How It Works: Locking Through

How It Works: Locking Through. . , For more on the history of the Welland Canals, please visit our galleries inside the Museum. , A lock is a bit like a watertight bathtub with gates on both ends. To fill the lock chamber, water is let in from the upper channel through an intake valve, into the sluice tunnel and into the lock chamber via "windows" along the bottom of the chamber. The water level in the chamber needs to match the water level of the channel from which the ship is entering., Photo Length of Locks: 261m / 859ft , Width of Locks:24m / 80ft , Depth of Locks: 25.3m / 83ft , Draught: 9m / 30 ft , .Lock gate, closed before ship enters, to allow water to rise and equal depth of water ship is in. , .Discharge valve controls water drainage from lock, in closed position to hold water in until lock needs to drain water to lower ship , . Lock gate, open to allow ship to enter. Lock Gate Height 10.7m / 35ft , .Water intake, located below water line. , . 1.2 x .9m (4 ft x 3ft) windows along the bottom of the lock allow water to pass into or out o the lock chamber., Once the ship is held or tied safely in place the gates will close and the water will begin to drain through the sluice tunnels, lowering the ship. There are no pumps on the Canal. Water is always flowing north, and the locks are filled or emptied using gravity and water is let into the lock from above and let out the bottom to empty the lock. This system is known as a slack water Canal system, which uses locks, weirs, dams, and ponds to control and maintain water levels. , Photo: 92 million litres , 20 million gallons of water , . Discharge valve in open position as water is drained from lock chamber to lower ship. , . The intake valve controls water flow to sluice tunnel. Closed in this position. , . The sluice tunnel moves water into and out of the lock chamber, depending on the position of intake/discharge valves., If not used to lock through, extra water not held in the large reservoir ponds will pass over the waste weir. Turbines at Lock 1,2,3 waste weirs generate a small amount of electricity which powers operations at the St. Lawrence Seaway Corporation and here at the St. Catharines Museum and Welland Canals Centre., Once the water has drained and matches the level of the down-bound channel, the 500-ton lock gates open to allow the ship to continue. The gates are operated using a hydraulic arm and sit on large tracks at the bottom of the lock chamber. Ships traveling up-bound follow essentially the same process except in reverse. Remember even when travelling up-bound, the lock is being filled from the channel above., Photo: Time to fill and empty lock: 12min. , Time to lock through: 30 min , . Lock gate, open to allow ship to exit lock. , . Lock gate height 25m / 82ft. , . intake valve remains closed until the lock needs to be filled to raise the level of the water.