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MS4: The Six Minimum Measures

The Environmental Protection Agency's Stormwater Phase II Rule establishes an MS4 stormwater management program that is intended to improve the nation's waterways by reducing the quantity of pollutants that stormwater carries into storm sewer systems during rain events.  Recognizing the value of approaching the new requirements regionally, the GLRC began meeting in 1998 and was officially formed under a Memorandum of Agreement in 2004.  The GLRC guides the implementation of the Phase II stormwater program by coordinating and cooperating on all program elements, known as the "six minimum control measures."

Construction Site Runoff Control:  Developing, implementing, and enforcing an erosion and sediment control program for construction activities that disturb one or more acres of land.  Controls could include silt fences and temporary stormwater detention ponds.

Post-Construction Runoff Control:  Developing, implementing, and enforcing a program to address discharges of post-construction stormwater runoff from new development and redevelopment areas. Applicable controls could include preventative actions such as protecting sensitive areas (e.g., wetlands) or the use of structural BMPs such as grassed swales or porous pavement.

Pollution Prevention/Good Housekeeping:  Developing and implementing a program with the goal of preventing or reducing pollutant runoff from municipal operations.  The program must include municipal staff training on pollution prevention measures and techniques, such as regular street sweeping, reduction in the use of pesticides or street salt, or frequent catch-basin cleaning.

Public Education and Outreach:  Distributing educational materials and performing outreach to inform citizens about the impacts polluted stormwater runoff discharges can have on water quality.

Public Participation/Involvement: Providing opportunities for citizens to participate in program development and implementation, including effectively publicizing public hearings and/or encouraging citizen representatives on a stormwater management panel.

Illicit Discharge Detection and Elimination:  Developing and implementing a plan to detect and eliminate illicit discharges to the storm sewer system.  Activities include developing a system map and informing the community about hazards associated with illegal discharges and improper disposal of waste.  

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