Today's Guardian has a feature story, "Paving America", on the flood of Americans to Arizona. It protends an environmental calamity to come:
The state has the fastest growing population in the country, recently overtaking Nevada, which held the title for 19 years. In 1950 there were 750,000 Arizonans; in 2000 there were almost 5 million and in 2020 there are projected to be 7.4 million.
Phoenix, the state capital that lies about 50 miles east of the White Tank mountains, is the fastest growing city in America. It covered 17 square miles in 1950; now it sprawls over almost 500, an area larger than Los Angeles.
"Thousands descend every year on Arizona, led by baby-boomers reaching retirement. They come mainly from other parts of the US - from California where land is increasingly expensive, and the midwest, where the winters are severe. And each new arrival is looking to build a castle in the desert, the epitome of the detached, individualistic and car-dependent American dream.
"For residents ...the attractions are palpable: more space for their bucks, eternal summers and fulfilment of what remains of the west's original frontier spirit.
"But the costs are high too. Arizona's water table is being depleted as a result of homes being built on pristine desert rather than on agricultural land already used to grow thirsty crops such as cotton and alfalfa. Air quality is suffering from dust thrown up from developments and car exhausts, and highways are clogged with commuters travelling to and from the desert communities. In Phoenix, widening one of the main intersections to 24 lanes, 12 in each direction, has been mooted.
"'At what point do we just stand up and start screaming?' said Wellington Reiter, dean of Arizona State University's design college, who has been involved in creating a light rail system - a first step towards public transport.
"But he fears the pace of growth in the opposite direction, comparing the carbon footprint (the amount of greenhouse gas emissions caused by each person every year) of Phoenicians: 1,400kg, with that of the people of Hong Kong: 50kg.
"Environmentalists tried unsuccessfully to introduce tougher restrictions on development in Arizona in 2000. Sandy Bahr of the state's Sierra Club said the unlikely alliance between developers and farmers hoping to make a fortune by selling their land for housing complexes proved too powerful.
"'The policy-makers are burying their heads in the sand. Our whole economy is based not just on growth, but on rapid growth,' she said.
"With the American population passing 300 million, and projected to reach 400 million by mid-century, Arizona is the most extreme example of stresses being played out across the States. America is being paved over. Some estimates suggest that more than half of the built environment that will exist in the US in 2025 will have been constructed since 2000."
With peak summer temperatures that already reach 46C and are expected to climb higher yet simply surviving in this region is astonishingly energy intensive. Most of the year you don't need much in the way of heating but you do consume terrific amounts of energy for air conditioning, irrigation and transportation, all to live in a place which has no sustainable water supply.