Regulatory Requirements

Stormwater Permits

The County Watershed Program's (CWP) current Municipal Regional Permit (MRP) No.CAS612008 (PDF) under the National Pollutant Discharge Elimination System (NPDES) Program was reissued by the San Francisco Bay Regional Water Quality Control Board (SFBRWQCB) in 2015 and amended in 2019. The MRP governs stormwater and non-stormwater discharges from areas owned and operated by Contra Costa County.

The MRP is intended to collectively address urban runoff from Phase I municipalities that discharge into the San Francisco Bay including the cities of Fairfield-Suisun and Vallejo and counties of Contra Costa, Alameda, Santa Clara and San Mateo.

Additionally, On Sept 23, 2010, the Central Valley Regional Water Quality Control Board (CVRWQB) adopted the East Contra Costa County Municipal Stormwater Permit (PDF). This permit applies to unincorporated areas in east Contra Costa County (roughly east of Pittsburg) as well as the municipalities of Antioch, Oakley, and Brentwood. The permit requirements apply to the communities of Byron, Knightsen, Bethel Island, Discovery Bay and are roughly equivalent to the requirements set forth in the MRP. See below map for the two different permit regions.

Map of Regional Water Quality Control Board Region 2 and Region 5 in Contra Costa County


The MRP contains a comprehensive plan to reduce the discharge of pollutants in stormwater to the "Maximum Extent Practicable" (MEP) in order to protect water quality. To accomplish this, the Permits are comprised of the following provisions:

  • (C.2) Municipal Operations
  • (C.3) New Development and Redevelopment
  • (C.4) Industrial and Commercial Site Controls
  • (C.5) Illicit Discharge Detection and Elimination
  • (C.6) Construction Site Control
  • (C.7) Public Information and Outreach
  • (C.8) Water Quality Monitoring
  • (C.9) Pesticides Toxicity Control
  • (C.10) Trash Load Reduction
  • (C.11) Mercury Controls
  • (C.12) Polychlorinated Biphenyls (PCBs) Controls
  • (C.13) Copper Controls
  • (C.15) Exempted and Conditionally Exempted Discharges