City of Washington, DCThis layer depicts a generalized boundary of the District's Municipal Separate Storm Sewer System (MS4) drainage areas. Each sewershed shows the general drainage area of a system of pipes and structures that carries only stormwater runoff that empty into natural or manmade surface waterways. This data is a requirement of the District's MS4 Permit. It is used for stormwater management and all aspects supporting efforts to comply with the Clean Water Act in the District. The dataset contains locations and attributes of the drainage areas of MS4 outfalls.ArcGIS DynamicMapLayerhttps://hub.arcgis.com/datasets/7b160ea881874139872285440b5d2259_0engOpen Data DCPublicMunicipal Separate Storm Sewer System Area [District of Columbia--Washington]Web servicesDistrict of Columbia--WashingtonDistrict of ColumbiaLast Modified: 2026-02-06