If you price farmers out of the water market, they will produce less food. Can you imagine what happens when we start having large scale food shortages?
You just don't know about sustainable agriculture and drip irrigation. So, your comment isn't well informed. We won't have a good shortage. The smart farmers will figure a way out.
How do you know whether they know about drip irrigation?
And if they produce less food, prices will rise and they'll have more money to buy more water or Lord forbid make some investments in water sustainability.