WASHINGTON HARBOUR, DC (WUSA) -- The roughly 40 steel gates that make up the "disappearing flood walls" were the first of their kind when built in 1986. The walls are completely unnoticeable when they are down. In fact, they have been models for similar projects all around the world.
Well-known architect Arthur Moore designed the harbour and the flood walls which took 3 years to build.
"It was painful," he says. "There was so much rain Saturday I remember wondering, 'When are they going to pull the walls up?'"
Each gate is lifted by crane individually and then a gas compressor inflates an inner tube-like mechanism inside the wall that acts as a waterproof seal. They are built to withstand floods as high as 17 feet.
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The former property manager who ran the harbour for 13 years prior to the current company says it takes nearly 5 hours to get the walls in place.
"You call Harper's Ferry and they have a gauge. If the water is up to the gauge then you know you have 32 to 36 hours to get the walls up," explained Moore. "That's how it always worked the 60 or 70 times in the past."
Written by Delia Goncalves
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