Are Water Softeners Bad For Copper Pipes?

Is Softened water more corrosive? This is a misconception that many have. In fact, water softeners prevent copper pipe corrosion as it transforms your home's hard water into soft water.

So what is “hard water” and why does it corrode your copper pipes?

Hard water is water with a high concentration of dissolved minerals like calcium, magnesium and other metals. Over time, these metals can wear out the inner lining of copper pipes, eventually creating pinhole leaks.

Hard water contains high amounts of minerals such as magnesium and calcium. Water hardness is measured in grains, and water with more than 1 grain per gallon is usually considered hard. Using a water softener will reduce the concentration of minerals in household water, making it soft. Generally, soft water is helpful to the operation of a home plumbing system. There are some precautions you may have to take, however, and in some cases soft water can harm portions of the plumbing system.

The minerals of calcium and magnesium carbonates tend to attach and stick to the surfaces of pipes and water heats, resulting in scale buildup, which restricts water flow in pipes. Steel piping is most susceptible to mineral buildup, while copper and plastic piping are less so. When minerals collect in pipes, the inside diameter is reduced, thus restricting water-flow volume. The resulting turbulence in the water can be abrasive and cause the walls of metal pipes walls to wear thin and spring leaks. Minerals also collect on plumbing fixtures such as faucets, showers and toilets. A water softener can help to reduce and even eliminate mineral buildup.

Luckily, a whole-home water softener removes dissolved minerals from your home’s water so that these metals don’t buildup or react negatively with your pipes. To reduce your risk for pitted corrosion, you’ll need to hire a water specialist to provide a soft water treatment system for your home.

What does softened water do to copper pipes?

Water softeners soften the water by removing minerals such as calcium and magnesium and replacing them with a softer mineral – sodium or potassium. Soft water can also make your hair and skin look and feel healthier because hard water can dry them out. This type of water can lather with soap, cleaning scum and dirt off easier than hard water. Household cleaning is performed more efficiently, leaving clothes and hair softer and cleaner. Thus, little detergent or soap is used, saving you money and prolonging the life of your dishwasher and washing machine.

This article aims to address the common misperception that cation-exchange water softening causes corrosion. This is not the case: a properly configured water softener does not make the treated water more corrosive. Here are a few confusing facts that often lead people to this erroneous conclusion. First, naturally soft water is typically corrosive. Therefore, softened water must also be corrosive, right? This is a fallacy because naturally soft water tends to be corrosive due to low pH and low TDS, while cation-exchange softening causes neither of these conditions.

How does this impact our pipes? This type of water can affect how long your metal pipes will last and how fast the pipes will corrode. Water that is soft will not create mineral build up within the pipes but it can create pinhole leaks as soft water is lacking in minerals making it aggressive towards unlined metal (copper) pipes. The reason is as this type of water is lacking minerals, it will pull minerals such as copper as it travels through the pipe systems. Eventually, the corrosion will perforate the pipe walls, creating pinhole leaks.

How does corrosion happen?

Copper is a metal that occurs naturally and is used to make many products, including parts for plumbing systems. Copper can get into your drinking water as the water passes through your household plumbing system. Your body needs some copper to stay healthy, but too much is harmful.

Corrosion is a natural process in which a material is degraded by the environment, sometimes to a more stable chemical state through oxidation or reduction reactions. This is a big problem in water distribution systems where metal pipes are continuously being corroded. Corrosion can cause many undesirable effects in plumbing. The physical effects of corrosion include leaks, color in the water and on surfaces, sediment and particulate in the water, taste and odor issues, and physical failure of the pipes.²

Copper can get into your drinking water as it passes through your plumbing system. Over time, plumbing parts with copper in them usually build up a natural coating that prevents copper from being dissolved into the water. Plumbing systems with copper parts fewer than three years old usually have not had time to build up this protective coating. You can take the steps below to help keep your drinking water safe:

• Let the water run for at least 30-60 seconds before using it for drinking or cooking if the water has not been turned on in over six hours.
• Use cold water for drinking, making food, and making baby formula. Hot water releases more copper from pipes than cold water.
• Test your water. In most cases, letting the water run and using cold water for drinking and cooking should keep copper levels low in your drinking water. If you are still concerned about copper, arrange with a laboratory to test your tap water. 

Drinking water with more than 1,300 micrograms of copper per liter of water (µg/L)* can be a health risk for everyone. If tests show you have levels of copper over 1,300 µg/L in your tap water after you let the water run 30-60 seconds, you may want to consider treating your water.

Eating or drinking too much copper can cause vomiting, diarrhea, stomach cramps, nausea, liver damage, and kidney disease. People with Wilson’s disease and some infants (babies under one year old) are extra sensitive to copper. Their bodies are not able to get rid of extra copper easily.

Learn More

Before hiring a water conditioning or softening company, make sure you research the company and know whether or not they offer a money-back guarantee if you’re not satisfied with the results.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. Be sure to work with a reputable company that offers a money-back guarantee and whose installers are certified by the Water Quality Association.