County Water Quality Report

Contra Costa County, California

4 public water systems serving 440,087 residents

Data sources: EPA SDWIS EPA ECHO EWG Tap Water Database Utility CCRs ⓘ How did we get these ratings?
County average grade
D
64/100
Utilities rated 4
Population served 440,087

Top water quality concerns in Contra Costa County

  • Haloacetic acids (HAA5) significantly above health guidelinein 4 of 4 utilities
  • Total trihalomethanes (TTHMs) significantly above health guidelinein 4 of 4 utilities
  • Bromodichloromethane significantly above health guidelinein 2 of 4 utilities
  • Haloacetic acids (HAA9) significantly above health guidelinein 1 of 4 utilities
  • Chromium (hexavalent) significantly above health guidelinein 1 of 4 utilities

All utilities in Contra Costa County

Click any utility for full grade card, contaminant data, and treatment plant contact info.

C
67/100

CONTRA COSTA WATER DISTRICT

CONCORD · 198,000 residents

Top concern: Haloacetic acids (HAA5) significantly above health guideline

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C
65/100

CITY OF ANTIOCH

ANTIOCH · 115,074 residents

Top concern: Haloacetic acids (HAA5) significantly above health guideline

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D
64/100

BRENTWOOD

BRENTWOOD · 64,513 residents

Top concern: Haloacetic acids (HAA5) significantly above health guideline

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D
62/100

CITY OF PITTSBURG

PITTSBURG · 62,500 residents

Top concern: Total trihalomethanes (TTHMs) significantly above health guideline

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