COUNTY REPORT IL

St. Clair County, Illinois

32 ZIP codes · Avg score 76/100 · Grade B · Updated

ZipCheckup grade for St. Clair County: B.

This ZIP looks solid, with a few items worth a quick check.

St. Clair County's tap water quality puts it in the upper tier nationally; the 32 ZIP codes here record few health-based violations.

How St. Clair County Compares

St. Clair County76/100
Illinois avg68/100
National avg73/100

How St. Clair County Compares

B
County Grade
76/100
Avg Safety Score
32
ZIP Codes
21
Water Systems

St. Clair County scores 8 points above the Illinois state average (68/100) and 3 points above the national average (73/100).

Data: ZipCheckup Home Safety Score model 4.0.0; EPA SDWIS, UCMR 5, EPA radon zones, EPA AirData Last verified:

B
County Grade
76
Avg Safety Score
32
ZIP Codes
Best ZIP: 62059 (83/100)
Lowest ZIP: 62258 (60/100)
$141K
Median Home Value
$1,797
Avg Remediation (127% of home value)

ZIP Code Risk Map

Water Quality Map: St. Clair County, Illinois

Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.

A B C D F

Key Risk Factors

Health risk index: 13.7 (asthma 11.1%, diabetes 13.1%)

Estimated additional annual cost per homeowner: $1,716, driven primarily by flood

64.7% of homes built before 1978 (lead paint era)

Violation History (2024–2025)

→ Stable trend

EPA violation counts by year across St. Clair County water systems. Health-based shown in red, total in blue.

2024
23 (23 health)
2025
4 (4 health)

Peak year: 2024 with 23 violations. Past 5 years: 27 total (27 health-based).

Source: EPA SDWIS historical violations. Data may lag 6–12 months for the most recent year.

County Health Indicators vs National Average

Asthma 11.1% (national: 8.9%)
Diabetes 13.1% (national: 10.5%)
Obesity 38.8% (national: 32.4%)

Black markers indicate national averages. Source: CDC PLACES, Census ACS.

Infrastructure Overview

1974
Median Build Year
64.7%
Pre-1978 Housing
44/100
Infrastructure Stress Indicator
63%
ZIPs with High Infrastructure Stress
High
Lead Pipe Risk

Modeled area-level indicator, not a failure probability. Sources: Census ACS housing age, EPA DWINS infrastructure needs, EPA SDWIS violations, and EPA lead indicators.

Compound Risk Breakdown

Estimated additional annual cost per homeowner: $1,716

Flood $1,261/yr
Energy Code Gap $466/yr
Water / Lead $211/yr

Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).

Housing Age Distribution

113,456 housing units in St. Clair County

Pre-1940 13%
1940–1959 20%
1960–1979 22%
1980–1999 24%
2000+ 21%

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. Clair County

$141K
Median Home Value
$1,797
Est. Remediation Cost
1.3%
of Home Value
Remediation as % of home value low burden

Remediation costs are relatively manageable for most homeowners in St. Clair 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. Clair County residents

Asthma 11.1% (US avg: 8.9%)
Diabetes 13.1% (US avg: 11%)
Obesity 38.8% (US avg: 32.4%)

Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.

Water systems serving St. Clair County

8 community water systems serving St. Clair County.

Show all 8 water systems
  • Columbia
    Serves ~11,129 people 2 violations
    C
  • Mascoutah
    Serves ~8,759 people 1 violation
    C

21 total water systems serve St. Clair County.

Systems with the most violations in St. Clair County

5 water systems with recorded EPA violations.

All ZIP Codes in St. Clair County

32 ZIP codes tracked in St. Clair County.

# ZIP Code City Safety Score Grade Violations Home Value
1 62059 Lovejoy 83 B 0 $37K
2 62205 East Saint Louis 83 B 0 $46K
3 62206 East Saint Louis 83 B 0 $58K
4 62207 East Saint Louis 83 B 0 $54K
5 62220 Belleville 83 B 1 $141K
6 62221 Belleville 83 B 2 $207K
7 62223 Belleville 83 B 3 $150K
8 62225 Scott Air Force Base 83 B 2
9 62226 Belleville 83 B 2 $163K
10 62254 Lebanon 83 B 5 $197K
11 62269 O Fallon 83 B 5 $274K
12 62001 Alhambra 80 B 8 (5 health) $209K
13 62255 Lenzburg 79 B 10 $153K
14 62257 Marissa 79 B 11 $119K
15 62285 Smithton 79 B 9 $265K
16 62264 New Athens 78 B 14 $137K
17 62201 East Saint Louis 68 C 14 (1 health) $56K
18 62203 East Saint Louis 68 C 16 (1 health) $73K
19 62204 East Saint Louis 68 C 14 (1 health) $48K
20 62208 Fairview Heights 68 C 16 (1 health) $168K
21 62232 Caseyville 68 C 16 (1 health) $115K
22 62260 Millstadt 66 C 2 $230K
23 62239 Dupo 65 C 3 $112K
24 62240 East Carondelet 65 C 3 $85K
25 62243 Freeburg 63 C 8 $268K
26 62258 Mascoutah 60 C 17 $230K
27 62071 National Stock Yards
28 62202 East Saint Louis
29 62222 Belleville
30 62224 Mascoutah
31 62282 Saint Libory $169K
32 62289 Summerfield $74K

Recommended Buyer Guides for St. Clair 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.

Overview

St. Clair County in Illinois covers 32 tracked ZIP records with an average Home Safety Score of B (76/100) across 26 scored records.

22 of 26 ZIP codes with a reported violation count in the available EPA record have recorded EPA violations. 6 health-based violations appear in the available health breakdown.

← Back to Illinois Home Safety Profile

Data Sources

Reporting periods vary by source. Missing data is shown as unavailable, not as zero.

Frequently Asked Questions

Is water safe in St. Clair County?
St. Clair County receives a grade of B, indicating generally safe tap water across its 32 ZIP codes.
How many water systems serve St. Clair County?
St. Clair County is served by 21 public water systems that supply drinking water to residents across 32 ZIP codes.
What is the biggest environmental risk in St. Clair County?
The primary environmental risk factor in St. Clair County is flood. This contributes to an estimated additional annual cost of $1,716 per homeowner.
How old are homes in St. Clair County?
The median home build year in St. Clair County is 1974. 64.7% of homes were built before 1978, which means they may contain lead-based paint and older plumbing materials.
How does St. Clair County compare to Illinois?
St. Clair County has an average Home Safety Score of 76/100 under model 4.0.0, which is above the Illinois state average of 68/100.

How to cite this page

APA ZipCheckup. (2026). St. Clair County, IL: HSS 76/100; 6 Health Violations. https://zipcheckup.com/county/illinois/st-clair/
BibTeX
@misc{zipcheckup-county-illinois-st-clair,
  author = {{ZipCheckup}},
  title  = {{St. Clair County, IL: HSS 76/100; 6 Health Violations}},
  year   = {2026},
  url    = {https://zipcheckup.com/county/illinois/st-clair/}
}

Page version: August 2026.

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