Public water system · WA5355335
ActiveMission Ridge Ski Area Water System
At a glance
Mission Ridge Ski Area Water System (PWSID WA5355335) is an active transient non-community water system in Chelan County, Washington. It reports serving 1,009 people through 5 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 10 violations for this system; 4 are health-based, and the most recent began in November 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,009
Service connections
5
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Mission Ridge Ski Area Water System compare with other water systems in Chelan County?
By EPA's size categories, Mission Ridge Ski Area Water System is a small system (501 to 3,300 people). Chelan County has 131 active public water systems. Its population served is roughly in line with the county average of 931 people per system, and accounts for 0.8% of the 121,966 people reported by systems filed under the county. Across Washington, the 4,705 active systems average 2,172 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Mission Ridge Ski Area Water System is about 7 times that figure.
What does “transient non-community water system” mean?
A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. Washington has 1,913 active transient non-community water systems, 41% of the state's 4,705 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 4,370 Washington systems (93%) list groundwater as their primary source.
Who owns and regulates Mission Ridge Ski Area Water System?
EPA lists Mission Ridge Ski Area Water System as privately owned. The WA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 100 of the 131 active systems in Chelan County (76%) are also privately owned.
Does Mission Ridge Ski Area Water System have drinking water violations?
EPA's records list 10 violations for this system; 4 are health-based, and the most recent began in November 2023. The violations listed here began between April 1992 and November 2023. By type: 3 monitoring, 3 monitoring and reporting, 2 contaminant level above the legal limit and 2 required treatment not met. The contaminant or rule involved most often is Revised Total Coliform Rule (4 of them). EPA lists 6 as archived and 4 as resolved. 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. 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 |
|---|---|---|---|---|
| 2023-11-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2022-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2018-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, E. coli (RTCR) · code 1A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 1999-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1998-12-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1998-05-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Archived |
| 1998-04-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Archived |
| 1996-04-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1992-04-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Archived |
All 10 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.
Mission Ridge Ski Area Water System: frequently asked questions
Who runs Mission Ridge Ski Area Water System?
Mission Ridge Ski Area Water System (PWSID WA5355335) is a transient non-community water system privately owned. It is regulated by the WA state drinking water program.
How many people does Mission Ridge Ski Area Water System serve?
Mission Ridge Ski Area Water System reports serving 1,009 people through 5 service connections in Chelan County, Washington.
Where does Mission Ridge Ski Area Water System 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 Mission Ridge Ski Area Water System have any drinking water violations?
EPA's records list 10 violations for this system; 4 are health-based, and the most recent began in November 2023. 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 Mission Ridge Ski Area Water System'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 10 violations for this system; 4 are health-based, and the most recent began in November 2023. For current results, consult EPA ECHO, or the WA state drinking water program.
Where can I find Mission Ridge Ski Area Water System's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Mission Ridge Ski Area Water System is a transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Chelan County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Wenatchee City of | Chelan | 43,690 | Community | Groundwater |
| Chelan Co PUD 1 | Chelan | 16,190 | Community | Purchased groundwater |
| Leavenworth City of | Chelan | 11,041 | Community | Surface water |
| Chelan Water Dept City of | Chelan | 9,425 | Community | Surface water |
| Lake Chelan Reclamation District | Chelan | 6,798 | Community | Surface water |
| Cashmere Water Department | Chelan | 5,815 | 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, “Mission Ridge Ski Area Water System, PWSID WA5355335, Washington”, https://aquacensus.com/water-systems/washington/mission-ridge-ski-area-water-system-wa5355335 (data as of October 1, 2026).