Municipal Separate Storm Sewer System (MS4)


Stormwater runoff is generated when precipitation from rain and snowmelt events flows over land or impervious surfaces and does not percolate into the ground. As the runoff flows over the land or impervious surfaces (paved streets, parking lots, and building rooftops), it accumulates debris, chemicals, sediment or other pollutants that could adversely affect water quality if the runoff is discharged untreated. The primary method to control stormwater discharges is the use of best management practices (BMPs). In addition, most stormwater discharges are considered point sources and require coverage under an NPDES permit.

Small Municipal Separate Storm Sewer System (MS4)

Federal regulations that were issued by the United States Environmental Protection Agency (EPA) established permit requirements within the National Pollutant Discharge Elimination System (NPDES) for discharge to surface water from certain MS4s. The intent of these regulations is to improve water quality of the waterways in the United States. The permit requirement applies to small MS4s that have been designated by Pennsylvania Department of Environmental Protection (PEDEP). The Borough of Emmaus has been designated by the PADEP as one of these small MS4s.

Stormwater Management Ordinance

Under the MS4 Program, the Borough of Emmaus is required to adopt, implement, and enforce a Stormwater Management Ordinance.

The Borough of Emmaus NPDES Permit Number is "PAl132226".

View the Stormwater Management Ordinance.

Minimum Control Measures

Under the MS4 Stormwater Management Program, the PADEP established six Minimum Control Measures:

  1. Public Education and Outreach
  2. Public Participation/Involvement
  3. Illicit Discharge Detection and Elimination
  4. Construction Site Runoff
  5. Post-Construction Runoff Control
  6. Pollution Prevention/Good Housekeeping