Great Lakes Freighter Estimated to Have Spilled 1,500 Gallons of Diesel

A U.S.-registered bulk carrier that spilled diesel fuel into Lake Michigan earlier this month is believed to have spilled approximately 1,500 gallons, the U.S. Coast Guard said on Monday.

The 630-foot-long self-unloading bulk carrier Manitowoc was approximately 1.5 nautical miles offshore of Manistee, Mich. on August 2 when it reported it was leaking diesel fuel due to a hull breach on its starboard diesel tank. The investigation into the cause of the spill is ongoing.

Prior to departing the Port of Manistee, the  vessel conducted and recorded initial tank soundings. After conducting temporary repairs, the crew again took soundings. A comparison of these two measurements revealed approximately 1,500 gallons of diesel fuel was released into Lake Michigan. The maximum potential was initially determined to be approximately 45,000 gallons.

The Coast Guard, state, local and tribal representatives have reported no impacts to the shoreline. There are no known impacts to marine wildlife and no reports of diesel in the area where the discharge occurred.

Diesel fuel spreads across the top of the water and weathers from sun, wind, and wave action. All diesel fuel is believed to have dissipated and evaporated without sinking into the water column.