Interior locks in 1.25 million acre-feet of Colorado River cuts for 2027 and 2028

The Interior Department has signed operating guidelines that cut Lower Basin deliveries from the Colorado River by 1.25 million acre-feet in each of 2027 and 2028. If California, Arizona and Nevada keep their own sharing deal, Arizona takes 760,000 acre-feet of that cut, California 440,000 and Nevada 50,000. The three states also pledged to conserve at least 700,000 acre-feet over the two years on top of the mandatory reduction.

Secretary Doug Burgum signed the Record of Decision for the post-2026 operations final environmental impact statement. The document sets a 10-year decision framework. Actual operating rules will be rewritten every two years inside that frame. Upper Basin states, Colorado, Utah, New Mexico and Wyoming, face no mandatory cuts in this round.

The reservoirs are at the floor of the record

Lake Mead's surface sat at 1,038.94 feet on 27 August, according to Bureau of Reclamation gauge data compiled by ReservoirBench. That is the lowest reading in a daily series that starts in 1935, and it is 26.4 percent of the 26.12 million acre-foot capacity used on that site. Storage was 6.90 million acre-feet. The lake has fallen 0.50 feet in a week, 2.19 feet in a month and 16.29 feet in a year.

Lake Powell, the other half of the system, has been setting its own lows this month. The combined contents of Powell and Mead have not been this small since before Powell filled after Glen Canyon Dam closed in 1963. Reclamation's August 24-month study puts Powell at the start of the water year between 3,540 and 3,510 feet, in the Lower Elevation Infrastructure Protection Range, with a water-year release of 6.0 to 7.0 million acre-feet. The 3,510-foot floor is the line the new guidelines treat as the minimum for keeping Glen Canyon's turbines reliable.

A bridge with a larger cut behind it

California's lead negotiator called the two-year package a workable path and "a bridge, not a permanent solution." The 10-year framework allows later two-year plans to raise Lower Basin cuts as high as 3 million acre-feet a year, about 40 percent of the three states' combined allotment. Arizona has said cuts on that scale would wreck its economy and has threatened to sue if they are imposed.

One acre-foot is 325,851 gallons, enough for two to four houses for a year. A 1.25 million acre-foot cut is not a rounding error for Phoenix, Las Vegas or the Imperial Valley. California's share, 440,000 acre-feet, is about 12 percent of its Colorado River take. Arizona's 760,000 is about 31 percent. Nevada's 50,000 is about 28 percent.

The announcement did not mention climate change. It described a 26-year drought, record-low runoff and reservoirs that have been falling since the late 1990s. Cities and farms that have lived on a 1922 compact written for a wetter river now have two years of fixed cuts and eight years of rules that can get tighter. The next rewrite is scheduled before 2029. By then Mead will either have climbed off 1,038.94 feet or the 3 million acre-foot clause will be the argument that lands in court.