Public water system · IL1115125
ActiveOakbrook Estates MHP
At a glance
Oakbrook Estates MHP (PWSID IL1115125) is an active community water system in McHenry County, Illinois. It reports serving 1,012 people through 405 service connections. Its primary water source is purchased groundwater, and EPA lists it as privately owned. EPA's records list 6 violations for this system; 1 is health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,012
Service connections
405
Primary source
GWP
Purchased groundwater
System type
CWS
Community water system
System record
How does Oakbrook Estates MHP compare with other water systems in McHenry County?
By EPA's size categories, Oakbrook Estates MHP is a small system (501 to 3,300 people). McHenry County has 192 active public water systems. Its population served is about 24% below the county average of 1,331 people per system, and accounts for 0.4% of the 255,516 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 Oakbrook Estates MHP is well 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. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own. 348 Illinois systems (9%) list purchased groundwater as their primary source.
Who owns and regulates Oakbrook Estates MHP?
EPA lists Oakbrook Estates MHP as privately owned. 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. 154 of the 192 active systems in McHenry County (80%) are also privately owned.
Does Oakbrook Estates MHP have drinking water violations?
EPA's records list 6 violations for this system; 1 is health-based, and the most recent began in July 2025. The violations listed here began between August 1993 and July 2025. By type: 3 monitoring and reporting, 2 reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (4 of them). EPA lists 4 as archived, 1 as unaddressed and 1 as resolved. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement. 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.
| 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 |
| 2024-10-17 | ReportingLSL Reporting · code 4G | Lead and Copper Rule Revisionscode 5200 | No | Resolved |
| 1994-04-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1993-09-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1993-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1993-08-01 | Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26 | Total coliform bacteria (TCR)code 3100 | No | Archived |
All 6 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.
Oakbrook Estates MHP: frequently asked questions
Who runs Oakbrook Estates MHP?
Oakbrook Estates MHP (PWSID IL1115125) is a community water system privately owned. It is regulated by the IL state drinking water program.
How many people does Oakbrook Estates MHP serve?
Oakbrook Estates MHP reports serving 1,012 people through 405 service connections in McHenry County, Illinois.
Where does Oakbrook Estates MHP get its water?
EPA SDWIS lists this system's primary water source as purchased groundwater. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own.
Does Oakbrook Estates MHP have any drinking water violations?
EPA's records list 6 violations for this system; 1 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 Oakbrook Estates MHP'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. EPA's records list 6 violations for this system; 1 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 Oakbrook Estates MHP's water quality report?
As a community water system, Oakbrook Estates MHP 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 McHenry County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Crystal Lake | McHenry | 40,661 | Community | Groundwater |
| Algonquin | McHenry | 30,700 | Community | Groundwater |
| Lake in the Hills | McHenry | 28,661 | Community | Groundwater |
| Huntley | McHenry | 28,495 | Community | Groundwater |
| Woodstock | McHenry | 25,630 | Community | Groundwater |
| Mchenry | McHenry | 22,335 | Community | Groundwater |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Oakbrook Estates MHP, PWSID IL1115125, Illinois”, https://aquacensus.com/water-systems/illinois/oakbrook-estates-mhp-il1115125 (data as of October 1, 2026).