EPA Impaired Waters presence and causes for HUC12 watersheds across the Conterminous U.S.
This dataset summarizes impairment status for HUC12 watersheds at the CONUS scale using the EPA publicly available Assessment, Total Maximum Daily Load (TMDL) Tracking and Implementation System (ATTAINS) geospatial package and the USGS Watershed Boundary Dataset (WBD). ATTAINS is an online system maintained by the EPA …