The UK's AI ambitions are being held back by a shocking oversight: the government's failure to account for water resources in its plans. Water UK, the trade body representing Britain and Northern Ireland's water companies, has sounded the alarm on this critical issue, pointing out that policy documents on AI growth zones, the AI for science strategy, and the AI opportunities action plan make no mention of datacentre water demands.
Datacentres, which are crucial infrastructure for AI, rely heavily on water for cooling systems to manage the intense heat generated by their densely packed servers. In fact, a significant portion of datacentre water usage is indirect – linked to their high electricity needs rather than direct consumption in cooling towers and chillers. Water UK highlighted this worrying trend in a briefing to MPs, where it emerged that existing policy documents have ignored the substantial water demands of datacentres.
The Environment Agency's national framework for water resources, published in June 2025, also failed to provide an estimate for datacentre water consumption – a glaring omission given that over three-quarters of existing datacentres are situated in water-stressed regions such as the South and East of England. These areas have struggled with prolonged periods of extreme heat and low rainfall, leading to hosepipe bans affecting millions of residents.
Water UK has warned that continued datacentre expansion in these regions may become impossible without significant policy adjustments, citing existing pressure on the network. While water companies have reduced leakage by around 40% since privatisation and aim for a further 17% cut by 2030, Greenpeace recently argued that the volume of water lost through leaky pipes far exceeds potential savings from national hosepipe bans.
The issue is particularly acute in Slough, home to the UK's highest concentration of datacentres and served by Affinity Water. The company informed MPs in May that some 125 proposed or under-construction datacentres are requesting up to 3 million litres of water daily – equivalent to the peak water demand of 3,500 homes. This volume is a huge concern, especially as current Environment Agency permits require datacentres to use drinking water only, amounting to an estimated 6.6 million litres of drinking water daily across England. If the government's ambition to triple datacentre capacity is met, this figure is projected to triple to 19.8 million litres a day by 2030.