Is Arizona's most populous city ready for a future with less Colorado River water? During the past century the Colorado River's flow has declined by about 16 percent, a decrease scientists say is largely due to climate change. Seven states and portions of Mexico rely on the river for water supplies, including in Arizona, which is now in its 19th year of drought and recently passed a key piece of water legislation that outlines the steps the state would take if water from the Colorado River continues to decline. But what does a looming water shortage mean for Phoenix, the state's most populous city? Hari Sreenivasan traveled there to find out how it is preparing for a future with less water.