MS4 permittees must develop, implement, and enforce a Stormwater Management Program (SWMP) designed to reduce the discharge of pollutants from the MS4 to the maximum extent practicable, to protect water quality, and to satisfy the appropriate water quality requirements of the Clean Water Act(opens in a new tab) and Pennsylvania Clean Streams Law(opens in a new tab) (PDF).
The SWMP consists of six Minimum Control Measures (MCMs) as listed in the PAG-13 MS4 General Permit(opens in a new tab) (PDF) or MS4 Individual Permit(opens in a new tab).
- Public Education and Outreach on Stormwater Impacts
- Public Involvement/Participation
- Illicit Discharge Detection and Elimination (IDD&E)
- Construction Site Stormwater Runoff Control
- Post-Construction Stormwater Management (PCSM)
- Pollution Prevention/Good Housekeeping
Best Management Practices (BMPs) for MS4 permittees to implement are identified under each MCM.
MS4 permittees must demonstrate compliance with their SWMP through the submission of periodic reports. For the 2018 permit term, MS4 Annual Status Reports are due by September 30th each year for the preceding reporting period of July 1 – June 30.