A81/100
Stockton Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 212,223 residents · California
What's In Stockton's Tap Water?
76
Contaminants Tested
0
Exceed EPA Limits
1
Above EPA Goals
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
Water Utility Details
FAIROAKS PWS #44
Population Served
1,172
Water Source
Groundwater
System ID
CA3901348
SAN JOAQUIN COUNTY - COLONIAL HEIGHTS
Population Served
1,841
Water Source
Purchased Surface Water
System ID
CA3910002
SAN JOAQUIN COUNTY - LINCOLN VILLAGE
Population Served
5,990
Water Source
Purchased Surface Water
System ID
CA3910010
CITY OF STOCKTON
Population Served
191,302
Water Source
Surface Water
System ID
CA3910012
SAN JOAQUIN COUNTY-RAYMUS VILLAGE
Population Served
1,086
Water Source
Groundwater
System ID
CA3910014
SAN JOAQUIN COUNTY-MOKELUMNE ACRES
Population Served
3,802
Water Source
Groundwater
System ID
CA3910017
OAKWOOD LAKE WATER DISTRICT-SUBDIVISION
Population Served
1,479
Water Source
Groundwater
System ID
CA3910023
CDCR CALIFORNIA HEALTH CARE FACILITY
Population Served
5,551
Water Source
Purchased Surface Water
System ID
CA3910803
Frequently Asked Questions About Stockton Water
Is Stockton tap water safe to drink?
Stockton, California tap water receives a grade of A (81/100), which is considered excellent. Out of 76 contaminants tested, 2 exceed EPA maximum contaminant levels (MCLs) and 3 exceed health guidelines (MCLGs). While the water meets federal standards, some residents may still choose to use a filter for additional peace of mind.
What contaminants are in Stockton's water?
Of the 76 contaminants tested in Stockton's water supply, the most notable include PFOS, PFOA, vanadium. 2 contaminant(s) exceed EPA legal limits (MCLs). 3 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Stockton have any water quality violations?
Yes, Stockton has 37 EPA violation(s) on record, with the most recent in 2025. Violation types include MCL, RPT, TT. 24 of these are health-based violations, which are the most serious category.
Do I need a water filter in Stockton?
Based on EPA data, using a water filter in Stockton is recommended. 2 contaminant(s) exceed legal limits. An NSF-certified filter — such as a reverse osmosis or activated carbon system — can effectively reduce many common contaminants. Choose a filter certified to remove the specific contaminants found in your area.
Where does Stockton's tap water come from?
Stockton's drinking water is sourced from groundwater and supplied by FAIROAKS PWS #44 and 7 other water system(s). The system serves approximately 212,223 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Stockton's water tested?
Under the Safe Drinking Water Act (SDWA), water utilities are required to regularly test for over 90 contaminants. Testing frequency varies by contaminant — some are tested monthly, others quarterly or annually. Stockton's water systems must report results to the EPA and publish an annual Consumer Confidence Report (CCR). The data on this page reflects the latest available EPA testing data.
How does Stockton's water compare to other cities in California?
Stockton's water quality score of 81/100 earns a grade of A, which is considered excellent. This places Stockton among the better-performing water systems in California. Visit our California state page to see how all cities in the state compare.
What should I do if I'm concerned about Stockton's water quality?
If you have concerns about Stockton's tap water, consider these steps: (1) Request your utility's annual Consumer Confidence Report for detailed local data. (2) Get your water independently tested through a state-certified laboratory. (3) Consider an NSF-certified water filter rated for the contaminants found in your area. (4) Contact your water utility (FAIROAKS PWS #44) with specific questions. (5) Report water quality issues to your state drinking water program or the EPA Safe Drinking Water Hotline at 800-426-4791.