Last week’s rainfall in Slough offered little relief to the broader water scarcity challenges facing southern England, where prolonged heatwaves have led to persistent hosepipe bans and diminishing reservoir levels. Thames Water reports its reservoirs at 74 percent capacity—well below the typical 87 percent for this time of year—reflecting ongoing pressure on regional water supplies. Residents are urged to conserve water through measures such as shorter showers and limiting outdoor use, but not all users are constrained by these restrictions.

Slough, a significant hub for the UK's fast-growing data centre industry, hosts 32 such facilities, primarily located in the Slough Trading Estate’s industrial zone. Unlike households, commercial users—including data centres—are exempt from hosepipe and sprinkler bans, allowing them unrestricted water consumption. This exemption has raised concerns among residents and industry observers, as data centres are known for their substantial water and energy demands.

Data centres consume large volumes of water for cooling purposes, especially during hot weather, when the need to dissipate heat generated by intensive computing rises sharply. While approximately half of UK data centres rely on air cooling, larger installations frequently use water cooling systems that depend on evaporation, significantly increasing water consumption. A survey by industry group TechUK indicated that among 72 surveyed centres, one in 25 uses over 100,000 cubic meters of water annually, a volume comparable to England’s 2,200 golf courses combined. However, data on the wider sector remains limited, as the majority of over 500 UK data centres have not publicly disclosed their water usage.

The energy demands of these facilities are equally striking. Data centres in Slough account for an estimated 65 percent of the town’s electricity consumption. Nationally, the sector consumed approximately 2,400 gigawatt-hours in 2024—around two percent of the country's total electricity use. This figure increased to 2.5 percent as of last month, according to statements from Energy Minister Lord Hunt. Growth is expected to continue with the government’s ambition to triple the number of UK data centres by 2030, a policy criticized for neglecting the implications for water and power infrastructure.

Artificial intelligence (AI) technologies, rapidly expanding within these centres, exacerbate resource demands. A 2023 University of California study estimated that data centres use the equivalent of a half-litre of water per 10 to 15 AI processing tasks, with power usage rising in step with the complexity of AI models. Separate research from the Massachusetts Institute of Technology highlighted notable increases in electricity consumption between iterations of AI systems such as Meta’s Llama 3.

Concerns over resource stress have been echoed by Water UK, the water industry's trade body, which warned the government’s strategy fails to adequately consider data centres’ water needs. The group highlighted that water scarcity is already impacting housing developments and business expansions and noted that data centres enjoy planning advantages due to their designation as Critical National Infrastructure. This status fast-tracks project approval while allowing data centres to circumvent restrictions imposed on other developments due to resource constraints.

In North Lincolnshire, where the government has designated a growth area for data centres, planning approval was recently granted for the Elsham Tech Park, poised to become the largest in Britain. Although the developers propose a “closed loop” water cooling system designed to minimize consumption, experts caution that such systems markedly increase energy use. To support this massive energy draw, the plan includes a gas power station supplemented by 650 diesel generators, raising environmental concerns due to emissions.

Similar tensions exist near London, where a new data centre has been permitted on Green Belt land despite longstanding protections aimed at preserving limited green spaces and the area's ongoing water stress. Critics argue the rush to position the UK as a leader in AI overlooks the broader impact of data centres on critical infrastructure, including water resources, energy supply, and local communities.

As Britain confronts aging and insufficient infrastructure—marked by a lack of new reservoirs in decades and the early closure of coal-fired power stations—experts warn that unchecked expansion of water- and energy-intensive data centres could deepen existing shortages. The government’s drive to foster a digital economy and AI innovation underscores the need for integrated planning that balances technological growth with prudent resource management. Without such coordination, residents may face ongoing restrictions on basic water use while the demands of data centres continue to rise.