Water Quality in Fort Collins, CO

Fort Collins's water quality is good overall. Hardness is low at 105 PPM, and no contaminants exceed health guidelines. Most homes here do not need a water softener.

Fort Collins Utilities · Source: Cache la Poudre River, Horsetooth Reservoir · Serves 169,810 residents

105
Hardness (PPM)
116
TDS (PPM)
0.6
Chlorine (mg/L)
4
PFAS (ppt)
2
Lead (ppb)
105 PPM 0 400 Moderately Hard
CONTAMINANT LEVELS Hardness 105 PPM TDS 116 PPM PFAS 4 ppt Lead 2 ppb Chlorine 0.6 mg/L Nitrate 1 mg/L

Hardness Scale: Where Fort Collins Falls

Soft 060120180250400+
Generally good quality

Fort Collins draws from the Poudre River and Horsetooth Reservoir. Mountain-sourced water is moderately soft to moderate in hardness.

What Fort Collins's Water Means for Your Home

Fort Collins's water is moderately hard at 105 PPM. At this level, hard water is not a significant concern for most households. Scale buildup is minimal, and a water softener would provide little measurable benefit. If you are considering water treatment in Fort Collins, focus on contaminant filtration rather than softening.

Beyond hardness, Fort Collins's water quality is generally within EPA guidelines for regulated contaminants. Chlorine is present at 0.6 mg/L as a disinfectant residual, which is normal for municipal water systems. If you notice a pool-like taste or experience dry skin, a whole-house carbon filter is the most common and affordable solution. For homeowners who want to understand the full picture, requesting your utility's annual Consumer Confidence Report provides neighborhood-level data.

ContaminantDetectedHealth GuidelineLegal LimitStatus
Hardness (as CaCO₃)105 PPM< 60 PPMNo federal limit✓ OK
Total Dissolved Solids116 PPM< 300 PPM500 PPM✓ OK
PFAS (total)4 ppt4 ppt (EPA)4 ppt (2024)✓ OK
Lead2 ppb0 ppb (no safe level)15 ppb (action level)✓ Low
Chlorine / Chloramine0.6 mg/LTaste threshold ~1.04.0 mg/L✓ Normal
Nitrate1 mg/L5 mg/L10 mg/L✓ OK

Recommendations for Fort Collins Homes

🔄 Salt-Free Conditioner (Optional)
At 105 PPM, Fort Collins's water is moderately hard. Scale buildup is slow but noticeable over years, especially in tankless water heaters. A salt-free conditioner is a low-maintenance option if you want to extend appliance life.
Learn more about this solution →

About Fort Collins's Water Supply

Water Utility: Fort Collins Utilities

Water Source: Cache la Poudre River, Horsetooth Reservoir

Population Served: 169,810

Hardness: 105 PPM (6.1 grains per gallon)

Water quality can vary by neighborhood and season. The values above represent typical averages reported by Fort Collins Utilities. To get exact numbers for your address, request a copy of the most recent Consumer Confidence Report (CCR) from your utility, or have your water independently tested.

Compare Fort Collins to Other Colorado Cities

Denver

90 PPM · Moderately Hard

Colorado Springs

101 PPM · Moderately Hard

Aurora

73 PPM · Moderately Hard

Lakewood

73 PPM · Moderately Hard

Thornton

78 PPM · Moderately Hard

Arvada

81 PPM · Moderately Hard

Frequently Asked Questions About Fort Collins Water

Is Fort Collins tap water safe to drink?
Fort Collins's water meets EPA legal standards for drinking water safety. However, legal limits and health-optimal levels are different things. Review the contaminant table above for specific numbers and how they compare to both legal limits and health guidelines.
Do I need a water softener in Fort Collins?
At 105 PPM, Fort Collins's water is moderately hard. Some homeowners at this level do not notice problems, while others see spotting on glassware, film on shower doors, or reduced soap lathering. Homes with tankless water heaters at this hardness level should strongly consider at least a salt-free conditioner, as scale buildup inside the heat exchanger can void the warranty. For other homes, it depends on your sensitivity and fixtures.
What water filter is best for Fort Collins?
The best filter depends on which contaminants you want to address. See our softener vs. filter guide to understand the difference between these categories.
Where does Fort Collins's water come from?
Fort Collins's drinking water is sourced from Cache la Poudre River, Horsetooth Reservoir and treated by Fort Collins Utilities. Fort Collins draws from the Poudre River and Horsetooth Reservoir. Mountain-sourced water is moderately soft to moderate in hardness.
What is the hardness of Fort Collins water in grains per gallon?
Fort Collins's water hardness is 6.1 grains per gallon (GPG), which equals 105 parts per million (PPM). This is classified as moderately hard. To convert: 1 GPG = 17.1 PPM.
Does Fort Collins water damage tankless water heaters?
At 6.1 GPG, Fort Collins's water is unlikely to cause significant issues for tankless water heaters. However, if you notice reduced flow or efficiency over time, scale buildup could be a factor. Annual flushing with vinegar is good maintenance regardless of hardness.
Is Fort Collins water safe for babies and infants?
Fort Collins's water meets all EPA safety standards and is generally considered safe for preparing infant formula. The hardness minerals (calcium and magnesium) are not harmful. If your home has older plumbing, running cold water for 30 seconds before use is a good precaution to flush any lead from pipes.

Data sources. Water quality data compiled from EPA SDWIS, EWG Tap Water Database, USGS water hardness studies, and the Fort Collins Utilities Consumer Confidence Report. Hardness and contaminant levels represent typical average values and may vary by neighborhood and season. Last updated: 2026-02-12.