Public water system · OR4101560
ActiveKnoll Terrace Subdivision
At a glance
Knoll Terrace Subdivision (PWSID OR4101560) is an active community water system in Douglas County, Oregon. It reports serving 221 people through 134 service connections. Its primary water source is purchased surface water, and EPA lists it as privately owned. EPA's records list 3 violations for this system; none is health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
221
Service connections
134
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Knoll Terrace Subdivision compare with other water systems in Douglas County?
By EPA's size categories, Knoll Terrace Subdivision is a very small system (500 people or fewer). Douglas County has 102 active public water systems. Its population served is well below the county average of 916 people per system, and accounts for 0.2% of the 93,402 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 Knoll Terrace Subdivision 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. 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 Knoll Terrace Subdivision?
EPA lists Knoll Terrace Subdivision as privately owned. 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. 59 of the 102 active systems in Douglas County (58%) are also privately owned.
Does Knoll Terrace Subdivision have drinking water violations?
EPA's records list 3 violations for this system; none is health-based, and the most recent began in July 2025. The violations listed here began between May 2023 and July 2025. By type: 2 monitoring and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Revised Total Coliform Rule (2 of them). EPA lists 2 as resolved and 1 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. 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 |
|---|---|---|---|---|
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Unaddressed |
| 2023-06-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2023-05-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
All 3 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.
Knoll Terrace Subdivision: frequently asked questions
Who runs Knoll Terrace Subdivision?
Knoll Terrace Subdivision (PWSID OR4101560) is a community water system privately owned. It is regulated by the OR state drinking water program.
How many people does Knoll Terrace Subdivision serve?
Knoll Terrace Subdivision reports serving 221 people through 134 service connections in Douglas County, Oregon.
Where does Knoll Terrace Subdivision 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 Knoll Terrace Subdivision have any drinking water violations?
EPA's records list 3 violations for this system; none is health-based, and the most recent began in July 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 Knoll Terrace Subdivision'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 3 violations for this system; none is health-based, and the most recent began in July 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 Knoll Terrace Subdivision's water quality report?
As a community water system, Knoll Terrace Subdivision 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 Douglas County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Roseburg, City of | Douglas | 28,800 | Community | Surface water |
| Umpqua Basin Water Assoc | Douglas | 9,499 | Community | Surface water |
| Winston-Dillard Water District | Douglas | 8,300 | Community | Surface water |
| Sutherlin, City of | Douglas | 8,060 | Community | Surface water |
| Green Area Water & Sanitary Authority | Douglas | 7,000 | Community | Surface water |
| Reedsport, City of | Douglas | 4,836 | Community | 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, “Knoll Terrace Subdivision, PWSID OR4101560, Oregon”, https://aquacensus.com/water-systems/oregon/knoll-terrace-subdivision-or4101560 (data as of October 1, 2026).