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Water hardness

Hard water, or water hardness, is a chalky deposit caused by hardness levels. Most water in the South-East of England is hard in nature.

It’s caused by minerals such as calcium and magnesium. This is a natural occurrence in the geology of the landscape. We are unable to control water hardness as it’s a characteristic of the water at source.

Research shows that minerals in hard water is good for us, especially for our bones. It’s not considered harmful.


Different types of hard water

We source 65% of our water from local rivers and 35% from natural reservoirs underground. This means it passes through soft chalky limestone many times. That’s why all the water in our region is hard.

Hard water can be broken into different categories and varies based on the local geology.

Hardness of water
Water hardness (mg/l CaCO3)
 Soft  up to 100
 Slightly hard  100 -150
 Moderately hard  150 - 200
 Hard  200 - 300
 Very hard  More than 300

How to reduce the affects of hard water scale

Hard water can sometimes leave behind a chalky residue called limescale. To prevent this, you can:

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Reduce the temperature of your hot water to 60 degrees
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Put a steel scale collector in your kettle
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Empty your kettle if you're not using it for a while
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Install a water softener on household appliances*

*Please note we don’t recommend using the softened water for drinking or cooking. We advise a separate tap to be installed. Also, an inspection of your domestic plumbing system and softening unit. This should be done by an approved plumber. 

To reduce the build-up of scale deposits, you can install an electric descaler such as Scaleguard.