Arizona sets limits on construction around Phoenix as groundwater dwindles

Arizona will not allow new housing development in the Phoenix area that depends on groundwater, a decision that comes as the state grapples with a decades-long drought and dwindling water supplies.

Arizona Gov. Katie Hobbs announced the restrictions during a news briefing Thursday that could affect the fast-growing suburbs around Phoenix. The decision by the Arizona Department of Water Resources only applies to groundwater supplies and will not affect current homeowners who already have a secured water source.

The megadrought created the driest two decades in the West in at least 1,200 years, and human-caused climate change helped fuel the conditions. Water sources are dwindling in the western United States, and restrictions on the Colorado River are affecting all sectors of the economy, including construction.

Earlier this year, Arizona predicted that developers planning to build homes in the desert west of Phoenix did not have enough groundwater supplies to fulfill those plans.

A more recent analysis found that approximately 4 percent of the area’s groundwater demand, nearly 4.9 million acre-feet, will not be met over the next 100 years. An acre-foot of water is about what two average households use annually.

The decision will allow developers to continue building in the affected areas, but will require them to find alternatives to groundwater supplies. During a nationwide housing shortage, developers are hoping to build homes in growing metropolitan areas like Phoenix despite water shortages.

Arizona developers said they can deal with dwindling water supplies, pointing to technologies such as low-flow devices, drip irrigation and desert landscaping. The state’s restriction may also prompt developers to seek other sources of water, such as buying access to river water from farmers.

Despite the restriction, the governor said Arizona is not running out of water and is equipped to handle the situation.

“My message to Arizonans is this: We are not out of water and we will not run out of water because, as we have done many times before, we will address the water challenges we face with integrity and transparency,” said Hobbes.

The announcement comes as Arizona experiences a disappearing groundwater table as well as declining levels from the drought-stricken Colorado River, which supplies water to more than 40 million people in the US. The state receives approximately 2.8 million acre-feet annually, or about 18% of the total allocation, from the Colorado River.

Last month, Arizona struck a deal with California and Nevada to voluntarily reduce water use from the river in exchange for federal funding. Arizona has experienced two rounds of mandatory water shutoffs from the river in the past two years.

Correction: A more recent analysis found that roughly 4 percent of the area’s groundwater demand, nearly 4.9 million acre-feet, will not be met over the next 100 years. An earlier version incorrectly specified the time.