Barges Help Baby Salmon Traverse Dams : Wildlife: Program in the Northwest aims to help endangered species survive. Critics say it isn’t working.

LITTLE GOOSE DAM, Wash. — The accommodations are definitely steerage class. Baby salmon shoot down a pipe into the hatches of a barge for a two-day ride to safer waters.

Riding in a dark hold, they’ll be transported hundreds of miles down the Snake and Columbia rivers until they are past Bonneville Dam, near Portland, Ore., where they are released for the rest of their journey to the Pacific Ocean.

But that is better than getting lost in a reservoir, eaten by a bird, or crushed against a hydroelectric turbine.

The National Marine Fisheries Service has listed the Snake River’s sockeye salmon as an endangered species and its chinook salmon runs as threatened under the Endangered Species Act.

At a recent public hearing in Lewiston, Idaho, research scientist Michael Satterwhite said it had become clear that emphasis on using barges over the last two decades has not worked. Others share that view, contending that barges in close quarters multiply disease in fish.

But the U.S. Army Corps of Engineers contends its 16-year-old barging program is helping keep alive the embattled runs of salmon and steelhead in the Northwest.

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“Transportation is an essential tool in rebuilding threatened and endangered species,” said John McKern, a fisheries biologist for the agency in Walla Walla, Wash.

Critics contend that the number of returning salmon has not grown much, and that new measures are needed.

The Snake and Columbia rivers were once among the most productive salmon grounds, supporting returns of up to 16 million adult fish each year. These days the salmon runs are 2.5 million to 3 million fish a year, largely because of overfishing and increases in the human population.

That, in turn, brought more logging, farming, mining and industrial use of the water, plus the dams themselves, which power much of the Northwest.

Eight massive hydroelectric dams--some dating to the 1930s--have blocked the traditional migration patterns of the fish. Although most dams have some sort of bypass facilities, they have not been completely effective, and the corps contends barging is necessary.

The fish passages are expensive. The corps is to spend $217.5 million on improving fish bypass facilities along the Snake River by 1997.

Some of the money was spent to carve a shaft-like tunnel inside the Little Goose Dam.

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Little Goose Dam on the Snake River in southeastern Washington is one of the most remote places in the state, almost 30 miles north of the small town of Dayton. The river blockade provides a green and wet oasis in a parched and barren landscape.

The name is a little incongruous, especially compared with its sister dams--Lower Granite, Lower Monumental and Ice Harbor. There is nothing little about Little Goose, which is 2,600 feet long and produces 810,000 kilowatts of power.

The dam was named for an island that was submerged by the reservoir.

Here the corps has built a huge mass transit system for fish. A series of orifices and circular flumes allow 5-inch long baby salmon to move through the dam on their way to the sea. Adults use a “fish ladder”--a device to help them get over the dam--to cross back on their way to spawning grounds in Idaho.

The adults must jump nearly 100 concrete steps, each a foot tall--against the flow of cascading water--until they reach the reservoir.

The babies, meanwhile, shoot through the one-third-mile circular flume, which resembles a carnival ride, until they reach holding pens.

From the pens they are flushed into the hold of the barge and transported to an area near Portland for release.

The corps barged 16.5 million salmon in 1992, but only a comparative handful come back to their birth stream to spawn.

The reason is not known. Prime suspects include overfishing in the ocean, diseases spawned in hatcheries, predators, pollution and other factors. It is probably a combination of all of them.

The transportation program was started in 1968 at Ice Harbor Dam, using trucks instead of barges. Barging began in 1977, and now accounts for 95% of the movement.

“By transporting fish we get a lot more of them by Bonneville Dam alive,” said McKern, the corps biologist.

It is the only such program in the nation, he said.

The barging kills about 1% of each fish load. By contrast, up to 15% of the fish reaching each dam would be expected to die, McKern said.

Besides the physical barriers, the dams also raise the natural water temperature in the reservoirs by up to 4 degrees Fahrenheit. That can discourage the fish from entering. Also, the lack of river current can disorient the fish. That makes them easier prey for larger fish and birds.

Delays alone can kill fish. That’s because the salmon are racing against the physical changes that turn them into saltwater fish during the migration. If the change occurs before the fish reach the sea, they die.

Before the dams were built, fish could reach the ocean in 20 to 30 days. Now it takes 50 to 90 days to navigate through the reservoirs. The physical change occurs within about 60 days.

Barging can carry the salmon past the last dam, Bonneville, in two days, the corps said. By truck, the trip takes eight hours.

Trucks can carry about 1,750 pounds of fish, while barges hold 75,000 pounds.

But every fish is precious.

“We have sent as few as six fish downriver on a truck,” McKern said.

No one is sure how many fish die in the treacherous power turbines of the dams, although studies to determine that are under way.

The corps is studying various options for improving salmon runs.

They range from increasing the speed of the river by dumping more water from the reservoirs to building a special canal or pipeline to carry the fish to the ocean.