What It Is
Water hardness is a measure of dissolved calcium and magnesium content in water, expressed in grains per gallon (GPG) or milligrams per liter (mg/L). Soft water measures below 1 GPG; hard water is generally considered 7 GPG and above. Hard water is safe to drink but causes scale buildup in water heaters and appliances, reduces soap effectiveness, and leaves mineral deposits on fixtures and glassware. Northeast Ohio groundwater is commonly in the moderately hard to very hard range.
What It Does
Calcium and magnesium are naturally occurring minerals that dissolve into groundwater as it passes through limestone and other rock formations. The resulting hardness is harmless from a health standpoint, but it creates measurable problems in the home over time. When hard water is heated - in a water heater, dishwasher, or coffee maker - the dissolved minerals precipitate out of solution and form scale deposits. Scale is a poor conductor of heat, so it insulates heating surfaces, forcing appliances to work harder and use more energy to achieve the same output.
Hard water also interferes with soap chemistry. Soap forms suds by reacting with water, but calcium and magnesium ions compete with the soap molecules, forming insoluble soap scum instead of lather. This is why hard water requires more soap or detergent to achieve the same cleaning result, and why hard water leaves a film on skin, dishes, and shower surfaces.
How It Works
Water hardness is tested by measuring the concentration of calcium and magnesium ions. The most common unit in the US plumbing industry is grains per gallon (GPG), where 1 grain equals approximately 17.1 mg/L. A general scale: 0-1 GPG is soft, 1-7 GPG is moderately hard, 7-10 GPG is hard, and above 10 GPG is very hard. Municipal water utilities publish annual water quality reports that include hardness levels. Private well water hardness varies by location and aquifer geology - a water test from a certified lab provides accurate measurement.
Common Problems or Signs of Failure
- White or gray crusty deposits around faucets, showerheads, and drain edges - calcium carbonate scale
- Water heater rumbling or popping noises - sediment and scale buildup on heating elements or tank floor
- Cloudy glasses and dishes coming out of the dishwasher
- Soap does not lather well; skin feels filmy after washing
- Reduced flow from showerheads - mineral buildup clogging the spray holes
- Premature water heater failure - scale reduces efficiency and accelerates corrosion
Can a Homeowner Check It?
- Purchase an inexpensive water hardness test strip from a hardware or pool supply store - dip in water and compare to the color chart
- Check for scale buildup on showerheads and faucet aerators - white crusty deposits indicate hard water
- Contact your municipal water utility for their annual water quality report, which includes hardness data
- If on a private well, have a certified water test done to get accurate hardness and other mineral readings
When to Call a Plumber
If your water hardness is high enough to be causing scale-related problems - premature water heater wear, clogged fixtures, or noticeable soap scum buildup - a plumber can evaluate your options and install a water softener sized for your household usage and hardness level. Softener installation is a plumbing job that involves tapping into the main supply line and adding a drain connection for the regeneration cycle.
Related Plumbing Problems
Related Plumbing Terms
Related Gray's Services
Have a Plumbing Question? We Can Help.
Gray's Precision Plumbing serves Northeast Ohio. Call or text for a straight answer on what's wrong and how to fix it.
Call 440-723-8850 Send a Message