Hard Water Stains Explained

A few people have asked me recently what hard water actually is, and what the stains are made of. So, I thought I'd lay out exactly what they are, and why they can be such a problem for us around the home.

Hard water contains dissolved calcium and magnesium ions. Commonly referred to as "hardness minerals," dissolved calcium and magnesium can cause numerous problems when present in a water supply.

As water falls from the sky in its various forms, it absorbs carbon dioxide in the air and becomes slightly acidic. Water in this weak acid state reaches and enters the ground. Since it is acidic, it absorbs calcium and magnesium, among other things, from the layers of rock through which it passes.

The minerals neutralize the waters acidity but also make it hard. Then the water finds its way into larger bodies of water both above and below ground, and eventually into our homes.

Water hardness is typically measured in "parts per million," an indication of the quantity of dissolved calcium and magnesium the water contains. In amounts as small as one part per million, water is classified as "hard" to a certain degree. Most homes use water that is considerably harder.

While many families choose to soften their water by removing the calcium and magnesium with home water treatment equipment, many don't even realise they have it in the first instance, however there are some easy ways to prevent it.

Facts:

Studies indicate that 85% of US homes and 60% of homes in the UK are supplied with hard water. Hard water costs you money, causes soap scum and scale, and reduces the efficiency of water-using appliances. Hard water stains occur when the water evaporates leaving behind the mineral deposits causing unsightly stains around taps, faucets, sinks, showerheads, tiles and on carpets.

To check whether the area you live in has hard water, check out your local regional information.

If you have any questions about the hard water in your area, drop me a line at support@hardwaterstainstips.com, or post a blog comment here and I'll get back to you asap.

Regional Information

Hard water in the US

According to the United States Geological Survey, 89.3% of US homes have hard water. The softest waters occur in parts of the New England, South Atlantic-Gulf, Pacific Northwest, and Hawaii regions. Moderately hard waters are common in many of the rivers of the Tennessee, Great Lakes, Pacific Northwest, and Alaska regions. Hard and very hard waters are found in some of the streams in most of the regions throughout the country. Hardest waters (greater than 1,000 mg/L) are in streams in Texas, New Mexico, Kansas, Arizona, and southern California.


Hard water in Canada

Prairie provinces (mainly Saskatchewan and Manitoba) contain high quantities of calcium and magnesium, often as dolomite, which are readily soluble in the groundwater that contains high concentrations of trapped carbon dioxide from the last glaciation. In these parts of Canada, the total hardness in mg/L calcium carbonate equivalent frequently exceeds 200 mg/L, if groundwater is the only source of potable water.


Hard water in England and Wales

Information from the British Drinking Water Inspectorate shows that drinking water in England is generally considered to be 'very hard', with most areas of England, particularly the East, exhibiting above 200 mg/L as calcium carbonate equivalent. Wales, Devon, Cornwall and parts of North-West England are softer water areas, and range from 0 to 200 mg/L. In the brewing industry in England and Wales, water is often deliberately hardened with gypsum in the process of Burtonisation.



Hard water in Australia

Analysis of water hardness in major Australian cities by the Australian Water Association shows a range from very soft (Melbourne) to very hard (Adelaide). Total Hardness as Calcium Carbonate mg/L are: Canberra: 40; Melbourne: 10 - 26; Sydney: 39.4 - 60.1; Perth: 29 - 226; Brisbane: 100; Adelaide: 134 - 148; Hobart: 5.8 - 34.4; Darwin: 31.