The Municipal Separate Storm Sewer System (MS4) refers to a collection of structures designed to gather stormwater from municipal sources and discharge it into local streams and rivers. These structures include retention basins, ditches, roadside inlets and underground pipes.
MS4 is separate from the sanitary sewer system and private septic systems that treat household wastewater. If you are seeking information about preventing stormwater pollution on private property, please see the Conservation Department.
Stormwater Management Plan (SWMP)
Stormwater runoff is the leading cause of water pollution in New England. It may threaten drinking water or impact water quality keeping residents from safely swimming and fishing in local ponds, lakes and oceans. Each year, as part of its MS4 permit, Dedham is required to update and revise its Stormwater Management Plan to meet the requirements of our permit.
The following documents are available for download:
Year 2 SWMP: Dedham Draft SWMP - June 2020
Year 1 SWMP: Dedham Final SWMP - June 2019
Town of Dedham Annual MS4 Stormwater Reports
Stormwater discharges from municipal sources are regulated under the National Pollutant Discharge Elimination System. For more information, see Stormwater Discharges from Municipal Sources. The Town of Dedham submits to EPA an annual report detailing the Town's progress in addressing stormwater. You can download those reports below.