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From https://www.newyorker.com/magazine/2025/11/03/inside-the-dat...

> I asked the farmer if he had noticed any environmental effects from living next to the data centers. The impact on the water supply, he told me, was negligible. "Honestly, we probably use more water than they do," he said. (Training a state-of-the-art A.I. requires less water than is used on a square mile of farmland in a year.) Power is a different story: the farmer said that the local utility was set to hike rates for the third time in three years, with the most recent proposed hike being in the double digits.

The water issue really is a distraction which harms the credibility of people who lean on it. There are plenty of credible reasons to criticize data enters, use those instead!



The other reason water usage is a bad thing to focus on is that datacenters don't inherently have to use water. It's not like servers have a spigot where you pour water in and it gets consumed.

Water is used in modern datacenters for evaporative cooling, and the reason it's used is to save energy -- it's typically around 10% more energy efficient overall than normal air conditioning. These datacenters often have a PUE of under 1.1, meaning they're over 90% efficient at using power for compute, and evaporative cooling is one of the reasons they're able to achieve such high efficiency.

If governments wanted to, they could mandate that datacenters use air conditioning instead of evaporative cooling, and water usage would drop to near zero (just enough for the restrooms, watering the plants, etc). But nobody would ever seriously suggest doing this because it would be using more of a valuable resource (electricity / CO2 emissions) to save a small amount of a cheap and relatively plentiful resource (water).


> The water issue really is a distraction which harms the credibility of people who lean on it

Is that really the case? - "Data Centers and Water Consumption" - https://www.eesi.org/articles/view/data-centers-and-water-co...

"...Large data centers can consume up to 5 million gallons per day, equivalent to the water use of a town populated by 10,000 to 50,000 people..."

"I Was Wrong About Data Center Water Consumption" - https://www.construction-physics.com/p/i-was-wrong-about-dat...

"...So to wrap up, I misread the Berkeley Report and significantly underestimated US data center water consumption. If you simply take the Berkeley estimates directly, you get around 628 million gallons of water consumption per day for data centers, much higher than the 66-67 million gallons per day I originally stated..."


Also from that article:

> U.S. data centers consume 449 million gallons of water per day and 163.7 billion gallons annually (as of 2021).

Sounds bad! Now let's compare that to agriculture.

USGS 2015 report: https://pubs.usgs.gov/fs/2018/3035/fs20183035.pdf has irrigation at 118 billion gallons per day - that's 43,070 billion gallons per year.

163.7 billion / 43,070 billion * 100 = 0.38 - less than half a percentage point.

It's very easy to present water numbers in a way that looks bad until you start comparing them thoughtfully.

I think comparing data center water usage to domestic water usage by people living in towns is actually quite misleading. UPDATE: I may be wrong about this, see following comment: https://news.ycombinator.com/item?id=45926469#45927945


Agriculture feeds people, Simon.

It's fair to be critical of how the ag industry uses that water, but a significant fraction of that activity is effectively essential.

If you're going to minimize people's concern like this, at least compare it to discretionary uses we could ~live without.

The data's about 20 years old, but for example https://www.usga.org/content/dam/usga/pdf/Water%20Resource%2... suggests we were using over 2b gallons a day to water golf courses.


The vast majority of water in agriculture goes to satisfy our taste buds, not nourish our bodies. Feed crops like alalfa consume huge amounts of water in the desert southwest but the desert climate makes it a great place to grow and people have an insatiable demand for cattle products.

We could feed the world with far less water consumption if we opted not to eat meat. Instead, we let people make purchasing decisions for themselves. I'm not sure why we should take a different approach when making decisions about compute.


> We could feed the world with far less water consumption if we opted not to eat meat.

If you look at the data for animals, that’s not really true. See [1] especially page 22 but the short of it is that the vast majority of water used for animals is “green water” used for animal feed - that’s rainwater that isn’t captured but goes into the soil. Most of the plants used for animal feed don’t use irrigation agriculture so we’d be saving very little on water consumption if we cut out all animal products [2]. Our water consumption would even get a lot worse because we’d have to replace that protein with tons of irrigated farmland and we’d lose the productivity of essentially all the pastureland that is too marginal to grow anything on (50% of US farmland, 66% globally).

Animal husbandry has been such a successful strategy on a planetary scale because it’s an efficient use of marginal resources no matter how wealthy or industrialized you are. Replacing all those calories with plants that people want to actually eat is going to take more resources, not less, especially when you’re talking about turning pastureland into productive agricultural land.

[1] https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1...

[2] a lot of feed is also distiller’s grains used for ethanol first before feeding them to animals, so we’d wouldn’t even cut out most of that


That paper makes the opposite argument than you thought it made. Even from a freshwater perspective it’s more water-efficient to get calories/protein/fat directly from crops than from animal products.

Since you like their work, the authors of your paper answered that question more generally here https://link.springer.com/article/10.1007/s10021-011-9517-8 where they conclude "The water footprint of any animal product is larger than the water footprint of crop products with equivalent nutritional value".

You make some often debunked claims, like we'd have to plant more crops to feed humans directly if we stopped eating meat.

This shouldn't make intuitive sense to you since animals eat feed grown on good cropland (98% of the water footprint of animal ag) that we could eat directly, and we lose 95% of the calories when we route crops through animals.


You’re confusing my argument. I’m not arguing that meat is more efficient than plants; that by itself is obviously untrue because of the trophic efficiency loss. I’m arguing that meat uses marginal resources that would otherwise be useless for growing food. If we eliminate meat we’d eliminate a lot of marginally productive farmland that is naturally irrigated and have to replace it with industrialized irrigation farming that will be significantly more expensive and use more water and energy. Maybe if we had a global cultural reset with industrialized farming, but no one is going to be happy replacing their beef and chicken with the corn and barley and hay that those lands normally grow, much of it inedible to humans.

That paper isn’t actually debunking anything that I’m saying. If the water foot print per calorie is 20x for beef but the feed is grown with 90% of its water from rainfall, that’s not a 20x bigger footprint in a way that practically matters because most of that water is unrecoverable anyway. The water that is recoverable just makes it through the watershed.

Meat is a way to convert land that cant grow things people can or want to eat into things that people will eat. That pastureland and marginal cropland growing animal feed can’t just be converted to grow more economically productive crops like fruit and vegetables without Herculean engineering effort and tons of water and fertilizer. Instead the farming would have to stress other fertile ecosystems like the Southwest which would make the water problems worse, even if their total “footprint” is smaller. The headline that beef uses 20x more water per calorie completely ignores where that water comes from and how useful it actually is to us.

I don’t doubt that we can switch to an all plant diet as a species but people vastly underestimate the ecological and societal cost to do so.


I mean it's even simpler. Almonds are entirely non essential (many other more water efficient nuts) to the food supply and in California consume more water than the entire industrial sector, and a bit more than all residential usage (~5 million acre-feet of water).

Add a datacenter tax of 3x to water sold to datacenters and use it to improve water infrastructure all around. Water is absolutely a non-issue medium term, and is only a short term issue because we've forgotten how to modestly grow infrastructure in response to rapid changes in demand.


Thanks for the sanity!! I wish more people understood this


Ask people which they'd rather have: -no more meat and a little better AI -keep their meat and AI doesn't improve from where it is today..


I called out golf in my first comment in this thread.

If data center usage meant we didn't have enough water for agriculture I would shout that from the rooftops.


Yep--I'm agreeing that one's a good comparison to elaborate on.

Exploring how it stacks up against an essential use probably won't persuade people who perceive it as wasteful.


Growing almonds is just as essential as building an AI. Eating beef at the rate americans do is not essential. Thats where basically all the water usage is going.


Agriculture is generally essential but that doesn't mean that any specific thing done in the name of agriculture is essential.

If Americans cut their meat consumption by 10%, we would use a lot less water in agriculture and probably also live longer in general


Iran's ongoing water crisis is an example. One cause of it is unnecessary water-intensive crops that they could have imported or done without (just consume substitutes).

It's a common reasoning error to bundle up many heterogeneous things into a single label ("agriculture!") and then assign value to the label itself.


I am surprised by your analytical mistake of comparing irrigation water with data-center water usage...

They are not equivalent. Data centers primarily consume potable water, whereas irrigation uses non-potable or agricultural-grade water. Mixing the two leads to misleading conclusions on the impact.


That's a really good point - you're right, comparing data center usage to potable water usage by towns is a different and more valid comparison than comparing with water for irrigation.


They made a good point, but keep in mind that they're doing a "rules for thee, not for me" sometimes.

The same person who mentioned potable water being an important distinction also cited a report on data center water consumption that did not make the distinction (where the 628M number came from).


The problem is many data centers are in areas where water systems are supply constrained... - https://spectrum.ieee.org/ai-water-usage


This is not a distinction that your second link (that has the 628M number) was making either

> water evaporation from hydroelectric dam reservoirs in their water use calculations


The factual soundness of my argument is independent of the report quality :-) the report influences comprehension, not correctness...

The fact data centers are already having a major impact on the public water supply systems is known, by the decisions some local governments are forced to do, if you care to investigate...

https://spectrum.ieee.org/ai-water-usage

"...in some regions where data centers are concentrated—and especially in regions already facing shortages—the strain on local water systems can be significant. Bloomberg News reports that about two-thirds of U.S. data centers built since 2022 are in high water-stress areas.

In Newton County, Georgia, some proposed data centers have reportedly requested more water per day than the entire county uses daily. Officials there now face tough choices: reject new projects, require alternative water-efficient cooling systems, invest in costly infrastructure upgrades, or risk imposing water rationing on residents...."

https://www.bloomberg.com/graphics/2025-ai-impacts-data-cent...


What counts as data center water consumption here? There are many ways to arguably come up with a number.

Does it count water use for cooling only, or does it include use for the infrastructure that keeps it running (power generation, maintenance, staff use, etc.)

Is this water evaporated? Or moved from A to B and raised a few degrees.


This is the real point. Just measuring the amount of water involved makes no sense. Taking 100 liters of water from a river to cool a plant and dumping them back in a river a few degrees warmer is different from taking 100 liters from a fossil acquifer to evaporatively cool the same plant.


Humans don’t consume much water used by humans. Cows do.


A farmer is a valuable perspective but imagine asking a lumberjack about the ecological effects of deforestation, he might know more about it than an average Joe, but there's probably better people to ask for expertise?

> Honestly, we probably use more water than they do

This kind of proves my point, regardless of the actual truth in this regard, it's a terrible argument to make: availability of water starts to become a huge problem in a growing amount of places, and this statement implies the water usage of something, that in basic principle doesn't need water at all, uses comparable amount of water as farming, which strictly relies on water.


The author of the article followed the quote from the farmer with a fact-checked (this is the New Yorker) note about water usage for AI training.




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