Shoreline Expansion in City's Proposal for Lower Manhattan Flood Resiliency

Proposed interim measures to protect the Seaport and parts of the Financial District include the deployment of water-filled dams in the event of a storm and four-foot-high sand-filled barriers, at left, that would remain in place. The barriers are intended to handle anticipated storm surges over the next 10 years. Rendering: NYC Economic Development Corp.

Mar. 15, 2019

In what he calls “one of the most complex environmental and engineering challenges our city has undertaken,” Mayor de Blasio is calling for a flood protection plan for a large swath of Lower Manhattan.

“Today we announce a plan unlike anything that’s been done before in terms of its scope, in terms of its impact,” de Blasio said on Thursday as he unveiled the citys Lower Manhattan Coastal Resiliency Plan. “This is a plan that will protect Lower Manhattan for the remainder of this century.”

Boldest among the proposed initiatives to counter future storms and higher sea levels is the $10 billion expansion of the East River shoreline, up to 500 feet or about two city blocks, that would extend from the Brooklyn Bridge to the Battery. According to the study, the low-lying area, only eight feet above sea level, contains massive underground infrastructure—utilities, sewers and subways—that can’t be protected any other way.

In the meantime, the city plans to spend $500 million on four interim flood protection projects that include grassy berms in parks, and removable barriers that can be installed when needed.  

The study does not include resiliency measures for Tribeca. Superstorm Sandy flooded much of the neighborhood from Greenwich Street out to the piers, causing one drowning death and heavy damage.

“There is no resiliency plan in place for the entire west side of Lower Manhattan between Chambers and Canal Street,” said Alice Blank, chair of Community Board 1’s Environmental Protection Committee.

“How could the city deliver a comprehensive plan when it’s not comprehensive,” Blank noted. “To introduce this as the Lower Manhattan Coastal Resiliency Plan is a little scary because we seem to be missing a fair amount in that plan.”

By this year’s hurricane season, the city intends to have available temporary protections for the Seaport and parts of the Financial District that include water-filled bladders called Tiger Dams and modular, sand-filled HESCO barriers. At the Battery, the city expects to raise the wharf and esplanade and build a berm or other protective barrier. And the Battery Park City Authority is already in the midst of a $134 million resiliency plan to reconstruct the Battery Park City esplanade and open space, including the ball fields, with construction to begin next year. The Two Bridges area would have deployable “flip-up” barriers.

Over the next two years, the Mayor’s Office of Recovery and Resiliency and the city’s Economic Development Corp. will develop a master plan for the shoreline extension. This spring the EDC said it will begin a “robust” community engagement process that will influence the size of the East River extension and what will go on it.

Anthony Notaro, chair of Community Board 1, called the land extension “a bold plan,” but one that lacks funding and has big permitting hurdles ahead.

“I’m sure the community board is going to have to study it and have lots of debate about it,” Notaro said. But implementation of the plan “may be a decade away, and that’s really a problem.”