Public water system · WA5311850
ActiveCathlamet Water Dept
At a glance
Cathlamet Water Dept (PWSID WA5311850) is an active community water system in Wahkiakum County, Washington. It reports serving 1,636 people through 739 service connections. Its primary water source is surface water, 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 September 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,636
Service connections
739
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does Cathlamet Water Dept compare with other water systems in Wahkiakum County?
By EPA's size categories, Cathlamet Water Dept is a small system (501 to 3,300 people). Wahkiakum County has 6 active public water systems, and Cathlamet Water Dept is the largest of them by population served. Its population served is about 163% above the county average of 621 people per system, and accounts for 44% of the 3,726 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 Cathlamet Water Dept 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. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 140 Washington systems (3%) list surface water as their primary source.
Who owns and regulates Cathlamet Water Dept?
EPA lists Cathlamet Water Dept as owned by a local government. 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. 6 of the 6 active systems in Wahkiakum County (100%) are also owned by a local government.
Does Cathlamet Water Dept have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in September 2025. The violations listed here began between January 2008 and September 2025. By type: 10 monitoring and reporting and 2 public notice, recordkeeping or other. The contaminant or rule involved most often is Surface Water Treatment Rule (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 |
|---|---|---|---|---|
| 2025-09-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2024-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2022-07-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Bariumcode 1010 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | cis-1,2-Dichloroethylenecode 2380 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chromiumcode 1020 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Berylliumcode 1075 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nickelcode 1036 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Cadmiumcode 1015 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Fluoridecode 1025 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Seleniumcode 1045 | 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.
Cathlamet Water Dept: frequently asked questions
Who runs Cathlamet Water Dept?
Cathlamet Water Dept (PWSID WA5311850) is a community water system owned by a local government. It is regulated by the WA state drinking water program.
How many people does Cathlamet Water Dept serve?
Cathlamet Water Dept reports serving 1,636 people through 739 service connections in Wahkiakum County, Washington.
Where does Cathlamet Water Dept get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does Cathlamet Water Dept 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 September 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 Cathlamet Water Dept'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 September 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the WA state drinking water program.
Where can I find Cathlamet Water Dept's water quality report?
As a community water system, Cathlamet Water Dept 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 Wahkiakum County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Puget Island | Wahkiakum | 920 | Community | Purchased surface water |
| Western Wahkiakum | Wahkiakum | 791 | Community | Groundwater |
| Skamokawa Water System | Wahkiakum | 267 | Community | Groundwater |
| Skamokawa Vista Park | Wahkiakum | 87 | Transient non-community | Groundwater |
| County Line Park | Wahkiakum | 25 | Transient non-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, “Cathlamet Water Dept, PWSID WA5311850, Washington”, https://aquacensus.com/water-systems/washington/cathlamet-water-dept-wa5311850 (data as of October 1, 2026).