As the hosepipe ban comes in to force this week, figures from industry regulator Ofwat revealed Thames Water, which serves Richmond, topped the leak table of British water companies.

The company has a 25.7 per cent leak rate and reportedly loses 665m litres of water a day and could fill Wembley Stadium every 36 hours through the leaks.

Southern Water, South East Water, Anglian Water, Sutton and East Surrey, Veolia Central and Veolia South East were also imposing the hosepipe ban, but their average leak rate was 17.7 per cent.

A Thames Water spokesman said: “While in the Home Counties it is comparatively easy to dig up a road and repair a broken pipe, doing the same job in busy central London can be a lot trickier.

“Leakage from our 20,000-mile network of mains is currently down a third to its lowest-ever level since its peak in 2004 as a result of us replacing 1,400 miles of worn-out Victorian pipes, mainly under London.

“We have hit our annual leakage-reduction target, agreed with Ofwat, for the past five years running and we are in line to hit a sixth by a margin of about 30m litres a day.”