(Image source from: High Country News)

Arizona water officials pledged on Thursday to reach a multi-state program by the end of the year to stave off Colorado River water deficit, or at least diminish the consequence.

The United States Bureau of Reclamation has been urging Western states to wrap up drought contingency plans, one each in the lower and upper basins. Little snowpack, rising temperatures, and ongoing drought have led to a regular diminution in the river that serves 40 million people in seven U.S. states.

Depending on Lake Mead, the reservoir formed by Hoover Dam, the amount of water is sent to the lower basin states, comprising Nevada, Arizona, California, and Mexico. No shortfall has ever been announced, but the federal agency puts the outlook at more than 50 percent in 2020 and even higher in subsequent years.

Those states so far have avoided shortages through conservation, leaving water in Lake Mead and other efforts.

"The question is: How much of this do we need to do in the future and how can we stay out of shortage?" said Terry Fulp, director of the Bureau of Reclamation's Lower Colorado River Region. "The likelihood is that we probably can't."

The Arizona Department of Water Resources and the Central Arizona Project said they would form a committee to work out the details of a drought plan among Arizona water users and present it to the Legislature in January.

Right now, shortages begin when Lake Mead dips to 1,075 feet (328 meters) above sea level. Arizona is hit first and hardest as the junior user in the system.

Burman said other states would pressure her agency to limit Arizona's water deliveries if it doesn't agree on the drought plan. She also predicted lawsuits.

The federal agency has said it would rather the states negotiate a solution.

"That creates this real uncertainty," said John Fleck, director of the University of New Mexico's Water Resources Program. "No one knows exactly where and when they would step in and what that stepping in would look like."

American Indian tribes are hoped-for to play a big role in the plan because they hold senior water rights and do not yet have the infrastructure to use their entire shares.

Gila River Indian Community Gov. Stephen Roe Lewis said the tribe is "fairly confident" a plan will be complete this year, given Reclamation's leadership and renewed cooperation between Arizona water officials.

By Sowmya Sangam