Following the boom of shipbuilding on the
Great Lakes during the
Second World War, the
Muir Dry Dock was closed down at
Port Dalhousie, Ontario and operations were moved to the east side of the
Welland Canal at
Port Weller, Ontario in 1946. 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. The new site was considered an improvement over the Muir Dry Dock due to its location above Lock 1, which eliminated the need for pumps to fill or empty the dry dock. The yard was expanded to include ship repair and reconstruction work and employed 500 by 1950. In 1956, the yard was sold to the
Upper Lakes Shipping Company. 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. By the 1990s, the Port Weller Dry Docks was the lone
Great Lakes shipyard in operation in Canada. It was sold to Canadian Shipbuilding & Engineering Ltd. but later became
insolvent. The shipyard was reacquired by Upper Lakes Group in 2007, along with a dockyard in
Thunder Bay, Ontario. The company reorganized the shipyards, and other endeavours in
Hamilton and
Port Colborne, Ontario into a new division named
Seaway Marine & Industrial Incorporated. 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. The yard was used briefly in 2015 by
Algoma Central to perform maintenance work on self-unloading bulk carrier and was leased by Saint Lawrence Seaway (current owner of the facility). The site is operated by
Heddle Marine (now Ontario Shipyards) on behalf of St. Lawrence Seaway. In 2017, arrived to overwinter at the site. ==Ships==