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

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This page provides a list of nationally and locally accepted hydraulic 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, where the compliance with the requirements of 44 CFR 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, so be sure to read and apply them each time you reference the chart below.

One-Dimensional Steady Flow Models

Program

Developed By

Available From

Comments

cHECk-RAS

Federal Emergency Management Agency (FEMA)

Federal Emergency Management Agency
Federal Insurance and Mitigation Administration 
500 C Street, SW
Washington, DC 20472 and the cHECk-RAS webpage:

http://www.fema.gov/check-ras

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.

HEC-RAS 3.1.1 and up

U.S. Army Corps of Engineers (USACE)

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

http://www.hec.usace.army.mil/software/hec-ras/

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

HEC-RAS Program Update 

Public Domain: Yes

HEC-2 4.6.2 1
(May 1991)

US Army Corps of Engineers (USACE)

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

Includes culvert analysis and floodway options.

Public Domain: Yes

WSPRO
(Jun. 1988 and up)

US Geological Survey,
Federal Highway Administration (FHWA)

Federal Highway Administration (FHWA) web page at:

FHWA.dot

Floodway option is available in June 1998 version. 1988 version is available on the USGS web page at:

Water.USGS.gov

Public Domain: Yes

QUICK-2 1.0 and up
(Jan. 1995)

FEMA

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

FEMA.gov/plan

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.

Public Domain: Yes

HY8 4.1 and up
(Nov. 1992)

US Department of Transportation, Federal Highway Administration (FHWA)

Federal Highway Administration (FHWA) web page at:

FHWA.dot.gov

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

Public Domain: Yes

WSPGW 12.96
(Oct. 2000) and up

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

Joseph E. Bonadiman & Associates, Inc.
588 West 6th Street
San Bernardino, CA 92410

Bonadiman.com

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.

Public Domain: No

RASPLOT 3.0 Beta

FEMA

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

www.fema.gov/rasplot

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.

StormCAD v.4 (June 2002) and up

Bentley Systems

Bentley Systems
685 Stockton Drive
Exton, PA 19341

Bentley.com/en-US

Perform backwater calculations. Should not be used for systems with more than two steep pipes (e.g. supercritical conditions). Inflow is computed by using the Rational Method; the program is only applicable to watershed, which has the drainage area to each inlet less than 300 acres.

Public Domain: No

PondPack v. 8
(May 2002) and up

Bentley Systems

Bentley Systems
685 Stockton Drive
Exton, PA 19341

Bentley.com/en-US

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.

Public Domain: No

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

Bentley Systems

Bentley Systems
685 Stockton Drive
Exton, PA 19341

Bentley.com/en-US

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

Public Domain: No

XP-SWMM 8.52 and up

XP Solutions

XP Solutions
5415 SW Westgate Dr.
Suite 150
Portland, OR 97221

XPSolutions.com

XP-SWMM cannot represent more than three Manning’s n values per channel section. Where more than this number of values per section are required, the user must demonstrate that the three n values used accurately depict the composite n value for the entire section at various depths. The floodway procedures are for steady flow purposes only. Refer to procedures for unsteady flow floodway calculation posted on the FEMA website at

Floodway Analysis for SWMM Models 

Public Domain: No

Xpstorm 10.0
(May 2006)

XP Solutions

XP Solutions
5415 SW Westgate Dr.
Suite 150
Portland, OR 97221

XPSolutions.com

Xpstorm has the same stormwater modeling capability as the XP-SWMM program.

Public Domain: No

One-Dimensional Unsteady Flow Models

Program

Developed By

Available From

Comments

HEC-RAS 3.1.1
and up

US Army Corps of Engineers (USACE)

Water Resources
Support Center
Corps of Engineers
Hydrologic Engineering Center (HEC)
609 Second Street
Davis, CA 95616-4687

HEC.usace.army.mil/

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.

Public Domain: Yes

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

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

U.S. Geological Survey
221 North Broadway Avenue
Urbana, IL 61801

USGS.gov/proj/feq/

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.

Public Domain: Yes

ICPR 2.20 (Oct. 2000), 3.02 (Nov. 2002), and 3.10 (April 2008) with PercPack Option

Streamline Technologies, Inc.

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

Streamnologies.com

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.

Public Domain: No

SWMM 5 Version 5.0.005 (May 2005) and up

U.S. Environmental Protection Agency (EPA)

Water Supply and Water Resources Division

U.S. Environmental Protection Agency

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

Public Domain: Yes

UNET 4.0
(April 2001)

U.S. Army Corps of Engineers (USACE)

Water Resources
Support Center
Corps of Engineers
Hydrologic Engineering Center (HEC)
609 Second Street
Davis, CA 95616-4687

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.

Public Domain: Yes

FLDWAV
(Nov. 1998)

National Weather Service (NWS)

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

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 

Public Domain: Yes

MIKE 11 HD v.2009 SP4

DHI Water and Environment

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

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. The web page is at:

DHisoftware.com/ 

Public Domain: No

FLO-2D v. 2007.06 and 2009.06

Jimmy S. O'Brien

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

FLO-2d.com/

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.

Public Domain: No

XP-SWMM 8.52 and up

XP Solutions

XP Solutions
5415 SW Westgate Dr.
Suite 150
Portland, OR 97221

XPSolutions.com

XP-SWMM cannot represent more than three Manning’s n values per channel section. Where more than this number of values per section are required, the user must demonstrate that the three n values used accurately depict the composite n value for the entire section at various depths.

Calibration to actual flood events required. The floodway procedures are for steady flow purposes only. Use the procedure for unsteady flow floodway calculation posted on FEMA website at

Floodway Analysis for SWMM Models

Public Domain: No

Xpstorm 10.0 (May 2006)

XP Solutions

XP Solutions
5415 SW Westgate Dr.
Suite 150
Portland, OR 97221

XPSolutions.com

Xpstorm has the same stormwater modeling capability as the XP-SWMM program.

Public Domain: No

Two-Dimensional Steady/Unsteady Flow Models

Program

Developed By

Available From

Comments

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

U.S. Army Corps of Engineers (USACE)

U.S. Army Engineer Research and Development Center Coastal and Hydraulics Laboratory, 3909 Halls Ferry Rd., Vicksburg, MS 39180

http://adh.usace.army.mil/new_webpage/main/main_page.htm

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 at:

http://chl.erdc.usace.army.mil/adh

Publically Available: Yes

FESWMS 2DH
1.1 and up
(Jun. 1995)

U.S. Geological Survey

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

USGS.gov/

This model has the capability to model sediment transport.

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 high-water marks of actual flood events at both channel and floodplain.

Public Domain: Yes

FLO-2D v. 2007.06 and 2009.06

Jimmy S. O'Brien

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

FLO-2d.com/

Hydrodynamic model that has the capabilities of modeling unconfined flows, complex channels, sediment transport, and mud and debris flows.


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 high-water marks of actual flood events at both channel and floodplain.

Public Domain: No

MIKE Flood HD v.2009 SP4

DHI Water and Environment

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

A dynamic coupling of MIKE 11 (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.

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.

DHisoftware.com/ 

Public Domain: No

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

US Army Corps of Engineers (USACE)

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

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 high-water marks of actual flood events at both channel and floodplain.

Public Domain: Yes

XPSWMM 2D/
XPStorm 2D
v. 12.00
(May 2010)

XP Solutions

XP Solutions
5415 SW Westgate Dr.
Suite 150
Portland, OR 97221

XPSolutions.com

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 XP-SWMM/XP-Storm by taking the one-dimensional water surface elevation profile as the internal boundary 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.
 

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 high-water marks of actual flood events on both channel and floodplain.

Public Domain: No

1 The enhancement of the program in editing and graphical presentation can be obtained from several private companies.

Current Locally Accepted Hydraulic Models

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

PROGRAMDEVELOPED BYAVAILABLE FROMCOMMENTS
One-Dimensional Unsteady Flow Models
NETWORK
(Jun. 2002)
Southwest Florida Water Management DistrictEngineering Section
Resource Management Department
2329 Broad Street
Brooksville, Florida
34604-6899
Interconnected ponds and channels routing model.

Only accepted for usage within Southwest Florida Water Management District. 

Public Domain: Yes
CHAN for Windows v.2.03
(1997)
Aquarian Software, Inc.Aquarian Software 
1415 Briercliff Drive
Orlando, Florida
34604-6899
Calibration or verification to the actual flood events is highly recommended.

Floodway concept formulation is unavailable. Encroachment stations can be specified in editor to cut off section.

Only accepted for usage within Southwest Florida Water Management District. 

Public Domain: No
MIKE URBAN
Collection Systems
(MOUSE)
Release 2009,
dated June 2010
DHI Water and EnvironmentDHI, Inc., 
319 SW Washington St.,
Suite 614,
Portland, OR 97204
MIKE URBAN has the capability to analyze storm sewer networks. Flow conditions associated with weirs, orifices, manholes, detention basins, pumps, and flow regulators can be reflected. Weirs located within the closed conduit have to be modeled as orifices. MOUSE does not independently have the capability to model overland flows; overland flow can be analyzed by coupling MIKE 11 and/ or MIKE 21. Floodway modeling capability is not available. The compliance of the hydrology module of MOUSE is not determined. Calibration to actual flood events is required.

Only Accepted for usage within areas administered by FEMA Region III (DC, DE, MD, PA, VA and WV)

Public Domain: No
Two-Dimensional Unsteady Flow Models
S2DMM
(Feb. 2008)
Tomasello Consulting Engineers, Inc.Tomasello Consulting Engineers, Inc.
5906 Center Street
Jupiter, FL 33458
Applicable to a network of rectangular grids. Capable of routings on natural overland sheetflow areas and water management systems with cascading lakes and channels. Computing runoff from either daily or hourly rainfall with design distributions, using SCS formula with soil storage and soil moisture updated on daily basis. Stage/storage, sheetflow cross sections, and soil types are represented in each computational grid entered via GIS. HEC-2 type cross sections can be entered on specific channel grids and minor channels can be embedded on general grids. Evapotranspiration computations are based on seasonal factors and soil moisture of unsaturated and saturated zones. Interactions with the subsurface conditions are handled by MODFLOW routines. Capable of simulating continuous hydrologic conditions. Cannot compute regulatory floodway.

Please review Appendix C of the Guidelines and Specifications for Flood Hazard Mapping Partners, Guidelines for Riverine Flooding Analyses and Mapping” 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.

Only accepted for usage in the South Florida Water Management District.

Public Domain: No
TUFLOW
Release Version
2010-10
(October 2010)
BMT WBMBMT WBM
www.bmtwbm.com 
Suite 120
8200 S. Akron Street
Centennial
Denver, CO 80112
United States

Software info:
www.tuflow.com 

Aquaveo
www.aquaveo.com 
3210 N. Canyon Road
Suite 300
Provo, Utah 84604
United States
TUFLOW is flood simulation software that simulates the hydrodynamics of water flow using the complete 2D and 1D free-surface flow equations. It includes a wide range of options for modeling structures and urban pipe networks, and for dynamic linking of 2D and 1D solutions.

The program is applicable to riverine flooding, dambreak inundation, urban overland and pipe network flows, and coastal inundation from surges and tsunamis.

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

Currently floodway concept formulation is not available.

Please review Appendix C of the Guidelines and Specifications for Flood Hazard Mapping Partners, “Guidelines for Riverine Flooding Analyses and Mapping” thoroughly before applying to floodway analysis. Coordination with the Regional office is required.

Only accepted for usage in FEMA Region III. 

Public Domain: No
Two-Dimensional Steady/Unsteady Flow Models
DHM 21 and 34
(Aug. 1987)
Theodore V. Hromadka II and
Chung-Cheng Yen
Hromadka & Associate 
Costa Mesa, California

Diffusion flow model that can route unconfined surface and open channel flows. Can be used to model alluvial flooding. Rainfall-runoff output can be used for hydrologic studies. Kinematic routing optional. Floodway concept formulation unavailable. Calibration to actual flood events is recommended.

Please review Appendix C of the Guidelines and Specifications for Flood Hazard Mapping Partners, “Guidelines for Riverine Flooding Analyses and Mapping” thoroughly before applying to floodway analysis. Coordination with the Regional office is required.

Please review Appendix G of the Guidelines and Specifications for Flood Hazard Mapping Partners, “Guidance for Alluvial Fan Flooding Analyses and Mapping” 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.

Only accepted for usage within the San Bernardino County Flood Control District, California.

Public Domain: No

 

View More Nationally and Locally Accepted Models

Below are additional nationally and locally accepted models in the NFIP Program:

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: 
04/02/2015 - 12:45
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