If California had a functional government, seasonal drought wouldn't be an issue. https://www.gov.il/en/departments/general/project-water-desa...
"In order to comply with the desalination plan set out by the cabinet, 5 desalination plants were constructed over the years, in Ashkelon (2005), Palmachim (2007), Hadera (2009), Sorek (2013) and Ashdod (2015), with total production capabilities of some 585 million m3."
The problem is price. From the wiki[1]:
> "The cost of water from the plant will be $100 to $200 more per acre-foot than recycled water (approximately 0.045 cents per gallon), $1,000 to $1,100 more than reservoir water (approx. 0.32 cents per gallon), but $100 to $200 less than importing water from outside the county. As of April 2015, San Diego County imported 90% of its water."
Considering SD imports so much water, this is a big win. But still, this one plant cost nearly $1b to complete, and only provides 7% of the potable water for San Diego County. It's a non-trivial cost to use Desal water vs recycling efforts and loss prevention from reservoirs.
Edit: 1- https://en.wikipedia.org/wiki/Claude_%22Bud%22_Lewis_Carlsba... 2- https://www.nytimes.com/2021/10/29/us/san-diego-drinking-wat...
San Diego City budget is $5 billion: https://www.sandiego.gov/sites/default/files/fy23ab_v1execut...
San Diego County budget is $7 billion: https://www.sandiegocounty.gov/content/sdc/openbudget/en/hom...
This seems that if they needed to they could do it.
For inland california, this isn't the case since pumping costs don't make it so clear cut cost wise. Reclamation efforts like the OP company, are a really big deal because they are one of those rare "easy-wins".
If San Diego needed to then they probably could, but this is generally one of the most expensive options. It is politically impossible, but it would probably be cheaper to pump water from the Klamath to San Diego than to extract it via desalinization.
It cites a hit piece from Fox News Radio with equally confusing numbers.
Anyway, the Fox article says it will cost $1000-1400 (or maybe $1500 because they inflate the number as they go) per acre foot. At $1500, that's 0.46 cents per gallon, which is about 10-15x more than people currently pay to flood irrigate fields. Flood irrigation is notoriously wasteful.
Anyway, tap water costs about 1 cent per gallon in San Jose. These desalination plants could affordably provide water for residential use.
Parts of California produce more solar power than can be used at that time during parts of the day - could that extra electricity be used for desalination?