PHOENIX (AP) — Arizona will not approve new housing construction on the fast-growing edges of metro Phoenix that rely on groundwater thanks to years of overuse and a multi-decade drought that is sapping its water supply.

In a news conference Thursday, Gov. Katie Hobbs announced the pause on new construction that would affect some of the fastest-growing areas of the nation's fifth-largest city.

Driving the state's decision was a projection that showed that over the next 100 years, demand for almost 5 million acre-feet of groundwater in metro Phoenix would be unmet without further action, Hobbs said. An acre-foot of water is roughly enough for two to three U.S. households per year.

Officials said the move would not affect existing homeowners who already have assured water supplies.

Despite the move, the governor said the state isn’t running out of water. “Nobody who has water is going to lose their water,” Hobbs said.

Years of drought in the West worsened by climate change have ratcheted up pressure on Western states to use less water. The drought has also made groundwater — long used by farmers and rural residents in Arizona and elsewhere with little restriction — even more vital.

Until today's announcement, that was the case for developers in Phoenix suburbs like Queen Creek and Buckeye, said Nicole Klobas, chief counsel for the Arizona Department of Water Resources. Builders relied on the region's groundwater to show that they had adequate water supplies for the next 100 years, which Arizona requires for building permits.