Numerical Models Meeting the Minimum Requirement of NFIP

Nationally Accepted Hydraulic Models as of March 2008

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.

Hydraulic Models: Determination of Water-Surface Elevations for Riverine Analysis
PROGRAM DEVELOPED BY AVAILABLE FROM COMMENTS
One-Dimensional Steady Flow Models
HEC-RAS 3.1.1 and up U.S. Army Corps of Engineers Water Resources Support Center
Corps of Engineers
Hydrologic Engineering Center
609 Second Street
Davis, CA 95616-4687

www.hec.usace.army.mil/
For water surface elevation difference due to use of different HEC-RAS versions, refer to FEMA Memorandum HEC-RAS Version Updates (August 17, 2004)

www.fema.gov/library/viewRecord.do?id=2295

Public Domain: Yes
HEC-2 4.6.2 1
(May 1991)
US Army Corps of Engineers Water Resources Support Center 2
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:

www.fhwa.dot.gov/
engineering/hydraulics/
software/softwaredetail.cfm
Floodway option is available in June 1998 version. 1988 version is available on the USGS web page at:

water.usgs.gov/software/
surface_water.html

Public Domain: Yes
QUICK-2 1.0 and up
(Jan. 1995)
FEMA Federal Emergency Management Agency
Mitigation Directorate
500 C Street, SW
Washington, DC 20472

www.fema.gov/plan/prevent/
fhm/frm_soft.shtm
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:

www.fhwa.dot.gov/
engineering/hydraulics/
software/softwaredetail.cfm
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 6 th Street
San Bernardino, CA 92410

www.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. Demo version available from:

www.bonadiman.com/
software/wspg.htm


Public Domain: No
StormCAD v.4 (June 2002) and up Bentley Systems Bentley Systems
685 Stockton Drive
Exton, PA  19341

www.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

www.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

www.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 Software XP-Software,
2000 NE 42 nd Ave. #214
Portland , OR 97213-1305

www.xpsoftware.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

www.fema.gov/library/viewRecord.do?id=2348

Public Domain: No
Xpstorm 10.0 (May 2006) XP Software XP-Software,
2000 NE 42 nd Ave. #214
Portland , OR 97213-1305

www.xpsoftware.com
Xpstorm has the same stormwater modeling capability as the XP-SWMM program.
One-Dimensional Unsteady Flow Models
HEC-RAS 3.1.1 and up US Army Corps of Engineers Water Resources Support Center
Corps of Engineers
Hydrologic Engineering Center (HEC)
609 Second Street
Davis, CA 95616-4687

www.hec.usace.army.mil/
Calibration or verification to the actual flood events 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),FEQ 8.92 and
FEQUTL 4.68
(1999, both)
Delbert D. Franz, Linsley, Kraeger
Associates; and Charles S. Melching,
USGS
U.S. Geological Survey
221 North Broadway Avenue
Urbana, IL 61801

il.water.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) and 3.02 (Nov. 2002) Streamline Technologies, Inc. Streamline Technologies, Inc.
6961 University Boulevard
Winter Park, FL 32792

www.streamnologies.com
Calibration or verification to the actual flood events highly recommended. Floodway concept formulation unavailable; however, version 3 allows user 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 Water Supply and Water Resources Division
U.S. Environmental Protection Agency

www.epa.gov/ednnrmrl/
models/swmm/index.htm
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 Water Resources Support Center
Corps of Engineers
Hydrologic Engineering Center (HEC)
609 Second Street
Davis, CA 95616-4687
Calibration or verification to the actual flood events highly recommended. 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 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.

Public Domain: Yes
MIKE 11 HD
(2002 D, 2004)
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 highly recommended. Floodway concept formulation is available for steady flow conditions. This model has the capability to model sediment transport. The web page is at:

www.dhisoftware.com/mike11/

Public Domain: No
FLO-2D v. 2006.01 and 2007.06 Jimmy S. O'Brien FLO-2D Software, Inc.
P.O. Box 66
Nutrioso, AZ 85932

www.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. Calibration to actual flood events required. Floodway option is under review. User of Version 2006.01 is strongly encouraged to update to the latest version for bug correction.

Public Domain: No
XP-SWMM 8.52 and up XP Software XP-Software,
2000 NE 42nd Ave. #214
Portland, OR 97213-1305

www.xpsoftware.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

www.fema.gov/library/viewRecord.do?id=2348

Public Domain: No

Xpstorm 10.0 (May 2006) XP Software XP-Software,
2000 NE 42 nd Ave. #214
Portland , OR 97213-1305

www.xpsoftware.com
Xpstorm has the same stormwater modeling capability as the XP-SWMM program.
Two-Dimensional Steady/Unsteady Flow Models
TABS
­RMA2 v. 4.3
(Oct. 1996)
­RMA4 v. 4.5
(July 2000)
US Army Corps of Engineers 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.

Public Domain: Yes
FESWMS 2DH
1.1 and up
(Jun. 1995)
US Geological Survey U.S. Geological Survey
National Center
12201 Sunrise Valley Drive
Reston, VA 22092

water.usgs.gov/software/
surface_water.html
Region 10 has conducted study in Oregon. Floodway concept formulation unavailable. This model has the capability to model sediment transport.

Public Domain: Yes
FLO-2D v. 2006.01 and 2007.06 Jimmy S. O'Brien FLO-2D Software, Inc.
Tetra Tech, ISG
P.O. Box 66
Nutrioso, AZ 85932

www.flo-2d.com/
Hydrodynamic model that has the capabilities of modeling unconfined flows, complex channels, sediment transport, and mud and debris flows. It can be used for alluvial fan modeling. Floodway option is under review. User of Version 2006.01 is strongly encouraged to update to the latest version for bug correction.

Public Domain: No
MIKE Flood HD 2002 D, 2004 and 2005 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. Calibration for actual flood events is highly recommended. The web page is at

www.dhisoftware.com/mikeflood/

Public Domain: No

1 The enhancement of these programs in editing and graphical presentation can be obtained from several private companies.
2 Program is typically distributed by vendors and may not be available through HEC. A list of vendors may be obtained through HEC.

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Last Modified: Thursday, 21-Aug-2008 11:54:22 EDT