What was found in Thornton's water
The highest level seen across the city's suppliers, the EPA limit for each, and where the figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate-Nitrite | 1200 µg/L 12% of the EPA limit 10000 µg/L | 1/8 | SYR4 |
| Nitrate | 1160 µg/L 12% of the EPA limit 10000 µg/L | 1/8 | SYR4 |
| Fluoride | 910 µg/L 23% of the EPA limit 4000 µg/L | 1/8 | SYR4 |
| Nitrite | 650 µg/L 65% of the EPA limit 1000 µg/L | 1/8 | SYR4 |
| TTHM | 78.14 µg/L 98% of the EPA limit 80 µg/L | 1/8 | SYR4 |
| Barium | 52.5 µg/L 2.6% of the EPA limit 2000 µg/L | 1/8 | SYR4 |
| Total Haloacetic Acids (HAA5) | 44 µg/L 73% of the EPA limit 60 µg/L | 1/8 | SYR4 |
| Lithium | 34 µg/L No EPA limit set | 1/8 | UCMR-5 |
| Chloroform | 27 µg/L No EPA limit set | 1/8 | SYR4 |
| Bromodichloromethane | 25.4 µg/L No EPA limit set | 1/8 | SYR4 |
| Dibromochloromethane | 18.8 µg/L No EPA limit set | 1/8 | SYR4 |
| Dichloroacetic Acid | 16.1 µg/L No EPA limit set | 1/8 | SYR4 |
| Trichloroacetic Acid | 10 µg/L No EPA limit set | 1/8 | SYR4 |
| Bromoform | 7.5 µg/L No EPA limit set | 1/8 | SYR4 |
| Combined Uranium | 7.4 µg/L 25% of the EPA limit 30 µg/L | 1/8 | SYR4 |
| Gross Beta Particle Activity | 5.86 pCi/L No EPA limit set | 1/8 | SYR4 |
| Dibromoacetic Acid | 5.64 µg/L No EPA limit set | 1/8 | SYR4 |
| Gross Alpha, Excl. Radon And U | 2.7 pCi/L 18% of the EPA limit 15 pCi/L | 1/8 | SYR4 |
| Chromium | 1.8 µg/L 1.8% of the EPA limit 100 µg/L | 1/8 | SYR4 |
| Bromate | 1.6 µg/L 16% of the EPA limit 10 µg/L | 1/8 | SYR4 |
| Monobromoacetic Acid | 1.1 µg/L No EPA limit set | 1/8 | SYR4 |
| Arsenic | 0.9300 µg/L 9.3% of the EPA limit 10 µg/L | 1/8 | SYR4 |
| Combined Radium (-226 And -228) | 0.8300 pCi/L 17% of the EPA limit 5 pCi/L | 1/8 | SYR4 |
| Antimony, Total | 0.2700 µg/L 4.5% of the EPA limit 6 µg/L | 1/8 | SYR4 |
| Pfhxa | 0.0126 µg/L No EPA limit set | 1/8 | UCMR-5 |
| Pfpea | 0.0124 µg/L No EPA limit set | 1/8 | UCMR-5 |
| Pfba | 0.0104 µg/L No EPA limit set | 1/8 | UCMR-5 |
| PFBS | 0.0081 µg/L No EPA limit set | 1/8 | UCMR-5 |
| PFOA | 0.0071 µg/L No EPA limit set | 1/8 | UCMR-5 |
| PFHXS | 0.0059 µg/L No EPA limit set | 1/8 | UCMR-5 |
| PFOS | 0.0050 µg/L No EPA limit set | 1/8 | UCMR-5 |
| Pfhpa | 0.0037 µg/L No EPA limit set | 1/8 | UCMR-5 |
| Lead | 0.0030 mg/L 20% of the EPA limit 0.0150 mg/L | 8/8 | LCR |
Water suppliers serving Thornton
| Supplier | Population served |
|---|---|
| THORNTON CITY OF | 226,465 |
| WOODLAND HILLS MHC | 1,740 |
| REDWOOD ESTATES | 1,500 |
| THE GROVE AT ALTA RIDGE | 1,300 |
| FRIENDLY VILLAGE OF THE ROCKIES | 1,046 |
| AVILLA EASTLAKE | 410 |
| CHAPARRAL VILLAGE MHP | 303 |
| THORNTON ESTATES | 300 |
Frequently asked questions about Thornton tap water
Is Thornton tap water safe to drink?
EPA testing detected 33 contaminants in the water serving Thornton. 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 Thornton?
8 public water suppliers report drinking-water monitoring for Thornton, Colorado to the EPA. Each is listed above with its population served.
What contaminants are in Thornton's water?
The contaminants EPA monitoring detected in Thornton include Nitrate-Nitrite, Nitrate, Fluoride, Nitrite, TTHM. 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.