Protecting subway and tunnel from flooding using balloon

  • “The goal is to provide flooding protection for transportation tunnels.”
  • …rather than retrofitting tunnels with metal floodgates or other expensive structures, use a relatively cheap inflatable plug to hold back floodwater.
  • So it’s not as simple as just inflating and filling the space. The plug has to be able to withstand the pressure of the water behind it.

  • The idea has been in development for more than five years…
  • …they are expected to cost about $400,000 each.
  • About $8 million has been spent on the project so far.
  • A subway tunnel is full of grease and grime – and, often, rats.
  • There are also obstructions like tracks, as well as electrified third rail, pipes and safety walkway…
  • “This is something like the air bag in your car,” he added. “You depend on it. You don’t think about it. You never use it, probably. But if you need it, it’s got to be there, and it better work.”

http://cnn.com/video/?/video/bestoftv/2012/11/01/subway-plug.cnn