Assessment of Floodplains in New York City

Different studies around the world have proved that the mean sea level is rising globally in the last century. The flood plains are mapped to determine the extent of flood hazard and zoning for construction, coastal protection, and evacuation if needed. In this study, the mean high high and extreme water level in New York City is analyzed to determine how the current flood plain developed by FEMA and NOAA could represent the current hazard of 100-year floods. For this purpose the sea level rise data since 1920 up to 2012 are considered including the water level data during Irene and Sandy hurricanes. The results are employed to adjust the 100-year in New York City. The flood plain boundaries are determined, and the evacuation zones are developed and compared with the current 100-year flood plain map. Moreover, an aerial map was used in this study for better assessment of current and future vulnerabilities of coastal cities including New York City. The vulnerable stations and major financial and residential regions are identified, and some suggestions are provided to reduce their vulnerabilities. Some recommendations are provided for best management practices (BMPs) application to reduce flood risks and damages. This study shows that rising sea level and high storm surges, especially following hurricane Sandy, have caused the floodplain to shift inland and more efficient flood control measures are needed.