If a flood swamped subway or commuter-rail tunnels, it could devastate an urban area’s buried electrical cables and foul up transportation for days or weeks. That’s not just some fantasy-based, apocalyptic scenario dreamed up to scare us: It actually happened. Twenty years ago, in Chicago, a small leak in an unused freight tunnel expanded beneath the city and started a flood, which eventually gushed through the entire tunnel system. A quarter-million people were evacuated from the buildings above, nearly $2 billion in damages accrued, and it took 6 weeks to pump the tunnels dry.
Is there a way to prevent such a disaster? They don’t make corks or bottle-stoppers that big. Or do they? Building Blog reports that the U.S. Department of Homeland Security’s “Resilient Tunnel Project”
…has come up with a prototype 35,000-gallon “plug,” or “enormous inflatable cylinder,” in the words of PhysOrg.com, one that is “tunnel-shaped with rounded capsule-like ends” and “can be filled with water or air in minutes to seal off a section of tunnel before flooding gets out of control.”
The idea is to prevent underground floods from taking down whole subway systems or otherwise destroying subterranean logistical networks, such as telecom cables.
One of the companies that helped design and test the plug has many years of experience with puncture-proof materials: It designed space suits for NASA.
According to Homeland Security,
…the plug itself is made from tear-resistant fabrics—including liquid-crystal polymers—that can expand around irregular surfaces and objects, producing, in effect, an impassable blockade. The plug inflates (with water or air) to dimensions of roughly 32-feet-long and by 16-feet-wide, and holds 35,000 gallons, about the same capacity as a medium-sized backyard swimming pool. When not in use, the plug packs down to a small storage space in the tunnel, ready for remote, immediate inflation in an emergency from the tunnel system’s command center.
I realize that this is not the typical political story that one generally finds here at Occasional Planet. It is, however, a story about knowledge-based, creative problem-solving and imagination at work for the common good of our country—activities worthy of emulation by today’s cohort of Congressional politicians, whose tunnel vision [yes, pun intended] extends only as far as the next election.