I don't know if it will do the job. Call me skeptical (but not cynical) But the desalination plant going up in Carlsbad is only going to provide 7% of the water needs for the San Diego area. And it's the largest plant being built in the western hemisphere. I'm not sure if desalination is the silver bullet everyone thinks it is.
I'm willing to be convinced. I'm sure we've got some hydrologist Freeper lurking around somewhere :-)
http://www.freerepublic.com/focus/news/3274682/posts?page=14#14
Read this post and the one after it.