In 1922, as part of the Colorado River Compact, the Colorado River was divided into two basins:  The Upper Basin comprised of Colorado, New Mexico, Utah and Wyoming and the Lower Basin comprised of Arizona, California, and Nevada.  The Compact established the amount of water allocated to each and has managed the river for the past century.  Unfortunately, these water decisions were made during some of the wettest years on record and long before the region’s population skyrocketed and climate change evolved, creating a systematic overallocation of the river’s water.[1]

In 2007, in response to a lengthy drought and facing alarming drops in both Lake Mead’s and Lake Powell’s elevations, the plan was revised to improve operations at both reservoirs, to accelerate conservation efforts, and to outline a series of tiers that would trigger predetermined cutbacks.  The Drought Contingency Plans were added in 2019 as an addendum to the plan.  Based on those agreements, the federal government declared the first water shortage on the river in August 2021, identified as Tier 1, which triggered cuts in annual allotments to Arizona, Nevada, and Mexico that began January 2022. 

In June of this year, the Department of the Interior gave those states 60 days to develop a plan to provide an additional reduction of 15 percent to safeguard the water levels in the reservoirs and subsequently protect deliveries to 40 million people who rely on the river and ensure hydroelectric power generation for hundreds of thousands of people.  The states failed to meet the deadline.   

Now, the Federal Bureau of Reclamation announced that the river dropped to levels of a Tier 2 shortage, triggering additional cuts effective January 2023: Arizona will feel the pressure of an additional three percent reduction for a total of 21 percent, Nevada will lose an additional percent for a total of eight percent, and Mexico will go from five to seven percent total reduction. The additional cuts will force the states to make unpleasant decisions.  In Arizona, many of the original reductions were given to farmers, but the new round of cuts will likely extend to tribes and growing cities.  Some cities are likely to navigate the situation engaging alternate sources, such as the Salt and Verde rivers, as well as retain supply instead of sending it to recharge groundwater.  Once again, California will see no cutbacks as the state with most senior water rights, a vexing reality to the three facing cuts as California draws the most water, more than one third of the river’s natural flow.[2]

It remains to be seen how the Inflation Reduction Act will impact the crisis.  The new law includes $4 billion in funds for drought relief, and although the funds will help mitigate the Colorado River water crisis, states will still have to make the tough decisions they have avoided thus far.  Failure to act only will only serve to accelerate the crisis.

[1] State of the Rockies Project 2011-12 Research Team. “The Colorado River Basin: An Overview.” Coloradocollege.edu, 2012, https://www.coloradocollege.edu/dotAsset/e57e7c73-2983-477b-a05d-de0ba0b87a00.pdf.

[2] Becker, Rachel. “Colorado River Water Cut Back - except for California.” CalMatters, 16 Aug. 2022, https://calmatters.org/environment/2022/08/colorado-river-water-california/.