The British Dam Society
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About Dams

Back to usesUses for Reservoirs - Water Supply

Reservoir water can be used to supply water to our homes and factories. Reservoirs are designed to store the rain that falls during the wetter parts of the year, so that there is a continuous supply of water for the drier periods.

Godley Service Reservioir during construction

Godley Service Reservioir, near Manchester,
NW England during its construction

The water from reservoirs must be cleaned before it is used. This is done at a water treatment works. Chemicals are added to help remove unwanted naturally occurring mineral particles and harmful bacteria. Dirt and other small particles are usually removed by filtering the water through beds of sand and gravel, or by adding chemicals that cause the particles to stick together so that they can be separated off from the water.

Once the water is treated, it is transferred to a service (or storage) reservoir ready for distribution. Service reservoirs are covered reservoirs. In the UK, there is a network of tens of thousands of kilometres of underground pipes that carry billions of litres of clean water every day to homes, offices, schools, factories and hospitals.

Find out more about water treatment and its distribution.