Skip to content
TapBuff
ZIP

Basin County Water and Sewer 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
200 people
Connections
109
Water source
Groundwater
Based in
Basin, MT
County
Jefferson
Owner
Public and private
The ZIP code it serves

59631

The short answer

2 results are above the health goal. The worst: Uranium, above the health goal. 1 health-based violation since 2016.

What handles it

What was found

Copper: EPA’s file records a utility’s copper only when it exceeds the action level. The last here was 1.8 ppm, for the period ending June 30, 2016. None since is on file, so it is not counted as a current finding.

Arsenic, fluoride, nitrate, total trihalomethanes (TTHM), haloacetic acids (HAA5) and chromium (total): Montana’s own results, samples taken from March 4, 2020 to Nov. 5, 2025, with EPA’s 2012 to 2019 file for earlier years.

Uranium: EPA’s compliance monitoring file, samples taken from March 17, 2016 to Feb. 14, 2018. Newer results are in the utility’s annual water quality report.

Above the health goal2

Uranium

Comes from the source

Above the health goal

4.0ppb

Highest yearly average, 2016 to 2018

2018, one sample: 4.0 ppb

Averaged by year, the highest was 4.0 ppb, in 2016: below EPA’s legal limit of 30 ppb, but above its health goal of zero. In 2018, the latest year on file, its one sample was 4.0 ppb.

What handles it

Arsenic

Comes from the source

Above the health goal

1.0ppb

Highest yearly average, 2020 to 2025

2025, one sample: 1.0 ppb

Averaged by year, the highest was 1.0 ppb, in 2020: below EPA’s legal limit of 10 ppb, but above its health goal of zero. In 2025, the latest year on file, its one sample was 1.0 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 1.0 ppb, in 2014.

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

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.3ppm

Highest yearly average, 2020 to 2025

2025, one sample: 0.3 ppm

Averaged by year, the highest was 0.3 ppm, in 2020, below EPA’s legal limit of 4.0 ppm. In 2025, the latest year on file, its one sample was 0.3 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.23 ppm, in 2013.

What handles it

Nitrate

Comes from the source

Below EPA’s limits

0.6ppm

Highest sample; found in 5 of 5

2025, one sample: 0.49 ppm

The highest sample, in 2023, was 0.6 ppm, below EPA’s legal limit of 10 ppm. In 2025, the latest year on file, its one sample was 0.49 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.32 ppm, in 2013.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

2.8ppb

Highest yearly average, 2020 to 2025

2025: not found

Averaged by year, the highest was 2.8 ppb, in 2021, below EPA’s legal limit of 80 ppb. 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 9.0 ppb, in 2017.

What handles it

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

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

1.7ppb

Highest yearly average, 2021 to 2024

Averaged by year, the highest was 1.7 ppb, in 2024, below EPA’s legal limit of 60 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 2.3 ppb, in 2017.

What handles it

No certification claim covers this compound yet.

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

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

    For: Uranium, 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
Lead and Copper RuleOCCT/SOWT Treatment Installation/DemonstrationFeb. 8, 2021—Resolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 9 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Arsenic, fluoride, nitrate, total trihalomethanes (TTHM), haloacetic acids (HAA5) and chromium (total) 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. Basin County Water and Sewer 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 March 4, 2020 to Nov. 5, 2025; EPA’s compliance samples are from March 17, 2016 to Feb. 14, 2018.

Testing your own tap

Basin County Water and Sewer 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 3 labs Montana certifies closest to the area Basin County Water and Sewer Dist serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • DPHHS State of Montana Environmental Laboratory

    Helena, MT · about 18 miles

    Certified for bacteria, minerals and other inorganics, organic chemicals

    (406) 444-3444

  • Alpine Analytical

    Helena, MT · about 18 miles

    Certified for bacteria, minerals and other inorganics

    (406) 449-6282

  • Montana Bureau of Mines and Geology

    Butte, MT · about 20 miles

    Certified for minerals and other inorganics

    (406) 496-4747

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 MT0000014. Rebuilt from EPA data on Oct. 18, 2026.

Nearby

All Montana utilities

What to do next