PlainWater

Non-Transient Non-Community Water System · PWS 105338116

Stillaguamish Natural Resources

Arlington, EPA Region 10 — Tribal Water Systems 98223 - drinking water served from groundwater sources to 31 people, tracked in EPA SDWIS and UCMR5.

31
People served
18
EPA violations
0
Health-based
Untested
UCMR5 result

The verdict

EPA records 18 drinking-water violations at Stillaguamish Natural Resources.

18
Total EPA violations on record
0%
Health-based (MCL / treatment failure)
31
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Stillaguamish Natural Resources

Stillaguamish Natural Resources is a native american-owned non-transient non-community water system that delivers drinking water to 31 residents in Arlington, EPA Region 10 — Tribal Water Systems through 1 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 18 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 14 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.

The most frequently cited contaminant at this system is Chlorine, recorded in 5 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

EPA Region 10 — Tribal Water Systems has thousands of regulated public water systems tracked by EPA under the Safe Drinking Water Act.

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
31
Total Violations
18
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Non-Transient Non-Community
Owner Type
Native American
Connections
1
School/Daycare
No
MCL Violations
0
Monitoring Violations
14
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Chlorine MR 5 2025
Revised Total Coliform Rule RPT 4 2025
Total Haloacetic Acids (HAA5) MR 3 2023
TTHM MR 3 2023
Lead and Copper Rule MR 2 2021
Revised Total Coliform Rule MON 1 2025

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 Stillaguamish Natural Resources.

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 105338116 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

EPA Region 10 — Tribal Water Systems Drinking Water Authority

EPA Region 10 — Tribal Water Systems's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find 10 regulator via EPA SDWIS

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
2025 Chlorine MR 5 SDWIS / 105338116 / 0999
2025 Revised Total Coliform Rule RPT 4 SDWIS / 105338116 / 8000
2025 Revised Total Coliform Rule MON 1 SDWIS / 105338116 / 8000
2023 Total Haloacetic Acids (HAA5) MR 3 SDWIS / 105338116 / 2456
2023 TTHM MR 3 SDWIS / 105338116 / 2950
2021 Lead and Copper Rule MR 2 SDWIS / 105338116 / 5000

How Stillaguamish Natural Resources Compares

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

Metric Stillaguamish Natural Resources EPA Region 10 — Tribal Water Systems avg Federal benchmark
Total violations 18 - SDWA compliance, any non-zero count is a recorded breach
Health-based violations 0 - Indicates a contaminant exceeded a federal MCL
PFAS detection None - EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 31 - Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across all regulated public water systems in EPA Region 10 — Tribal Water Systems.

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 Stillaguamish Natural Resources water safe to drink?
Stillaguamish Natural Resources (PWS ID: 105338116) has 18 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 31 people using Groundwater sources.
How many people does Stillaguamish Natural Resources serve?
Stillaguamish Natural Resources serves 31 people in Arlington, EPA Region 10 — Tribal Water Systems. It is a Native American-owned system using Groundwater water sources with 1 service connections.
What type of violations does Stillaguamish Natural Resources have?
Stillaguamish Natural Resources has 18 total violations: 0 health-based violations (MCL exceedances or treatment failures), 14 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Stillaguamish Natural Resources water?
No PFAS testing data is available for Stillaguamish Natural Resources under the EPA's UCMR5 monitoring program.
What water source does Stillaguamish Natural Resources use?
Stillaguamish Natural Resources uses Groundwater as its primary water source. It is classified as a Non-Transient Non-Community Water System, serving the same people for at least 6 months per year.
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.
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.