Desalination must be insanely expensive; I’m always shocked it wasn’t done decades ago.

Considering California always seems to have power and water issues, I’d think combining these things would make a lot of sense. Some of these exist and there seems to be a fair bit of research in the area. I have to image at some point that will be the direction California would need to go. Of course, if they are all-in on solar and wind, then maybe not.

> Desalination must be insanely expensive

It isn't. Mostly there are environmental concerns.