Greece, NY Environmental Rules: Flood Elevation Requirements (2026)

Section 117-17A(1) of Chapter 117 sets the residential freeboard standard: "within Zones A1-A30, AE, AH if base flood elevation data are available, new construction and substantial improvements shall have the top of the lowest floor (including basement) elevated to or above two feet above the base flood elevation," with adequate drainage paths required around structures on sloped AH-zone lots. Where no base flood elevation data exist in Zone A, Section 117-17A(2) requires the applicant's registered design professional to determine one from federal, state or other data, or from accepted hydrologic and hydraulic engineering practice, and then add the same two feet of freeboard on top.

In Zone AO, Section 117-17A(3) instead measures from the map's depth number plus one foot of freeboard, defaulting to a two-foot depth number where the map does not list one. Section 117-16C(1) extends the same two-foot buffer to building systems: new and replacement electrical, heating, ventilating, air-conditioning and plumbing equipment must sit at least two feet above the base flood elevation, or be designed to prevent water from entering and accumulating within the components during a flood. Coastal High Hazard Areas and Coastal A Zones instead follow Section 117-18, which elevates the lowest horizontal structural member to or above two feet above base flood elevation on pilings, columns or shear walls rather than fill.

Section 117-22 applies a separate, lower standard to detached garages and other accessory structures. All of these elevation standards sit on top of, not in place of, the anchoring, flood-resistant material and enclosure venting rules that Section 117-16 applies to every structure in a mapped special flood hazard area.