Hard water contains high levels of calcium and magnesium. It leaves white scale on fixtures, spots on dishes, and buildup inside water heaters and pipes. Water above about 120 mg/L (around 7 grains per gallon) is generally considered hard. A water softener is the most effective fix, and a simple test confirms how hard your water is.
Reviewed by Ron Olsen, Master Plumber, certified in Washington
Why Some Cities Have Hard Water
- Local geology
- Groundwater passing through limestone and chalk picks up dissolved minerals.
- Water source
- Well water and some municipal supplies are naturally harder.
How to Check and Manage It
- Check your water utility's annual water quality report for its hardness level.
- Use a hardness test strip kit for a quick reading.
- Soak shower heads and aerators in vinegar to dissolve scale.
- Flush your water heater more often if you have hard water.
When to Call a Plumber
Call a plumber to test your water and install a softener or treatment system, especially if scale is clogging fixtures, your water heater is noisy, or appliances are wearing out early.
The repair is usually part of water softeners & filtration, which explains what the plumber does and what affects the cost.
Water Hardness by City
What our city pages say about water hardness:
- Eagan, MN: Very hard, 18 to 20 grains per gallon (310 to 345 ppm).
- St. Joseph, MO: Very hard, about 222 ppm (about 13 grains per gallon).
- Peoria, IL: Extremely hard, 19 to 37 grains per gallon (300 to 600 mg/L).
- Indianapolis, IN: Very hard, averaging about 317 ppm (19 grains per gallon), with a system range of 8.7 to 27 grains per gallon.
- Kansas City, KS: Very hard, about 17.5 grains per gallon (300 ppm).
- Chandler, AZ: Very hard, averaging 16.5 grains per gallon, with a range of 5 to 20.
- Enterprise, NV: Very hard; the Las Vegas Valley Water District reports about 16 to 17 grains per gallon (280 to 291 ppm).
- Deltona, FL: Very hard, 12 to 17 grains per gallon depending on the well.
Hard Water Questions
Is hard water safe to drink?
Hard water is generally safe to drink. Its problems are scale, appliance wear and how it feels on skin and hair.
Does hard water damage water heaters?
Yes. Scale builds up in the tank and on heating elements, reducing efficiency and shortening the heater's life.