They also have that whack-job Jerry Brown as their Gubaner!
I lived in CA in the early 80’s. There were salt-making plants all along the coast. What they did with the resultant fresh water, I never knew!
Most efficient method of producing freshwater from seawater is done by the flash evaporation method whereby the seawater is heated by combusting natural gas(which we have plenty of). Largest water desalination plants that I am aware of are in Saudi on the Persian Gulf. Desalinated water is pumped through 6-foot concrete pipelines to the larger metropolitan areas hundreds of miles away. The concentrated brine is dumped back into the gulf.