F0/100

WILMINGTON — Water Quality Report 2026

Serving 5,624 people · Illinois

Water Source

Surface Water

County

—

System ID

IL1971100

Violations

104

Contaminant Test Results

1 contaminant above EPA health goals

Contaminant	Detected	Limit (MCL)	Goal (MCLG)	Status
Lead (90th percentile)	0.002 mg/L	0.015 mg/L	0 mg/L	Above Goal

EPA Violation History

Violations (last 5yr)

Unresolved

Health-Related

TIER 3Unresolved

Reporting Violation

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: July 2, 2025Rule: Ground Water RuleEnforcement: Informal — resolved cooperativelyVerify on EPA.gov

TIER 3Resolved

Monitoring Violation

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: February 1, 2025 – February 28, 2025Rule: Total Coliform RuleEnforcement: Resolving — corrective action underway

TIER 3Resolved

Failed Level 2 Assessment under Revised Total Coliform Rule

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: February 1, 2025 – February 28, 2025Rule: Stage 1 DBPREnforcement: Resolving — corrective action underway

TIER 3Resolved

Missed required monitoring deadline

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: February 1, 2024 – February 29, 2024Rule: Surface Water Treatment RuleEnforcement: Resolving — corrective action underway

TIER 3Resolved

Missed required monitoring deadline

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – January 31, 2024Rule: Surface Water Treatment RuleEnforcement: Resolving — corrective action underway

TIER 3Resolved

Failed to complete routine monitoring

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – January 31, 2024Rule: Surface Water Treatment RuleEnforcement: Resolving — corrective action underway

TIER 3Resolved

Surface water treatment technique failure

When: July 10, 2023 – May 15, 2024Enforcement: Resolving — corrective action underway

TIER 3Resolved

Failed Level 2 Assessment under Revised Total Coliform Rule

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: April 1, 2023 – June 30, 2023Rule: Stage 2 DBPREnforcement: Resolving — corrective action underway

TIER 3Resolved

Failed Level 2 Assessment under Revised Total Coliform Rule

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: April 1, 2023 – June 30, 2023Rule: Stage 2 DBPREnforcement: Resolving — corrective action underway

TIER 3Resolved

Monitoring / Reporting Violation

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: December 30, 2022 – January 5, 2023Rule: Ground Water RuleEnforcement: Resolving — corrective action underway

TIER 3Resolved

Failed Level 2 Assessment under Revised Total Coliform Rule

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2022 – March 31, 2022Rule: Stage 1 DBPREnforcement: Resolving — corrective action underway

Understanding violation severity

Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.

Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly

Frequently Asked Questions About WILMINGTON

Is WILMINGTON water safe to drink?

WILMINGTON water receives a grade of F (0/100), which is considered failing. 0 contaminant(s) exceed EPA legal limits and 104 violation(s) are on record. Customers may want to consider using a water filter.

What contaminants has WILMINGTON detected?

31 contaminants were tested in WILMINGTON's water. Notable contaminants include Lead (90th percentile). No contaminants exceed EPA legal limits. 1 exceed EPA health goals (MCLGs).

Does WILMINGTON have any EPA violations?

Yes, WILMINGTON has 104 EPA violation(s) on record, with the most recent in 2025. Violation types include RPT, MON, MR. 8 are health-based violations.

How many people does WILMINGTON serve?

WILMINGTON serves approximately 5,624 people, Illinois. The system provides water to 1 community: Wilmington.

What type of water does WILMINGTON provide?

WILMINGTON sources its water from surface water. Surface water comes from rivers, lakes, or reservoirs and typically requires more extensive treatment. The utility's system ID is IL1971100.

How does WILMINGTON compare to other utilities in Illinois?

WILMINGTON scores 0/100 with a grade of F (failing). This score suggests significant water quality concerns relative to other utilities. Visit our Illinois state page for a full comparison of water systems.

Cities Served

Wilmington