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South Chester Water 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
55 people
Connections
26
Water source
Surface water bought from another system
Based in
Chester, MT
County
Liberty
Owner
Private
Hardness
Very hard
The ZIP code it serves

59522

The short answer

1 result is above EPA’s legal limit, and 1 more is above the health goal. The worst: Haloacetic acids (HAA5), above the legal limit. 4 health-based violations since 2016.

What handles it

What was found

Lead and copper: EPA SDWIS monitoring periods ending 2007 to 2024.

Haloacetic acids (HAA5) and total trihalomethanes (TTHM): Montana’s own results, samples taken from Feb. 19, 2020 to Aug. 25, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the legal limit1

Haloacetic acids (HAA5)

Forms or is added in treatment

Above the legal limit

63.3ppb

Highest yearly average, 2020 to 2026

2026 average: 62.3 ppb

Averaged by year, the highest was 63.3 ppb, in 2024, above EPA’s legal limit of 60 ppb. Its highest single sample was 75 ppb. In 2026, the latest year on file, its three samples averaged 62.3 ppb, above the limit. EPA recorded violations for haloacetic acids (HAA5) at this utility in 2024, 2025 and 2026. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 83 ppb, in 2012.

What handles it

No certification claim covers this compound yet.

Above the health goal1

Lead

Comes from pipes, often your own

Above the health goal

2.0ppb

90th percentile, 2022 to 2024

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 limits1

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

74.3ppb

Highest yearly average, 2020 to 2026

2026 average: 65 ppb

Averaged by year, the highest was 74.3 ppb, in 2024, below EPA’s legal limit of 80 ppb. Its highest single sample was 92 ppb. In 2026, the latest year on file, its three samples averaged 65 ppb. 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 84 ppb, in 2012.

What handles it

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

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.”

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 water filters for lead, ranked

Hardness

Very hard, 240 mg/L (14 grains per gallon), at its one sampling point, in 2020.

Hardness is calcium and magnesium. EPA sets no limit for it: it shows up as scale on fixtures and in water heaters, and as soap that won’t lather. USGS calls water above 60 mg/L moderately hard, above 120 hard and above 180 very hard.

Softeners compared at 14 grains per gallon, salt includedSoftener or salt-free conditioner?Montana water hardness, utility by utility

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
Total Haloacetic Acids (HAA5)The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2026 to Sept. 30, 20260.062 MG/LUnaddressed
Total Haloacetic Acids (HAA5)The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2026 to June 30, 20260.063 MG/LArchived
Total Haloacetic Acids (HAA5)The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2025 to March 31, 20250.062 MG/LResolved
Total Haloacetic Acids (HAA5)The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2024 to Dec. 31, 20240.063 MG/LResolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 1 monitoring or reporting violation not shown.

What this report can’t tell you

  • Everything else. Haloacetic acids (HAA5) and total trihalomethanes (TTHM) results here are Montana’s own from 2020 on, with EPA’s national file for 2012 to 2019. South Chester Water Dist’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 Feb. 19, 2020 to Aug. 25, 2026.

Testing your own tap

South Chester Water 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.

No lab Montana certifies is within 75 miles of the area South Chester Water Dist 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 MT0000007. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Liberty County

All Montana utilities

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