top of page



1007-10001 IMG_3452.JPG

What is a Letter of Map Revision?

A Letter of Map Revision (LOMR) is a letter from the Federal Emergency Management Agency (FEMA) confirming a completed project has been built to meet minimum National Flood Insurance Program (NFIP) standards for proposed hydrology changes. This in an official modification to an effective Flood Insurance Rate Map (FIRM). There are certain items required for the submittal of the LOMR to FEMA. These items include several hydraulic, structural, and general applications, a project narrative, hydraulic computations for both the existing and proposed conditions, digital models, a certified topographic work map with floodplain delineations, an annotated FIRM showing the revised area overlaid on the existing FIRM map, and notice letters to property owners within the revised floodplain area. A posting in a community newspaper is also sometimes required. 

The Application Process

Prior to the submittal to FEMA, the floodplain administrator for the regulating community in which the waterway resides must approve the LOMR application. LOMR reviews typically take up to 90 days to process pending an appeal period, and usually become effective within six months after the LOMR is submitted. The FEMA processing fees associated with a LOMR based on as-built information are typically $8,000.

bottom of page