MS4 stands for Municipal Separate Storm Sewer System.
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. In December 2002, DEP issued a General Permit (“PAG-13”) for use by MS4s that fall under the National Pollutant Discharge Elimination System (NPDES) Phase II program, requiring the implementation of a stormwater management program for minimizing the impacts from runoff.
The intent of the MS4 program is to reduce pollutants into waters of the commonwealth. The program is regulated by both the Environmental Protection Agency (EPA) and the Pennsylvania Department of Environmental Protection (DEP).
Federal Regulation requires a permit for our community. The Pennsylvania Department of Environmental Protection created a state permitting program to meet federal regulations.
Lower Allen Township acquires a National Pollutant Discharge Elimination System (NPDES) permit that covers a 5-year period. The permit requires us to measure our efforts to reduce pollutants in 6 different areas, referred to as minimum control measures (MCMs). The MCMs must be reevaluated annually to determine compliance.
Sheepford Crossing West Bioretention Retrofit Project
6 Minimum Control Measures
Minimum Control Measures
Each MCM has several suggested Best Management Practices (BMPs) associated with it to guide Lower Allen Township in program development, tracking, and reporting.