Catastrophe aversion - it is going to be expensive:

Experts: NYC sea barrier could have stopped surge

The vast destruction wreaked by the storm surge in New York could have been prevented with a sea barrier of the type that protects major cities in Europe, some scientists and engineers say. The multibillion-dollar price tag of such a project has been a hindrance, but may appear more palatable after the damage from Superstorm Sandy has been tallied.

“The time has come. The city is finally going to have to face this,” said oceanography professor Malcolm J. Bowman at Long Island’s Stony Brook University. He has warned for years of the potential for a catastrophic storm surge in New York and has advocated for a barrier.

Invited by Bowman and his colleague Douglas Hill, two European engineering firms have drawn up proposals for walling most of New York off from the sea, at a price just above $6 billion.

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