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WHITEHORSE MERCANTILE WATER SYSTEM

PWS ID: WA5364401 · Arlington, Washington 98223

WHITEHORSE MERCANTILE WATER SYSTEM serves 930 people in Arlington, Washington using Groundwater water sources. It has 22 recorded EPA violations, including 0 health-based violations. No PFAS contamination was detected in UCMR5 testing.

Water Quality Snapshot: WHITEHORSE MERCANTILE WATER SYSTEM

WHITEHORSE MERCANTILE WATER SYSTEM is a private-owned transient non-community water system that delivers drinking water to 930 residents in Arlington, Washington (Snohomish County) through 1 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 22 total violations for this system , of which 0 (0%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 19 monitoring and reporting violations are on file. The most recent violation on record dates to 2018.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 10 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. WHITEHORSE MERCANTILE WATER SYSTEM's 22 violations sit below the Washington average. Statewide, 98 of 247 UCMR5-tested systems have reported PFAS detections (39.7%). 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
930
Total Violations
22
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Transient Non-Community
Owner Type
Private
Connections
1
County
Snohomish
School/Daycare
No
MCL Violations
0
Monitoring Violations
19
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 10 2012
Nitrate MR 9 2018

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 WHITEHORSE MERCANTILE WATER SYSTEM.

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 WA5364401 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 WHITEHORSE MERCANTILE WATER SYSTEM 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
2018 Nitrate MR 9 SDWIS / WA5364401 / 1040
2012 Coliform (TCR) MR 10 SDWIS / WA5364401 / 3100

How WHITEHORSE MERCANTILE WATER SYSTEM Compares

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

Metric WHITEHORSE MERCANTILE WATER SYSTEM Washington avg Federal benchmark
Total violations 22 69 SDWA compliance — any non-zero count is a recorded breach
Health-based violations 0 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 930 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
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is WHITEHORSE MERCANTILE WATER SYSTEM water safe to drink?
WHITEHORSE MERCANTILE WATER SYSTEM (PWS ID: WA5364401) has 22 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 930 people using Groundwater sources.
How many people does WHITEHORSE MERCANTILE WATER SYSTEM serve?
WHITEHORSE MERCANTILE WATER SYSTEM serves 930 people in Arlington, Washington. It is a Private-owned system using Groundwater water sources with 1 service connections.
What type of violations does WHITEHORSE MERCANTILE WATER SYSTEM have?
WHITEHORSE MERCANTILE WATER SYSTEM has 22 total violations: 0 health-based violations (MCL exceedances or treatment failures), 19 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in WHITEHORSE MERCANTILE WATER SYSTEM water?
No PFAS testing data is available for WHITEHORSE MERCANTILE WATER SYSTEM under the EPA's UCMR5 monitoring program.
What water source does WHITEHORSE MERCANTILE WATER SYSTEM use?
WHITEHORSE MERCANTILE WATER SYSTEM uses Groundwater as its primary water source. It is classified as a Transient Non-Community Water System, serving transient populations.
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.

Explore PlainWater

Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Related

Data sourced from $official public datasets. See our methodology for details. Retrieved and formatted by Kiznis Studio Editorial