Las Vegas gets 90 percent of its water from the Colorado via the lake, which is located just east of the gambling and tourist mecca. One of the most ambitious efforts is a new $1.35 billion, 24-foot-wide tunnel - the so-called Third Straw - that Las Vegas drilled at the very bottom of Lake Mead to function like a bathtub drain. Many cities and towns in the Southwest - including Los Angeles, San Diego, and Albuquerque - are trying to figure out solutions to a dwindling Lake Mead, the key reservoir on the Colorado. “You could hit dead pool in four years,” Sorensen said. And Phoenix may need the water sooner than it planned. Phoenix may have enough water to secure its near-term future, but it still needs to build $500 million of infrastructure to pipe it to northern parts of the city that now rely on Colorado River water. These days, Phoenix’s alternative water supplies are not dependent on the Colorado. “I can survive dead pool for generations,” says Sorensen, pointing to a host of conservation and water storage measures that have significantly brightened the city’s water outlook in an era of climate change and drought. And what of the dreaded “dead pool,” the point at which the level in the giant man-made lake falls so low that water can no longer be pumped out?Īs Colorado River supplies dwindle, Kathryn Sorensen, director of Phoenix Water Services, is racing to find new ways to conserve and store water for the sprawling city of 1.6 million people. “We are fully prepared to go into Tier 1, 2, and 3 emergency,” said Kathryn Sorensen, Phoenix’s water services director, referring to federally mandated cutbacks of Colorado River water as the levels of Lake Mead, the source of some of the city’s water, continue to drop. But while the Hohokam succumbed to the mega-drought, the city of Phoenix and its neighbors are desperately scrambling to avoid a similar fate - no easy task in a desert that gets less than 8 inches of rain a year. The fate of the Hohokam holds lessons these days for Arizona, as the most severe drought since their time has gripped the region. The people who had mastered farming dispersed across the landscape. It is believed to be a primary cause of the collapse of Hohokam society. Then in 1276, tree ring data shows, a withering drought descended on the Southwest, lasting more than two decades.

Hohokam civilization was characterized by farm fields irrigated by the Salt and Gila rivers with a sophisticated system of carefully calibrated canals, the only prehistoric culture in North America with so advanced a farming system. The Hohokam were an ancient people who lived in the arid Southwest, their empire now mostly buried beneath the sprawl of some 4.5 million people who inhabit modern-day Phoenix, Arizona and its suburbs.

City of phoenix water supply