District Profile

We deliver safe, clean water to approximately 500,000 people in central and eastern Contra Costa County in Northern California. Formed in 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. The District’s source of water is the Sacramento-San Joaquin Delta.

Service Area

2018 District Profile Map

Total Water Sales

Residential
$48,249,890
Municipal
20,244,880
Industrial
18,605,402
Commercial
9,368,328
Public Facilities and Other
5,169,024
Fiscal Year 2017 Sales
$101,637,524

Employees

299.5 full-time equivalents

Major Industrial Customers

Andeavor
Shell Oil
Foster Wheeler
Dow Chemical Company
Calpine
USS-POSCO
ECO Services
Eight other smaller industrial customers

Agricultural

25 customers

Facilities

Intakes

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.

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

Treated Water Facilities

Pipelines 888 miles
Storage Reservoirs 41
Pump Stations 31
Connections 61,550

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

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

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