Many libertarians and conservatives have been calling for a free market in water in California. I agree that would likely be the best solution overall. However that solution will have inevitable pushback from farmers, who benefit from their existing usage rights. My understanding is that California farmers have a "use it or lose it" right to water resources. In other words, they can use the water or not use it, but they can't re-sell it. This leads to a lot of waste, including absurdities like planting monsoon crops in a semi-arid region. If the farmers could simply resell the water they don't use (at or near the residential water price), there would be more water to go around, and farmers would probably actually come out ahead of the game. While less beneficial overall, it might be politically easier to implement.