Carroll County, Illinois
7 ZIP codes · Avg score 58/100 · Grade C · Updated 2026-06-03
For most households in Carroll County, the 7 tracked ZIP codes show adequate but uneven water quality.
How Carroll County Compares
How Carroll County Compares
Carroll County scores 3 points below the Illinois state average (61/100) and 10 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Carroll County, Illinois
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 14.6 (asthma 10.1%, diabetes 13.3%)
Estimated additional annual cost per homeowner: $1,201, driven primarily by energy_code_gap
Infrastructure: 0.471% avg pipe failure probability, 71% of ZIPs at high risk
76% 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: $1,201
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
8,391 housing units in Carroll 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 Carroll County
Water safety remediation is a moderate expense relative to home values. Most homeowners can address issues through staged improvements over time.
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 Carroll 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 Carroll County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Lanark | 1,504 | 7 |
| 2 | Mount Carroll | 1,479 | 6 |
| 3 | Savanna | 3,020 | 5 |
| 4 | Shannon | 801 | 3 |
| 5 | Thomson Maximum Security Center | 2,166 | 3 |
8 total water systems serve Carroll County.
All ZIP Codes in Carroll County
7 ZIP codes tracked in Carroll County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 61051 | Milledgeville | 70 | B | 0 | $101K |
| 2 | 61285 | Thomson | 67 | C | 3 | $165K |
| 3 | 61053 | Mount Carroll | 65 | C | 0 | $105K |
| 4 | 61074 | Savanna | 63 | C | 2 | $94K |
| 5 | 61014 | Chadwick | 60 | C | 2 (1 health) | $110K |
| 6 | 61046 | Lanark | 52 | D | 4 | $148K |
| 7 | 61078 | Shannon | 32 | F | 3 | $129K |
Recommended Buyer Guides for Carroll County
Methodologically, the recommendation order reflects severity in the federal record: contaminants flagged in EPA detection records for this county outrank generic water concerns, FEMA-confirmed hazard ratings shift emergency-related categories upward, and CDC lead-exposure markers govern when lead-test kits and certified filters appear at the top of the list.
- Best Water Filters for Lead — Lead above EPA action level in 1 ZIP code
- Best Lead Paint Test Kits — 76% 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 Carroll County, Illinois
Overview
Carroll County in Illinois covers 7 ZIP codes with an average Home Safety Score of C (58/100).
5 of 7 ZIP codes have recorded EPA violations. 1 health-based violation 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.