COUNTY REPORT CA

Napa County, California

13 ZIP codes · Home Safety Score unavailable · 0 of 13 tracked ZIP records scored

Data: ZipCheckup Home Safety Score model 4.0.0; EPA SDWIS, UCMR 5, EPA radon zones, EPA AirData

Unavailable
0 of 13 tracked ZIP records scored
13
ZIP Codes
$843K
Median Home Value
$488
Avg Remediation (0.06% of home value)

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.

A B C D F

Key Risk Factors

Health risk index: 11.6 (asthma 9.5%, diabetes 11.4%)

Modeled additional annual cost estimate per homeowner: $2,435, largest modeled factor: Flood

58% of homes built before 1980 (lead paint was banned for residential use in 1978)

County Health Indicators vs National Average

Asthma 9.5% (national: 8.9%)
Diabetes 11.4% (national: 10.5%)
Obesity 27.9% (national: 32.4%)

Black markers indicate national averages. Source: CDC PLACES, Census ACS.

Infrastructure Overview

1973
Median Build Year
58%
Pre-1980 Housing
46/100
Infrastructure Stress Indicator
58%
ZIPs with High Infrastructure Stress
High
Lead Pipe Risk

Modeled area-level indicator, not a failure probability. Sources: Census ACS housing age, EPA DWINSA infrastructure needs, EPA SDWIS violations, and EPA lead indicators.

Compound Risk Breakdown

Estimated additional annual cost per homeowner: $2,435

Flood $1,220/yr
Sea Level Rise $600/yr
Energy Code Gap $565/yr

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

Pre-1940 7%
1940–1959 17%
1960–1979 34%
1980–1999 25%
2000+ 16%

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

$843K
Median Home Value
$488
Est. Remediation Cost
0.1%
of Home Value
Remediation as % of home value low burden

Modeled remediation costs in Napa County can be compared with the median property value; actual costs vary by property.

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

Asthma 9.5% (US avg: 8.9%)
Diabetes 11.4% (US avg: 11%)
Obesity 27.9% (US avg: 32.4%)

Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.

Water systems mapped to Napa County ZIP codes

8 community water systems mapped to Napa County ZIP codes; EPA may list more systems serving the county.

Show all 8 water systems

17 water systems mapped to Napa County ZIP codes in our data; EPA may list more systems serving the county.

Systems with the most violations in Napa County

5 water systems with violations in EPA records.

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

Selection follows a fixed set of rules applied to local records: signals such as PFAS detections, lead action-level exceedances on record, a large share of pre-1978 housing, EPA Radon Zone 1, or a top flood or wildfire risk each add a related guide, and when none applies, general water testing and filtration guides are shown instead.

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

Reporting periods vary by source. Missing data is shown as unavailable, not as zero.

Frequently Asked Questions

How many water systems serve Napa County?
We map 17 public water systems to 13 ZIP codes in our data for Napa County. EPA may list more systems serving the county, so this is not a full count.
What is the biggest environmental risk in Napa County?
In ZipCheckup's cost model, the factor with the largest estimated average annual cost in Napa County is flood. Across all modeled risk factors, the estimated average additional annual cost is $2,435 per homeowner; actual costs vary by home.
How old are homes in Napa County?
The median home build year in Napa County is 1973. 58% of homes were built before 1980; homes built before 1978 may contain lead-based paint, and older homes may have older plumbing materials.

How to cite this page

APA ZipCheckup. (2026). Napa County, California Home Safety Profile. https://zipcheckup.com/county/california/napa/
BibTeX
@misc{zipcheckup-county-california-napa,
  author = {{ZipCheckup}},
  title  = {{Napa County, California Home Safety Profile}},
  year   = {2026},
  url    = {https://zipcheckup.com/county/california/napa/}
}

Page version: October 2026.

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