Welland Canal
The Welland Canal locks allow large ships over 200 yards in length that may weigh approximately 30,000 tons to travel between Lake Ontario and Lake Erie in spite of the 326.5 ft. difference in elevation. The Welland Canal locks lift and lower these ships with the help of gravity and large quantities of water. The force of gravity is used to fill or drain a lock moving about 20 million gallons of water in about 11 minutes. It is this movement of water that actually lifts or lowers a ship in a lock. The force of gravity is so strong that it draws this water a distance of 27 miles from lake Erie to Lake Ontario filling and draining the 8 locks in between. (wellandcanal.com)
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