The agency responsible for managing water and power in the western US said "urgent action" is needed as water levels in the Colorado River's two largest reservoirs -- Lake Mead and Lake Powell -- continue to drop. Under the new conservation efforts, 21% of Arizona's annual water allocation from the river system will be reduced in 2023. 

Nevada will see 8% of water deliveries reduced, and Mexico's share will be cut by 7%. California will be spared from the new measures that begin next year. 

The reductions could be the beginning of a water crisis for the 40 million Americans in seven states (Colorado, New Mexico, Utah, Wyoming, Arizona, California, and Nevada) that heavily rely on the river for freshwater and power.