Skip to content
TapBuff
ZIP

Charlestown Water Works

What EPA’s and CDC’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
2,850 people
Connections
1,250
Water source
Groundwater
Based in
Charlestown, NH
County
Sullivan
Owner
Local government
The ZIP code it serves

03603

The short answer

1 result is above EPA’s legal limit, and 2 more are above the health goal. The worst: Lead, above the action level. No health-based violations on file since 2016.

What handles it

What was found

Lead and copper: EPA SDWIS monitoring periods ending 2024.

Arsenic, nitrate, total trihalomethanes (TTHM) and haloacetic acids (HAA5): New Hampshire’s yearly averages per water system, as CDC’s Environmental Public Health Tracking Network publishes them, 2020 to 2023, with EPA’s 2012 to 2019 file for earlier years.

Uranium, chromium (total) and fluoride: EPA’s compliance monitoring file, samples taken from May 5, 2016 to July 24, 2019. Newer results are in the utility’s annual water quality report.

Above the legal limit1

Lead

Comes from pipes, often your own

Above the action level

19ppb

90th percentile, 2024

In the latest period, 9 in 10 homes sampled were at or below 19 ppb, above EPA’s action level of 15 ppb. The action level drops to 10 ppb on Nov. 1, 2027, and this result is at or above that. EPA’s health goal for lead is zero.

What handles it

Above the health goal2

Arsenic

Comes from the source

Above the health goal

1.2ppb

Highest yearly average, 2022

Averaged by year, the highest was 1.2 ppb, in 2022: below EPA’s legal limit of 10 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 0.37 ppb, in 2019.

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

0.7ppb

Highest yearly average, 2016 to 2017

Averaged by year, the highest was 0.7 ppb, in 2017: below EPA’s legal limit of 30 ppb, but above its health goal of zero. That was also the latest year on file.

What handles it

Below EPA’s limits3

Nitrate

Comes from the source

Below EPA’s limits

0.85ppm

Highest yearly average, 2020 to 2023

2023 average: 0.75 ppm

Averaged by year, the highest was 0.85 ppm, in 2021, below EPA’s legal limit of 10 ppm. In 2023, the latest year on file, it averaged 0.75 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 1.4 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

6.3ppb

Highest yearly average, 2020 to 2023

2023 average: 5.6 ppb

Averaged by year, the highest was 6.3 ppb, in 2020, below EPA’s legal limit of 80 ppb. In 2023, the latest year on file, it averaged 5.6 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 9.2 ppb, in 2015.

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

2.1ppb

Highest yearly average, 2020 to 2023

2023 average: 2.1 ppb

Averaged by year, the highest was 2.1 ppb, in 2020, below EPA’s legal limit of 60 ppb. In 2023, the latest year on file, it averaged 2.1 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 9.3 ppb, in 2018.

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)
  • Fluoride

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

    For: Lead, Arsenic

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

  • NSF/ANSI 58

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

    For: Lead, Arsenic, 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 water filters for lead, ranked

The best reverse osmosis systems, ranked

Violations since 2016

No health-based violations on file with EPA since 2016. There are 8 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Arsenic, nitrate, total trihalomethanes (TTHM) and haloacetic acids (HAA5) results here are New Hampshire’s yearly averages as CDC publishes them, from 2020 on, with EPA’s national file for 2012 to 2019. Uranium, chromium (total) and fluoride come from EPA’s file alone, which ends in 2019. Charlestown Water Works’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; CDC’s yearly averages for New Hampshire cover 2020 to 2023; EPA’s compliance samples are from May 5, 2016 to July 24, 2019.

Testing your own tap

Charlestown Water Works’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 New Hampshire certifies.

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

  • Nelson Analytical Lab - Keene Division

    Swanzey, NH · about 20 miles

    Certified for bacteria

    (603) 357-2577

  • Keene City Laboratory

    Swanzey, NH · about 27 miles

    Certified for bacteria

    (603) 357-9836

  • Endyne Inc.

    Lebanon, NH · about 28 miles

    Certified for bacteria, nitrate

    (603) 678-4891

All 63 certified labs for New Hampshire

Sources

PWSID NH0411010. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Sullivan County

All New Hampshire utilities

What to do next