Details remain elusive on a new proposal to protect the Colorado River from collapse, but an agreement among the three Colorado River Lower Basin states promises to save at least 3 million acre feet of water between now and the end of 2026.

The states (Arizona, California, and Nevada) are trying to create short-term fixes to declining Colorado River supplies and levels at its two main reservoirs – Lake Mead and Lake Powell – as the 2026 deadline. This is when existing management practices of the Colorado River expire and the seven states that rely upon the river must agree to new long-term river management.

Earlier this year the Department of Interior ordered the states to agree to upwards of 4 million acre feet of cuts from the river or face an edict forced upon them.

Under the agreement, Lower Basin states will reduce their take on the river by at least 3 million acre feet over the next four years. That’s a total number, not an annual one, according to Gage Zobell, a water law expert and partner at the international law firm Dorsey & Whitney in Salt Lake City, Utah. How those cuts are divided among the three states remains to be seen.

According to Zobell, the agreement is over and above existing interim guidelines related to the Drought Contingency Plan and other legal guidelines as they look ahead to the 2026 discussions that will surely require drastic changes in allocations among the states.

Under the agreement announced on May 22, half of the 3 million acre feet “shall be physically conserved by the end of calendar year 2024.” That water will be held back at Lake Mead, according to a statement from Arizona Department of Water Resources Director Tom Buschatzke.

“This proposal protects the system in the short term so we can dedicate our energy and resources to a longer-term solution, said Brenda Burman, general manager, Central Arizona Project, in a prepared statement.

The agreement aims to prevent Lake Mead from falling below 1,000 feet elevation, and to keep Lake Powell from falling below 3,500 feet elevation. Lake Powell was within 23 feet of that in late April before recovering more than 25 feet amidst significant snow melt and runoff. Mead is up about three feet in elevation since the beginning of May.

Because of the agreement, the U.S. Department of Interior will temporarily withdraw its draft supplemental environmental impact statement on river management to fully analyze the agreement’s impacts. The draft EIS process on near-term operations of the Colorado River will continue later this year, according to a statement from Interior.

The Interior department statement also says that the federal government will compensate up to 2.3 million acre feet of savings through the Inflation Reduction Act. That money is said to go to support near-term water conservation and long-term efficiencies.