Water Quality in Hamilton, OH

Hamilton's water has hard water (128 PPM). Read below for a full breakdown.

City of Hamilton Water · Source: Great Miami River wells · Serves 63,992 residents

128
Hardness (PPM)
236
TDS (PPM)
1.1
Chlorine (mg/L)
4
PFAS (ppt)
4
Lead (ppb)
128 PPM 0 400 Hard
CONTAMINANT LEVELS Hardness 128 PPM TDS 236 PPM PFAS 4 ppt Lead 4 ppb Chlorine 1.1 mg/L Nitrate 2 mg/L

Hardness Scale: Where Hamilton Falls

Soft 060120180250400+
Hard water

Hamilton's Great Miami Buried Valley Aquifer wells produce hard water from glacial limestone deposits.

What Hamilton's Water Means for Your Home

Hamilton's water is hard at 128 PPM. This level of hardness causes gradual scale accumulation on plumbing fixtures, inside water heaters, and on dishware. While not as aggressive as cities in the 200+ PPM range, homeowners who install a water softener or salt-free conditioner typically notice improved soap lathering, cleaner dishes, and longer appliance lifespans.

Beyond hardness, Hamilton's water quality is generally within EPA guidelines for regulated contaminants. Chlorine is present at 1.1 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)128 PPM< 60 PPMNo federal limit⚠ Hard
Total Dissolved Solids236 PPM< 300 PPM500 PPM✓ OK
PFAS (total)4 ppt4 ppt (EPA)4 ppt (2024)✓ OK
Lead4 ppb0 ppb (no safe level)15 ppb (action level)✓ Low
Chlorine / Chloramine1.1 mg/LTaste threshold ~1.04.0 mg/L✓ Normal
Nitrate2 mg/L5 mg/L10 mg/L✓ OK

Recommendations for Hamilton Homes

💧 Water Softener or Conditioner
At 128 PPM, Hamilton's water is hard. You will see gradual scale buildup on fixtures and inside water heaters. A salt-based softener removes hardness completely, while a salt-free conditioner prevents scale without removing the minerals. Your choice depends on whether you want soft-feeling water or just scale prevention.
Learn more about this solution →

About Hamilton's Water Supply

Water Utility: City of Hamilton Water

Water Source: Great Miami River wells

Population Served: 63,992

Hardness: 128 PPM (7.5 grains per gallon)

Water quality can vary by neighborhood and season. The values above represent typical averages reported by City of Hamilton Water. 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 Hamilton to Other Ohio Cities

Columbus

180 PPM · Hard

Cleveland

136 PPM · Hard

Cincinnati

123 PPM · Hard

Toledo

148 PPM · Hard

Akron

135 PPM · Hard

Dayton

267 PPM · Extremely Hard

Frequently Asked Questions About Hamilton Water

Is Hamilton tap water safe to drink?
Hamilton'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 Hamilton?
It is worth considering. At 128 PPM, Hamilton's water is hard. You will notice gradual scale buildup in pipes and on fixtures over time. A salt-based softener extends appliance life and improves soap efficiency. A salt-free conditioner is a lower-maintenance alternative if you primarily want to prevent scale.
What water filter is best for Hamilton?
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 Hamilton's water come from?
Hamilton's drinking water is sourced from Great Miami River wells and treated by City of Hamilton Water. Hamilton's Great Miami Buried Valley Aquifer wells produce hard water from glacial limestone deposits..
What is the hardness of Hamilton water in grains per gallon?
Hamilton's water hardness is 7.5 grains per gallon (GPG), which equals 128 parts per million (PPM). This is classified as hard. To convert: 1 GPG = 17.1 PPM.
Does Hamilton water damage tankless water heaters?
Yes. Most tankless water heater manufacturers recommend water hardness below 7 to 11 GPG (120 to 188 PPM). At 7.5 GPG, Hamilton's water exceeds this threshold. Scale buildup inside the heat exchanger reduces efficiency and can void the manufacturer's warranty. A water softener installed upstream of the tankless heater is the standard solution.
Is Hamilton water safe for babies and infants?
Hamilton'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.
How much does hard water cost a Hamilton household per year?
At 128 PPM, hard water costs the average Hamilton household an estimated $800 to $1,200 per year in hidden costs. This includes 15 to 25 percent higher water heating bills from scale insulation, 50 to 75 percent more soap and detergent usage, shorter appliance lifespans (water heaters, dishwashers, washing machines), and increased plumbing maintenance. A water softener typically costs $600 to $1,500 installed and $50 to $100 per year in salt, which means most Hamilton households see a return on investment within 1 to 2 years.

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