St. Croix County, Wisconsin
13 ZIP codes · Avg score 66/100 · Grade C · Updated 2026-06-03
St. Croix County: 13 ZIP codes, mid-range safety grade.
How St. Croix County Compares
How St. Croix County Compares
St. Croix County scores 0 points above the Wisconsin state average (66/100) and 2 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: St. Croix 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 (asthma 10.4%, diabetes 9.6%)
Estimated additional annual cost per homeowner: $768, driven primarily by flood
Infrastructure: 0.33% avg pipe failure probability, 8% of ZIPs at high risk
48.3% of homes built before 1978 (lead paint era)
Violation History (2021–2024)
→ Stable trendEPA violation counts by year across St. Croix County water systems. Health-based shown in red, total in blue.
Peak year: 2024 with 7 violations. Past 5 years: 9 total (9 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: $768
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
44,191 housing units in St. Croix 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 St. Croix County
Remediation costs are relatively manageable for most homeowners in St. Croix 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 St. Croix 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 St. Croix County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Houlton Mhp Llc | 170 | 10 |
| 2 | Somerset Waterworks | 2,854 | 10 |
| 3 | Hudson Waterworks | 17,635 | 8 |
| 4 | Country Cove Court Llc | 150 | 8 |
| 5 | Glenwood City Waterworks | 1,102 | 6 |
20 total water systems serve St. Croix County.
All ZIP Codes in St. Croix County
13 ZIP codes tracked in St. Croix County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 54013 | Glenwood City | 70 | B | 0 | $269K |
| 2 | 54015 | Hammond | 70 | B | 0 | $286K |
| 3 | 54023 | Roberts | 70 | B | 1 | $353K |
| 4 | 54025 | Somerset | 69 | C | 6 (1 health) | $343K |
| 5 | 54028 | Woodville | 69 | C | 2 | $249K |
| 6 | 54082 | Houlton | 69 | C | 2 | $480K |
| 7 | 54022 | River Falls | 68 | C | 5 (2 health) | $350K |
| 8 | 54026 | Star Prairie | 66 | C | 0 | $305K |
| 9 | 54027 | Wilson | 65 | C | 6 (1 health) | $324K |
| 10 | 54002 | Baldwin | 64 | C | 2 | $276K |
| 11 | 54016 | Hudson | 61 | C | 8 (1 health) | $426K |
| 12 | 54017 | New Richmond | 61 | C | 2 (1 health) | $302K |
| 13 | 54734 | Downing | 53 | D | 0 | $209K |
Recommended Buyer Guides for St. Croix County
Below: editorial picks, no sponsored placements.
- 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
- 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 St. Croix County, Wisconsin
Overview
St. Croix County in Wisconsin covers 13 ZIP codes with an average Home Safety Score of C (66/100).
9 of 13 ZIP codes have recorded EPA violations. 6 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.