Is Charlestown, NH Tap Water Safe? Quality & Contaminants

What was found in Charlestown's water

The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.

Contaminant	Level vs EPA limit	Suppliers	Source
Nitrate	1395 µg/L 14% of the EPA limit 10000 µg/L Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019 Highest in the city: 4600 µg/L — CONNECTICUT RIVER MHP · 50 people · 2019	2/4	SYR4
Copper	560 µg/L 43% of the EPA limit 1300 µg/L Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019	4/4	SYR4
Fluoride	218.5 µg/L 5.5% of the EPA limit 4000 µg/L Highest in the city: MEADOWVIEW APTS · 58 people · 2019	2/4	SYR4
Barium	6.65 µg/L 0.3% of the EPA limit 2000 µg/L Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019 Highest in the city: 62.85 µg/L — WINDY ACRES · 180 people · 2019	4/4	SYR4
Total Haloacetic Acids (HAA5)	9.375 µg/L 16% of the EPA limit 60 µg/L Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019	1/4	SYR4
TTHM	9.195 µg/L 11% of the EPA limit 80 µg/L Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019	1/4	SYR4
Lead	7.6 µg/L 51% of the EPA limit 15 µg/L Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019	3/4	SYR4
Chloroform	6.655 µg/L No EPA limit set Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019	1/4	SYR4
Dichloroacetic Acid	5 µg/L No EPA limit set Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019	1/4	SYR4
Combined Radium (-226 And -228)	1.03 pCi/L 21% of the EPA limit 5 pCi/L Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2017 Highest in the city: 4.695 pCi/L — WINDY ACRES · 180 people · 2015	3/4	SYR4
Arsenic	1.095 µg/L 11% of the EPA limit 10 µg/L Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019 Highest in the city: 4.46 µg/L — MEADOWVIEW APTS · 58 people · 2019	2/4	SYR4
Trichloroacetic Acid	4.375 µg/L No EPA limit set Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019	1/4	SYR4
Bromodichloromethane	2.855 µg/L No EPA limit set Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019	1/4	SYR4
Dibromochloromethane	1.5 µg/L No EPA limit set Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019	1/4	SYR4
Bromoform	1.1 µg/L No EPA limit set Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2019	1/4	SYR4
Combined Uranium	0.7000 µg/L 2.3% of the EPA limit 30 µg/L Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2017 Highest in the city: 0.9000 µg/L — MEADOWVIEW APTS · 58 people · 2014	3/4	SYR4
Gross Alpha, Excl. Radon And U	0.4800 pCi/L 3.2% of the EPA limit 15 pCi/L Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2017 Highest in the city: 0.7000 pCi/L — MEADOWVIEW APTS · 58 people · 2014	4/4	SYR4
Lead	0.0190 mg/L 127% above the EPA limit of 0.0150 mg/L Main supplier: CHARLESTOWN WATER WORKS · 2,850 people · 2024	2/4	LCR

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of the system's samples — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately. These are the utilities' own EPA-reported results, not a city-wide average. A detection means the lab measured the substance — it isn't the same as exceeding a legal limit. Hover a source tag to see the EPA program and years behind each figure.

Water suppliers serving Charlestown

Supplier	Population served
CHARLESTOWN WATER WORKS	2,850
WINDY ACRES	180
MEADOWVIEW APTS	58
CONNECTICUT RIVER MHP	50

Frequently asked questions about Charlestown tap water

Is Charlestown tap water safe to drink?

EPA testing detected 18 contaminants in the water serving Charlestown. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.

How many water suppliers serve Charlestown?

4 public water suppliers report drinking-water monitoring for Charlestown, New Hampshire to the EPA. Each is listed above with its population served.

What contaminants are in Charlestown's water?

The contaminants EPA monitoring detected in Charlestown include Nitrate, Copper, Fluoride, Barium, Total Haloacetic Acids (HAA5). The full list, with the level at the main supplier and the data source, is in the table above.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.