The dried up bed of Yarrow Reservoir near Bolton, England, in July 2018, in the midst of a heatwave.
PHOTO: Christopher Furlong/Getty Images Europe/Getty Images
The dried up bed of Yarrow Reservoir near Bolton, England, in July 2018, in the midst of a heatwave.
(CNN) —  

Climate change and rapid population growth could leave England facing severe water shortages in the next 25 years and thrust the country into the “jaws of death,” the head of the UK Environment Agency warned on Tuesday.

Unless England cuts down on its water use, the country will not have enough clean water to supply its needs, Sir James Bevan told the Waterwise conference in London.

“Demand for water will rise as the population grows, whilst water supply is likely to reduce as the effects of climate change kick in,” Bevan said.

“Around 25 years from now, where those two lines cross is known by some as the jaws of death – the point at which we will not have enough water to supply our needs, unless we take action to change things,” he added.

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The UK population is projected to grow rapidly, from 67 to 75 million by 2050, putting significant strain on water supply, said Bevan, adding that a person’s daily water use could be cut from 140 to 100 liters in the next 20 years.

“There are simple steps we can all take…Get a low flush toilet. Take short showers, not deep baths…Don’t water your lawn: it will survive without you. It’s not rocket science,” he said.

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01:39 - Source: CNN
How can I use less water?

’Existential threat’

Population growth combined with climate change form an “existential threat” for the UK, according to Bevan.

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By 2040, more than half of UK summers are predicted to be hotter than in 2003, and rivers’ water supply could fall by between 50-80%, he said.

England could avoid the “jaws of death” by urgently reducing water waste from leaking pipes and investing in new desalination plants, according to Bevan.

“We need to change our attitudes to wasting water so it becomes as socially unacceptable as throwing your plastic bags into the sea. We need to use less water and use it more efficiently,” he said.