NHD - Watershed Boundaries HUC 6

This dataset is a representation of Hydrologic Unit Code (HUC) boundaries at the HUC6 level compiled from U.S. Geological Survey (USGS) National Hydrography Dataset (NHD) and U.S. Department of Agricultural (USDA) National Resources Conservation Services (NRCS) Watershed Boundary Dataset (WBD) sources.The Watershed and Subwatershed hydrologic unit boundaries (WSB)provide a uniquely identified and uniform method of subdividing large drainage areas. The smaller sized 6th level sub-watersheds (up to 250,000 acres) are useful for numerous application programs supported by a variety of local, State, and Federal Agencies.