What was found in Durham'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 | 3260 µg/L 33% of the EPA limit 10000 µg/L Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 7818 µg/L — TWIN MAPLES NURSING HOME · 100 people · 2019 | 7/7 | SYR4 |
| Nitrate-Nitrite | 3071 µg/L 31% of the EPA limit 10000 µg/L Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 7782 µg/L — TWIN MAPLES NURSING HOME · 100 people · 2019 | 7/7 | SYR4 |
| Copper | 660 µg/L 51% of the EPA limit 1300 µg/L Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019 | 7/7 | SYR4 |
| Fluoride | 70 µg/L 1.8% of the EPA limit 4000 µg/L Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 418 µg/L — BLUE TRAILS WATER ASSOCIATION · 224 people · 2018 | 4/7 | SYR4 |
| Barium | 388.6 µg/L 19% of the EPA limit 2000 µg/L Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019 | 7/7 | SYR4 |
| Nitrite | 166 µg/L 17% of the EPA limit 1000 µg/L Highest in the city: TWIN MAPLES NURSING HOME · 100 people · 2019 | 2/7 | SYR4 |
| Lead | 4 µg/L 27% of the EPA limit 15 µg/L Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 69.75 µg/L — YESHIVA OF WATERBURY-DURHAM CAMPUS · 490 people · 2019 | 7/7 | SYR4 |
| Cyanide | 69 µg/L 35% of the EPA limit 200 µg/L Highest in the city: TWIN MAPLES NURSING HOME · 100 people · 2019 | 1/7 | SYR4 |
| TTHM | 14.785 µg/L 18% of the EPA limit 80 µg/L Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 26.98 µg/L — YESHIVA OF WATERBURY-DURHAM CAMPUS · 490 people · 2019 | 3/7 | SYR4 |
| Total Haloacetic Acids (HAA5) | 4.78 µg/L 8% of the EPA limit 60 µg/L Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 9.575 µg/L — YESHIVA OF WATERBURY-DURHAM CAMPUS · 490 people · 2019 | 3/7 | SYR4 |
| Chloroform | 3 µg/L No EPA limit set Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 7.668 µg/L — YESHIVA OF WATERBURY-DURHAM CAMPUS · 490 people · 2019 | 3/7 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 6.58 µg/L 110% of the EPA limit, at the 95th percentile of samples — 6 µg/L Highest in the city: DURHAM LEXINGTON PLACE DIVISION · 45 people · 2019 | 1/7 | SYR4 |
| Bromodichloromethane | 3.735 µg/L No EPA limit set Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 6.353 µg/L — YESHIVA OF WATERBURY-DURHAM CAMPUS · 490 people · 2019 | 3/7 | SYR4 |
| Gross Alpha, Excl. Radon And U | 5.55196 pCi/L 37% of the EPA limit 15 pCi/L Highest in the city: OLD INDIAN TRAIL · 32 people · 2019 | 3/7 | SYR4 |
| Trichloroacetic Acid | 0.8000 µg/L No EPA limit set Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 5.52 µg/L — TWIN MAPLES NURSING HOME · 100 people · 2019 | 3/7 | SYR4 |
| Dibromochloromethane | 4.03 µg/L No EPA limit set Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 5.08 µg/L — YESHIVA OF WATERBURY-DURHAM CAMPUS · 490 people · 2019 | 3/7 | SYR4 |
| Dichloroacetic Acid | 2.25 µg/L No EPA limit set Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 4.9 µg/L — YESHIVA OF WATERBURY-DURHAM CAMPUS · 490 people · 2019 | 3/7 | SYR4 |
| Combined Uranium | 4.122 µg/L 14% of the EPA limit 30 µg/L Highest in the city: OLD INDIAN TRAIL · 32 people · 2019 | 5/7 | SYR4 |
| Bromoform | 1.8 µg/L No EPA limit set Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019
Highest in the city: 3.46 µg/L — YESHIVA OF WATERBURY-DURHAM CAMPUS · 490 people · 2019 | 3/7 | SYR4 |
| Dibromoacetic Acid | 2.555 µg/L No EPA limit set Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019 | 3/7 | SYR4 |
| Monobromoacetic Acid | 2.175 µg/L No EPA limit set Highest in the city: YESHIVA OF WATERBURY-DURHAM CAMPUS · 490 people · 2019 | 1/7 | SYR4 |
| Arsenic | 1.95 µg/L 20% of the EPA limit 10 µg/L Highest in the city: TWIN MAPLES NURSING HOME · 100 people · 2019 | 3/7 | SYR4 |
| Combined Radium (-226 And -228) | 1.7 pCi/L 34% of the EPA limit 5 pCi/L Highest in the city: DURHAM LEXINGTON PLACE DIVISION · 45 people · 2019 | 2/7 | SYR4 |
| Monochloroacetic Acid | 1.57 µg/L No EPA limit set Highest in the city: YESHIVA OF WATERBURY-DURHAM CAMPUS · 490 people · 2019 | 1/7 | SYR4 |
| Chromium | 1 µg/L 1% of the EPA limit 100 µg/L Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2019 | 1/7 | SYR4 |
| 1,2-Dichloroethane | 0.7730 µg/L 15% of the EPA limit 5 µg/L Highest in the city: TWIN MAPLES NURSING HOME · 100 people · 2019 | 1/7 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: DURHAM CENTER DIVISION · 1,601 people · 2025
Highest in the city: 0.0024 mg/L — BLUE TRAILS WATER ASSOCIATION · 224 people · 2024 | 7/7 | 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 Durham
| Supplier | Population served |
|---|---|
| DURHAM CENTER DIVISION | 1,601 |
| YESHIVA OF WATERBURY-DURHAM CAMPUS | 490 |
| BLUE TRAILS WATER ASSOCIATION | 224 |
| TWIN MAPLES NURSING HOME | 100 |
| DURHAM ELDERLY HOUSING DIVISION | 50 |
| DURHAM LEXINGTON PLACE DIVISION | 45 |
| OLD INDIAN TRAIL | 32 |
Frequently asked questions about Durham tap water
Is Durham tap water safe to drink?
EPA testing detected 27 contaminants in the water serving Durham. 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 Durham?
7 public water suppliers report drinking-water monitoring for Durham, Connecticut to the EPA. Each is listed above with its population served.
What contaminants are in Durham's water?
The contaminants EPA monitoring detected in Durham 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.