Hydrologic Unit Boundaries (HUC-8) in the Chesapeake Bay Watershed

Description

The U.S. Geological Survey (USGS) delineates watersheds across the United States through a system that divides the country into hydrologic units. Each hydrologic unit is assigned a number that uniquely identifies descending levels of classification using two-digit fields. An eight-digit Hydrologic Unit Code (HUC-8) consists of four, two-digit pairs that represent a region, subregion, basin, and subbasin. This map of the HUC-8 coverage for the Chesapeake Bay watershed is based on information from the USGS Watershed Boundary Dataset, clipped to the boundary of the Chesapeake Bay basin.