Water faucets are one of the places homeowners may notice the effects of hard water (Photo: Susan Boser, Penn State)
Do you notice white scaly buildup on your pots and pans and inside your coffee pot? Do your faucets have a crusty sediment on them? Is your white laundry looking a bit more dingy and not quite as white as you’d like? Chances are you are dealing with hard water. Hard water, while not harmful for human consumption, can wreak havoc on any appliances where water is heated and even reduce their lifespan or effectiveness.
Hard water comes from the minerals calcium and magnesium that are naturally found in the underground rock layers that groundwater wells are tapped into. Hard water can be found in wells of individual homeowners and in larger sized wells that can serve entire community water systems.
The hardness of water is measured as parts per million of calcium and magnesium, or as grains per gallon (GPG) of those same substances. Water that is over 120 parts per million, or over 7.0 GPG is considered hard by drinking water standards. Water testing can be done to find out the hardness level of your water.
It is a personal preference for most people on whether they want to treat their water to remove the hardness. If you choose to remove the hardness from your water, a traditional ion exchange water softening unit is the most effective way to do so. In these units, the negatively charged calcium and magnesium ions in the water are exchanged with the positively charged ions in sodium.
In a traditional water softening unit, the hard water passes through a resin that has been coated with the positively charged sodium ions. As the water washes over this resin, the ions exchange places and this resulting water loses its ability to form scale buildup on appliances and in pipes. The water is now considered softened. These units are larger, point of entry water treatment systems meaning that they will treat all of the water that is coming into the home.
Maintenance on softener units requires the homeowner to keep the unit sufficiently full of salt pellets for keeping the resin charged. Most softening units will automatically backflush on a regular basis to maintain the resin’s positive charge. This process using sodium will add an amount of salt to the water, not so much that it can be tasted, but enough so that if a person is following a low salt diet, they may want to choose potassium pellets for system recharge instead. The ion exchange process will work the same, but without the addition of sodium to the water.
Other non-traditional softening units using magnets, electronic charges, or citric acid to remove hardness have shown mixed results of effectiveness and are not generally recommended.
If your water has been found to contain bacteria or high amounts of iron, these issues must be addressed first and treated with filtration before the water enters a water softening unit.
As with the purchase of any water treatment equipment, have the water tested by an independent lab before making a decision on treatment methods. Get a warranty on treatment equipment and find out maintenance requirements of the unit you are planning to install. There is no single kind of treatment system that will solve all of your water issues, so be sure to research any purchase carefully.
For more information, see the article on water softening.