"Thirsty data centres are sucking up Britain’s scarce water supplies", June 27, 2025

Britain’s data centres are consuming close to ten billion litres of water a year at least as the country braces for widespread drought, The Times can reveal.

Two regions are in drought, with more likely to follow, raising the possibility of summer hosepipe bans as rivers hit “exceptionally” low levels, highlighting the squeeze on Britain’s water supplies despite its rainy reputation. Yet there is no official estimate of how much water the nation’s 450-plus data centres are using to keep their servers cool.

The chairman of the Environment Agency (EA) has warned that England is heading for a national shortfall of five billion litres of water a day by 2055, more than a third of the 14 billion litres a day used now. But that is without factoring in the rapid rise of thirsty generative AI tools, such as ChatGPT.

The British tech industry and the EA have been working in recent months to gauge water demand from data centres today and in years to come. Neither will publicly disclose a figure on data centres’ water use.

However, figures released under transparency laws suggest that water companies are already supplying at least almost ten billion litres a year to 231 data centres, the equivalent of 3,980 Olympic swimming pools. The snapshot, obtained by the technology campaign group, Foxglove, and The Times, suggests Thames Water is far and away the biggest supplier of water to data centres.

About half of the UK’s water companies were unable to provide figures to Foxglove, in part because data centres do not have to report their water usage. “It is deeply alarming that over half our water companies have no clue how many data centres they supply, nor how much water they are hoovering up,” Donald Campbell, of Foxglove, said.

This information void exists as the government eyes data centres as a totemic part of its economic growth plans. Labour has said AI will “turbocharge” growth, with £39 billion committed for more data centres in the next five to ten years.

...

...

Just how bad is water use from data centres?

Britain’s data centres are mostly running servers powering websites, cloud storage and the latest hit series on Netflix. However, servers running AI models are much more water intensive.

...

Some experts think the fears over water use are overwrought. Henry Shevlin, associate director at the University of Cambridge’s Leverhulme Centre for the Future of Intelligence, noted most things of economic value consume water, from agriculture to football matches, and data centres running AI models are neither an exception or an outlier.

...

Still, he said the tech industry should be more transparent about water use in Britain and the government could demand more openness. ...

What comes next?

Growth in AI is “likely to result in a large and rapid increase in the number of data centres in England”, the Environment Agency said... The concern, it said, is many will be built by 2030, before new reservoirs and water transfers are complete. Britain’s first new reservoir in more than three decades, Havant Thicket near Portsmouth, will not be full until 2031, for example.

Angela Rayner, the deputy prime minister, has recently overruled local councils to give the green light for building new data centres, once at Iver in Buckinghamshire last December and this May for one at Abbots Langley in Hertfordshire. Water industry sources believe new data centres in the next five years could need the same amount of water as 500,000 people.

Thames Water said southeast England was already water-stressed and the region was earmarked for a large proportion of proposed new data centres.

“This brings a challenge between safeguarding our finite [water] resources while supporting the UK’s growth strategy,” a Thames Water spokesman said. Water UK, the industry body, said: “We need planning hurdles cleared so we can build reservoirs quickly”. An EA spokesman said: “We are working with the technology sector to understand their needs, to help develop sustainable solutions.”

Campbell said: “Water companies and the government are walking into this future with a blindfold on. Ministers and water companies need to wake up — the likes of Amazon, Microsoft and Google must not be given carte blanche to drain our rivers and streams.”