Letter of Map Amendment (LOMA)

Overview of Maps and Map Change Processes for Properties

As part of its administration of the National Flood Insurance Program (NFIP), the Federal Emergency Management Agency (FEMA) publishes flood hazard maps, called Flood Insurance Rate Maps, or FIRMs. The purpose of a FIRM is to show the areas in a community that are subject to flooding and the risk associated with these flood hazards. One of the areas shown on the FIRM is a Special Flood Hazard Area (SFHA). The SFHA is the area that has a 1-percent or greater chance of flooding in any given year; this area is also referred to by some as the 1-percent-annual-chance floodplain, base floodplain, or the 100-year floodplain. The flood hazard and risk information presented on the FIRMs is the result of engineering studies that are performed by engineering companies, other Federal agencies, or communities, which are reviewed for compliance with FEMA guidelines and approved by FEMA.

FEMA uses the most accurate flood hazard information available and applies rigorous standards in developing the FIRMs. However, because of limitations of scale or topographic definition of the source maps used to prepare a FIRM, small areas may be inadvertently shown within an SFHA on a FIRM even though the property (legally defined parcel(s) of land, structure[s]) is on natural ground and is at or above the elevation of the 1-percent-annual-chance flood. This elevation is most commonly referred to as the Base Flood Elevation, or BFE. Such cases are referred to as “inadvertent inclusions.”

For other small areas, earthen fill may have been placed during construction, thereby elevating a small area within the SFHA to an elevation that is at or above the BFE. This construction may have taken place during the time the engineering study was being performed or subsequent to that study. Because of the limited extent of the elevated area and the limitations of the map scale, it may not have been possible for FEMA to show this area as being outside the SFHA and so these areas have been incorrectly included in the SFHA on the FIRM.

Recognizing that these situations do occur, FEMA established administrative procedures to change the designation for these properties on the FIRM. These processes are referred to as the Letter of Map Amendment, or LOMA, process and the Letter of Map Revision Based on Fill, or LOMR-F, process. Through these processes, an individual who owns, rents, or leases property may submit certain mapping and survey information to FEMA and request that FEMA issue a document that officially removes a property and/or structure from the SFHA. In most cases, the applicant will need to hire a Licensed Land Surveyor or Registered Professional Engineer to prepare an Elevation Certificate for the property. Upon receiving a complete application forms package, FEMA will normally complete its review and issue its determination in 4 to 6 weeks.