WaterVerge

Is Wilsonville, IL Tap Water Safe to Drink?

Graded A-, with 6 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

536 residents served 1 water system PWSID: IL1171200
Overall Score
87.1 / 100
Violations
6 active
Last Updated
May 2026
Source
Purchased surface water
#288 of 891 in Illinois Top 27% nationally
Local Government
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
A-GRADE
Water Quality Grade
87.1/100
waterverge.com
A- 87.1/100

Wilsonville, IL — Water Quality Report

Wilsonville's drinking water received a grade of A- (87.1 out of 100), indicating good water quality. The city's 1 water system serves approximately 536 residents using purchased surface water.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.

The system has 31 violations on record, including 6 health-based violations. 6 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Wilsonville's water

Wilsonville ranks #288 out of 891 cities in Illinois for water quality, placing it mid-range in the state.

The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.

As a small community water system, Wilsonville may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

Quality Breakdown

Water quality score

See methodology →
87.1 out of 100 Grade A-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
38.1/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.0 ppb (90th percentile).
Contaminants
17/20
B
PFAS + legacy contaminant analysis.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Purchased surface water.
Water Safety

Is Wilsonville, IL water safe to drink?

Concerns Identified

Wilsonville's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (87.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 536 residents using surface water (rivers, lakes, or reservoirs).

6
Active Violations
0.0 ppb
Lead (90th %ile)
1 event
Disaster History

Recent water quality updates for Wilsonville

A timeline of significant water quality events, violations, and data updates.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Wilsonville's water quality assessment. Grade: A- (87.1/100).

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Violation
1 drinking water violation recorded

Contaminants: Total Haloacetic Acids (HAA5).

Violation
2 drinking water violations recorded

Contaminants: Total Haloacetic Acids (HAA5), TTHM.

Disaster
HURRICANE KATRINA EVACUATION

Federal disaster declaration (FEMA DR-3230). Hurricane event — may have impacted local water infrastructure.

Key contaminant findings

Based on the most recent EPA sampling data for Wilsonville's water supply.

Lead Within Limits
Detected: 0.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

Wilsonville's water system has 31 total violations on record, including 6 health-based violations. 6 remain unresolved. 4 violations were issued in the last 5 years.

OtherMRMCL
Most recent violations:
Jul 2025 Consumer Confidence Rule Open
Oct 2024 Total Haloacetic Acids (HAA5) Resolved
Jul 2024 Total Haloacetic Acids (HAA5) Resolved
Jul 2024 TTHM Resolved
Dec 2020 Lead and Copper Rule Open

Flood & environmental risk

Macoupin County has experienced 1 federally declared disaster since 2005. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies.

HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3230

Where does Wilsonville's water come from?

Wilsonville's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 536 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment.

What Wilsonville residents can do

Install a water filter

Recommended: NSF-certified water filter. This addresses the specific contaminants found in Wilsonville's water.

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
0.0 ppb
EPA Action Level: 15 ppb · 0% of limit
Safe Level
Compliance Record

Violation summary

31
Total violations
6
Health-based
6
Active / unresolved
Jul 2025
Most recent violation
Compliance Record

Violations & advisories

31 Total
6 Active
6 Health-based
25 Resolved
Violations by category
Total Coliform Rule
13
Synthetic Organic Chemicals
6
Lead and Copper Rule
4
Stage 2 Disinfectants and Disinfection Byproducts Rule
3
Stage 1 Disinfectants and Disinfection Byproducts Rule
3
Jul 2025 Active
Consumer Confidence Rule
Other Violation 0
Dec 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2019 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 1994 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Apr 1993 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Oct 2024 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jul 2024 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Jul 2024 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Dec 2015 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2015
Oct 2015 Resolved
Chloramine
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2015
Jan 2005 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2005
Jan 2005 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2005
Jun 2001 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2001
Jul 1997 Resolved
Atrazine
Max Contaminant Level
Health-Based Health Resolved Sep 1997
Apr 1997 Resolved
Atrazine
Max Contaminant Level
Health-Based Health Resolved Jun 1997
Jan 1997 Resolved
Atrazine
Max Contaminant Level
Health-Based Health Resolved Mar 1997
Nov 1996 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 1996
Oct 1996 Resolved
Atrazine
Max Contaminant Level
Health-Based Health Resolved Dec 1996
Jul 1996 Resolved
Atrazine
Max Contaminant Level
Health-Based Health Resolved Sep 1996
Showing 20 of 31 violations
Industrial pollution

Top industrial polluters within 10 miles of Wilsonville

Industrial polluters nearby

Reported releases to surface water by facilities near Wilsonville, ranked by pounds discharged annually.

FacilityTop chemicalTo surface water (lbs/yr)Distance
MENNEL MILLING CO OF ILLINOIS
Food · THE MENNEL MILLING CO
MOUNT OLIVE, IL62069
7.1 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Flood & disaster history

1
Declared disasters
Sep 2005
Most recent
Hurricane
Most common type

Macoupin County has experienced 1 federally declared disaster since 2005. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3230

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 0.0 ppb from 1994 (0.0 ppb) to 2025 (0.0 ppb).
Contaminant Rankings

See how Wilsonville compares by contaminant

Explore where Wilsonville ranks among all Illinois cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Purchased Surface Water
Operator
Local Government
Population Served
536
Water Systems
1
Water Source

Where Wilsonville's water comes from

Purchased Surface Water

Wilsonville's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.

These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.

The system is operated by local government ownership and serves approximately 536 people through 1 water system.

Infrastructure

Water systems serving Wilsonville

System Name PWSID Population Source
WILSONVILLE IL1171200 536 SWP
Regional Comparison

How Wilsonville compares

Full Illinois rankings →

Wilsonville's score of 87.1/100 is above the average of 56/100 among major Illinois cities. It outscores 9 of 10 nearby cities.

Wilsonville (this city)
87.1
Chicago
35.2
Aurora
45.5
Joliet
38.5
Naperville
81.2
Champaign
91.9
Illinois avg
56
City Profile

About Wilsonville, IL

Wikipedia →

Wilsonville is a village in Macoupin County, Illinois, United States. The population was 536 at the 2020 census.

Economic Profile
$56,250
Median Income
$74,097
Median Home Value
$795/mo
Median Rent
3.2%
Unemployment
Community
40.6
Median Age
210
People / sq mi
5.5%
College Educated
75.8%
Homeownership
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Frequently asked questions

Is Wilsonville, IL tap water safe to drink?

Wilsonville's water quality earned a grade of A- (87.1/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #288 out of 891 cities tested in Illinois.

What contaminants are in Wilsonville's water?

Lead was measured at 0.0 ppb (90th percentile). 31 violations are on record.

How is Wilsonville's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Wilsonville?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Wilsonville's water come from?

Wilsonville's water is sourced from Purchased surface water. The city has 1 water system serving approximately 536 residents.

What health violations has Wilsonville's water system had?

Wilsonville has 6 health-based violations on record. The most recent violation was recorded in July 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 6 violations remain unresolved.

How does Wilsonville's water compare to other cities?

Wilsonville ranks #288 out of 891 cities in Illinois (better than 68% of state cities) and #4279 out of 15744 cities nationally (73th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Does Wilsonville's small water system affect quality?

Wilsonville's system serves approximately 536 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 31 violations on record.