These archived guidelines and standards have been superseded by more recent statutory and regulatory requirements. Go back to current guidelines and standards.
Search below for archived copies of past guidelines and standards for flood risk analysis and mapping activities under the Risk MAP program.
This policy updates and supersedes the Standards for Flood Risk Analysis and Mapping – FP 204-078-1 (Rev 11) approved on Dec. 22, 2020.
FEMA Policy #204-078-1
This policy updates and supersedes the Standards for Flood Risk Analysis and Mapping – FP 204-078-1 (Rev 10) approved on Dec. 11, 2019.
FEMA Policy #FP 204-078-1 (Rev 10)
This policy updates and supersedes the Standards for Flood Risk Analysis and Mapping – FP 204-078-1 (Rev 9) approved on April 29, 2019.
This document discusses 2-D modeling as it pertains to National Flood Insurance Program (NFIP) regulatory products. NFIP regulatory products are used to determine if a structure is located in a Special Flood Hazard Area (SFHA), set the flood insurance risk premium rate, and enforce appropriate floodplain management regulations. The 1-percent-annual-chance flood is a regulatory standard for the NFIP. Flood Insurance Rate Maps (FIRMs) are regulatory maps, where the 1-percent and in some instances 0.2-percent-annual chance floodplain boundaries are shown. If a flood insurance study includes regulatory floodways, additional information such as average flood velocity and cross sectional area are provided at some modeled cross sections as well. It is important to note that although some communities might choose to use FIRMs as a flood risk management tool, the main purpose of these maps is still flood insurance rate determination and floodplain management. Therefore, the most critical information shown on FIRMs are the flood elevations associated with the 1-percent-annual-chance discharges in the flooding sources. This document is not a technical manual or reference for 2-D modeling techniques.
This document contains guidance for the development and submission of Flood Insurance Rate Map (FIRM) Databases. A full description of the standards and schema for the content of the FIRM Database can be found in the FIRM Database Technical Reference.
This document provides guidance to Production & Technical Services (PTS) Mapping Partners for Letter of Map Revision (LOMR) incorporation activities as part of Flood Risk Projects. The application of the guidelines in this document will facilitate data transfers between the PTS MT-2 teams, the PTS National Flood Hazard Layer (NFHL) teams, and the PTS Flood Insurance Rate Map (FIRM) and Flood Insurance Study (FIS) production teams. Topics covered by this guidance include MT-2 post-processing procedures, the incorporation of “mappable” LOMRs affecting the FIRM or FIS Report materials during the Data Development through Effective Issuance PTS production stages of a Flood Risk Project, and guidance on the re-incorporation of finalized (effective-ready) FIRM Database data back into the NFHL.
Water-surface elevations of the 1-percent annual chance (base) flood are called Base Flood Elevations (BFEs). These BFEs may be designated on the Flood Insurance Rate Map (FIRM) using specific BFE lines (as done historically) or at 1D model cross sections/2D model evaluation lines with the appropriate elevation labels. BFEs are placed on the FIRM to assist users in determining the elevation of the 1-percent-annual-chance flood elevation anywhere within the floodplain. For more detailed information on BFE determinations, users should reference the base flood profile in the Flood Insurance Study report, where applicable.
