There are two competing schools of thought over just how water-intensive AI is. In one, the technology is horribly thirsty. Data centers will exacerbate droughts throughout the country and “drain the great lakes,” as one popular Reddit thread puts it. The former Representative Marjorie Taylor Greene has taken up the issue, sarcastically posting at one point: “How dare the peasants complain about data centers stealing their water and driving the cost of electricity!!”
The other school, populated by Silicon Valley types, holds that “The Data Center Water Crisis Isn’t Real,” as an article in the right-wing publication Pirate Wires argued in December. The issue with water “is totally fake,” “insane,” and has “no connection to reality,” OpenAI CEO Sam Altman said a few months ago.
As with so many debates around AI, the arguments are not always presented in good faith. But unlike, say, the ambiguities over how much work a chatbot can or should be trusted to do, water use seems like it should be measurable, with clear facts supporting one side or the other. That is not the case. Does AI waste a ton of water? Not necessarily. Sometimes. It really depends. “We don’t have the real ground-truth numbers on data-center water use to put everyone on the same page,” Eric Masanet, a sustainability researcher at UC Santa Barbara who studies data centers, told me. Neither data-center operators nor utilities provide much insight; what public information exists can be contextualized, recontextualized, and distorted to suggest basically anything.
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Yet the water issue is tremendously consequential—not only for the well-being of residents in all of the counties where new data centers are popping up but also for the future development and regulation of AI itself. Just this week, when New York Governor Kathy Hochul signed the nation’s first statewide data-center moratorium, her office cited the “massive amounts” of water that hyper-scale data centers could require. In a drought-stricken county or during a heat wave, a data center may seriously burden local water supplies. Where water is abundant and utilities can afford new infrastructure, data centers may pose little issue.
Outside of water-stressed regions, “it’s not really a major concern for now,” Fengqi You, an energy-systems expert at Cornell, told me. “But as the sector grows, who knows?” Turning any particular case into a sweeping pronouncement produces little but heightened emotions and confusion. As ever, the truth is far more nuanced and conditional than activists or tech executives admit.
The problems start with the framing. How much water do data centers use? is not a particularly useful question. On a national scale, these buildings do not use an alarming amount of water. In 2023, data centers used slightly more than 17 billion gallons of water for cooling, as much as about half a million Americans collectively use in a year. This may seem like a lot out of context, but it’s less than a tenth of a percent of the total amount of water used by U.S. farms that year.
Things can look different at the county level. A Meta data-center campus under construction in Lebanon, Indiana, could, at its peak, demand 8 million gallons of water a day: This would be a drop in the bucket in New York City, but it’s more than double the peak demand of the town. Every data center demands a distinct evaluation, and the picture can quickly shift. Water use depends on the local climate, the local water supply, and the makeup of the regional electrical grid, as well as on the design of the actual data center. For Meta’s Indiana data center, city officials have said that planned upgrades mean there is “nothing to indicate” that they will run out of water. Meanwhile, in Newton County, Georgia, a local official has said that “we just don’t have the water” for all of the data centers trying to move in and that the county must “race” to improve local water-recycling facilities.
Rather than worrying about the quantity of water, it’s best to ask how a particular data center uses water. In general, water is always used for the same thing—to keep the computer chips inside these buildings cool—but there are many different methods for doing so. Broadly speaking, data centers can either expel the heat those chips generate with cooling towers, which evaporate water, or with air-cooled chillers or similar technologies that use electricity to vent away hot air. Think of cooling towers as human sweat, which passively cools us down as it evaporates, and chillers as car radiators, which use a chemical coolant and then blow air to physically push out the heat.
The AI industry has settled on the car-radiator approach for many of its biggest, most controversial data centers. They run water directly into the servers to pull away heat, cycle the water down through an air chiller, and then—crucially—reuse it. That’s how OpenAI’s Stargate data center in Texas, Meta’s Hyperion data center in Louisiana, Microsoft’s Fairwater data centers across the country, and many other enormous facilities operate for most of the year. Such closed-loop systems don’t lose water to evaporation, which is likely what Altman was referencing when he called concerns over water “insane”: Once these data centers have water, they don’t need more of it, in theory, because it’s never used up.
The real incentive for closed-loop systems is convenience. Building out local water infrastructure or tapping into a reservoir can take years, using groundwater is controversial (groundwater doesn’t replenish quickly, and using it can pollute the environment), and you can’t realistically bring water from Lake Michigan to your data center in dusty Arizona. Water availability can be a serious bottleneck to new data-center construction. A closed-loop system with air chillers bypasses these problems.
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So why doesn’t every data center just use chillers? For starters, air chillers require substantially more electricity compared with cooling towers to expel the same amount of heat. “Can data centers use zero water? Yes, that’s very easy,” Shaolei Ren, an AI and sustainability researcher at UC Riverside, told me. “But the downside, the cost they have to pay,” is using more electricity—10 to 65 percent more, by various estimates. One nine-gigawatt facility under construction in Utah will, upon completion, require nearly as much power as New York City.
Data centers’ almost surreal power demands are largely being met by combustion turbines, many of which are built by the tech companies themselves (to avoid waiting on upgrades to the local grid). And generating electricity—including from these private power plants, which burn fossil fuels—needs water too. In 2024, Meta’s “indirect” water consumption—referring to the water used during power generation—was 19 billion gallons. That’s 23 times its direct water consumption, and most of it went to data centers.
[From the April 2026 issue: Inside the dirty, dystopian world of AI data centers]
Few industries consistently report indirect water use, in part because many of the estimates are flawed. Indirect use comes from averaging the water footprint of all the power sources on a regional grid—which includes hydroelectric plants that consume huge amounts of water due to evaporation from dams and lakes. In other words, indirect water-consumption figures can arguably under- or overestimate any individual plant’s contributions. Paradoxically, the AI industry’s decision to avoid using water to dissipate heat from inside its data centers might expand some facilities’ overall water footprint. “If you use water to make your cooling more efficient on-site, you will use less electricity,” Jonathan Koomey, a data-center and sustainability researcher, told me. “It’s not a simple matter of water use bad on-site.”
It might be possible to design data centers that use both less electricity and less water. In cooler climates, for instance, data centers can pump in outdoor air; this is what Amazon does at its mega data center in northern Indiana. In summer, spraying small amounts of water into the outside air can bring down the temperature enough to do the same. Data centers are also beginning to experiment with allowing the chips to run at higher temperatures, which reduces the overall cooling demands. And, of course, the rather obvious way to build data centers that put less strain on the environment is to opt for renewables instead of natural-gas turbines.
Until these approaches are the norm, people will understandably worry about the effects these sprawling facilities will have on their communities. Assessing how any data centers will affect nearby reservoirs ultimately requires the scarcest resource of all when it comes to these facilities: accurate and precise information. Tech companies want data centers up and running quickly, so they contract with shell companies that negotiate behind closed doors and under nondisclosure agreements. Residents might find out about new construction only after shovels are in the ground.
Already, rising temperatures and prolonged droughts are out of any individual’s control; now a big industrial facility arrives, under the cover of night, that may or may not exacerbate many problems caused by the climate crisis. This sense of confusion goes a long way toward explaining why data centers’ environmental impacts have become one of the key battlegrounds in the AI backlash—the primary issue, in many cases, is not lack of water so much as lack of control.
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