Public water system · WA5332735
ActiveHighland Estates
At a glance
Highland Estates (PWSID WA5332735) is an active community water system in Mason County, Washington. It reports serving 110 people through 44 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in November 1998.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
110
Service connections
44
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Highland Estates compare with other water systems in Mason County?
By EPA's size categories, Highland Estates is a very small system (500 people or fewer). Mason County has 240 active public water systems. Its population served is about 65% below the county average of 315 people per system, and accounts for 0.1% 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 Highland Estates 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 Highland Estates?
EPA lists Highland Estates 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 Highland Estates have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in November 1998. The violations listed here began between October 1979 and November 1998. By type: 11 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (5 of them). EPA lists 11 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 |
|---|---|---|---|---|
| 1998-11-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1997-07-01 | Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1995-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1995-06-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1995-02-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1991-12-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Seleniumcode 1045 | No | Archived |
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Archived |
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Archived |
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Bariumcode 1010 | No | Archived |
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Archived |
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Mercurycode 1035 | No | Archived |
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.
Highland Estates: frequently asked questions
Who runs Highland Estates?
Highland Estates (PWSID WA5332735) is a community water system owned by a local government. It is regulated by the WA state drinking water program.
How many people does Highland Estates serve?
Highland Estates reports serving 110 people through 44 service connections in Mason County, Washington.
Where does Highland Estates 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 Highland Estates have any drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in November 1998. 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 Highland Estates' 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, one is health-based, and the most recent began in November 1998. For current results, consult the system's annual water quality report, EPA ECHO, or the WA state drinking water program.
Where can I find Highland Estates' water quality report?
As a community water system, Highland Estates 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 |
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, “Highland Estates, PWSID WA5332735, Washington”, https://aquacensus.com/water-systems/washington/highland-estates-wa5332735 (data as of October 1, 2026).