Public water system · OR4100906
ActiveTualatin, City of
At a glance
City of Tualatin (PWSID OR4100906) is an active community water system in Washington County, Oregon. It reports serving 28,106 people through 7,400 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. EPA's records list 7 violations for this system; none is health-based, and the most recent began in June 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
28,106
Service connections
7,400
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does City of Tualatin compare with other water systems in Washington County?
By EPA's size categories, City of Tualatin is a large system (10,001 to 100,000 people). Washington County has 97 active public water systems, and City of Tualatin is the 5th-largest of them by population served. Its population served is about 4.6 times the county average of 6,158 people per system, and accounts for 4.7% of the 597,296 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 Tualatin is about 4.2 times 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 105 Oregon systems (4.1%) list purchased surface water as their primary source.
Who owns and regulates City of Tualatin?
EPA lists City of Tualatin 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. 26 of the 97 active systems in Washington County (27%) are also owned by a local government.
Does City of Tualatin have drinking water violations?
EPA's records list 7 violations for this system; none is health-based, and the most recent began in June 2024. The violations listed here began between August 2007 and June 2024. By type: 5 monitoring and reporting and 2 monitoring. The contaminant or rule involved most often is Revised Total Coliform Rule (2 of them). EPA lists 7 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 |
|---|---|---|---|---|
| 2024-06-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2019-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2019-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2019-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2017-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2007-08-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 7 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 Tualatin: frequently asked questions
Who runs City of Tualatin?
City of Tualatin (PWSID OR4100906) 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 Tualatin serve?
City of Tualatin reports serving 28,106 people through 7,400 service connections in Washington County, Oregon.
Where does City of Tualatin get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does City of Tualatin have any drinking water violations?
EPA's records list 7 violations for this system; none is health-based, and the most recent began in June 2024. 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 Tualatin'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. EPA's records list 7 violations for this system; none is health-based, and the most recent began in June 2024. 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 Tualatin's water quality report?
As a community water system, City of Tualatin 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 Washington County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Tualatin Valley Water District | Washington | 224,600 | Community | Purchased surface water |
| Hillsboro, City of | Washington | 92,632 | Community | Purchased surface water |
| Beaverton, City of | Washington | 88,045 | Community | Purchased surface water |
| Tigard, City of | Washington | 62,500 | Community | Purchased surface water |
| Forest Grove, City of | Washington | 26,838 | Community | Surface water |
| Sherwood, City of | Washington | 19,885 | Community | Purchased 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, “Tualatin, City of, PWSID OR4100906, Oregon”, https://aquacensus.com/water-systems/oregon/tualatin-city-of-or4100906 (data as of October 1, 2026).