LOMA (Letter of Map Amendment)
A Letter of Map Amendment is a FEMA determination that a specific property or structure, on natural ground, sits above the Base Flood Elevation and is therefore removed from the special flood hazard area. It relies on surveyed elevations. Where fill has raised the ground, a different process, the LOMR-F, applies. A LOMA changes insurance and regulatory status but not the physical flood risk.
The full guide · Environmental & physical riskCan You Build a Data Center in a Floodplain?How FEMA flood zones, floodways and base flood elevations affect data center sites, what it takes to build near a floodplain, and how to screen flood risk.