Public water system · WA5304316
ActiveCowiche Water Association
At a glance
Cowiche Water Association (PWSID WA5304316) is an active community water system in Yakima County, Washington. It reports serving 48 people through 18 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
48
Service connections
18
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Cowiche Water Association compare with other water systems in Yakima County?
By EPA's size categories, Cowiche Water Association is a very small system (500 people or fewer). Yakima County has 217 active public water systems. Its population served is well below the county average of 1,230 people per system, and accounts for less than 0.1% of the 266,832 people reported by systems filed under the county. Across Washington, the 4,705 active systems average 2,172 people each. Nationally, the average active community water system reports serving 6,703 people, so Cowiche Water Association 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. Washington has 2,392 active community water systems, 51% 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 Cowiche Water Association?
EPA lists Cowiche Water Association 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. 182 of the 217 active systems in Yakima County (84%) are also privately owned.
Does Cowiche Water Association have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2023. The violations listed here began between January 2005 and July 2023. By type: 8 monitoring and reporting, 3 monitoring and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Revised Total Coliform Rule (3 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 |
|---|---|---|---|---|
| 2023-07-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2019-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2019-06-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2018-09-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloropropanecode 2983 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1,2-Trichloroethanecode 2985 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Tetrachloroethylenecode 2987 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | cis-1,2-Dichloroethylenecode 2380 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1,1-Trichloroethanecode 2981 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | o-Dichlorobenzenecode 2968 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | p-Dichlorobenzenecode 2969 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2,4-Trichlorobenzenecode 2378 | 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.
Cowiche Water Association: frequently asked questions
Who runs Cowiche Water Association?
Cowiche Water Association (PWSID WA5304316) is a community water system privately owned. It is regulated by the WA state drinking water program.
How many people does Cowiche Water Association serve?
Cowiche Water Association reports serving 48 people through 18 service connections in Yakima County, Washington.
Where does Cowiche Water Association 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 Cowiche Water Association 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 July 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 Cowiche Water Association'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, none is health-based, and the most recent began in July 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the WA state drinking water program.
Where can I find Cowiche Water Association's water quality report?
As a community water system, Cowiche Water Association 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 Yakima County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Yakima Water Division City of | Yakima | 112,858 | Community | Surface water |
| Nob Hill Water Association | Yakima | 38,050 | Community | Groundwater |
| Sunnyside City of | Yakima | 17,194 | Community | Groundwater |
| Grandview City of | Yakima | 11,010 | Community | Groundwater |
| Selah City of | Yakima | 9,331 | Community | Groundwater |
| Toppenish Water Department | Yakima | 8,950 | Community | Groundwater |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Cowiche Water Association, PWSID WA5304316, Washington”, https://aquacensus.com/water-systems/washington/cowiche-water-association-wa5304316 (data as of October 1, 2026).