> and the same liquid can be recirculated in a closed loop so no new water is consumed to cool the chips
That doesn't mean a datacenter doesn't have a very high _initial_ need for water, or to replace _some_ amount of leakage, replacement etc (agreed it will be way lower than say a swamp cooler). For example, they could be using millions of gallons as a sort of "ballast" to keep the water temperature very stable in the short run.
This whole projects depends on the whole stack of components to be able to tolerate 45c from memory, drives, the lighting of the building, the humans ...
The entire room wouldn't be 45˚C, or even the entire machine, just the liquid-cooled components.
As long as the water that goes in, doesn’t come out. The inital water requirement is fine. What is problematic in most cases is the warm water containing pollutants is just pumped straight into our local waste water systems or rivers.