U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov

A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS

A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites..

alert - warning

This page has not been translated into Tagalog. Visit the Tagalog page for resources in that language.

Hydraulic Numerical Models Meeting the Minimum Requirement of National Flood Insurance Program

National Models

Local Models

Other Models

No Longer Accepted Models

This page provides a list of nationally and locally accepted coastal models that meet National Flood Insurance Program (NFIP) requirements for flood hazard mapping activities. This page is intended for engineers, surveyors, floodplain managers and FEMA mapping partners.

Disclaimers

  • This website lists models, DHI Water & Environment where the compliance with the requirements of Code of Federal Regulations Title 44 (44 CFR) Revision of Base Flood Elevations Determinations 65.6(a)(6) has been previously demonstrated for use in FEMA flood hazard studies and/or mapping efforts. The lists include models that professional engineers can use to perform engineering analysis and mapping for flood insurance studies, however a model’s inclusion on this list does not indicate whether its approval or certification is current as to any other governmental agency. Professional engineers are ultimately responsible for the appropriate application and accuracy of the results.
  • FEMA is not responsible for technical support or accuracy of the results and has not evaluated the technical soundness of the models independently.
  • This list cannot be used as a marketing tool explicitly or implicitly anywhere.
  • FEMA updates its list as necessary. However, the accuracy of this list is not guaranteed. It is highly recommended that model selection is discussed with FEMA before undertaking or initiating any analysis intended to be submitted to FEMA.
  • FEMA provides this list for reference only and, in doing so, does not endorse any non-federal products, companies or services. If you believe that any information provided on this page is inaccurate, please contact FEMA at 1-877-FEMA MAP (1-877-336-2627).

Current Nationally Accepted Hydraulic Models

Hydraulic Models: Determination of Water-Surface Elevation for Riverine Analysis

Please reference the following memorandums on the use of HEC-RAS for NFIP purposes. Note that the memorandums are periodically updated and should be read each time before referring to the below chart.

One-Dimensional Steady Flow Models

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: cHECk-RAS

Developed By

Federal Emergency Management Agency (FEMA)

Available From

Federal Insurance and Mitigation Administration
500 C Street, SW
Washington, DC 20472

cHECk-RAS

Public Domain

Yes

Comments

cHECk-RAS is a program designed to verify the validity of an assortment of parameters found in the U.S. Army Corps of Engineers (USACE) HEC-RAS hydraulic modeling program. cHECk-RAS utilizes information generated by HEC-RAS (all versions through the latest version, 4.1.0.) This program can run only on computers with Microsoft Windows XP, Vista, or 7 (32- or 64-bit) operating systems. The current version of cHECk-RAS in use is 2.0.1.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: Culvert Master v. 2.0 (September 2000), and up

Developed By

Bentley Systems

Available From

Bentley Systems
685 Stockton Drive
Exton, PA 19341

Public Domain

No

Comments

Compute headwater elevations for circular concrete and RCB culverts for various flow conditions.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: HEC-RAS 3.1.1 and up

Developed By

U.S. Army Corps of Engineers (USACE)

Available From

Water Resources
Support Center
U.S. Army Corps of Engineers
Hydrologic Engineering Center
609 Second Street
Davis, CA 95616-4687

Public Domain

Yes

Comments

For water surface elevation difference due to use of different HEC-RAS versions, refer to FEMA Memorandum HEC-RAS Version Updates (August 17, 2004)

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: HEC-RAS 5.0.0 and up (Mar 2016)

Developed By

U.S. Army Corps of Engineers (USACE)

Available From

Water Resources
Support Center
U.S. Army Corps of Engineers
Hydrologic Engineering Center
609 Second Street
Davis, CA 95616-4687

Public Domain

Yes

Comments

The River Analysis System is able to model excess precipitation applied directly to a 2D flow area. Losses and infiltration are not currently able to be computed within RAS, so excess precipitation should be determined using separate approved hydrologic methods or software (such as HEC-HMS) prior to applying it within the model domain.

Calibration runs against available gage or other study data should be used wherever possible to validate model output.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: HEC-2 4.6.2 1 (May 1991)

Developed By

U.S. Army Corps of Engineers (USACE)

Available From

Water Resources
Support Center
U.S. Army Corps of Engineers
Hydrologic Engineering Center
609 Second Street
Davis, CA 95616-4687

Public Domain

Yes

Comments

Includes culvert analysis and floodway options.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: HY8 4.1 and up (Nov. 1992)

Developed By

U.S. Department of Transportation,
Federal Highway Administration (FHWA)

Available From

Federal Highway Administration

Public Domain

Yes

Comments

Computes water-surface elevations for flow through multiple parallel culverts and over the road embankment.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: PondPack v. 8 (May 2002) and up

Developed By

Bentley Systems

Available From

Bentley Systems
685 Stockton Drive
Exton, PA 19341

Public Domain

No

Comments

Cannot model ineffective flow areas. HEC-RAS or an equivalent program must be used to model tail water conditions when ineffective flow areas must be considered.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: QUICK-2 1.0 and up (Jan. 1995)

Developed By

FEMA

Available From

Federal Emergency Management Agency
Federal Insurance and Mitigation Administration
500 C Street, SW
Washington, DC 20472

FEMA Flood Hazard Mapping Software

Public Domain

Yes

Comments

Intended for use in areas studied by approximate methods (Zone A) only. May be used to develop water-surface elevations at one cross section or a series of cross sections. May not be used to develop a floodway.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: RASPLOT 3.0 Beta and up

Developed By

FEMA

Available From

Federal Emergency Management Agency
Federal Insurance and Mitigation Administration
500 C Street, SW
Washington, DC 20472

RASPLOT

Public Domain

n/a

Comments

RASPLOT is a computer program developed by the Federal Emergency Management Agency (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.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: StormCAD v.4 (June 2002) and up

Developed By

Bentley Systems

Available From

Bentley Systems
685 Stockton Drive
Exton, PA 19341

Public Domain

No

Comments

Only applicable to watershed, which has the drainage area to each inlet of less than 300 acres.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: WSPGW 12.96 (Oct. 2000) and up

Developed By

Los Angeles Flood Control District and Joseph E. Bonadiman & Associates, Inc.

Available From

Joseph E. Bonadiman & Associates, Inc.
234 N. Arrowhead Avenue,
San Bernardino, CA 92408

Public Domain

No

Comments

Windows version of WSPG. Computes water-surface profiles and pressure gradients for open channels and closed conduits. Can analyze multiple parallel pipes. Road overtopping cannot be computed. Open channels are analyzed using the standard step method but roughness coefficient cannot vary across the channel. Overbank analyses cannot be done. Multiple parallel pipe analysis assumes equal distribution between pipes so pipes must be of similar material, geometry, slope, and inlet configuration. Floodway function is not available.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: WSPRO (Jun. 1988 and up)

Developed By

U.S. Geological Survey (USGS),
Federal Highway Administration (FHWA)

Available From

Federal Highway Administration

Public Domain

Yes

Comments

Floodway option is available in June 1998 version. 1988 version is also available.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: XPSWMM version 8.52 and up XPStorm 10.0 (May 2006) and up

Developed By

Innovyze

Available From

Innovyze
6720 SW Macadam Avenue, Suite 200
Portland, OR 97219

Public Domain

No

Comments

Model must be calibrated to observe flows, or discharge per unit area must be shown to be reasonable in comparison to nearby gage data, regression equations or other accepted standards for 1% annual chance events.

Calibration or verification to the actual flood events highly recommended.

XPStorm has the same stormwater modeling capability as the XPSWMM program.

^ Return to top

One-Dimensional Unsteady Flow Models

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: FEQ 9.98 and FEQUTL 5.46 (2005, both), and up

Developed By

Delbert D. Franz, Linsley, Kraeger Associates;
and Charles S. Melching, USGS

Available From

U.S. Geological Survey
221 North Broadway Avenue
Urbana, IL 61801
USGS.gov/proj/feq/

Public Domain

Yes

Comments

The FEQ model is a computer program for the solution of full, dynamic equations of motion for one-dimensional unsteady flow in open channels and control structures. The hydraulic characteristics for the floodplain (including the channel, overbanks, and all control structures affecting the movement of flow) are computed by its companion program FEQUTL and used by the FEQ program.

Calibration or verification to the actual flood events highly recommended.
Floodway concept formulation is unavailable.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: FLDWAV (Nov. 1998)

Developed By

National Weather Service (NWS)

Available From

Hydrologic Research Laboratory
Office of Hydrology
National Weather Service, NOAA
1345 East-West Highway
Silver Spring, MD 20910

Public Domain

Yes

Comments

Includes all the features of DAMBRK and DWOPER plus additional capabilities. It is a computer program for the solution of the fully dynamic equations of motion for one-dimensional flow in open channels and control structures. Floodway concept formulation is unavailable.

Calibration to actual flood events required.

This model has the capability to model sediment transport. Program is supported by NWS.

National Weather Service FLDWAV Computer Program 

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program:FLO-2D v. 2007.06 and 2009.06

Developed By

Jimmy S. O'Brien

Available From

FLO-2D Software, Inc.
P.O. Box 66
Nutrioso, AZ 85932

Public Domain

No

Comments

Hydrodynamic model for the solution of the fully dynamic equations of motion for one-dimensional flow in open channels and two-dimensional flow in the floodplain. Bridge or culvert computations must be accomplished external to FLO-2D using methodologies or models accepted for NFIP usage.

Please review 'Guidelines and Specifications for Flood Hazard Mapping Partners, Appendix G: Guidance for Alluvial Fan Flooding Analyses and Mapping (Feb 2002)' thoroughly before applying to alluvial fans. Coordination with the Regional office is required. Calibration to actual flood events is required.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: HEC-RAS 3.1.1 and up

Developed By

U.S. Army Corps of Engineers (USACE)

Available From

Water Resources
Support Center
U.S. Army Corps of Engineers
Hydrologic Engineering Center
609 Second Street
Davis, CA 95616-4687

Public Domain

Yes

Comments

Calibration or verification to the actual flood events is highly recommended. Floodway concept formulation unavailable.

Version 3.1 cannot create detailed output for multiple profiles in the report file. CHECK-RAS cannot extract data.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: HEC-RAS 5.0.0 and up (Mar 2016)

Developed By

U.S. Army Corps of Engineers (USACE)

Available From

Water Resources
Support Center
U.S. Army Corps of Engineers
Hydrologic Engineering Center
609 Second Street
Davis, CA 95616-4687

Public Domain

Yes

Comments

The River Analysis System is able to model excess precipitation applied directly to a 2D flow area. Losses and infiltration are not currently able to be computed within RAS, so excess precipitation should be determined using separate approved hydrologic methods or software (such as HEC-HMS) prior to applying it within the model domain.

Calibration runs against available gage or other study data should be used wherever possible to validate model output.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: ICPR 2.20 (Oct. 2000), 3.02 (Nov. 2002), 3.10 (April 2008) with PercPack Option and 4.0 "Pro" (May 2018)

Developed By

Streamline Technologies, Inc.

Available From

Streamline Technologies, Inc.
1900 Town Plaza Ct
Winter Springs, FL 32708
Streamnologies.com

Public Domain

No

Comments

The model must be calibrated to observed flow and stage records or high-water marks of actual flood events at both channel and floodplain. Floodway concept formulation unavailable; however, version 3 allows users to specify encroachment stations to cut off the cross section.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: MIKE 11 HD v.2009 SP4

Developed By

DHI Water & Environment

Available From

DHI, Inc.
319 SW Washington St.
Suite 614
Portland, OR 97204

Public Domain

No

Comments

A dynamic coupling of MIKE 11/ MIKE HYDRO River (one-dimensional) and MIKE 21 (two-dimensional) models. Solves the fully dynamic equations of motion for one- and two-dimensional flow in open channels, riverine flood plains, alluvial fans and in costal zones. This allows for embedding of sub-grid features as 1-D links within a 2-D modeling domain. Examples of sub-grid features could include small channels, culverts, weirs, gates, bridges and other control structures.

Please review 'Guidelines and Specifications for Flood Hazard Mapping Partners Appendix C: Guidance for Riverine Flooding Analyses and Mapping (Feb 2002)' thoroughly before applying to floodway analysis. Coordination with the Regional office is required.

The model must be calibrated to observed flow and stage records or high-water marks of actual flood events at both channel and floodplain.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: MIKE 11 (2009 SP4)<br>MIKE 11 HD v.2009 SP4

Developed By

DHI Water & Environment

Available From

DHI, Inc.
319 SWM Washington St, Suite 614
Portland, OR 97204

Public Domain

No

Comments

Hydrodynamic model for the solution of the fully dynamic equations of motion for one-dimensional flow in open channels and control structures. The floodplain can be modeled separately from the main channel.

Calibration to actual flood events is required. Floodway concept formulation is available for steady flow conditions. This model has the capability to model sediment transport.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: MIKE 11 v.2009 SP4 and up <br>MIKE HYDRO River v.2016 and up

Developed By

DHI Water & Environment

Available From

DHI Water & Environment Inc.
141 Union Blvd., Ste 250
Lakewood, Colorado, 80228, USA

Public Domain

No

Comments

MIKE HYDRO River is DHI’s new river modeling software package. It utilizes MIKE 1D as its computational engine. The MIKE 1D engine is the result of a re-engineering merger process of the calculation capabilities of DHI’s collection system (MOUSE) and river simulation engine (MIKE 11) into one engine.

Calibration or verification to the actual flood events highly recommended.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: SWMM 5 Version 5.0.005 (May 2005) and up

Developed By

U.S. Environmental Protection Agency (EPA)

Available From

Water Supply and Water Resources Division

U.S. Environmental Protection Agency

Public Domain

Yes

Comments

SWMM 5 provides an integrated environment for editing study area input data, running hydrologic simulations, and viewing the results in a variety of formats.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: UNET 4.0 (April 2001)

Developed By

U.S. Army Corps of Engineers (USACE)

Available From

Water Resources
Support Center
U.S. Army Corps of Engineers
Hydrologic Engineering Center
609 Second Street
Davis, CA 95616-4687

Public Domain

Yes

Comments

The model must be calibrated to observed flow and stage records or high-water marks of actual flood events at both channel and floodplain. Comparison of bridge and culvert modeling to other numerical models reveals significant differences in results; these differences may be investigated in the near future. Floodway option is not accepted for NFIP usage.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: XPSWMM version 8.52 and up XPStorm 10.0 (May 2006) and up

Developed By

Innovyze

Available From

Innovyze
6720 SW Macadam Avenue Suite 200
Portland, OR 97219

Public Domain

No

Comments

Model must be calibrated to observe flows, or discharge per unit area must be shown to be reasonable in comparison to nearby gage data, regression equations or other accepted standards for 1% annual chance events.

Calibration or verification to the actual flood events highly recommended.

XPStorm has the same stormwater modeling capability as the XPSWMM program.

Two-Dimensional Steady/Unsteady Flow Models

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: Adaptive Hydraulics (AdH) version 4.2 and up (June 2012)

Developed By

U.S. Army Corps of Engineers (USACE)

Available From

U.S. Army Engineer Research and Development Center Coastal and Hydraulics Laboratory

3909 Halls Ferry Rd., Vicksburg, MS 39180

Public Domain

Yes

Comments

AdH is a spatially implicit, physics based hydrodynamic model that can simulate a wide range of hydraulic features, including rainfall and evaporation, overland flooding, wind and wave effects, friction impacts due to vegetation, and several types of hydraulic structures. AdH also includes the ability to simulate time and space varying head and flow boundary conditions, making it suitable in many coastal, estuarine, and riverine applications. AdH has been applied in the high tidal ranges of Alaska and in the deserts of Afghanistan. AdH has been used widely throughout the U.S. for sediment and constituent transport, dam break, tidal impacts, and flooding analyses. User manual and various training resources for the AdH model is available on the AdH website. More information on AdH can be found on the USACE website.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: FESWMS 2DH 1.1 and up (Jun. 1995)

Developed By

U.S. Geological Survey

Available From

U.S. Geological Survey
National Center
12201 Sunrise Valley Drive
Reston, VA 22092

Public Domain

Yes

Comments

 This model has the capability to model sediment transport. Please review the applicable guidance for FEMA’s Risk Mapping, Assessment, and Planning thoroughly before applying to floodway analysis. Coordination with the Regional office is required.

Please review 'Guidelines and Specifications for Flood Hazard Mapping Partners, Appendix G: Guidance for Alluvial Fan Flooding Analyses and Mapping (Feb 2002)' thoroughly before applying to alluvial fans. Coordination with the Regional office is required.

The model must be calibrated to observed flow and stage records or high-water marks of actual flood events at both channel and floodplain.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: FLO-2D v. 2007.06 and 2009.06

Developed By

Jimmy S. O'Brien

Available From

FLO-2D Software, Inc.
P.O. Box 66
Nutrioso, AZ 85932 FLO-2d.com/

Public Domain

No

Comments

Hydrodynamic model that has the capabilities of modeling unconfined flows, complex channels, sediment transport, and mud and debris flows. Please review the applicable guidance for FEMA’s Risk Mapping, Assessment, and Planning thoroughly before applying to floodway analysis. Coordination with the Regional office is required.

Please review 'Guidelines and Specifications for Flood Hazard Mapping Partners, Appendix G: Guidance for Alluvial Fan Flooding Analyses and Mapping (Feb 2002)' thoroughly before applying to alluvial fans. Coordination with the Regional office is required.

The model must be calibrated to observed flow and stage records or high-water marks of actual flood events at both channel and floodplain.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: HEC-RAS Version 5.0 and up (Mar 2016)

Developed By

U.S. Army Corps of Engineers (USACE)

Available From

Water Resources
Support Center
U.S. Army Corps of Engineers
Hydrologic Engineering Center
609 Second Street
Davis, CA 95616-4687

Public Domain

Yes

Comments

The River Analysis System is able to model excess precipitation applied directly to a 2D flow area. Losses and infiltration are not currently able to be computed within RAS, so excess precipitation should be determined using separate approved hydrologic methods or software (such as HEC-HMS) prior to applying it within the model domain.

Calibration runs against gage or other study data should be used wherever possible to validate model output.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: MIKE FLOOD HD v.2009 SP4

Developed By

DHI Water & Environment

Available From

DHI, Inc.
319 SWM Washington St, Suite 614
Portland, OR 97204

Public Domain

No

Comments

A dynamic coupling of MIKE 11/ MIKE HYDRO River (one-dimensional) and MIKE 21 (two-dimensional) models. Solves the fully dynamic equations of motion for one- and two-dimensional flow in open channels, riverine flood plains, alluvial fans and in costal zones. This allows for embedding of sub-grid features as 1-D links within a 2-D modeling domain. Examples of sub-grid features could include small channels, culverts, weirs, gates, bridges and other control structures.

Please review 'Guidelines and Specifications for Flood Hazard Mapping Partners, Appendix G: Guidance for Alluvial Fan Flooding Analyses and Mapping (Feb 2002)' thoroughly before applying to alluvial fans. Coordination with the Regional office is required.

The model must be calibrated to observed flow and stage records or high-water marks of actual flood events at both channel and floodplain.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: MIKE FLOOD HD v.2009 SP4 and up.

Developed By

DHI Water & Environment

Available From

DHI Water & Environment Inc.
141 Union Blvd., Ste 250
Lakewood, Colorado, 80228, USA

Public Domain

No

Comments

A dynamic coupling of MIKE 11/ MIKE HYDRO River (one-dimensional) and MIKE 21 (two-dimensional) models. Solves the fully dynamic equations of motion for one- and two-dimensional flow in open channels, riverine flood plains, alluvial fans and in coastal zones. This allows for embedding of sub-grid features as 1-D links within a 2-D modeling domain. Examples of sub-grid features could include small channels, culverts, weirs, gates, bridges and other control structures.

Please review 'Guidelines and Specifications for Flood Hazard Mapping Partners Appendix C: Guidance for Riverine Flooding Analyses and Mapping (Feb 2002)' thoroughly before applying to floodway analysis. Coordination with the Regional office is required.

The model must be calibrated to observed flow and stage records or high-water marks of actual flood events at both channel and floodplain.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: Sedimentation and River Hydraulics, Two-Dimensional River Flow Model (SRH-2D)

Developed By

U.S. Bureau of Reclamation
Technical Service Center
Sedimentation and River Hydraulics Group
Denver Federal Center
6th and Kipling, Building 67
Denver, Colorado 80225-0007

Available From

U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590

Public Domain

Yes

Comments

SRH-2D, Sedimentation and River Hydraulics – Two-Dimensional model, is a two-dimensional (2D) hydraulic, sediment, temperature, and vegetation model for river systems. The SRH-2D model can be executed independently of any third party software, but pre-processing greatly facilitates development of the computational mesh elements. Public domain alternatives are available for this pre-processing. However, FHWA has contracted with the firm AquaVeo to integrate the SRH-2D model into their Surface-water Modeling System (SMS).

SRH-2D may be applied but not limited to: Flow in one or multiple streams covering the main channel, side channels, and floodplains; Hybrid mesh methodology which uses arbitrary mesh cell shapes; Flood routing and inundation mapping over any terrain; Flow around in-stream structures such as weirs, diversion dams, release gates, coffer dams, etc.; Flow over-spill over banks and levees; Flow over vegetated areas and interaction with main channel flows; Flow in reservoirs with known flow release; and Morphological assessment of bed erosion potential.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: TABS RMA2 v. 4.3 and up (Oct 1996) RMA4 v. 4.5 and up (July 2000)

Developed By

US Army Corps of Engineers (USACE)

Available From

Coastal Engineering Research Center
Department of the Army Waterways Experiment Station
Corps of Engineers
3909 Halls Ferry Road
Vicksburg, MS 39180-6199

Public Domain

Yes

Comments

Limitations on split flows. Floodway concept formulation unavailable. More review anticipated for treatment of structures.

Please review 'Guidelines and Specifications for Flood Hazard Mapping Partners Appendix C: Guidance for Riverine Flooding Analyses and Mapping (Feb 2002)' thoroughly before applying to floodway analysis. Coordination with the Regional office is required.

Please review 'Guidelines and Specifications for Flood Hazard Mapping Partners.Appendix G: Guidance for Alluvial Fan Flooding Analyses and Mapping (Feb 2002)’ thoroughly before applying to alluvial fans. Coordination with the Regional office is required.

The model must be calibrated to observed flow and stage records or highwater marks of actual flood events at both channel and floodplain.

Graphic
Icon of a Graphic Document Showing a Triangle with Crop Marks

Program: XPSWMM, XPStorm 10.0 and up

Developed By

Innovyze

Available From

Innovyze
6720 SW Macadam Avenue Suite 200
Portland, OR 97219

Public Domain

No

Comments

The program simulates two-dimensional free surface flows by solving the full-dimensional, depth averaged, momentum and continuity equations. The two-dimensional simulation is dynamically linked with the one-dimensional modeling of XPSWMM/XPStorm by taking the one-dimensional water surface elevation profile as the internal boundray condition of the 2D domain. Flow rates transferred depend upon the head difference and the roughness of cells.

The program does not have any option to model weir flow along 1D/2D boundary; caution must be applied when transfer of flow along these boundaries.

The model must be calibrated to observed flow and stage records or high-water marks of actual flood events on both channel and floodplain.

^ Return to top

Locally Accepted Hydraulic Models

Hydraulic Models: Determination of Water-surface Elevations for Riverine Analysis

More Nationally and Locally Accepted Models

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.

^ Return to top