Why did many manufacturing industries leave Montreal for suburban areas in the mid-20th century?

During the mid-20th century, many manufacturing industries relocated from Montreal to suburban areas primarily due to a significant shift in the transportation of goods from rail to road.1

Historically, Montreal’s industrial growth was tied to its status as a major transportation hub, with factories lining the Lachine Canal to take advantage of water and rail access. However, as road transportation became the preferred method for moving goods, the logistical advantages of being situated in the city center diminished, prompting a flight of industries toward the suburbs. This transition occurred alongside broader post-World War II economic changes, which eventually saw the decline of traditional, labour-intensive manufacturing sectors in favor of high-tech industries and a service-oriented economy.12