B78/100
PATTERSON, CITY OF — Water Quality Report 2026
Serving 23,304 people · California
Water Source
Groundwater
County
—
System ID
CA5010017
Violations
4
Contaminant Test Results
2 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
strontium | 3200.00 µg/L | — | Above Goal |
chlorate | 400.00 µg/L | — | Above Goal |
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2007.
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 PATTERSON, CITY OF
Is PATTERSON, CITY OF water safe to drink?
PATTERSON, CITY OF water receives a grade of B (78/100), which is considered good. Out of 66 contaminants tested, none exceed EPA legal limits. 2 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has PATTERSON, CITY OF detected?
66 contaminants were tested in PATTERSON, CITY OF's water. Notable contaminants include strontium, chlorate. No contaminants exceed EPA legal limits. 2 exceed EPA health goals (MCLGs).
Does PATTERSON, CITY OF have any EPA violations?
Yes, PATTERSON, CITY OF has 4 EPA violation(s) on record, with the most recent in 2007. Violation types include MCL, Other. 3 are health-based violations.
How many people does PATTERSON, CITY OF serve?
PATTERSON, CITY OF serves approximately 23,304 people, California. The system provides water to 1 community: Patterson.
What type of water does PATTERSON, CITY OF provide?
PATTERSON, CITY OF sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is CA5010017.
How does PATTERSON, CITY OF compare to other utilities in California?
PATTERSON, CITY OF 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.