Most data centers are closed-loop, like your air conditioner. Does your air conditioner use water?

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.