RIVERS --  The U.S. Army Corps of Engineers has announced it will proceed with a controversial plan to dredge sediment in the lower Snake River on or about Jan. 12, as a result of a favorable ruling from the U.S. District Court for the Western District of Washington in Seattle.

In a lawsuit filed by a coalition of environmental groups and the Nez Perce Tribe (Plaintiffs) the Court denied  the Plaintiffs request for a preliminary injunction that would have stopped needed maintenance of the federal navigation channel and related port berthing areas.

The Inland Port and Navigation Group and the Columbia Snake River Irrigators Association intervened in the lawsuit in support of the Corps. The Corps itself made a bold bet it would win the suit.

The Corps will dredge this year in accordance with its comprehensive Programmatic Sediment Management Plan during the annual winter in-water work window when salmonid fish are less likely to be present in the river.

"There is a current immediate need to reestablish the federal navigation channel at congressionally authorized dimensions," said Lt. Col. Timothy Vail, Walla Walla District Commander. "After consideration of potential alternatives, we determined that dredging is the only effective short-term method available for doing so once sediment has accumulated to the point of interfering with navigation."

Congress directed establishment of the navigation channel in the Lower Snake River at 250 feet wide by 14 feet deep at Minimum Operating Pool (MOP). The Corps of Engineers is responsible for maintaining the channel at those dimensions, he said.  

Maintenance dredging last occurred in the lower Snake River navigation channel in the winter of 2005-2006. Sediment accumulation has since encroached on certain areas of the federal navigation channel and port berthing areas.