Navy seeks 10-year permit to dredge portions of the Kennebec River

The Department of the Navy in Bath is seeking a 10-year permit from the U.S. Army Corps of Engineers to dredge portions of the Kennebec River from Bath to Phippsburg to allow the passage of Bath-built destroyers.

The Navy expects maintenance dredging will be needed every three years, according to a news release.

The first dredging would happen during the winter of 2019-2020 and would move 80,000 cubic yards — roughly the volume of 20 Olympic swimming pools — of sand and sediment from the bottom of the Kennebec River between Bath and Phippsburg, particularly in shoal-prone areas. Shoals are large wave-like formations of sand that accumulate on the bottom of the river.

Up to 50,000 cubic yards will be removed from Doubling Point and dumped in the river near Bluff Head to make the area around Doubling Point 31 feet deep. At the river mouth, up to 20,000 cubic yards will be taken until the river is 29 feet deep and disposed of near Jackknife Ledge. Both disposal sites have been used repeatedly in previous dredging projects.

The dredging process takes approximately a month to complete, using a hopper dredge and/or a mechanical dredge. The U.S. Army Corps of Engineers did not disclose how much the process costs.

These maintenance dredges ensure the Kennebec is deep enough so the military vessels made by Bath Iron Works can move downriver to open ocean. BIW’s most recently christened Arleigh Burke-class destroyer, the future USS Daniel Inouye, will leave the Bath shipyard in 2020 for Pearl Harbor, Hawaii.