Municipal Separate Storm Sewer System Area

This 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.
Organization: District of Columbia
Organization URL: https://catalog.data.gov/organization/district-of-columbia
Last updated: 2026-02-06T00:00:00.000Z
Tags: Environment, MS4, Municipal Separate Storm Sewer, drainage areas, rain, sewersheds, storm