MADRAS -- The nearly 400-foot-tall Round Butte Dam holds back a river that drains an area the size of Massachusetts. Behind it, Lake Billy Chinook lies cold and clear in the winter. By July, it will be a soup of algae and boat motor oil. 

For 33 years, this wall of earth and concrete and the stagnant water behind it have blocked the ancient runs of salmon and steelhead that once spawned in the Deschutes River Basin. Now, biologists think they've found a way to bring back those fish runs. 

The plan may cost Portland General Electric and the Confederated Tribes of the Warm Springs Reservation $30 million, but they appear ready to pay to continue operating the three dams of the Pelton-Round Butte Hydroelectric Project. 

The plan centers around a new intake tower, the structure that funnels water from the reservoir through the generators' turbines. Researchers say the existing tower altered currents in the reservoir so juvenile fish could not find their way out. 

Amy Stuart, a biologist with the Oregon Department of Fish and Wildlife is optimistic about the plan but thinks the difficulty of restoring fish passage must be kept in perspective. 

"It's something that's never been done," she said. "Nobody's ever gotten fish over a high-head dam of 400 feet." 

Don Ratliff, a fisheries biologist for Portland General Electric, thinks it can be done. For five years, he and fisheries experts from federal and state agencies and the Confederated Tribes of the Warm Springs, have been working to find a way. Their research has been done as PGE and the tribes prepare a joint application to relicense the Pelton-Round Butte Project. 

PGE's federal license expires on Dec. 31. The utility and the tribes, who became partners on the project last year, expect to submit their application to the Federal Energy Regulatory Commission in June. 

As with other hydroelectric projects in the Northwest, salmon and steelhead passage will be one of the central issues. The federal agency is not saying whether it will require that fish runs be restored in the upper reaches of the river, but PGE and the tribes have worked on that assumption since the relicensing process began. 

Ratliff and his colleagues have studied water quality, resident fish, anadromous fish, habitat above the dams, predators, disease, geology and the water currents of Lake Billy Chinook. 


Trouble from the start 
Even before the Pelton-Round Butte Project was started in 1956, salmon and steelhead in the upper basin were in trouble. Historic steelhead spawning grounds in Squaw Creek near Sisters were sucked dry for irrigation each summer. Suttle Lake, home to one of two native sockeye salmon populations in Oregon, was blocked by a small dam. Another dam blocked the Crooked River near its confluence with the Deschutes. 

Yet chinook, steelhead and some sockeye returned to those streams. So when Pelton Dam and a smaller reregulating dam downstream were built in the 1950s, a trap and ladder enabled fish to pass. When Round Butte Dam was completed in 1964, a tram lifted upstream-bound adult fish from a trap at the base 400 feet upward to the reservoir. A "skimmer," a screening device on the dam's upstream side, was put in place to trap ocean-bound smolts -- young salmon --and send them downstream. 

But four years later, it became apparent the smolts weren't finding their way past the dam. In that year, the ancient salmon runs ended in the upper Deschutes basin. 


A matter of degrees 
Ratliff said finding out why smolts didn't go near the skimmer was critical to unraveling the previous failure. The answer lies in water temperature. 

The Deschutes, Metolius and Crooked rivers feed Lake Billy Chinook. The Metolius is the coldest. The Crooked is the warmest. As these waters flow into the reservoir they stratify, with the cold Metolius water resting on the bottom, the Deschutes water in the middle and the Crooked River water on the surface. 

Because the present outlet for the dam is 270 feet below the surface, the cooler Metolius and Deschutes waters drain out, but the Crooked River water stays on the surface and eddies up the Metolius arm of the reservoir. Scientists theorized migrating smolts were staying in this upper layer of water. Instead of finding the skimmer, they become lost in the Metolius arm. 

To test this theory, PGE biologists released 44,000 chinook salmon smolts in the Metolius River last year. Some fish had radio tags that enabled researchers to track them. Preliminary tracking indicates the theory is correct. 

That work, as well as computer modeling, indicates a different intake tower would change the currents in Lake Billy Chinook. The right design could draw the upper stratum of water toward the dam, leading smolts to the skimmer, Ratliff thinks. 

This is likely the option PGE and the tribes will include in their application to the federal energy commission. PGE and a committee of biologists from state and federal agencies are looking at several designs. 

The leading idea calls for drawing water from both the warm top layer and cooler lower levels and mixing them as they go through the turbines. This would alter the current while preventing big changes in the downstream water temperature. 

That alone may cost PGE and the tribes $30 million, a price they're ready to pay. 

"That's certainly in the realm of what we expected," said Julie Keil, PGE's director of hydro relicencing. "We knew when we committed to (fish passage) that it would not be inexpensive." 

But the question remains: Will it work? 

"The simple answer to that question after all those studies is maybe," said Scott Yates of Trout Unlimited who sits on the technical advisory committee that is working with the utility on fish passage. 

Government scientists on the subcommittee think a redesigned intake tower has potential to get smolts past the dam, but there are no guarantees. 

"Until the facility is actually built and operated, we won't know what the design will do with the reservoir's hydrodynamics," said Peter Lickwar of the U.S. Fish and Wildlife Service. 

Federal and state agencies, as well as environmental groups, also are adamant that PGE and the tribes' application includes a plan should the initial attempt at restoring fish passage fail. PGE's Plan B under the original license was to build a hatchery when fish passage failed. That no longer is seen as acceptable. 

"I think all of us are interested in making sure the applicant, PGE and the tribes, makes sure it continues efforts if initially it doesn't work," said Mike Gauvin, a biologist for the Warm Springs tribes. 

Keil, PGE's director of hydro relicensing, said her company is committed to following through, although she said there would be limits to how far PGE is willing to go. She did not expound on those limits. 

"We're engaged in a very difficult biological and engineering challenge right now, and I don't think anybody knows exactly what will and what will not work," Keil said. 

Stuart and Yates would like to see specific language in the new license requiring continued efforts to pass fish, especially considering the recent volatility of electrical company ownership. 

"What you have to deal with is what happens if PGE gets sold," Stuart said. "You have to build that into the license." 

Overall, however, the agency representatives and even Trout Unlimited give PGE and the tribes high marks for their efforts toward fish passage and public involvement. 

"PGE and the tribes, I think, have done a commendable job of trying to re-establish anadromy above the dams," Carlon of the National Marine Fisheries Service said. "It's a very complex problem, and they've taken it head-on."