Ooh, ooh, I know this one!

First, there are various types of data centers. Not all are water-cooled. Some are only air-cooled. And there are various types of water cooling. The answer also is heavily dependent on climate and type of datacenter. There is no one pat response to a question like this. As is usual with life, the permutations are endlessly complex.

However, these days when people say “data center” they usually mean “AI data center” because that is all they are aware of. And in reality, the concern about water usage (as Noah Smith pointed out) is really displaced anxiety about AI-related job loss. So the water use question already starts out in epistemically-shaky territory.

First, let’s talk baselines. The average 18-hole golf course in Texas uses roughly 275,000 gallons a day of water. You rarely see many complaining about that, right? And that’s a lot. That’s enough water for around 1,000 households. And in another side note, there are about 430 18-hole golf courses in Texas, and about 13,000 in the US total.

The most common data center type now which is an ~100 MW AI aggregate data center uses about 387,000 gallons/day. That is about 1.4x the Southwest golf-course median. Also, a lot of water. I’d argue that this DC is doing something a lot more useful than letting some old dudes hit a little ball around, though. I’ve seen claims that a single AI data center uses as much water per day as large cities, which isn’t remotely true for even the densest, 250 megawatt evaporatively-cooled DCs. These, however, can use about 3.2 million gallons/day. There aren’t many of those facilities, though. Probably around 20-40 in the world only. Houston (as an example) uses around 475 million gallons per day of water.

So, data centers — at least AI data centers — do use quite a lot of water, but the usual reports I see misrepresent this number by 10x to 1,000x. Having the real facts is important. Else you’re just dealing with fantasy, which helps no one.