,Every year, the District submits an Annual Municipal Separate Storm Sewer System (MS4) Report to the U.S. Environmental Protection Agency (EPA), documenting the activities that fulfill the requirements of the District’s National Pollutant Discharge Elimination System (NPDES) MS4 permit. The NPDES permit program, authorized by the federal Clean Water Act and managed by the EPA, addresses water pollution by regulating point sources that discharge pollutants to waters of the United States. Activities under the permit include, for example, implementation of stormwater management practices and water quality monitoring. This story map summarizes these activities and is a regulatory requirement under the permit.,MS4 is an acronym that stands for Municipal Separate Storm Sewer System. The MS4 collects and conveys stormwater from streets, sidewalks, and rooftops to nearby waterways through stormwater sewers and outfalls. In the District of Columbia, the MS4 area is located along the outer edges of the city and surrounds the combined sewer system (CSS) area that serves the inner portions of the city. The MS4 area is different from the CSS area in that it does not convey sanitary sewage. Stormwater from the CSS area is either conveyed to the Blue Plains Wastewater Treatment Plant or discharged at combined sewer outfalls. DC Water’s Clean Rivers Program is dedicated to reducing combined sewer overflows into the District’s waterways.,Several areas in the District are not part of either the MS4 or CSS. Most District parkland falls within this “Direct Drainage” category, and stormwater from these areas naturally drain to nearby waterways following the local topography.,Learn more about why the MS4 is important to the District's waterways in this Story Map collection.,,

,Every year, the District submits an Annual Municipal Separate Storm Sewer System (MS4) Report to the U.S. Environmental Protection Agency (EPA), documenting the activities that fulfill the requirements of the District’s National Pollutant Discharge Elimination System (NPDES) MS4 permit. The NPDES permit program, authorized by the federal Clean Water Act and managed by the EPA, addresses water pollution by regulating point sources that discharge pollutants to waters of the United States. Activities under the permit include, for example, implementation of stormwater management practices and water quality monitoring. This story map summarizes these activities and is a regulatory requirement under the permit.,MS4 is an acronym that stands for Municipal Separate Storm Sewer System. The MS4 collects and conveys stormwater from streets, sidewalks, and rooftops to nearby waterways through stormwater sewers and outfalls. In the District of Columbia, the MS4 area is located along the outer edges of the city and surrounds the combined sewer system (CSS) area that serves the inner portions of the city. The MS4 area is different from the CSS area in that it does not convey sanitary sewage. Stormwater from the CSS area is either conveyed to the Blue Plains Wastewater Treatment Plant or discharged at combined sewer outfalls. DC Water’s Clean Rivers Program is dedicated to reducing combined sewer overflows into the District’s waterways.,Several areas in the District are not part of either the MS4 or CSS. Most District parkland falls within this “Direct Drainage” category, and stormwater from these areas naturally drain to nearby waterways following the local topography.,Learn more about why the MS4 is important to the District's waterways in this Story Map collection.,,

,Every year, the District submits an Annual Municipal Separate Storm Sewer System (MS4) Report to the U.S. Environmental Protection Agency (EPA), documenting the activities that fulfill the requirements of the District’s National Pollutant Discharge Elimination System (NPDES) MS4 permit. The NPDES permit program, authorized by the federal Clean Water Act and managed by the EPA, addresses water pollution by regulating point sources that discharge pollutants to waters of the United States. Activities under the permit include, for example, implementation of stormwater management practices and water quality monitoring. This story map summarizes these activities and is a regulatory requirement under the permit.,MS4 is an acronym that stands for Municipal Separate Storm Sewer System. The MS4 collects and conveys stormwater from streets, sidewalks, and rooftops to nearby waterways through stormwater sewers and outfalls. In the District of Columbia, the MS4 area is located along the outer edges of the city and surrounds the combined sewer system (CSS) area that serves the inner portions of the city. The MS4 area is different from the CSS area in that it does not convey sanitary sewage. Stormwater from the CSS area is either conveyed to the Blue Plains Wastewater Treatment Plant or discharged at combined sewer outfalls. DC Water’s Clean Rivers Program is dedicated to reducing combined sewer overflows into the District’s waterways.,Several areas in the District are not part of either the MS4 or CSS. Most District parkland falls within this “Direct Drainage” category, and stormwater from these areas naturally drain to nearby waterways following the local topography.,Learn more about why the MS4 is important to the District's waterways in this Story Map collection.,,

The DOEE 2023 MS4 Annual Report is presented as a collection of Story Map chapters, as shown on the right. Select any chapter to learn more about that topic. Other chapters can then be accessed along the top as links. Best viewed on desktop/laptop.

Retired September 28, 2023. District MS4 Sewershed drainage areas. The dataset contains locations and attributes of the drainage areas of MS4 outfalls created as part of the DC Geographic Information System (DC GIS) for the D.C. Office of the Chief Technology Officer (OCTO) and participating D.C. government agencies. A database provided by WASA identified outfalls, drainage structures, and MS4 outfall locations. All DC GIS data is stored and exported in Maryland State Plane coordinates NAD 83 meters.

,

Most Municipal Separate Storm Sewer System (MS4) permittees in the State of Washington are a part of the Regional Stormwater Monitoring Program (RSMP). One part of the RSMP is the Source Identification Information Repository. Permittees may choose to enter their permit-required illicit discharge data into this dataset using a form, simplifying both their reporting processes and analyses for the RSMP.

,

New York City’s Municipal Separate Storm Sewer System (MS4) Stormwater Management Program is a multiagency effort led by the Department of Environmental Protection (DEP) to reduce pollution in stormwater runoff in the MS4 Area of NYC. This MS4 Map represents the known MS4 outfalls and drainage areas as of August 1, 2020 and provides additional data relevant to the MS4 Permit. The MS4 map only shows areas draining to the Municipal Separate Storm Sewer System. DEP also maintains combined sewer and sanitary sewer systems; these service area delineations are not represented on this map. More information about the MS4 Stormwater Management Program is available at www.nyc.gov/dep/ms4