Early settlers arriving in the upper peninsula of what became Michigan found only one way to get from Lake Superior to the other Great Lakes,the St. Mary's River. Because of its formidable rapids, the river was a challenge to travel and transportation. Settlers needing to cross the river were forced to carry their canoes around the rapids. As settlement and trade increased, boats arriving at the river had to unload their cargo, haul them around the rapids in wagons, and reload them in other boats before continuing on their journey.
The Northwest Fur Company constructed the first canal (called the "Soo Lock") in 1797. Based on the Canadian side of the river, the thirty-eight foot lock allowed small boats to navigate the St. Mary's rapids. A lock is a section of a canal that can be closed and opened to control water level, which is raised or lowered to transport a vessel from one level to another. This first lock was destroyed during the War of 1812 (1812–1814).
For the next four decades the only way boats could pass between the Great Lakes was by a system of land rollers, which were used to circumvent the St. Mary's River rapids. In 1850 the railroad reached the region and improved transportation, but a traversable waterway was still necessary. Around the same time Michigan's Upper Peninsula was found to be rich in various ores including iron and copper. The U.S. mining industry pressed the government for a completed canal to facilitate shipment of these raw materials for use in the nation's growing manufacturing sector.
In the era when the federal and state governments were building roads and canals, and subsidizing privately owned transportation ventures (such as railroads), Congress granted 750,000 acres of Michigan public land (in lieu of monetary payment) to the Fairbanks Scale Company, which would construct the canal. The Fairbanks Company had extensive mining interests in the Upper Peninsula. Construction began in 1853 and was completed in 1855, meeting a two-year deadline set by the state. The company constructed a canal containing two locks (the State Locks), 350 feet in length, which would raise or lower sailing vessels to different water levels. The locks were turned over to the state of Michigan in May 1855.
Because of the expense of operating the locks, the state ceded management of the waterway system to the federal government in 1881. Managed by the Army Corps of Engineers, the State Locks were enlarged and an additional canal constructed (the North and South canals). In 1895, Canada built a canal on its side of the St. Mary's River which contains a single lock.
The Canadian canal, containing one lock, and the two Michigan canals, with four locks, are together known as the Sault or Soo locks (Soo is a phonetic version of Sault). They successfully allow commerce to flow between the Great Lakes and have supplied water-transported material to U.S. military forces in every major U.S. war and conflict since the 1800s. A variety of commodities pass through the locks, including grain and coal. The Soo Locks serve small passenger vessels as well as large freighters carrying over 72,000 tons of cargo. In the late 1990s, the locks averaged traffic of 10,000 vessels per year. A hydroelectric power plant supplies power to the Soo complex as well as to the power grid of Michigan's eastern Upper Peninsula.
the soo locks serve small passenger vessels as well as large freighters carrying over 72,000 tons of cargo. in the late 1990s, the locks averaged traffic of 10,000 vessels per year.