Water Hardness in Colorado (CO)

Colorado has an average water hardness of 170 ppm (9.9 grains per gallon), which is classified as Moderately Hard . Water hardness at this level may cause noticeable scale buildup on fixtures and reduced soap lathering. Some Colorado households choose to install a water softener or conditioner for improved water quality, though it is not strictly necessary. Water hardness varies between cities — from 55 ppm in Boulder to 280 ppm in Grand Junction.

State Average 170 ppm 9.9 gpg
Hardness Level Moderately Hard No softener needed
Hardest City Grand Junction 280 ppm
Softest City Boulder 55 ppm

Water Hardness by City in Colorado

The table below shows water hardness data for 9 cities in Colorado, sorted from hardest to softest. Click any city name for detailed information including water source, treatment recommendations, and estimated hard water costs.

City Hardness (PPM) Grains/Gallon Level Water Source pH TDS Utility
Grand Junction 280 ppm 16.4 gpg Very Hard Surface 8 450 City of Grand Junction
Pueblo 240 ppm 14 gpg Hard Mixed 7.9 380 Pueblo Board of Water Works
Fort Collins 200 ppm 11.7 gpg Hard Mixed 7.8 300 Fort Collins Utilities
Loveland 170 ppm 9.9 gpg Moderately Hard Mixed 7.6 265 City of Loveland Water and Power
Durango 130 ppm 7.6 gpg Moderately Hard Surface 7.5 200 City of Durango Utilities
Aurora 105 ppm 6.1 gpg Slightly Hard Mixed 7.5 155 Aurora Water
Denver 90 ppm 5.3 gpg Slightly Hard Surface 7.3 130 Denver Water
Colorado Springs 80 ppm 4.7 gpg Slightly Hard Surface 7.2 115 Colorado Springs Utilities
Boulder 55 ppm 3.2 gpg Soft Surface 7.1 82 City of Boulder Utilities
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Understanding Water Hardness in Colorado

Water Sources in Colorado

The majority of cities in Colorado draw their water from surface sources such as rivers, lakes, and reservoirs. Surface water generally contains fewer dissolved minerals than groundwater, which helps explain the overall hardness profile of the state. Cities that rely on surface water tend to have softer water because the water has less contact time with mineral-bearing rock formations underground.

Hardness Variation Across Colorado

Water hardness in Colorado ranges from 55 ppm in Boulder to 280 ppm in Grand Junction — a difference of 225 ppm. This variation means that treatment recommendations differ significantly between cities. Residents of Grand Junction and other cities with hard water should seriously consider installing a water softener to protect their homes. At 280 ppm, the annual cost of hard water damage to appliances, plumbing, and increased cleaning product usage can easily exceed $12. Meanwhile, Boulder enjoys naturally soft water that needs no treatment at all — an advantage that saves residents money on both equipment and ongoing maintenance.

Recommended Treatment for Colorado Water

Based on the average water hardness of 170 ppm in Colorado, a water softener is not strictly necessary, but some homeowners may prefer treated water. The most effective treatment options for Colorado's water hardness level include:

How Colorado Compares to Other States

Below is a comparison of Colorado with five states that have similar average water hardness levels. Understanding how your state compares can help you gauge whether your water is typical for the region or unusually hard or soft.

State Avg Hardness Level Cities
Colorado (CO) 170 ppm Moderately Hard 9
Idaho (ID) 170 ppm Moderately Hard 8
Oklahoma (OK) 170 ppm Moderately Hard 8
Missouri (MO) 160 ppm Moderately Hard 8
Montana (MT) 180 ppm Moderately Hard 8
Ohio (OH) 160 ppm Moderately Hard 9

Find Your City's Water Hardness

Use our water hardness lookup tool to find your specific city in Colorado, or browse all 50 states to compare water hardness across the country. If your water is hard, visit our treatment solutions guide to find the right softener or conditioner for your home.