under development but data can be downloaded as soon as it has been QA/QC'd.

Availability of data for a specific area can be determined through the web site nhd.usgs.gov