St. Joseph County, IN Environmental Rules: Flood Elevation Requirements (2026)

291 defines the base flood elevation, or BFE, as the water surface elevation of the base flood relative to a specified datum, usually NAVD 1988, and defines freeboard as a safety factor, expressed in feet above the BFE, that compensates for unknown variables that could push flood heights higher than the calculated base flood. The county sets its freeboard at two feet by defining the flood protection grade, or FPG, as the BFE plus two feet at any point in the special flood hazard area.

294(C)(2)(b) makes that number operative: in Zone A and Zone AE, new construction or a substantial improvement of any residential structure must have its lowest floor, including any basement, at or above the FPG. 294(C)(2)(c) to let floodwater move through and equalize hydrostatic pressure on the walls, following FEMA Technical Bulletin 1. 294(C)(2)(d) apply. 291 defines a floodproofing certificate as the form used to certify compliance for non-residential structures as an alternative to elevating them to or above the FPG. 999(A), treated as a common nuisance with a daily accrual, and can put the property's flood insurance coverage at risk.