Public water system · WA5375340
ActiveMaples Plat Water System
At a glance
Maples Plat Water System (PWSID WA5375340) is an active community water system in Grant County, Washington. It reports serving 30 people through 12 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 9 violations for this system; none is health-based, and the most recent began in October 1979.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
30
Service connections
12
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Maples Plat Water System compare with other water systems in Grant County?
By EPA's size categories, Maples Plat Water System is a very small system (500 people or fewer). Grant County has 265 active public water systems. Its population served is well below the county average of 543 people per system, and accounts for less than 0.1% of the 143,944 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 Maples Plat Water System 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 Maples Plat Water System?
EPA lists Maples Plat Water System 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. 227 of the 265 active systems in Grant County (86%) are also privately owned.
Does Maples Plat Water System have drinking water violations?
EPA's records list 9 violations for this system; none is health-based, and the most recent began in October 1979. The violations listed here began between October 1979 and October 1979. By type: 9 monitoring and reporting. The contaminants or rules involved are Nitrate, Selenium, Cadmium and Mercury. EPA lists 9 as archived. 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Archived |
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Seleniumcode 1045 | No | Archived |
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Cadmiumcode 1015 | No | Archived |
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Mercurycode 1035 | No | Archived |
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chromiumcode 1020 | 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 | Gross alpha (excluding radon and uranium)code 4000 | No | Archived |
| 1979-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Fluoridecode 1025 | No | Archived |
All 9 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.
Maples Plat Water System: frequently asked questions
Who runs Maples Plat Water System?
Maples Plat Water System (PWSID WA5375340) is a community water system privately owned. It is regulated by the WA state drinking water program.
How many people does Maples Plat Water System serve?
Maples Plat Water System reports serving 30 people through 12 service connections in Grant County, Washington.
Where does Maples Plat Water System 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 Maples Plat Water System have any drinking water violations?
EPA's records list 9 violations for this system; none is health-based, and the most recent began in October 1979. 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 Maples Plat Water System'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 9 violations for this system; none is health-based, and the most recent began in October 1979. For current results, consult the system's annual water quality report, EPA ECHO, or the WA state drinking water program.
Where can I find Maples Plat Water System's water quality report?
As a community water system, Maples Plat Water System 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 Grant County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Moses Lake City of | Grant | 32,428 | Community | Groundwater |
| Gorge Amphitheatre | Grant | 25,119 | Transient non-community | Groundwater |
| Ephrata Water Department | Grant | 8,718 | Community | Groundwater |
| Quincy Water Department City of | Grant | 8,415 | Community | Groundwater |
| Mattawa City of | Grant | 5,370 | Community | Groundwater |
| Sun Lakes State Park | Grant | 4,858 | 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, “Maples Plat Water System, PWSID WA5375340, Washington”, https://aquacensus.com/water-systems/washington/maples-plat-water-system-wa5375340 (data as of October 1, 2026).