CHINOOK, Wash. - Large numbers of salmon may soon make their way into a tidal wetland that’s been closed to migrating fish on the Columbia River for more than a century.
The wetland near Chinook, Wash., is the type of habitat that is vital to the survival of migrating juvenile salmon and is clearly marked on the historic maps of explorers Lewis and Clark.
Since the 1890’s, railroad tracks and a highway, now US 101, disconnected the river and tides from the 96-acre marsh. During construction, crews installed an enormous new culvert with a natural stream bottom that will once again connect the river to the wetland.
Wednesday, Feb. 16, crews removed a large cofferdam. The temporary structure kept water from entering the new culvert during construction. Once the dam is removed, the Columbia River tides will flow into the marsh for the first time in more than 100 years.
Fisheries biologists have determined shallow tidal wetlands offer juvenile salmon a refuge from predators and a place to feed and transition from fresh to saltwater.
The juvenile salmon, also called smolts, will spend as long as 60 days resting and foraging in wetlands as they prepare for their long ocean migrations.
Ecologists say the re-opening of the tidal wetland is important to Columbia River fisheries since approximately 65 percent of the river’s historic estuary wetlands no longer exists. Other projects aim to restore hundreds of acres more habitat throughout the estuary.
Environmental experts from the Columbia River Estuary Study Task Force, or CREST, are leading the project with the Bonneville Power Administration providing project oversight plus a large portion of the $1.2 million needed for construction.
WHO: The Bonneville Power Administration and CREST
WHAT: Re-opening an historic tidal wetland to migrating salmon (video and images available upon request)
WHERE: Highway 101 near Fort Columbia, MP 3.24 US 101, south of Chinook, Wash.
BPA is a not-for-profit federal electric utility that operates a high-voltage transmission grid comprising more than 15,000 miles of lines and associated substations in Washington, Oregon, Idaho and Montana. It also markets more than a third of the electricity consumed in the Pacific Northwest. The power is produced at 31 federal dams operated by the U.S. Army Corps of Engineers and Bureau of Reclamation and one nuclear plant in the Northwest and is sold to more than 140 Northwest utilities. BPA purchases power from seven wind projects and has more than 3,300 megawatts of wind interconnected to its transmission system.