Arizona has determined there isn’t enough groundwater for all the housing construction already approved in the Phoenix area, and it will prevent developers from building some new subdivisions, a sign of impending trouble in the West and other places where use Excessive flow, drought and climate change are depleting water supplies.
The decision by state officials is likely to spell the beginning of the end of the explosive development that has made the Phoenix area the fastest growing metropolitan region in the country.
The state said it would not revoke building permits that have already been issued and instead is counting on new water conservation measures and alternative sources to produce the water needed for housing developments that have already been approved.
On Thursday, Gov. Katie Hobbs, a Democrat, said Arizona was not running out immediately and new construction would continue in major cities like Phoenix. The state-prepared analysis looked at groundwater levels over the next 100 years.
“We are going to handle this situation,” he told a news conference. “We did not run out of water and we will not run out of water.”
Maricopa County, which includes Phoenix and its suburbs, gets more than half of its water supply from groundwater. Most of the rest comes from rivers and aqueducts, as well as recycled wastewater. In practical terms, groundwater is a finite resource; it can take thousands of years or more to replenish.
The announcement of a groundwater shortage means Arizona will no longer grant developers in some areas of Maricopa County new permits to build homes that rely on wells for water.
Phoenix and nearby large cities, which must obtain a separate permit from state officials for their development plans every 10 to 15 years, would also be denied approval for any homes that rely on groundwater beyond what the state has already authorized.
The decision means cities and developers must seek alternative sources of water to support future development, for example by trying to buy access to river water from farmers or Native American tribes, many of whom face their own shortages. That rush to buy water is likely to shake up the real estate market in Arizona, making homes more expensive and threatening the relatively low housing costs that have made the region a magnet for people from all over the country.
“Housing affordability is going to be a challenge going forward,” said Spencer Kamps, vice president of legislative affairs for the Central Arizona Home Builders Association, an industry group. He noted that even when the state limits housing construction, commercial buildings, factories and other types of development can continue.
Still, the change will act as a signal to developers, said Sarah Porter, director of the Kyl Center for Water Policy at Arizona State University. “We see the horizon for the end of the expansion,” she said.
A groundwater shortage is not likely to derail planned growth anytime soon in major cities like Phoenix, Scottsdale and Mesa, Porter said.
“There is still capacity for development within the designated cities,” Ms. Porter said, referring to cities whose growth plans had already been approved by state water officials. Those cities would not be able to get approval to build homes that rely on groundwater beyond that amount.
The new restrictions would be felt harshest and immediately in small towns and stretches of unincorporated desert along the fringes of the Phoenix metropolitan area, where most low-cost homes tend to be built. “Those have been hot spots for growth,” Ms. Porter said.
The announcement is the latest example of how climate change is reshaping the American Southwest. A 23-year drought and rising temperatures have lowered the Colorado River, threatening the 40 million Americans in Arizona and six other states that depend on it, including residents of Phoenix, which draws water from the Colorado River for aqueduct.
Rising temperatures have increased the rate of evaporation from the river, even as crops require more water to survive those higher temperatures. The water Arizona receives from the Colorado River has already been significantly reduced through a voluntary agreement between the seven states. Last month, Arizona agreed to conservation measures that would further reduce its supply.
The result is that Arizona’s water supply is being squeezed in both directions: the disappearance of groundwater and the shrinking of the Colorado River.
And the water shortage could be more severe than the state’s analysis shows because it assumes Arizona’s water supply from the Colorado will remain constant for the next 100 years, something that is uncertain at best.
The Phoenix area occupies a valley in southern Arizona, cradled by mountain ranges and cut by the Salt and Gila rivers. The landscape is dotted with lush golf courses, baseball diamonds, farm fields, and swimming pools, contrasting with the brown rocky terrain that surrounds it.
The county uses some 2.2 billion gallons of water per day, more than two times more than New York City, despite having half as many people.
Arizona’s water problems have begun to filter through state politics. When she took office in January, Governor Hobbs promised in her first important address to strengthen controls on groundwater use throughout the state.
As proof of that commitment, Governor Hobbs published a report which he said had been suppressed by the previous administration, which was run by Republicans. He showed that an area west of Phoenix, called the Hassayampa sub-basin, does not have enough water for new wells. As a result, the Arizona Department of Water Resources said it would no longer issue new permits in that region for home construction that relies on groundwater.
But Hassayampa is just one of several sub-basins that make up the largest groundwater basin below the Phoenix metropolitan area. The state’s announcement Thursday essentially extends that finding to the entire Phoenix area.
One of the places most likely to feel the impact of the new restrictions is Queen Creek.
When Arizona created its groundwater standards more than 40 years ago, Queen Creek still consisted primarily of peach and citrus groves and extensive farmland. Today, it’s one of the fastest growing places in Arizona, where families go fishing in an “oasis” lake fed by recycled wastewater. The city’s population of 75,000 is projected to grow to 175,000 by the time it is built decades from now.
But to do any of that, the city needs to find more water.
“We’re looking at about 30,000 acre-feet,” or about 9.8 billion gallons per year, said Paul Gardner, Queen Creek utilities director.
Since there isn’t enough groundwater to meet its needs for future growth, Queen Creek is seeking water wherever it can, exploring proposals such as transferring it via a canal from western Arizona, expanding the Lake Bartlett reservoir, joining other cities in a project to build a highest dam.
Unlike Phoenix, Queen Creek does not have a “designation” from the state; essentially, a determination that the city has enough water to accommodate new housing. Without that designation, each proposed development must demonstrate to the state that it has a 100-year supply. Developers without that seal of approval would now have to find sources other than groundwater.
Despite the state taking steps to try to slow the depletion, the Kyl Center has warned that Arizona is still pumping too much groundwater. New industrial projects are sucking up groundwater without restriction, and demand for water is outpacing any gains from conservation efforts, the center found in a 2021 report.
Despite increasingly dire warnings from the state and water experts, some developers say construction won’t stop anytime soon. The Arizona water agency has given permission for construction of some 80,000 home lots that have yet to be built, a state official said.
Cynthia Campbell, a Phoenix water resources management adviser, said the city relies heavily on river water, with groundwater making up only about 2 percent of its water supply. But that could change dramatically if Arizona suffers drastic cuts to Colorado River allocations, forcing the city to pump more groundwater.
Many developments and outlying towns in sprawling Maricopa County have been able to build by enrolling in a state-sanctioned program that allows subdivisions to absorb groundwater in one location if they pump it back into the ground in another part of the watershed.
Ms Campbell said the idea that water supplies could be balanced had always been a “legal fiction”, one that now appears to be unraveling as the state takes a closer look at where groundwater supplies are falling short. .
“This is the hydrologic disconnect coming home,” Campbell said.
In the outlying areas, “a lot of the developers are really worried, scared,” Campbell said. “The reality is that it all came back to get us.”