There were some some definite concerns that either due to a major storm
or a terrorist attack that subway tunnels are vulnerable to flooding.
An issue with subway tunnels is that if you have a breach where a single tunnel starts to flood
there's a lot of interconnectivity.
So one tunnel is connected with other tunnels and stations.
And so a seemingly isolated incident in one part of a subway system could actually flood a large part of the network.
You know when this project was first initially thought about at DHS S&T,
DHS S&T was a pretty young organization at that time and was reaching out
to different organizations that they had access to, to help them with various projects.
This was a completely kind of wild and crazy out of the box idea.
We sat down and talked about possible solutions to the problem
and came up with the idea that maybe an inflatable balloon or a plug could somehow be deployed in a tunnel
and quickly deploy to contain flooding in a subway tunnel to a very small area
and a lot of people thought that it was not a good idea that it would not work there was no way to make it work.
Water pressing in on a tunnel full of rushing water, water is very heavy.
And this tunnel plug is made of fabric.
So we had to do some initial work just to figure out if the concepts were even possible.
Systems engineering was a large part of what we brought to the table there.
We laid out a plan that included doing a proof of concept, a simple proof of concept
to as the first step to just kind of prove that we could install a lightweight plug
in a reasonable period of time in a tunnel,
deploy it and get a reasonable reaction in terms of sealing that tunnel off
and we were successful.
Well one of the complexities is just the subway itself.
I mean a subway is a dirty environment.
It's physically dirty, the tunnels are irregularly shaped.
There are rails to be dealt with.
There are conduits and pipes and wires.
So there is a lot of operational hazards in a tunnel
that make it very difficult to design something like this plug.
So specifically one thing we had to worry about was shape,
some of the others were just related to the engineering of the plug itself
coming up with the materials that were strong enough
to be implated to the necessary pressures to hold back the water.
ILC also got involved in 2008.
We were approached by DHS S&T and West Virginia University
to bring our soft goods expertise to bear in solving the problem
of creating a high strength inflatable structure.
We looked for manufacturers, scientific organizations with the expertise
to build a stronger more durable plug that would be successful in holding back floodwaters.
And we identified ILC Dover here in Delaware
that had done a lot of work for NASA designing spacesuits
working with the Department of Defense
and other agencies with high strength designed inflatable products.
So recently we completed a series of tests to evaluate
the performance of the plug and not just the plug
but the plug, the storage container, the inflation pumps necessary to inflate the pump to full pressure
and the control systems to make sure that the plug pressure is modulated properly.
We successfully performed three separate tests
which were a requirement for our primary transit agency customer
and beyond that we did a fourth test which we called a long duration
or 21 day test. This was also a critical requirement and that entailed
inflating the plug and instead of bringing water in behind the plug
and leaving it at pressure for one hour.
We did a 21 day test with a plug in place
fully inflated operational pressure with water pressurized behind the plug
and the plug did nothing for 21 days.
What we've done with the ability to pack these structures into such a small space
is to mount them, store them right at the point of use.
It brings so much resiliency to the system and reduces risk because
nothing is going to get lost.
They can keep the system open till the very last minute so there's safety
in being able to use the system.
And then the economic impact to the system is reduced because the transit system is open longer.