Problem DescriptionHurricane Sandy vividly demonstrated the city’s vulnerability to coastal storms. With 520 miles of coastline, New York City has been exposed to these risks since its founding. Over the past 400 years, the city’s shoreline has been developed and modified in ways that have contributed to increased risks from coastal storms. Now, a changing climate is adding to the risks. Our current understanding of flood risk comes from FEMA and its Flood Insurance Rate Maps (FIRMs). These maps were first adopted in 1983 and showed that 33 square miles of the city were in the 100-year floodplain, which includes 218,000 people. Updated maps will show approximately 400,000 people currently in the 100-year floodplain.
These maps do not include projections on rising sea levels. In addition to the approximately 1.1 feet of sea level rise the city has experienced since 1900, current mid-range projections show sea levels will rise another one to two feet by 2050 and two to four feet by 2100. The NPCC shows that due to sea level rise, these floodplains are expected to continue growing and increase the frequency and intensity of citywide flooding. In fact, the floodplain projections provided by the NPCC show 71 square miles will be in the 100-year floodplain in 2050, which includes approximately 808,900 people. This is a 42 percent increase.
Alarming as they are, these projections largely assume that no action will be taken to mitigate this risk. However, the City is continuing to act to reduce the impacts of climate change. We will expand our efforts to adapt coastal communities to the evolving risks of climate change, including flooding and sea level rise.
Solution StageOne of the 7 stages of an innovation. Learn more
|STAGE||SPECIALIST SKILLS REQUIRED||EXAMPLE ACTIVITIES||RISK LEVEL AND HANDLING||FINANCE REQUIRED||KINDS OF EVIDENCE GENERATED||GOAL|
|Developing and testing3||Mix of design and implementation skills|
|A stronger case with cost and benefit projections developed through practical trials and experiments, involving potential users||Demonstration that the idea works, or evidence to support a reworking of the idea|