The Poe Lock, part of the Soo Locks in Sault Ste. Marie, will open to marine traffic early March 25, marking the start of the 2026 Great Lakes shipping season. (Photo provided by the U.S. Army Corps of Engineers)

SAULT STE. MARIE – The Poe Lock, part of the Soo Locks in Sault Ste. Marie, will open to marine traffic at 12:01 a.m. Eastern time March 25, marking the start of the 2026 Great Lakes shipping season, the U.S. Army Corps of Engineers announced Tuesday.

Federal regulation establishes the operating season based on the feasibility of vessels operating during typical Great Lakes ice conditions, according to a news release Tuesday from the Corps’ Detroit District.

“Our winter closure period is essential for conducting critical inspections, repairs and maintenance on our aging infrastructure,” Soo Locks Operations Manager LeighAnn Ryckeghem said in the release. “The reliability of Great Lakes navigation and the momentum of the American industrial supply chain depend on getting this work done.”

The locks officially closed for the 10-week-long winter shutdown after the last vessel of the season transited the Poe Lock on Jan. 15.

Maintenance work on the Poe Lock included underfloor cleanout and manhole inspection, a five-year periodic inspection, Gate 1 repairs, Gate 4 lifting lug installation, Gate 2 concrete repairs and applying an experimental ice shedding coating. Additional work was simultaneously done on the MacArthur Lock.

“Project staff started work well in advance of the navigational shutdown in planning and resourcing projects, getting contract actions in place, and sequencing work to optimize the short time available for critical maintenance and repairs,” Maintenance Branch Chief Tim Bartlett said in the news release. “Due to the hard work of our crews during a near-record snowfall season, we’ve been able to accomplish the required work on time.”

The park and viewing platform will open at 11:30 p.m. March 24 to allow visitors to welcome the first ship from the viewing platform. The visitor center will also host its annual open house for the public from 9 a.m. until 3 p.m. Eastern time March 25.

“We welcome visitors into the park for the 2026 Soo Locks season opening,” Chief Park Ranger Michelle Briggs said. “The lock opening always has a great energy. People travel from all around the region to watch this distinct Upper Peninsula way to mark the changing of the seasons.”

Everyone entering the park will be subject to a security search at the Soo Locks entry checkpoint. Firearms, weapons, drugs, pets and bicycles are prohibited.

For those unable to attend in person, the Detroit District will host a Facebook Live viewing of the event at https://www.facebook.com/USACEDetroitDistrict, starting at 11:55 p.m. Eastern time March 24.

The MacArthur Lock, south of the Poe, remains closed for maintenance until additional repairs are complete, the Corps stated in the news release.

More than 4,500 vessels, carrying up to 80 million tons of cargo, maneuver through the locks annually. Iron ore, coal, wheat and limestone are among the most frequently carried commodities. Opened in 1969, the Poe Lock is 1,200 feet long. The MacArthur Lock was opened in 1943 and is 800 feet long.

The U.S. Army Corps of Engineers, Detroit District, maintains a navigation system of 81 harbors, including the Great Lakes Connecting Channels that join lakes Superior, Michigan, Huron, St. Clair and Erie.