County Water Quality Report

Alameda County, California

8 public water systems serving 2,848,633 residents

Data sources: EPA SDWIS EPA ECHO EWG Tap Water Database Utility CCRs ⓘ How did we get these ratings?
County average grade
D
60/100
Utilities rated 8
Population served 2,848,633
Most recent test 2024

Top water quality concerns in Alameda County

  • Haloacetic acids (HAA5) significantly above health guidelinein 6 of 8 utilities
  • PFAS contaminationin 4 of 8 utilities
  • Perfluorohexane sulfonate (PFHXS) significantly above health guidelinein 3 of 8 utilities
  • Total trihalomethanes (TTHMs) significantly above health guidelinein 3 of 8 utilities
  • Arsenic* significantly above health guidelinein 3 of 8 utilities

All utilities in Alameda County

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

B
76/100

Fremont Municipal Water System

Fremont · 230,000 residents

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

View report →
C
71/100

EAST BAY MUD

OAKLAND · 1,442,800 residents

Top concern: Haloacetic acids (HAA9) significantly above health guideline

View report →
C
68/100

City of Oakland Water Department

Oakland · 433,000 residents

Top concern: Lead detected in source water

View report →
C
65/100

CITY OF HAYWARD

HAYWARD · 162,954 residents

Top concern: Haloacetic acids (HAA9) significantly above health guideline

View report →
D
56/100

ALAMEDA COUNTY WATER DISTRICT

FREMONT · 344,000 residents

Top concern: PFAS contamination

View report →
F
50/100

CALIFORNIA WATER SERVICE - LIVERMORE

SAN JOSE · 60,414 residents

Top concern: PFAS contamination

View report →
F
50/100

DUBLIN SAN RAMON SERVICES DISTRICT

PLEASANTON · 98,776 residents

Top concern: PFAS contamination

View report →
F
47/100

CITY OF PLEASANTON

PLEASANTON · 76,689 residents

Top concern: PFAS contamination

View report →