Public water system · IL1970600
ActiveMokena
At a glance
Mokena (PWSID IL1970600) is an active community water system in Will County, Illinois. It reports serving 19,887 people through 7,250 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in July 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
19,887
Service connections
7,250
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Mokena compare with other water systems in Will County?
By EPA's size categories, Mokena is a large system (10,001 to 100,000 people). Will County has 236 active public water systems. Its population served is about 7.6 times the county average of 2,607 people per system, and accounts for 3.2% 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 Mokena is about 197% above 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 619 Illinois systems (16%) list purchased surface water as their primary source.
Who owns and regulates Mokena?
EPA lists Mokena 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 Mokena have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in July 2024. The violations listed here began between June 1977 and July 2024. By type: 8 monitoring and reporting, 2 contaminant level above the legal limit, 1 monitoring and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Total coliform bacteria (TCR) (5 of them). EPA lists 7 as resolved and 5 as archived. 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. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2024-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2024-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2021-03-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2021-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2018-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2012-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1996-06-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1996-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1996-03-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1993-04-01 | Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1992-11-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1977-06-30 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Archived |
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.
Mokena: frequently asked questions
Who runs Mokena?
Mokena (PWSID IL1970600) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does Mokena serve?
Mokena reports serving 19,887 people through 7,250 service connections in Will County, Illinois.
Where does Mokena get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Mokena have any drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in July 2024. 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 Mokena'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, 2 are health-based, and the most recent began in July 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.
Where can I find Mokena's water quality report?
As a community water system, Mokena 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, “Mokena, PWSID IL1970600, Illinois”, https://aquacensus.com/water-systems/illinois/mokena-il1970600 (data as of October 1, 2026).