No, the solution is to take the idea of free water out behind the barn and executing it. Once the externalities are priced in, you'll see incredibly water inefficient and wasteful crops move to areas that can sustain them, and investment into improving water efficiency.

What you're proposing is the equivalent of wanting someone to lose weight and prescribing exercise, while also allowing them to eat two cheesecakes, four burgers, an entire shifts output of pizza and a handle of liquor a day. You can exercise all you want, they're still getting fat.