Within 25 years England will not have enough water to meet demand, the head of the Environment Agency is warning.
The impact of climate change, combined with population growth, means the country is facing an "existential threat", Sir James Bevan told the Waterwise Conference in London.
He wants to see wasting water become "as socially unacceptable as blowing smoke in the face of a baby".
"We all need to use less water and use it more efficiently," he said.
Sir James Bevan was appointed chief executive of the Environment Agency - the public body responsible for protecting the environment and wildlife in England - in 2015 after a career as a diplomat.
He told his audience that, in around 20 to 25 years, England would reach the "jaws of death - the point at which, unless we take action to change things, we will not have enough water to supply our needs".Image caption
'Use 40 litres less a day'
Alongside action being taken by the government, water companies and regulators, Sir James wants the public to use less water, and use it more efficiently.