Water Quality Report · Updated May 12, 2026
DENVER WATER BOARD
DENVER WATER BOARD delivers tap water graded C (67/100) by TapWaterSafety.org. The utility serves approximately 1,287,000 residents in DENVER, Colorado using surface water. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline. For questions, the utility can be reached at 303-994-6605.
Is DENVER tap water safe to drink?
DENVER WATER BOARD delivers tap water that earns a grade of C (67/100) from TapWaterSafety.org — an average rating, with several contaminants above health guidelines but generally compliant with US legal limits.
The utility serves 1,287,000 residents in DENVER, drawing from surface water.
Public testing data identifies 11 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Haloacetic acids (HAA5), Bromodichloromethane, Trichloroacetic acid, Dichloroacetic acid, Chloroform, Dibromochloromethane, Radium, combined (-226 and -228), Dibromoacetic acid, Chromium (hexavalent). For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.
Quick actions for DENVER residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for DENVER WATER BOARD.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 14.7 ppb, 246x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 28.9 ppb, 192x above the EWG health guideline of 0.15 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 16.6 ppb, 166x above the EWG health guideline of 0.1 ppb.
Contact DENVER WATER BOARD
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Treatment Plant
Recommended water filters for DENVER
Filters matched to the specific contaminants in this water supply.
Carbon block (NSF/ANSI 42 + 53)
$40-$750Activated carbon is highly effective for disinfection byproducts like TTHM and HAA5.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
Score breakdown
This utility's overall score of 67/100 breaks down across five weighted components. Read the full methodology →
Contaminants detected — international standards comparison
Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). 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 |
14.7 ppb | 0.06 | — | — | — | — | — | 246× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
28.9 ppb | 0.15 | 80.0 | 100 | — | — | — | 192× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
16.6 ppb | 0.1 | 60.0 | 60 | — | — | — | 166× over |
| Bromodichloromethane Disinfection byproduct |
8.02 ppb | 0.06 | — | — | — | — | — | 134× over |
| Trichloroacetic acid Disinfection byproduct |
6.33 ppb | 0.1 | — | — | — | — | — | 63× over |
| Dichloroacetic acid Disinfection byproduct |
10.1 ppb | 0.2 | — | — | — | — | — | 51× over |
| Chloroform Disinfection byproduct |
18.9 ppb | 0.4 | — | — | — | — | — | 47× over |
| Dibromochloromethane Disinfection byproduct |
1.9 ppb | 0.1 | — | — | — | — | — | 19× over |
| Radium, combined (-226 and -228) Radiological |
0.74 pCi/L | 0.05 | 5.0 | — | — | — | — | 15× over |
| Dibromoacetic acid Disinfection byproduct |
0.119 ppb | 0.03 | — | — | — | — | — | 4.0× over |
| Chromium (hexavalent) Heavy metal |
0.0378 ppb | 0.02 | — | — | — | — | — | 1.9× over |
| Nitrate Inorganic |
0.0578 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | Below guideline |
| Nitrate and nitrite Inorganic |
0.0578 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | Below guideline |
| Molybdenum Other |
6.86 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
8.41 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Barium Heavy metal |
34.0 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Uranium Radiological |
0.02 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | Below guideline |
| Cadmium Heavy metal |
0.00122 ppb | 0.04 | 5.0 | 5 | 3 | 0.04 | — | Below guideline |
| Vanadium Other |
0.264 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Bromoform Disinfection byproduct |
0.00622 ppb | 0.5 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.171 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| 4-Androstene-3,17-dione Other |
0.027 ppt | — | — | — | — | — | — | Below guideline |
| Chlorodifluoromethane Other |
0.00808 ppb | — | — | — | — | — | — | Below guideline |
| Chromium (total) Heavy metal |
0.0841 ppb | — | 100.0 | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.607 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Lithium Other |
4.08 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 (4th ed.), California OEHHA PHGs, EWG Tap Water Database.
DENVER WATER BOARD service area
This water system serves 1 community in Denver County, Colorado. Click any city for its dedicated tap water quality page.
Find the right filter for DENVER water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.