Two dams along the Olympic Peninsula's Elwha River--once one of the richest fish-producing rivers in the U.S.--will start coming down in 2007 with help from University researcher Chris Bromley.
Saving salmon: U researcher helps bring down dams
U researcher helps bring down dams
By Deane Morrison
Thirty years ago the S'klamman tribe in Washington state began lobbying the federal government to remove two dams on the Elwha River, a river that starts in the Cascades and runs to the Pacific. Built in the first part of the 20th century, the dams provided electricity to a lumber mill, but devastated the rich native fish population, including cutthroat trout, char, steelhead, and Chinook salmon.
Now the dams are coming down. But how to take them down is the tricky part. Remove a dam too fast and huge sediment deposits will wash downstream, smothering fish eggs and burying river-bottom ecosystems. Remove a dam too slowly and the costs pile up.
Enter Chris Bromley, a graduate student in geography at the University of Nottingham, England, now doing research at the University of Minnesota. Bromley came to the University because of the visitors' program at the National Center for Earth-surface Dynamics (NCED), a National Science Foundation Science and Technology Center that receives matching support from the University of Minnesota.
To find the optimal removal schedule, Bromley built a model of a Pacific Northwest river and dam, complete with sand and running water, at the U's St. Anthony Falls Laboratory, just downstream from Minneapolis's Stone Arch Bridge. The model replicates the Elwha River and its Glines Canyon Dam, one of the two dams scheduled for removal starting in 2007.
According to the National Park Service, removing both dams and allowing the ecosystem to restore itself would open up over 70 miles of largely pristine salmon habitat. In 30 years, the present population of about 4,000 native fish would rebound to nearly 400,000.
To learn more about the Elwha River restoration project, including history and photos, visit www.nps.gov/olym/elwha/home.htm.