Tap Water Quality Report

Tap water quality in WESTMINSTER, Colorado

Served by WESTMINSTER CITY OF. 202,078 residents.

Average score 67/100
Utilities 1
Population 202,078
D
67/100
Below Average
ⓘ How did we get this rating?
Quick answer

Tap water in WESTMINSTER, Colorado receives a grade of D (67/100) from TapWaterSafety.org. It's served by WESTMINSTER CITY OF. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Bromodichloromethane significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?

What's in WESTMINSTER's tap water

Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving WESTMINSTER.

Haloacetic acids (HAA9) significantly above health guideline

Moderate concern

Haloacetic acids (HAA9) detected at 19.6 ppb, 327x above the EWG health guideline of 0.06 ppb.

Total trihalomethanes (TTHMs) significantly above health guideline

Moderate concern

Total trihalomethanes (TTHMs) detected at 32.8 ppb, 219x above the EWG health guideline of 0.15 ppb.

Bromodichloromethane significantly above health guideline

Moderate concern

Bromodichloromethane detected at 11.9 ppb, 198x above the EWG health guideline of 0.06 ppb.

Recommended filters for WESTMINSTER

Filters matched to the specific contaminants in WESTMINSTER's water supply.

Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.

All contaminants detected in WESTMINSTER's tap water

Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →

Contaminant Detected EWG
US health-based
EPA
US legal
EU DWD
Europe
WHO
global
CA PHG
strictest US
Tested
sample year
Status
Haloacetic acids (HAA9)
Disinfection byproduct
19.6 ppb 0.06 327× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
32.8 ppb 0.15 80.0 100 219× over
Bromodichloromethane
Disinfection byproduct
11.9 ppb 0.06 198× over
Haloacetic acids (HAA5)
Disinfection byproduct
9.73 ppb 0.1 60.0 60 97× over
Dibromochloromethane
Disinfection byproduct
8.76 ppb 0.1 88× over
Dibromoacetic acid
Disinfection byproduct
1.48 ppb 0.03 49× over
Chloroform
Disinfection byproduct
11.0 ppb 0.4 28× over
Trichloroacetic acid
Disinfection byproduct
2.79 ppb 0.1 28× over
Dichloroacetic acid
Disinfection byproduct
5.44 ppb 0.2 27× over
Chromium (hexavalent)
Heavy metal
0.178 ppb 0.02 8.9× over
Radium, combined (-226 and -228)
Radiological
0.29 pCi/L 0.05 5.0 5.8× over
Bromoform
Disinfection byproduct
1.16 ppb 0.5 2.3× over
Uranium
Radiological
0.39 pCi/L 0.43 20.0 30 30 0.43 Below guideline
Chlorate
Disinfection byproduct
176.7 ppb 210.0 Below guideline
Molybdenum
Other
3.06 ppb 40.0 Below guideline
Barium
Heavy metal
46.3 ppb 700.0 2000.0 1300 2000 Below guideline
Manganese
Heavy metal
0.499 ppb 100.0 50 80 Below guideline
Vanadium
Other
0.015 ppb 21.0 Below guideline
Monochloroacetic acid
Disinfection byproduct
0.0219 ppb 53.0 Below guideline
Strontium
Radiological
0.191 ppb 1500.0 Below guideline
Chromium (total)
Heavy metal
0.347 ppb 100.0 Below guideline
Fluoride
Inorganic
0.577 ppm 4.0 1.5 1.5 Below guideline
Lithium
Other
20.4 ppb Below guideline

All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.

Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.

Treatment plant contact info

For service issues, water quality concerns, or to request a Consumer Confidence Report from WESTMINSTER CITY OF.

Treatment Plant

FacilityNORTHWEST WATER TREATMENT PLANT

ZIP codes served

WESTMINSTER's public water systems serve the following ZIP codes: