California has refused to join other states in a plan to cut water from the dwindling supply in the Colorado River, The Washington Post reported.

The other six states in the Colorado River Basin submitted a joint proposal to the U.S. Bureau of Reclamation on Monday to help shape management of the river’s limited water supply.

Sen. Michael Bennet, D-Colo., said in a news release, “The Colorado River is running out of water, and if we don’t act soon, we could lose much of the American West as we know it.”

Six of the seven states in the Colorado River Basin — Colorado, New Mexico, Utah, Wyoming, Arizona and Nevada — did exactly what we needed,” Bennet said. “ We forged a common vision that will protect the Colorado River and the 40 million people, and more than 30 Tribes, who rely on it.

“California’s decision not to join this consensus is deeply disappointing. We are facing the most serious drought in 1,200 years. California must step forward and be part of the solution. For too long, the other six states, and particularly the Upper Basin, have carried the burden of this historic drought.

“I urge Interior Secretary [Deb] Haaland to recognize the leadership of these six states and enact their consensus proposal.”