Public water system · WA5351350

Active

Maple Vista

At a glance

Maple Vista (PWSID WA5351350) is an active community water system in King County, Washington. It reports serving 57 people through 21 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 10 violations for this system; 2 are health-based, and the most recent began in January 2020.

Dataset updated October 2026 . Source: EPA SDWIS/ECHO public records.

Population served

Service connections

Primary source

Groundwater

System type

CWS

Community water system

System record

PWSIDWA5351350

System typeCommunity water system

Activity statusActive

Population served57

Service connections21

Primary water sourceGroundwater

Owner typePrivate

Primacy agencyWA state drinking water program

City served—

StateWashington

ZIP—

CountyKing County

How does Maple Vista compare with other water systems in King County?

By EPA's size categories, Maple Vista is a very small system (500 people or fewer). King County has 214 active public water systems. Its population served is well below the county average of 15,523 people per system, and accounts for less than 0.1% of the 3,321,960 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 Maple Vista 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 Maple Vista?

EPA lists Maple Vista 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. 142 of the 214 active systems in King County (66%) are also privately owned.

Does Maple Vista have drinking water violations?

EPA's records list 10 violations for this system; 2 are health-based, and the most recent began in January 2020. The violations listed here began between October 1979 and January 2020. By type: 8 monitoring and reporting and 2 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (7 of them). EPA lists 8 as archived and 2 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
2020-01-01	Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52	Lead and Copper Rulecode 5000	No	Resolved
2007-01-01	Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52	Lead and Copper Rulecode 5000	No	Resolved
2004-09-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Archived
2000-09-01	Monitoring and reportingMonitoring, Routine Major (TCR) · code 23	Total coliform bacteria (TCR)code 3100	No	Archived
1999-06-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Archived
1993-11-01	Monitoring and reportingMonitoring, Routine Major (TCR) · code 23	Total coliform bacteria (TCR)code 3100	No	Archived
1992-05-01	Monitoring and reportingMonitoring, Routine Major (TCR) · code 23	Total coliform bacteria (TCR)code 3100	No	Archived
1991-11-01	Monitoring and reportingMonitoring, Routine Major (TCR) · code 23	Total coliform bacteria (TCR)code 3100	No	Archived
1991-10-01	Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26	Total coliform bacteria (TCR)code 3100	No	Archived
1979-10-01	Monitoring and reportingMonitoring, Regular · code 03	Gross alpha (excluding radon and uranium)code 4000	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.

Maple Vista: frequently asked questions

Who runs Maple Vista?

Maple Vista (PWSID WA5351350) is a community water system privately owned. It is regulated by the WA state drinking water program.

How many people does Maple Vista serve?

Maple Vista reports serving 57 people through 21 service connections in King County, Washington.

Where does Maple Vista 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 Maple Vista have any drinking water violations?

EPA's records list 10 violations for this system; 2 are health-based, and the most recent began in January 2020. 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 Maple Vista'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; 2 are health-based, and the most recent began in January 2020. For current results, consult the system's annual water quality report, EPA ECHO, or the WA state drinking water program.

Where can I find Maple Vista's water quality report?

As a community water system, Maple Vista 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 King County

Water system	County	Population served	Type	Source
Seattle Public Utilities	King	1,161,961	Community	Surface water
Bellevue City of	King	321,349	Community	Purchased surface water
Kent Water Department	King	166,421	Community	Purchased surface water
Redmond Water System City of	King	163,335	Community	Purchased surface water
Lakehaven Water and Sewer District	King	148,809	Community	Purchased surface water
Renton City of	King	108,091	Community	Groundwater

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, “Maple Vista, PWSID WA5351350, Washington”, https://aquacensus.com/water-systems/washington/maple-vista-wa5351350 (data as of October 1, 2026).