A River Returns
Sunlight streaked through the leafy canopy painting the Elwha River and surrounding forest in dappled light. Two men in chest waders splashed through the swift-moving current, kicking up mushroom clouds of silt. Their eyes scanned the shallows as they make their way downstream.
John McMillan, a fish biologist with the National Oceanic and Atmospheric Administration, and Jeff Duda, a research ecologist with the U.S. Geological Survey, are here looking for steelhead and salmon nests, or redds, where fish have laid eggs. The signs are subtle but unmistakable to their trained eyes — a depression in the river bottom and disturbed gravel.
McMillan and Duda are just two of the many scientists from federal and state agencies and the local Native American tribe, who are studying the dramatic changes taking place on this river. Two massive hydroelectric dams are in the process of being removed. And these scientists are trying to understand how the largest dam removal project in the nation’s history is impacting fish.
“We’re trying to see how fast these fish recolonize after the dams have been removed,” McMillan said.
The Elwha River in western Washington State was once home to one of the biggest salmon runs in the continental United States. But in the early 1900s two dams were built on this pristine river, which today lies mostly within the protected confines of Olympic National Park. The dams provided power to the nearby town of Port Angeles and helped the frontier community grow and thrive.
But the dams were built without fish ladders and had devastating consequences for fish; salmon returning from the ocean to spawn were cut off from their natal waters. Only the lower five miles of the 45-mile river were accessible to them. Over time the dams starved those five miles of the sediment salmon need for building their nests. The diminished and degraded habitat decimated fish populations in a river once known for producing 100-pound salmon.
The Lower Elwha Klallam tribe, which has relied on the river for sustenance and its spiritual traditions for thousands of years, has been fighting for nearly 100 years to have the dams removed. In the early 1990s, Congress finally authorized dam removal as a way to help restore the river and its salmon runs. But it would take another two decades to secure funding for the $300 million project.
Dam removal began in 2011 and will connect the headwaters of the Elwha with the mouth of the river. The project is expected to be completed by 2014. One of the major challenges in removing the dams was figuring out how to deal with all the sediment stored behind the dams – enough sediment to fill 11 NFL football stadiums. To deal with the sediment, construction crews are taking the dams down gradually, piece by piece, rather than dynamiting them. Even so, the river is swollen with sediment. And the physical shape of the river is changing as the river deposits sediment along its banks.
“This place is changing every day,” Duda said. “Every time I come out there’s something new, something different.”
In five to 10 years, the sediment is expected to make its way downstream and the river will run clear once again. But for now, salmon returning to the river face some harsh conditions. Sediment can clog their gills and make it difficult to find food.
“It’s almost like you’re tearing off a Band-Aid,” Duda said. “You have to go through a little bit of pain in order to get to that final state of healing.”
On this day, McMillan and Duda walked the main channel of the Elwha River between the lower dam and the upper dam. The swift-flowing river, suffused with fine sediment from dam removal, ran a milky gray. McMillan fixed a keen eye on the clearer water near shore.
“They dug here! These are digs!”
“So you think this [is a nest] right here?” Duda said.
“This is a redd clearly,” McMillan replied. “It’s the first redd we’ve found by a steelhead in the mainstem Elwha River."
There's still a long way to go, but McMillan and Duda are hopeful that salmon and steelhead will thrive here once again.Related