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South Wilmington, IL Tap Water Quality 2026

Water quality report for South Wilmington, IL — PFAS, lead and copper results, violation history and state inspection findings from EPA SDWIS.

A look at South Wilmington's drinking water using EPA enforcement records: violations, lead and copper results, PFAS sampling and state inspection findings.

Main Utility: South Wilmington PWSID: IL0630650 Updated: 2026 Q2
✅

No federal limits exceeded on record

Lead was not detected and no violations are open. PFAS has never been sampled at this system.

B

South Wilmington earns a B for water quality

Graded on violations and lead, with state inspection findings. PFAS not tested.

Lead: not detected
PFAS never sampled at this system
16 violations since 2015, 0 health-based
No violations currently open
South Wilmington's lead level vs. all Illinois community water systems
0 ppb5 ppb10 ppb15 ppb
Lead level: Not detected — 0% of the federal action level
✓ Lower lead than % of Illinois utilities
Population Served
669
~340 connections
Water Source
Groundwater
Drawn from wells — SDWIS source code GW
Active Violations
0
16 since 2015, all resolved

Lead & Copper Testing

Lead (Pb)
90th percentile of tap samples collected across the distribution system
0% of EPA action level
Not detected
Action level: 15 ppb
Lead was not detected at the 90th percentile — the result fell below the laboratory detection limit. That is not the same as an absence of lead in every tap, and older homes with lead service lines can still show higher readings.

Contaminant Violations (2015–Present)

ContaminantTypeMeasuredLimitPeriodStatus
Public Notice OTHER — — 2026 Unaddressed
Lead and Copper Rule MONITORING AND REPORTING — TT 2026 Unaddressed
LEAD AND COPPER RULE REVISIONS REPORTING FAILURE — — 2025 Unaddressed
Lead and Copper Rule MONITORING AND REPORTING — TT 2025 Unaddressed
Combined Uranium MONITORING AND REPORTING — 30 ug/L 2024 Resolved
Combined Uranium MONITORING AND REPORTING — 30 ug/L 2024 Resolved
Combined Radium (-226 and -228) MONITORING AND REPORTING — 5 pCi/L 2024 Resolved
Combined Uranium MONITORING AND REPORTING — 30 ug/L 2022 Resolved
Combined Radium (-226 and -228) MONITORING AND REPORTING — 5 pCi/L 2022 Resolved
Combined Uranium MONITORING AND REPORTING — 30 ug/L 2022 Resolved
Combined Radium (-226 and -228) MONITORING AND REPORTING — 5 pCi/L 2022 Resolved
Combined Radium (-226 and -228) MONITORING AND REPORTING — 5 pCi/L 2020 Resolved
Combined Radium (-226 and -228) MONITORING AND REPORTING — 5 pCi/L 2019 Resolved
Combined Radium (-226 and -228) MONITORING AND REPORTING — 5 pCi/L 2016 Resolved
TTHM MONITORING AND REPORTING — 0.080 mg/L 2015–2016 Resolved
Total Haloacetic Acids (HAA5) MONITORING AND REPORTING — 0.060 mg/L 2015–2016 Resolved
Understanding violation types MCL violations mean a contaminant exceeded the federal maximum limit — the most serious type.
TT (Treatment Technique) violations mean required treatment procedures weren't followed, but don't necessarily mean contamination occurred.

Violation History

16 violations are on record since 2015, of which 0 were health-based. All have been resolved and none remain open.

About the Main Water System

Utility South Wilmington
PWSID IL0630650
Water source Groundwater — Drawn from wells — SDWIS source code GW
Population served 669
Service connections 340
Systems serving this area 1
Regulator State primacy agency
Data through 2026 Q2 — EPA SDWIS

Frequently Asked Questions

Is South Wilmington tap water safe to drink? ▼
No federal limit is exceeded on record. No violations are currently open.
Does South Wilmington water have PFAS? ▼
This system has never been sampled for PFAS. EPA's national monitoring covered systems serving 3,300 people or more, so no results exist — which is not evidence that none is present.
Who supplies water to South Wilmington? ▼
South Wilmington (PWSID IL0630650). Groundwater. Drawn from wells — SDWIS source code GW
When was this system last inspected? ▼
It was last inspected on 2023-10-27. Inspectors recorded 3 significant deficiencies.

What Should South Wilmington Residents Do?

1
Read your annual water report
Your supplier publishes a Consumer Confidence Report each July covering the prior year.
2
Check for a lead service line
Lead reaches tap water mainly through service lines and household plumbing. Suppliers now publish an inventory identifying lead lines.
3
Flush before drinking
If water has sat in pipes more than six hours, run the cold tap for two minutes before drinking or cooking.

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