What was found in Denver'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 |
|---|---|---|---|
| Fluoride | 1080 µg/L 27% of the EPA limit 4000 µg/L | 1/4 | SYR4 |
| Nitrate | 660 µg/L 6.6% of the EPA limit 10000 µg/L | 1/4 | SYR4 |
| Nitrate-Nitrite | 290 µg/L 2.9% of the EPA limit 10000 µg/L | 1/4 | SYR4 |
| Barium | 50 µg/L 2.5% of the EPA limit 2000 µg/L | 1/4 | SYR4 |
| TTHM | 41.64 µg/L 52% of the EPA limit 80 µg/L | 1/4 | SYR4 |
| Total Haloacetic Acids (HAA5) | 38 µg/L 63% of the EPA limit 60 µg/L | 1/4 | SYR4 |
| Chloroform | 30.2 µg/L No EPA limit set | 1/4 | SYR4 |
| Cyanide | 25 µg/L 13% of the EPA limit 200 µg/L | 1/4 | SYR4 |
| Dichloroacetic Acid | 17.7 µg/L No EPA limit set | 1/4 | SYR4 |
| Bromodichloromethane | 11.6 µg/L No EPA limit set | 1/4 | SYR4 |
| Lithium | 10.8 µg/L No EPA limit set | 1/4 | UCMR-5 |
| Trichloroacetic Acid | 9.9 µg/L No EPA limit set | 1/4 | SYR4 |
| Selenium | 6.8 µg/L 14% of the EPA limit 50 µg/L | 1/4 | SYR4 |
| Combined Uranium | 6.3 µg/L 21% of the EPA limit 30 µg/L | 1/4 | SYR4 |
| Dibromochloromethane | 6 µg/L No EPA limit set | 1/4 | SYR4 |
| Monochloroacetic Acid | 4.9 µg/L No EPA limit set | 1/4 | SYR4 |
| Chromium | 4 µg/L 4% of the EPA limit 100 µg/L | 1/4 | SYR4 |
| Monobromoacetic Acid | 3.2 µg/L No EPA limit set | 1/4 | SYR4 |
| Gross Beta Particle Activity | 3 pCi/L No EPA limit set | 1/4 | SYR4 |
| Combined Radium (-226 And -228) | 2 pCi/L 40% of the EPA limit 5 pCi/L | 1/4 | SYR4 |
| Gross Alpha, Excl. Radon And U | 2 pCi/L 13% of the EPA limit 15 pCi/L | 1/4 | SYR4 |
| Dibromoacetic Acid | 1.7 µg/L No EPA limit set | 1/4 | SYR4 |
| Arsenic | 1.2 µg/L 12% of the EPA limit 10 µg/L | 1/4 | SYR4 |
| Bromoform | 1 µg/L No EPA limit set | 1/4 | SYR4 |
| Carbon Tetrachloride | 0.5000 µg/L 10% of the EPA limit 5 µg/L | 1/4 | SYR4 |
| Antimony, Total | 0.2800 µg/L 4.7% of the EPA limit 6 µg/L | 1/4 | SYR4 |
| 2,4-D | 0.1000 µg/L 0.1% of the EPA limit 70 µg/L | 1/4 | SYR4 |
| Cadmium | 0.1000 µg/L 2% of the EPA limit 5 µg/L | 1/4 | SYR4 |
| Mercury | 0.0700 µg/L 3.5% of the EPA limit 2 µg/L | 1/4 | SYR4 |
| Beryllium, Total | 0.0600 µg/L 1.5% of the EPA limit 4 µg/L | 1/4 | SYR4 |
| Thallium, Total | 0.0600 µg/L 3% of the EPA limit 2 µg/L | 1/4 | SYR4 |
| Lead | 0.0090 mg/L 60% of the EPA limit 0.0150 mg/L | 4/4 | LCR |
Water suppliers serving Denver
| Supplier | Population served |
|---|---|
| DENVER WATER BOARD | 1,287,000 |
| CHERRY CREEK VALLEY WSD | 22,000 |
| ADVENIR FRENCH QUARTER | 3,447 |
| GARDEN MEADOWS | 250 |
Frequently asked questions about Denver tap water
Is Denver tap water safe to drink?
EPA testing detected 32 contaminants in the water serving Denver. 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 Denver?
4 public water suppliers report drinking-water monitoring for Denver, Colorado to the EPA. Each is listed above with its population served.
What contaminants are in Denver's water?
The contaminants EPA monitoring detected in Denver include Fluoride, Nitrate, Nitrate-Nitrite, Barium, 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.