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Eagle Ridge Estates Co W and S Dist

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
115 people
Connections
47
Water source
Groundwater
Based in
Kalispell, MT
County
Flathead
Owner
Local government
The ZIP code it serves

59901

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 2007 to 2025.

Arsenic, fluoride, nitrate, chromium (total) and total trihalomethanes (TTHM): Montana’s own results, samples taken from April 8, 2020 to Feb. 5, 2024, with EPA’s 2012 to 2019 file for earlier years.

Uranium: EPA’s compliance monitoring file, samples taken from Nov. 18, 2013 to March 3, 2017. Newer results are in the utility’s annual water quality report.

Above the health goal3

Arsenic

Comes from the source

Above the health goal

7.5ppb

Highest yearly average, 2020 to 2023

2023, one sample: 6.0 ppb

Averaged by year, the highest was 7.5 ppb, in 2020: below EPA’s legal limit of 10 ppb, but above its health goal of zero. Its highest single sample was 10 ppb. In 2023, the latest year on file, its one sample was 6.0 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 11 ppb, in 2012.

What handles it

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

Uranium

Comes from the source

Above the health goal

9.5ppb

Highest yearly average, 2013 to 2017

2017, one sample: 7.0 ppb

Averaged by year, the highest was 9.5 ppb, in 2016: below EPA’s legal limit of 30 ppb, but above its health goal of zero. Its highest single sample was 11 ppb. In 2017, the latest year on file, its one sample was 7.0 ppb.

What handles it

Lead

Comes from pipes, often your own

Above the health goal

2.0ppb

90th percentile, 2023 to 2025

In the latest period, 9 in 10 homes sampled were at or below 2.0 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

Below EPA’s limits2

Fluoride

Forms or is added in treatment

Below EPA’s limits

1.8ppm

Highest yearly average, 2020 to 2023

2023, one sample: 1.3 ppm

Averaged by year, the highest was 1.8 ppm, in 2020, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 2.3 ppm. In 2023, the latest year on file, its one sample was 1.3 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 1.8 ppm, in 2012.

What handles it

Nitrate

Comes from the source

Below EPA’s limits

0.73ppm

Highest sample; found in 2 of 2

2023, one sample: 0.73 ppm

The highest sample, in 2023, was 0.73 ppm, below EPA’s legal limit of 10 ppm. That was also the latest year on file, and its one sample was 0.73 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.68 ppm, in 2014.

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, Uranium, Lead Reduction

    For: Arsenic, Uranium, Lead

    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.

What this report can’t tell you

  • Everything else. Arsenic, fluoride, nitrate, chromium (total) and total trihalomethanes (TTHM) results here are Montana’s own from 2020 on, with EPA’s national file for 2012 to 2019. Uranium comes from EPA’s file alone, which ends in 2019. Eagle Ridge Estates Co W and S Dist’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 April 8, 2020 to Feb. 5, 2024; EPA’s compliance samples are from Nov. 18, 2013 to March 3, 2017.

Testing your own tap

Eagle Ridge Estates Co W and S Dist’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 2 labs Montana certifies closest to the area Eagle Ridge Estates Co W and S Dist 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 · under a mile

    Certified for bacteria, minerals and other inorganics

    (406) 755-2131

  • Mission Mountain Laboratories

    Ravalli, MT · about 65 miles

    Certified for bacteria

    (406) 370-1089

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 MT0004475. Rebuilt from EPA data on Oct. 18, 2026.