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Community Water System · PWS WA5387115

Tahuya River Valley Water District

Shelton, Washington 98584-5034 - drinking water served from groundwater sources to 367 people, tracked in EPA SDWIS and UCMR5.

367
People served
281
EPA violations
7
Health-based
Untested
UCMR5 result

The verdict

EPA records 281 drinking-water violations at Tahuya River Valley Water District, 2% of them health-based - above the Washington per-system average.

281
Total EPA violations on record
2%
Health-based (MCL / treatment failure)
367
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Tahuya River Valley Water District

Tahuya River Valley Water District is a local-owned community water system that delivers drinking water to 367 residents in Shelton, Washington (Mason County) through 164 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 281 total violations for this system , of which 7 (2%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 269 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.

The most frequently cited contaminant at this system is Heptachlor epoxide, recorded in 18 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across Washington, EPA tracks 4,557 public water systems serving 9,736,844 people, with 314,648 cumulative violations and 20,590 health-based violations on record. About 92% of systems in the state carry at least one violation, and state-wide the average per system is 69 violations. Statewide, 98 of 247 UCMR5-tested systems have reported PFAS detections (39.7%).

Tahuya River Valley Water District's 281 violations sit above the Washington average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
367
Total Violations
281
Health-Based Violations
7
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
164
County
Mason
School/Daycare
No
MCL Violations
7
Monitoring Violations
269
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Heptachlor epoxide MR 18 2005
Lead and Copper Rule MR 11 2009
Coliform (TCR) MCL 7 1997
p-Dichlorobenzene MR 6 2005
Vinyl chloride MR 6 2005
1,1-Dichloroethylene MR 6 2005
trans-1,2-Dichloroethylene MR 6 2005
1,2-Dichloroethane MR 6 2005
1,1,1-Trichloroethane MR 6 2005
Carbon tetrachloride MR 6 2005
Trichloroethylene MR 6 2005
1,1,2-Trichloroethane MR 6 2005
Tetrachloroethylene MR 6 2005
CHLOROBENZENE MR 6 2005
Benzene MR 6 2005
Toluene MR 6 2005
Styrene MR 6 2005
DICHLOROMETHANE MR 6 2005
Pentachlorophenol MR 6 2005
o-Dichlorobenzene MR 6 2005
Ethylbenzene MR 6 2005
cis-1,2-Dichloroethylene MR 6 2005
1,2-Dichloropropane MR 6 2005
1,2,4-Trichlorobenzene MR 6 2005
Barium MR 5 2005
Cadmium MR 5 2005
Chromium MR 5 2005
Fluoride MR 5 2005
Selenium MR 5 2005
Mercury MR 5 2005

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Tahuya River Valley Water District.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID WA5387115 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Washington Drinking Water Authority

Washington State Department of Health, Office of Drinking Water is the primacy agency that licenses and inspects Tahuya River Valley Water District under EPA-delegated authority.

Open WA regulator portal

Source: Washington State Department of Health, Office of Drinking Water

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2024 Consumer Confidence Rule Other 1 SDWIS / WA5387115 / 7000
2021 Nitrate MR 3 SDWIS / WA5387115 / 1040
2009 Lead and Copper Rule MR 11 SDWIS / WA5387115 / 5000
2005 Heptachlor epoxide MR 18 SDWIS / WA5387115 / 2067
2005 p-Dichlorobenzene MR 6 SDWIS / WA5387115 / 2969
2005 Vinyl chloride MR 6 SDWIS / WA5387115 / 2976
2005 1,1-Dichloroethylene MR 6 SDWIS / WA5387115 / 2977
2005 trans-1,2-Dichloroethylene MR 6 SDWIS / WA5387115 / 2979
2005 1,2-Dichloroethane MR 6 SDWIS / WA5387115 / 2980
2005 1,1,1-Trichloroethane MR 6 SDWIS / WA5387115 / 2981
2005 Carbon tetrachloride MR 6 SDWIS / WA5387115 / 2982
2005 Trichloroethylene MR 6 SDWIS / WA5387115 / 2984
2005 1,1,2-Trichloroethane MR 6 SDWIS / WA5387115 / 2985
2005 Tetrachloroethylene MR 6 SDWIS / WA5387115 / 2987
2005 CHLOROBENZENE MR 6 SDWIS / WA5387115 / 2989

How Tahuya River Valley Water District Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Tahuya River Valley Water District Washington avg Federal benchmark
Total violations 281 69 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 7 4.5 Indicates a contaminant exceeded a federal MCL
PFAS detection None 39.7% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 367 2,137 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 4,557 regulated public water systems in Washington.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Tahuya River Valley Water District water safe to drink? ▼
Tahuya River Valley Water District (PWS ID: WA5387115) has 281 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 367 people using Groundwater sources.
How many people does Tahuya River Valley Water District serve? ▼
Tahuya River Valley Water District serves 367 people in Shelton, Washington. It is a Local-owned system using Groundwater water sources with 164 service connections.
What type of violations does Tahuya River Valley Water District have? ▼
Tahuya River Valley Water District has 281 total violations: 7 health-based violations (MCL exceedances or treatment failures), 269 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Tahuya River Valley Water District water? ▼
No PFAS testing data is available for Tahuya River Valley Water District under the EPA's UCMR5 monitoring program.
What water source does Tahuya River Valley Water District use? ▼
Tahuya River Valley Water District uses Groundwater as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.