New Colorado River plan orders cuts for Arizona, California, Nevada

Federal officials on July 31 released a Colorado River plan that would require Arizona, California and Nevada to curb their water use by about 20 percent over the next two years. The proposal puts the heaviest immediate burden on the lower basin while leaving the upper basin states out of mandatory cuts for now.

The Colorado River Basin spans about 250,000 square miles, the river runs roughly 1,400 miles, and it supplies water to more than 40 million people across seven U.S. states and Mexico. With Lake Mead and Lake Powell already at historically low levels and the combined storage in those reservoirs falling to its lowest point since 1957, the new plan is aimed at keeping water deliveries and hydropower from slipping further into crisis.

The 2007 Colorado River Interim Guidelines, which have governed the system from 2008 through 2025, are set to give way at the end of 2026, when several reservoir and water-management agreements also expire. The Bureau of Reclamation’s post-2026 process will set new operating rules for Lake Powell and Lake Mead after nearly two decades of emergency management.

Arizona, California and Nevada have tried to shape those rules before they harden into law. On May 1, the three lower-basin states advanced a plan calling for more than 3.2 million acre-feet of conservation through 2028, including at least 700,000 acre-feet on top of the 1.25 million acre-feet in annual lower-basin reductions they had proposed earlier. California submitted comments on the draft environmental impact statement on March 2, and Arizona Gov. Katie Hobbs said the federal government’s released alternatives still left room for a compromise plan.

In February, the governors of Arizona, Nevada and California issued a joint statement on the deadline, while the 2019 Colorado River Drought Contingency Plan remained the earlier emergency backstop if the system deteriorated further.

Arizona would absorb the largest share of the cuts under the new proposal, and estimates put reductions as high as 40 percent in the driest conditions.