Public water system · MO4010434
ActiveKoshkonong Pws
At a glance
Koshkonong Pws (PWSID MO4010434) is an active community water system in Oregon County, Missouri. It reports serving 212 people through 104 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, 4 are health-based, and the most recent began in November 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
212
Service connections
104
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Koshkonong Pws compare with other water systems in Oregon County?
By EPA's size categories, Koshkonong Pws is a very small system (500 people or fewer). Oregon County has 7 active public water systems, and Koshkonong Pws is the 5th-largest of them by population served. Its population served is well below the county average of 678 people per system, and accounts for 4.5% of the 4,746 people reported by systems filed under the county. Across Missouri, the 2,943 active systems average 2,049 people each. Nationally, the average active community water system reports serving 6,703 people, so Koshkonong Pws 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. Missouri has 1,612 active community water systems, 55% of the state's 2,943 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 2,521 Missouri systems (86%) list groundwater as their primary source.
Who owns and regulates Koshkonong Pws?
EPA lists Koshkonong Pws as owned by a local government. The MO state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 6 of the 7 active systems in Oregon County (86%) are also owned by a local government.
Does Koshkonong Pws have drinking water violations?
Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in November 2023. The violations listed here began between October 1998 and November 2023. By type: 4 monitoring and reporting, 4 contaminant level above the legal limit, 3 public notice, recordkeeping or other and 1 monitoring. The contaminant or rule involved most often is Total coliform bacteria (TCR) (7 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 |
|---|---|---|---|---|
| 2023-11-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2020-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2012-01-01 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2006-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2005-11-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2005-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2005-05-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2002-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 1998-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1998-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1998-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1998-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | 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.
Koshkonong Pws: frequently asked questions
Who runs Koshkonong Pws?
Koshkonong Pws (PWSID MO4010434) is a community water system owned by a local government. It is regulated by the MO state drinking water program.
How many people does Koshkonong Pws serve?
Koshkonong Pws reports serving 212 people through 104 service connections in Oregon County, Missouri.
Where does Koshkonong Pws 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 Koshkonong Pws have any drinking water violations?
Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in November 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 Koshkonong Pws' 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, 4 are health-based, and the most recent began in November 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the MO state drinking water program.
Where can I find Koshkonong Pws' water quality report?
As a community water system, Koshkonong Pws 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 Oregon County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Thayer Pws | Oregon | 2,200 | Community | Groundwater |
| Alton Pws | Oregon | 1,000 | Community | Groundwater |
| Oregon County Pwsd 1 | Oregon | 900 | Community | Groundwater |
| Couch R 1 School | Oregon | 264 | Non-transient non-community | Groundwater |
| Oregon County Pwsd 2 | Oregon | 120 | Community | Groundwater |
| Usfs Greer Crossing | Oregon | 50 | 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, “Koshkonong Pws, PWSID MO4010434, Missouri”, https://aquacensus.com/water-systems/missouri/koshkonong-pws-mo4010434 (data as of October 1, 2026).