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Tap water quality report

Stonington, ME

EPA monitoring detected 23 contaminants across the 2 water suppliers serving Stonington. A detection doesn't automatically mean the water is unsafe — see the level at the main supplier for each below, with its EPA source and period.

2
water suppliers
727
people served
23
contaminants found
Maine rankings Lead in Maine PFAS in Maine

What was found in Stonington'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.

ContaminantLevel vs EPA limitSuppliersSource
Nitrate
60 µg/L 0.6%
of the EPA limit 10000 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
Highest in the city: 1100 µg/L — STONINGTON MANOR · 44 people · 2019
2/2 SYR4
Nitrate-Nitrite
60 µg/L 0.6%
of the EPA limit 10000 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
Highest in the city: 1070 µg/L — STONINGTON MANOR · 44 people · 2018
2/2 SYR4
Copper
620 µg/L 48%
of the EPA limit 1300 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
2/2 SYR4
Fluoride
465 µg/L 12%
of the EPA limit 4000 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
2/2 SYR4
TTHM
89.98 µg/L 112%
of the EPA limit, at the 95th percentile of samples — 80 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
2/2 SYR4
Chloroform
65 µg/L
No EPA limit set
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
1/2 SYR4
Combined Uranium
27.85 µg/L 93%
of the EPA limit 30 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
Highest in the city: 48.56 µg/L — STONINGTON MANOR · 44 people · 2019
2/2 SYR4
Gross Alpha, Excl. Radon And U
37.025 pCi/L 247%
of the EPA limit, at the 95th percentile of samples — 15 pCi/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
2/2 SYR4
Total Haloacetic Acids (HAA5)
36.5 µg/L 61%
of the EPA limit 60 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
2/2 SYR4
Lead
2.6 µg/L 17%
of the EPA limit 15 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
Highest in the city: 26.11 µg/L — STONINGTON MANOR · 44 people · 2019
2/2 SYR4
Trichloroacetic Acid
25.6 µg/L
No EPA limit set
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
1/2 SYR4
Bromodichloromethane
22.25 µg/L
No EPA limit set
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
2/2 SYR4
Dichloroacetic Acid
14.2 µg/L
No EPA limit set
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
1/2 SYR4
Dibromochloromethane
8.225 µg/L
No EPA limit set
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
2/2 SYR4
Barium
3.365 µg/L 0.2%
of the EPA limit 2000 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
Highest in the city: 5.98 µg/L — STONINGTON MANOR · 44 people · 2018
2/2 SYR4
Bromoform
1.1 µg/L
No EPA limit set
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
Highest in the city: 3.12 µg/L — STONINGTON MANOR · 44 people · 2016
2/2 SYR4
Combined Radium (-226 And -228)
2.1724 pCi/L 43%
of the EPA limit 5 pCi/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
2/2 SYR4
Chromium
2.125 µg/L 2.1%
of the EPA limit 100 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
2/2 SYR4
Dibromoacetic Acid
1.1 µg/L
No EPA limit set
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
Highest in the city: 1.7 µg/L — STONINGTON MANOR · 44 people · 2016
2/2 SYR4
Selenium
1.4 µg/L 2.8%
of the EPA limit 50 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
1/2 SYR4
Toluene
1.4 µg/L 0.1%
of the EPA limit 1000 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
1/2 SYR4
Antimony, Total
0.5300 µg/L 8.8%
of the EPA limit 6 µg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2019
1/2 SYR4
Lead
0.0013 mg/L 8.7%
of the EPA limit 0.0150 mg/L
Main supplier: STONINGTON WATER COMPANY · 683 people · 2025
Highest in the city: 0.0084 mg/L — STONINGTON MANOR · 44 people · 2025
2/2 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 Stonington

SupplierPopulation served
STONINGTON WATER COMPANY 683
STONINGTON MANOR 44

Frequently asked questions about Stonington tap water

Is Stonington tap water safe to drink?

EPA testing detected 23 contaminants in the water serving Stonington. 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 Stonington?

2 public water suppliers report drinking-water monitoring for Stonington, Maine to the EPA. Each is listed above with its population served.

What contaminants are in Stonington's water?

The contaminants EPA monitoring detected in Stonington include Nitrate, Nitrate-Nitrite, Copper, Fluoride, TTHM. 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.