Protecting Wellington from a tsunami

Currently there are many places around the world that utilise tsunami walls but in reality as seen in the recent Japan quake, these tsunami walls just weren't enough. Even the 9 metre walls that dominated the landscape of Ryoishi were to short.



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To have walls tall enough to stop a 10metre tsunami surrounding Wellington would be extremely intrusive and unattractive. My concept is to install 30metre inflatable walls around along the coastline. These walls would be hidden deflated underground waiting to be triggered at a moments notice. Since a tsunami triggered by a quake in the Cook Strait would only take a few minutes to hit the shore, the walls would have to inflate very quickly. To do this systems similar to those of air bags, and evacuation slides on aircraft on much larger scale could be used to inflate the walls in seconds.
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