Even the U.S. Government Says AI Requires Massive Amounts of Water

https://dgtlinfra.com/data-center-water-usage/

I found that article really informative, TLDR: a lot of water is recycled and recirculated yes but not all. Also they sometimes evaporate water for cooling, and eventually the water does need replaced. I think the concerns were mostly scale and water increasing in conductivity over time.

It's not a sealed system like a personal computer uses. They're on a huge huge scale. They use evaporation / cooling towers. But those lose a certain amount of water to evaporation which needs to be replaced regularly.

I work on chillers and if the cooling towers float valve isn’t adjusted right and it’s constantly pushing water out for a year without someone catching it, you would loose potentially 500,000 gallons a year or more, and that’s just one part. Granted it goes back into the city’s system but that’s our clean water that has to go into a treatment system taking time and resources. Every place is different but here in Arizona I would assume they use a similar commercial setup. The water to the building from the plant is a closed loop but that’s harder for the cooling towers to the chillers since it’s evaporative, which you don’t loose a lot of water but that’s assuming that everything is in working order and well maintained, and a lot of commercial facilities are cheap on maintenance and don’t like to fix things until it becomes a big issue. To be fair I think industrial only takes up 6% of water use but it’s still precious here.

They can! We've got a nuclear power plant that evaporates water from sewage for cooling.

https://en.wikipedia.org/wiki/Palo_Verde_Nuclear_Generating_Station

The Palo Verde Generating Station is a nuclear power plant located near Tonopah, Arizona[5] about 45 miles (72 km) west of downtown Phoenix. Palo Verde generates the most electricity of any power plant in the United States per year, and is the largest power plant by net generation as of 2021.[6] Palo Verde has the third-highest rated capacity of any U.S power plant. It is a critical asset to the Southwest, generating approximately 32 million megawatt-hours annually.

At its location in the Arizona desert, Palo Verde is the only nuclear generating facility in the world that is not located adjacent to a large body of above-ground water. The facility evaporates water from the treated sewage of several nearby municipalities to meet its cooling needs. Up to 26 billion US gallons (~100,000,000 m³) of treated water are evaporated each year.[12][13] This water represents about 25% of the annual overdraft of the Arizona Department of Water Resources Phoenix Active Management Area.[14] At the nuclear plant site, the wastewater is further treated and stored in an 85-acre (34 ha) reservoir and a 45-acre (18 ha) reservoir for use in the plant's wet cooling towers.

If you're location-agnostic as to your datacenter, though, probably easier to just stick a datacenter by the ocean and use seawater, though. Lots of that.

EDIT: Or make use of the waste heat instead of throwing it away. If it's winter and you're a town in Alaska, say, you'd probably just as soon have the heat piped your way.

Also those people..."We need to ban all forms of weather manipulation technology, because space lasers or something something..."

So what you are saying is that if it is permanently cloudy and never sunny anymore in the future it is because of the people who love AI and hate solar power? I could see that happening.