The Soo Locks

The St. Mary’s Rapids is about one quarter of a mile wide and three quarters of a mile long. The fall of water ranges from 18 to 24 feet with the varying stages of water. The first canal was built on the Canadian side of the river by the Northwest Fur Co. in 1797-98. The lock was 38 feet long, 8 feet 9 inches wide, with a lift of 9 feet. The lock, excepting its timber floor and miter sills, was destroyed in 1814 by United States troops from Mackinac Island under the command of Major Holmes. The first ship canal known as the state canal, was built on the American side of the river in 1853 to 1855; some 750,000 acres of land in Michigan having been granted by the United States Congress for the construction thereof. The canal was 1 1/12 miles long, 64 feet wide at the bottom, and 100 feet at the water surface. There were two tandem locks of masonry, each 350 feet long by 70 feet wide, with a lift of about 9 feet. The depth in the canal was about 13 feet and in the locks about 11 ½ feet at the stage of water then prevailing. The locks were destroyed in 1888 by excavators for the present Poe Lock.

The Locks And Canals

The MacArthur Lock, 800 feet long between inner gates, 80 feet wide, and having 31.0 feet of water on the miter sills at present low-water datum, was built by the United States in the years 1942 to 1943 and opened to traffic July 11, 1943

The Poe Lock, 704 feet long between inner gates, 100 feet wide, and originally having 22 feet of water on the sills (16.6 feet at low-water datum), was built by the United States in the years 1887 to 1896.

The proposed new lock to replace the old Poe Lock will be 1200 feet long and 110 feet wide.

The Davis Lock, 1350 feet long between inner gates, 80 feet wide, and originally having 24 feet of water on the miter sills (23.1 feet at present low-water datum), was built by the United States in the years 1908 to 1914, and opened to traffic October 21 of the latter year.

The Sabin Lock, of the same dimensions as the Davis Lock, was built by the United States in the years 1913 to 1919 and opened to traffic September 18, 1919.

The present low-water planes are 601.1 feet, at the head, and 579.4 feet at the foot of the locks, above mean tide at New York, levels of 1935.

All traffic, through both the United States locks and the Canadian lock, is passed free of tolls in Sault Ste. Marie, Michigan and Ontario.

As many as 600 different vessels pass through these locks in a year, varying in size from small non-freight carrying vessels to large vessels carrying more than 26,000 tons of freight in a single cargo.