Inflatable Plugs For Tunnel Flood Protection

 This is actually a pretty creditable solution that looks to stand up. Whether the plugs are able to withstand chemical degradation for decades is quite another matter. On the other hand this is a solution out looking for a problem. For instance, can it be used as a permanent plug in a pipeline that needs to be turned on and off regularly. It could replace heavy flood gate structures.

I particularly think of the huge concrete structure built to protect London and Venice and wonder if something like this may be helpful.

On the other hand, a well placed concrete barrier in the right place may well have soared New York. Perhaps it is time we simply became paranoid and over design well past the history. Fukushimo was inexcusable and New York was also avoidable but not that obvious. The fact remains that a tsunami can rip into New York.

A plug is vastly more survivable.

Hurricane Sandy: Inflatable Plugs Might Have Minimized New York City Subway Flooding

The Huffington Post  |  By Ryan Grenoble Posted: 11/03/2012 1:02 am EDT

http://www.huffingtonpost.com/2012/11/03/hurricane-sandy-subway-plug_n_2067524.html

Employees from MTA New York City Transit work to restore the South Ferry subway station after it flooded with seawater during superstorm Sandy on Tuesday, Oct. 30, 2012. Sandy, the storm that made landfall Monday, caused multiple fatalities, halted mass transit and cut power to more than 6 million homes and businesses. (AP Photo/ Metropolitan Transportation Authority)

If an ounce of prevention is worth a pound of cure, a new technology developed by the Department of Homeland Security might have been worth its weight in gold during Hurricane Sandy.

That technology is a gigantic inflatable plug that might have prevented the massive flooding of New York City's subway system caused by the storm. In simulations, the plugs--originally developed to combat terrorist attacks and now being evaluated at West Virginia University--have proven to be effective at limiting flooding in tunnels.

Developed as part of the "Resilient Tunnel Project," the plugs are actually enormous balloon-like capsules, according to a department press release. When filled with air or 35,000 gallons of water, the plugs measure 32 feet by 16 feet. Unfilled, they take up little space and can be stashed throughout tunnels, waiting to be inflated remotely at a moment's notice.

They're tough, too. The plug's engineering uses the same design and manufacturing processes as space suits and inflatable space habitats.

"We've proved that these plugs can hold back water," Dave Cadogan of ILC Dover, the plug's manufacturer, told CNN. "I wish we had moved a little bit faster as a team and had gotten this development done."

Other brains behind the project told CNN only one current-generation plug has been manufactured, and the project is at least two years away from producing and selling them to transit agencies.