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Software for Flood Mapping


The U.S. Army Corps of Engineers (USACE) Hydrologic Engineering Center's River Analysis System (HEC-RAS) computer program supersedes its HEC-2 computer program, which was widely used in the preparation of studies and restudies for the National Flood Insurance Program (NFIP).

FEMA has adopted the guidance that hydraulic analyses for newly contracted studies and restudies of entire watersheds (with detailed HEC-2 hydraulic analyses) should be conducted using the HEC-RAS program instead of the HEC-2 program. This floodplain modeling manual is prepared as a guide to introduce the HEC-RAS Version 3.0 modeling procedures to engineers who have experience in preparing floodplain models with the HEC-2 computer program.

Download HEC-RAS

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cHECk-RAS, Version 2.0.1

cHECk-RAS is a program designed to verify the validity of an assortment of parameters found in the USACE HEC-RAS hydraulic modeling program. In cHECk-RAS Version 2.0.1, updates have been made to modernize the program code base, redesign the program interface to be more intuitive and user-friendly, improve and update existing messages generated by the program, develop new messages generated by the program and enhance ‘Help’ and reporting functions.

Download cHECk-RAS version 2.0.1

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User's Manuals and Additional Guidance


RASPLOT is a computer program developed by FEMA which allows the user to create flood profiles through the automatic extraction of data from Hydraulic Engineering Centers River Analysis System (HEC-RAS) hydraulic modeling files. Flood profiles are required for inclusion in the Flood Insurance Study (FIS) reports which usually accompany the Flood Insurance Rate Map (FIRM) for communities participating in FEMA’s National Flood Insurance Program.

Download RASPLOT

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For First-Time RASPLOT Users

After clicking the above “Download RASPLOT” button, users must also click on the “RASPLOT Installation File” to complete RASPLOT installation. If the RASPLOT Installation File does not facilitate successful installation of RASPLOT to your computer, please download the “RASPLOT Back-up File” instead.  

User's Manuals and Additional Guidance

Quick-2, Version 2.0

Quick-2, Version 2.0, is the latest version of a hydraulic analysis program used to compute water-surface elevations in open channels of all types. Quick-2, Version 2.0 is designed to only run on Operating Systems (OSs) through Windows 98. FEMA does not plan to upgrade for OsS XP and beyond. FEMA suggests using HEC-RAS software for users experiencing issues using version 2.0 on later OSs.

Quick-2, Version 2.0 Tutorial

National Streamflow Statistics (NSS)

To provide simple methods of estimating streamflow statistics, the U.S. Geological Survey (USGS) has developed and published regression equations estimating the magnitude and frequency of floods for every state, the Commonwealth of Puerto Rico, and a number of metropolitan areas in the United States, and regression equations for estimating other streamflow statistics are available for many states.

Download National Streamflow Statistics

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National Streamflow Statistics replaces the National Flood Frequency (NFF) software. NSS contains all of the NFF functionality and equations as well as low flow and other probability equations. The NFF program and database have not been changed since 2004 and will no longer be updated or supported.

Coastal Hazard Analysis Modeling Program (CHAMP)

Coastal Hazard Analysis Modeling Program (CHAMP) is a Windows-interfaced Visual Basic language program that allows the user to enter data, perform coastal engineering analyses, view and tabulate results and chart summary information for each representative transect along a coastline within a user-friendly graphical interface. With CHAMP, the user can import digital elevation data; perform storm-induced erosion treatments, wave height analyses and wave runup analyses; plot summary graphics of the results and create summary tables and reports in a single environment.

User's Manuals and Additional Guidance

RUNUP, Version 2.0

RUNUP, Version 2.0, is a DOS-based program for wave runup computation. This program uses stillwater elevation, shore profile and roughness and incident wave condition input information to compute a wave runup elevation that is consistent with the most detailed guidance currently available.

User's Manuals and Additional Guidance

Wave Height Analysis for Flood Insurance Studies (WHAFIS), Version 4.0

Wave Height Analysis for Flood Insurance Studies (WHAFIS), Version 4.0, is a DOS-based program that uses representative transects to compute wave crest elevations in a given study area. Transects are selected considering major topographic, vegetative and cultural features. WHAFIS uses this and other input information to compute an appropriate depth-limited wave height at the seaward end of each transect.

User's Manuals and Additional Guidance

WRAS - HEC-RAS Conversion Program

WRAS is a conversion program developed by the Natural Resources Conservation Service (NRCS) that takes existing WSP2 data sets and converts them to HEC-RAS format for import into HEC-RAS. WRAS requires Windows 95 or higher and approximately 12 megabytes of hard disk storage.

Download WRAS

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