The drydock, opened in 1947, was initially owned by the Government of Canada and was used to store gates, lock valves, and gate-lifting vessels.
Under their management, the shipyard began to construct vessels of different types, such as bulk carriers, tankers, tugboats, scows, barges, car ferries and icebreakers.
The Port Weller Dry Docks expanded its activities with the opening of the Saint Lawrence Seaway in the late 1950s.
The company reorganized the shipyards, and other endeavours in Hamilton and Port Colborne, Ontario into a new division named Seaway Marine & Industrial Incorporated.
[3] They renamed the facility Seaway Marine and Industrial Limited, but the firm went bankrupt in 2013, resulting in the closure of the shipyard and loss of jobs.