Coulterville, CA Water Safety: 53/100 (2026)
1 ZIP code · 2 water systems · Updated 2026-06-03
Coulterville, CA water systems: poor compliance record, lower-tier safety grade.
How Coulterville Compares
Data: EPA SDWIS Last verified: 2026-06-03
Key Facts for Coulterville Residents
- Homes built before 1986: 54% — older plumbing may contain lead solder.
- Estimated remediation: $400 per household.
- CDC health risk index: 14 — above typical levels.
Coulterville's Water Providers
Water supply in Coulterville, CA follows a divided structure: 2 utilities account for the largest share of residential service out of 2 total systems, each managing its own distribution network and EPA reporting. Because these systems operate independently, rate decisions and compliance outcomes are determined separately.
Overview
We track water quality and home safety data for 1 ZIP code in Coulterville, California (population ~2,282), covering 2 community water systems serving approximately 6,640 people region-wide.
No EPA violations recorded across any ZIP codes in Coulterville — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Coulterville: D (53/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Coulterville water systems draw from: Surface water.
Lead & Copper
- Lead data: not yet available for Coulterville
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 95311 | D | GROVELAND COMMUNITY SERV DIST | 3,400 |
All ZIP Codes in Coulterville
- 95311 [D]
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
Coulterville Community Health Snapshot
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Coulterville Infrastructure Age
With 54% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Federal plumbing rules changed in two stages — lead pipes were phased out before 1970, and lead solder was banned in 1986 — but in Coulterville, where the median build year is 1985, most of the housing was already in place before those rules took effect. The materials installed under older standards remain embedded in a substantial portion of the residential inventory today.
Over half of homes in Coulterville were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
How Remediation Costs Compare in Coulterville
In Coulterville, property values comfortably outpace what documented remediation typically costs — the equity share is proportionally low.
Remediation costs in Coulterville are relatively low compared to home values. The $0–$800 estimated range is a small fraction of median property value. Home values are 60% below the California average.
Coulterville: Lead Risk & Vulnerable Populations
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
Locally, 54% of Coulterville homes carry interior plumbing from the era when lead solder was still permitted in new builds, and citywide monitoring approaches or crosses the EPA action benchmark. Households can find a draw-test kit and certified filtration through verified retailers.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
What You Can Do in Coulterville
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. An NSF-certified pitcher or under-sink filter removes most common contaminants.
- Check your home's plumbing. With 54% of homes built before 1986, lead solder is a real possibility.
- Review your water system's CCR. Your utility publishes an annual Consumer Confidence Report with detailed test results. Request it or find it online.
Deep Dive Reports
Detailed analysis for Coulterville, CA