An unmanned tug operated by the U.S. Army Corps of Engineers sank while it was being towed on the St. Mary’s River near Sault Ste. Marie, Mich.
The tug Hammond Bay was being towed by the tug Donald L. Billmaier along with three barges from Duluth to Sault Ste. Marie at about 0330 on July 1. While preparing to lock through the Soo Locks the crew lost sight of Hammond Bay, which is used as a tender for Army Corps work barges.
After an initial search the 59-year-old tug could not be located and the river was closed to commercial traffic. The next morning Hammond Bay was found resting in 37 feet of water near lighted buoy 25. Because it had 27 feet of overhead clearance, the sunken tug did not impede river traffic.
The vessel had 200 gallons of diesel fuel and 15 gallons of oil on board when it sank. The U.S. Coast Guard conducted an initial investigation.
“The Coast Guard did not find any human neglect so we turned the investigation over to the Army Corps to determine why their tug sank,” said Lt. j.g. Derek Puzzuoli.
The Army Corps has not released the results of its investigation, according to Lynn M. Rose, spokeswoman for the Detroit District.
The Coast Guard established a 500-foot safety zone around the tug during the salvage operations. The Corps used the crane barge Harvey with assistance from the derrick barge Nicolet and derrick barge Howard J. Schwartz to lift the vessel back to the surface. The tug was raised to the surface using divers to rig the vessel and then it was pumped out to refloat it.
Early reports indicated the vessel, built in 1954 and used originally by the U.S. Army, did not suffer extensive damage, with all windows intact. The tug was returned to service July 24 and worked around Sault Ste. Marie over the summer, Rose said.
It cost about $50,000 to return the vessel to service, including flushing all fluids, drying electronics and the steering area and disassembling and reassembling the engine, Rose said.
Rose noted the electronics are working but there’s the possibility of long-term damage from being submerged.