B78/100
ALAMEDA COUNTY WATER DISTRICT — Water Quality Report 2026
Serving 344,000 people · California
Water Source
Surface Water
County
—
System ID
CA0110001
Violations
3
Contaminant Test Results
2 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Copper (90th percentile) | 1.80 mg/L | 1.30 mg/L | Over Limit |
chlorate | 480.00 µg/L | — | Above Goal |
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 1996.
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Frequently Asked Questions About ALAMEDA COUNTY WATER DISTRICT
Is ALAMEDA COUNTY WATER DISTRICT water safe to drink?
ALAMEDA COUNTY WATER DISTRICT water receives a grade of B (78/100), which is considered good. Out of 77 contaminants tested, 1 exceed EPA legal limits. 2 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has ALAMEDA COUNTY WATER DISTRICT detected?
77 contaminants were tested in ALAMEDA COUNTY WATER DISTRICT's water. Notable contaminants include Copper (90th percentile), chlorate. 1 exceed EPA legal limits (MCLs). 2 exceed EPA health goals (MCLGs).
Does ALAMEDA COUNTY WATER DISTRICT have any EPA violations?
Yes, ALAMEDA COUNTY WATER DISTRICT has 3 EPA violation(s) on record, with the most recent in 1996. Violation types include MCL, TT, MR. 2 are health-based violations.
How many people does ALAMEDA COUNTY WATER DISTRICT serve?
ALAMEDA COUNTY WATER DISTRICT serves approximately 344,000 people, California.
What type of water does ALAMEDA COUNTY WATER DISTRICT provide?
ALAMEDA COUNTY WATER DISTRICT sources its water from surface water. Surface water comes from rivers, lakes, or reservoirs and typically requires more extensive treatment. The utility's system ID is CA0110001.
How does ALAMEDA COUNTY WATER DISTRICT compare to other utilities in California?
ALAMEDA COUNTY WATER DISTRICT scores 78/100 with a grade of B (good). This is an above-average performance for utilities statewide. Visit our California state page for a full comparison of water systems.