… How water is used, moved, and managed in the Colorado River Basin is dictated by a series of interwoven compacts, treaties, laws, and court cases that collectively compose what is known as the “Law of the River.” At the center of this legal manual is the Colorado River Compact of 1922. That agreement divided the river between an Upper Basin (Colorado, New Mexico, Utah, and Wyoming) and a Lower Basin (Arizona, California, and Nevada). The Upper Basin had to send a certain amount of water to the Lower Basin. Each basin got an equal slice of the river: 7.5 million acre-feet. But these shares were based on faulty assumptions about supply; They assumed the river’s volume was larger than it was. … This is more pressing now because the rules for how water moves through the river’s infrastructure expire in 2026. The federal government has given the states a deadline of November to come up with a draft of something new. Here’s some of what’s at play.

Other Colorado River Basin news:

• The Land Desk: Blog: Colorado River users come to their senses?
• The University of Arizona: News release: Did a meteor impact trigger a landslide in the Grand Canyon?