Remarkable drop in Colorado River water use a sign of climate adaptation

Use of Colorado River water in the three states of the river’s lower basin fell to a 33-year low in 2019, amid growing awareness of the precarity of the region’s water supply in a drying and warming climate. Arizona, California, and Nevada combined to consume just over 6.5 million acre-feet last year, according to an annual audit from the Bureau of Reclamation, which is about 1 million acre-feet less than the three states are entitled to use.