US Tariffs Spark Crisis in Great Lakes Shipping Industry

The American Century, a 1,000-foot-long bulk carrier built in 1981 in Sturgeon Bay, Wisconsin, is a symbol of the Great Lakes shipping industry's reliance on trade with Canada. The vessel, which runs on four General Motors Co. diesel engines, has set records for coal payloads and depends on a regional economy that moved in lockstep with Canada. However, US tariffs have disrupted trade in iron ore, causing a rift between Ottawa and Washington that threatens lasting damage to supply chains across land and water.

The Duluth Seaway Port Authority reported a 23% decline in vessel traffic at the Port of Duluth-Superior through August, with visits by US-flagged ships falling about 19% and arrivals by Canadian carriers sinking 37%. Coal volumes totaled 4.7 million tons in 2025 and are on track to reach just 500,000 tons this year, the lowest level since 1973.

Ian Hamilton, president and CEO of the Hamilton-Oshawa Port Authority, said that 'over decades and decades of time, the Great Lakes, the states and the provinces have become a hugely integrated, the third-largest economy in the world if it was a country,' with $6 trillion in economic activity across the region.