If past trends in greater Phoenix – agricultural land transitioning to urban – the area is on track to groundwater “safe yield”, according to new research by an Arizona State University team:
Under (business as usual) conditions where population is expected to increase and agricultural activities to gradually decrease, our results indicate a reduction in the use of groundwater of ~23% that, in turn, will likely allow achieving safe-yield. If the decrease in agricultural activities will be less drastic or remain constant in time (i.e., more food will be produced locally), additional water from more energy-intensive water sources (groundwater and CAP) will be needed.
A shift in the trend – less ag land decline – makes it less likely that Phoenix would meet the goal, the researchers found. A shift to more renewables means an even better prognosis for groundwater, given the significant use of water for power plant cooling. And it probably goes without saying that a multi-decadal drought would make things harder.
The paper is Guan, Xin, et al. “A metropolitan scale water management analysis of the food-energy-water nexus.” Science of The Total Environment 701 (2020): 134478. Found behind a paywall here.