Public water system · WA5343600
ActiveLake Arrowhead
At a glance
Lake Arrowhead (PWSID WA5343600) is an active community water system in Mason County, Washington. It reports serving 343 people through 258 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 5 violations for this system; 4 are health-based, and the most recent began in February 2004.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
343
Service connections
258
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Lake Arrowhead compare with other water systems in Mason County?
By EPA's size categories, Lake Arrowhead is a very small system (500 people or fewer). Mason County has 240 active public water systems. Its population served is roughly in line with the county average of 315 people per system, and accounts for 0.5% of the 75,633 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 Lake Arrowhead 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 Lake Arrowhead?
EPA lists Lake Arrowhead 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. 64 of the 240 active systems in Mason County (27%) are also owned by a local government.
Does Lake Arrowhead have drinking water violations?
EPA's records list 5 violations for this system; 4 are health-based, and the most recent began in February 2004. The violations listed here began between September 1995 and February 2004. By type: 4 contaminant level above the legal limit and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Total coliform bacteria (TCR) (4 of them). EPA lists 4 as archived and 1 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 |
|---|---|---|---|---|
| 2004-02-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 2000-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 1998-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1998-03-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1995-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
All 5 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.
Lake Arrowhead: frequently asked questions
Who runs Lake Arrowhead?
Lake Arrowhead (PWSID WA5343600) is a community water system owned by a local government. It is regulated by the WA state drinking water program.
How many people does Lake Arrowhead serve?
Lake Arrowhead reports serving 343 people through 258 service connections in Mason County, Washington.
Where does Lake Arrowhead 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 Lake Arrowhead have any drinking water violations?
EPA's records list 5 violations for this system; 4 are health-based, and the most recent began in February 2004. 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 Lake Arrowhead'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 5 violations for this system; 4 are health-based, and the most recent began in February 2004. For current results, consult the system's annual water quality report, EPA ECHO, or the WA state drinking water program.
Where can I find Lake Arrowhead's water quality report?
As a community water system, Lake Arrowhead 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 Mason County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Shelton City of | Mason | 15,089 | Community | Groundwater |
| Belfair Water District 1 | Mason | 4,432 | Community | Groundwater |
| Lake Cushman System 5 | Mason | 3,675 | Community | Groundwater |
| Twanoh State Park | Mason | 3,173 | Transient non-community | Groundwater |
| Belfair State Park | Mason | 2,411 | Transient non-community | Groundwater |
| Timberlake Community Club Inc. | Mason | 2,337 | 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, “Lake Arrowhead, PWSID WA5343600, Washington”, https://aquacensus.com/water-systems/washington/lake-arrowhead-wa5343600 (data as of October 1, 2026).