Public water system · IL1971100
ActiveWilmington
At a glance
Wilmington (PWSID IL1971100) is an active community water system in Will County, Illinois. It reports serving 5,700 people through 2,471 service connections. Its primary water source is surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
5,700
Service connections
2,471
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does Wilmington compare with other water systems in Will County?
By EPA's size categories, Wilmington is a medium system (3,301 to 10,000 people). Will County has 236 active public water systems. Its population served is about twice the county average of 2,607 people per system, and accounts for 0.9% of the 615,219 people reported by systems filed under the county. Across Illinois, the 3,872 active systems average 3,204 people each. Nationally, the average active community water system reports serving 6,703 people, so Wilmington is about 15% below that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. Illinois has 1,773 active community water systems, 46% of the state's 3,872 active systems. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 89 Illinois systems (2.3%) list surface water as their primary source.
Who owns and regulates Wilmington?
EPA lists Wilmington as owned by a local government. The IL state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 34 of the 236 active systems in Will County (14%) are also owned by a local government.
Does Wilmington have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2025. The violations listed here began between January 2022 and July 2025. By type: 9 monitoring and reporting, 1 reporting, 1 monitoring and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Interim Enhanced Surface Water Treatment Rule (2 of them). EPA lists 11 as resolved and 1 as unaddressed. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2025-07-02 | ReportingNotification, Known or Potential LSL · code 4H | Lead and Copper Rule Revisionscode 5200 | No | Unaddressed |
| 2025-02-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloraminecode 1006 | No | Resolved |
| 2025-02-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-02-01 | Monitoring and reportingMonitoring, Turbidity (Enhanced SWTR) · code 38 | Interim Enhanced Surface Water Treatment Rulecode 0300 | No | Resolved |
| 2024-01-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2024-01-01 | Monitoring and reportingMonitoring, Turbidity (Enhanced SWTR) · code 38 | Interim Enhanced Surface Water Treatment Rulecode 0300 | No | Resolved |
| 2023-07-10 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2023-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2023-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Toxaphenecode 2020 | No | Resolved |
| 2022-12-30 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Carbon, totalcode 2920 | No | Resolved |
The 12 most recent violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Wilmington: frequently asked questions
Who runs Wilmington?
Wilmington (PWSID IL1971100) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does Wilmington serve?
Wilmington reports serving 5,700 people through 2,471 service connections in Will County, Illinois.
Where does Wilmington get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does Wilmington have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2025. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Wilmington's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.
Where can I find Wilmington's water quality report?
As a community water system, Wilmington must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Will County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Joliet | Will | 160,000 | Community | Groundwater |
| Il American-West Suburban | Will | 73,978 | Community | Purchased surface water |
| Romeoville | Will | 50,458 | Community | Groundwater |
| Plainfield | Will | 50,000 | Community | Purchased surface water |
| New Lenox | Will | 27,690 | Community | Purchased surface water |
| Il American-Homer Township | Will | 24,543 | Community | Purchased surface water |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Wilmington, PWSID IL1971100, Illinois”, https://aquacensus.com/water-systems/illinois/wilmington-il1971100 (data as of October 1, 2026).