Underwater – A Report on the Threat of Sea Level Rise in the New York City Metro Area

Under Water How Sea Level Rise Threatens the Tri-State Region, A Report of The Fourth Regional Plan, December 2016.

Coastal regions around the world are struggling to adjust to the gradual but relentless encroachment of ocean waters caused by climate change. The New York metropolitan area, with 23 million residents and some 3,700 miles of tidal coastline, faces a severe threat from sea level rise, yet relatively little has been done to address the inevitable permanent inundation of buildings, infrastructure and communities.

Permanent flooding from sea level rise is different than the intermittent flooding from storm surge or precipitation. Intermittent flooding recedes once a storm passes while sea level rise flooding is permanent and can be expected to encroach further inland over time. Sea level rise not only permanently alters the coast line. It also widens the area vulnerable to storm surge.

This report identifies the places in the New York, New Jersey and Connecticut metropolitan area that are most at risk of being permanently flooded, and describes the effects of 1, 3 and 6 feet of sea-level rise on neighborhoods, employment centers and infrastructure. Taking into account the latest scientific findings on sea level rise and climate change, the study finds that many of the major resilience policies, plans and projects under development today fall short of adequately addressing the long term, existential threat of permanent flooding from sea level rise.