Arizona has determined that there isn’t enough groundwater for all of the housing construction already approved in the Phoenix area and plans to stop developers from building some new subdivisions, but this is due to overuse. and drought-prone areas in the west and elsewhere are signs of an impending problem. Climate change is straining water supplies.

The state officials’ decision could very well mark the beginning of the end of the explosive growth that has made the Phoenix area the fastest-growing metropolitan area in the country.

Maricopa County, which includes Phoenix and its suburbs, derives more than half of its water supply from groundwater. Most of the rest comes from rivers and waterways, as well as recycled wastewater. As a practical matter, groundwater is a finite resource. It can take thousands of years or more to be replenished.

The groundwater shortage announcement, which the state calls “unmet water demand” for the next 100 years, means Arizona will no longer grant new permits to developers in the Maricopa County area to build well-fed homes. means

Phoenix and its neighboring metropolises must obtain separate permits from state officials every 10 to 15 years for planned developments, and have been denied permits for homes that rely on groundwater in excess of what the state has already permitted. will be

The decision means cities and developers will have to look for alternative water sources to support future development. Many of them face their own water scarcity, for example, buying access to river water from farmers and Native American tribes. The rush to buy water is likely to disrupt the Arizona real estate market, driving home prices higher and threatening the relatively low housing costs that have made the area a draw to people from across the country.

“Housing affordability will be a challenge going forward,” said Spencer Kumps, vice president of legislation for the Central Arizona Association of Home Builders, a trade group. He said commercial buildings, factories and other types of development could continue despite the state’s restrictions on residential construction.

Sarah Porter, director of the Center for Kill Water Policy at Arizona State University, said the change serves as a signal to developers. “We see the end of sprawl on the horizon,” she says.

The state says it has no intention of revoking permits already issued, instead looking to water conservation measures and alternative water sources to produce the water needed for approved projects.

Porter said groundwater shortages won’t derail planned growth in the near term in major cities like Phoenix, Scottsdale and Mesa.

“There is still room for development in designated cities,” Mr. Porter said, referring to cities whose growth plans have already been approved by state water authorities. These cities will no longer be permitted to build anything over that amount.

The new restrictions will be most severe and most immediately impacted in small towns and unincorporated desert areas on the periphery of the Phoenix metropolitan area, where low-cost housing tends to be built. “These are hot spots for growth,” Porter said.

The announcement is the latest example of how climate change is reshaping the American Southwest. 40 million Americans living in Arizona and six other states dependent on the Colorado River, including Phoenix residents who draw water from the Colorado River via an aqueduct, as 23 years of drought and rising temperatures have lowered the water level of the Colorado River. threatening people.

Rising temperatures are increasing evaporation rates from rivers, even though crops need more water to withstand the heat. The amount of water Arizona receives from the Colorado River has already been significantly reduced by voluntary agreements among seven states. Arizona last month agreed to conservation measures that would further reduce supplies.

As a result, Arizona’s water supply is under pressure from both the loss of groundwater and the shrinking of the Colorado River.

And while it assumes that the supply of the Colorado River to Arizona will remain constant for the next 100 years, that uncertainty could make the water scarcity worse than the state’s analysis indicates.

The Phoenix region occupies a valley in southern Arizona, cradled by mountain ridges and cut by the Salt and Gila rivers. The landscape is filled with lush golf courses, baseball diamonds, farms, and swimming pools, contrasting with the surrounding rocky, brown terrain.

The county uses some 2.2 billion gallons Water intake per day – or more twice as many It’s the same as New York City, albeit with half the population.

Arizona’s water problem is beginning to seep into state politics. In January, new Governor Katie Hobbs, a Democrat, promised: first major address Strengthen management of groundwater use around the state.

As evidence of that commitment, Governor Hobbes published a report It has been suppressed by the previous Republican-led administration, she said. It was shown that an area west of Phoenix called the Hassayampa Subbasin did not have enough water to build a new well. As a result, the Arizona Department of Water Resources has announced that it will no longer issue new permits for building groundwater-dependent homes in the area.

But Hassayampa is just one of several sub-basins that make up a larger groundwater basin beneath the Phoenix metropolitan area. Thursday’s state announcement essentially extends its findings to the entire Phoenix area.

On Thursday, Gov. Hobbs tried to reassure Arizonaans that the state would not run out any time soon, and said growth would continue in big cities like Phoenix.

“We will deal with this situation,” she said at a press conference. “We are not running out of water, and we will never run out of water.”

One location most likely to be affected by the new restrictions is Queen Creek.

When Arizona enacted groundwater regulations more than 40 years ago, much of Queen Creek was still peach and citrus orchards and vast farmlands. Today, it’s one of Arizona’s fastest-growing locations, where families go fishing on recycled sewage-fed “oasis” lakes. The town’s population is he 75,000, but he is projected to grow to 175,000 by the time it is built in the next few decades.

But to make that happen, the town needs to find more water.

“We’re looking for about 30,000 acre-feet, or about 9.8 billion gallons,” said Paul Gardner, Queen Creek’s director of utilities.

With insufficient groundwater for future growth, Queen Creek is seeking water wherever possible, transporting water from western Arizona via canals and working with other cities to reach Bartlett Lakes. We are considering a project to expand the reservoir.to build high dam.

Unlike Phoenix, Queen Creek does not have a “designation” from the state. That is, the decision that there is enough water in the city to build new housing. Without this designation, each development plan must prove to the state that it can supply for 100 years. Developers without that stamp of approval will have to look for sources other than groundwater.

The Kill Center warned that Arizona was still pumping too much groundwater, despite the state taking steps to slow the depletion. In its 2021 report, the center found that new industrial projects are sucking up groundwater indefinitely, with water demand outstripping increases from conservation efforts.

Despite increasingly dire warnings from states and water experts, some developers are confident that construction won’t stop anytime soon. The Arizona Water Department has approved the construction of about 80,000 unbuilt residential properties, state officials said.

Cynthia Campbell, a water resources management adviser for the city of Phoenix, said the city relies primarily on river water, with groundwater making up only about 2 percent of its water supply. But that could change dramatically if Arizona suffers a drastic cut in its Colorado River quota, forcing the city to increase groundwater pumping.

Many of the suburban developments and towns in Maricopa County’s sprawl can be built by enrolling in a state-approved program. The program allows subdivisions to pump groundwater elsewhere in the basin when it pumps groundwater back underground.

Ms Campbell said the idea of ​​balancing water supplies in that way was always a “legal fiction,” but it is now clearing up as the state investigates more closely where its groundwater supply is lacking. He said it seems to be on the way.

“This is the return of the hydrological discontinuity to the roost,” Campbell said.

“A lot of developers are really worried and surprised,” Campbell said, in remote areas. “The reality is that they all came back to catch us.”