A86/100
CALIFORNIA WATER SERVICE-S SAN FRANCISCO — Water Quality Report 2026
Serving 64,146 people · California
Water Source
Purchased Surface Water
County
—
System ID
CA4110009
Violations
3
Contaminant Test Results
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Lead (90th percentile) | 0.002 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2013.
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 CALIFORNIA WATER SERVICE-S SAN FRANCISCO
Is CALIFORNIA WATER SERVICE-S SAN FRANCISCO water safe to drink?
CALIFORNIA WATER SERVICE-S SAN FRANCISCO water receives a grade of A (86/100), which is considered excellent. Out of 76 contaminants tested, none exceed EPA legal limits. 1 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has CALIFORNIA WATER SERVICE-S SAN FRANCISCO detected?
76 contaminants were tested in CALIFORNIA WATER SERVICE-S SAN FRANCISCO's water. Notable contaminants include Lead (90th percentile). No contaminants exceed EPA legal limits. 1 exceed EPA health goals (MCLGs).
Does CALIFORNIA WATER SERVICE-S SAN FRANCISCO have any EPA violations?
Yes, CALIFORNIA WATER SERVICE-S SAN FRANCISCO has 3 EPA violation(s) on record, with the most recent in 2013. Violation types include MR, TT, MCL. 2 are health-based violations.
How many people does CALIFORNIA WATER SERVICE-S SAN FRANCISCO serve?
CALIFORNIA WATER SERVICE-S SAN FRANCISCO serves approximately 64,146 people, California.
What type of water does CALIFORNIA WATER SERVICE-S SAN FRANCISCO provide?
CALIFORNIA WATER SERVICE-S SAN FRANCISCO sources its water from purchased surface water. Surface water comes from rivers, lakes, or reservoirs and typically requires more extensive treatment. The utility's system ID is CA4110009.
How does CALIFORNIA WATER SERVICE-S SAN FRANCISCO compare to other utilities in California?
CALIFORNIA WATER SERVICE-S SAN FRANCISCO scores 86/100 with a grade of A (excellent). This places it among the higher-performing utilities in the state. Visit our California state page for a full comparison of water systems.