NC Subwatersheds (12-Digit HUC)

North Carolina subwatersheds clipped to the state boundary as of March 2026. Includes watershed and basin information, as well as estimated US Census population within each subwatershed area. HUC boundaries are from the USGS National Hydrography Watershed Boundary Dataset. US Census 2020, 2010, and 2000 Block Data was acquired through NC OneMap. Subwatershed population estimates were derived from the 2020, 2010, and 2000 Block population data from the US Census. The ArcGIS Tool "Summarize Within" was used to calculate the total population within each subwatershed for each census period. As census blocks and subwatershed boundaries do not always coincide, the calculated population is only an estimate and is not to be used as an exact figure. For all inquiries, please contact the DWR GIS Team. Attributes: Hydrologic Unit Code 12 Subwatershed Name Hydrologic Unit Code 10 Watershed Name Hydrologic Unit Code 8 Subbasin Name Hydrologic Unit Code 6 Basin Name To HUC Area in Square Miles Area in Acres Estimated 2000 Population Estimated 2010 Population Estimated 2020 Population