Hotter UK summers could cause 'vicious cycle' of increased energy and water use

Hotter, drier summers will drive a “vicious cycle” of increased electricity use and emissions, highlighting the urgent need to ‘decarbonise’ the energy system and upgrade the water infrastructure, an IMechE expert has said.

IMechE head of engineering Dr Jenifer Baxter made the comments to Professional Engineering after the publication of the Institution’s new report today, Water: Drought and Flood.

With much of the UK gripped in the longest heatwave since 1976 and higher-than-average temperatures forecast until October, the report looks at the effects climate change will have on the water system and how the government, water companies and engineers can act to counter them.

As the global average temperature rises, British summers will become hotter and slightly drier, increasing water use. Treatment plants will have to run at peak rates for longer, increasing maintenance and running costs as well as energy consumption and chemical use to clean the water faster.

“I think this summer is definitely a reflection of the changing climate,” said report lead author Dr Baxter. “We are using more electricity now than perhaps we would have done… there is a vicious cycle.”

Leaky pipes are an ongoing issue, the report says. United Utilities in the North West of England reportedly lost 18,300,000 litres of water per hour last year, according to a recent issue of Private Eye ­– compared to just 540 litres per hour from a hosepipe, which were temporarily banned for 7m customers.

The rate of pipework replacement must be “significantly increased”, the report says, calling it an expensive but essential task.

With ageing infrastructure and a complex web of responsibilities within the sector, collaboration will be key to tackling the issue, Dr Baxter said. “It is going to be a real requirement to make sure the water keeps flowing… you have got these water engineers, civil engineers, system engineers, all looking at the system, and the way we can make it work much more efficiently is by collaborating.”

While drier weather will mean increased water use and therefore higher costs, the flipside of the extreme weather will likely be intense rainfall. If it falls on hard, dry ground, it can quickly lead to flooding.

New-build homes and commercial buildings should include sustainable urban drainage to counter the risk, the report says, and the government should tell households and businesses how to mitigate the impacts of poor drainage.

Other recommendations include for all major UK cities to publish research on what their infrastructure needs to cope with the changes to water use and demand, including the promotion of ‘grey water’ recycling – from sinks, washing machines and businesses – to fill toilets, and the creation of a water industry forum supported by Water UK and the National Infrastructure Committee, to write a water infrastructure sustainability plan for industry including the joint risks of drought and flood.