AI’s thirst: Data Centers, Water Resources and the Fight for the Future

Artificial intelligence (AI) may feel virtual, yet the infrastructure behind it is anything but. As data centers expand across water-stressed parts of Britain, they are colliding with a system already under strain from climate change, ageing pipes and rising household bills.

AI is often described as invisible: algorithms, code and neural networks humming quietly in the cloud. But behind every AI query lies a deeply physical reality. Vast halls of servers, packed with chips, draw enormous amounts of power and they need cooling.

Cooling is where AI collides with one of Britain’s most pressured natural resources: water.

The growth of data centers

Britain is rapidly becoming a hub for digital infrastructure. Dozens of new data centers are planned or under construction, many clustered around London and the south-east. By some projections, national data center capacity could more than double over the next decade as businesses race to adopt AI.

Depending on design and location, a single megawatt of computing capacity can require millions of liters of water a year, particularly where conventional evaporative cooling systems are used. Altogether, UK data centers already consume millions of liters of water each day, though usage varies widely depending on technology, season and local climate.

A system already under strain

This expansion is happening at a precarious moment. The Environment Agency has warned that England could face a public water shortfall of five billion liters a day by 2055 unless urgent action is taken. Climate change is intensifying droughts, population growth is pushing up demand, and decades of under-investment have left pipes leaking at scale.

Data centers are not the sole cause of Britain’s water crisis. But they are becoming part of it.

The pressure is unevenly distributed. Many large data centers are concentrated in regions already classed as water-stressed, particularly around London and the south-east. The result is growing competition between households, farms, rivers and industry for the same limited resource.

Ecological consequences

The environmental stakes are high. Abstracting more water from rivers during dry periods risks damaging already fragile ecosystems. Evaporative cooling systems, still common globally, consume water by releasing it into the atmosphere, meaning it does not return to rivers or aquifers. As heatwaves become more frequent, the risk of ecological harm rises, precisely when the demand for cooling is greatest.

How tech giants are responding

The world’s largest technology companies are increasingly aware of the scrutiny. Microsoft, Google, Amazon and Meta dominate the AI landscape, and their data centers account for a significant share of global computing.

Several hyperscalers now publish water-use data and have pledged to become “water positive” by 2030, replenishing more water than they consume. Some have begun switching to air-based or closed-loop cooling systems, which drastically reduce freshwater use, and investing in projects that reuse treated wastewater instead of drawing from rivers.

These steps matter. But uptake is uneven, and voluntary commitments alone may not be enough in regions already facing chronic shortages.

Water, poverty and fairness

For many households, water is not just an environmental issue. It is a financial one.

Water debt has become one of the most widespread forms of household debt linked to poverty. Citizens Advice estimates that one in six households struggles to pay their water bills, with millions already in arrears. Ofwat has approved bill increases across England and Wales, with the average household facing an extra £123 a year from April 25 and significantly more in some water-stressed regions.

As infrastructure costs rise, much of the burden is being passed on to consumers — often those least able to absorb it.

The reservoir debate

These tensions are playing out sharply in Oxfordshire, where Thames Water is pushing ahead with plans for a vast new reservoir near Abingdon. Known as the South East Strategic Reservoir Option, the scheme is designed to supply millions of people across the region and bolster resilience against drought.

Supporters argue that large reservoirs offer something no other solution can: long-term physical storage to capture winter rainfall and supply dry summers in a changing climate. However, opponents warn of destroyed farmland and habitats, carbon-intensive construction, and spiraling costs. Estimates suggest the project could cost between £5.5bn and £7.5bn, with customers paying higher bills years before any water flows.

No single solution