Public water system · OR4105290
ActiveMt Shadow MHP
At a glance
Mt Shadow MHP (PWSID OR4105290) is an active community water system in Clackamas County, Oregon. It reports serving 30 people through 24 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 8 violations for this system; none is health-based, and the most recent began in August 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
30
Service connections
24
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Mt Shadow MHP compare with other water systems in Clackamas County?
By EPA's size categories, Mt Shadow MHP is a very small system (500 people or fewer). Clackamas County has 241 active public water systems. Its population served is well below the county average of 1,602 people per system, and accounts for less than 0.1% of the 385,972 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 Mt Shadow MHP 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 Mt Shadow MHP?
EPA lists Mt Shadow MHP 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. 155 of the 241 active systems in Clackamas County (64%) are also privately owned.
Does Mt Shadow MHP have drinking water violations?
EPA's records list 8 violations for this system; none is health-based, and the most recent began in August 2025. The violations listed here began between January 2019 and August 2025. By type: 4 monitoring and 4 monitoring and reporting. The contaminant or rule involved most often is Revised Total Coliform Rule (4 of them). EPA lists 8 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 |
|---|---|---|---|---|
| 2025-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2025-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Resolved |
| 2025-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Resolved |
| 2025-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Uraniumcode 4006 | No | Resolved |
| 2024-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2019-04-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2019-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
All 8 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.
Mt Shadow MHP: frequently asked questions
Who runs Mt Shadow MHP?
Mt Shadow MHP (PWSID OR4105290) is a community water system privately owned. It is regulated by the OR state drinking water program.
How many people does Mt Shadow MHP serve?
Mt Shadow MHP reports serving 30 people through 24 service connections in Clackamas County, Oregon.
Where does Mt Shadow MHP 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 Mt Shadow MHP have any drinking water violations?
EPA's records list 8 violations for this system; none is health-based, and the most recent began in August 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 Mt Shadow MHP'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 8 violations for this system; none is health-based, and the most recent began in August 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 Mt Shadow MHP's water quality report?
As a community water system, Mt Shadow MHP 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 Clackamas County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Sunrise Water Authority | Clackamas | 50,003 | Community | Purchased surface water |
| Lake Oswego Municipal Water | Clackamas | 40,000 | Community | Purchased surface water |
| Oregon City | Clackamas | 33,940 | Community | Purchased surface water |
| Oak Lodge Water Services | Clackamas | 30,000 | Community | Purchased surface water |
| Clackamas River Water | Clackamas | 29,918 | Community | Surface water |
| West Linn, City of | Clackamas | 28,000 | 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, “Mt Shadow MHP, PWSID OR4105290, Oregon”, https://aquacensus.com/water-systems/oregon/mt-shadow-mhp-or4105290 (data as of October 1, 2026).