All the water supplied by Bristol Water is either hard or very hard. The hardness is completely natural; it’s simply as a result of the geography and geology of the area. Naturally occurring calcium and magnesium salts dissolve into the water as it moves over and through the ground. The level of these salts in the water determines its hardness. The information in the following table provides a general rule for classifying water hardness:

The information above can help you in setting-up machines like dishwashers that have in-built water softening devices. To find out the hardness of your water supply, please use the postcode search function.

Water hardness is not harmful to health and does not indicate deterioration in your water supply, there are currently no regulatory limits for water hardness. However, hard water can lead to limescale formation and may also affect the appearance of hot drinks and increase the amount of detergent and soap used. Limescale will form in kettles, irons, washing machines and the hot water system, anywhere the water is heated.

New kettles, particularly plastic ones do not collect scale around the element. When the water is boiled the limescale floats freely in the boiled water. These tiny particles of scale react with natural products in tea and coffee producing a scum on hot drinks. This effect can be reduced by regularly rinsing your kettle.

Limescale can also build up in hot water cylinders of old-style heating systems. However, combi boilers and electric showers, which heat the water directly, can give rise to small particles of scale remaining suspended in the water. This can sometimes aggravate existing skin conditions such as eczema. Lowering the temperature of your hot water to 60°C can reduce the amount of limescale formed.

Hard water does provide some benefits. If your plumbing system uses copper or lead pipes the hardness salts can create a protective layer on the internal surfaces reducing the amount of metals that can dissolve into the water.

Some customers do not like hard water or its effects. Depending on the goal you are aiming to achieve there is a number of products available that condition or soften the water. Bristol Water does not recommend any specific conditioning or softening devices. If you would like to discuss the different types of devices please contact us for further information.