Dover engineering firm develops ‘tunnel plug’ to minimize floods [video]

A “tunnel plug” designed to minimize flooding in subway systems is a Dover engineering firm’s newest brainchild.

ILC Dover, which specializes in aerospace soft goods such as materials for astronaut suits, unveiled the fruits of its “Resilient Tunnel Plug Project” on Tuesday at its headquarters in Frederica.

In partnership with the U.S. Department of Homeland Security and West Virginia University, ILC Dover has developed three types of flood protection devices during the ambitious decade-long project.

“There were a lot of tough technical challenges in making this happen,” said John Fortune, a homeland security engineer.

Tunnel flooding has caused billions of dollars of damage and endangered hundreds of lives, and the tunnel plug aims to reduce those risks. Currently, it’s primarily designed to block water, but project officials said they hope to make improvements to the technology so it can alleviate damage from terror attacks and fires.

Made of three layers of woven high-strength textiles, the plug is able to withstand flood water pressure when inflated with compressed air to stop the spread of floods.

“This Resilient Tunnel Plug has a skin stress of about 2,000 pounds per square inch, it’s just an amazingly strong inflatable structure,” said Dave Cadogan, ILC’s product development director.

The tunnel plug is contained in a specially designed container that is attached to the walls of tunnels — such as those in underground subway systems — that will inflate to its full size in 12 minutes upon being engaged.

Greg Holter, a federal contractor on the project, said the plug is designed to be installed on a tunnel’s walls.

“One of the things that we discovered when we were working with this is that you can’t just roll a plug up and put it in there,” Holter said. “The fabric is pretty heavy so if you just put it in there and drop it on the floor and try to inflate it, it won’t really reach the ceiling.”

ILC test the plug for reporters and camera crews, Engineers tested the plug by inflating the device in a testing tunnel constructed at WVU. They filled the tunnel with water and voila — only a few trickles were visible on the edges.

The plug has undergone rigorous testing, withstanding high water pressures for a full 21 days, project officials said. The technology already has one buyer, but officials would not identify the client or discuss prices.

ILC Dover is a “gem of Delaware” said Cadogan, a 31-year employee. “It’s not only aerospace that we at ILC Dover work on, it’s really our expertise in inflatable structures that brought the Department of Homeland Security to us … and there aren’t too many people in the world who can do that.”