SAULT STE. MARIE, Mich. (WXYZ) — The Soo Locks in Sault Ste. Marie will close Friday night for two months for critical maintenance, marking the end of the 2020 Great Lakes shipping season.
The season runs from the end of March through the middle of January.
The locks will close at 11:59 p.m. Friday through 12:01 a.m. on March 25, and every year, the winter is used to keep the locks operating.
According to the U.S. Army Corps of Engineers, there are several projects that need to be completed before reopening the locks in March.
Those projects are very unique, especially given the harsh climate in Northern Michigan during the winter.
"It is a difficult time in terms of weather to complete this work, but it keeps this important national infrastructure project operating during shipping season," Soo Area Office Area Engineer Kevin Sprague said.
The first project is to place the bulkheads. Then, the dive team goes into the freezing water to seal the bulkheads and prepare the locks for removing the water.
"Most of the maintenance projects will take place on the dewatered Poe Lock, the only lock large enough for the 1,000-foot freighters to transit," Sprague added.
Next, the team will install temporary panel bridges across the MacArthur and Poe Locks. They will help mobilize materials and equipment.
Repair on the Poe Lock upstream and downstream miter gate structure will happen. The gate allows water to be raised and lowered in the chamber.
They will also clean the Pe Lock underfloor drainage system, and drydock its barge Huron on the Poe Lock floor for repairs and painting.
More than 4,500 vessels carrying up to 80 million tons of cargo go through the locks annually. Iron ore, wheat and limestone are the most-frequent carried goods.
The Poe Lock opened in 1969 at 1,200 feet long while the MacArthur lock is 800 feet long and opened in 1943.
A second Poe-sized lock is under construction on the existing Davis and Sabin Locks sites.