Another Good Reason Why We Don’t Need Immigration

London could face “severe” water droughts as the capital’s population grows, leading professors have warned.

Office for National Statistics figures predict London’s population will exceed 10 million in 2035, by which time an estimated 50,000 homes are expected to have been built.

The population was 8.1 million in the last census in 2011.

Civil engineering experts from two of London’s top universities have said this level of growth will mean Londoners need to start thinking seriously about how they can save water.

Professor Adrian Butler of Imperial College London is leading the Community Water Management for a Liveable London (Camellia) project. This aims to solve how London’s water supply can be sustained in future.

He told the Standard: “The concern of drought in London is a real one and will become more and more challenging as time goes on.

“The worry has always been relying on rain in winter, when the water doesn’t evaporate as much as in summer. If you have a succession of dry winters, you are facing catastrophe in summer.

“When you look at the anticipated growth of London’s population, it’s huge. Demand will rise and the challenge then will be to use water more effectively.”

One of Camellia’s solutions is grassroots action. Southwark’sKipling Estate, in the shadow of The Shard, is set to install a community garden, with Camellia leaders to install a tank to collect rainwater.

Prof Sarah Bell, of University College London, is leading the project after similar success in the nearby Meakin Estate.

She said: “Instead of the water running off the roof, it will be collected in the tank to water the garden – which reduces the demand on drinking water.

More people need to be on board. No one wants to waste water. We’re trying to start a conversation so people can learn more about where it comes from and where it goes to.”

Prof Bell ruled out the possibility of “day zero” – as mooted in Cape Town last year when authorities threatened to turn off taps because water levels were so low – because the UK has comparatively stable governance.

But she warned: “London could face severe drought. If we don’t want to get to that point, we need to prepare for it now.

“We need to make sure Londoners are ready. If it doesn’t rain in winter, as has been the case this week, it can put our water resources under pressure.

“The growing population means all of us need to use less water.”

Last year it emerged that bosses at Thames Water are planning to turn sewage into drinking water as part of a series of measures to stop taps running dry.

They want to open the country’s first effluent “reuse” plant at the Deephams Sewage Treatment Works near Edmonton, north-east London, to make sewage waste clean enough to drink.