HARD WATER

How it Affects Our Daily Lives

Simply stated, water hardness refers to the amount of calcium, magnesium, carbonate, and sulfate dissolved in the water entering your home or business. When hardened water becomes over saturated with minerals, is heated, or is placed under the increasing pressure of smaller water pipes, the dissolved minerals come out of solution (precipitate) and attach to our plumbing and hot water appliances. Hard water minerals can precipitate out of solution anywhere in our plumbing system. However, the heating of hard water is responsible for most of the damage caused to hot water heaters and other appliances as well as the unsightly scale we observe on faucet screens and shower heads.

Water hardness depends on your location and water source. Typically, water from underground sources such as wells and acquafers is harder. To determine how hard your water is, call your local water company and ask for the water hardness in grains per gallon (gpg) or milligrams per liter (parts per million/ppm). As an alternative, order a free water test simply by mailing me a request. Use the following chart to determine the extent of your hard water problem:

How Water Gets Hard

The best way to explain how water gets hard (ladened with potential damaging minerals) is to start with rain water which is naturally soft, having less than 1 grain per gallon (gpg) of dissolved mineral. Rain water is called a "universal" solvent because of its natural ability to clean. Water forms when water vapor in the air interacts with particulate mater to form raindrops. As rain falls, it absorbs other materials, some of which cause the water to form a slightly acidic pH. This primes the water droplet with an extra measure of solvency. The solvency characteristics of rain water are further enhanced when the rain water interacts with polluted air and, while on the ground, flows through environments which further acidify it. When water flows through and over areas consisting chiefly of calcareous and other limestone based rocks, these calcium and magnesium carbonate surfaces, which normally would not dissolve in water, are affected by the acidic water which turns carbonates (insoluble) into bicarbonates (soluble). Thus, surface salts which normally would not find their way into our water, are trapped and carried as unwilling passengers in the form of calcium (+) and carbonate (-) ions. The minerals are surrounded by water molecules and carried as complexes within the water.

As the water continues to flow to its final resting point, it dissolves additional minerals but at a decreasing rate. This is because the dissolved minerals cause the surface tension of the water to increase thus decreasing the water's ability to dissolve additional material. The hardness of water flowing into your house or business depends on the extent of its exposure to surface and sub-surface rocks and limestone structures and the extent to which it was subjected to acidic influences. The hardest water comes from wells and aquifers. However, some wells are exceedingly soft while some public water supplies are exceedingly hard. About 3/4ths of the country is plagued with problematic water hardness.

Why Dissolved Minerals Solidify in Our Plumbing and Appliances

Dissolved minerals, primarily bicarbonates of calcium and magnesium, remain within their host complexes under normal conditions. As a result, the dissolved particles, devoid of any nucleation centers for growth and escape from the water, flow evenly within the water having no particular tendency to bind together or lose their solubility. However, when the mineral content of the water becomes over saturated, is heated, or placed under pressure, the complexes become agitated, break up and the (+) and (-) ions lose their polarity allowing the minerals to clump into larger masses. The clumping effect makes it more difficult for the minerals to remain soluble and the crystallized mineral precipitates out of solution. Two types of crystallization occur.

The first, which occurs in the hottest part of the heat exchanger (hot water heater heating element, for example), results in a mineral form called calcite. Calcite is an adherent mineral that attaches itself to the surface of the heat exchanger. Repeated collisions cause the build up of more and more scale on the heat exchange surface. Since mineral scale is an insulator, transfer of heat from the heating element to the water is gradually reduced causing more energy to be consumed to heat the same water. This is why scale build-up on your water heater's heating element can increase your energy bill by 10% to 40%..or more!


The second type of crystallization occurs when carbonate forms in a lower heat environment away from a heat exchanger. The resulting mineral formation is called aragonite. While aragonite can still adhere to surfaces (faucet screens and shower heads for example) its primary form is non adherent and tends to form smaller grained or softer scale deposits. These deposits remain stable upon heating and can be carried throughout the heating or cooling system causing little or no damage. This type of scale is what collects at the bottom of your water heater, becomes trapped in faucet mounted filters, appears as toilet bowel discoloration ⁽¹⁾, or moves through and out of your home through the water pipes.

 Why We Should Be Concerned About Hard Water

Hard water leads to higher energy costs to heat water. The US Department of Energy (DOE) reports that as little as a 1/32 inch scale build-up on a heat exchange surface (hot water heater, boiler, cooling tower, etc.) causes you to use almost 10% more energy. A 1/4 inch build-up will increase energy consumption by a whopping 40%! This can cost hundreds or even thousands of wasted energy dollars per year for home or business.