First installation of inflatable balloons to protect tunnels from flooding

The Resilient Tunnel Plug (RTP) seems to be the solution against tunnel flooding, eliminating all the disastrous consequences that have been observed in the past.

The plug is being developed by the firm ILC Dover in Delaware and its first installation was completed after two demonstrations at New York's South Ferry station this year. This woven balloon will remain packed on the side of the tunnel portal and when a storm approaches it will be deployed remotely. It is designed to be filled with up to 35,000 gallons of air or water, sealing the surrounded walls. It is also considered able to withstand up to 17 pounds per square inch of force.

You can find more information about the inflatable plugs and the research project here: Next Generation Geosynthetic? Inflatable balloons that seal off tunnel portals and protect them from flooding

Sources: FastCoExist , TimeOut New York