Thames Water is considering a ban on watering gardens and washing cars from August, after the driest winter for 100 years and the recent heatwave.

The move emerged as the German-run utility ramped up bills by 16% in Newbury to pay for new water pipes in London. London’s Victorian sewerage system is thought to leak enough water every day to fill 366 Olympic swimming pools.

June rainfall for the Thames Valley was only two thirds of normal, and there have been eight consecutive months of below-average rainfall. Thames Water is splashing out on a radio advertising campaign, encouraging us to turn the tap off when brushing teeth, stop using sprinklers, and water the garden with washing-up water.

John Halsall, Thames Water’s Head of Water Operations, said: “We saw little more than half the usual winter rainfall, which is vitally important because it replenishes supplies. The dry weather has continued and, despite recent rainfall, last month we saw only two-thirds of the expected average rain.

“We may need to impose restrictions on water use – such as a hosepipe ban – later in the summer, so it is important that we all do what we can to save every drop now.”