In October 2012, Hurricane Sandy swept up the East Coast and left more than $70 billion in damage in its aftermath. Among the damage was the 155th Street subway station in New York City. The station sits about a block from the Harlem River, and during the storm, water rushed down the stairway and flooded the station. The New York Metropolitan Transit Administration (MTA) chose this as one of seven stations for a flood mitigation plan.
A flood mitigation system with a stainless steel balustrade evokes the ocean and protects a subway
Photos courtesy of Urbahn Architects
The entrance to the station is a 28-foot-wide staircase, and Urbahn Architects, New York City, designed a retention wall system that features flood logs across the stairway and a glass balustrade protected by stainless steel around the entrance. The system is capable of withstanding loads of up to 65 inches of water.
Such a system needs to be durable. Plus, “it was in a residential neighborhood and in a park setting,” says Nandini Sengupta, LEED AP, senior associate architect, Urbahn. “But first and foremost, it was MTA’s main consideration that the material has to be durable and maintenance free. All of those things came first, and with that we tried to bring in our aesthetic considerations as well.”
The result is a portable, stackable system that runs across the stairway and can be stored in a room within the station. The balustrade is 9/16-inch-thick tempered, laminated glass because safety concerns required sight lines. But the glass needed to be protected from vandalism, so Urbahn sandwiched it in a stainless steel rib veneer.
“We wanted to create a safeguard around the glass so people couldn’t tamper with it and compromise any of the components of the flood barrier,” says Jonathan Ruiz, associate architect, Urbahn.
The fins are embedded in granite and are shadow images of each other. As one curves inward on the exterior side, the fin on the inside bends outward. They are 1/4-inch-thick and spaced at 4 inches on-center.
The wave pattern evokes the near-by waters and the purpose of the barrier system. “It speaks to the idea that we’re not really dealing with the impacts of climate change,” says Ruiz.
Originally the wave pattern was far more radical. “We tried to make it more cost effective,” says Ruiz. “We got rid of a lot of the more radical curves and gestures. We straightened it out.” By making one side of the fin positive and other negative, the fabricators, Mid-State Construction Corp., North Arlington, N.J., was able to cut an interior fin and exterior fin from one piece of stainless steel.