Snake River dredging to start in December, Corps says
RIVERS -- Dredging in the Snake River at the ports of Lewiston and Clarkston could begin as early as mid December.
The U.S. Army Corps of Engineers' Walla Walla District says it's awarded a $6.7 million contract for maintenance dredging of the lower Snake River federal navigation channel and associated berthing areas at the the two ports near the Idaho-Washington border.
The contract was awarded to American Construction Co., Inc., of Tacoma.
The maintenance dredging is planned for the "winter in-water work window," Dec. 15 to Feb. 28, when salmonid fish are less likely to be present in the river.
The Corp worked for years and stirred up controversy before releasing the long-term, comprehensive Lower Snake River Programmatic Sediment Management Plan last week. The plan calls for reestablishing the congressionally authorized dimensions of the Lower Snake River federal navigation channel.
Dredging is the only effective short-term tool available for maintaining the federal navigation channel to authorized dimensions of 250 feet wide by 14 feet deep at minimum operating pool, Corps officials say.
The contract specifies dredging of about 400,000 cubic yards in four areas:
- the navigation lock approach at Ice Harbor Dam;
- confluence of the Snake and Clearwater rivers;
- Port of Lewiston berthing area; and
- Port of Clarkston berthing area.
The Corps plans to use the dredged material to create shallow-water habitat for juvenile salmon at Snake River mile 116, located just upstream of Knoxway Canyon and 23 miles downstream of Clarkston.
