At 1312 local time on May 27, 2016, the US-flagged lake freighter (laker) Roger Blough ran aground near the Gros Cap Reefs Light off Sault Sainte Marie, Ontario, Canada. The grounding occurred as the vessel entered the Birch Point Course section of the St. Marys River federal navigation channel from Whitefish Bay in eastern Lake Superior. There were no injuries and no pollution reported. The vessel sustained $4.5 million in damage to its hull and cargo system.

​​The probable cause of the grounding of the lake freighter Roger Blough was the second mate’s failure to use all navigational resources to determine the ship’s position as it approached shallow water near Gros Cap Reefs. Contributing to the accident was inadequate monitoring of the vessel by Vessel ​Traffic Service (VTS) St. Marys River