The County Watershed Program's (CWP) current Municipal Regional Permit No.CAS612008 under the National Pollutant Discharge Elimination System (NPDES) Program was enacted by the San Francisco Bay Regional Water Quality Control Board (SFBRWQCB) in December 2009. 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. 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.