MS4 – Municipal Separate Storm Sewer System
Operators of large, medium and regulated small municipal separate storm sewer sytems or MS4s are required to obtain NPDES permit coverage in order to discharge pollutants into Waters of the State. These designations (large, medium, and small) are based on urbanized areas as determined by the latest census.
Large and Medium MS4s | Small MS4s | General Permit & QLPs
Outreach Resources | Contacts | Links
Large and Medium MS4s
Large and Medium MS4s must prepare and submit a permit application to address each of the following elements:
- Structural control maintenance
- Areas of significant development or redevelopment
- Roadway runoff management
- Flood control related to water quality issues
- Municipal owned operations such as landfills, wastewater treatment plants, etc
- Hazardous waste treatment, storage or disposal sites, etc
- Application of pesticides, herbicides, and fertilizers
- Illicit discharge detection and elimination
- Regulation of sites as classified as associated with industrial activity
- Construction and post-construction site runoff control
- Public education and outreach.
South Carolina has one (1) large MS4 – the South Carolina Department of Transportion and four (4) medium MS4s – City of Columbia, Greenville County, Lexington County, and Richland County.
These MS4s receive individual NPDES permits for their discharges.
Regulated Small MS4s
Regulated Small MS4s must develop a program to cover each of the following minimum control measures:
- Public education and outreach
- Public particpation/ involvement
- Illicit discharge detection and elimination
- Construction site runoff control
- Post-construction site runoff control
- Pollution prevention/ good housekeeping.
South Carolina has 70 regulated small MS4s. The operators of these may choose to receive coverage under a general permit or obtain individual permit coverage.
Information
- NPDES General Permit for Storm Water Discharges from Regulated Small Municipal Storm Sewer Systems (MS4s) (Effective 03/06)
- DHEC Memo Concerning QLP
- DHEC Fact Sheet Concerning QLP
Contacts
Arturo Ovalles (803-898-4178)
Rick Nuzum, P.E. (803-898-4034)
Jill Stewart, P.E. (803-898-0439) , Section Manager
Victoria Kramer (803-898-4211), NPS Outreach Assistance Coordinator
Links
Clemson University
U. S. Environmental Protection Agency
Municipal Association of South Carolina
South Carolina Association of Stormwater Managers (SCASM)