After saying goodbye to the last saltie of the season on Saturday, Dec. 28, 2024, the Port of Duluth-Superior is getting ready for the end of laker season as the Soo Locks closes on Jan. 15. Laker season is longer than saltie season because those ships traverse the Great Lakes and are not ocean-going ships.

"The Soo Locks' MacArthur Lock closed for the Navigation Season to conduct seasonal repairs and maintenance on Dec. 16, 2024," noted the USACE Detroit District on their website. "The Poe Lock will remain open until Jan. 15, 2025, or until commercial traffic ceases, whichever occurs first."

"The Soo Project Office (SPO) is a multi-disciplinary team of teams that perform and oversee critical inspections, repairs and maintenance during the annual non-navigation closure period, often referred to as winter work," said LeighAnn Ryckeghem, SPO operations manager. "With both the MacArthur and Poe locks being well beyond intended service life, it's imperative that these national assets continue to be strategically managed and winter work activities be optimized to ensure operational reliability until the New Lock at the Soo is put into service."

The Soo Locks will remain closed through 12:01 a.m. March 25, 2025, to perform seasonal critical maintenance. Federal regulation (33 CFR 207.440) establishes the operating season based on the feasibility of vessels operating during typical Great Lakes ice conditions.

More than 4,500 vessels, carrying up to 80 million tons of cargo, maneuver through the Soo Locks annually. Iron ore, coal, wheat and limestone are the most frequently carried commodities.

The U.S. Army Corps of Engineers, Detroit District, maintains a navigation system including 81 harbors and channels joining lakes Superior, Michigan, Huron, St. Clair and Erie.

PORT OF DULUTH-SUPERIOR PREPARES FOR HIBERNATION

David Sauer, Schauer Photo Images, told DTN the accompanying photo was taken on Saturday, Jan. 11. "On the left is the Atlantic Huron with the Canada Steamship Company here for winter layup. On the right is the tug/barge Presque Isle (Duluth-based thousand-foot tug-barge)at the port for some mechanical work before shifting to the CN (Canadian National) dock in Duluth to take on a partial load of ore before returning to this slip for winter layup (the partial load helps keep the combination low in the water and relieves stress on the coupling between tug and barge). In the harbor is the arriving 1000-footer James R. Barker (Interlake Steamship Company) to load ore at CN, its last trip of the season."

"Winter layup is showtime for the region's skilled tradespeople, who perform millions of dollars in maintenance work and upgrades to prepare these vessels for the upcoming navigation season, which will begin when the Soo Locks re-open on March 25," Jayson Hron, director of communication and marketing, Duluth Seaway Port Authority, told DTN.

Here are the ships wintering in Duluth-Superior and where they are docked:

Located at the westernmost tip of Lake Superior, the Port of Duluth-Superior is North America's farthest-inland freshwater seaport. A remarkable 9-mile natural breakwater shelters the port's 49 miles of harbor frontage. Twenty privately owned bulk cargo docks and an award-winning general cargo terminal populate the working waterfront, along with a marine fueling depot, a shipyard with dry docks, multiple tug and barge services, plus an intermodal cargo terminal.

Video of American Spirit arriving in Duluth to load iron ore pellets and Presque Isle arrival for winter layup on the chilly morning of Jan. 10.: https://youtu.be/…

Mary Kennedy can be reached at Mary.Kennedy@dtn.com

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