Learn More: Hard Water

Learn More: Hard Water

What is Hard Water?

Hard water is water containing high levels of dissolved minerals. Common hard water minerals are calcium (Ca) and magnesium (Mg). Metals including iron, aluminum, and manganese may also be present in hard water. The higher the mineral content the harder the water. Water hardness is usually defined as total hardness (TH) and primarily corresponds to the amount of calcium (Ca) and magnesium (Mg) salts measured in water.
Hard water is a common issue effecting more than 85% of the United States. Hard water in the home can dry out skin, leave deposits on fixtures and glassware, clog pipes and other appliances. If left untreated, scale can build up and create serious issues in the home. It is best to test for hard water and then find a treatment to resolve the issue.

Where does hardness come from?

Geographic areas that contain large amounts of limestone are particularly susceptible to hard water. Limestone is sedimentary rock characterized by high concentrations of calcium in the form of calcium carbonate (CaCO3): a mix of calcium ion (Ca++) and the carbonate (CO3-). As water travels through sedimentary rock and soil in the environment, it dissolves small amounts of minerals and carries them into our groundwater supply. The richer the water is in calcium (limestone) and magnesium the harder it is. Water that is deficient in limestone is classified as soft.

What is Scale?

Scale is a hard, thick coating of calcium carbonate observed on heating elements, plumbing fixtures, and water appliances. A common sign of hard water is the build-up of scale deposits. When carbon dioxide from the atmosphere reacts with water it exists mostly as a bicarbonate ion.
Extensive limestone deposits are the result of skeletonized microscopic marine organisms. Groundwaters dissolve the limestone acquiring calcium and bicarbonate ions and becoming “hard.” If the concentration of the calcium and bicarbonate ions is large enough “lime scale” will precipitate out on to surfaces such as your faucet in the form of calcium carbonate (scale).

Risks and Benefits of Hard Water

Hardness ions in water contribute to sticky soap buildup in showers and on the skin. Soap buildup on the skin inhibits the removal of bacteria and over time could cause serious skin irritations. Soap buildup on hair causes it to look dull, damaged, and lifeless. Clothes washed in hard water look dingy and can feel harsh and scratchy on our bodies. Repeated laundering in hard water will ruin fibers and shorten the life of clothes by up to 40 percent.
When water is heated the minerals are released faster onto surfaces. This causes spotting and filming on household flatware, glassware, and other utensils. Hard water spots may be most noticeable after heated dry cycles in automatic dishwashers.
More serious risks of calcium and magnesium scale build-up occur in or on pipe surfaces, water heaters, plumbing fixtures, heating elements and water using devices. Scale build up can impede water flow in pipes and reduces heat efficiency in hot heat exchanger surfaces like your water heater. This increase operating, and maintenance costs as accumulated scale is a poor conductor of heat. Scale may even breed bacteria!
The human diet does need a small amount of calcium (Ca) and magnesium (Mg). Drinking water high in calcium and magnesium minerals has been said to have a crisp and fresh taste. Some cardiovascular studies suggest that drinking hard water is beneficial to lowering disease mortality.
Everybody uses water. Most households use municipal or well water. One can not weigh the risks versus benefits of hard water without understanding how hard their water really is. Fortunately, there are effective water treatments to reduce hardness.

How do you Detect Hard Water?

Detecting the level of hardness in your water is simple with a free hard water test kit. Once a level of hardness has been established, you can choose the right system for your home. Both salt-based water softeners and salt-free water conditioners are available for consideration.
Additional resources can be found at the EPA Office of Ground & Drinking Water-Local Water Report.

Category: Water Contaminants