Contra Costa County Watershed Program


The County Watershed Program (CWP) administers the Municipal Regional Stormwater National Pollutant Discharge Elimination System (NPDES) Permit (MRP) for unincorporated County. CWP works with many County departments to meet the requirements. The NPDES program is mandated by the Federal Clean Water Act and administered in California by the State Water Resources Control Board and the Regional Water Quality Control Boards (RWQCBs) on behalf of the U.S. Environmental Protection Agency (USEPA).

Report Illegal Dumping and Spills!

See our Pollution Prevention webpage for information on how to report illegal dumping and spills.

Riverside Ditch, Bay Point

The NPDES program requires certain industries, construction sites, and municipalities to have a stormwater permit and implement practices to reduce pollutants that may be carried by rain into creeks and into the Delta or the Bay. The County complies with the requirements of its NPDES permit by implementing various stormwater pollution prevention activities in the unincorporated areas of Contra Costa County, including:

  • Implementing best management practices for municipal operations such as washing vehicles in a designated area that does not drain to the storm drain
  • Managing and enforcing our stormwater compliance program and Enforcement Response Plan County Watershed Program Logo with Red-winged Blackbird on Cattailsto minimize stormwater impacts
  • Requiring new development projects mitigate impacts to stormwater quality and flow rates
  • Promoting pollution prevention awareness
  • Educating and outreach to the public
  • Supporting local non-profit creek groups
  • Inspecting businesses to ensure responsible stormwater-related practices
  • Investigating and responding to illicit discharges
  • Sweeping streets to remove pollutants before they enter the storm drain system

The first consolidated San Francisco Bay MRP (MRP 1.0) was issued to municipal permittees in Contra Costa, Alameda, Santa Clara, San Mateo, and Solano Counties in RWQCB Region 2 on October 14, 2009.

An East County Permit, which applied to the Cities of Antioch, Oakley, Brentwood, eastern portions of unincorporated Contra Costa County and the Contra Costa County Flood Control District in RWQCB Region 5 was adopted on September 23, 2010.

The San Francisco Bay RWQCB reissued the MRP (MRP 2.0) in 2015 and in 2019 amended MRP 2.0 to add the cities of Antioch, Brentwood, and Oakley as Permittees.

The current version of the MRP, MRP 3.0, was issued on May 11, 2022. MRP 3.0 can be found on the San Francisco Bay RWQCB website.

CWP is also responsible for implementing certain provisions of the MRP on behalf of the  Costa County Flood Control and Water Conservation DistriContra Costa County Flood Control and Water Conservation District (FCD). The FCD is responsible for maintaining drainage areas throughout Contra Costa County.

CWP's authority is supported by the Contra Costa County Ordinance, Title 10 Division 1014 - Stormwater Management and Discharge Control (PDF).

Contact Us

  1. 255 Glacier Drive
    Martinez, CA 94553
    Phone: (925) 313-2000
    TTY: Call 711
    Fax: (925) 313-2333

    Office Hours

    Monday - Thursday
    7:00AM to 5:00PM
    7:00AM to 4:00PM
    Closed 12:00PM to 1:00PM