What was found in Ledyard'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 | 88 µg/L 0.9% of the EPA limit 10000 µg/L Main supplier: GROTON UTILITIES · 30,200 people · 2019
Highest in the city: 6100 µg/L — SCWA, BARRETT DIVISION (BAR) · 300 people · 2019 | 7/9 | SYR4 |
| Nitrate-Nitrite | 93 µg/L 0.9% of the EPA limit 10000 µg/L Main supplier: GROTON UTILITIES · 30,200 people · 2019
Highest in the city: 6009.5 µg/L — SCWA, BARRETT DIVISION (BAR) · 300 people · 2019 | 7/9 | SYR4 |
| Copper | 103 µg/L 7.9% of the EPA limit 1300 µg/L Main supplier: GROTON UTILITIES · 30,200 people · 2019
Highest in the city: 1217 µg/L — SCWA, TOWER-FERRY VIEW DIVISION · 2,567 people · 2019 | 9/9 | SYR4 |
| Fluoride | 1038 µg/L 26% of the EPA limit 4000 µg/L Main supplier: GROTON UTILITIES · 30,200 people · 2019 | 6/9 | SYR4 |
| Barium | 14.75 µg/L 0.7% of the EPA limit 2000 µg/L Main supplier: GROTON UTILITIES · 30,200 people · 2019
Highest in the city: 316.7 µg/L — SCWA, LEDYARD CENTER DIVISION · 652 people · 2018 | 7/9 | SYR4 |
| Chlorite | 190 µg/L 19% of the EPA limit 1000 µg/L Main supplier: GROTON UTILITIES · 30,200 people · 2019 | 1/9 | SYR4 |
| TTHM | 88.86 µg/L 111% of the EPA limit, at the 95th percentile of samples — 80 µg/L Main supplier: GROTON UTILITIES · 30,200 people · 2019
Highest in the city: 98.408 µg/L — LEDYARD WPCA - LEDYARD CENTER · 3,294 people · 2019 | 7/9 | SYR4 |
| Chloroform | 15.715 µg/L No EPA limit set Main supplier: GROTON UTILITIES · 30,200 people · 2019
Highest in the city: 67 µg/L — AQUARION-MYSTIC · 10,788 people · 2019 | 5/9 | SYR4 |
| Total Haloacetic Acids (HAA5) | 36.31 µg/L 61% of the EPA limit 60 µg/L Main supplier: GROTON UTILITIES · 30,200 people · 2019
Highest in the city: 67 µg/L — AQUARION-MYSTIC · 10,788 people · 2019 | 7/9 | SYR4 |
| Lead | 54.8 µg/L 365% of the EPA limit, at the 95th percentile of samples — 15 µg/L Main supplier: GROTON UTILITIES · 30,200 people · 2019 | 8/9 | SYR4 |
| Trichloroacetic Acid | 36 µg/L No EPA limit set Highest in the city: AQUARION-MYSTIC · 10,788 people · 2019 | 2/9 | SYR4 |
| Dichloroacetic Acid | 27 µg/L No EPA limit set Highest in the city: AQUARION-MYSTIC · 10,788 people · 2019 | 2/9 | SYR4 |
| Gross Alpha, Excl. Radon And U | 17.772 pCi/L 118% of the EPA limit, at the 95th percentile of samples — 15 pCi/L Highest in the city: SCWA, TOWER-FERRY VIEW DIVISION · 2,567 people · 2019 | 4/9 | SYR4 |
| Bromodichloromethane | 7.615 µg/L No EPA limit set Main supplier: GROTON UTILITIES · 30,200 people · 2019
Highest in the city: 17 µg/L — AQUARION-MYSTIC · 10,788 people · 2019 | 6/9 | SYR4 |
| Combined Uranium | 16.32 µg/L 54% of the EPA limit 30 µg/L Highest in the city: SCWA, LEDYARD CENTER DIVISION · 652 people · 2019 | 4/9 | SYR4 |
| Combined Radium (-226 And -228) | 5.354 pCi/L 107% of the EPA limit, at the 95th percentile of samples — 5 pCi/L Highest in the city: SCWA, TOWER-FERRY VIEW DIVISION · 2,567 people · 2019 | 2/9 | SYR4 |
| Dibromochloromethane | 1.965 µg/L No EPA limit set Main supplier: GROTON UTILITIES · 30,200 people · 2019
Highest in the city: 4 µg/L — AQUARION-MYSTIC · 10,788 people · 2019 | 6/9 | SYR4 |
| Bromoform | 3.15 µg/L No EPA limit set Highest in the city: SCWA, LEDYARD CENTER DIVISION · 652 people · 2019 | 3/9 | SYR4 |
| Monochloroacetic Acid | 3 µg/L No EPA limit set Highest in the city: AQUARION-MYSTIC · 10,788 people · 2019 | 3/9 | SYR4 |
| Dibromoacetic Acid | 2.41 µg/L No EPA limit set Highest in the city: SCWA, TOWER-FERRY VIEW DIVISION · 2,567 people · 2019 | 4/9 | SYR4 |
| Chromium | 1.95 µg/L 2% of the EPA limit 100 µg/L Highest in the city: SCWA, BARRETT DIVISION (BAR) · 300 people · 2018 | 2/9 | SYR4 |
| Monobromoacetic Acid | 1.3 µg/L No EPA limit set Highest in the city: SCWA, TOWER-FERRY VIEW DIVISION · 2,567 people · 2019 | 2/9 | SYR4 |
| Thallium, Total | 1.3 µg/L 65% of the EPA limit 2 µg/L Highest in the city: SCWA, TOWER-FERRY VIEW DIVISION · 2,567 people · 2019 | 1/9 | SYR4 |
| Cadmium | 1 µg/L 20% of the EPA limit 5 µg/L Highest in the city: AQUARION-MYSTIC · 10,788 people · 2019 | 1/9 | SYR4 |
| Arsenic | 0.6000 µg/L 6% of the EPA limit 10 µg/L Highest in the city: SCWA, TOWER-FERRY VIEW DIVISION · 2,567 people · 2019 | 1/9 | SYR4 |
| Toluene | 0.5800 µg/L 0.1% of the EPA limit 1000 µg/L Highest in the city: SCWA, TOWER-FERRY VIEW DIVISION · 2,567 people · 2019 | 1/9 | SYR4 |
| Dichloromethane | 0.5500 µg/L 11% of the EPA limit 5 µg/L Highest in the city: SCWA, TOWER-FERRY VIEW DIVISION · 2,567 people · 2019 | 1/9 | SYR4 |
| Beryllium, Total | 0.4850 µg/L 12% of the EPA limit 4 µg/L Highest in the city: SCWA, TOWER-FERRY VIEW DIVISION · 2,567 people · 2019 | 4/9 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: GROTON UTILITIES · 30,200 people · 2025
Highest in the city: 0.0136 mg/L — SCWA, BARRETT DIVISION (BAR) · 300 people · 2023 | 9/9 | LCR |
| PFBS | 0.0040 µg/L No EPA limit set Highest in the city: AQUARION-MYSTIC · 10,788 people · 2025 | 1/9 | UCMR-5 |
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 Ledyard
| Supplier | Population served |
|---|---|
| GROTON UTILITIES | 30,200 |
| AQUARION-MYSTIC | 10,788 |
| LEDYARD WPCA - LEDYARD CENTER | 3,294 |
| SCWA, TOWER-FERRY VIEW DIVISION | 2,567 |
| LEDYARD WPCA, GALES FERRY SYSTEM | 2,369 |
| SCWA, LEDYARD CENTER DIVISION | 652 |
| SCWA, BARRETT DIVISION (BAR) | 300 |
| SCWA, CHRISWOOD DIVISION (CWD) | 164 |
| ASH WATER COMPANY, LLC | 108 |
Frequently asked questions about Ledyard tap water
Is Ledyard tap water safe to drink?
EPA testing detected 30 contaminants in the water serving Ledyard. 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 Ledyard?
9 public water suppliers report drinking-water monitoring for Ledyard, Connecticut to the EPA. Each is listed above with its population served.
What contaminants are in Ledyard's water?
The contaminants EPA monitoring detected in Ledyard include Nitrate, Nitrate-Nitrite, Copper, Fluoride, Barium. 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.