St. Lawrence Seaway
Further hampered by the constrictions imposed by cold weather which often reduced the shipping season to a mere seven months in those days, the fledgling waterway offered poor competition to the growing number of locomotives steadily moving men and goods through fog and snow. If inland water transportation was to compete, it had to modernize…and it did.
Between 1850 and 1904 both the Lachine and Welland Canals were deepened to 4.3 m (14 feet). The Soulanges Canal, built to replace the Beauharnois Canal, was completed in the early 1900s. Also 4.3 m (14 feet) deep, this section was 22.5 km (14 miles) long and contained five locks, each 13.7 m (45 feet) wide and 85.3 m (280 feet) long. A new canal was also constructed at Cornwall. Miles away, at Sault Ste. Marie.
Americans and Canadians were hard at work on their respective sides of the border building the canals and locks that would link Lake Superior and Lake Huron. Finally, by 1904, all the canals and locks between Montreal and Lake Erie had the same regulating depth of 4.3 m (14 feet) although some of them – Sault Ste. Marie, for example – were somewhat deeper.
The growth of the waterway throughout the years had closely followed the evolution of the Great Lakes and St. Lawrence River fleets – from the fur traders’ canoes to small sailing vessels to schooners and, finally, steamers of larger and larger size. In 1932, Canada completed the Welland Canal, 43.5 km (27 miles) in length with a governing depth of 7.5 m (25 feet). This canal and its eight locks overcame the difference in level of 99.4 m (326 feet) between Lake Ontario and Lake Erie.
The construction of the Welland Canal marked the first step in the completion of the Seaway as we know it today.
Although a great many improvements have been made since then to increase the efficiency of both equipment and operations on the canal, the number and size of the locks have not been altered. Several factors in addition to the enormous sums involved – prevented the simultaneous completion of both the Welland Canal and the Montreal/Lake Ontario section of the Seaway.