https://news.vcu.edu/article/northern-virginia-data-center-a...
Presumably there are some data centers that use water cooling. I think google and amazon's big ones do. But even then, they're not "polluting", they're using them as heat sinks.
There was a lame rolling stone article that claimed amazon was "polluting" in Eastern Oregon, but what Amazon was doing was taking brined water from an aquifer and putting more concentrated brined water back into the water table. Air conditioning doesn't really add brine, so even the premise is ridiculous. I know that article has been referenced a lot by the "Data Centers Pollute The Water" folks.
Secondly drawing brine water from the aquifer to then putting the stronger brine back is essentially water consumption. I would also say it's externalising environmental cost of the stronger brine impact.
Yes, it does. As far as water is concerned, air conditioners are open loop. Air conditioners make water from condensation forming on the inside (cool) coils. Modern window air conditioners then splash that water on the outside hot coils, to benefit from evaporative cooling. I haven't looked into the details about data center water usage, but I would guess the cited usage is from evaporative cooling.