Ok, its maybe more expensive than I realised according to that source, but I would argue that comparing it to something like charging EVs or running a fridge is not a fair comparison. If you desalinate 1000 litres of water it's not the same as a household using 1000 litres of water. Not exactly. Once water is in a municipal system it's cleaned and reused many many times. Desalination could overcome water shortages by topping up water in a system, in times of drought, rather than just waiting for rain.
Hm, the only reuse of municipal water I know is using treated sewer water for watering plants. I don't think any US cities recycle water back into a potable water system -- have you heard of that happening anywhere?
(I don't remember how this relates to the original argument)
Edit: oh if you meant "data center" by "municipal" then I guess! I thought you meant city drinking water
Ok I had heard of it happening in the UK but now I can't find any evidence of such, apart from a just approved scheme to treat wastewater and pump it into the Thames upstream, which is then used to source drinking water in London. So in a way, its going to happen in London, even if it hadn't already been, as I had believed.
But I would hope datacentres could use recycled or desalinated water for cooling rather than using drinking water.