What was found in Mashantucket'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 | 1310 µg/L 13% of the EPA limit 10000 µg/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2019 | 1/1 | SYR4 |
| Nitrite | 590 µg/L 59% of the EPA limit 1000 µg/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2019 | 1/1 | SYR4 |
| TTHM | 109.59 µg/L 137% of the EPA limit, at the 95th percentile of samples — 80 µg/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2019 | 1/1 | SYR4 |
| Barium | 63.65 µg/L 3.2% of the EPA limit 2000 µg/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2019 | 1/1 | SYR4 |
| Total Haloacetic Acids (HAA5) | 36.515 µg/L 61% of the EPA limit 60 µg/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2019 | 1/1 | SYR4 |
| Gross Alpha, Excl. Radon And U | 10.6 pCi/L 71% of the EPA limit 15 pCi/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2018 | 1/1 | SYR4 |
| Glyphosate | 6 µg/L 0.9% of the EPA limit 700 µg/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2019 | 1/1 | SYR4 |
| Cyanide | 5 µg/L 2.5% of the EPA limit 200 µg/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2019 | 1/1 | SYR4 |
| Arsenic | 1.95 µg/L 20% of the EPA limit 10 µg/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2019 | 1/1 | SYR4 |
| Picloram | 0.1250 µg/L 0% of the EPA limit 500 µg/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2019 | 1/1 | SYR4 |
| Pentachlorophenol | 0.0650 µg/L 6.5% of the EPA limit 1 µg/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2019 | 1/1 | SYR4 |
| Pfpea | 0.0191 µg/L No EPA limit set Main supplier: Mashantucket Pequot Water System · 22,171 people · 2024 | 1/1 | UCMR-5 |
| Pfhxa | 0.0099 µg/L No EPA limit set Main supplier: Mashantucket Pequot Water System · 22,171 people · 2024 | 1/1 | UCMR-5 |
| PFOA | 0.0074 µg/L No EPA limit set Main supplier: Mashantucket Pequot Water System · 22,171 people · 2024 | 1/1 | UCMR-5 |
| Pfba | 0.0065 µg/L No EPA limit set Main supplier: Mashantucket Pequot Water System · 22,171 people · 2024 | 1/1 | UCMR-5 |
| PFBS | 0.0036 µg/L No EPA limit set Main supplier: Mashantucket Pequot Water System · 22,171 people · 2024 | 1/1 | UCMR-5 |
| Pfhpa | 0.0036 µg/L No EPA limit set Main supplier: Mashantucket Pequot Water System · 22,171 people · 2024 | 1/1 | UCMR-5 |
| Lead | 0.0010 mg/L 6.7% of the EPA limit 0.0150 mg/L Main supplier: Mashantucket Pequot Water System · 22,171 people · 2025 | 1/1 | LCR |
Water suppliers serving Mashantucket
| Supplier | Population served |
|---|---|
| Mashantucket Pequot Water System | 22,171 |
Frequently asked questions about Mashantucket tap water
Is Mashantucket tap water safe to drink?
EPA testing detected 18 contaminants in the water serving Mashantucket. 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 Mashantucket?
1 public water supplier report drinking-water monitoring for Mashantucket, Connecticut to the EPA. Each is listed above with its population served.
What contaminants are in Mashantucket's water?
The contaminants EPA monitoring detected in Mashantucket include Nitrate, Nitrite, TTHM, 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.