Central Valley Regional Water Quality Control Board
The Central Valley Region is the State's largest, encompassing 60,000 square miles, or about 40 percent of the State's total area. Thirty-eight of California's 58 counties are either completely or partially within the Regional Board's boundaries, formed by the crests of the Sierra Nevada on the east, the Coast Ranges and Klamath Mountains on the west, the Oregon border on the north, and the Tehachapi Mountains on the south. Included are 11,350 miles of streams, 579,110 acres of lakes and the largest contiguous groundwater basin in California. The Sacramento and San Joaquin Rivers, along with their tributaries, drain the major part of this large area through an inland Delta, prior to emptying into San Francisco Bay. The Delta is the focal point of the state's two largest water conveyance projects, the State Water Project and the federal Central Valley Project. Together, the Sacramento and San Joaquin Rivers and the Delta furnish over half of the state's water supply. The southern third of the Central Valley contains the Tulare Lake Basin, a closed hydrographic unit, except during extremely wet years. The Central Valley is one of the most important agricultural centers of the world. Its largest city is Sacramento, the state capital. The Regional Board's headquarters is in Sacramento with branch offices in Redding and Fresno.

In response to the many challenges it faces, the Regional Board has achieved a number of accomplishments, including:
  • Initiated watershed activities involving over 500 stakeholders for the Sacramento River and for Cache Creek
  • Working in cooperation with approximately 30 local agencies, closed over 3,100 underground tank sites; Developed "hot spot" cleanup plans to address dissolved oxygen and mercury problems in the Delta
  • Adopted the first-ever waste discharge requirements on agriculture to control selenium discharges from the Grasslands Watershed to the San Joaquin River
  • Restored and improved the regulation of confined animal facilities, especially dairies, by documenting violations, enforcing under Board authority and in coordination with a new multi-agency dairy enforcement task force, and working with the industry on educational programs for dairy owners/operators. 
  • Installed both active and passive control measures to substantially reduce the discharge of acid mine drainage containing heavy metals at Iron Mountain Mine, Penn Mine, Walker Mine, Spenceville Mine, and the West Squaw Creek area mines Balaklala, Shasta King, Early Bird, Keystone and Stowell. 
  • Provided regulatory oversight, along with DTSC and USEPA of environmental remediation activities by Aerojet-General Corporation, which is commencing remediation of an approximately 14 square mile groundwater plume in the community of Rancho Cordova, including replacement of lost water supplies due to the pollution.
  • Together with the Department of Pesticide Regulation (DPR) and County agricultural commissioners, facilitated the use of best management practices to help minimize the movement into surface waters of the Sacramento River Basin of irrigation return flows containing pesticides used on rice fields.

Regional Board Offices

  • Fresno Office
    • 1685 "E" Street
    • Fresno, CA 93706-2007
    • Phone: (559) 445-5116 CalNet: 8-421-5116
    • Fax: (559) 445-5910
    • Phone List
  • Redding Office
    • 364 Knollcrest Drive, Suite 205
    • Redding, CA 96002
    • Phone: (530) 224-4845 CalNet: 8-441-4845
    • Fax: (530) 224-4857
    • Phone List
  • Ombudsperson (Sacramento Office), (916) 464-4640

Contact Central Valley Regional Water Quality Control Board

Richard Loncarovich
11020 Sun Center Drive
Suite 200
Rancho Cordova, California  95670-6114
Phone: (916) 464-3291
Fax: (916) 464-4645


Service Area

Services provided in:
  • Amador County, California
  • Butte County, California
  • Calaveras County, California
  • Colusa County, California
  • Contra Costa County, California
  • El Dorado County, California
  • Fresno County, California
  • Glenn County, California
  • Kern County, California
  • Kings County, California
  • Lake County, California
  • Lassen County, California
  • Madera County, California
  • Mariposa County, California
  • Merced County, California
  • Modoc County, California
  • Napa County, California
  • Nevada County, California
  • Placer County, California
  • Plumas County, California
  • Sacramento County, California
  • San Benito County, California
  • San Joaquin County, California
  • San Luis Obispo County, California
  • Shasta County, California
  • Sierra County, California
  • Siskiyou County, California
  • Solano County, California
  • Stanislaus County, California
  • Sutter County, California
  • Tehama County, California
  • Tulare County, California
  • Tuolumne County, California
  • Yolo County, California
  • Yuba County, California

To request additions or corrections to this entry email the Administrator