Water hardness is the result of detectable levels of calcium and magnesium in water. Both of these minerals are commonly found in certain rock layers and enter groundwater in this way. These minerals are essential for humans, however the human body only absorbs and utilises minimal concentrations. Hard water is therefore not harmful, but it is not particularly important for the human body either. However, when these minerals settle in the pipes as limestone, damage can be caused to household appliances like coffee machines and washing machines.
Water hardness: what causes hard water?
Before water was extracted from wells, humans secured their supply of this vital element from rainwater. The human body therefore adapted to relatively low levels of minerals in water. It was only later that wells were constructed, which allowed water to flow through various rock layers and go through a natural filtering process. Groundwater extracted in this way has a fairly high mineral content due to the natural filtering process: as water percolates the rock layers, water-soluble minerals like calcium and magnesium enter the groundwater and thus the tap water.
Is hard water harmful or healthy?
A higher degree of hardness, i.e. a higher concentration of magnesium and calcium, is not a threat to the human body. Hence, minerals are not removed by water companies before the water is supplied to households as drinking water.
Even so, water containing minerals is of no use to humans, who cannot properly absorb them and so excrete them. It is mainly through food that important nutrients are supplied to the body.
Risk of kidney damage from very hard water has not been ruled out
If too much magnesium and calcium is introduced to the body through hard drinking water, this puts your kidneys under pressure. The kidneys are responsible for excreting minerals and salts which cannot be utilised by the body.
Water hardness in the UK
In the UK, water hardness is generally measured in milligrams per litre (mg/l). According to the DWI (Drinking Water Inspectorate), soft to moderately soft water contains 0-100mg/l of calcium carbonate, slightly to moderately hard water contains 100-200mg/l, and hard to very hard water contains over 200mg/l.
Thames Water estimates that as much as 60% of the UK is classed as having hard or very hard water. Generally, water is hardest in the south of the country due to the chalk and limestone regions there, and becomes softer moving north. However, hard water areas may have pockets of soft water and vice versa, so testing is needed for an accurate measurement.
Test water hardness and lower your energy bill
Experts do not believe that hard drinking water is necessarily a threat to our health. You can find more information on this topic in the IVARIO drinking water blog.
Despite this, it is interesting to know whether your water is hard or soft. This information can help you to extend the life of your household appliances and even lower your energy bill. This is because limescale deposits often lead to a higher electricity consumption and can also affect the taste of the water. As well as testing water hardness, in many cases it is advisable to test the quality of your tap water. To do this, we recommend out Combined Test, which tests extensively for heavy metals, bacteria/germs and salts.