One in a series of posts on how technology is helping in the post-Sandy recovery effort
“The work for the U.S. Army Corps of Engineers in Manhattan starts at the Brooklyn Battery Tunnel, the major underwater thoroughfare for cars passing between Brooklyn and Manhattan. Corps crews assembled at South Ferry, near the Manhattan entrance to the tunnel, have begun receiving power generators and other preliminary equipment by barge from the Navy, ahead of the high-head submersible pumps or centrifugal pumps necessary to start drainage. Task number one is to clear out the underpass to the tunnel, a task that the Corps’ Jim Pogue estimates will take about 24 hours, coming from two different sites. The expected extraction: 10 million gallons.
The crews have limited access to the submerged tunnels: there’s “only one way in and one way out,” Pogue tells Danger Room. Worse, it’s a moving target. As the water recedes, “you’re chasing it down the tunnel so the pumps have to be continuously repositioned.””
“Delp said they are the finest unwatering experts in the country, given their experience in dewatering the inundated areas of New Orleans after Hurricane Katrina. "They're subject experts," he said. "They can't do all of the work themselves but they can advise the other people in New York."
The team's tools consist of trailer-mounted trash pumps with discharge pipes 8 to 16 inches in diameter. The engine-driven self-priming pumps can pass water and even golf ball-sized debris. And if the task is too big, they can resort to less mobile pumps with discharge pipes ranging from 16 to 40 inches. The size of the pump depends on the scale of the problem. Delp said a 30-foot hole filled with water is one thing, but if that 30 foot hole is filled with water and leads to a whole subway system that stretches for miles under ground, it's a much bigger effort.”
The Army Corps of Engineers' route to draining New York City of the floodwaters from Hurricane Sandy runs through New Orleans. Workers and equipment used to help "unwater'' the metro area after Hurricanes Katrina, Rita and Isaac are headed to the Big Apple.
The unwatering team successfully removed 250 billion gallons of water from Orleans, St. Bernard and Jefferson parishes after Katrina -- enough water to fill the Mercedes Benz Superdome 267 times.
Photo Credit: Atlantic