Public water system · MI0003666
ActiveKnorrwood Knolls Subdivision
At a glance
Knorrwood Knolls Subdivision (PWSID MI0003666) is an active community water system in Oakland County, Michigan. It reports serving 240 people through 75 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list one violation for this system; it is health-based, and the most recent began in April 2016.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
240
Service connections
75
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Knorrwood Knolls Subdivision compare with other water systems in Oakland County?
By EPA's size categories, Knorrwood Knolls Subdivision is a very small system (500 people or fewer). Oakland County has 734 active public water systems. Its population served is well below the county average of 1,561 people per system, and accounts for less than 0.1% of the 1,145,905 people reported by systems filed under the county. Across Michigan, the 10,599 active systems average 847 people each. Nationally, the average active community water system reports serving 6,703 people, so Knorrwood Knolls Subdivision 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. Michigan has 1,332 active community water systems, 13% of the state's 10,599 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 10,214 Michigan systems (96%) list groundwater as their primary source.
Who owns and regulates Knorrwood Knolls Subdivision?
EPA lists Knorrwood Knolls Subdivision as owned by a local government. 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. 56 of the 734 active systems in Oakland County (7.6%) are also owned by a local government.
Does Knorrwood Knolls Subdivision have drinking water violations?
EPA's records list one violation for this system; it is health-based, and the most recent began in April 2016. By type: 1 required treatment not met. The contaminant or rule involved is Lead and Copper Rule. EPA lists 1 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 |
|---|---|---|---|---|
| 2016-04-01 | Required treatment not metOCCT/SOWT Study/Recommendation · code 57 | Lead and Copper Rulecode 5000 | Yes | Resolved |
The one violation in EPA's records. 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.
Knorrwood Knolls Subdivision: frequently asked questions
Who runs Knorrwood Knolls Subdivision?
Knorrwood Knolls Subdivision (PWSID MI0003666) is a community water system owned by a local government. It is regulated by the MI state drinking water program.
How many people does Knorrwood Knolls Subdivision serve?
Knorrwood Knolls Subdivision reports serving 240 people through 75 service connections in Oakland County, Michigan.
Where does Knorrwood Knolls Subdivision 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 Knorrwood Knolls Subdivision have any drinking water violations?
EPA's records list one violation for this system; it is health-based, and the most recent began in April 2016. 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 Knorrwood Knolls Subdivision'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 one violation for this system; it is health-based, and the most recent began in April 2016. For current results, consult the system's annual water quality report, EPA ECHO, or the MI state drinking water program.
Where can I find Knorrwood Knolls Subdivision's water quality report?
As a community water system, Knorrwood Knolls Subdivision 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 Oakland County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Troy | Oakland | 85,854 | Community | Purchased surface water |
| Rochester Hills | Oakland | 74,000 | Community | Purchased surface water |
| Waterford Township | Oakland | 73,441 | Community | Groundwater |
| Southfield | Oakland | 71,739 | Community | Purchased surface water |
| Pontiac | Oakland | 63,776 | Community | Purchased surface water |
| Royal Oak, City of | Oakland | 57,236 | 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, “Knorrwood Knolls Subdivision, PWSID MI0003666, Michigan”, https://aquacensus.com/water-systems/michigan/knorrwood-knolls-subdivision-mi0003666 (data as of October 1, 2026).