Arizona is facing a water crisis as years of drought and climate change have depleted its groundwater resources.
The state has announced new limits on construction in the Phoenix area, one of the fastest-growing metropolitan regions in the country, to prevent further water shortages and protect the environment.
The decision has implications for the future of development and growth in the state, as well as for the millions of people who depend on water from the Colorado River and other sources.
Phoenix faces water shortage as climate change worsens
ORLANDO SIERRA/AFP via Getty Images
New houses that rely on dwindling groundwater supplies around one of the United States' biggest cities are to be banned, officials said Thursday, in a sign of the strains that drought and climate change are causing across the US West, as per Phys.org.
Water managers in Arizona say there is a significant shortfall in the Phoenix area, and that any more development in the fast-growing city must rely on other sources of water-such as under-strain rivers.
"Over a period of 100 years, the Phoenix (area) will experience 4.86 million acre-feet of unmet demand for groundwater supplies," the Arizona Department of Water Resources said.
An acre-foot is the amount of water it takes to cover an acre with a foot of water-around 326,000 gallons (1.23 million liters)-and is equivalent to around half an Olympic-size swimming pool.
"The term 'unmet demand' refers to the amount of groundwater usage that is simulated to remain unfulfilled as a result of wells running dry."
The western United States is in the grip of a more-than-two-decade drought and long-term aridification, which scientists say is being exacerbated by human-caused climate change.
Major rivers that cross the region, among them the Colorado River, have long been over-exploited, with far more water removed every year than falls as rain or snow.
This has led to shrinking reservoirs, including the enormous Lake Mead, which last year dropped to just a quarter of its capacity, threatening "Deadpool"-the point where the river downstream dries up and hydroelectric power production ceases.
With rivers under pressure, fast-growing population centers have long tapped groundwater to provide water for homes and agriculture, in the form of wells.
But this source is easily over-exploited and can in some cases take thousands of years to be replenished.
Developers face new restrictions on construction permits
State officials said permits already issued for developments in Maricopa County, in which Phoenix sits, will not be rescinded, but developers will have to prove any new applications have a sustainable water source other than groundwater.
"The constraints regarding the physical availability of groundwater are attributable to the cumulative results of decades of groundwater overdraft and the continued reliance on groundwater resources," the Arizona Department of Water Resources said, as per Manila Times.
Phoenix, the country's fifth-largest city, is home to around five million people and is one of the fastest-growing metropolitan areas in the United States
The announcement Thursday is the latest move in a long battle over water in the US West.
Last month states that rely on the Colorado River reached an agreement on cutting the amount of water they take from the lifeblood of the region.
Around 40 million people including Los Angeles, Las Vegas, and Phoenix depend on the river.
