Comment by simonw
6 months ago
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://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.
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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.
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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.