Napa County, California
13 ZIP codes · Home Safety Score unavailable · 0 of 13 tracked ZIP records scored · Updated
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: Napa County, California
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 11.6 (asthma 9.5%, diabetes 11.4%)
Estimated additional annual cost per homeowner: $2,793, driven primarily by flood
69.4% of homes built before 1978 (lead paint era)
Violation History (2021–2024)
↓ Improving trendEPA violation counts by year across Napa County water systems. Health-based shown in red, total in blue.
Peak year: 2022 with 14 violations. Past 5 years: 33 total (33 health-based). Health-based violations are declining versus the prior 2-year window.
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: $2,793
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
74,082 housing units in Napa 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 Napa County
Remediation costs are relatively manageable for most homeowners in Napa 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 Napa County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water systems serving Napa County
8 community water systems serving Napa County.
Show all 8 water systems
17 total water systems serve Napa County.
Systems with the most violations in Napa County
5 water systems with recorded EPA violations.
All ZIP Codes in Napa County
13 ZIP codes tracked in Napa County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 94503 | American Canyon | — | — | 2 (1 health) | $664K |
| 2 | 94508 | Angwin | — | — | 2 (2 health) | $775K |
| 3 | 94515 | Calistoga | — | — | 6 (5 health) | $831K |
| 4 | 94550 | Livermore | — | — | 0 | $1147K |
| 5 | 94558 | Napa | — | — | 2 | $856K |
| 6 | 94559 | Napa | — | — | 0 | $877K |
| 7 | 94562 | Oakville | — | — | — | |
| 8 | 94567 | Pope Valley | — | — | 2 (2 health) | $386K |
| 9 | 94573 | Rutherford | — | — | — | |
| 10 | 94574 | Saint Helena | — | — | 9 (8 health) | $1877K |
| 11 | 94576 | Deer Park | — | — | 2 (2 health) | $1059K |
| 12 | 94581 | Napa | — | — | — | |
| 13 | 94599 | Yountville | — | — | 3 (1 health) | $757K |
Recommended Buyer Guides for Napa County
Editorial-only picks, screened against the EPA detections on file.
- Best Lead Paint Test Kits — 69.4% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- Best Sump Pumps — Flood is the top compound risk factor
- Best Mold Test Kits — Flood-driven moisture and mold risk
Deep Dive Reports
Detailed analysis for Napa County, California
Overview
Napa County in California covers 13 tracked ZIP records. No Home Safety Score is published because the required model evidence is incomplete for every tracked record; missing evidence is not treated as zero.
8 of 10 ZIP codes with a reported violation count in the available EPA record have recorded EPA violations. 13 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.