The Seaway

Great Lakes / St. Lawrence Seaway (Highway H2O) Facts

  • Opened to deep draft navigation in 1959.
  • Lock systems:
    Montreal to Lake Ontario - 2 U.S., 5 Canadian
    Welland Canal - 8 Canadian
    St. Mary's River - 4 U.S. parallel locks -- one transit (Army Corps of Engineers)
  • Vessel maximum: 225.5 m (740 ft.) length; 23.77 m (78 ft.) beam; 8.08 m (26 ft., 6 in.) draft; 35.5 m (116.5 ft.) height above water.
  • Channels maintained at 8.2 m (27 ft.) minimum depth.
  • Distance from the Atlantic Ocean to Duluth, Minnesota on Lake Superior = 2,038 nautical miles (2,342 statute miles or 3,700 kilometres), 8.5 sailing days. Includes some 245,750 square kilometres (95,000 square miles) of navigable waters.
  • Sailing time (normal conditions) between certain ports on the Great Lakes and the intersection of the Seaway ship channel and Montreal Harbor, using an average sailing time of 12 mph (10.4 knots)

Port Distance (mi.) Sailing Time (hrs.) Lockage Time (hrs.) * Total Hours
Thunder Bay 1,222 102 17 119
Duluth 1,344 112 17 129
Milwaukee 1,186 79 17 116
 
Chicago 1,251 105 17 122
Port Huron 680 57 17 74
Detroit 618 52 17 69
 
Toledo 611 51 17 68
Cleveland 534 45 17 62
Erie 439 37 17 54
 
Port Colborne 374 31 17 48
Toronto 349 29 5 34
Ogdensburg 126 11 5 16

* Welland Canal: 12 hours; Montreal / Lake Ontario: 5 hours

  • Since 1959, more than 2.5 billion tonnes of cargo estimated at $375 billion have moved to and from Canada, the United States, and nearly fifty other nations.
  • Almost 25% of Seaway traffic travels to and from overseas ports, especially in Europe, the Middle East and Africa.
  • Availability of a specialized laker fleet for maximum efficiency; many equipped with self-unloading devices for unloading at shore facilities (ship to land) or transshipping bulk cargo (ship to ship).
  • Includes some of North America's largest ports, part of an excellent intermodal transportation network.
  • Has maintained a near-perfect record of trouble-free navigation through ongoing improvements and meticulous maintenance for more than 50 years.
  • Strategic geographical location: directly serves Ontario and Quebec to the north, and Illinois, Michigan, Ohio, Indiana, Wisconsin, Minnesota, New York and Pennsylvania to the south