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Dunstable Water Department

What EPA’s and Massachusetts’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
337 people
Connections
106
Water source
Groundwater
Based in
Dunstable, MA
County
Middlesex
Owner
Local government
Hardness
Moderately hard
The ZIP code it serves

01827

The short answer

1 result is above the health goal. The worst: Lead, 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 2020 to 2026.

Copper: EPA’s file records a utility’s copper only when it exceeds the action level. The last here was 2.2 ppm, for the period ending June 30, 1994. None since is on file, so it is not counted as a current finding.

Nitrate, total trihalomethanes (TTHM), haloacetic acids (HAA5), arsenic, chromium (total) and fluoride: Massachusetts’s own results, samples taken from June 9, 2020 to Aug. 11, 2026, with EPA’s 2012 to 2019 file for earlier years.

Uranium: EPA’s compliance monitoring file, samples taken from May 30, 2017 to May 30, 2017. Newer results are in the utility’s annual water quality report.

Above the health goal1

Lead

Comes from pipes, often your own

Above the health goal

1.1ppb

90th percentile, 2026

In the latest period, 9 in 10 homes sampled were at or below 1.1 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 limits3

Nitrate

Comes from the source

Below EPA’s limits

2.9ppm

Highest sample; found in 14 of 14

2026 average: 1.8 ppm

The highest sample, in 2024, was 2.9 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, its two samples averaged 1.8 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 3.0 ppm, in 2018.

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

10ppb

Highest yearly average, 2024 to 2026

Averaged by year, the highest was 10 ppb, in 2026, below EPA’s legal limit of 80 ppb. That was also the latest year on file.

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

3.2ppb

Highest yearly average, 2024 to 2026

2026, one sample: 1.2 ppb

Averaged by year, the highest was 3.2 ppb, in 2024, below EPA’s legal limit of 60 ppb. In 2026, the latest year on file, its one sample was 1.2 ppb.

What handles it

No certification claim covers this compound yet.

4 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Arsenic
  • Chromium (total)
  • Fluoride
  • Uranium

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

Moderately hard, typically 92 mg/L (5.4 grains per gallon), across 2 sampling points, 2015 to 2021.

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 5.4 grains per gallon, salt includedSoftener or salt-free conditioner?Massachusetts water hardness, utility by utility

Violations since 2016

No health-based violations on file with EPA since 2016. There are 3 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Nitrate, total trihalomethanes (TTHM), haloacetic acids (HAA5), arsenic, chromium (total) and fluoride results here are Massachusetts’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. Dunstable Water Department’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; Massachusetts’s results run from June 9, 2020 to Aug. 11, 2026; EPA’s compliance samples are from May 30, 2017 to May 30, 2017.

Testing your own tap

Dunstable Water Department’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 Massachusetts certifies.

The 3 labs Massachusetts certifies closest to the area Dunstable Water Department serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Eurofins Ayer

    Ayer, MA · about 8 miles

    Certified for bacteria, nitrate, minerals and other inorganics

    (978) 391-4428

  • Eurofins Derry

    Derry, NH · about 18 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, PFAS

    (603) 432-3044

  • Nelson Analytical LLC

    Manchester, NH · about 20 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics

    (603) 622-0200

All 81 certified labs for Massachusetts

Sources

PWSID MA2081000. Rebuilt from EPA data on Oct. 18, 2026.

Also in Middlesex County

All Massachusetts utilities

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