Public water system · MI0040594
ActiveNorthfield Estates
At a glance
Northfield Estates (PWSID MI0040594) is an active community water system in Washtenaw County, Illinois. It reports serving 1,620 people through 648 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 2 violations for this system; none is health-based, and the most recent began in August 2019.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,620
Service connections
648
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Northfield Estates compare with other water systems in Washtenaw County?
By EPA's size categories, Northfield Estates is a small system (501 to 3,300 people). Washtenaw County has 1 active public water system, and Northfield Estates is the largest of them by population served. Its population served is roughly in line with the county average of 1,620 people per system, and accounts for 100% of the 1,620 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 Northfield 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. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 2,808 Illinois systems (73%) list groundwater as their primary source.
Who owns and regulates Northfield Estates?
EPA lists Northfield Estates as privately owned. The MI state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 1 of the 1 active systems in Washtenaw County (100%) are also privately owned.
Does Northfield Estates have drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in August 2019. The violations listed here began between August 2019 and August 2019. By type: 2 monitoring and reporting. The contaminants or rules involved are Haloacetic acids (HAA5) and Total trihalomethanes (TTHM). EPA lists 2 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 |
|---|---|---|---|---|
| 2019-08-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2019-08-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
All 2 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.
Northfield Estates: frequently asked questions
Who runs Northfield Estates?
Northfield Estates (PWSID MI0040594) is a community water system privately owned. It is regulated by the MI state drinking water program.
How many people does Northfield Estates serve?
Northfield Estates reports serving 1,620 people through 648 service connections in Washtenaw County, Illinois.
Where does Northfield Estates get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Northfield Estates have any drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in August 2019. 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 Northfield 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. EPA's records list 2 violations for this system; none is health-based, and the most recent began in August 2019. For current results, consult the system's annual water quality report, EPA ECHO, or the MI state drinking water program.
Where can I find Northfield Estates' water quality report?
As a community water system, Northfield 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.
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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, “Northfield Estates, PWSID MI0040594, Illinois”, https://aquacensus.com/water-systems/illinois/northfield-estates-mi0040594 (data as of October 1, 2026).