What was found in Westminster'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 |
|---|---|---|---|
| Fluoride | 620 µg/L 16% of the EPA limit 4000 µg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019
Highest in the city: 2270 µg/L — BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2017 | 2/3 | SYR4 |
| Nitrate | 150 µg/L 1.5% of the EPA limit 10000 µg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019
Highest in the city: 180 µg/L — BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2019 | 2/3 | SYR4 |
| Nitrate-Nitrite | 150 µg/L 1.5% of the EPA limit 10000 µg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019
Highest in the city: 172.9 µg/L — BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2017 | 2/3 | SYR4 |
| Nitrite | 60 µg/L 6% of the EPA limit 1000 µg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019 | 1/3 | SYR4 |
| Barium | 55.5 µg/L 2.8% of the EPA limit 2000 µg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019 | 2/3 | SYR4 |
| TTHM | 41.925 µg/L 52% of the EPA limit 80 µg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019 | 2/3 | SYR4 |
| Xylenes, Total | 0.6765 µg/L 0% of the EPA limit 10000 µg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019
Highest in the city: 28.165 µg/L — BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2019 | 2/3 | SYR4 |
| Chloroform | 21.725 µg/L No EPA limit set Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019 | 1/3 | SYR4 |
| Lithium | 21.3 µg/L No EPA limit set Main supplier: WESTMINSTER CITY OF · 202,078 people · 2024 | 1/3 | UCMR-5 |
| Bromodichloromethane | 17.95 µg/L No EPA limit set Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019 | 2/3 | SYR4 |
| Total Haloacetic Acids (HAA5) | 17.1 µg/L 29% of the EPA limit 60 µg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019 | 2/3 | SYR4 |
| Dichloroacetic Acid | 11.073 µg/L No EPA limit set Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019 | 1/3 | SYR4 |
| Dibromochloromethane | 9.36 µg/L No EPA limit set Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019 | 2/3 | SYR4 |
| Monochloroacetic Acid | 7.5 µg/L No EPA limit set Highest in the city: BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2017 | 1/3 | SYR4 |
| Bromoform | 1.149 µg/L No EPA limit set Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019
Highest in the city: 6.32 µg/L — BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2019 | 2/3 | SYR4 |
| Chromium | 1 µg/L 1% of the EPA limit 100 µg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019
Highest in the city: 5 µg/L — BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2017 | 2/3 | SYR4 |
| Trichloroacetic Acid | 4.691 µg/L No EPA limit set Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019 | 1/3 | SYR4 |
| Ethylbenzene | 3.925 µg/L 0.6% of the EPA limit 700 µg/L Highest in the city: BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2019 | 1/3 | SYR4 |
| Selenium | 3.19 µg/L 6.4% of the EPA limit 50 µg/L Highest in the city: BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2017 | 1/3 | SYR4 |
| Dibromoacetic Acid | 1.8 µg/L No EPA limit set Main supplier: WESTMINSTER CITY OF · 202,078 people · 2019
Highest in the city: 2.5 µg/L — BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2017 | 2/3 | SYR4 |
| Gross Alpha, Excl. Radon And U | 0.2900 pCi/L 1.9% of the EPA limit 15 pCi/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2018
Highest in the city: 2.2 pCi/L — BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2017 | 2/3 | SYR4 |
| Monobromoacetic Acid | 1.3 µg/L No EPA limit set Highest in the city: BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2017 | 1/3 | SYR4 |
| Combined Uranium | 1.1 µg/L 3.7% of the EPA limit 30 µg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2018 | 1/3 | SYR4 |
| Arsenic | 0.8800 µg/L 8.8% of the EPA limit 10 µg/L Highest in the city: BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2017 | 1/3 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 0.7000 µg/L 12% of the EPA limit 6 µg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2017 | 1/3 | SYR4 |
| Cadmium | 0.1300 µg/L 2.6% of the EPA limit 5 µg/L Highest in the city: BELLEVIEW CHRISTIAN COLLEGE · 460 people · 2017 | 1/3 | SYR4 |
| Lead | 0.0013 mg/L 8.7% of the EPA limit 0.0150 mg/L Main supplier: WESTMINSTER CITY OF · 202,078 people · 2025 | 3/3 | 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 Westminster
| Supplier | Population served |
|---|---|
| WESTMINSTER CITY OF | 202,078 |
| CASA ESTATES MHP | 1,117 |
| BELLEVIEW CHRISTIAN COLLEGE | 460 |
Frequently asked questions about Westminster tap water
Is Westminster tap water safe to drink?
EPA testing detected 27 contaminants in the water serving Westminster. 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 Westminster?
3 public water suppliers report drinking-water monitoring for Westminster, Colorado to the EPA. Each is listed above with its population served.
What contaminants are in Westminster's water?
The contaminants EPA monitoring detected in Westminster include Fluoride, Nitrate, Nitrate-Nitrite, Nitrite, 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.