Public water system · OR4100915

Active

Union, City of

At a glance

City of Union (PWSID OR4100915) is an active community water system in Union County, Oregon. It reports serving 2,162 people through 958 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, 5 are health-based, and the most recent began in October 2023.

Dataset updated October 2026 . Source: EPA SDWIS/ECHO public records.

Population served

2,162

Service connections

958

Primary source

Groundwater

System type

CWS

Community water system

System record

PWSIDOR4100915

System typeCommunity water system

Activity statusActive

Population served2,162

Service connections958

Primary water sourceGroundwater

Owner typeLocal government

Primacy agencyOR state drinking water program

City served—

StateOregon

ZIP—

CountyUnion County

How does City of Union compare with other water systems in Union County?

By EPA's size categories, City of Union is a small system (501 to 3,300 people). Union County has 20 active public water systems, and City of Union is the 2nd-largest of them by population served. Its population served is about twice the county average of 1,040 people per system, and accounts for 10% of the 20,797 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 City of Union 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 City of Union?

EPA lists City of Union as owned by a local government. 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. 7 of the 20 active systems in Union County (35%) are also owned by a local government.

Does City of Union have drinking water violations?

Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in October 2023. The violations listed here began between April 1997 and October 2023. By type: 5 contaminant level above the legal limit, 3 public notice, recordkeeping or other, 3 monitoring and reporting and 1 monitoring. The contaminant or rule involved most often is Total coliform bacteria (TCR) (6 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
2023-10-01	Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72	Consumer Confidence Rulecode 7000	No	Resolved
2023-07-01	Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71	Consumer Confidence Rulecode 7000	No	Resolved
2020-06-01	MonitoringMonitoring, Routine (RTCR) · code 3A	Revised Total Coliform Rulecode 8000	No	Resolved
2015-09-18	Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75	Public Noticecode 7500	No	Resolved
2015-07-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Resolved
2011-03-01	Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24	Total coliform bacteria (TCR)code 3100	No	Resolved
2002-01-01	Monitoring and reportingMonitoring, Regular · code 03	Nitratecode 1040	No	Resolved
2000-01-01	Monitoring and reportingMonitoring, Regular · code 03	Nitratecode 1040	No	Resolved
1999-06-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21	Total coliform bacteria (TCR)code 3100	Yes	Resolved
1999-06-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Resolved
1997-04-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Resolved
1997-04-01	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.

City of Union: frequently asked questions

Who runs City of Union?

City of Union (PWSID OR4100915) is a community water system owned by a local government. It is regulated by the OR state drinking water program.

How many people does City of Union serve?

City of Union reports serving 2,162 people through 958 service connections in Union County, Oregon.

Where does City of Union 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 City of Union have any drinking water violations?

Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in October 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 City of Union'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, 5 are health-based, and the most recent began in October 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the OR state drinking water program.

Where can I find City of Union's water quality report?

As a community water system, City of Union 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 Union County

Water system	County	Population served	Type	Source
La Grande, City of	Union	13,460	Community	Groundwater
Elgin Water Department	Union	1,717	Community	Groundwater
Island City	Union	1,166	Community	Groundwater
Cove, City of	Union	550	Community	Groundwater
North Powder, City of	Union	501	Community	Groundwater
Imbler, City of	Union	250	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, “Union, City of, PWSID OR4100915, Oregon”, https://aquacensus.com/water-systems/oregon/union-city-of-or4100915 (data as of October 1, 2026).