Arizona is restricting new construction in the Phoenix area, citing shrinking water supplies
Arizona has determined that there is not enough groundwater for all future housing already approved in the Phoenix area, and will deter developers from building new subdivisions, a sign of looming problems in the West and other places where overuse, drought and climate change puts pressure on the water supply.
The decision by government officials marks the beginning of the end of the explosive development that has made the Phoenix metropolitan area the fastest growing region in the country.
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 sewage. In practice, groundwater is a finite resource; it can take thousands of years or more to be replenished.
The announcement of a groundwater shortage — what the state calls an “unmet demand” for water for the next 100 years — means Arizona will no longer give developers in areas of Maricopa County new permits to build homes that rely on wells for water.
Phoenix and nearby major cities, which must get separate approval from state officials every 10 to 15 years for their development plans, would also not receive approval for homes that rely on groundwater beyond what the state has already allowed.
The decision means cities and developers will need to look for alternative sources of water to support future development, such as trying to buy access to river water from farmers or Native American tribes, many of whom are facing shortages of their own. That rush to buy water is likely to rattle the Arizona real estate market, making homes more expensive and jeopardizing the relatively low housing costs that had made the region a magnet for people from all over the country.
“We’re seeing the horizon for the end of sprawl,” said Sarah Porter, director of the Kyl Center for Water Policy at Arizona State University.
The state says it will not revoke permits already issued and is instead counting on water conservation measures and alternative sources to produce the water needed for approved projects.
A groundwater shortage was unlikely to derail short-term planned growth in major cities like Phoenix, Scottsdale and Mesa, Ms. Porter said.
“There is still capacity for development within designated cities,” said Ms. Porter, referring to cities whose growth plans had already been approved by state water officials. Those cities wouldn’t be able to get approval to build anything above that amount.
The new restrictions would be felt hardest and most directly in small towns and unincorporated desert areas along the edge of the Phoenix metro area — where most lower-cost homes are built. “Those have been growth hotspots,” Ms Porter said.
The announcement is the latest example of how climate change is changing the American Southwest. A historic 23-year drought and rising temperatures have lowered the level of the Colorado River, threatening the 40 million Americans in Arizona and six other states that depend on it, including the residents of Phoenix, who take water from an aqueduct. get the Colorado.
Rising temperatures have increased the river’s evaporation rate, even though crops need more water to survive those higher temperatures. The water Arizona receives from the Colorado River has already been significantly reduced by a voluntary agreement between the seven states. Last month, Arizona agreed to conservation measures that would further reduce landings.
As a result, Arizona’s water supply is under pressure from both directions — both the disappearing groundwater and the shrinking Colorado River.
And the water shortage could be more severe than the state’s analysis suggests, as Arizona’s supply from the Colorado is believed to remain constant for the next 100 years — something that is uncertain.
Arizona’s water problems are starting to seep through state politics. In January, the new governor, Katie Hobbs, a Democrat, promised her first major address to tighten controls on groundwater use throughout the state.
As proof of that commitment, Mrs. Hobbs issued a report which she said had been suppressed by the previous Republican administration. It showed that an area west of Phoenix called the Hassayampa sub-basin doesn’t have enough water for new wells. As a result, the Arizona Department of Water Resources said it would no longer issue new permits for housing that relied on groundwater in that region.
But Hassayampa is just one of several subbasins that make up the larger groundwater basin below metropolitan Phoenix. The state’s announcement on Thursday essentially expands that finding across the Phoenix area.
One of the places likely to feel the effects of the new restrictions is Queen Creek.
When Arizona enacted its groundwater regulations more than 40 years ago, Queen Creek was still mostly peach and citrus groves and extensive farmland. Today it is one of the fastest growing places in Arizona, where families go fishing in an “oasis” lake fed by recycled sewage. The city’s population of 75,000 is expected to grow to 175,000 by the time the city has been built out over decades.
But to do all that, the city needs to find more water.
“We’re looking at about 30,000 acre feet” — or about 9.8 billion gallons, said Queen Creek utility director Paul Gardner.
With not enough groundwater to meet its needs for future growth, Queen Creek scavenges for water wherever it can. build one higher dam.
Unlike Phoenix, Queen Creek has no so-called “designation” from the state – essentially a determination that the city has enough water to support new homes. Without that designation, any proposed development would have to prove to the state that it has a 100-year supply — and developers without that seal of approval would now have to find sources other than groundwater.
Even as the state takes steps 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 restrictions and water demand is outpacing conservation gains, the center said in a 2021 report.
Despite increasingly dire warnings from the state and water experts, some developers are confident construction won’t stop anytime soon. The Arizona water agency has authorized the construction of about 80,000 homes that have yet to be built, a state official said.
Cynthia Campbell, Phoenix’s water management consultant, said the city is largely dependent on river water and groundwater accounts for only about 2 percent of its water supply. But that could change dramatically if Arizona is hit by drastic cuts to its Colorado River allotments, forcing the city to pump up more groundwater.
Many outlying developments and towns in the sprawl of Maricopa County have been able to build by enrolling in a state-authorized program that lets subdivisions suck up groundwater in one place when they pump it back into the ground elsewhere in the basin.
Ms. Campbell said the idea that you could balance water resources that way had always been a “legal fiction” — one that now seems to be unraveling as the state takes a closer look at where groundwater resources are falling short.
“This is the hydrologic decoupling coming home to rest,” Ms Campbell said.
In remote areas, “a lot of developers are really worried, they’re crazy,” Ms. Campbell said. “The reality is it all came back to get us.”