PHOENIX (AP) — Arizona won’t have all the pieces of a Colorado River drought plan finished by the federal government’s deadline to finalize protections for water used by millions across the U.S. West, state water officials said Tuesday.

It’s the latest hurdle threatening the plan between seven states to take less water from the drought-starved Colorado River, which supplies 40 million people and 5.5 million acres of farmland. Missing the March 4 deadline could allow the federal government to step in and decide the rules.

About half of the 15 agreements that Arizona needs to secure among water users will be ready by March 4, said Ted Cooke, director of the Central Arizona Project, which brings Colorado River water to the sprawling cities and farm fields around Phoenix and Tucson.

“That’s an artificial deadline, and these are very complex agreements and very complex negotiations, and we will take the time that we need to do them properly,” Cooke told reporters Tuesday following a meeting of water users working on the drought plan.

He said he hopes to finalize all the agreements within 60 days.

Wyoming, Colorado, New Mexico, Utah and Nevada have joined drought contingency plans for the Colorado River, while Arizona and California are still working on plans.

Arizona lawmakers have approved the drought plan, but U.S. Bureau of Reclamation Director Brenda Burman has said the state also must finalize the complex agreements needed to implement it.

If that’s not done by March 4, Burman says she will ask governors what should happen next — starting a process that could result in federally mandated cuts instead of the voluntary plans negotiated by the states. That’s particularly worrisome in Arizona, which has the lowest-priority water rights on the Colorado River.

Cooke repeatedly declined to speculate on what would happen if the state doesn’t finish its work by the deadline. But he said Arizona would probably be done before the federal government could get very far down an alternative path.

Also Tuesday, Arizona House Speaker Rusty Bowers put a measure on hold that angered a key player in several agreements the state is trying to finalize. The Gila River Indian Community has said it will back out of the drought plan without assurances the legislation will die, and it wasn’t clear if Bowers’ move would be sufficient.

The measure would alter the state’s five-year “use it or lose it” water rights law, which the tribe says would undermine its rights to water from its namesake river, secured in 2004 following decades of litigation.

“The community cannot be singled out for legislative attack by the most powerful members of the Arizona House of Representatives and still view itself as a genuine partner in solving the state’s water crisis,” Gila River Gov. Stephen Roe Lewis said. “We view this as slap in the face of the community.”

Bowers put off his measure following a public hearing in a House committee, where several farmers from eastern Arizona told lawmakers that they were concerned about preserving their income and way of life.

“This not only affects us, but it affects our children and grandchildren who have farming in their blood and would love to continue our family farming operation,” Lois Reynolds said.

Bowers said he wants to talk to lawyers and see if there’s another way to allow farmers to fallow their fields for more than five years without surrendering their water rights.

Don Pongrace, a lawyer for the Gila River Indian Community, said it wasn’t clear if the measure was dead so that the tribal council could schedule a vote on joining the drought plan.

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