This layer displays the locations of regulated facilities that discharge pollutants into surface waters in the United States. Location and environmental characteristics about facilities requiring discharge permits is contained in the Environmental Protection Agency (EPA) National Pollutant Discharge Elimination System (NPDES). Facilities requiring permits include industrial, municipal, and other facilities must obtain permits if their discharges go directly to surface waters (via discrete conveyances such as pipes or man-made ditches). Individual homes that are connected to a municipal system are not reported to the EPA. For more information, please visit the EPA National Pollutant Discharge Elimination System web page.