Is Westminster, CO Tap Water Safe? Quality & Contaminants

What was found in Westminster'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	2300 µg/L 57% of the EPA limit 4000 µg/L	2/3	SYR4
Nitrate	180 µg/L 1.8% of the EPA limit 10000 µg/L	2/3	SYR4
Nitrate-Nitrite	180 µg/L 1.8% of the EPA limit 10000 µg/L	2/3	SYR4
Nitrite	60 µg/L 6% of the EPA limit 1000 µg/L	1/3	SYR4
Barium	57 µg/L 2.9% of the EPA limit 2000 µg/L	2/3	SYR4
TTHM	49.76 µg/L 62% of the EPA limit 80 µg/L	2/3	SYR4
Xylenes, Total	32.5 µg/L 0.3% of the EPA limit 10000 µg/L	2/3	SYR4
Total Haloacetic Acids (HAA5)	24.1 µg/L 40% of the EPA limit 60 µg/L	2/3	SYR4
Chloroform	22.5 µg/L No EPA limit set	1/3	SYR4
Lithium	21.3 µg/L No EPA limit set	1/3	UCMR-5
Bromodichloromethane	18 µg/L No EPA limit set	2/3	SYR4
Dichloroacetic Acid	11.8 µg/L No EPA limit set	1/3	SYR4
Dibromochloromethane	9.54 µg/L No EPA limit set	2/3	SYR4
Monochloroacetic Acid	7.5 µg/L No EPA limit set	1/3	SYR4
Bromoform	6.4 µg/L No EPA limit set	2/3	SYR4
Trichloroacetic Acid	5.01 µg/L No EPA limit set	1/3	SYR4
Chromium	5 µg/L 5% of the EPA limit 100 µg/L	2/3	SYR4
Ethylbenzene	4.1 µg/L 0.6% of the EPA limit 700 µg/L	1/3	SYR4
Selenium	3.3 µg/L 6.6% of the EPA limit 50 µg/L	1/3	SYR4
Dibromoacetic Acid	2.5 µg/L No EPA limit set	2/3	SYR4
Gross Alpha, Excl. Radon And U	2.2 pCi/L 15% of the EPA limit 15 pCi/L	2/3	SYR4
Monobromoacetic Acid	1.3 µg/L No EPA limit set	1/3	SYR4
Combined Uranium	1.1 µg/L 3.7% of the EPA limit 30 µg/L	1/3	SYR4
Arsenic	0.8800 µg/L 8.8% of the EPA limit 10 µg/L	1/3	SYR4
Di(2-ethylhexyl) Phthalate	0.7000 µg/L 12% of the EPA limit 6 µg/L	1/3	SYR4
Cadmium	0.1300 µg/L 2.6% of the EPA limit 5 µg/L	1/3	SYR4
Lead	0.0013 mg/L 8.7% of the EPA limit 0.0150 mg/L	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 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 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 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.