As Great Britain is largely made up of limestone and chalk, around 60% of homes in England and Wales are supplied with hard water. Fortunately for us, there are a number of ways to deal with it.
The simplest and most common way is to treat it with malt vinegar or lemon juice, which dissolve the mineral deposits. This is fine for cleaning out your kettle or polishing your taps and silverware but it is only a temporary, small-scale solution. (It would be quite tricky to clean a large appliance with lemon juice!)
Most homes are in hard water areas, therefore, treatment of water as it enters the house is common practice. This can be done in two ways – water softening and, more recently, water conditioning.
Water softening is the most common method of treating hard water. It works by a fairly simple chemical process – swapping the calcium (which forms limescale) for sodium, (which is more likely to stay dissolved).
- As water enters the domestic system, it passes through an ion-exchange column filled with thousands of tiny beads of resin.
- This resin has charged sodium attached to its surface and it swaps this for the more reactive calcium and magnesium as water flows over it.
- The resin can continue to do this indefinitely as long as it is washed through with salt water every so often to wash off the calcium and magnesium and replace the sodium. Most modern columns will automatically rinse themselves if regularly provided with salt.
Water conditioning follows a far more hi-tech route. Here, a water conditioner is attached to the pipes to expose the water to a low level magnetic or radio field. This field causes tiny impurities in the water to clump together. This will reduce limescale because these clumps form a better surface for the dissolved minerals to stick to than the inner surface of the pipes, making them more likely to stay suspended in the water. If the water is left to stand, the minerals can form a kind of white sludge called ‘soft scale’, but this only accumulates in water tanks and is far easier to remove than a rock-hard layer of limescale.