B.20 – The St. Lawrence Seaway and Regional Development

Author: Dr. Jean-Paul Rodrigue

The St. Lawrence Seaway is an inland navigation system linking the St. Lawrence River and its oceanic access to the Great Lakes through channels and locks.

1. Rationale and Construction

The St. Lawrence Seaway is one of the world’s most comprehensive inland navigation systems, the outcome of centuries of navigation and waterway developments along with the St. Lawrence and Great Lakes system where many segments are shared hydrological assets between Canada and the United States. By the 19th century, a large number of canals were being built to improve inland accessibility, particularly the Erie Canal, completed in 1825, which competed directly with the prominence of the St. Lawrence in accessing the Great Lakes. With the construction of the Lachine Canal in 1825 and the Welland Canal in 1829, in addition to specific canals and locks linking it to Lake Ontario, the St. Lawrence remained a competitive corridor to access the North American Midwest. However, by the late 19th century, rail transportation assumed prominence, rendering several canal systems uncompetitive, many of which were closed down. The only way that inland navigation could endure was with better economies of scale, which could only be achieved along the St. Lawrence but required substantial infrastructure investments.

The establishment of the International Joint Commission in 1909 to help resolve water development issues between Canada and the United States provided renewed impetus. After conducting a series of studies about the system, its constraints, and its commercial potential, the commission recommended the construction of the St. Lawrence Seaway. However, two groups lobbied against the project since it was perceived to have a negative impact on their businesses:

  • Railway companies saw the seaway as a direct competitor for their inland freight distribution system in the Midwest. By the early 20th century, rail development had reached a phase of maturity in North America and was beginning a phase of rationalization.
  • East coast ports, with the exception of those along St. Lawrence (mainly Montreal), that also saw the seaway as a competitor.

Additionally, World War I and the Great Depression of the 1930s created a negative commercial environment. By the late 1940s, pressures were mounting to improve the waterways, particularly since it also involved the opportunity to build new hydroelectric power plants. Still, the project was rejected by the US Senate until 1954, when the Canadian government declared that it would unilaterally build the Seaway on its side of the border. Initial construction work thus began in 1954 with the full cooperation of the Canadian and American governments. Moving 192.5 million cubic meters of earth, pouring 5.7 million cubic meters of concrete, building 72 km of dikes, and digging 110 km of channels were impressive tasks. The goal was to replace 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 challenges 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. In total, 260 square kilometers of land were expropriated. The American side did not present many relocation problems since it was sparsely settled, but the more densely populated Canadian side included several riverside towns such as Iroquois, Morrisburg, Ingleside, and Long Sault. Overall, the flooding of this section involved the relocation of 6,500 residents to new towns built at the expense of the project.

Different sections of the Seaway were subject to different construction works depending on the power generation potential. The International Rapids section was particularly subject to hydroelectric 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 for financing and undertaking 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 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 were also dredged to 27 feet by 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 opened to commercial navigation on April 25th, 1959. The official opening ceremonies were held three months later, on June 26th, in the 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 was paid by Canada and $133.8 million by the United States. Income from the operations of the Seaway is thus shared accordingly between the two federal agencies responsible for its management and upkeep; the Saint Lawrence Seaway Management Corporation (Canada) and the Saint Lawrence Seaway Development Corporation (United States).

2. Sections of the Seaway

The St. Lawrence Seaway is only one part of a greater navigation system and should not be confused with the St. Lawrence River or the Great Lakes. It is overall a relatively small section of the system that begins in Montreal, goes through Lake Ontario, and ends at Lake Erie at the outcome of the Welland Canal. Navigation beyond that point is no longer considered part of the seaway. The St. Lawrence Seaway can be divided into four major sections corresponding to specific infrastructures.

  • Lachine Section. This 50 km section is the doorway of the St. Lawrence Seaway, which begins around 1 km east of the Jacques Cartier Bridge. Its main purpose is to bypass the Lachine Rapids, the first major natural obstacle along the St. Lawrence. Instead of using the north shore, as the Lachine Canal did, the Seaway passes through the south shore, a much longer route. The main rationale was to avoid passing through the congested Montreal harbor and the St. Mary’s Current. Also, the south shore presented fewer impacts over the waterfront as well as better integration with existing transport infrastructure. Two locks provide a 45-foot (13-meter) climb, the St. Lambert Lock and the Cote Ste. Catherine Lock.
  • Beauharnois Section. This 74 km section extends from the end of Lake St. Louis to Cornwall in Ontario. It serves two major purposes, which are navigation and power generation. Two 42 feet (12 meters) lift dams were built, the Upper and Lower Beauharnois locks, permitting the Seaway to cross the Cascades, Split Rock, Cedars, and Coteau Rapids between Lake St. Louis and Lake St. Francois. The second purpose is a power dam taking advantage of an 80-foot (24-meter) drop, the Beauharnois Power Plant. This power plant is supported by a set of dams that regulate the flow along this section.
  • International Section. Such as the Beauharnois section, the International section has been the object of navigation and power works, but this section is jointly administered by Canada and the United States. It is 71 km long and consists of a set of dams (Long Sault and Iroquois), powerhouses, locks (IroquoisDwight. D. Eisenhower, and Bertrand H. Snell), channels, and dikes, creating vast power pools. This section climbs 93 feet (28 meters). It can be subdivided between the International Rapids and Thousand Islands sections.
  • Great Lakes Channels. This section is composed of a series of channels and locks linking the Great Lakes together. The Welland Canal is the most significant, with eight locks climbing 326 feet (99 meters) from Lake Ontario to Lake Erie, where the seaway ends. The channels linking Lake Erie and Lake Huron (St. Claire River, Lake St. Claire and Detroit River), Lake Huron and Lake Michigan (Straits of Mackinac), and Lake Huron and Lake Superior (St. Mary’s River and Soo Locks, a 6 meters climb) are also part of this system, but not considered to be part of the seaway.

Further, the St. Lawrence is part of the North American system of river and coastal navigation, which is complementing the existing railway and highway systems.

3. Navigation and Cargo Carried

The Seaway is generally open for navigation from late March / early April to mid-December, which is about 275 days. It can accommodate ships up to 766 feet (233.5 meters) long and 80 feet (24.4 meters) wide in the range of 30,000 dwt. The draft of the Seaway was upgraded in 2006 to 26’6″, and there are plans to expand the draft to 26’9″. Each additional inch of draft enables a ship to carry an additional 500 tons. 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. This ship class is also referred to as Seawaymax since it was designed to fit specifically in the Seaway’s locks. 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 upstream and 22 hours downstream. The difference is mainly attributed to the downstream river current. 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.

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 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, and since then, this record has remained unsurpassed. On average, 50 million tons of cargo are handled each year (over a period of 8 months), and the majority of the flows are downbound (from the Great Lakes to the Atlantic). Over one billion tons of cargo passed over the Seaway over its first 25 years of operation (1959-84), and by 1997, this number had reached more than two billion tons handled by more than 250,000 vessel trips. Still, the Seaway remains used at about 50% of its design capacity.

It is estimated that 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 a composition of 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 accounts for the remaining 10%.

  • Grain. It is the most important cargo in terms of volume and accounts for 40% of all the cargo handled. Most of the grain comes from the American and Canadian prairies (mostly Manitoba and Saskatchewan) and is exported to international markets through the Seaway. Wheat accounts for 50% of the total grain, while corn and soybeans take 30%. Barley, oats, rye, and other grains account for the 20% that remains. Several ports along the Seaway have grain-handling infrastructures.
  • Iron Ore. Iron ore is the second most important commodity, accounting for a third of all the cargo handled. It is generally shipped from mines in Labrador, Quebec, Ontario, and Minnesota (Mesabi Range) to ports along the St. Lawrence or the Great Lakes and then to steel mills. Pittsburgh was (and is still) one of the most significant steel production centers of the Great Lakes.
  • Coal. Coal is used for steel making or to heat thermal plants for electricity production. The Appalachians are a major coal extraction region of the United States, and coal is then shipped from the mines to the ports of Lake Erie and then to other plants of the region or the international market.
  • Steel. With 10% of the total annual tonnage, steel is mainly used by heavy industries such as construction and the automotive industry.

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 reasons behind such a characteristic is that general cargo is now shipped through containers. The railway system is faster to ship containers to eastern and western seaboard ports than to transport 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. Additionally, the fact that the Seaway is closed for about three months is incompatible with supply chain management, which requires constant flows. Since the peak season for containerized cargo is mostly between April and November, using the Seaway may represent a niche market for import retail cargo where empty containers could be filled with commodities on the return trip.

They were oceanic containership services using the Seaway in the 1960s and 1970s with ships of about 800 TEUs, mostly with the UK. They were abandoned afterward as containerships got bigger and as specialized container terminals started to emerge. In 2009, a container barge service with a weekly rotation between Hamilton and Montreal was inaugurated but canceled the year after because of the lack of demand. In 2014, a new oceangoing service between the Port of Cleveland and Antwerp was inaugurated. It combines breakbulk and container cargoes on specifically designed self-unloading ships. The extent to which the Seaway can be used for container transportation and its role in North American freight transportation remains to be seen.

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