They can have water brought in. It may end up costing more than gasoline though. I have a friend who lives in the Owens Valley, and he has his water trucked in.

Also, no one mentioned all the development in Utah. They take the river water closer to the source. All kinds of new golf courses and stuff like that.

I warned my friends in Cali and Vegas about this exact scenario fifteen years ago. Now I have a river in my back yard.