Data centre water use: the demand England’s water plan does not count
TL;DR: Data centre water use has moved from a footnote to a planning problem. Water UK warned MPs on 21 July 2026 that single proposed data centres are requesting up to 3 million litres of water a day for cooling, roughly what 3,500 homes drink, while the Environment Agency’s National Framework for Water Resources states plainly that its forecasts exclude emerging demands of this kind. England is already heading for a public water supply deficit of up to 5 billion litres a day by 2055. Where regional headroom is as thin as 2%, the sites that can evidence their own consumption keep their options open.
Last updated: 24 July 2026
Key takeaways
- Water UK told MPs in July 2026 that single proposed data centres have requested up to 3 million litres of water a day for cooling.
- Three million litres a day is roughly the daily consumption of 3,500 homes, drawn by one site.
- The Environment Agency’s National Framework for Water Resources excludes data centre water use from its non-public-supply forecast.
- England faces a public water supply deficit of up to 5 billion litres a day by 2055, plus about 1 billion litres a day for other sectors.
- Public First analysis for Water UK puts current resources at around 420,000 of the 1.5 million new homes targeted this Parliament.
- Continuous flow monitoring gives an estate metered evidence of its own draw rather than an assumed profile.
On this page
What Water UK told MPs about data centre water use
Water UK warned MPs on 21 July 2026 that water resources planning is out of step with the government’s growth agenda, and that individual proposed data centres are asking for up to 3 million litres of water a day for cooling. One building, one connection, drawing roughly what 3,500 homes draw. The argument is not that data centres are the villain. It is that the system rationing England’s water was never asked to count them.
Two claims sit underneath it. First, that England can support only around 420,000 of the 1.5 million new homes targeted on current resources, per Public First analysis. Second, that water companies must plan on assumptions that household consumption falls quickly and business demand declines by 9% by 2037-38. Both assumptions point down. Data centre water use points sharply up, and the stated aim is to triple UK data centre capacity by 2030.
How big data centre water use is in England today
England’s data centres currently draw about 6.6 million litres of drinking water a day, and Water UK expects roughly 19.8 million litres a day if capacity triples as planned. Hold that against the 3 million litre request and the scale problem is obvious: one new site can approach half of England’s entire data centre water use today.
Most of that data centre water use is drinking water, not river or recycled water, on the same networks that supply housing, hospitals and schools. The Environment Agency has been explicit that emerging industries such as data centres and hydrogen production require vast amounts of water to cool their systems, and points businesses towards non-potable alternatives. Recommending an alternative is not the same as planning for the demand.
Why data centre water use is missing from the national plan
Data centre water use is missing because the national forecast says so on the page. The Environment Agency’s National Framework for Water Resources 2025 sets a headline public water supply deficit of 4,940 Ml/d by 2055, and estimates a further 1,090 Ml/d for other sectors by the 2050s. It then rules this category out of that second figure.
Forecasts “do not include new or emerging non-PWS demands such as low carbon energy or data centres.”
Environment Agency, National Framework for Water Resources 2025
What is counted is counted carefully: power generation at an extra 190 Ml/d, spray irrigation at 170 Ml/d, food and drink at 30 Ml/d, chemicals at 20 Ml/d, paper and pulp at 5 Ml/d. Set 3 million litres from one facility against a 30 Ml/d national increase for the entire food and drink sector and the omission stops looking like a rounding error. The framework is honest about it, and its pressures chapter lists cooling data centres alongside a population above 71 million by 2055. It has simply not put a number on data centre water use yet.
What data centre water use means for every other UK site
For a council, a housing provider or an NHS estate, the relevance of data centre water use is not the cooling technology. It is headroom. Water UK puts the buffer between available supply and existing demand at about 2% in parts of England, and the Environment Agency’s own figure is a shortfall of 5 billion litres a day by 2055 for public supply alone, plus 1 billion litres a day for energy, food production and emerging technologies. It expects 60% of that gap to close through demand management and leakage reduction, 40% through new supply.
Read the split carefully. Sixty per cent of the national answer is other users cutting back, which includes your estate. When a demand the plan never counted arrives, and the same plan assumes your commercial water consumption falls by 9%, the pressure to prove your reductions goes up. Assumed savings get challenged. Metered savings do not. It is the shift covered in our note on the water infrastructure MOT: periodic evidence is losing to continuous evidence.
How to evidence what your own site draws
Evidencing site consumption is a four-step job, and none of it requires shutting the building down. The point is to replace an assumed profile with a measured one, so a demand plan, a connection application or an efficiency claim rests on data rather than a benchmark.
- Meter the incomer. Log at the site boundary so total draw is known by the hour, not by the quarter. The Clamp-on Ultrasonic Flow Meter straps to the outside of live pipework from DN8 to DN100, with no cutting and no shutdown, which is what makes it viable on an occupied estate.
- Sub-meter the big draws. Cooling, catering, irrigation and plant rooms behave differently. Splitting them turns a bill into a diagnosis, and it is the basis of water balance monitoring.
- Establish the night-flow baseline. Between roughly 2am and 4am a building should approach zero. Whatever it does not drop to is loss, and it runs all year.
- Alarm the deviation, not the total. Thresholds in the AQUAIOT Cloud raise an alert when the profile breaks. On the escape-of-water side, the NOAH Multifunction Leak Sensor triggers the moment water reaches its leak sensing membrane and runs up to 10 years on its LoRaWAN battery.
None of this changes national data centre water use. It changes whether you argue from a spreadsheet assumption or from a meter when headroom is allocated. Our guides to water demand management and multi-site water monitoring cover building that evidence across a portfolio, and the water leak detection service covers the loss side of the same ledger.
Frequently asked questions
How much water does a single data centre use per day?
Water UK told MPs in July 2026 that individual proposed data centres have requested up to 3 million litres of water a day for cooling, roughly the daily consumption of 3,500 homes. Actual data centre water use varies widely with cooling design, climate and whether the site draws potable or non-potable supply, so a request is an upper bound rather than a typical figure.
Is data centre water use included in England’s water resources plan?
No. The Environment Agency’s National Framework for Water Resources 2025 states that its forecasts do not include new or emerging non-public-supply demands such as low carbon energy or data centres. The framework quantifies spray irrigation, power generation, food and drink, chemicals, and paper and pulp, then leaves this category outside the arithmetic.
How much water will England be short of by 2055?
The Environment Agency projects a public water supply shortfall of up to 5 billion litres a day by 2055 without further action, with a further 1 billion litres a day needed for energy generation, food production and emerging technologies. Data centre water use sits inside that second category and is not separately quantified.
What can a UK estate do about it?
Measure what the site actually draws, continuously, rather than relying on an assumed profile. Continuous flow monitoring at the incomer, sub-metering of the largest draws, a night-flow baseline and threshold alerts give an estate defensible evidence of its own demand, which is the currency wherever headroom is contested.
By Gianbattista Porru, Digital and IoT lead at AQUAIOT. Gianbattista Porru leads digital and IoT delivery at AQUAIOT, working across smart water monitoring, telemetry, and dashboard projects for UK utilities, councils, housing providers, and public-sector estates.