By Kevin Hanson, The Courier-Herald
A project now under way along the White River will take months to complete, cost more than $2 million and temporarily send the river curving away from its traditional banks.
And, after the work is done and the money spent, the riverbed will be a friendlier place for migrating salmon.
The project, undertaken by the city of Tacoma's water division, has already made a great impact on the south side of the river, just upstream of the bridge between Enumclaw and Buckley. Trees have been removed and a stretch of riverbank scoured clean; a similar fate awaits the north shoreline.
The goal of the river project is to replace a 750-foot section of a water line that originates at the Green River, about a mile downstream of the Howard Hansen Dam, and travels through Enumclaw, Buckley, Bonney Lake and Sumner, before feeding the city of Tacoma's water needs. The supply line, visible in many places and buried in others, is Tacoma's primary water source, said Glen George, manager for the White River project.
The supply line was built perhaps 75 years ago, George said, and - when crews buried pipe in the riverbed - it was installed too shallow. The river kept excavating around the water line, so Tacoma built a concrete dam in the river to protect its investment. Concrete was added in the 1920s, '30s and '40s, George said, until it reached six feet tall. In the 1950s, a fish ladder was installed to help fish navigate their way past the artificial dam.
"That ladder no longer functions adequately at all," George said, adding that it's believed fish are damaged as they scrape their way over the concrete.
So, Tacoma is tearing out the concrete dam and fish ladder, and installing a new water line, this time 18 to 20 feet below the river bottom. To dig a trench that deep, George explained, workers will have to start 250 feet on either side of the river; along with the 250-foot river span, that accounts for the 750-foot project.
To install the new line, "we'll have to move the river out of the way temporarily," George said. A 500-foot bypass channel will be built on the river's south side and will channel water around the work site.
George said the city of Tacoma has had the White River project on the drawing board for 14 years, but anything involving salmon is a sensitive issue that has to work its way through a variety of governmental entities. "We really couldn't reach consensus that the dam needed to be removed," he said, adding that the political landscape shifted a few years ago, making the project a reality.
Involved in the decision-making process, George said, have been the U.S. Department of Fish and Wildlife, Army Corps of Engineers, state Department of Fish and Wildlife, state Department of Ecology, state Department of Natural Resources, both King and Pierce counties, the city of Buckley and both the Muckleshoot and Puyallup tribes.
George said work crews have a six-week window where they can work in the river, from mid-August through the end of September. There will be a couple of months spent on riverbank restoration, he said, noting the entire project should be wrapped up by mid-December.
The total project cost has been pegged at $2.1 million, and has been aided by a $940,000 grant from the state's Salmon Recovery Funding Board. Tacoma's water division will pick up the remainder of the tab.
Kevin Hanson can be reached at khanson@courierherald.com
