De Blasio unveils $10bn scheme to build new chunk of Manhattan to combat climate change

• Mayor wants to protect Wall Street from floods and rising seas
• Plans to cost $10bn but federal funds might not be available

Bill de Blasio, the mayor of New York, has announced a radical plan to meet the "existential threat" of climate change by constructing a new section of Manhattan , extending hundreds of feet out into the narrow East river, in order to protect Wall Street and other downtown areas.

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