Leaking pipes

Water companies have reduced leakage by a third from the 1990s and continue to manage leakage closely. All companies have targets for the amount of water that leaks from pipes.

How can companies be compared?

There are different ways to compare how companies are doing on leakage:

• Comparing how each company is doing against its target

All companies have targets for how much water leaks from pipes – are they meeting, beating or failing them?

Targets differ for each company, depending on how much it costs to reduce leakage in each area and how much extra water from reducing leaking is worth – in money, to the environment and to customers. The targets are approved by the regulator, Ofwat, and set so that bills are no higher than they need to be.

• Comparing companies against each other

Because the size of areas companies supply can vary considerably, the amount of leakage in each company’s area is different. To compare companies against each other, you can either look at how much leakage there is per length of pipe – or how much leakage there is per property.

Why might the leakage levels and targets vary?

Targets for leakage are based on comparing the cost of getting extra water by reducing leakage and the cost of getting extra water from other sources, in each part of the country. So leakage targets, and the level of leakage, will vary depending on local costs and water availability in that region. The targets also include how important customers think reducing leakage is, and this varies across the country too.

Leakage can also vary due to:

• Extreme weather conditions - hot and dry weather or freezing cold leads to the ground expanding or contracting around water mains pipes, resulting in bursts

• The age of the pipe network in a particular region - older pipes tend to leak more

• Pipe material – some materials are more prone to bursting than others

• Differences in water pressure

• Soil conditions - corrosion can lead to some pipe materials being eaten away

• Damage to pipes - in cities and towns, heavy traffic compresses the soil around pipes and can damage them.