Canada

I guess that makes sense but how much water does they actually use?

I get why this is problematic in much of the US, but I don’t know why we can’t build data centres in northern Ontario and Quebec. 

In general I agree it's overblown, but as far as closed loop cooling, that's a misdirection. Even the so-called closed loop systems usually rely on a secondary cooling loop with evaporative cooling towers that cool the primary closed loop. While it is an improvement that they aren't just treating the primary coolant as single-use and dumping it after it's heated, the inclusion of the secondary cooling loop means it does not eliminate water usage. Basically, in the secondary (open) loop they continuously flow water onto the radiators, typically using large arrays of cross-flow cooling towers like this until the combination of heat and forced airflow turns the water into vapor and that phase change sucks the heat out much faster than airflow alone would allow. But the water becomes vapor and has been blown away, so you need to add more water continuously. True "dry cooling" implementations do exist using only air cooling and direct heat exchange in the final stage, but they are rare and very much the exception, not the norm, especially in the southern US where most of the data centers are being built. If the air is cool enough on its own, or your heat load is low enough, you can get away without evaporating any water, but most of the time especially in the hot climate of the south, you'll need that water to satisfy the cooling demands, and quite a lot of it.

Granted, I don't think the water usage is as big a problem as people make it out to be, water is something we can create sustainably and straightforwardly when we have enough energy, and at the end of the day it boils down to just being another form of the massive energy problem created by these new facilities being foisted upon us at a time when we are already desperately struggling to make sufficient energy and meet our energy demands in an environmentally friendly way. Meanwhile, fossil fuels will "helpfully" fill those needs effortlessly, undoing all the hard work we've done and the progress we've made and of course making certain people and countries a lot more money.