Someday soon, the upper reaches of Washington State’s Stillaguamish River will once again be brimming with salmon and steelhead trout. And it will happen with the help of GBI.
The U.S. Forest Service and Stillaguamish Tribe of Indians initiated the Gold Basin Habitat Restoration Project to improve the habitat of salmonid species in the Stillaguamish River Basin by reducing the delivery of fine sediment into one of the river’s two forks, the South Fork. To accomplish this, a new channel is now being excavated to move the river away from the Gold Basin landslide, which is located along the South Fork. The landslide has three lobes that have continuously deposited sediment into the river, and as a result, salmon and steelhead have not returned to the area to spawn. By excavating a new channel and relocating the river, all of the landslide material will flow into the soon-to-be-dry former channel.
GBI started working on the project in May of 2021. It is expected to complete in mid-October.
The scope of work includes the clearing of 14 acres of large second-growth timber, along with 215,000 CY of excavation and embankment to create the new 250-foot-wide channel and fill the existing channel. It also includes the construction of a 1,100-LF live crib structure, a 1,000-LF meander log jam, and a 1,200-LF large wood bank jam, as well as the installation of five timber crib check dams totaling 1,020 LF, and site restoration and planting.
GBI has completed its share of river restoration projects over the years, but this is the first that has involved the construction and installation of a larger-than-usual live crib. Crews had to partially assemble, set, and backfill each section of the live crib into excavated footings before they could be completed. Additionally, logging shovels and large excavators were used to lift and set the assembled portions in the footings before each assembly could be completed. This required stacking, bolting, and backfilling additional timbers to a height of 25 feet.
And there’s another unique feature: the newly excavated channel is located on the river’s access side, and when its construction is complete, water will be diverted into the new channel and a temporary bridge will be used to access the opposite-side riverbank in order to finish the project.
A local logging contractor was hired to complete the clearing and grubbing, and per their contract, all timber would be left on-site. Given the volume of wood generated, GBI worked with the Stillaguamish Tribe and the project engineer to utilize the on-site timber in the design elements of the wood structures. This has reduced the costs of importing, handling, and processing off-site timber and will ultimately save the Stillaguamish Tribe hundreds of thousands of dollars.
GBI Washington Region Senior Manager Ron Jordan has worked closely with the Stillaguamish Tribe since the project went out to public bid in January of 2018. After permitting issues led to delays and the project design changed several times, efforts were made to assist the Tribe in moving forward with the project while keeping the costs within their budget. Today, under the direction of Ron and GBI Washington Region Superintendents Dave Swansen and Jason Landon, construction is fully underway. What was initially slated to be a two-season project will now be completed in one, thanks to the hard work and dedication of GBI’s crews. Their efforts have not gone unnoticed by Stillaguamish Tribe members, who continue to express their sincere gratitude to GBI for a job well done so far.