LEWISTON, Idaho -

The U.S. Army Corps of Engineers has released its final plan and environmental impact statement for manage sediment accumulation in the lower Snake and Clearwater rivers in northern Idaho.

The plan calls for dredging the navigation channel of the lower Snake River at the confluence of the Clearwater River as early as between Dec. 15 and Feb. 28 this winter.

The Lewiston Tribune reports that the agency has been working on the plan since 2005. The final plan is more than 3,900 pages and cost $16 million to prepare.

The plan also identifies a number of other tools the agency can use to manage sediment over the next 20 years.

A 30-day public comment period on the plan will begin next Friday.