Public water system · OR4100998
ActiveDexter Oaks Co-Op
At a glance
Dexter Oaks Co-Op (PWSID OR4100998) is an active community water system in Lane County, Oregon. It reports serving 75 people through 38 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 7 are health-based, and the most recent began in October 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
75
Service connections
38
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Dexter Oaks Co-Op compare with other water systems in Lane County?
By EPA's size categories, Dexter Oaks Co-Op is a very small system (500 people or fewer). Lane County has 231 active public water systems. Its population served is well below the county average of 1,415 people per system, and accounts for less than 0.1% of the 326,858 people reported by systems filed under the county. Across Oregon, the 2,536 active systems average 1,587 people each. Nationally, the average active community water system reports serving 6,703 people, so Dexter Oaks Co-Op 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. Oregon has 940 active community water systems, 37% of the state's 2,536 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 2,175 Oregon systems (86%) list groundwater as their primary source.
Who owns and regulates Dexter Oaks Co-Op?
EPA lists Dexter Oaks Co-Op as privately owned. The OR state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 155 of the 231 active systems in Lane County (67%) are also privately owned.
Does Dexter Oaks Co-Op have drinking water violations?
Of the 12 most recent violations in EPA's records, 7 are health-based, and the most recent began in October 2025. The violations listed here began between July 2021 and October 2025. By type: 7 contaminant level above the legal limit, 3 public notice, recordkeeping or other and 2 monitoring and reporting. The contaminant or rule involved most often is Arsenic (8 of them). EPA lists 11 as resolved and 1 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2025-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Unaddressed |
| 2023-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2023-05-21 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2023-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Resolved |
| 2023-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2022-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2022-08-29 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2022-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2022-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2022-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2021-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2021-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | 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.
Dexter Oaks Co-Op: frequently asked questions
Who runs Dexter Oaks Co-Op?
Dexter Oaks Co-Op (PWSID OR4100998) is a community water system privately owned. It is regulated by the OR state drinking water program.
How many people does Dexter Oaks Co-Op serve?
Dexter Oaks Co-Op reports serving 75 people through 38 service connections in Lane County, Oregon.
Where does Dexter Oaks Co-Op 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 Dexter Oaks Co-Op have any drinking water violations?
Of the 12 most recent violations in EPA's records, 7 are health-based, and the most recent began in October 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 Dexter Oaks Co-Op'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, 7 are health-based, and the most recent began in October 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the OR state drinking water program.
Where can I find Dexter Oaks Co-Op's water quality report?
As a community water system, Dexter Oaks Co-Op 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 Lane County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Eugene Water & Electric Board | Lane | 176,000 | Community | Surface water |
| Springfield Utility Board | Lane | 62,100 | Community | Surface water |
| Cottage Grove, City of | Lane | 10,879 | Community | Surface water |
| Florence, City of | Lane | 9,561 | Community | Groundwater |
| Junction City Water Utilities | Lane | 7,000 | Community | Groundwater |
| Rainbow Water District | Lane | 6,300 | Community | Groundwater under influence of 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, “Dexter Oaks Co-Op, PWSID OR4100998, Oregon”, https://aquacensus.com/water-systems/oregon/dexter-oaks-co-op-or4100998 (data as of October 1, 2026).