Great Lakes Shipping

• The St. Lawrence Seaway opened in April of 1959.
• The Seaway extends 2,340 miles from the Atlantic Ocean to the head of the Great Lakes.
• The Seaway includes a system of locks that lift ships up and down over three areas where barriers to shipping are encountered.
• The Seaway system is connected by 6 short canals with a total length of less than 60 nautical miles.
• There are 19 locks, filled and emptied by gravity.
• Ships measuring up to 740 feet in length and 78 feet in the beam are routinely raised to more than 590 feet above sea level, as high as a 60-story building.
• The ships are twice as long and half as wide as a football field and carry cargoes the equivalent of 27,500 tons.
• Each lock is 766 feet long, 80 feet wide and 30 feet deep over the sill.
• A lock fills with approximately 24 million gallons of water in just 7 to 10 minutes.
• Getting through a lock takes about 45 minutes.
• Annual commerce exceeds 200 million net tons.
• It is estimated that between 6,000 and 10,000 ships have sunk or been stranded on the Great Lakes since the early 1800s.