Aguanomics has an interesting post on desalination today. The guys at DXV claim they can produce desalted water at a little more than $600 per acre foot, about half the cost estimates of current technology. They may be overly optimistic, but this future cost estimate for desalination is less crazy than the PPIC assuming >$2000 acre foot for desalination (in 2050 in current dollars) in their pro-peripheral canal report.
It's a good time to link to the $10,000 bet I offerred to the PPIC/UC-Davis authors months ago. If PPIC/UC-Davis decides to stand behind their assumpitions and accept the wager, I pledge my winnings to DXV or whomever breaks the $1000 barrier.
Desalination isn't the silver bullet for California's water problems. However, as the backstop long-run technology for urban areas, it is highly relevant to decisions of whether to spend billions on a peripheral canal and more dams.