This summer the Soo Locks at Sault Ste. Marie in the Upper Peninsula will celebrate the 150th anniversary with a series of celebrations and events. The Soo Locks connect Lake Superior with Lake Huron by bypassing the rapids of the St. Marys River.
Lake Superior is about 21 feet higher than Lake Huron, and until the first locks were built in 1797, traders and trappers had to portage their canoes around the St. Marys rapids. Those first locks, a mere 38 feet long, were built on the Canadian side by the Northwest Fur Company and allowed canoes and small boats to pass between the lakes.
Those locks were destroyed in the War of 1812 and the next set of two, this time built on the American side, were 350 feet long and completed in 1835. Those were done by the State of Michigan but were turned over to the U.S. Army Corps of Engineers in 1881.
MORE THAN PANAMA
Nowadays, as then, the size of the locks limits the capacity of ships moving into and out of Lake Superior. Not many people are aware that the Soo locks carry more tonnage than the Panama Canal. The reason is in the nature of the cargoes. The bulk carriers on Lake Superior carry iron ore, coal, and salt: all heavy products.