Old Hickory Lock, by Phil Stauder
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Most barges that pass through the Old Hickory Lock contain coal, chemicals, or sand and gravel. |
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| This is an aerial view of the Old Hickory site. There is no water flowing through the flood gates and very little passing through the powerhouse as the lake level is fairly low. Notice that the lock doors are closed and the lock is full. |
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In this aerial photo, notice that the lock is partially filled. By lowering the water level, lake pressure is kept on the doors. This facilitates a quicker lowering or raising of water as the level is "half-way" for either direction of traffic. |
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| The lock operator has many electronic devices to aid him in the locking procedure. TV cameras monitor where he cannot see, radios keep him in touch with river and lake traffic, and electronic switches tell him if the gates are closed properly. |
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Here we see a tugboat has just pushed three coal barges and a sand barge into the lock. Deck hands have just removed the cables so the tug can back out with the chemical barges still attached. |
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| Workers watch as the doors close. It takes 15-20 minutes for the water to rise in the lock. The quickest it can fill is just over twelve minutes, but the lock operator has more control if he fills the lock at a slower rate. |
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A worker prepares to move the barges through the lock as the water has almost filled it. |
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| A sisal rope, four inches in diameter is attached to a winch that will move along the side of the lock, pulling the barges forward. |
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A sisal rope, four inches in diameter is attached to a winch that will move along the side of the lock, pulling the barges forward. |
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| The deck hand must be able to stop the barges or they will drift into the lake. If he attempts to stop them abruptly, the rope will break. He must allow the rope to slip as the tension increases. |
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Meanwhile, the pilot in the tugboat waits patiently for the lock to empty so he can bring the chemical barges into the lock. |
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| The tugboat pushes chemical barges filled with benzene into the lock. |
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As doors to the lock close, a bubbler sends bubbles of air to keep debris clear of the door seal. |
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| The lock fills with water, raising the tugboat and chemical barges. |
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The tugboat slowly pushes the chemical barges toward the coal barges that are tied outside of the lock in the lake. |
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| Workers begin attaching cables to the barges to secure them to each other. |
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The tugboat pushes the six barges on their way through Old Hickory Lake. |