FEMA - Change Special Flood Hazard Zone designation

If your project proposes to change your Federal Emergency Management Agency’s (FEMA) Special Flood Hazard Zone designation, FEMA has created a process of preliminary approval with a Conditional Letter of Map Revision (CLOMR), and final approval with a Letter of Map Revision (LOMR) prior to changing the maps. FEMA requires the review and approval of the Local Floodplain Administrator prior to submittal to FEMA.

What is needed to make an application? Copies of the following items are required to be submitted digitally to the Permit Center.


All items required in the LOMR application listed below, without the as-built plans, and the following CLOMR specific items:

  • PROPOSED PLANS: Proposed plans, certified by a registered Professional Engineer, for all the project elements.
  • ENDANGERED SPECIES ACT COMPLIANCE: Documentation of compliance with the ESA Requirements.
  • 65.12 REGULATORY REQUIREMENTS: If the Base (1-percent-annual-chance) Flood Elevation (BFE) increases greater than 0.00 foot as a result of encroachment within a floodway, or 1.0 foot within Zone AE that has no floodway/Zone A, between the pre-project (existing) conditions and the proposed conditions as a result of the proposed project, please submit:
    • Certification that no structures are affected by the increased BFE;
    • Documentation of individual legal notice to all affected property owners, explaining the impact of the proposed action on their property; and
    • An evaluation of alternatives that would not result in an increase in BFE.


  • NARRATIVE: A written description about the purpose of the request and the scope of the proposed/as-built project and the methodology used to analyze the project effects.
  • MT-2 APPLICATION FORMS: Completed forms applicable to your request. Ensure that MT-2 Form 1 was signed by the requester, certifying engineer, and each community affected by the revision.
  • HYDROLOGIC ANALYSIS: If applicable, provide a FEMA acceptable hydrologic analysis in digital format, drainage area map and associated backup information (e.g., calculations used to determine lag time, CN and loss values as well as land use and soil maps). FEMA-acceptable models can be accessed at https://www.fema.gov/flood-insurance.
  • HYDRAULIC ANALYSIS: A FEMA acceptable hydraulic analysis in digital format. FEMA-acceptable models can be accessed at https://www.fema.gov/flood-insurance​.
  • CERTIFIED TOPOGRAPHIC WORK MAP: A certified topographic work map that meets the mapping requirements outlined in MT-2 Form 2. If available, please provide digital Computer-Aided Design (CAD) or Geographic Information System (GIS) data that is spatially referenced.
  • ANNOTATED FIRM: A revised FIRM, at the scale of the effective FIRM, which shows the revised boundary delineation of the base floodplain, 0.2-percent-annual-chance floodplain, and regulatory floodway and how it ties into the boundary delineation shown on the effective FIRM at the downstream and upstream ends of the revised reach.
  • MEET 65.10 REQUIREMENT: All of the data requirements outlined in Section 65.10 of the NFIP regulations if the request intends to show that a berm/levee/flood wall provides flood protection.
  • OPERATION AND MAINTENANCE PLAN: An officially adopted maintenance and operation plan if the request involves a berm, levee, flood wall, dam, and/or detention basin project.
  • AS-BUILT PLANS: As-built plans, certified by a registered Professional Engineer, for all the project elements.
  • FLOODWAY NOTICE MAILING LIST: A mailing list of all affected property owners such that the County can provide a floodway public notice or a statement in compliance with NFIP regulation Subparagraph 65.7(b)(1) if the revision results in changing or establishing floodway boundaries.

The approved application will be sealed with an APPROVED stamp and placed in the record.​​​​

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