Through grant programs, public education and a broad media campaign, foster the growth of fully sustainable farming practices.
With the cost of food unlikely to drop under the present agricultural system, better methods must be adopted to reduce farm overhead, drought impact and distribution costs. The good news is that methods already exist which are easily adapted from present agricultural practices such as aquaponics and bio-intensive farming.
These methods use a lot less water and few if any chemicals. They are scalable and there are already businesses ready to supply the materials and education to make adoption feasible.
A few helpful links: