The term "water consumption" makes people think the water is destroyed, which is probably a large part of the controversy.
Where do you think the evaporated water goes?
- There's an entirely different legal framework around how water from rivers is allocated. The "normal" flow of the most important river, the Colorado River, was calculated during a time of unusually high flow, so there's a lot of tension between different states about whether they're getting their fair share.
- To give you a sense of how "thirsty" the west is, the Colorado River rarely reaches the ocean anymore.
- groundwater use is generally much less regulated, which is causing issues like the Oglala aquifer to drop at an alarming rate. Many aquifers are damaged if they're overpumped, because the weight of the ground above them will crush empty spaces.
- bad actors in the groundwater space can lower the water table and make other peoples' wells run dry
- this is made more complicated by the fact that surface water and ground water interact with each other. Reducing stream flow can affect groundwater, and using groundwater can affect streamflow.
If you want an approachable and entertaining introduction to some western water issues (including the backstabbing and plotting that inspired Chinatown!), I'd suggest reading Cadillac Desert by Marc Reisner.
In recent news: https://www.texasmonthly.com/news-politics/jacobs-well-texas...
Also: this DID end up turning into a multi paragraph lecture. My bad.
Drinking water, spraying it on crops, using it to clean a car, or using it to flush a toilet all end up with the water evaporating, or making its way to the ocean and evaporating from there.
Ultimately, if a river provides a certain number of acre-feet of fresh water, evaporating it to cool a data centre uses it just as much as to evaporating it to grow alfalfa in a desert, except perhaps more usefully.
We do get new fresh water at a reasonable pace thanks to rain - but in many parts of the world we are using it faster than that, and not just depleting the stored volume of fresh water but destroying the storage "containers" themselves.