Us army corps of engineers walla walla district is issuing a construction solicitation for a project titled navigation channel maintenance 2022. The work will take place in the lower granite dam pool at the confluence of the snake and clearwater rivers near Lewiston, Idaho, Washington, additional dredge work is located on the lower snake river just downstream of the ice harbor dam in the McNary dam pool.

Us army corps of engineers proposes to perform maintenance dredging in 2022/2023 to meet the immediate need of providing a 14-foot navigation channel depth as measured at the minimum operating pool at four locations in the lower snake river and lower clearwater river in Washington and Idaho including two access channels between the port of Clarkston docks and the federal navigation channel. The 14-foot minimum depth is the depth required to safely pass large boats and barges the corps is authorized by the flood control act of 1952 to maintain a 14-foot deep channel in order to ensure a depth of 14 feet, the corps would dredge to a depth up to 16 feet this 16-foot depth includes one foot of advanced measures and one foot to account for mechanical inaccuracies of the dredging equipment.