We deliver safe, clean water to approximately 500,000 people in central and eastern Contra Costa County in northern California. Formed in May 1936 to provide water for irrigation and industry, the District is now one of the largest urban water districts in California and a leader in drinking water treatment technology and source water protection. See CCWD's original incorporation document (PDF) from May 9, 1936. The District’s water source is the Sacramento-San Joaquin Delta. Learn more about our source of water.
In addition to providing drinking water to residences and businesses in our community, we also serve approximately 15 major industrial customers and 25 agricultural customers in the area.
We own and operate many facilities that store, move, and treat your water. Below are details about all the facilities and various types of infrastructure supporting your water system.
Sacramento-San Joaquin Delta water is diverted from four intakes: the Rock Slough Intake near Oakley, the Old River Intake near Discovery Bay, the Middle River Intake on Victoria Canal and the Mallard Slough Intake in Bay Point. Depending on the intake and where water is needed, the water is diverted into the Contra Costa Canal and conveyed to treatment plants and reservoirs located throughout eastern and central Contra Costa County or to Los Vaqueros Reservoir and Contra Loma Reservoir for storage and future use.
Contra Costa Canal
Part of the Central Valley Project, the Contra Costa Canal is the backbone of the Contra Costa Water District, delivering water from the Delta to the District's treatment facilities and untreated water customers. The canal is a 48-mile long facility that starts at Rock Slough, where four stations lift water 124 feet above sea level, and ends at the Martinez Reservoir.
After passing through a fish protection barrier and flood protection facility, the canal travels through a short unlined channel before entering a 1½-mile 10-foot diameter pipeline on its way to the concrete-lined section of the canal in Oakley. Middle River and Old River water is delivered by pipeline either to the Los Vaqueros Reservoir or to the Contra Costa Canal in Antioch where a hydroelectric turbine generates nearly one megawatt of electricity.
Los Vaqueros Conveyance System
Several large diameter buried pipelines transport water from the Middle River and Old River intakes to a Transfer Station outside of Brentwood, where water is then pumped south to the Los Vaqueros Reservoir or travels north to the Contra Costa Canal by gravity. Learn more about Los Vaqueros.
Dams and Levees
We oversee four dams and two levees within our water system. Learn more about these facilities and our Dam Safety Program.
Water Treatment Facilities
Ralph D. Bollman Water Treatment Plant, Concord
Conventional treatment (coagulation, flocculation, sedimentation); mixed media GAC (granular activated carbon) filtration; and intermediate ozonation. Capacity: 75 million gallons per day. Learn more about the Ralph D. Bollman Water Treatment Plant (PDF).
Randall-Bold Water Treatment Plant, Oakley
Conventional treatment (coagulation, flocculation, sedimentation); dual media GAC (granular activated carbon) filtration; intermediate and post ozonation. Jointly owned by Diablo Water District and CCWD. Capacity: 50 million gallons per day. Learn more about the Randall-Bold Water Treatment Plant (PDF).
CCWD/Brentwood Water Treatment Plant, Oakley
Conventional treatment (coagulation, flocculation, sedimentation); dual media GAC (granular activated carbon) filtration; and intermediate ozonation. Built and operated for the City of Brentwood. Capacity: 16.5 million gallons per day.
|Treated Water Facilities|
|Reservoir Storage Capacity|
|Martinez Reservoir||270 acre-feet|
|Contra Loma Reservoir||2,500 acre-feet|
|Mallard Reservoir||3,000 acre-feet|
|Los Vaqueros Reservoir||160,000 acre-feet|