A100/100
CALIFORNIA WATER SERVICE - STOCKTON — Water Quality Report 2026
Serving 176,266 people · California
Water Source
Purchased Surface Water
County
—
System ID
CA3910001
Violations
0
Contaminant Test Results
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
chlorate | 230.00 µg/L | — | Above Goal |
EPA Violation History
No violations in the past 5 years
This system has a clean compliance history.
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 - STOCKTON
Is CALIFORNIA WATER SERVICE - STOCKTON water safe to drink?
CALIFORNIA WATER SERVICE - STOCKTON water receives a grade of A (100/100), 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 - STOCKTON detected?
76 contaminants were tested in CALIFORNIA WATER SERVICE - STOCKTON's water. Notable contaminants include chlorate. No contaminants exceed EPA legal limits. 1 exceed EPA health goals (MCLGs).
Does CALIFORNIA WATER SERVICE - STOCKTON have any EPA violations?
No, CALIFORNIA WATER SERVICE - STOCKTON has zero EPA violations on record. This indicates consistent compliance with federal drinking water standards.
How many people does CALIFORNIA WATER SERVICE - STOCKTON serve?
CALIFORNIA WATER SERVICE - STOCKTON serves approximately 176,266 people, California.
What type of water does CALIFORNIA WATER SERVICE - STOCKTON provide?
CALIFORNIA WATER SERVICE - STOCKTON 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 CA3910001.
How does CALIFORNIA WATER SERVICE - STOCKTON compare to other utilities in California?
CALIFORNIA WATER SERVICE - STOCKTON scores 100/100 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.