A Watershed Moment

A “mega-drought” across the Southwest will force the federal government to declare a water shortage on the Colorado River this month. The decision would be historic for the watershed, which serves 40 million people in seven states: California, Arizona, Nevada, New Mexico, Utah, Colorado and Wyoming. The river system provides irrigation that turns desert into farmland and is an important source of drinking water and hydroelectric power. The looming first-ever declaration will be triggered when the country’s largest reservoir, Lake Mead, dips below a certain level.