Public water system · OR4100935
ActiveWasco, City of
At a glance
City of Wasco (PWSID OR4100935) is an active community water system in Sherman County, Oregon. It reports serving 460 people through 215 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 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
460
Service connections
215
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does City of Wasco compare with other water systems in Sherman County?
By EPA's size categories, City of Wasco is a very small system (500 people or fewer). Sherman County has 12 active public water systems, and City of Wasco is the 2nd-largest of them by population served. Its population served is about 49% above the county average of 309 people per system, and accounts for 12% of the 3,709 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 Wasco 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 Wasco?
EPA lists City of Wasco 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. 6 of the 12 active systems in Sherman County (50%) are also owned by a local government.
Does City of Wasco 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 2025. The violations listed here began between January 2011 and October 2025. By type: 5 contaminant level above the legal limit, 4 monitoring and reporting, 2 public notice, recordkeeping or other and 1 monitoring. The contaminant or rule involved most often is Total coliform bacteria (TCR) (4 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 |
|---|---|---|---|---|
| 2025-10-22 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2025-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, E. coli (RTCR) · code 1A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2025-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2014-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2014-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2012-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2011-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2011-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Tetrachloroethylenecode 2987 | No | Resolved |
| 2011-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Xylenes, Totalcode 2955 | No | Resolved |
| 2011-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlorobenzenecode 2989 | No | Resolved |
| 2011-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloropropanecode 2983 | 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 Wasco: frequently asked questions
Who runs City of Wasco?
City of Wasco (PWSID OR4100935) 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 Wasco serve?
City of Wasco reports serving 460 people through 215 service connections in Sherman County, Oregon.
Where does City of Wasco 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 Wasco 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 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 City of Wasco'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 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 City of Wasco's water quality report?
As a community water system, City of Wasco 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 Sherman County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Biggs Service District | Sherman | 1,600 | Non-transient non-community | Groundwater |
| Moro, City of | Sherman | 350 | Community | Groundwater |
| Rufus Public Works | Sherman | 270 | Community | Groundwater |
| Sherman County School | Sherman | 240 | Non-transient non-community | Groundwater |
| Oprd Deschutes River Rec Area | Sherman | 200 | Transient non-community | Groundwater |
| Grass Valley Water System | Sherman | 184 | 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, “Wasco, City of, PWSID OR4100935, Oregon”, https://aquacensus.com/water-systems/oregon/wasco-city-of-or4100935 (data as of October 1, 2026).