Municipal Separate Stormwater Sewer System (MS4)

Whitemarsh Township is one of approximately 1,000 jurisdictions in Pennsylvania that are considered small municipal separate stormwater systems (MS4s), requiring a permit from the Pennsylvania Department of Environmental Protection (PADEP).

Stormwater Requirements
The stormwater requirements of the Federal Clean Water Act are administered under the Pennsylvania Department of Environmental Protection's Municipal Separate Storm Sewer (MS4) Program. Under the MS4 Program, permittees are required to incorporate the following six elements (known as minimum control measures, or MCMs) into their stormwater management programs:
  • Public education and outreach
  • Public involvement and participation
  • Illicit discharge detection and elimination
  • Construction site runoff control
  • Post-construction stormwater management in new development and redevelopment
  • Pollution prevention and good housekeeping for municipal operations and maintenance
Each MCM has a series of suggested Best Management Practices (BMPs) associated with it to guide permit holders in program development, tracking and reporting.