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

Where no base flood elevation data exist in Zone A, the lowest floor must instead sit at least three feet above the highest adjacent grade, and in Zone AO it must clear the highest adjacent grade by at least two feet above the depth number printed on the community's Flood Insurance Rate Map, or two feet if no depth number is shown. Nonresidential buildings follow the same two-foot freeboard for the lowest floor, or may instead be floodproofed watertight to two feet above the base flood elevation with walls substantially impermeable to water and components able to resist hydrostatic and hydrodynamic loads, certified by a licensed engineer or architect.

Manufactured homes placed in Zones A1-A30, AE, or AH must sit on a permanent foundation with the lowest floor elevated to or above two feet above the base flood elevation and be securely anchored against flotation and lateral movement. Any fully enclosed area below the lowest floor that is used only for parking, access, or storage must have flood vents totaling at least one square inch of net opening per square foot of enclosed area, with the bottom of each opening no higher than one foot above the adjacent grade, so floodwater can enter and exit without collapsing the walls.