D25/100
SAN JOAQUIN, CITY OF — Water Quality Report 2026
Serving 4,060 people · California
Water Source
Groundwater
County
—
System ID
CA1010034
Violations
20
Contaminant Test Results
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
manganese | 410.00 µg/L | — | Above Goal |
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2010.
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 SAN JOAQUIN, CITY OF
Is SAN JOAQUIN, CITY OF water safe to drink?
SAN JOAQUIN, CITY OF water receives a grade of D (25/100), which is considered poor. 0 contaminant(s) exceed EPA legal limits and 20 violation(s) are on record. Customers may want to consider using a water filter.
What contaminants has SAN JOAQUIN, CITY OF detected?
51 contaminants were tested in SAN JOAQUIN, CITY OF's water. Notable contaminants include manganese. No contaminants exceed EPA legal limits. 1 exceed EPA health goals (MCLGs).
Does SAN JOAQUIN, CITY OF have any EPA violations?
Yes, SAN JOAQUIN, CITY OF has 20 EPA violation(s) on record, with the most recent in 2010. Violation types include MCL, MR, Other. 13 are health-based violations.
How many people does SAN JOAQUIN, CITY OF serve?
SAN JOAQUIN, CITY OF serves approximately 4,060 people, California. The system provides water to 1 community: San Joaquin.
What type of water does SAN JOAQUIN, CITY OF provide?
SAN JOAQUIN, CITY OF sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is CA1010034.
How does SAN JOAQUIN, CITY OF compare to other utilities in California?
SAN JOAQUIN, CITY OF scores 25/100 with a grade of D (poor). This score suggests significant water quality concerns relative to other utilities. Visit our California state page for a full comparison of water systems.