Project’s Principal Engineer or Firm: U.S. Army Corps of Engineers

Originally Constructed: 1855

Original Construction Cost: Davis Lock A: $2,200,000;

Sabin Lock A: $1,750,000

Date of Major Updates: 1914, 1919, 1943, 1968

Principal Original Contractor: Fairbanks Scale Company (1855); Great Lakes Dredge & Dock (1943);

McNamara Construction of Manitoba (1968)
Description:
The Soo Locks present a safe passage for deep-draft ships around the 21-foot drop over the St. Mary’s River Falls between the United States and Canada at Sault Ste. Marie. The four modern locks allow commercial shipping vessels to navigate around this treacherous river passage to connect Lake Superior with the other Great Lakes. The Davis Lock, the oldest existing lock, was constructed in 1914. It is 1350 feet long, 80 feet wide and 23 feet deep. The Poe Lock, the largest lock, was constructed in 1968 and is capable of handling super freighters. It is 1200 feet long, 110 feet wide and 32 feet deep. The locks can accommodate ships carrying 72,000 tons of cargo. The water level in a lock can be fully raised or lowered in between 6 to 15 minutes. During wars, the locks served the national defense effort by allowing raw materials from the Great Lakes region to be supplied to mills on the lower lakes. More recently commodities passing through the locks include taconite pellets, grain and low sulfur coal. With 10,000 vessels per year passing through the Soo Locks, it ranks among the world’s busiest waterways.