Why are locks needed on the st. Lawrence seaways?

- The locks serve as passageways to facilitate the movement of vessels between water bodies with different elevations, allowing ships to navigate safely through the changing water levels.

- To compensate for the variations in water levels between Lake Ontario and the Montreal area, the St. Lawrence Seaway incorporates seven locks in total:

- St. Lambert Lock and Upper Beauharnois Lock on the Canadian side just upstream of Montreal

- Eisenhower Lock, Bertrand H. Snell Lock, Dwight D. Eisenhower II Lock, Robert H Saunders Lock, and Iroquois Lock on the U.S. side, which are located near Massena, New York.

- These locks operate in pairs to elevate or lower vessels by 22.9 meters (75 feet), which is the total difference in water level between Lake Ontario and Montreal.

- When ships travel from Lake Ontario towards the Montreal area, the locks raise them gradually to the higher water levels. Conversely, when vessels move in the opposite direction, the locks lower them safely to the lower water levels.

- The process of navigating through the locks is highly controlled to ensure the safe and efficient passage of vessels. Each lock has a large chamber that can accommodate ships varying in size and weight, and the water level within the chamber is adjusted to match the desired elevation. As the water levels change, the massive lock gates open and close to allow the vessels in or out.

- The St. Lawrence Seaway locks play a crucial role in facilitating commercial transportation and trade between the Great Lakes region of North America and the Atlantic Ocean. They enable large ships to navigate the difference in water levels and access major ports and industrial centers in the heartland of the continent, contributing significantly to the economic growth and prosperity of the region.