Dam Removal Spawns Stunning Changes in Elwha River
Dams that have stood on the Elwha River on Washington's Olympic Peninsula for nearly a century are finally tumbling down, with the last slabs of concrete expected to fall this September, but demolition crews and scientists are already noticing nature reclaiming its territory, the Associated Press reported.
Lots of sediment previously trapped behind two hydroelectric dams has flown downstream, completely reshaping the river's mouth and creating new habitats for marine creatures not seen there for years.
After the first dam was torn down in 2012, ocean migrating fish like the Chinook salmon and steelhead were seen swimming far up the river to waters previously blocked by the Elwha Dam.
Now, with these fish free to roam, they are acting as a fertilizer for the ecosystem by providing marine nutrients to river otters and other wildlife.
Demolition crews said they will start removing the remaining 30 feet of the Glines Canyon Dam once the river flow slows down. By the end of 2014, it is expected that the Elwha River will flow dam-free.
Besides the return of some marine life, stunning changes have already taken place at the river's mouth just three years into dam removal. The estuary has been pushed out a quarter mile, and a once rocky, cobblestone scene is now sandy beach.
"New estuary is literally being created. It's wild to watch," Anne Shaffer, marine biologist with the Coastal Watershed Institute in Port Angeles, Wash. told the Associated Press. "Fish are using this freshly formed habitat, and they're using it with such abundance."
"I was surprised by a lot of things, but I was stunned by how fast the estuary has expanded," added Robert Elofson, river restoration director with the Lower Elwha Klallam Tribe. The tribe partnered with the National Park Service in financing this $325 million river-restoration project.
Marine creatures such as eulachon, or candlefish, and Dungeness crab have been documented in the estuary for the first time in decades.
All these changes are occurring and according to biologists, only 40 to 50 percent of expected sediment has flown down river so far. All this sediment does create for some muddy waters, but it seems that the fish are coping well, swimming as far as they must so that they can spawn in clearer waters.
At the project's end, the Elwha River is expected to flow dam-free from the Olympic Mountains to the Strait of Juan de Fuca, about 80 miles west of Seattle.