The Department of Buildings is the New York City’s Floodplain Administrator. Any building in the floodplain (including certain properties located in X Zones) must comply with the applicable flood resistant construction requirements outlined in Appendix G of the 2014 Building Code. An existing building in the floodplain that is performing a substantial improvement or was substantially damaged, must be constructed or altered to fully comply with the flood zone regulations as if it were newly built. For residential buildings, this includes elevating habitable spaces and filling in basements or cellars to grade. If you have any questions, please contact DOB at email@example.com. Also, DOB has homeowner nights at their borough offices every Tuesdays, no appointment necessary.