Public water system · OR4100826
ActiveSisters, City of
At a glance
City of Sisters (PWSID OR4100826) is an active community water system in Deschutes County, Oregon. It reports serving 3,778 people through 2,200 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, none is health-based, and the most recent began in August 2015.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
3,778
Service connections
2,200
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does City of Sisters compare with other water systems in Deschutes County?
By EPA's size categories, City of Sisters is a medium system (3,301 to 10,000 people). Deschutes County has 135 active public water systems, and City of Sisters is the 6th-largest of them by population served. Its population served is about 149% above the county average of 1,515 people per system, and accounts for 1.8% of the 204,467 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 Sisters is about 44% 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 Sisters?
EPA lists City of Sisters 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 135 active systems in Deschutes County (10%) are also owned by a local government.
Does City of Sisters have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in August 2015. The violations listed here began between January 2009 and August 2015. By type: 12 monitoring and reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (2 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 |
|---|---|---|---|---|
| 2015-08-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2013-03-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2012-01-01 | Monitoring and reportingFailure to Conduct Assessment Monitoring · code 19 | Coliphagecode 3028 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Picloramcode 2040 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) phthalatecode 2039 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Hexachlorobenzenecode 2274 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Trichloroethylenecode 2984 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Tetrachloroethylenecode 2987 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | trans-1,2-Dichloroethylenecode 2979 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Carbon tetrachloridecode 2982 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlorobenzenecode 2989 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) adipatecode 2035 | 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 Sisters: frequently asked questions
Who runs City of Sisters?
City of Sisters (PWSID OR4100826) 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 Sisters serve?
City of Sisters reports serving 3,778 people through 2,200 service connections in Deschutes County, Oregon.
Where does City of Sisters 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 Sisters 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 August 2015. 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 Sisters' 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 August 2015. 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 Sisters' water quality report?
As a community water system, City of Sisters 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 Deschutes County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Bend, City of | Deschutes | 77,704 | Community | Surface water |
| Redmond Water Department | Deschutes | 37,566 | Community | Groundwater |
| Avion Wc - Greater Avion | Deschutes | 35,332 | Community | Groundwater |
| Roats Water System | Deschutes | 6,469 | Community | Groundwater |
| Sunriver Water LLC/Sunriver Utilities | Deschutes | 4,300 | Community | Groundwater |
| Agate Water System | Deschutes | 3,153 | 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, “Sisters, City of, PWSID OR4100826, Oregon”, https://aquacensus.com/water-systems/oregon/sisters-city-of-or4100826 (data as of October 1, 2026).