Marathon County, Wisconsin
17 ZIP codes · Avg score 60/100 · Grade C · Updated 2026-06-03
For most households in Marathon County, the 17 tracked ZIP codes show adequate but uneven water quality.
How Marathon County Compares
How Marathon County Compares
Marathon County scores 6 points below the Wisconsin state average (66/100) and 8 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Marathon County, Wisconsin
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 12.8 (asthma 10.2%, diabetes 10.8%)
Estimated additional annual cost per homeowner: $779, driven primarily by energy_code_gap
Infrastructure: 0.385% avg pipe failure probability, 35% of ZIPs at high risk
64.4% of homes built before 1978 (lead paint era)
Violation History (2023–2024)
→ Stable trendEPA violation counts by year across Marathon County water systems. Health-based shown in red, total in blue.
Peak year: 2024 with 13 violations. Past 5 years: 14 total (14 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
Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $779
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
59,205 housing units in Marathon 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 Marathon County
Remediation costs are relatively manageable for most homeowners in Marathon 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 Marathon County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water Systems with Most Violations
Top 5 systems in Marathon County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Wausau Waterworks | 39,994 | 43 |
| 2 | Edgewood Country Estates | 49 | 42 |
| 3 | Rib Mountain Water Utility | 6,398 | 39 |
| 4 | Maine Water Utility | 271 | 39 |
| 5 | Prairie Meadow Estates 1 | 50 | 39 |
24 total water systems serve Marathon County.
All ZIP Codes in Marathon County
17 ZIP codes tracked in Marathon County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 54476 | Schofield | 70 | B | 1 | $211K |
| 2 | 54414 | Birnamwood | 69 | C | 2 | $186K |
| 3 | 54403 | Wausau | 67 | C | 13 (1 health) | $179K |
| 4 | 54448 | Marathon | 67 | C | 4 | $239K |
| 5 | 54421 | Colby | 66 | C | 0 | $179K |
| 6 | 54455 | Mosinee | 66 | C | 3 (1 health) | $227K |
| 7 | 54440 | Hatley | 65 | C | 2 | $201K |
| 8 | 54479 | Spencer | 65 | C | 4 (1 health) | $175K |
| 9 | 54484 | Stratford | 65 | C | 3 (1 health) | $234K |
| 10 | 54401 | Wausau | 62 | C | 13 (1 health) | $186K |
| 11 | 54402 | Wausau | 62 | C | 13 (1 health) | — |
| 12 | 54426 | Edgar | 61 | C | 2 (1 health) | $205K |
| 13 | 54474 | Rothschild | 58 | C | 2 (1 health) | $184K |
| 14 | 54473 | Rosholt | 53 | D | 0 | $229K |
| 15 | 54411 | Athens | 42 | D | 2 | $211K |
| 16 | 54417 | Brokaw | 40 | D | 0 | — |
| 17 | 54471 | Ringle | 40 | D | 0 | $275K |
Recommended Buyer Guides for Marathon County
Four sources — EPA, NSF, FEMA, CDC — drive the match.
- Best Lead Paint Test Kits — 64.4% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county
Deep Dive Reports
Detailed analysis for Marathon County, Wisconsin
Overview
Marathon County in Wisconsin covers 17 ZIP codes with an average Home Safety Score of C (60/100).
13 of 17 ZIP codes have recorded EPA violations. 8 health-based violations have been documented.
← Back to Wisconsin water quality report
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Home values: U.S. Census Bureau ACS (median estimates by ZCTA)
Updated daily.