Winneshiek County, Iowa
9 ZIP codes · Avg score 59/100 · Grade C · Updated 2026-06-04
Compared to top-scoring counties, Winneshiek County's 9 ZIP codes land in the middle tier — some meet standards cleanly, others carry documented violations, and the gap between the best and worst areas is wider than average.
How Winneshiek County Compares
How Winneshiek County Compares
Winneshiek County scores 0 points above the Iowa state average (59/100) and 9 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-04
ZIP Code Risk Map
Water Quality Map: Winneshiek County, Iowa
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 12.9 (asthma 9.6%, diabetes 11%)
Estimated additional annual cost per homeowner: $698, driven primarily by water_lead
Infrastructure: 0.476% avg pipe failure probability, 88% of ZIPs at high risk
74.4% of homes built before 1978 (lead paint era)
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: $698
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
8,619 housing units in Winneshiek 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 Winneshiek County
Remediation costs are relatively manageable for most homeowners in Winneshiek 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 Winneshiek 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 Winneshiek County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Decorah Water Department | 7,615 | 2 |
| 2 | Freeport Water District | 775 | 2 |
| 3 | Scenic View Estates | 78 | 2 |
| 4 | Sherman Place Water & Road, Inc. | 73 | 2 |
| 5 | Deerfield Heights Association | 28 | 2 |
14 total water systems serve Winneshiek County.
All ZIP Codes in Winneshiek County
9 ZIP codes tracked in Winneshiek County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 52144 | Fort Atkinson | 70 | B | 0 | $194K |
| 2 | 52168 | Spillville | 68 | C | 0 | $157K |
| 3 | 52132 | Calmar | 66 | C | 0 | $226K |
| 4 | 52133 | Castalia | 66 | C | 0 | $209K |
| 5 | 52161 | Ossian | 66 | C | 0 | $174K |
| 6 | 52165 | Ridgeway | 65 | C | 2 | $271K |
| 7 | 52101 | Decorah | 53 | D | 2 | $250K |
| 8 | 52149 | Highlandville | 40 | D | 0 | — |
| 9 | 52166 | Saint Lucas | 40 | D | 0 | $115K |
Recommended Buyer Guides for Winneshiek County
Filtered against federal data, fitted to local risks.
- Best Lead Paint Test Kits — 74.4% of homes built before 1978
- Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county
Deep Dive Reports
Detailed analysis for Winneshiek County, Iowa
Overview
Winneshiek County in Iowa covers 9 ZIP codes with an average Home Safety Score of C (59/100).
2 of 9 ZIP codes have recorded EPA violations. All violations are monitoring/reporting type.
← Back to Iowa 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.