Clarkstown, NY Hurricane Preparedness: Flood Elevation (2026)

" Where a property sits in Zone A without a specified base flood elevation, § 146-6C(1)(b) requires the applicant to obtain federal, state or other data plus two feet of freeboard, or have a registered design professional calculate the base flood elevation using accepted hydrologic and hydraulic methods, plus freeboard. In Zone AO, the lowest floor must be elevated above the highest adjacent grade at least as high as the FIRM's depth number plus two feet of freeboard, or three feet if no depth number is listed.

Manufactured homes get their own standard under § 146-6E: the bottom of the chassis frame must be elevated to or above two feet above the base flood elevation on a permanent, anchored foundation. Applicants must submit the proposed elevation with their floodplain development permit application under § 146-5C(1), and once the lowest floor is complete, the permit holder must submit an as-built elevation certified by a licensed professional engineer or surveyor to the local administrator, the Director of Engineering and Facilities Management.