COUNTY REPORT ID

Washington County, Idaho

3 ZIP codes · Avg score 80/100 · Grade B · Updated 2026-06-03

Based on current EPA data, Washington County's 3 ZIP codes maintain an above-average drinking water safety record.

How Washington County Compares

Washington County80/100
Idaho avg66/100
National avg68/100

How Washington County Compares

B
County Grade
80/100
Avg Safety Score
3
ZIP Codes
2
Water Systems

Washington County scores 14 points above the Idaho state average (66/100) and 12 points above the national average (68/100).

Data: EPA SDWIS Last verified: 2026-06-03

B
County Grade
80
Avg Safety Score
3
ZIP Codes
Best ZIP: 83610 (88/100)
Lowest ZIP: 83645 (73/100)
$262K
Median Home Value
$1,800
Avg Remediation (69% of home value)

Key Risk Factors

Health risk index: 14.7 (asthma 11.1%, diabetes 14.5%)

Estimated additional annual cost per homeowner: $1,257, driven primarily by energy_code_gap

Infrastructure: 0.373% avg pipe failure probability

61.3% of homes built before 1978 (lead paint era)

County Health Indicators vs National Average

Asthma 11.1% (national: 8.9%)
Diabetes 14.5% (national: 10.5%)
Obesity 33.4% (national: 32.4%)

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

Infrastructure Overview

1972
Median Build Year
61.3%
Pre-1978 Housing
37%
Pipe Failure Probability
0%
ZIPs at High Infra Risk
Low
Lead Pipe Risk

Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.

Compound Risk Breakdown

Estimated additional annual cost per homeowner: $1,257

Energy Code Gap $540/yr
Wildfire $300/yr
Flood $267/yr

Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).

Housing Age Distribution

4,551 housing units in Washington County

Pre-1940 21%
1940–1959 11%
1960–1979 28%
1980–1999 22%
2000+ 18%

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 Washington County

$262K
Median Home Value
$1,800
Est. Remediation Cost
0.7%
of Home Value
Remediation as % of home value low burden

Remediation costs are relatively manageable for most homeowners in Washington 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 Washington County residents

Asthma 11.1% (US avg: 8.9%)
Diabetes 14.5% (US avg: 11%)
Obesity 33.4% (US avg: 32.4%)

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

All ZIP Codes in Washington County

3 ZIP codes tracked in Washington County.

# ZIP Code City Safety Score Grade Violations Home Value
1 83610 Cambridge 88 A 7 $262K
2 83672 Weiser 80 B 1 $244K
3 83645 Midvale 73 B 0 $297K

Recommended Buyer Guides for Washington County

Four sources — EPA, NSF, FEMA, CDC — drive the match.

Overview

Washington County in Idaho covers 3 ZIP codes with an average Home Safety Score of B (80/100).

2 of 3 ZIP codes have recorded EPA violations. All violations are monitoring/reporting type.

← Back to Idaho water quality report

Data Sources

Updated daily.

Frequently Asked Questions

Is water safe in Washington County?
Washington County receives a grade of B, indicating generally safe tap water across its 3 ZIP codes.
How many water systems serve Washington County?
Washington County is served by 2 public water systems that supply drinking water to residents across 3 ZIP codes.
What is the biggest environmental risk in Washington County?
The primary environmental risk factor in Washington County is energy_code_gap. This contributes to an estimated additional annual cost of $1,257 per homeowner.
How old are homes in Washington County?
The median home build year in Washington County is 1972. 61.3% of homes were built before 1978, which means they may contain lead-based paint and older plumbing materials.
How does Washington County compare to Idaho?
Washington County has an average water safety score of 80/100, which is above the Idaho state average of 66/100.

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