Port activity increased in the mid-20th century with the opening of the Fourth Welland Canal in 1932, and the St. Lawrence Seaway in 1959.

In the early 1800s, the rise of steam-powered vessels and the opening of the Beauharnois Canal in 1985 and Williamsburg canal in 1849, made through travel by ship from the Atlantic Ocean to Toronto possible, greatly increasing the usage of the port.

In 1858, the Eastern Gap was dug out, making it easier to access the port from the east side of Lake Ontario.

In 1959, the St. Lawrence Seaway was opened, making the port accessible to ocean freighters with a 27-foot draft.

In 1966, Marine Terminal 51 opened at the entrance of the Shop Channel in the Port Lands.

There are 3 miles (4.8 km) of deep-water wharfage for the loading and unloading of bulk products.

Marine terminals include inside and outside storage, and some 6,000 square feet (560 m2) of berthing space for ships carrying general cargo.

[4] The tonnage of cargo passing through the port is made up mostly of sugar to the Redpath refinery and aggregate materials such as sand, gravel and salt.