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Guidance for FEMA's Risk Mapping, Assessment and Planning

Guidance documents provide vetted recommended approaches for FEMA's Risk Mapping, Assessment and Planning (Risk MAP) Program. These guidance documents support current FEMA standards and facilitate effective, efficient implementation of the program. All guidance documents were written to support FEMA standards and align with current regulations, but are not mandatory. Alternate approaches that comply with standards and support program objectives are acceptable.

Guidance: Hydraulics: Two-Dimensional Analysis (Dec 2020)

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.

Guidance: Shallow Flooding Analyses and Mapping (Dec 2020)

This document provides guidance to support the identification of shallow flooding hazards and the application of shallow flooding hazard determinations to National Flood Insurance Program (NFIP) products. This guidance document pertains to the study of flows for which the effects of sediment on the flow regime can be ignored. Guidance related to alluvial fan flooding, which considers sediment transport, can be accessed from Guidance Document No. 75, Guidance for Flood Risk Analysis and Mapping: Alluvial Fans.

For the purposes of the NFIP, shallow flooding is defined as flooding with an average depth limited to 3.0 feet or less where no defined channel exists.

Guidance: Profile Baseline (Dec 2020)

A Profile Baseline shows the path of riverine flood flows on the Flood Insurance Rate Map (FIRM) and is an accurate representation of the distance between cross sections, structures, nodes or grids in the hydraulic model. The Profile Baseline serves as a link between hydraulic models developed for studied reaches and the FIRM, the Flood Profiles, and the Floodway Data Table (FDT). The Profile Baseline allows users to more easily reference information in the hydraulic model and the flood profile. Profile Baselines allow users to identify the corresponding location on the FIRM given a known location on the Flood Profile or vice versa, thereby enabling the identification of a Base Flood Elevation (BFE) that is accurate and usable for processing Conditional Letters of Map Amendment; Conditional Letters of Map Revision Based on Fill, Letters of Map Amendment; and Letters of Map Revision Based on Fill and providing critical information for floodplain managers.

Guidance: MT-1 Technical (December 2020)

Guidance: MT-2 Requests (December 2020)

Guidance: Combined Coastal and Riverine Floodplain (December 2020)

Guidance: Key Decision Point (KDP) Process (Dec 2020)

The Key Decision Point (KDP) process is a formal method to document the decision to advance forward in a Flood Risk Project’s life cycle at six distinct points and to document the rationale behind these decisions. This guidance document outlines the expectations and actions required at each of the six KDPs and describes the process FEMA Regions and Headquarters will follow to document, review, and approve each KDP.

The KDPs and their documentation add a level of formality to the existing Risk MAP planning and decision-making processes already in use and provide a system of record for these decisions.

Guidance: Coastal Zone Management Act (Dec 2020)

This document provides guidance to inform procedures for documenting that the FEMA Mapping Program is consistent with the Coastal Management Plan (of the State or Territory in which a present or future flood hazard identification activity is taking place or will take place. This document is applicable to all ongoing and future regulatory flood hazard identification activities in which the scope of the study coincides partially or entirely with the coastal zone. Listed in this document are the responsibilities and documentation requirements to comply with FEMA Standard 643 to document consistency with the applicable Coastal Management Plan.

The purpose of the Coastal Zone Management Act is to protect the coastal environment from growing demands associated with residential, recreational, commercial, and industrial uses. The Coastal Zone Management Act provisions help States develop coastal management programs to manage and balance competing uses of the coastal zone. Federal Agencies, including FEMA, must follow the Federal Consistency provisions as delineated in 15 CFR part 930.

Guidance: Levee (Dec 2020)

This consolidated guidance document was prepared for FEMA, as part of the Risk MAP program, to promote sound and consistent implementation of levee-related National Flood Insurance Program (NFIP) regulations and mapping program standards that apply to levees.

This guidance document is intended to provide current information on the mapping of levees and associated flood hazards. This document captures current standards and practices and, therefore, does not address all topics related to the identification of flood hazards and risks associated with levees.

Guidance: Riverine Mapping and Floodplain Boundaries (Dec 2020)

This document provides guidance for riverine mapping and floodplains, and all the components that accompany it. FEMA prepares flood hazard mapping to create broad-based awareness of flood risk, provide data necessary for mitigation programs, and rate flood insurance for specific properties. Each floodplain or flood hazard area is divided into flood insurance rate zones that are based on the floodplain boundaries determined on a work map. Areas within the 1percentannual-chance (100-year) floodplain boundary are typically termed Special Flood Hazard Areas (SFHA). Areas between the 1- and 0.2-percent-annual-chance (500-year) floodplain boundaries are termed areas of moderate flood hazard. The remaining areas above the 0.2-percent-annual-chance floodplain are termed areas of minimal flood hazard.

Guidance: Flood Insurance Rate Map (FIRM) Graphics (Dec 2020)

This document contains guidance for the development and submission of Flood Insurance Rate Map (FIRM) panels. The graphic format for the FIRM panels can be found in the FIRM Panel Technical Reference, Format for FIRMs, Guidelines and Standards for Flood Risk Analysis and Mapping. The FIRM Panel Technical Reference is accessible through the FEMA Guidelines and Standards for Flood Risk Analysis and Mapping webpage.

Guidance: Mapping Information Platform (MIP) (Dec 2020)

The Mapping Information Platform (MIP) supports the Risk Mapping Assessment and Planning (Risk MAP) program by facilitating the production, management, and sharing of flood hazard data and maps in a digital environment. The MIP is a system of tools that integrates program and project management, data storage and retrieval, standardized quality reviews, and project tracking and reporting into one web-based application.
The MIP is a system of record for the Risk MAP program and serves as the primary portal for the capture, validation, retrieval, and storage of flood hazard mapping data produced by flood studies, and revisions and amendments (i.e., Letters of Map Change (LOMC). This document provides guidance on the various functions supported by the Studies platform within the MIP, including, user access and technical support, tools and functionality, project management and workflow activities, and data capture and dissemination. For guidance on the LOMC process MIP users should see the MT-1 Technical Guidance document.

Guidance: Flood Insurance Rate Map (FIRM) Database (Dec 2020)

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.

Guidance: Floodway Analysis and Mapping (Dec 2020)

This document provides guidance for floodway analysis, and all the components that accompany it. A floodway is a tool to assist communities in balancing development within the floodplain against the resulting increase in flood hazard. A regulatory floodway is defined as the channel of a river or other watercourse and the adjacent land area that is reserved from encroachment in order to discharge the base flood without cumulatively increasing the water-surface elevation by more than a designated height. NFIP regulations and Standard SID 69 and 70 state: “Floodway surcharge values must be between zero and 1.0 ft. If the state (or other jurisdiction) has established more stringent regulations, these regulations take precedence over the NFIP regulatory standard. Further reduction of maximum allowable surcharge limits can be used if required or requested and approved by the communities impacted.”, and “If a stream forms the boundary between two or more states and/or tribes, either the 1.0-foot maximum allowable rise criterion or existing floodway agreements between the parties shall be used.”

Guidance: Accepting Numerical Models for Use in the NFIP (Dec 2020)

For communities and mapping partners reference and information, Federal Emergency Management Agency (FEMA) maintains lists of numerical models meeting minimum regulatory requirements as a means of ensuring consistency in implementing Title 44, Chapter 1, of the Code of Federal Regulations (44 CFR) Paragraph 65.6(a)(6) of the National Flood Insurance Program (NFIP) regulations. That paragraph explains conditions under which a computer model can be used for flood hazard mapping in the NFIP.

These lists are organized by the area of responsibility of the certifying agency: Nationally Accepted Models and Locally Accepted Models. Four fall under the Nationally Accepted Models:
1. Coastal,
2. Hydrologic
3. Hydraulic, and,
4. Statistical models.

Guidance: Data Capture (Workflow Details) (Dec 2020)

This document provides guidance for submitting the data specified in the Data Capture Technical Reference. For consistency, the information was organized according to the Mapping Information Platform (MIP) Data Capture task submittal folders as specified in the Data Capture Technical Reference.

Guidance: Mapping Base Flood Elevations on Flood Insurance Rate Maps (Dec 2020)

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.

Guidance: Physical Map Revision (PMR) (Dec 2020)

The objective of the Physical Map Revision (PMR) is to update the regulatory flood hazard data and ensure that the most current and up-to-date flood hazard data, including all new studies and Letters of Map Revision (LOMRs), are incorporated into the National Flood Hazard Layer (NFHL). PMRs are processed by FEMA when a portion of a community’s flood hazards need to be revised and updating the full countywide regulatory products is not necessary. As a result, the updated flood hazard data will be used to create revised Flood Insurance Rate Map (FIRM) panels and a PMR FIRM Database.
Outlined in this guidance document is the process that Mapping Partners should follow when preparing and submitting PMRs. The roles and responsible parties for each phase are listed and the details of each responsibility are listed sequentially. A graphical representation of multiple LOMR scenarios and how to address each of them is provided in Section 3.0. A summary of the PMR scenarios is provided in Section 4.0.

Guidance: Flood Profiles (Dec 2020)

This document provides guidance to support the production of flood profiles for inclusion in Flood Insurance Study (FIS) Reports. Flood profile standards and technical specifications required to achieve the minimum level of consistency are found in the Standards for Flood Risk Analysis and Mapping and the FIS Report Technical Reference respectively. The purpose of this document is the practical application of those standards and requirements and the consistent development of the attributes not specifically addressed by those documents.

Guidance: Flood Insurance Rate Map (FIRM) Index (Dec 2020)

To support greater automation within the Risk MAP Program, FEMA is developing a tool within the Mapping Information Platform (MIP) called Automated Map Production (AMP). AMP will automate FIRM panel creation, replacing previous practices of manual cartography. The goal of AMP is to eliminate the need for manual edits or adjustments to labels on the FIRM panels and FIRM index.
AMP will read the data in a submitted FIRM database and use a series of cartographic algorithms, with established rules of hierarchy, to autogenerate FIRM panels and indexes that comply with FEMA requirements through all study stages (e.g. draft, preliminary, and final). However, AMP will not change the engineering analysis or alter the FIRM database (i.e. geodatabase; shapefiles). AMP will not fix errors in the submitted FIRM database (e.g. topology). It will continue to be the responsibility of the FIRM database producer to perform quality assurance / quality control (QA/QC) to make sure the submitted data meets all Risk MAP standards. Producers will also be expected to visually review the auto generated AMP panels to determine if they meet expectations or require changes. If updates are needed, the producer will edit the FIRM database and then resubmit to the MIP as usual to begin the process over, to include required DVT submittals.

Last updated April 6, 2021