The canal’s history

The Soulanges canal has an important place in the development of navigation as well as in the expansion of maritime commerce in Canada.

Our regional museum presents to you its history!

A rushing river

The Soulanges canal has an important place in the development of navigation as well as in the expansion of maritime commerce in Canada. Its history is part of this great human and technological adventure that allowed, during the last 2 centuries, to go around the tumultuous waters of the Saint Lawrence river to reach the interior of the continent. Indeed, at this area, the river has a series of rapids, formed by four slope breaks totaling a drop of 25,6 meters over 12,8 kilometers.

Le Trou rapids in Pointe-des-Cascades (before 1893)
Source : © Centre d’archives de Vaudreuil-Soulanges, Fonds Pierre Clément, P-20-220

1840 to 1899

At the end of the 19th century, the decision of building a new canal is becoming inevitable. Indeed, the need to replace the Beauharnois canal with a larger one is becoming more pressing, because the expansion of maritime commerce now requires bigger ships. The construction of the Soulanges canal lasted for 7 years, between the start in June of 1892 and the passing of the first boat on October 9th, 1899. It’s quite a tale, one which forever transformed the landscape of the region and the way of life of its population.

A quite uneven course (around 1940)
Source : © Centre d’archives de Vaudreuil-Soulanges, Fonds Pierre Clément, P-20-101

Impacts on the population

The 23.4 kilometer journey, suggested by the engineer in charge of the works, Thomas Monro, won’t be without consequences for the population of the four municipalities located on its path. The towns of Pointe-des-Cascades and Les Coteaux, located at the extremities of the canal, will go through significant physical transformations, such as many buildings being demolished. Many land owners will see portions of their land being expropriated and lots of farmers will now have to take long detours to the nearest bridge to access the most important part of their fields.

Aerial view of the Soulanges canal at Pointe-des-Cascades (first half of the 20th century)
Source : © Centre d’archives de Vaudreuil-Soulanges, Fonds Pierre Clément, P-20-124

A technological epic

Construction of the Soulanges canal turned out to be a longer and more arduous task than what the preliminary studies had shown. Many factors contributed to the complexification of the works, significantly delaying its opening. One of them was the nature of the soil itself in Soulanges, against which the workers and contractors fought tirelessly for seven years. To meet deadlines and to face the many intangible factors plaguing the construction, over 1 200 workers could be on site at the same time, distributed along this huge construction site.

Workers installing riprap on the shores of the Soulanges canal (around 1897)
Source : © Centre d’archives de Vaudreuil-Soulanges, Fonds Pierre Clément, P-20-215

The works continue

While anticipated, the presence of a high number of rocks on the pathway as well as the instability of this clayey soil resting on a sand bed, caused considerable problems. Preliminary reports had underestimated the consequences of this geological phenomenon and frequent screes would complicate the works. In the sections going through the municipalities of Les Coteaux and Coteau-du-Lac, presence of soft and oily blue clay would cause frequent landslides. Engineers in charge of the works will order the shores to be flattened and riprap to be installed on them at certain strategic points. Concrete dykes, used to solidify the walls of the structure, are placed along the course.

Mechanical shovels attacking the clayey soil (Coteau-du-LacSeptember 24th, 1895)
Source : © Bibliothèque et Archives Canada, C-20869

An illuminated canal

The most remarkable technological innovation that was used at the Soulanges canal is without a doubt hydroelectricity. The electrification of the canal has allowed the actuation of the motors of all the moving structures such as locks, swing bridges and spillways, thus reducing the number of employees required for the proper operation of the canal. Electric street lamps, distributed along the path, now allowed for ships to go through the canal day and night.

The Soulanges canal, illuminated (after 1902)
Photo taken from the railway bridge at the number 5 lock in Coteau-du-Lac
Source : © The Canadian Engineer

The « Petit pouvoir » in Les Cèdres

This hydroelectric energy was provided by a small power plant, built in 1899 by engineer Thomas Monro, located at the meeting point of the Soulanges canal and the rivière à la Graisse in Les Cèdres. This location. chosen because of its six-meter drop between the canal and the river, ensured sufficient hydraulic force to turn the turbines of the power plant. Although designed for an industrial purpose, the architecture of this building stands out by its “castle” style that was in vogue in the 1870s and that we can find in a series of hotels, such as the Château Frontenac in Quebec City.

« Le Petit pouvoir », the Soulanges canal’s hydroelectric power plant (October 4th, 1910)
Source : © Bibliothèque et Archives Canada, C-63798

The end of an era

The ever-increasing dimensions of the ships going through the canal as well as their numbers will mark the end of this installation. The size of the locks not being able to indefinitely meet these various imperatives, the last ships went through the canal one last time in fall of 1958. The official inauguration of the Saint Lawrence Seaway, in use today, on June 26th, 1959 definitely sealed the fate of the Soulanges canal, considered for a long time one of the biggest feats of engineering of the 19th century in Canada.

The end of an era (July 30th, 1955)
Photo courtesy of Mr. Bernard Prieur
Source : © Centre d’archives de Vaudreuil-Soulanges, Fonds Canal de Soulanges, 103


Texts and research : Musée régional de Vaudreuil-Soulanges.

Other consultation: Sébastien Daviau and Édith Prégent. Le canal de Soulanges (1899-1958) : une aventure technologique et humaine. Vaudreuil-Dorion, Musée régional de Vaudreuil-Soulanges / Musée virtuel du Canada – Histoire de chez nous, 2010.

François Cartier. Canal de Soulanges. D’un défi à l’autre. Les Coteaux, Société de développement du canal de Soulanges / Musée régional de Vaudreuil-Soulanges, 1999.