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Tap water quality report

Mashantucket, CT

EPA monitoring detected 18 contaminants across the 1 water supplier serving Mashantucket. A detection doesn't automatically mean the water is unsafe — see the highest level found for each below, with its EPA source and period.

1
water supplier
22,171
people served
18
contaminants found
Connecticut rankings Lead in Connecticut PFAS in Connecticut

What was found in Mashantucket's water

The highest level seen across the city's suppliers, the EPA limit for each, and where the figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Nitrate
1310 µg/L 13%
of the EPA limit 10000 µg/L
 1/1 SYR4
Nitrite
590 µg/L 59%
of the EPA limit 1000 µg/L
 1/1 SYR4
TTHM
140 µg/L 175%
of the EPA limit, in the worst sample — 80 µg/L
 1/1 SYR4
Barium
65 µg/L 3.3%
of the EPA limit 2000 µg/L
 1/1 SYR4
Total Haloacetic Acids (HAA5)
48 µg/L 80%
of the EPA limit 60 µg/L
 1/1 SYR4
Gross Alpha, Excl. Radon And U
10.6 pCi/L 71%
of the EPA limit 15 pCi/L
 1/1 SYR4
Glyphosate
6 µg/L 0.9%
of the EPA limit 700 µg/L
 1/1 SYR4
Cyanide
5 µg/L 2.5%
of the EPA limit 200 µg/L
 1/1 SYR4
Arsenic
2 µg/L 20%
of the EPA limit 10 µg/L
 1/1 SYR4
Picloram
0.1250 µg/L 0%
of the EPA limit 500 µg/L
 1/1 SYR4
Pentachlorophenol
0.0650 µg/L 6.5%
of the EPA limit 1 µg/L
 1/1 SYR4
Pfpea
0.0191 µg/L
No EPA limit set
 1/1 UCMR-5
Pfhxa
0.0099 µg/L
No EPA limit set
 1/1 UCMR-5
PFOA
0.0074 µg/L
No EPA limit set
 1/1 UCMR-5
Pfba
0.0065 µg/L
No EPA limit set
 1/1 UCMR-5
PFBS
0.0036 µg/L
No EPA limit set
 1/1 UCMR-5
Pfhpa
0.0036 µg/L
No EPA limit set
 1/1 UCMR-5
Lead
0.0010 mg/L 6.7%
of the EPA limit 0.0150 mg/L
 1/1 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 single worst sample on record — 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 Mashantucket

SupplierPopulation 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 highest level found 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.