Don't say I didn't warn you...
Much like guns, the water usage problem in California could benefit from an overall culture shift. Without the shift in thinking that watering your lawn (or having a lawn) is a measurement of prestige, we're going to keep running out of water.
Here's a link to some of the data at the California Department of Water Resources.
Some Californians have responded, however. A drop in some regions of 10% of water usage during this time of drought. http://www.latimes.com/local/lanow/la-me-ln-california-drought-water-20141007-story.html