Drinking Water Protection
- Drinking Water Protection Home
- About Us
- A-Z Index of Contaminants in Water
- Community Public Water Supply
- Drinking Water Institute
- Drinking Water Revolving Fund
- Noncommunity Public Water Supply
- Source Water Protection
- Water Operator and Certification Training
- DWP Contacts
- Annual Reports
- Drinking Water Risk Communication Toolkit
- Fact Sheets
- Invisible Heroes Videos: Minnesota's Drinking Water Providers
- Noncom Notes Newsletter
- Sample Collection Procedures (videos, pictures, written instructions)
- Waterline Newsletter
- 10 States Standards
- Clean Water Fund
- Health Risk Assessment – Guidance Values and Standards for Water
- Minnesota Well Index
- Water and Health
- Wells and Borings
Environmental Health Division
Home Water Softening
Frequently Asked Questions
Download a print version of this page:
Home Water Softening: Frequently Asked Questions (PDF)
What is soft water?
Water naturally has a variety of minerals such as calcium and magnesium. Whether a water supply is considered “hard” or “soft” depends on how much of these minerals are in your water. Soft water contains lower levels of calcium and/or magnesium than hard water.
Do I need to soften my water?
There is no requirement to soften your water. The decision to soften is a personal choice that can affect your home and the environment. If your water’s hardness is greater than 7 grains per gallon or 120 mg/L, then you might need a water softener to ensure your appliances run well and to improve the taste, smell, or look of your water.
Understand the hardness of your water
To decide if you need a home water softener, learn about the hardness of your home’s water. You can measure the hardness of your water using a test kit or an independent laboratory. Search for labs at Environmental Laboratory Accreditation Program. If you get your water from a community water system, you can contact them directly for information about your water’s hardness.
Advantages of home water softening
- Prevents build-up of minerals (scale) on the inside of pipes, fixtures, and hot water heaters.
- Lengthens the life of some appliances.
- Reduces or prevents mineral spots on glassware.
- Prevents or reduces soap films and detergent curds in sinks, bathtubs, and washing machines.
Disadvantages of home water softening
- Can corrode your pipes. The corroded metal from the pipes can end up in your water. This can contribute to elevated lead and copper levels in drinking water.
- Potential health effects from additional sodium.
- Regular testing of the water and maintenance of the softener is necessary to make sure the softener is working properly.
- Negative impacts to the environment from salt use.
- The water used to regenerate the softener beads ends up as waste.
How do home softeners work?
Home water softeners, also called ion exchange units, are appliances that remove calcium, magnesium, and other minerals from drinking water. Resin beads inside the softener trap the calcium and magnesium and exchange them for sodium or potassium. Once the resin beads become full of calcium and magnesium, a highly-concentrated salt or potassium solution removes the calcium and magnesium from the beads. After passing through the beads, the resulting chloride solution becomes a waste stream that goes down the drain and ultimately into the environment.
If I have a home softener, how do I use it correctly?
Make sure you have your softener installed and maintained according to the manufacturer’s instructions. Read the manufacturer’s instructions before adding any chemicals to the unit. Maintaining your softener will keep your water quality stable. This will help prevent issues with corrosion. In addition:
- If you get your water from a community water system, check to see if your community already softens the water. Soft water provided by a utility does not need additional softening and may cause corrosion issues for your home.
- Make sure the softener is set to the hardness of your water supply. If the hardness is set too high, the softener will cost more to operate and waste water, costing you extra money.
- If your home has new copper plumbing, do not run the water softener for at least the first few weeks you use water at your house. This will help the plumbing form a protective mineral layer to reduce the risk of consuming excess copper. Learn more about Copper in Drinking Water.
- Make sure that the softener is filled with sodium or potassium chloride following the manufacturer’s recommendations.
- Soften only what you need to. People often choose to soften showers, sinks, and laundry hookups. Toilets, hose bibs, basement sinks, and other cold water taps typically do not need to be connected to a softener. In many cases, people choose to soften only the hot water.
- Depending on your water quality, some softeners may be able to fully or partially remove copper, iron, manganese, and radium, in addition to calcium and magnesium. Note that copper can reenter the water after if leaves the softener and passes through your home’s pipes and plumbing. These softeners may have special filter media and may cost more than typical softeners. Before using a softener for this purpose, follow the recommendations listed at Home Water Treatment.
Check your manufacturer’s instructions for dealing with these issues:
- Clogging: If your water supply is cloudy, it may clog the resin in the softener with mud and clay. Backwashing will typically solve this problem. Adding a sediment filter before the softener could also help.
- Iron or manganese fouling: Iron or manganese that has been exposed to air or chlorine can clog the resin and prevent it from working. This is known as fouling. Sometimes it may be necessary to filter the water before it gets to your softener to prevent fouling. Commercial cleaners are available if the resin becomes fouled. Cleaners need to be used according to manufacturer instructions to avoid contamination.
- Bacteria and fungi: If your water supply is not disinfected prior to softening, bacteria and fungi can potentially grow on the surface. This can reduce the effectiveness of your softener.
What are the health effects of home softening?
A water softener that uses sodium chloride (salt) increases the amount of sodium in the water you drink at home. Consider the following if you have a home softener:
- If you or someone in your home has a history of high blood pressure, consult a doctor about drinking softened water.
- You can decrease the amount of sodium you drink:
- Have an un-softened tap for cooking and drinking.
- Regenerate your softener with potassium chloride instead of sodium chloride (salt). Potassium chloride is available at most stores that sell softener salt.
The calcium, iron, and magnesium removed by softening are not harmful and may be beneficial sources of essential elements needed by the body. Removing them from your water may mean you will have to get more of them from your diet.
What are the environmental impacts of home softening?
Minnesota has a growing problem with chloride in water. Chloride in water threatens our fresh-water fish and other aquatic life. The chloride used in home water softeners can also affect the water used for drinking. It takes only one teaspoon of sodium chloride salt to permanently pollute five gallons of water. Once salt is in water, there is no easy way to remove it.
In some communities, home water softeners drain to municipal wastewater treatment plants, which are not designed to remove chloride. The chloride passes through the treatment plant and ends up in our lakes and streams. In homes with private wells and home softeners, chloride drains to the home’s septic system and then ends up in lakes and streams.