Right on, Steve! But all our "planning" departments and politicos keep approving more and more housing with not a pause to consider environmental and infrastructure improvements. Land owners and developers rule! Not to mention the latters' generous campaign contributions to the former. There is no logic in any of this: Sunny Southern is a desert that used to bloom in some places when the rivers flowed. Farmers got them dammed. Now we're damned!

So Cal is, indeed, a desert...with some swamp and marsh land. We need to take a hint from other countries that are also deserts.
We need to build desalination plants for Ventura County. They will provide all the potable water we could use. And, they would pay for themselves in 5 to 10 years. Use water reclamation plants for the landscapping and irrigation needs. Then, we won't need water from the Colorado (becoming briny) River or the Sierra (ever decreasing) snowpacks.

Most of Southern California is not a desert. Scientists call it a semi-arid zone, and the distinction between semi-arid (our landscape in Ventura County, where rainfall can average as much as 24 inches a year in Upper Ojai) and a true desert will be apparent to anyone who drives out to Palm Springs.

That said, it's true that global warming will mean a greater likelihood of drought. But before we panic and start building huge and expensive industrial solutions, we should ask ourselves how we want to live on this land. For example, a hundred years ago most farmers in Ojai did just fine with stone fruit crops (such as apricots) and no irrigation. Citrus for a long time was lucrative, but now with global markets producing so many oranges and lemons, and the cost of water rising rapidly in our region, it may not make economic sense. Perhaps we would be better off trying to think of ways to help our farmers adapt to changing water conditions, then spending hundreds of millions of dollars to preserve a habitual way of life.