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Flathead County Water Dist 101

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
210 people
Connections
96
Water source
Groundwater
Based in
Columbia Falls, MT
County
Flathead
Owner
Private
The ZIP code it serves

59912

The short answer

3 results are above the health goal. The worst: Arsenic, above the health goal. No health-based violations on file since 2016.

What handles it

What was found

Lead and copper: EPA SDWIS monitoring periods ending 2003 to 2024.

Arsenic, uranium, fluoride, nitrate, chromium (total) and total trihalomethanes (TTHM): Montana’s own results, samples taken from Jan. 3, 2022 to April 16, 2025, with EPA’s 2012 to 2019 file for earlier years.

Above the health goal3

Arsenic

Comes from the source

Above the health goal

1.0ppb

Highest yearly average, 2022 to 2025

2025: not found

Averaged by year, the highest was 1.0 ppb, in 2022: below EPA’s legal limit of 10 ppb, but above its health goal of zero. In 2025, the latest year on file, it wasn’t found in its one sample. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.5 ppb, in 2013.

What handles it

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

Lead

Comes from pipes, often your own

Above the health goal

1.0ppb

90th percentile, 2022 to 2024

In the latest period, 9 in 10 homes sampled were at or below 1.0 ppb, below EPA’s action level of 15 ppb. The action level drops to 10 ppb on Nov. 1, 2027. EPA’s health goal for lead is zero.

What handles it

Uranium

Comes from the source

Above the health goal

1.6ppb

Highest yearly average, 2022

Averaged by year, the highest was 1.6 ppb, in 2022: below EPA’s legal limit of 30 ppb, but above its health goal of zero. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 2.0 ppb, in 2016.

What handles it

Below EPA’s limits2

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.1ppm

Highest yearly average, 2022 to 2025

Averaged by year, the highest was 0.1 ppm, in 2025, below EPA’s legal limit of 4.0 ppm. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.13 ppm, in 2013.

What handles it

Nitrate

Comes from the source

Below EPA’s limits

0.08ppm

Highest sample; found in 2 of 2

2025, one sample: 0.02 ppm

The highest sample, in 2022, was 0.08 ppm, below EPA’s legal limit of 10 ppm. In 2025, the latest year on file, its one sample was 0.02 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.02 ppm, in 2013.

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)
  • Total trihalomethanes (TTHM)

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

    Claims: Arsenic (Pentavalent)<=50 ppb Reduction, Lead Reduction

    For: Arsenic, Lead

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

  • NSF/ANSI 58

    Claims: Arsenic (Pentavalent)<=50 ppb Reduction, Lead Reduction, Uranium

    For: Arsenic, Lead, Uranium

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

At the tap, or for the whole house?

Lead and copper usually come from pipes and fixtures inside or near your home. A whole-house system sits where water enters, so it cannot catch what your own plumbing adds after it. For those, the filter that counts is the one at the tap. 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

The best water filters for lead, ranked

Violations since 2016

No health-based violations on file with EPA since 2016. There are 6 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Arsenic, uranium, fluoride, nitrate, chromium (total) and total trihalomethanes (TTHM) results here are Montana’s own from 2022 on, with EPA’s national file for 2012 to 2019. Flathead County Water Dist 101’s own annual report, which it must send you every year, has 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. 3, 2022 to April 16, 2025.

Testing your own tap

Flathead County Water Dist 101’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.

The lab Montana certifies closest to the area Flathead County Water Dist 101 serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Montana Environmental Laboratory

    Kalispell, MT · about 16 miles

    Certified for bacteria, minerals and other inorganics

    (406) 755-2131

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 MT0000184. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Flathead County

All Montana utilities

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