World's population is growing quickly, and we're not only talking about adding more people, we're talking about more people with better lives.
Agriculture faces a big challenge, it has to produce food to feed 9 billion people by 2050. Experts say that there will be no enough resources to provide food for our population. Moreover, some aquifers under the surface are going down the drain.
Farmers can't grow corn without irrigation, or it wouldn't be the kind of irrigation production that they're used to using. While dryland corn averages 24 bushels an acre, irrigated corn averages 200 bushels an acre. So the risk with dryland is important. The loss of irrigation would mean less income, fewer business, a decline in land values...
The answer is not shutting off every center pivot. Farms and irrigation communities will never accept to stop watering with machines that make their local agricultural production be sustainable.