B62/100
CITY OF STOCKTON — Water Quality Report 2026
Serving 191,302 people · California
Water Source
Surface Water
County
—
System ID
CA3910012
Violations
11
Contaminant Test Results
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
vanadium | 28.00 µg/L | — | Above Goal |
EPA Violation History
6
Violations (last 5yr)
2
Unresolved
3
Health-Related
TIER 3Unresolved
Reporting violation
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
TIER 2Unresolved
Treatment technique violation
TIER 3Resolved
Exceeded the MCL for disinfection byproducts
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2024 – December 31, 2024Enforcement: Formal — state order issued
TIER 2Resolved
Exceeded the Maximum Contaminant Level (running average)
When: April 1, 2023 – June 30, 2023Rule: Stage 2 DBPREnforcement: Formal — state order issued
TIER 2Resolved
Exceeded the Maximum Contaminant Level (running average)
When: January 1, 2023 – March 31, 2023Rule: Stage 2 DBPREnforcement: Formal — state order issued
TIER 3Resolved
Failed to issue ongoing public notification
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: October 1, 2021Rule: Ground Water RuleEnforcement: Formal — state order issued
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 CITY OF STOCKTON
Is CITY OF STOCKTON water safe to drink?
CITY OF STOCKTON water receives a grade of B (62/100), which is considered good. 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 CITY OF STOCKTON detected?
76 contaminants were tested in CITY OF STOCKTON's water. Notable contaminants include vanadium. No contaminants exceed EPA legal limits. 1 exceed EPA health goals (MCLGs).
Does CITY OF STOCKTON have any EPA violations?
Yes, CITY OF STOCKTON has 11 EPA violation(s) on record, with the most recent in 2024. Violation types include RPT, TT, MR. 6 are health-based violations.
How many people does CITY OF STOCKTON serve?
CITY OF STOCKTON serves approximately 191,302 people, California. The system provides water to 1 community: Stockton.
What type of water does CITY OF STOCKTON provide?
CITY OF STOCKTON 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 CA3910012.
How does CITY OF STOCKTON compare to other utilities in California?
CITY OF STOCKTON scores 62/100 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.