Phoenix and most of its suburbs have become really good at using a lot less water even as their populations boomed, according to Sarah Porter, director of the Kyl Center for Water Policy at Arizona State University. "We have largely decoupled urban growth from an increase in water demand," Porter says.

Arizona State University water researcher Kathleen Ferris had called for the groundwater report’s release, and on Tuesday said she was delighted that Hobbs made it public. “It’s a hugely important step,” Ferris said. “As the governor said, it’s about transparency and knowledge. We should not be allowing this growth to occur when the water isn’t there.”