The St. Lawrence / Great Lakes System
The St. Lawrence is part of a complex system, which includes the Great Lakes, the St. Lawrence Seaway and a dredged channel between Quebec and Montreal. The main purpose of the Seaway is to provide a maritime link between Montreal, an ocean port, and the Great Lakes by using a series of locks and canals. The best known is the Welland Canal linking Lake Ontario and Lake Erie, a 99 meters climb over the Niagara escarpment. A major issue for the seaway is related to its limited capacity and being closed for about 3 months during the winter.
The St. Lawrence itself can be subdivided between the estuary which is accessible to deep navigation and the river where vessels close to the Panamax standard can access year round the Port of Montreal. The channel between Quebec and Montreal has a depth of 11.3 meters (37 feet) and can handle containerships up to 4,200 TEU.
Length 3,060 km
St. Lawrence sub-basin 574,000 sq. km
Great Lakes sub-basin 770,200 sq. km
Total basin 1,344,200 sq. km
Mean flow 10 cubic m./s
Population About 5 millions over a 10 km-wide strip along the St. Lawrence. If the St. Lawrence / Great Lakes region is considered, a total of 90 million people.
Economic facts 40% of American manufacturing (70% of steel production) and 66% of Canada's industrial production in the region.