Public water system · WA5304643
ActiveSierra Water System
At a glance
Sierra Water System (PWSID WA5304643) is an active community water system in Pierce County, Washington. It reports serving 355 people through 152 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, none is health-based, and the most recent began in October 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
355
Service connections
152
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Sierra Water System compare with other water systems in Pierce County?
By EPA's size categories, Sierra Water System is a very small system (500 people or fewer). Pierce County has 358 active public water systems. Its population served is well below the county average of 3,335 people per system, and accounts for less than 0.1% of the 1,193,797 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 Sierra 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 Sierra Water System?
EPA lists Sierra Water System 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. 74 of the 358 active systems in Pierce County (21%) are also owned by a local government.
Does Sierra Water System have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 2025. The violations listed here began between October 2025 and October 2025. By type: 12 monitoring and reporting. The contaminants or rules involved are 1,2-Dichloroethane, Endrin, Chlordane and 1,2-Dichloropropane. EPA lists 12 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 |
|---|---|---|---|---|
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloroethanecode 2980 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Endrincode 2005 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlordanecode 2959 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloropropanecode 2983 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Benzenecode 2990 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Carbon tetrachloridecode 2982 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Toxaphenecode 2020 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Toluenecode 2991 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | p-Dichlorobenzenecode 2969 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Styrenecode 2996 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dalaponcode 2031 | No | Archived |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2,4-Trichlorobenzenecode 2378 | 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.
Sierra Water System: frequently asked questions
Who runs Sierra Water System?
Sierra Water System (PWSID WA5304643) is a community water system owned by a local government. It is regulated by the WA state drinking water program.
How many people does Sierra Water System serve?
Sierra Water System reports serving 355 people through 152 service connections in Pierce County, Washington.
Where does Sierra 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 Sierra Water System 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 October 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 Sierra 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. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 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 Sierra Water System's water quality report?
As a community water system, Sierra 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 Pierce County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Tacoma Water Division City of | Pierce | 446,170 | Community | Surface water |
| Puyallup City of | Pierce | 94,520 | Community | Purchased surface water |
| Lakewood Water District | Pierce | 82,425 | Community | Groundwater |
| Southwood | Pierce | 64,155 | Community | Purchased surface water |
| Bonney Lake Water Department City | Pierce | 43,371 | Community | Purchased surface water |
| Firgrove Mutual Inc. | Pierce | 36,168 | Community | Purchased surface water |
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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, “Sierra Water System, PWSID WA5304643, Washington”, https://aquacensus.com/water-systems/washington/sierra-water-system-wa5304643 (data as of October 1, 2026).