alt Hacker NewsThese are more like HPC supercomputers than garden variety datacenters. That's why there's so much concern re: water use for the electricity being supplied. (That's easy to address in principle, of course: wind and solar power use up negligible amounts of water compared to other sources.)
Most of the water concern is evaporative cooling of the datacenter itself. But IMO not too much of a concern. The energy use and the resource use to make the chips, etc, is bigger.