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Devon Water Inc

What EPA’s and Montana’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.

Serves
75 people
Connections
24
Water source
Groundwater bought from another system
Based in
Shelby, MT
County
Toole
Owner
Private
The ZIP code it serves

59474

The short answer

1 result is above the health goal. The worst: Arsenic, above the health goal. 2 health-based violations since 2016.

What handles it

What was found

Haloacetic acids (HAA5), total trihalomethanes (TTHM) and nitrate: Montana’s own results, samples taken from Jan. 8, 2020 to Jan. 11, 2021, with EPA’s 2012 to 2019 file for earlier years.

Arsenic, fluoride and chromium (total): EPA’s compliance monitoring file, samples taken from Jan. 29, 2013 to March 5, 2018. Newer results are in the utility’s annual water quality report.

Above the health goal1

Arsenic

Comes from the source

Above the health goal

2.0ppb

Highest yearly average, 2013 to 2018

2018: not found

Averaged by year, the highest was 2.0 ppb, in 2013: below EPA’s legal limit of 10 ppb, but above its health goal of zero. In 2018, the latest year on file, it wasn’t found in its one sample.

What handles it

  • NSF/ANSI 58 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
  • NSF/ANSI 53 look for “Arsenic (Pentavalent)<=50 ppb Reduction”

Below EPA’s limits4

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

42.4ppb

Highest yearly average, 2020

Averaged by year, the highest was 42.4 ppb, in 2020, below EPA’s legal limit of 60 ppb. Its highest single sample was 72.9 ppb. That is the only year on file. EPA recorded no violation for haloacetic acids (HAA5) at this utility since 2020. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 58.2 ppb, in 2018, and EPA recorded violations in 2012 and 2019.

What handles it

No certification claim covers this compound yet.

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

52.7ppb

Highest yearly average, 2020

Averaged by year, the highest was 52.7 ppb, in 2020, below EPA’s legal limit of 80 ppb. Its highest single sample was 86.9 ppb. That is the only year on file. EPA recorded no violation for total trihalomethanes (TTHM) at this utility since 2020. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 93.3 ppb, in 2018, and EPA recorded violations in 2012 and 2019.

What handles it

  • NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
  • NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.21ppm

Highest yearly average, 2013 to 2016

Averaged by year, the highest was 0.21 ppm, in 2016, below EPA’s legal limit of 4.0 ppm. That was also the latest year on file.

What handles it

Nitrate

Comes from the source

Below EPA’s limits

0.28ppm

Highest sample; found in 1 of 2

2021: not found

The highest sample, in 2020, was 0.28 ppm, below EPA’s legal limit of 10 ppm. In 2021, the latest year on file, it wasn’t found in its one sample. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.77 ppm, in 2012.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
2 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Chromium (total)
  • Lead

What handles it

A certification covers specific claims, not a whole standard. Look for these claims on the certifier’s listing, not the box. Wording varies a little: NSF writes “Lead Reduction,” WQA just “Lead.”

  • NSF/ANSI 53

    Claim: Arsenic (Pentavalent)<=50 ppb Reduction

    For: Arsenic

    Other certifiers’ wording: Arsenic (III) (50 ppb influent level)

  • NSF/ANSI 58

    Claim: Arsenic (Pentavalent)<=50 ppb Reduction

    For: Arsenic

    Other certifiers’ wording: Arsenic (Pentavalent)<=300 ppb Reduction; Arsenic (V) (300 ppb influent level)

At the tap, or for the whole house?

These come with the water itself, so a whole-house system certified for the same claims treats every tap and shower. A filter at the tap treats drinking water for much less. How whole-house systems compare.

Filters with those claims on a certifier’s listing

Disclosure: TapBuff earns a commission if you buy through some links on this page. It does not change which standard or filter we name. As an Amazon Associate, TapBuff earns from qualifying purchases. How TapBuff makes money

Compare five-year costs

The best reverse osmosis systems, ranked

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2019 to June 30, 201984.9 UG/LResolved
Total Haloacetic Acids (HAA5)The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2019 to June 30, 201962.5 UG/LResolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 58 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Haloacetic acids (HAA5), total trihalomethanes (TTHM) and nitrate results here are Montana’s own from 2020 on, with EPA’s national file for 2012 to 2019. Arsenic, fluoride and chromium (total) come from EPA’s file alone, which ends in 2019. Devon Water Inc’s own annual report, which it must send you every year, has newer results for those and the contaminants this page does not show.

  • Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.

  • What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.

  • Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; Montana’s results run from Jan. 8, 2020 to Jan. 11, 2021; EPA’s compliance samples are from Jan. 29, 2013 to March 5, 2018.

Testing your own tap

Devon Water Inc’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab Montana certifies.

No lab Montana certifies is within 75 miles of the area Devon Water Inc serves on the state’s list. Some take samples by mail; the state’s page lists them all.

Montana State Environmental Laboratory: Private well testing packages for bacteria, metals, nutrients, anions, organic chemicals and more, open to the public. Samples can be mailed, sent by the lab's free courier, or dropped off at the lab. Environmental Laboratory, Montana Department of Public Health and Human Services.

All 36 certified labs for Montana

Sources

PWSID MT0000200. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Toole County

All Montana utilities

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