COUNTY REPORT WI

Oneida County, Wisconsin

11 ZIP codes · Avg score 64/100 · Grade C · Updated 2026-06-03

Across Oneida County, EPA compliance data for 11 ZIP codes sits at a moderate level — not alarming, but not uniformly clean either.

How Oneida County Compares

Oneida County64/100
Wisconsin avg66/100
National avg68/100

How Oneida County Compares

C
County Grade
64/100
Avg Safety Score
11
ZIP Codes
13
Water Systems

Oneida County scores 2 points below the Wisconsin state average (66/100) and 4 points below the national average (68/100).

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

C
County Grade
64
Avg Safety Score
11
ZIP Codes
Best ZIP: 54539 (83/100)
Lowest ZIP: 54568 (53/100)
$263K
Median Home Value
$1,027
Avg Remediation (39% of home value)

ZIP Code Risk Map

Water Quality Map: Oneida County, Wisconsin

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: 14.5 (asthma 10.5%, diabetes 13.8%)

Estimated additional annual cost per homeowner: $525, driven primarily by energy_code_gap

Infrastructure: 0.362% avg pipe failure probability, 20% of ZIPs at high risk

58.2% of homes built before 1978 (lead paint era)

Violation History (2024–2025)

→ Stable trend

EPA violation counts by year across Oneida County water systems. Health-based shown in red, total in blue.

2024
10 (10 health)
2025
1 (1 health)

Peak year: 2024 with 10 violations. Past 5 years: 11 total (11 health-based).

Source: EPA SDWIS historical violations. Data may lag 6–12 months for the most recent year.

County Health Indicators vs National Average

Asthma 10.5% (national: 8.9%)
Diabetes 13.8% (national: 10.5%)
Obesity 36.1% (national: 32.4%)

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

Infrastructure Overview

1974
Median Build Year
58.2%
Pre-1978 Housing
36%
Pipe Failure Probability
20%
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: $525

Energy Code Gap $245/yr
Water / Lead $145/yr
Underground Tanks $80/yr

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

Housing Age Distribution

39,953 housing units in Oneida County

Pre-1940 9%
1940–1959 15%
1960–1979 27%
1980–1999 31%
2000+ 19%

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 Oneida County

$263K
Median Home Value
$1,027
Est. Remediation Cost
0.4%
of Home Value
Remediation as % of home value low burden

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

Asthma 10.5% (US avg: 8.9%)
Diabetes 13.8% (US avg: 11%)
Obesity 36.1% (US avg: 32.4%)

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

Water Systems with Most Violations

Top 5 systems in Oneida County ranked by EPA violation count.

# Water System Population Violations
1 Northernaire Sanitary District 315 18
2 Three Lakes Sanitary District 500 18
3 LAKELAND SANITARY DIST 1 2,381 10
4 Lakeland Village 1 81 10
5 Patricia Lake Manufactured Housing Community 56 10

13 total water systems serve Oneida County.

All ZIP Codes in Oneida County

11 ZIP codes tracked in Oneida County.

# ZIP Code City Safety Score Grade Violations Home Value
1 54539 Lake Tomahawk 83 B 0 $241K
2 54501 Rhinelander 82 B 5 (1 health) $195K
3 54521 Eagle River 82 B 7 (1 health) $276K
4 54548 Minocqua 82 B 10 (1 health) $308K
5 54562 Three Lakes 59 C 18 (3 health) $292K
6 54529 Harshaw 53 D 0 $264K
7 54531 Hazelhurst 53 D 0 $323K
8 54543 Mc Naughton 53 D 0
9 54558 Saint Germain 53 D 0 $235K
10 54560 Sayner 53 D 0 $218K
11 54568 Woodruff 53 D 0 $262K

Recommended Buyer Guides for Oneida County

Strictly editorial — no paid placements influence which guides appear; the selection draws on NSF certifications and EPA detection records for water systems serving this county.

Overview

Oneida County in Wisconsin covers 11 ZIP codes with an average Home Safety Score of C (64/100).

4 of 11 ZIP codes have recorded EPA violations. 6 health-based violations have been documented.

← Back to Wisconsin water quality report

Data Sources

Updated daily.

Frequently Asked Questions

Is water safe in Oneida County?
Oneida County receives a grade of C. Some ZIP codes have recorded violations and residents in affected areas may want to test their water.
How many water systems serve Oneida County?
Oneida County is served by 13 public water systems that supply drinking water to residents across 11 ZIP codes.
What is the biggest environmental risk in Oneida County?
The primary environmental risk factor in Oneida County is energy_code_gap. This contributes to an estimated additional annual cost of $525 per homeowner.
How old are homes in Oneida County?
The median home build year in Oneida County is 1974. 58.2% of homes were built before 1978, which means they may contain lead-based paint and older plumbing materials.
How does Oneida County compare to Wisconsin?
Oneida County has an average water safety score of 64/100, which is below the Wisconsin state average of 66/100.

Get safety alerts for Oneida, Wisconsin

Free updates when EPA data changes for this area. No spam.

Unsubscribe anytime. Privacy Policy.

Share This Page

X Facebook
Check your water filter options Free tool — no phone call required.