THE GEOGRAPHY OF TRANSPORT SYSTEMS
The St. Lawrence Seaway is one of the world's most comprehensive inland navigation system. Initial construction work began in 1954 and involved cooperation from the Canadian and American governments. It was officially opened in 1959. On average 50 million tons of freight are transited each year by the Seaway.
Construction of the seaway did not began until 1954. It was an impressive task to be undertaken and included moving 192.5 million cubic meters of earth, adding 5.7 million cubic meters of concrete, building 72 km of dikes and digging 110 km of channels. It replaced a 14-foot (4.3 meters) deep waterway with 30 locks with a 27-foot (8.3 meters) deep channel with 15 locks. Each lock has 766 feet (233.5 meters) of usable length, 80 feet (24.4 meters) of usable width and 30 feet (9.1 meters) of depth.
One of the first construction problem to be faced was the relocation of the neighboring population of the international rapids, which was to be flooded to provide sufficient depth as well as power pools. The American side did not present much relocation problems since it was sparsely settled, but the more densely populated Canadian side presented more problems and included several riverside towns such as Iroquois, Morrisburg, Ingleside and Long Sault. Overall, the flooding of this section involved the relocation of 6,500 persons to new towns built at the expense of the project.
Different sections of the Seaway were subject to different construction works depending of the power generation potential. The International Rapids section was particularly subject to power projects such as the Saunders-Moses Dam and a set of spillway dams (Long Sault Dam) and control dams (Iroquois Dam). Provincial (or State) governments were mainly responsible to finance and undertake power projects (Hydro Ontario and New York State Power Authority) while federal governments were concerned with navigation projects.
Navigation work mainly included building locks and dredging channels to the 27 feet (8.3 meters) standard. In the International Rapids section, the United States built and dredged a 27-foot (8.3 meters) deep and 16 km long channel with two 800 feet (244 meters) long, 80 feet (24.5 meters) wide and 30 feet (9.2 meters) deep locks, the Dwight D. Eisenhower and the Bertrand H. Snell Locks. The Thousand Islands sections between Lake Ontario and the International Rapids was also dredged to 27 feet by both Canadian and American Governments. A significant share of the work was undertaken by the Canadian Government with the construction of a lock (Iroquois Lock) to bypass the Iroquois Dam, the enlargement of the Beauharnois Canal (25.7 km long) and two locks (Upper and Lower Beauharnois) and a new 32 km canal to bypass the Lachine Rapids near Montreal and which included two locks (St. Lambert and Cote Ste. Catherine). Lake St. Francois and Lake St. Louis were also dredged as well as the Welland Canal which was deepened to 27 feet.
The St. Lawrence Seaway was officially opened April 25th, 1959, and linked the Atlantic Ocean to the Great Lakes. The official opening ceremnies were held three months later on June 26th in presence of Queen Elizabeth II (representing Canada) and President Dwight D. Eisenhower. Overall, the project cost 470 million US dollars of which $336.2 million were paid by Canada and $133.8 million by the United States. Income from the operating the Seaway is thus shared accordingly.
The Seaway is generally open for navigation from early April to mid December and can accommodate ships up to 730 feet (233.5 meters) long and 76 feet (23.2 meters) wide. A typical ship designed to use the Seaway, a Laker, can carry about 25,000 tons and is 222 meters long and 23 meters wide. It takes 8 to 10 days for a ship to go from Lake Superior to the Atlantic Ocean. On the Welland Canal, the slowest section of the seaway, the average transit time is about 11 hours. For the Montreal-Lake Ontario section, the average transit time is 24 hours up bound and 22 hours down bound. The difference is mainly attributed to the current in the St. Lawrence River. Pleasure boats can also use the Seaway to go from the Great Lakes to the Atlantic Ocean, but priority is obviously given to commercial ships at locks.
| Average Transit (hours) | 90% of Transits within (hours) | 95% of Transits within (hours) | |
| Welland Canal | |||
| 11 | 9-13 | 7-15 | |
| Montreal / Lake Ontario | |||
| Inland Up | 24 | 22-26 | 20-28 |
| Inland Down | 22 | 20-24 | 18-26 |
| Ocean Up | 23 | 21-25 | 19-27 |
| Ocean Down | 22 | 20-24 | 18-26 |
Source: The St. Lawrence Seaway Authority, Annual Report 1995-1996.
At the end of the first navigation season on December 3rd 1959, 6,595 ships passed through the Seaway handling a total of 18.7 million metric tons. The tonnage passed to 20 million in 1961, 30 million in 1964, 40 million in 1966 and 50 million in 1973. In 1977 a record was reached with 57.4 million metric tons being handled by the Seaway. On average, 50 million tons of cargo are handled each year (over a period of 8 months). Over one billion tons of cargo passed over the Seaway over its first 25 years of operation (1959-84) and by 1997 this number has reached more than two billion tons handled by more than 250,000 vessels (of course most ships made more than one voyage). The seaway can accommodate roughly 41% of the world's fleet of commercial vessels of over 300 tons.
The St. Lawrence Seaway generates around 40,000 jobs and 2 billion dollars of annual personal income, but its most significant contribution is related to the cargo it handles, supporting a vast array of industries. The system carries bulk cargo such as grain, iron ore, coal and petroleum products and general cargo such as containers, steel and machinery. The first category accounts for 90% of the annual tonnage while the second account for the remaining 10%.
The St. Lawrence Seaway and the Great Lakes are thus mainly used to ship heavy raw materials and limited general cargo traffic occurs past Montreal (a major container port). One of the main reason behind such a characteristic is that general cargo is now shipped through containers and that the railway system is faster to ship containers to eastern and western seaboard ports than transporting containers through the Seaway. For instance, it takes a little more than 24 hours to transit a container by rail from Chicago to Montreal, while this operation would take around one week through the Great Lakes and the Seaway.
The St. Lawrence Seaway can be divided in four major sections, which correspond to specific infrastructures.
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Inauguration Ceremonies of the St. Lawrence Power Project, 1954
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Construction of the Ste. Catherine Lock, 1958
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First Flooding of the Lower Beauharnois Lock, 1959

First Ship to Cross the St. Lambert Lock, April 1959
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A "thousand footer" Laker ship

St. Lambert lock used for pleasure boating

Ship entering St. Lambert lock, circa 1970

Combined Traffic by Commodity, 1996
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The St. Lawrence Seaway and the Great Lakes Canal System