The Colorado River plan was finalized by the federal government, making the water cuts for the Lower Basin states official.
Guidelines were announced by the U.S. Department of the Interior on Aug. 21. The Lower Basin states – Arizona, California and Nevada – typically receive 7.5 million acre-feet of water each year. The new plan will reduce that total by 1.25 million acre-feet.
This was expected, as it was essentially what the states had offered to give up. The three states have, however, asked the four Upper Basin states – Colorado, New Mexico, Utah and Wyoming – to commit to reductions if more are necessary.
The first set of guidelines covers two of the ten years within the new framework. The next decade could see further reductions depending on river conditions. All the while, the Department of Reclamation is looking into other ways to modernize infrastructure and create conservation programs to help sustain the water supply.
Arizona is set to endure the heaviest cut at 760,000 acre-feet. This is due to the lower legal priority of the Central Arizona Project. Nevada, which has the smallest allocation, will face a reduction of 50,000 acre-feet. California is set to lose 440,000 acre-feet. A single acre-foot can provide water for roughly three households over the course of a year.
The worst-case scenario would see the Lower Basin facing a 3 million acre-foot reduction. The current two-year plan is intended to serve as a buffer and allow further negotiations.
The federal plan aims to protect the minimum water elevation in Lake Powell to ensure power generation at Glen Canyon Dam. Water conditions will be monitored, and flows will be adjusted to maintain a buffer at the dam.
The first annual release will be delayed from August to April to accurately account for water from the winter’s snowpack.
Typically, Lake Powell spills more than 8 million acre-feet over the course of the year. A two-year forecast indicates that, as long as it receives at least 6 million acre-feet, Lake Mead will be able to continue to generate power. Opponents of the plan argue Lake Mead is being sacrificed to protect Lake Powell and the Upper Basin.
Arizona Impact
The State of Arizona has set aside funding for a potential Supreme Court legal battle if it must take on additional water cuts. Gov. Katie Hobbs said the lack of cuts in the Upper Basin could put Lake Mead at risk and serve as a threat to downstream users.
While Arizona residents are not expected to lose tap water, the reductions will force cities and water providers to use more groundwater. (Source: Arizona Daily Star)