New York state authorities are being urged to consider building a storm surge barrier to prevent flooding.
The plan is a key recommendation of the NYS2100 Commission, appointed by New York state governor Andrew Cuomo following the destruction caused by Superstorm Sandy in October.
The storm caused widespread damage, killed 43 New Yorkers and flooded major road and subway tunnels linking Manhattan with other parts of the city. The commission investigated options for strengthening the state’s infrastructure and making it more resilient.
The commission said the state should conduct a “comprehensive assessment of the need, feasibility, costs, and impacts of storm surge barriers as a first line of defence” for New York harbour.
However, it admitted that the flood defence barrier “would have to be much more complex than those in London and Saint Petersburg”, because of the harbour’s size, geography, and hydrology.
This means at least two and possibly three separate barriers would have to be built.
The commission estimated that construction costs could be anything from $7bn (£4.35bn) to $29bn (£18bn).
Among its recommendations for improving the resilience of New York State’s transport systems was the creation of a “transportation lifeline network” of tunnels, bridges, highways, rail facilities and airports that was “physically able to withstand the impacts of severe events”.
The commission also recommended establishing an infrastructure bank to “coordinate, allocate, and maximise investment in the construction, rehabilitation, replacement, and expansion of infrastructure”.