Storm-surge barrier

Two engineers at Halcrow have come up with a conceptual design for a storm-surge barrier to protect the New York metropolitan area.

The potential for storm surges, along with rising sea levels as a result of climate change, is a growing concern in delta cities around the world. Such a surge would cause significant damage to real-estate and economic activities in and around New York.

To prevent such an event from happening, Halcrow was asked to provide ideas of what storm-surge barriers aimed at protecting the New York and New Jersey metropolitan region from severe coastal flooding might look like.

Graeme Forsyth and Dennis Padron's idea is to build a barrier that would stretch across the entrance of the outer harbour of New York and New Jersey.

The NY-NJ Outer Harbor Gateway involves a five-mile flood defence extending between the Rockaway Peninsula and Sandy Hook, plus the reinforcement of some 10 miles of the natural defences along these low-lying peninsulas.

The barrier would include two gates in the main navigation channel, with each gate having two leaves, each measuring the length of a football pitch. The barrier would also include smaller gates for two secondary navigation channels and 50 sluice gates, each 80ft (24m) across. The concept would allow for a road to run along the top of the causeway connecting the two states.

Halcrow’s concept is based on a similar project that the company has been involved with in St Petersburg, where the Russian government has funded a 15-mile-long barrier, which is due for completion in 2010.