After a more than 40-year absence, adult salmon will swim again in the Upper Deschutes River, starting today.

“We are returning the missing link,” said Brett Hodgson, district biologist for the Oregon Department of Fish and Wildlife in Bend.

A ceremony is planned this morning, with speakers from Portland General Electric, the Confederated Tribes of Warm Springs and ODFW. The power company and tribes are the owners of the hydroelectric project, which produces enough electricity to supply a town the size of Salem, while the state agency oversees the fishery on the river.

Jim Bartlett, fish passage biologist with PGE, is set to drive the truck carrying the first fish — about a half dozen or so — about 10 miles around the Pelton Round Butte dam complex. A biologist from the tribes will also be aboard.

“It’s a glorious day for everybody, and the fish,” Bartlett said.

Millions spent

PGE and the tribes spent more than $100 million on a submerged tower, completed in late 2009, which restarted fish migrating downstream. Since then, young salmon — both chinook and sockeye — and steelhead have been released upstream of the dam complex, passing through the tower en route to the sea.

Collected by the tower, the fish are hauled around the dam complex on their way downstream.

Now the fish are returning as adults, and the effort is beginning to return half of them to the waters where they grew up, said Mike Gauvin, ODFW mitigation coordinator at the dam complex.

In all, the scientists involved with the project hope to see about 400 adult chinook return this year, with about 200 moved upstream, but so far the run has been low and late.

Just to make sure there are enough fish for today’s ceremony, some adults — which were likely released as fry upstream of the dams in winter 2009 — have been kept at the Round Butte Fish Hatchery.

“We are hoping we have at least 10,” Gauvin said.

‘Trap-and-haul’

The three dams of the complex, built in the 1950s and ’60s, created a blockade for migrating salmon and steelhead. But the hitch was with downstream migration of young salmon, rather than the upstream migration of the adults. Adult fish returning from years at sea found their way up and around the dams, using a 3-mile fish ladder and a tramway, but confusing currents in Lake Billy Chinook caused their ocean-bound offspring to become lost.

In the late 1960s, a state interagency committee decided to replace the Upper Deschutes salmon and steelhead run with a hatchery, which was completed at the base of Round Butte dam in 1968. A similar committee, led by the ODFW and the tribes, led the plans to reintroduce adult fish following a new federal power license for PGE that called for improved fish passage.

To move the adult fish upstream, scientists are using a “trap-and-haul” technique. The trap is at the entrance to the old fish ladder. There, scientists collect adult fish trying to swim upstream and sort through them, separating fish headed to the hatchery and those staying in the river.

The fish are trapped at river mile 100 and will be hauled and then released at river mile 110, Bartlett said. The trip should take about 20 minutes.

“It’s really completing the upstream migration,” he said. “It’s completing the life cycle.”