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Coulterville, CA Tap Water Quality 2026

Water quality report for Coulterville, CA — PFAS, lead and copper results, violation history and state inspection findings from EPA SDWIS.

A look at Coulterville's drinking water using EPA enforcement records: violations, lead and copper results, PFAS sampling and state inspection findings.

Main Utility: Mpwd-Coulterville Csa 1 PWSID: CA2210901 Updated: 2026 Q2
✅

No federal limits exceeded on record

Lead is 1.40 ppb, 9% of the action level and no violations are open. PFAS has never been sampled at this system.

B

Coulterville earns a B for water quality

Graded on violations and lead, with state inspection findings. PFAS not tested.

Lead: 1.40 ppb — 9% of the federal action level
PFAS never sampled at this system
3 violations since 2015, 0 health-based
No violations currently open
Coulterville's lead level vs. all California community water systems
0 ppb5 ppb10 ppb15 ppb
Lead level: 1.40 ppb — 9% of the federal action level
✓ Lower lead than 77% of California utilities
Population Served
115
~83 connections
Water Source
Groundwater
Drawn from wells — SDWIS source code GW
Active Violations
0
3 since 2015, all resolved

Lead & Copper Testing

Lead (Pb)
90th percentile of tap samples collected across the distribution system
9% of EPA action level
1.40 ppb
Action level: 15 ppb
The 90th-percentile lead result is 1.40 ppb, 9% of the 15 ppb federal action level. The action level is a treatment trigger, not a legal maximum, and it is measured across sampled taps rather than at any single home.

Contaminant Violations (2015–Present)

ContaminantTypeMeasuredLimitPeriodStatus
Revised Total Coliform Rule MONITORING FAILURE — — 2022 Resolved
Revised Total Coliform Rule MONITORING FAILURE — — 2019 Resolved
Coliform (TCR) MONITORING AND REPORTING — 5% of samples 2015 Resolved
Understanding violation types MCL violations mean a contaminant exceeded the federal maximum limit — the most serious type.
TT (Treatment Technique) violations mean required treatment procedures weren't followed, but don't necessarily mean contamination occurred.

Violation History

3 violations are on record since 2015, of which 0 were health-based. All have been resolved and none remain open.

About the Main Water System

Utility Mpwd-Coulterville Csa 1
PWSID CA2210901
Water source Groundwater — Drawn from wells — SDWIS source code GW
Population served 115
Service connections 83
Systems serving this area 1
Regulator State primacy agency
Data through 2026 Q2 — EPA SDWIS

Frequently Asked Questions

Is Coulterville tap water safe to drink? ▼
No federal limit is exceeded on record. No violations are currently open. Lead is 1.40 ppb, 9% of the action level.
Does Coulterville water have PFAS? ▼
This system has never been sampled for PFAS. EPA's national monitoring covered systems serving 3,300 people or more, so no results exist — which is not evidence that none is present.
Who supplies water to Coulterville? ▼
Mpwd-Coulterville Csa 1 (PWSID CA2210901). Groundwater. Drawn from wells — SDWIS source code GW
When was this system last inspected? ▼
It was last inspected on 2025-06-25. No significant deficiencies were recorded.

What Should Coulterville Residents Do?

1
Read your annual water report
Your supplier publishes a Consumer Confidence Report each July covering the prior year.
2
Check for a lead service line
Lead reaches tap water mainly through service lines and household plumbing. Suppliers now publish an inventory identifying lead lines.
3
Flush before drinking
If water has sat in pipes more than six hours, run the cold tap for two minutes before drinking or cooking.

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