km 19

When the first ships navigated the Soulanges Canal in the fall of 1899, their crew discovered a modern structure built using innovative techniques that were well-suited to the needs of navigation at the time.

Lock No. 5 is a testament to this technology, with its imposing lock, its turntable bridge, and its watchtower located directly on the lock's structures, as well as the rotating railway bridge. It is the first lock that boats coming from the Great Lakes encounter as they enter the Soulanges Canal.

Due to its location, the lock was quickly considered dangerous because of the large waves brought by the southwest winds that regularly blow across Lake St-François. This issue was raised for many years until 1911, when it was decided to build an imposing breakwater and extend the south pier by 365 meters to reduce the risks.