Public water system · IA7561021
ActiveOyens Water Supply
At a glance
Oyens Water Supply (PWSID IA7561021) is an active community water system in Plymouth County, Iowa. It reports serving 92 people through 64 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, 9 are health-based, and the most recent began in July 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
92
Service connections
64
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Oyens Water Supply compare with other water systems in Plymouth County?
By EPA's size categories, Oyens Water Supply is a very small system (500 people or fewer). Plymouth County has 13 active public water systems. Its population served is well below the county average of 1,362 people per system, and accounts for 0.5% of the 17,703 people reported by systems filed under the county. Across Iowa, the 1,828 active systems average 1,718 people each. Nationally, the average active community water system reports serving 6,703 people, so Oyens Water Supply 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. Iowa has 1,084 active community water systems, 59% of the state's 1,828 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,502 Iowa systems (82%) list groundwater as their primary source.
Who owns and regulates Oyens Water Supply?
EPA lists Oyens Water Supply as owned by a local government. The IA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 10 of the 13 active systems in Plymouth County (77%) are also owned by a local government.
Does Oyens Water Supply have drinking water violations?
Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in July 2023. The violations listed here began between January 2002 and July 2023. By type: 9 contaminant level above the legal limit, 2 monitoring and reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Total coliform bacteria (TCR) (10 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 |
|---|---|---|---|---|
| 2023-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2012-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2012-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2011-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2011-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2010-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2009-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2008-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2007-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2007-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2004-08-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2002-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | 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.
Oyens Water Supply: frequently asked questions
Who runs Oyens Water Supply?
Oyens Water Supply (PWSID IA7561021) is a community water system owned by a local government. It is regulated by the IA state drinking water program.
How many people does Oyens Water Supply serve?
Oyens Water Supply reports serving 92 people through 64 service connections in Plymouth County, Iowa.
Where does Oyens Water Supply 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 Oyens Water Supply have any drinking water violations?
Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in July 2023. 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 Oyens Water Supply'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, 9 are health-based, and the most recent began in July 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the IA state drinking water program.
Where can I find Oyens Water Supply's water quality report?
As a community water system, Oyens Water Supply 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 Plymouth County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Lemars Water Department | Plymouth | 10,606 | Community | Groundwater |
| Remsen Municipal Utilities | Plymouth | 1,678 | Community | Groundwater |
| Akron, City of | Plymouth | 1,558 | Community | Groundwater |
| Kingsley Water Supply | Plymouth | 1,396 | Community | Groundwater |
| Hinton Water Supply | Plymouth | 935 | Community | Groundwater |
| Merrill Municipal Water Supply | Plymouth | 717 | 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, “Oyens Water Supply, PWSID IA7561021, Iowa”, https://aquacensus.com/water-systems/iowa/oyens-water-supply-ia7561021 (data as of October 1, 2026).