San Diego is already has a desalination plant and Santa Barbara is about to turn on their own. However, it’s still not enough. Building desalination plants takes a lot of capital and time. Unfortunately, leverage is no longer cheap and the economy is about to suffer a deeper downturn

Also, people especially farmers have been complaining about San Diego’s pricing to pay for their plant. Still, like you I don’t see any other long term solution since CA provides 1/3 of the US food supply. Maybe stop exporting live stock feed grown from the desert (ie water) to Asia?

I know its a bit of a pipe dream, but why not raise taxes and pass a 1930s style infrastructure spending bill to compensate? Would help with the downturn that feels like it'll happen at any point (in earnest, for better or worse) by providing good jobs and solving problems all at the same time?

We could do this with desalination, green energy projects, and other public infrastructure. I'd even love to see us subsidize fiber to homes and businesses en masse and allow ISPs to share the resulting infrastructure like they do in Europe

Desalination doesn’t cost much to build, it costs an absurd amount of money to run at the scale farmers use water.

I was considering cities first with this, which I realize isn't the biggest use of this water but is part of it.

I also imagine with continued investment and research the tech could get better at scale too. It may be hard today but perhaps there's headroom for innovation with more funding while tackling migrating cities to using desalination

A single mid sized farm can use more water than a town of 30,000 people.

What’s affordable for a town is several orders of magnitude different than what’s viable for that farmer.

Raising taxes is not a good idea when many businesses and individuals have already left CA due to high taxes and a high cost of living. That said that also seems to be the only solution to a problem, that's been ignored for decades, which can no longer be ignored. People waited too long to mitigate this problem. Someone can prove me wrong, but there doesn't seem to any good choices left.

I was thinking about federal level infrastructure projects, not just CA per se

Yeah. Something like the federal highway system, or dams.