Public water system · OR4100869
ActiveThe Dalles, City of
At a glance
City of The Dalles (PWSID OR4100869) is an active community water system in Wasco County, Oregon. It reports serving 13,010 people through 5,408 service connections. Its primary water source is surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
13,010
Service connections
5,408
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does City of The Dalles compare with other water systems in Wasco County?
By EPA's size categories, City of The Dalles is a large system (10,001 to 100,000 people). Wasco County has 44 active public water systems, and City of The Dalles is the largest of them by population served. Its population served is about 22 times the county average of 583 people per system, and accounts for 51% of the 25,664 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 The Dalles is about twice 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. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 211 Oregon systems (8.3%) list surface water as their primary source.
Who owns and regulates City of The Dalles?
EPA lists City of The Dalles 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. 14 of the 44 active systems in Wasco County (32%) are also owned by a local government.
Does City of The Dalles have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2026. The violations listed here began between July 2023 and January 2026. By type: 12 monitoring and reporting. The contaminant or rule involved most often is Lead and Copper Rule (5 of them). EPA lists 7 as resolved, 3 as archived and 2 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. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status. 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 |
|---|---|---|---|---|
| 2026-01-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Unaddressed |
| 2026-01-01 | Monitoring and reportingInitial, Follow-up, or Routine Source Water M/R · code 56 | Lead and Copper Rulecode 5000 | No | Unaddressed |
| 2025-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Uraniumcode 4006 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Archived |
| 2023-07-01 | Monitoring and reportingInitial, Follow-up, or Routine Source Water M/R · code 56 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2023-07-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2023-07-01 | Monitoring and reportingInitial, Follow-up, or Routine Source Water M/R · code 56 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2023-07-01 | Monitoring and reportingMonitoring, Turbidity (Enhanced SWTR) · code 38 | Interim Enhanced Surface Water Treatment Rulecode 0300 | No | Resolved |
| 2023-07-01 | Monitoring and reportingInitial, Follow-up, or Routine Source Water M/R · code 56 | Lead and Copper Rulecode 5000 | 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.
City of The Dalles: frequently asked questions
Who runs City of The Dalles?
City of The Dalles (PWSID OR4100869) 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 The Dalles serve?
City of The Dalles reports serving 13,010 people through 5,408 service connections in Wasco County, Oregon.
Where does City of The Dalles get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does City of The Dalles have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2026. 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 The Dalles' 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, none is health-based, and the most recent began in January 2026. 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 The Dalles' water quality report?
As a community water system, City of The Dalles 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 Wasco County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Chenowith PUD | Wasco | 4,500 | Community | Groundwater |
| Barlow Water District | Wasco | 900 | Community | Groundwater |
| Ote Memaloose Rest Area | Wasco | 800 | Transient non-community | Groundwater |
| Dufur, City of | Wasco | 610 | Community | Groundwater |
| Young Life | Wasco | 497 | Community | Surface water |
| Mosier, City of | Wasco | 468 | 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, “The Dalles, City of, PWSID OR4100869, Oregon”, https://aquacensus.com/water-systems/oregon/the-dalles-city-of-or4100869 (data as of October 1, 2026).