The Water Research Centre consultancy estimated in February that centres in England currently use about 1.9bn litres of drinkable water a year – around 0.2% of the non-household market.
The company says there is a “clear upward trend”, external in the use of water.
The Greens cited research by Global Action Plan, , externalan environmental charity, which suggested large centres could consume 1.5m litres per day.
The party said data centres should be built on brownfield sites, near to renewable energy sources to allow them to use renewables when possible.
The Greens also want owners to provide annual figures on water and electricity consumption.
But the government said much more water – roughly a fifth of the supply – was lost through leaks.
A government spokesperson said: “A pause on building new data centres would simply send investment and good jobs abroad, while leaving Britain dependent on overseas computing for the processing of sensitive health and defence data.
“Put simply: it would be a disaster for jobs and national security.
“That said, this does not mean a blank cheque for Big Tech or that every data centre should be approved.
“Developers must plan to use clean power, use water responsibly, create British jobs and supply chains, and provide investment to the communities in which they are built.”
Rosa Curling, co-executive director of the campaign group Foxglove, said: “Any action to pause or slow down this construction frenzy is positive, but the reality is that the government and local authorities already have the power to say that data centres can only be built if tech billionaires, not the British public, pay for their costs in full.
“As a minimum, no hyperscale data centre should be given the go-ahead unless the developer also builds new renewable energy and storage to power it completely – and commits to not draining local water supplies.”
