[rayiner]

A sustainable solution wouldn't involve ending all farming in California. Instead, what you would do is set a tax per gallon that's high enough so that demand for water decreases to the sustainable level of supply. That'll drive a lot of farmers out of business, but that's okay, that's what welfare is for. But some farmers will be able to stay in business because their crops are valuable enough to be worth growing in the desert.

[narrowrail]

As a known lawyer here, you need to appreciate the water law of The West (and all the nuance involved). Unless otherwise over-ruled, it's at a state's discretion issue. IANAL, but I have considerable experience with water in the west; specifically, The Rockies. The oldest water rights are agricultural, so what takes precedence as a matter of law is geared towards that.

Edit: My solution is for the people wanting water rights need to purchase them from those that have them (i.e. the agricultural folks).