REPORT: Nearly 300,000 New Yorkers Flooded in Sandy Lived Outside FEMA Flood Zones

New Analysis Finds 65% of Area Hit in NYC Was Not in FEMA 100-Year Flood Zone, Tallies Human & Infrastructure Toll

NEW YORK (April 8, 2014) – The Federal Emergency Management Agency’s flood maps for New York City did not identify that nearly 65 percent of the area inundated during Hurricane Sandy—home to nearly 300,000 people—was at risk from coastal flooding, according to a new analysis from the Natural Resources Defense Council. The report tallies the human toll and impact to critical infrastructure like schools and hospitals.

“Far too many New Yorkers who thought they were outside of the danger zone were hit with a surprise attack from Mother Nature when Hurricane Sandy flooded homes, businesses, hospitals, schools and nursing homes across the city,” said NRDC senior scientist Kim Knowlton. “We can do more to prepare and to protect people’s health. By updating its maps to better predict future flood risks in a changing climate, FEMA can help more people stay out of harm’s way—and help the whole city prepare better and recover faster—when the next storm hits.”

The new report, Preparing for Climate Change: Lessons Learned for Coastal Cities from Hurricane Sandy, finds that FEMA—by relying on flood maps that were nearly 30 years old—substantially underestimated the people and places at-risk in New York City, leaving the city and hundreds of thousands of residents unprepared when Hurricane Sandy inundated their homes in the fall of 2012.

Particularly troublesome is the fact that vulnerable populations—including young children, elderly and economically disadvantaged residents—may not have realized they were at risk of flooding and therefore may not have been ready to evacuate or take other critical preparations, such as stocking extra food, water and medications.

“We must not squander Sandy’s call to get ready for more rising seas, and recognize the importance of informed flood preparedness,” said Knowlton.

A detailed breakdown of the people and critical infrastructure unexpectedly flooded follows. The full report—including a series of related maps—can be found here:


The report found that the following New York City populations were not included in FEMA’s maps of areas at-risk of flooding, but were inundated during Hurricane Sandy:

  • Nearly 300,000 New Yorkers in total
  • Nearly 90,000 people with limited economic means to recover
  • More than 59,000 people who were likely to need help to get out of harm’s way (specifically more than 16,000 children under 5 and more than 43,000 people over 65 years old)


The total flooded area was 65 percent bigger in Sandy than FEMA expected according to its maps, with Brooklyn and Queens experiencing the majority of the unexpected flooding. A number of these inundated buildings were providing services for children, the elderly and the sick, or serving other important functions to keep the city operating safely. This damage can pose serious risks to public health and the environment.

Specifically, the following structures flooded during Sandy but were not previously identified by FEMA as vulnerable to flooding:

  • 80 schools
  • 74 daycare centers or Head Start facilities
  • 28 public housing buildings, home to over 61,000 residents
  • 22 residential facilities providing social services for adults, families or children (such as homeless shelters, group homes and assisted living facilities)
  • 18 hospitals or nursing homes
  • 9 senior centers
  • 4 wastewater treatment plants, causing 600 million gallons of sewage to overflow into area waterways


FEMA is tasked with evaluating and mapping the nation’s vulnerability to flooding. This information guides planning and preparedness for storms like Sandy. It helps cities decide where to build critical infrastructure, such as schools and hospitals. It helps business-owners decide where to set up shop. It helps people make informed choices to stay out of harm’s way and decide where to live.

Far too many learned the hard way that FEMA’s maps were out-of-date when Sandy hit. And, by law, FEMA is now required to update its flood maps to reflect the future impacts of climate change, including sea level rise, on flood risk.

Unfortunately, preliminary updated flood maps for New York City, which FEMA released in December 2013, still do not account for these climate change impacts. As a result, they continue to underestimate the people, buildings and critical infrastructure at risk from flooding during future storms.

Scientists are estimating that flooding on a scale similar to what we saw during Sandy could occur every other year within less than a century. Therefore, it’s critical that FEMA use the best available science to provide the most informed predictions possible of the people and areas at risk moving forward.

“By supporting up-to-date climate change preparedness strategies, FEMA can further help save lives, save dollars, and create healthier, more secure communities,” said Knowlton.


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