The National Hydrography Dataset is the culmination of recent cooperative efforts of the U.S. Environmental Protection Agency (EPA) and U.S. Geological Survey (USGS). It combines the best of the EPA Reach File Version 3.0 (RF3) and USGS Digital Line Graph (DLG) hydrography files. NHD is a comprehensive set of digital spatial data that contains information about surface water features such as lakes, ponds, streams, rivers, springs and wells.
This web site provides information about technical references, tools, applications, tutorial series, etc.
