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Snake River Dam Issue
by Robert McClure
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As federal officials approach a key decision on rescuing battered Snake River salmon runs, two new scientific analyses are bolstering arguments for breaching four Eastern Washington dams to let the river run free.
But salmon in the Snake-Columbia river system are returning to spawn in the largest numbers in decades, prompting a few scientists to question whether cyclic climate changes that affect salmon survival in the ocean have more influence on the fish. Some question whether it's necessary to abandon the dams, at least for now.
"This is an ongoing, contentious national problem, because there are no simple answers," said Jim Anderson, a University of Washington oceanography. "There are not even any simple questions."
The National Marine Fisheries Service was to decide on dam breaching this week but delayed a ruling until late June, in part because of technical problems but also "because it's hard," said Will Stelle, regional manager of the Fisheries Service.
The Snake's wild coho are gone, and the sockeye have virtually disappeared. Scientists largely agree that punching holes in the dams' earthen flanks -- "breaching" them -- would help save the remaining salmon.
No longer would some juvenile fish migrating to see have to swim a gantlet of spinning metal blades, poisonous gasses and water pressure changes that can blow their eyes from their sockets.
No longer would some young salmon be sucked into collection systems to be loaded onto barges to bypass the dams. Some are shot down quarter-mile tubes with two 90-degree bends at 30 feet per second. Most later die.
In addition to helping young salmon migrate to sea, breaching the dams would remove some impediments for adult salmon returning to spawn in their home streams.
Yet breaching isn't free. The cost of moving wheat, paper and other goods would rise because barges could no longer navigate 140 miles of river; irrigation water for 13 large farms near Pasco would have to be replaced, and electric bills would increase $2 to $5 per month as hydroelectric turbines stop spinning.
Reports call for fast action
Two recent scientific analyses paint a stark portrait of likely extermination of at least one more Snake River stock unless there is fast, sweeping action.
A study by Fisheries Service scientists suggests that saving the most endangered of the Snake River salmon -- chinook that return to spawn in the spring and summer -- requires more than dam breaching.
"Although there is some evidence that dam breaching is necessary for mitigating the extinction risk faced by the Snake River spring/summer chinook salmon (especially given the lack of evidence that needed improvements can be made by non-breaching management options), it is highly unlikely that breaching alone will recover these populations," the Fisheries Service scientists wrote.
Fish biologists working for Idaho and Oregon, the U.S. Fish and Wildlife Service, Indian tribes and the Columbia Basin Fish and Wildlife Authority, meanwhile, called the Fisheries Service's analysis inaccurate and too optimistic. They said in even stronger terms that the dams must be breached.
"No matter how they slice it and dice it, they still come up with that conclusion (favoring dam breaching), and every time they do it, the conclusion gets a little more adamant," said Gretchen Oosterhout, a consultant on institutional decision-making working with the latter group of scientists.
The course most likely to be recommended next month is a Clinton administration plan to leave the dams in place for five to 10 years while attempting to make progress through other means.
"This is not 'Don't do anything for five years,'" said Stelle, of the Fisheries Service. "It's an aggressive set of efforts across the board . . . emphasizing the need for some very substantial improvements."
The Fisheries Service is considering a wide range of enforceable targets for salmon recovery. For example, it might recommend breaching unless a set number of miles of streamside are restored or so many gallons of water are allowed to flow in the streams instead of being siphoned off for farming, drinking water and other human needs. A measurable increase in salmon returning to spawn is a likely requirement.
Congress has final say on the fate of the dams, and is currently hostile to breaching. A delay by the Fisheries Service would keep the idea on the table.
Meanwhile, federal agencies would move forward with preliminaries to dam-breaching, including development of an aid package to buffer the economic effect.
Dam-dependent businesses would just as soon see the whole idea of breaching jettisoned for good, said Bruce Lovelin, who lobbies for those businesses as director of the Columbia River Alliance.
Lovelin is leery of the "performance standards" the Fisheries Service is considering.
"If it's something unattainable, then it's clearly a setup for leveraging the system" to mandate dam breaching, he said.
Environmentalists also are focusing on the Fisheries Service plan.
"Is it an off-ramp or an on-ramp to dam removal?" asked Rob Masonis of American Rivers, an environmental group. He wants to know "whether they're postponing a decision on dam removal by five or 10 years or whether they're calling for removal at a date-certain unless they're able to miraculously turn things around."
They say that's too long to wait.
Oosterhout, the decision scientist, notes that the two recent scientific analyses followed a separate effort involving dozens of Northwest scientists. That exhaustive effort -- the five-year, $8 million Process for Analyzing and Testing Hypotheses, or PATH -- favored dam breaching. Several of the members were authors of the recent analysis that called most strongly for dam breaching.
"Every time they reanalyze this question, the answer gets firmer and louder," Oosterhout said. "Since the politicians are saying they really want science to drive the decision, you would think that would be the end of the story."
Climate could be to blame
Other scientists, though, highlight a key unknown: How much of the salmon's decline since the Snake dams were finished in 1975 is because of the dams, and how much is because of something else?
In recent years, research has suggested that conditions affecting salmon in the ocean worsened at about the time the Snake Dams were finished.
"When they put in the dams, they conducted a really unfortunate experiment in that they put them in at the same time ocean conditions turned worse," said Michelle McClure, a Fisheries Service biologist. "Some people want to blame all the declines of the last two decades on the dams. Some want to blame all the declines of the last two decades on ocean conditions. The truth lies somewhere in between."
It appears that, about 1977, a storm-forming weather phenomenon known as the Aleutian Low shifted southward and intensified. This was accompanied by changes in wind patterns and a warming of the surface of the northeast Pacific Ocean.
Combined with a poorly understood link to changes in ocean conditions, this apparently led to a reduction in the amount of plankton available for salmon to eat, and encouraged mackerel and other warm-water salmon predators to swim north, researchers say.
Anderson, the UW professor, argues that both recent studies bolstering the case for dam-breaching are wrong. Anderson, whose work is funded by the Bonneville Power Administration, says the reports ignore the fact that ocean conditions have grown more favorable to salmon in the past year or so.
By Wednesday, 172,976 salmon had returned to the Snake-Columbia river system, nearly three times the average of the past 10 years. (Most are fish from hatcheries, not the wild fish federal agencies are trying to save. But it's likely that numbers of wild fish are increasing roughly in proportion to the others.)
But dam-breaching proponents point out that, no matter how many fish might return to spawn in any single year, the percentage of those migrating to sea in the first place also is important. Government scientists say 2 percent to 6 percent need to return and reproduce, on average, to maintain a stable population. The number has hovered well below
2 percent for many years. And the overall population has plummeted.
Anderson also argues that the success of barging salmon around dams has been underestimated.
Then there's the question of whether dam breaching alone would do the trick. The Fisheries Service scientists say no.
"If removing the dams gives us a 10 percent change in survival, but to recover the stocks we need a 500 percent increase, what's the point in removing the dams?" Anderson asks.
Although the number of salmon returning to spawn appears to be rebounding because of the climate shift, it's also likely that conditions will change back, Anderson said.
Meanwhile, human population continues to grow. If people keep harming streams and streamsides the salmon depend on, and if the climate does shift back to one less favorable to salmon, Anderson said, "These fish might just be unsavable."
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