Tuolumne County, California
15 ZIP codes · Avg score 75/100 · Grade B · Updated
ZipCheckup grade for Tuolumne County: B.
This ZIP looks solid, with a few items worth a quick check.
In current tracking cycles, Tuolumne County - spanning 15 ZIP codes - records above-average water quality outcomes; the county's compliance history over recent years shows few departures from federal standards.
How Tuolumne County Compares
How Tuolumne County Compares
Tuolumne County scores 1 points below the California state average (76/100) and 2 points above the national average (73/100).
Data: ZipCheckup Home Safety Score model 4.0.0; EPA SDWIS, UCMR 5, EPA radon zones, EPA AirData Last verified:
ZIP Code Risk Map
Water Quality Map: Tuolumne County, California
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 13.2 (asthma 10.3%, diabetes 12.1%)
Estimated additional annual cost per homeowner: $2,245, driven primarily by wildfire
71.7% of homes built before 1978 (lead paint era)
Violation History (2021–2025)
→ Stable trendEPA violation counts by year across Tuolumne County water systems. Health-based shown in red, total in blue.
Peak year: 2024 with 11 violations. Past 5 years: 18 total (18 health-based).
Source: EPA SDWIS historical violations. Data may lag 6–12 months for the most recent year.
County Health Indicators vs National Average
Black markers indicate national averages. Source: CDC PLACES, Census ACS.
Infrastructure Overview
Modeled area-level indicator, not a failure probability. Sources: Census ACS housing age, EPA DWINS infrastructure needs, EPA SDWIS violations, and EPA lead indicators.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $2,245
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
30,405 housing units in Tuolumne County
Source: U.S. Census Bureau ACS B25034 (Year Structure Built).
Water Safety Affordability
How much it costs to fix water issues relative to home values in Tuolumne County
Remediation costs are relatively manageable for most homeowners in Tuolumne County, representing a small fraction of property value.
Remediation includes water filtration, lead abatement, radon mitigation, and flood protection where applicable. Source: Census ACS, EPA SDWIS.
Health Outcomes vs National Average
CDC PLACES data for Tuolumne County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water systems serving Tuolumne County
8 community water systems serving Tuolumne County.
- B
- B
- B
- C
- B
- B
Show all 8 water systems
- B
- B
14 total water systems serve Tuolumne County.
Systems with the most violations in Tuolumne County
5 water systems with recorded EPA violations.
- C
- B
- B
- B
All ZIP Codes in Tuolumne County
15 ZIP codes tracked in Tuolumne County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 95310 | Columbia | 83 | B | 1 | $449K |
| 2 | 95372 | Soulsbyville | 83 | B | 1 | $354K |
| 3 | 95379 | Tuolumne | 83 | B | 1 | $405K |
| 4 | 95327 | Jamestown | 77 | B | 8 (1 health) | $367K |
| 5 | 95370 | Sonora | 76 | B | 13 (1 health) | $416K |
| 6 | 95383 | Twain Harte | 70 | B | 13 (2 health) | $454K |
| 7 | 95305 | Big Oak Flat | 56 | C | 10 (4 health) | — |
| 8 | 95309 | Chinese Camp | — | — | — | |
| 9 | 95321 | Groveland | — | — | 5 (3 health) | $377K |
| 10 | 95335 | Long Barn | — | — | $248K | |
| 11 | 95346 | Mi Wuk Village | — | — | 12 (2 health) | $516K |
| 12 | 95347 | Moccasin | — | — | — | |
| 13 | 95364 | Pinecrest | — | — | — | |
| 14 | 95373 | Standard | — | — | — | |
| 15 | 95375 | Strawberry | — | — | — |
Recommended Buyer Guides for Tuolumne County
Eight risk categories drive the selection - PFAS exceedance, lead above EPA action level, pre-1978 housing share, EPA Radon Zone 1, flood-top-risk, wildfire-top-risk, multi-contaminant load, and a baseline fallback - and each category maps to a specific buyer-guide track that surfaces when the county data hits its threshold for that hazard signal.
- Best Lead Paint Test Kits — 71.7% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- Best HEPA Air Purifiers for Wildfire Smoke — Wildfire is the top compound risk factor
Deep Dive Reports
Detailed analysis for Tuolumne County, California
Overview
Tuolumne County in California covers 15 tracked ZIP records with an average Home Safety Score of B (75/100) across 7 scored records.
9 of 9 ZIP codes with a reported violation count in the available EPA record have recorded EPA violations. 7 health-based violations appear in the available health breakdown.
← Back to California Home Safety Profile
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- PFAS screening: EPA UCMR 5
- Radon zones: EPA Map of Radon Zones
- Air quality: EPA AirData annual AQI
- Home values: U.S. Census Bureau ACS (median estimates by ZCTA)
Reporting periods vary by source. Missing data is shown as unavailable, not as zero.