The Contra Costa Water District is a special district public agency that delivers raw and treated water to a population of 500,0000 in central and eastern Contra Costa County in California.

Customers

Treated water customers include:

• Antioch (portion)
• Bay Point (portion)
• Brentwood (portion)
• Clayton
• Clyde
• Concord
• Martinez (portion)
• Pacheco
• Pleasant Hill (portion)
• Port Costa
• Walnut Creek

Raw water customers include:

• Antioch
• California Cities Water District (Bay Point)
• Diablo Water District (Oakley)
• Martinez
• Pittsburg