Johnson County, Illinois
11 ZIP codes · Avg score 64/100 · Grade C · Updated 2026-06-03
While Johnson County avoids the worst tiers, a portion of its 11 ZIP codes have logged violations.
How Johnson County Compares
How Johnson County Compares
Johnson County scores 3 points above the Illinois state average (61/100) and 4 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Johnson 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 10.2%, diabetes 12.9%)
Estimated additional annual cost per homeowner: $579, driven primarily by energy_code_gap
Infrastructure: 0.379% avg pipe failure probability, 50% of ZIPs at high risk
55.4% of homes built before 1978 (lead paint era)
Violation History (2024–2025)
→ Stable trendEPA violation counts by year across Johnson County water systems. Health-based shown in red, total in blue.
Peak year: 2024 with 34 violations. Past 5 years: 36 total (36 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: $579
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
7,571 housing units in Johnson 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 Johnson County
Remediation costs are relatively manageable for most homeowners in Johnson 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 Johnson 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 Johnson County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Goreville | 1,068 | 15 |
| 2 | Lake of Egypt Pwd | 11,368 | 13 |
| 3 | Buncombe Water District | 1,030 | 9 |
| 4 | VIENNA | 1,618 | 8 |
| 5 | Vienna Correctional Center | 501 | 6 |
13 total water systems serve Johnson County.
All ZIP Codes in Johnson County
11 ZIP codes tracked in Johnson County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 62939 | Goreville | 81 | B | 4 (2 health) | $161K |
| 2 | 62912 | Buncombe | 77 | B | 5 (5 health) | $104K |
| 3 | 62922 | Creal Springs | 77 | B | 3 (3 health) | $149K |
| 4 | 62967 | New Burnside | 72 | B | 2 (2 health) | $144K |
| 5 | 62908 | Belknap | 70 | B | 2 | $169K |
| 6 | 62943 | Grantsburg | 63 | C | 0 | $132K |
| 7 | 62909 | Boles | 53 | D | 0 | — |
| 8 | 62923 | Cypress | 53 | D | 0 | $71K |
| 9 | 62972 | Ozark | 53 | D | 0 | $174K |
| 10 | 62985 | Simpson | 53 | D | 0 | $156K |
| 11 | 62995 | Vienna | 51 | D | 6 | $136K |
Recommended Buyer Guides for Johnson 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 — 55.4% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
Deep Dive Reports
Detailed analysis for Johnson County, Illinois
Overview
Johnson County in Illinois covers 11 ZIP codes with an average Home Safety Score of C (64/100).
6 of 11 ZIP codes have recorded EPA violations. 12 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.