Tap Water Quality Report for Contra Costa, California
Track your tap water quality with EPA-verified data on contaminants, violations, and health guidelines, updated quarterly from official water system monitoring results.
Contra Costa, California tap water has 262 total contaminants, with 14 being above EPA standards and 160 being above InTheTap suggested standards. There are 0 active violations. The primary water source is not specified, serving 0 residents.
Water Systems (35)
35 water systems serve Contra Costa, California. Select one or more to filter the data below.
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Water Quality Analysis
Comprehensive analysis of your water quality, showing both detected contaminants and violations history. Note that exceeding EPA contaminant levels in a single test doesn't always constitute a violation, as violations typically require sustained exceedances or failure to follow required treatment protocols.
Water Analysis
View detected contaminants and concentration levels for your water system(s).