After years of drought, the federal government has declared a shortage of water on the Colorado River system for the first time in history, triggering mandatory water cuts at Lake Mead that will largely impact Arizona farmers. “As this inexorable-seeming decline in the supply continues, the shortages that we’re beginning to see implemented are only going to increase,” said Jennifer Pitt, director of the Colorado River program. “Once we’re on that train, it’s not clear where it stops.” So far, the shortage only affects lower basin states such as California, Nevada, and Arizona but shortages in the upper basin could appear by next year. Lake Mead typically holds nearly 30 million acre-feet of water but currently has less than half of that, the result of drought and the warming climate. “The river is in uncharted territory,” said Kevin Moran, senior director of the Colorado River Program, adding that much of the river’s decline is due to climate change.