Winnebago County, Illinois
28 ZIP codes · Avg score 47/100 · Grade D · Updated 2026-06-03
Across Winnebago County, EPA compliance records for 28 ZIP codes fall well below average — documented health-based violations affect multiple areas, and the county's sustained low grade points to structural rather than temporary shortfalls in the underlying water systems.
How Winnebago County Compares
How Winnebago County Compares
Winnebago County scores 14 points below the Illinois state average (61/100) and 21 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Winnebago County, Illinois
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 14.4 (asthma 10.6%, diabetes 13.9%)
Estimated additional annual cost per homeowner: $1,562, driven primarily by flood
Infrastructure: 0.417% avg pipe failure probability, 39% of ZIPs at high risk
65.8% of homes built before 1978 (lead paint era)
Violation History (2021–2024)
↑ Worsening trendEPA violation counts by year across Winnebago County water systems. Health-based shown in red, total in blue.
Peak year: 2024 with 30 violations. Past 5 years: 45 total (45 health-based). Health-based violations are rising versus the prior 2-year window — worth closer monitoring.
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: $1,562
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
125,130 housing units in Winnebago 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 Winnebago County
Remediation costs are relatively manageable for most homeowners in Winnebago 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 Winnebago 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 Winnebago County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Rockford | 147,051 | 179 |
| 2 | Northgate Estates Mhp | 100 | 157 |
| 3 | Prairie Path Water Company-wildwood | 490 | 154 |
| 4 | Bill-mar Heights Mhp | 240 | 154 |
| 5 | Prairie Road Pump Corporation | 150 | 154 |
22 total water systems serve Winnebago County.
All ZIP Codes in Winnebago County
28 ZIP codes tracked in Winnebago County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 61063 | Pecatonica | 70 | B | 0 | $155K |
| 2 | 61088 | Winnebago | 70 | B | 0 | $193K |
| 3 | 61024 | Durand | 67 | C | 9 (2 health) | $154K |
| 4 | 61072 | Rockton | 64 | C | 15 (3 health) | $225K |
| 5 | 61080 | South Beloit | 61 | C | 3 (1 health) | $172K |
| 6 | 61130 | Loves Park | 61 | C | 5 | — |
| 7 | 61131 | Loves Park | 61 | C | 5 | — |
| 8 | 61132 | Loves Park | 61 | C | 5 | — |
| 9 | 61016 | Cherry Valley | 55 | C | 5 (2 health) | $225K |
| 10 | 61073 | Roscoe | 55 | C | 0 | $229K |
| 11 | 61111 | Loves Park | 55 | C | 5 | $144K |
| 12 | 61115 | Machesney Park | 54 | D | 1 | $161K |
| 13 | 61079 | Shirland | 53 | D | 0 | $114K |
| 14 | 61105 | Rockford | 43 | D | 11 (1 health) | — |
| 15 | 61110 | Rockford | 43 | D | 11 (1 health) | — |
| 16 | 61077 | Seward | 40 | D | 0 | — |
| 17 | 61101 | Rockford | 38 | F | 11 (1 health) | $90K |
| 18 | 61114 | Rockford | 38 | F | 11 (1 health) | $196K |
| 19 | 61102 | Rockford | 33 | F | 11 (1 health) | $95K |
| 20 | 61103 | Rockford | 33 | F | 11 (1 health) | $115K |
| 21 | 61107 | Rockford | 33 | F | 11 (1 health) | $165K |
| 22 | 61108 | Rockford | 33 | F | 11 (1 health) | $128K |
| 23 | 61109 | Rockford | 33 | F | 11 (1 health) | $125K |
| 24 | 61106 | Rockford | 31 | F | 11 (1 health) | — |
| 25 | 61112 | Rockford | 31 | F | 11 (1 health) | — |
| 26 | 61125 | Rockford | 31 | F | 11 (1 health) | — |
| 27 | 61126 | Rockford | 31 | F | 11 (1 health) | — |
| 28 | 61104 | Rockford | 28 | F | 11 (1 health) | $84K |
Recommended Buyer Guides for Winnebago 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.
- Best Lead Paint Test Kits — 65.8% 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
- 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 Winnebago County, Illinois
Overview
Winnebago County in Illinois covers 28 ZIP codes with an average Home Safety Score of D (47/100).
23 of 28 ZIP codes have recorded EPA violations. 22 health-based violations have been documented.
← Back to Illinois 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.
What You Can Do
Winnebago County has a grade of D. Here are steps to protect your household.
Test your tap water
Order a certified lab test kit ($20-$50) to check for lead, bacteria, and other contaminants specific to your ZIP code.
Consider a certified water filter
NSF-certified filters can remove most common contaminants. Match the filter to your test results for best protection. Try our filter matcher
Contact your water utility
Request the latest Consumer Confidence Report (CCR) from your water provider. It details exactly what was found in your water supply.
Check for lead in your home
65.8% of homes in this county were built before 1978. Older plumbing and solder can leach lead into drinking water, especially in the morning.