Municipal Separate Storm Sewer Systems (MS4)

Municipal Separate Storm Sewer Systems (MS4) are infrastructure systems designed to manage stormwater runoff in urban areas. Unlike traditional sewage systems, MS4s collect rainwater and melting snow through drains and pipes, directing it into local waterways without treatment. This helps prevent flooding and reduces pollution. MS4 programs, regulated by the Environmental Protection Agency (EPA), require municipalities to implement measures that minimize harmful runoff, protect water quality, and promote public awareness about stormwater management. Essentially, MS4s are crucial for maintaining clean, safe waterways in populated areas while addressing the challenges posed by urban development.