New York City Mayor Bill de Blasio has revealed a plan to protect Lower Manhattan from rising sea levels by surrounding it with earthen berms and extending its shoreline by as much as 500 feet (152 meters).
The plan piggybacks on a climate resilience study released by the city today, which found that roughly 37 percent of Lower Manhattan properties will be at risk from storm surges in the next 30 years.
And by 2100, it says this will rise to almost 50 percent.
De Blasio’s new plan aims to combat an estimated six feet of sea level rise that’s expected to encroach upon the city by the end of the century.
In addition to fortifying most of Lower Manhattan with grassy berms and removable barriers, which would cost roughly $500 million, the city has proposed adding more land to the lowest-lying areas, from the Brooklyn Bridge to the Battery.
Doing this would take several years, and could cost as much as $10 billion.
The Democratic mayor announced the plan Thursday after previewing it in New York Magazine.
Officials have been developing schemes to fortify New York City’s waterfront ever since Superstorm Sandy destroyed thousands of homes and businesses in 2012.
In addition to storm surges, groundwater table rise is also projected to put 7 percent of buildings at risk of destabilization, and put streets and underground utilities at risk of corrosion and water infiltration.