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Tap water quality report

Columbia, CT

EPA monitoring detected 12 contaminants across the 4 water suppliers serving Columbia. A detection doesn't automatically mean the water is unsafe — see the highest level found for each below, with its EPA source and period.

4
water suppliers
180
people served
12
contaminants found
Connecticut rankings Lead in Connecticut PFAS in Connecticut

What was found in Columbia'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
1500 µg/L 15%
of the EPA limit 10000 µg/L
 4/4 SYR4
Nitrate-Nitrite
1500 µg/L 15%
of the EPA limit 10000 µg/L
 4/4 SYR4
Copper
1140 µg/L 88%
of the EPA limit 1300 µg/L
 4/4 SYR4
Fluoride
800 µg/L 20%
of the EPA limit 4000 µg/L
 4/4 SYR4
Lead
24 µg/L 160%
of the EPA limit, in the worst sample — 15 µg/L
 4/4 SYR4
Combined Uranium
10.5 µg/L 35%
of the EPA limit 30 µg/L
 3/4 SYR4
Barium
10 µg/L 0.5%
of the EPA limit 2000 µg/L
 3/4 SYR4
Gross Alpha, Excl. Radon And U
5.1 pCi/L 34%
of the EPA limit 15 pCi/L
 3/4 SYR4
Combined Radium (-226 And -228)
3.4 pCi/L 68%
of the EPA limit 5 pCi/L
 1/4 SYR4
Di(2-ethylhexyl) Phthalate
1.9 µg/L 32%
of the EPA limit 6 µg/L
 2/4 SYR4
Arsenic
1 µg/L 10%
of the EPA limit 10 µg/L
 2/4 SYR4
Lead
0.0084 mg/L 56%
of the EPA limit 0.0150 mg/L
 4/4 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 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 Columbia

SupplierPopulation served
HILLSIDE CONDOMINIUMS 96
CTWC - COLUMBIA HEIGHTS DIV. 32
WOODLAND TERRACE 27
DARTMOUTH VILLAGE ELDERLY HOUSING 25

Frequently asked questions about Columbia tap water

Is Columbia tap water safe to drink?

EPA testing detected 12 contaminants in the water serving Columbia. 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 Columbia?

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

What contaminants are in Columbia's water?

The contaminants EPA monitoring detected in Columbia include Nitrate, Nitrate-Nitrite, Copper, Fluoride, Lead. 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.