Sen. Larry Craig and Idaho water users oppose a bill to protect 387 miles of the Snake River and its tributaries in Wyoming, which was sent to the Senate floor last week with a package of other bills, including Crapo's Owyhees bill.

Craig has opposed the Craig Thomas Snake Headwaters Legacy Act from the start, saying it presented a threat to Idaho irrigation farmers downstream.

It is still not clear the two bills will be in the same package on the floor, Crapo said Friday. But he's committed to resolving the Wyoming dispute anyway, so Idaho's water rights are preserved and Wyoming gets the protection it wants.

"I am working very hard to find a path forward," Crapo said.

The bill, first introduced by the late Republican Wyoming Sen. Craig Thomas, has wide support, including from Vice President Dick Cheney, a former Wyoming lawmaker.

"It has become a legacy issue," Crapo said.

"I really see this as a badge of honor for our rivers," said Wyoming Sen. John Barrasso, the Republican who succeeded Thomas.

But irrigation districts around Twin Falls own the rights to most of the water stored in Jackson Lake inside Grand Teton National Park. Craig and the Idaho Water Users Association say a Wild and Scenic Rivers designation, especially for the stretch of river below Jackson Lake, could change the times water is released from the Jackson Lake Dam or provide a legal platform for environmentalists to sue to reduce Idaho's control over Wyoming's water.

The water rights involved are among the most valuable in Idaho. Most of the Magic Valley's farm economy depends in part on these rights - and they also are critical to the state's future industrial growth.

"Idaho's water user community has a long, painful history of dealing with federal bureaucrats and environmental groups who try to manipulate policies, statutes or rules to achieve results never intended," said Norm Semanko, executive director of the Idaho Water Users Association. "Given that track record, it is only a matter of time before those same forces attempt to use any federal protected river designation to drive Jackson Lake water management, resulting in reduced water storage supplies for Idaho irrigators."

Washington, D.C., attorney Bill Horn, who was assistant secretary of interior for fish, wildlife and parks in the Reagan administration, said language added by Barrasso ensures the bill won't affect the management and operation of Jackson Lake or Jackson Lake Dam. He points to similar language in a bill in Colorado that was challenged when a federal dam was nearly drying up a river.

The courts held that the clear language kept dam operations in place despite the river being designated as wild and scenic.

"When you look at that kind of case law and the language of Sen. Barrasso's bill, I'm confident that Idaho interests are adequately protected," Horn said.

Water users fear the new law will give recreational boaters and outfitters more clout in annual negotiations with the Bureau of Reclamation, which operates Jackson Lake Dam.

The bureau tries to maximize the flows during the summer, when millions of tourists come to Jackson Hole, without affecting Idaho water rights.

But the bureau reads the changes made by Barrasso as he intended. The law would not affect dam operations, nor would it shift the balance in the negotiations, said Diana Cross, a bureau spokeswoman in Boise.

"They may have a different interpretation than we have," she said of Semanko's group.

Crapo has worked hard for six years to hold together the coalition of ranchers and environmentalists who back his Owyhees bill, which would protect 517,000 acres as wilderness and another 315 miles of rivers as wild and scenic, and help ranchers with a series of land transfers, buyouts and the establishment of a science center.

Resolving the Snake River issues is similar to the challenges of resolving the differences among members of the Owyhee group, Crapo said.

He expects the bills sent to the floor Wednesday will be debated sometime in June.

"There is no doubt there is some intent on the part of many senators to help Craig Thomas out," Crapo said. "There is also a very strong desire we manage the property rights issues properly."