Public water system · IL1550010

Active

Oak Park Estates

At a glance

Oak Park Estates (PWSID IL1550010) is an active community water system in Putnam County, Illinois. It reports serving 185 people through 74 service connections. Its primary water source is purchased groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 7 are health-based, and the most recent began in October 2025.

Dataset updated October 2026 . Source: EPA SDWIS/ECHO public records.

Population served

185

Service connections

Primary source

GWP

Purchased groundwater

System type

CWS

Community water system

System record

PWSIDIL1550010

System typeCommunity water system

Activity statusActive

Population served185

Service connections74

Primary water sourcePurchased groundwater

Owner typePrivate

Primacy agencyIL state drinking water program

City served—

StateIllinois

ZIP—

CountyPutnam County

How does Oak Park Estates compare with other water systems in Putnam County?

By EPA's size categories, Oak Park Estates is a very small system (500 people or fewer). Putnam County has 20 active public water systems. Its population served is about 27% below the county average of 252 people per system, and accounts for 3.7% of the 5,039 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 Oak Park Estates 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 Oak Park Estates?

EPA lists Oak Park Estates 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. 11 of the 20 active systems in Putnam County (55%) are also privately owned.

Does Oak Park Estates have drinking water violations?

Of the 12 most recent violations in EPA's records, 7 are health-based, and the most recent began in October 2025. The violations listed here began between April 2004 and October 2025. By type: 7 contaminant level above the legal limit, 2 monitoring and reporting, 2 public notice, recordkeeping or other and 1 monitoring. The contaminant or rule involved most often is Combined Radium (-226 and -228) (5 of them). EPA lists 12 as resolved. 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
2025-10-01	MonitoringMonitoring, Routine (RTCR) · code 3A	Revised Total Coliform Rulecode 8000	No	Resolved
2025-10-01	Monitoring and reportingMonitoring and Reporting (DBP) · code 27	Chlorinecode 0999	No	Resolved
2017-12-30	Monitoring and reportingLead Consumer Notice · code 66	Lead and Copper Rulecode 5000	No	Resolved
2007-07-01	Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71	Consumer Confidence Rulecode 7000	No	Resolved
2005-04-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Combined Radium (-226 and -228)code 4010	Yes	Resolved
2005-04-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Gross alpha (excluding radon and uranium)code 4000	Yes	Resolved
2005-01-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Combined Radium (-226 and -228)code 4010	Yes	Resolved
2005-01-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Gross alpha (excluding radon and uranium)code 4000	Yes	Resolved
2004-10-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Combined Radium (-226 and -228)code 4010	Yes	Resolved
2004-07-01	Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72	Consumer Confidence Rulecode 7000	No	Resolved
2004-07-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Combined Radium (-226 and -228)code 4010	Yes	Resolved
2004-04-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Combined Radium (-226 and -228)code 4010	Yes	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.

Oak Park Estates: frequently asked questions

Who runs Oak Park Estates?

Oak Park Estates (PWSID IL1550010) is a community water system privately owned. It is regulated by the IL state drinking water program.

How many people does Oak Park Estates serve?

Oak Park Estates reports serving 185 people through 74 service connections in Putnam County, Illinois.

Where does Oak Park Estates 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 Oak Park Estates have any drinking water violations?

Of the 12 most recent violations in EPA's records, 7 are health-based, and the most recent began in October 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 Oak Park Estates' 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, 7 are health-based, and the most recent began in October 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 Oak Park Estates' water quality report?

As a community water system, Oak Park Estates 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 Putnam County

Water system	County	Population served	Type	Source
Granville	Putnam	1,359	Community	Groundwater
Hennepin PWD	Putnam	750	Community	Groundwater
Mark	Putnam	555	Community	Groundwater
Lake Thunderbird Subdivsion	Putnam	450	Community	Groundwater
Mcnabb	Putnam	258	Community	Groundwater
Magnolia	Putnam	244	Community	Groundwater

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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, “Oak Park Estates, PWSID IL1550010, Illinois”, https://aquacensus.com/water-systems/illinois/oak-park-estates-il1550010 (data as of October 1, 2026).