Public water system · MI0005260
ActivePentwater
At a glance
Pentwater (PWSID MI0005260) is an active community water system in Oceana County, Michigan. It reports serving 857 people through 715 service connections. Its primary water source is groundwater, 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 January 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
857
Service connections
715
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Pentwater compare with other water systems in Oceana County?
By EPA's size categories, Pentwater is a small system (501 to 3,300 people). Oceana County has 129 active public water systems, and Pentwater is the 5th-largest of them by population served. Its population served is about 3.6 times the county average of 236 people per system, and accounts for 2.8% of the 30,487 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 Pentwater 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 Pentwater?
EPA lists Pentwater 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. 3 of the 129 active systems in Oceana County (2.3%) are also owned by a local government.
Does Pentwater have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in January 2025. The violations listed here began between May 1993 and January 2025. By type: 7 monitoring and reporting, 3 public notice, recordkeeping or other and 2 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (5 of them). EPA lists 10 as resolved and 2 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 |
|---|---|---|---|---|
| 2025-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Archived |
| 2025-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Archived |
| 2024-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2022-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2006-09-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2006-07-01 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2006-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2006-01-23 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2003-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1996-01-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1993-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1993-05-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | 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.
Pentwater: frequently asked questions
Who runs Pentwater?
Pentwater (PWSID MI0005260) is a community water system owned by a local government. It is regulated by the MI state drinking water program.
How many people does Pentwater serve?
Pentwater reports serving 857 people through 715 service connections in Oceana County, Michigan.
Where does Pentwater 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 Pentwater 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 January 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 Pentwater'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 January 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the MI state drinking water program.
Where can I find Pentwater's water quality report?
As a community water system, Pentwater 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 Oceana County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Hart | Oceana | 2,126 | Community | Groundwater |
| Shelby | Oceana | 1,964 | Community | Groundwater |
| Gateway Plaza Hart | Oceana | 1,103 | Non-transient non-community | Groundwater |
| Rothbury Wesco - Store #51 | Oceana | 900 | Transient non-community | Groundwater |
| Wishing Well Ez Mart #899 | Oceana | 850 | Transient non-community | Groundwater |
| Silver Lake Resort & Campground | Oceana | 800 | Transient non-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, “Pentwater, PWSID MI0005260, Michigan”, https://aquacensus.com/water-systems/michigan/pentwater-mi0005260 (data as of October 1, 2026).