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# Numerical Models Meeting the Minimum Requirements of the National Flood Insurance Program

                            - English 

This page provides a list of nationally and locally accepted models that meet National Flood Insurance Program (NFIP) requirements for flood hazard mapping activities, technical documentation for acceptable models and models no longer acceptable. This page is intended for engineers, surveyors, floodplain managers and FEMA mapping partners.

All computer models referenced from this web page have met the requirements of Subparagraph 65.6(a)(6) of the NFIP regulations that explain conditions by which a computer model may be used for flood hazard mapping. For further information on these regulations and to learn how to get a model added to this list, please refer to the Policy for Accepting Numerical Models for Use in the NFIP.

FEMA has also developed the Conditional Permission to Disclose Source Codes and Users Manual (2002) and the Clarification of NFIP Criteria for Certification of Coastal, Hydrologic and Hydraulic Models (2001). For further information on the FEMA policy of accepting GIS enhanced hydrology and hydraulics modeling tools, please refer to Memo: Policy for Accepting GIS Tools for Flood Hazard Mapping in the NFIP (August 2001).

The resources below include the current list of acceptable models, which have been separated into nationally and locally accepted categories; supporting technical documentation for certain acceptable models and a list of numerical models which FEMA no longer accepts for NFIP usage.

## Current Nationally and Locally Accepted Models

### Coastal Models

Includes  coastal storm surge, coastal wave height and coastal wave effect models.

### Hydrologic Models

Includes single event and continuous event simulation models.

### Statistical Models

Includes nationally and locally accepted models.

### Hydraulic Models

Includes one-dimensional steady flow, one-dimensional unsteady flow, two-dimensional steady/unsteady flow and floodway analysis models. 

Please reference Policy for the use of HEC-RAS in the NFIP .

## Supporting Technical Documentation for Acceptable Models

Floodway Analysis for Stormwater Modeling and Management (SWMM) Models (2001)

Floodplain Modeling Manual: HEC-RAS Procedures for HEC-2 Modelers (2002)

## Numerical Models No Longer Accepted

Please visit the Numerical Models No Longer Accepted by FEMA for NFIP Usage page for a list of unaccepted models.

Last updated January 7, 2022

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