The 2010 Rising Currents project was a multi-disciplinary study that produced proposals for addressing the vulnerability of New York's waterfront. New York harbor was once lined with wetlands and full of reeflike oyster beds that cushioned the shoreline from storm surges. The Rising Currents exhibition at the Museum of Modern Art illustrated how reintroducing green space and developing greener edges at the waterfront could serve as stormwater and storm-surge protection. Softer edges would transform and enhance the quality of life in the city, says Adam Yarinsky, principal at the firm Architectural Research Office and a participant in the study. “I'm glad that in the debate after Sandy there's a growing consensus that there needs to be a range of solutions—not just hard, engineered infrastructure,” Yarinsky says.

In 2009, the American Society of Civil Engineers asked several engineering firms to look at ways to protect New York City from storm surges. Larry Murphy and Thomas Schoettle of CDM Smith proposed a barrier at Arthur Kill, the narrows between Staten Island and New Jersey. The scheme would utilize a damlike structure with locks to accommodate boat and ship traffic. The barrier would also incorporate a pedestrian/bicycle bridge to make it accessible as a transportation and recreational amenity.

The firm employed a similar concept of combining infrastructure with recreational components in Singapore's Marina Barrage, completed in 2008. Built primarily to create a reservoir and to control the water level in the marina, the barrage has the long-term benefit of protecting the area from storm surges and sea-level rise. It also acts as a pedestrian bridge across the marina channel. The structure culminates at one end with a swirling turf-roofed pavilion that houses enormous pumps, which are activated during heavy rains at high tide.

In terms of hard infrastructure, New Orleans is the flagship in the U.S. for the barrier-and-pump method of keeping water out. This defensive approach is based on the historic Dutch dike system. After Hurricane Katrina breached the levees in 2005, the system got a $14.5 billion revamp and held up against the ravages of Hurricane Isaac, whose surge height rivaled that of Katrina. But the New Orleans architecture firm Waggonner & Ball advocates for an approach that combines defensive measures with enhancing natural systems.

The firm partnered with experts from the U.S. and the Netherlands to form the team that won the 2012 Greater New Orleans competition to design a new water-management plan for the city. The scheme promotes alternatives to the pump-and-pipe method by proposing ways to slow and control stormwater while reintroducing park-lined waterways.