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States → Montana

Community Water System · PWS MT0000200

Devon Water Inc

Shelby, Montana 59474 - drinking water served from groundwater sources to 75 people, tracked in EPA SDWIS and UCMR5.

75
People served
787
EPA violations
58
Health-based
Untested
UCMR5 result

The verdict

EPA records 787 drinking-water violations at Devon Water Inc, 7% of them health-based - above the Montana per-system average.

787
Total EPA violations on record
7%
Health-based (MCL / treatment failure)
75
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Devon Water Inc

Devon Water Inc is a private-owned community water system that delivers drinking water to 75 residents in Shelby, Montana (Toole County) through 24 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 787 total violations for this system , of which 58 (7%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 707 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 Arsenic, recorded in 31 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 Montana, EPA tracks 2,263 public water systems serving 1,112,267 people, with 297,270 cumulative violations and 25,922 health-based violations on record. About 95% of systems in the state carry at least one violation, and state-wide the average per system is 131.4 violations. Statewide, 5 of 45 UCMR5-tested systems have reported PFAS detections (11.1%).

Devon Water Inc's 787 violations sit above the Montana 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
75
Total Violations
787
Health-Based Violations
58
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
24
County
Toole
School/Daycare
No
MCL Violations
56
Monitoring Violations
707
Treatment Tech Violations
2

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Arsenic MR 31 2017
Total Haloacetic Acids (HAA5) MCL 30 2019
Total Haloacetic Acids (HAA5) MR 26 2020
TTHM MR 26 2020
TTHM MCL 26 2019
Lead and Copper Rule MR 24 2025
Xylenes, Total MR 20 2019
p-Dichlorobenzene MR 20 2019
Vinyl chloride MR 20 2019
o-Dichlorobenzene MR 20 2019
CHLOROBENZENE MR 20 2019
1,1,2-Trichloroethane MR 20 2019
1,2-Dichloropropane MR 20 2019
cis-1,2-Dichloroethylene MR 20 2019
trans-1,2-Dichloroethylene MR 20 2019
1,1-Dichloroethylene MR 20 2019
Trichloroethylene MR 20 2019
Benzene MR 20 2019
1,2-Dichloroethane MR 20 2019
1,1,1-Trichloroethane MR 20 2019
Carbon tetrachloride MR 20 2019
Tetrachloroethylene MR 20 2019
Toluene MR 20 2019
Styrene MR 20 2019
1,2,4-Trichlorobenzene MR 20 2019
Consumer Confidence Rule Other 20 2024
Ethylbenzene MR 20 2019
DICHLOROMETHANE MR 19 2019
Surface Water Treatment Rule MR 18 2008
Thallium, Total MR 16 2014

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 Devon Water Inc.

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 MT0000200 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Montana Drinking Water Authority

Montana'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 MT 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 Lead and Copper Rule MR 24 SDWIS / MT0000200 / 5000
2024 Consumer Confidence Rule Other 20 SDWIS / MT0000200 / 7000
2020 Total Haloacetic Acids (HAA5) MR 26 SDWIS / MT0000200 / 2456
2020 TTHM MR 26 SDWIS / MT0000200 / 2950
2019 Total Haloacetic Acids (HAA5) MCL 30 SDWIS / MT0000200 / 2456
2019 TTHM MCL 26 SDWIS / MT0000200 / 2950
2019 Xylenes, Total MR 20 SDWIS / MT0000200 / 2955
2019 p-Dichlorobenzene MR 20 SDWIS / MT0000200 / 2969
2019 Vinyl chloride MR 20 SDWIS / MT0000200 / 2976
2019 o-Dichlorobenzene MR 20 SDWIS / MT0000200 / 2968
2019 CHLOROBENZENE MR 20 SDWIS / MT0000200 / 2989
2019 1,1,2-Trichloroethane MR 20 SDWIS / MT0000200 / 2985
2019 1,2-Dichloropropane MR 20 SDWIS / MT0000200 / 2983
2019 cis-1,2-Dichloroethylene MR 20 SDWIS / MT0000200 / 2380
2019 trans-1,2-Dichloroethylene MR 20 SDWIS / MT0000200 / 2979

How Devon Water Inc Compares

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

Metric Devon Water Inc Montana avg Federal benchmark
Total violations 787 131.4 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 58 11.5 Indicates a contaminant exceeded a federal MCL
PFAS detection None 11.1% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 75 492 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,263 regulated public water systems in Montana.

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 Devon Water Inc water safe to drink? ▼
Devon Water Inc (PWS ID: MT0000200) has 787 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 75 people using Groundwater sources.
How many people does Devon Water Inc serve? ▼
Devon Water Inc serves 75 people in Shelby, Montana. It is a Private-owned system using Groundwater water sources with 24 service connections.
What type of violations does Devon Water Inc have? ▼
Devon Water Inc has 787 total violations: 58 health-based violations (MCL exceedances or treatment failures), 707 monitoring/reporting violations, and 2 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Devon Water Inc water? ▼
No PFAS testing data is available for Devon Water Inc under the EPA's UCMR5 monitoring program.
What water source does Devon Water Inc use? ▼
Devon Water Inc 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.