The U.S. Coast Guard is working to identify the cause of a hull fracture on the Canada-flagged bulk carrier Michipicoten that occurred while the vessel was underway in Lake Superior.
Crew aboard the 72-year-old ship issued a mayday call to the U.S. Coast Guard at about 0553 on June 8 reporting hearing a loud bang while transiting roughly 35 miles southwest of Isle Royale. The crew also said the ship was flooding at a rate of 144,000 gallons per hour.
Multiple vessels ultimately responded to the stricken bulker, which sailed into Thunder Bay, Ontario, with a pronounced list. Divers later discovered a 13-foot-long hull fracture running longitudinally along the bottom between a quarter- and half-inch wide.
The incident generated tremendous media attention across the Great Lakes, particularly after the U.S. Coast Guard suggested the ship potentially struck a submerged object. Water depths in that section of Lake Superior exceed 1,000 feet in some places, raising questions about what, exactly, the ship might have struck.
The U.S. Coast Guard continues to investigate the incident and has not identified a cause. Following a dive assessment in Thunder Bay, the service expressed doubts that the fracture stemmed from contact with an underwater object.
“The specific cause of the damage is still under investigation, but divers did not find evidence consistent with striking an underwater object,” said Lt. Joseph Snyder, a spokesperson for the U.S. Coast Guard Sector Northern Great Lakes.
Whatever happened, it occurred as Michipicoten sailed from Two Harbors, Minn., northeast of Duluth, to Sault Ste. Marie, Mich., with 22 crewmembers and taconite in its holds. Its crew reported to the Coast Guard that “they heard a loud noise as though they hit something and were taking on 300 tons of water per 30 minutes,” Snyder said.
Flooding into a starboard ballast tank and later a centerline void space caused the ship to list as much as 15 degrees, he said. That list decreased to about 5 degrees by the time the ship reached Thunder Bay.
Multiple vessels responded to the ship’s distress call, including a 45-foot U.S. Coast Guard response boat from Bayfield, Wis., and a helicopter from Air Station Traverse City. The U.S.-flagged Great Lakes freighter Edwin H. Gott diverted to Michipicoten and remained nearby as it chugged toward Thunder Bay. A Canadian Coast Guard ship and the U.S. Coast Guard response vessel escorted the bulker into berth.
Eleven of Michipicoten’s crew disembarked onto the U.S. Coast Guard response boat and a separate National Park Service vessel from Isle Royale, Snyder said. Eleven others remained on the ship for the transit into Thunder Bay.
Michipicoten discharged its taconite cargo before sailing to Fraser Shipyards in Superior, Wis., for permanent repairs. As of late June, it remained at the shipyard, according to AIS data.
RAND Logistics of Williamsville, N.Y., operates Michipicoten in its fleet of 14 U.S.- and Canada-flagged freighters sailing on the Great Lakes. The company did not respond to an inquiry about the incident.