With growing competition from railroads and highways, and the opening of the St. Lawrence Seaway in 1959, commercial traffic on the Erie Canal System declined dramatically in the latter part of the 20th century. Today, shipping takes place from the Atlantic Ocean to various ports on the Great Lakes using the St. Lawrence Seaway System.
The system was a joint venture of Canada and the USA to finally make a fully navigable waterway system so that a large vessel could travel from Montreal to Lake Erie.
The construction was an engineering miracle. It includes 13 Canadian locks, 2 US locks, and 5 short canals that make the system fully navigable for large freighters.
Both lake and ocean-going cargo ships enter the Gulf of St. Lawrence from the Atlantic Ocean and can go as far west as Duluth, Minnesota (the western tip of Lake Superior); or south to the tip of Lake Michigan (Chicago); or Windsor/ Detroit along the St. Clair River; or into Upper New York State through the Welland Canal into Lake Erie.
Today, the Great Lakes and the St. Lawrence River form the longest deep-draft navigation system in the world, extending 3,700 kilometers (2,300 miles) into the North American heartland. Almost 25% of Seaway traffic travels to and from overseas ports, especially from Europe, the Middle East and Africa. Every day various types of ships – cargo freighters, tankers and ferries carry loads from North America’s largest ports; including Toronto.