Water Hardness in Denver, CO
Colorado · 24 zip codes · 30 matched water systems
City avg (weighted): 90 PPM
Dataset updated March 9, 202630 matched water systems in the city rollupIndividual systems and ZIPs can differ. Methodology
Is Denver, CO Water Hard or Soft?
The displayed hardness for Denver, CO is 90 PPM (5.3 GPG) from Denver Water Board, classified as slightly hard. The citywide weighted average is 90 PPM.
Water hardness is not a drinking-water safety score. It measures calcium and magnesium minerals, and address-level results can shift by pressure zone, supply blend, building plumbing, or private well.
How this city reading is built
This city reading is a weighted rollup across 30 matched water systems and 24 ZIP codes. Citywide readings are useful for comparison, but individual utility zones and ZIPs can differ.
Hardness is a mineral-content reading, not a drinking-water safety rating. Use it for scale, appliance, and softener decisions; check your utility report or test your tap before sizing treatment equipment. See how we calculate local readings.
Water Systems in Denver
These systems are matched to Denver, CO. Citywide readings are useful for comparison, but the system serving a specific address may differ from the city average.
| Water System | Source | Hardness | Pop. Served |
|---|---|---|---|
| Denver Water Board CO0116001 | surface water | 90 PPM Slightly HardUSGS estimate: 156 PPM | |
| Arvada City Of CO0130001 | surface water | 90 PPM Slightly HardUSGS estimate: 156 PPM | |
| Consolidated Mutual Maple Grove CO0130020 | surface water | 90 PPM Slightly HardUSGS estimate: 156 PPM | |
| Green Mountain Wsd CO0130321 | surface water | 90 PPM Slightly HardUSGS estimate: 108 PPM | |
| Bancroft Clover Wsd CO0130133 | surface water | 90 PPM Slightly HardUSGS estimate: 156 PPM |
Zip Codes in Denver, CO
What This Means For You
Use this city reading as a local planning estimate, not a final treatment specification. Hardness can vary by utility zone, seasonal blend, private well, and building plumbing. Confirm your tap reading with a utility report or home hardness test before sizing equipment.
Know your water hardness?
If you've tested your water or have your utility's CCR report, share your reading to help us improve accuracy for Denver, CO.
Frequently Asked Questions
How hard is the water in Denver, CO?
The citywide weighted average water hardness in Denver, CO is 90 PPM (5.3 GPG), classified as slightly hard. This is based on 30 matched water systems.
Do I need a water softener in Denver, CO?
At 90 PPM, the citywide average is relatively soft. A water softener is generally not necessary.
Is hard water in Denver, CO safe to drink?
Water hardness itself is a mineral-content reading, not a drinking-water safety rating. Calcium and magnesium are naturally occurring minerals, but you should check your utility's Consumer Confidence Report for contaminant and compliance information.
How many water systems serve Denver, CO?
Denver, Colorado is served by 30 matched water systems across 24 zip codes.
Learn More About Your Water
How to Test Water Hardness at Home
Compare free lookups, soap tests, test strips, liquid drop kits, and lab tests for measuring water hardness.
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