The Rest Is Politics - Data Centres vs. Drinking Water: What Matters To Us Most?

Episode Date: July 30, 2026

To hear the full episode, which includes an interview with global water expert, Sandra Postel, sign up at the therestispolitics.com With the government quietly categorising data centres as ‘critical infrastructure’, could we ever be in a situation where data centre water supply is prioritised over the water that comes out of our taps? Why do we no have clear data that tells just how much water data centres use? And why are so many data centres being built in areas which are already water stressed?  Join Caroline Lucas and Ollie Hayes as they all of these questions and more.  ⁠⁠Read the redacted Joint Intelligence Committee Report here⁠⁠ ⁠⁠Find out more about the National Emergency Briefing here.⁠⁠ Find Sandra Postel's book here Read Global Action Plan's AI Data Centre Water Report Here Producer: India Dunkley Video Editor: Kieron Leslie Social Producer: Celine Charles General Manager: Tom Whiter Learn more about your ad choices. Visit podcastchoices.com/adchoices

Millions of us have flocked to the cinema to see fantastical portrayals of civilizations fighting over water. Whether it's James Bond in Quantum of Solis or the battle to hoard moisture on the desert planet of Aricus in Dune or the warring factions in Mad Max Fury Road, writers know that when humanity's most precious resource is in short supply, conflict and antagonism follow. But is a post-apocalyptic vision from science fiction, about to become reality. Well, according to the UN, the world has just entered the era of what they call global water bankruptcy. Water systems relied on by six billion people and half of the world's food production are being pushed beyond the point of recovery.

Now, this marks the first time that scientists have declared water systems bankrupt rather than stressed or in crisis. Put plainly, this means irrelevously. reversible damage to natural water systems. And that constitutes not just a humanitarian crisis with the impacts falling disproportionately on those who can least afford it. It's a geopolitical one too. But the good news is experts already know what we can do about it. Welcome back to when nature becomes a security threat with me, Caroline Lucas.

In the first two episodes of this series, we looked at the report the government didn't want us to written by the UK's top intelligence chiefs, and which warns that climate and nature collapse pose a serious national security threat to this country. And today, we turn to the resource at the heart of all of it, water. Water scarcity is often called a threat multiplier. And right now it's contributing to food insecurity, it's deepening economic crises, exacerbating social and geopolitical tensions, and potentially fueling conflict.

So in this episode, we'll be asking, when does a drought stop being a humanitarian crisis and start being a security threat? Could we really go to war over water? And is the AI race about to make our water crisis even worse? For the UK, the real danger isn't just a tap running dry at home. It's systemic. As we heard last week, the UK leans heavily on climate vulnerable nations to keep us fed. so when water crises hit overseas, the shockwaves reach our supermarket shelves. That's precisely the kind of cascading risk flagged in the second suppressed government report

that we've discussed on this series, this time from the Department for Environment, Food and Rural Affairs, Depra, on the UK's critical systems. It reveals that water scarcity isn't some distant threat. It's already here. 15% of our surface water and 27% of our groundwater aquifers are being drained faster than nature can refill them. And that, of course, will only be exacerbated by new water-intensive industries, like the spread of data centres to feed the booming growth of AI. Now, those data centres depend not only on vast amounts of reliable electricity,

but also on large volumes of water, both to keep their servers cool and indirectly through electricity generation to power them. Yet global water demand how much we need is currently expected to exceed supply, how much we have, by up to 40% by 2030. So I wanted to ask a question that sounds almost dystopian. Could we reach a point where water is prioritised for cooling servers over supplying people's drinking water?

I put that to OLLY Hayes from Global Action Plan UK, who's campaigning to force AI companies to disclose exactly how much water their operations really consume. So, Ollie, there seems to be a huge amount of controversy, just about some of the basic facts about how much water these AI data centers really need. So you've got some people saying that the demands have been massively overstated. You've got other people saying they're really underestimated. So why is it so difficult to get accurate data on this?

Yeah, it is difficult to get accurate data. And partly that's because there is very little transparency from the industry itself. There are no requirements for data center developers or operators to disclose how much water they're using. And even the water companies themselves, some of them claim that they don't know how much water they're supplying to data centers. So we have very poor data. But we do have some good quality research that looks at and tries to estimate the amount of water that the data centers are using. And we know that just a mid-sized AI data center will use about as much water as roughly 10,000 people would use. So, you know, a mid-sized town or a small town.

And obviously what we're seeing is the proliferation of data centers both in size but also a huge growth in net. scale and that inevitably puts water use up. And I guess the picture is really affected by the fact of where these data centers actually are. And I was reading one of your reports, I think, that around 84% of proposed sites are in areas that are projected to be water stress by 2040. And so is that the reason that some of these estimates come up with a very low figure for the amount nationally that data centers are using in terms of water? Because in fact, Once you average it out across the whole country, yes, the figure might look very small.

But in actual fact, quite a lot of these data centres are concentrated in water stressed areas. 100%. Yes. It matters hugely where the data centres are and where they're taking water from. And we are seeing in this country a massive concentration of existing and planned data centres in the southeast of England, which, as we know, is the driest part of the country and is severely water stressed, particularly at the moment. times of heat waves. So adding this new novel demand to water supply in these places creates a really acute problem. And as you say, I mean, the industry and its lobbyists like to paint a very different picture. They like to say, well, hang on, per query on chat GBT, it's just a fraction of a teaspoon. Or once you average it out over the course of the entire country's use, you know,

it's really not that much, but that's a slightly disingenuous way of looking at it. Yeah. I do find it shocking that, as you say, that we don't even know, or even some of these water companies themselves don't know how much the data centers are using. Why isn't their legislation? I understand in the EU, for example, they are bringing in requirements that data centers should report, for example, their freshwater consumption. I mean, there's very poor rules and regulations around data center growth generally. We are at Global Action Plan with our partners at Foxglove recently challenged the government's decision to approve a data center because there was no environmental impact assessment

in that planning application. It was deemed that one wouldn't be necessary. And this is despite the fact that they are demanding enormous amounts of power. Where's that power going to come from? inevitably, some of it is going to come from fossil fuel generation, which is going to push up emissions, and they're demanding a lot of water to cool them. So it's pretty shocking, really, how lethal there is in terms of conditions placed on data centres, and we're pushing very hard for those conditions to start to come into effect, and for them to be imposed nationally,

because that's the other thing which is happening, is that these data centers are being looked at on a case-by-case basis, but actually it's the key-by-case basis, but actually it's the cumulative effect, which starts to get really worrying. And as we are seeing, you know, they are being planned and started to be built in very, very large numbers. And the facilities themselves are orders of magnitude bigger than anything we've got at the moment. So the impact is inevitably increasing, but there's very little consideration of it. And one of the factors in all of this that I hadn't fully appreciated was that when the government designated AI data centers as national critical infrastructure back in 2024, that essentially means, doesn't it, that water

companies are now legally unable to disconnect to, for example, AI data centers, even at times of real water stress. And so, in a sense, those data centers are going to be taking water, potentially before ordinary householders, for example? Absolutely. I found this genuinely shocking when I realized this was going on. You're absolutely right. The designation of data centers as critical national infrastructure gives them lots of protections in the way that a nuclear power station or certain security infrastructure will be given these protections. But one of the things included in those protections is essentially being insulated from any

water company demands to stop using water. So in times of drought or in times of water scarcity, the water company can in theory at the moment, say to an industrial user, we need to scale back your supply or we need to turn it off altogether. But if data centers are designated as critical national infrastructure, they can't. They can't turn it off. And we know we've done lots of polling of people's attitudes towards data centers and their sense of where they should sit in the priority of many other industries when it comes to scarce resources. And surprise, surprise, they come at the bottom of the pile. people think farming is more important.

They think the NHS is more important. They think household use is more important. No one thinks that data centers are worthy of protection in this way. And I think that's going to become a bigger and bigger political problem. Because, of course, data centers need most water and most calling when it's hottest and when the rest of us need most water. Yeah, exactly. And I was struck about the irony of the government just very recently launching a new, I think it's a 75 million pound publicity campaign to try to persuade the public to use less water.

And so you've got this kind of situation where we are all being urged to take shorter showers essentially so that AI data centers can go on guzzling as much water as they like. I found this mind-blowing, I have to say. And it comes hot on the heels of, I think, about 12 months ago, the government asking us all to consider our email use as a way to conserve water as well. Irony is alive. Exactly. It would be funny.

It is quite funny, but it would be funnier if it wasn't, you know, also quite serious. You know, we have already an acute problem with water in this country, which is that we are looking at a 5 billion liter shortfall per day in a couple of decades. And those figures are arrived at before even considering data center use. So this is just projections based on, you know, the growing population, our existing industries, growing demand, et cetera, and the changing climate. So this massive additional demand really, really needs factoring in to begin with. And then there need to be constraints put on the industry. And that's just the opposite of what we're seeing from the government. They think they're going to contribute to a lot of growth. And in that sense, they are saying, let's get out of the

way. Let's let them do whatever they want. But that is just not responsible. And what about technological advances? To what extent is it the case that that if we were being a little bit stricter about the kinds of water that they're using, for example, using wastewater or using closed loop systems where they're using less water, how much difference can those technological changes actually make? They can make a difference. And we absolutely should get to a point quickly, I think, where the government must insist that they use the least water-intensive cooling process is possible.

Now, data centres often don't want to do that, because if, for instance, they're using air conditioning or the equivalent of air conditioning to cool their servers, well, that means that there is a significant proportion of their power supply, which they can't use to power the servers. And so, you know, their clients get less bang for their buck. And also power is more expensive than water. So there are big economic incentives for the data centers to continue using evaporative water cooling rather than less intensive methods, whatever they say.

But, and this is, I think, the most important point, even if they get to a stage where they genuinely aren't using any water for cooling on site, at least three quarters of their water footprint, and some studies say it's more than that, pushing 90%, comes from the generation of the electricity they need to power their operations. So using a lot of water, heating it up, using fossil fuels to turn it to steam in a gas power electricity generating station. That is where the bulk of it comes. And that is why what is absolutely insistent, what should be insistent is that data centers are only powered by renewables. One, because that is what is required on a power front. Absolutely, we can't have data centers

using gas. And we can talk about that a bit more if you like because they are and they want to. But two, that is the key to reducing the water footprint dramatically. And just the last sort of reflection in a way, do you think that environmental breakdown itself could become a kind of overlooked constraint on the technological growth here? So for people who are sort of very gung-ho about wanting to see the expansion of AI and the data centres and they want the UK to be at the forefront of this race, do you think it would be fair to say that they are just simply not factoring in the world? themselves the environmental constraints that we have and therefore from their own perspective

they should be thinking much more about water use, energy use and so forth and taking on board some of the kinds of measures that you're talking about. Oh, I absolutely do. I absolutely do. The industry began its kind of PR blitz a couple of years ago by saying that this was completely consistent with environmental goals. You know, that this is, we could accommodate this growth within attempts to reduce fossil fuel use and cut pollution.

They've changed their tune quite quickly. First, they were saying it doesn't really use much energy. Then they were saying, oh, well, actually, we can just power at always renewables, which we can't, by the way, there's too much. And now they're saying right out on the open, well, it's climate goals or it's AI. You've got to choose. So they're being unbelievably sort of brazen about the fact that they don't care about climate goals.

The big tech companies who are behind these data centers, ultimate operators of most of the big ones, they've all abandoned their climate commitments because they can't stick to them because of the emissions associated with their data centers. So, you know, it was probably greenwash to begin with, but it's now out in the open that, you know, they are pursuing a very different goal. And I think the final point on this is I think the government has a problem here because they have a stated intention to, clean up the power sector, get pollution out of power generation by 2030, which is incredibly ambitious anyway, but necessary. And they also have an intention to massively expand the AI industry. And those two things are on a collision course. They just are. There is so much more that I'm going to be covering in this series. We're going to be looking at food security and about the myths, really, behind the headlines to do with climate migration.

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