FEMA has established administrative procedures for changing effective Flood Insurance Rate Maps (FIRMs) and Flood Insurance Study (FIS) reports based on new or revised scientific or technical data. A physical change to the affected FIRM panels and portions of the FIS is referred to as a ''physical map revision.'' When FEMA revises a community's FIRM, the community is required to amend its floodplain management regulations within 6 months of being notified to incorporate the new data.Changes can also be made by a Letter of Map Change (LOMC).
There are several categories of LOMCs, depending on the complexity of the changes.
A Conditional Letter of Map Revision (CLOMR) is not a revision to an NFIP map.
All requests for changes to effective maps, other than those initiated by FEMA, must be made in writing by the Chief Executive Officer (CEO) of the community or an official designated by the CEO.
National Flood Insurance Program Requirements
- Part 65 - Identification and mapping of special hazard areas