By Mark Stayton, August 26, 2014, Go Skagit
Dredging to remove sediment on the south end of the Swinomish Channel is scheduled to begin in late September and finish in the fourth week of December, according to a Port of Skagit news release.
The U.S. Army Corps of Engineers issued a contract to American Construction for $820,750 in July to complete the project, the news release stated.
John Hicks, chief of navigation for the Corps’ Seattle office, said the project will remove sediment around a long jetty that shields the south entrance of the channel from debris flowing from the north fork of the Skagit River.
Hicks said the holes in the jetty — occurring both from natural degradation and built in for salmon migration — have allowed sediment to build up in the entrance of the channel near Goat Island.
Hicks said the design of the jetty will be reconsidered and a rebuild could be necessary to improve it.
A $2.68 million project to dredge the channel was last completed in January 2013, removing 215,000 cubic yards of sediment from the south end of the channel.
The project’s goal was to provide a depth of 12 feet at zero tide, said John Pell, Corps project manager.
Sara Young, Port director of planning and facilities, said the decision to dredge the channel was driven by a bathymetric survey of the channel completed by the Corps in 2013. She said the Port and other local partners strive to have the channel dredged every three years.
The south end of the channel accumulates sediment at an average rate of 1.5 feet per year, Young said, though that varies greatly across the width and length of the waterway.
Lobbying efforts to dredge the channel are led by the ports of Skagit and Anacortes, the Swinomish and Upper Skagit tribes, Skagit County, the town of La Conner, Skagit County and the Pacific Northwest Waterways Association, Young said.
A 2010 Port of Skagit-commissioned economic survey found marine-related businesses and boaters on the channel generate about $92.6 million in business revenue annually, directly supporting 521 jobs.