Dams to go down; salmon to go up
The Associated Press
PORT ANGELES, WA - 8/18/02 - Big changes are coming to the Elwha River and the fish that live in it. By 2007, the two dams that contain the river will be gone - opening its upper reaches to salmon once again.
Biologists are scrambling to complete a census of the fish there now, so those changes will be better understood.
Last week, a dozen researchers from the Lower Elwha Klallam tribe and from local and federal agencies used snorkeling gear and dry suits to comb the lower reaches of the river and count juvenile and adult salmon.
They'll be documenting salmon numbers throughout the demolition of the Elwha and Glines Canyon dams, scheduled to begin in 2005 and end in 2007, to assess the impact of the undertaking.
"This is our first attempt to quantify the number of salmon, particularly juvenile salmon, in the main stem of the Elwha River," said Mike McHenry, the tribe's habitat manager.
Biologists have worked to restore salmon habitat on the lower five miles of the Elwha River - the stretch below the Elwha dam - since 1994, when the tribe began studying river side channels.
In 1999, using a $250,000 grant from what would become the Salmon Recovery Funding Board, the Lower Elwha Klallam began constructing logjams in the lower river to improve salmon habitat. Logjams rarely occur naturally. Logging and increased channelization along the river banks - combined with the dams blocking downstream flows of wood - have diminished the log supply.
In the past three years, 11 large jams have been built, providing shelter and shade for young salmon and reining in the river flows in winter. Pools formed by the logjams aid photosynthesis, providing more food for fish.
First-year project data indicate the effort achieved what tribal biologists hoped it would.
"There were significantly larger numbers of fish of all species in those habitat areas," McHenry said.
Biologists find the logjams also provide an ideal rearing ground for juvenile salmon.
The hydroelectric dams have created other problems for salmon. Increased temperatures in the reservoirs - Lake Mills and Lake Aldwell - generate bacteria. The dams also block gravel flow downstream, leaving bowling-ball-size rocks that salmon cannot push aside for nesting.
All that may change when the dams are removed.
"We think a lot of the problems associated with dams right now will go away rather quickly," McHenry said.
Historically, the river produced about 390,000 salmon annually, said Brian Winter, Elwha project manager with the National Park Service. Now, about 10,000 to 12,000 salmon return each year - and most are hatchery-supported, Winter said.
The river once supported all species of Pacific salmon and was dominated by pinks. Now, coho and chinooks are most abundant, with pink and chum populations marginal, McHenry said.
For the first 10 years after the dams are removed, biologists will plant juvenile salmon from hatcheries, flying them by helicopter to the upper watershed to accelerate natural migration.
They will be deposited in pristine waters protected by Olympic National Park, then make their way out to sea and return to spawn, Winter said.
The river is expected to return to its natural state 30 years after dam removal, but Winter expects salmon habitat "will be booming" after 20 years.
"Every piece of this project is proven," Winter said. "It's just never been put together like this before."
Snorkeling fish counts will be conducted annually. While this year's count focuses on the stretch below the Elwha Dam, future counts will be taken in the middle and upper regions, now dominated by trout.
"It's not anything near what the ecosystem was or what we hope it will become," McHenry said. "That's something that's unique about the Elwha. We can restore this river."
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