Permittees & Permit Requirements

There are currently 122 permitted MS4 entities in North Carolina.  Some MS4s elect to cooperatively implement their stormwater management programs and are issued a single permit naming them as co-permittees.  There are currently 109 active NPDES MS4 permits:

• List of MS4 permittees
• PDF map of MS4 areas
• Interactive MS4 Map Viewer 

MS4 Tipped Areas

Development activities within the unincorporated area of a county may be subject to the MS4 Post-Construction Site Runoff Control requirements [15A NCAC 02H .1017] if the development is within a U.S. Census designated Urbanized Area or the municipal sphere of influence around an MS4 [15A NCAC 02H .1016]. Counties with urbanizing areas are called “Tipped Counties” because they are subject (or tipped in) to just the post-construction portion of the MS4 requirements, but they do not receive MS4 permits. 

In the MS4 Tipped Area, the owner/operator of the development activity is required to obtain a stormwater post-construction permit if it meets the applicability criteria in 15A NCAC 02H .1001.  Post-Construction stormwater permitting for development in these areas may be performed by either the county, local government or DEQ:

• List of Post-Construction Tipped Counties
• Post-Construction Permitting Interactive Map

Permit Requirements

DEQ issues individual NPDES MS4 Permits for a five-year permit term and does not currently offer a general permit option.  DEMLR has developed a Baseline Phase II MS4 Permit Template which provides the starting point for developing each individual MS4 permit.  Every permit includes a Stormwater Management Plan (SWMP) and requirements for annual reporting.  The SWMP contains enforceable Best Management Practices (BMPs) and measurable goals for the implementation of a comprehensive stormwater management program that complies with the permit requirements. 

The primary components of a NPDES MS4 permit include program administration, any applicable Total Maximum Daily Load (TMDL) requirements, and programs to address each of the six required Minimum Control Measures (MCMs):

• Public Education & Outreach
• Public Involvement & Participation
• Illicit Discharge Detection & Elimination
• Construction Site Runoff Controls
• Post-Construction Site Runoff Controls
• Pollution Prevention & Good Housekeeping
  • Municipal Facilities Operation and Maintenance
  • Spill Response
  • MS4 Operation and Maintenance
  • Municipal SCM Operation and Maintenance
  • Pesticide, Herbicide and Fertilizer Management
  • Vehicle and Equipment Maintenance
  • Pavement Management