VFSMOD: Vegetative Filter Strip Modeling System
Software Updates
VFSMOD-W windows version - deprecated
The Windows GUI is no longer maintained at this time due to lack of resources. The last version of the GUI can be downloaded from please visit the Download & Registration section for full installation. After downlaod and installation, the latest versions of command line VFSM.EXE and UH.EXE programs can be downloaded below and replaced on the c:/VFSMOD-W folder. However, some features of the recent comand line programs are not supported by the obsolete GUI.
Latest VFSMOD Command line program (vfsm.exe v4.5.2)
Maintainance update for v4.5.1: February 20, 2023
Changes:
- v4.5.2 minor update over v4.5.1. Added new option (N= -1) in .IWK file so that the number of nodes (N) is calculated internally based on the filter size VL. If the user selects an N it will be used intead (backwards compatible).
- Error in d50 dynamic calculation (NPART=8) fixed in v4.5.1. Before it used peak rainfall intensity (.irn) instead of the required mean rainfall intensity for the storm (calculated from .irn)
- New processes that add realism to the simulations are included in VFSMOD version 4.5. a) avoids the arbitrary parametrization of the incoming sediment characteristics in favor of a dynamic calculation of these based on each event characteristics; b) the pesticide mass in the mixing layer is calculated based on non-uniform leaching with soil depth during infiltration based on the physical CDE (convective-dispersive-dispersive equation) transport; and c) provides robust mechanistic runoff remobilization of residues across all products (from low to very high sorption and from labile to persistent). Only one new input is needed in the program input file .IWQ, DGMRES0 the last event surface residue pesticide mass dissolved in porewater remobilized in the next runoff event, that is provided in the .OWQ output file from previous event simulated in the series. The .OWQ output file now has been extended with more information on the new processes, but for backwards compatibility the content on the first part of the output file has not changed. For additional details, please see CHANGES.txt file inside src_vfsm directory within the ZIP package below.
- Download VFSM.EXE (v4.5.2) [17.6 MB]. Windows command line executable, working directories, samples and fortran source code files (includes unix makefile). To update the Windows (64-bit) version, replace vfsm.exe in the c:\vfsmod-w\ by the one included in this package. a Windows 32-bit executable (VFSM32.EXE) is also included for older machines along with the default 64-bit version.
Updated UH Command line program (uh.exe v3.0.7)
Release date: Feb, 2023
Changes: see list of changes
- Download UH.EXE (v3.0.7) included in the latest updated VFSMOD distribution folder described above. It includes Windows 64-bit command line executable, and sample ".INP" files (including examples for user supplied cumulative hyetographs different than standard USDA NRCS types I, IA, II and III - option "storm type"=5 in .INP file).
Archived (older) versions
VFSMOD Command line program (vfsm.exe v4.4.3)
Release date: August, 2020
Changes: a) Updated code to handle the updated soil (.ISO) file for the shallow water table (WT) case (see manual for details). Two changes were made to minimize and simplify the input requirements for WT conditions: a1) the end bottom boundary condition (for t>tw) is now hard-set to the Dupuis-Forchheimer (DF) lateral draining stream (the code still contains the Vachaud vertical draining condition that is commented-out); a2) the last line in the .iso file (if present) reads the heterogeneity ratio between horizontal and vertical conductivities for the lateral DF end bottom boundary condition, and if not given is assumed to 1 (homogenous); and c) the bubbling pressure is now only a parameter of Brooks-Corey soil characteristic curves, where the van Genuchten curves are applied to the full range from saturation. b) Updated model PDF documentation (online and in distribution package) to include shallow water table (description and command line and windows users), new pesticide equations and brief description of use for regulatory pesticide exposure assessments; new references. For additional details, please see CHANGES.txt file inside src_vfsm directory within the ZIP package below.
- Download VFSM.EXE (v4.4.3) [13.5 MB]. Windows command line executable, working directories, samples and fortran source code files (includes unix makefile).To update the Windows (64 bit) version, replace vfsm.exe in the c:\vfsmod-w\ by the one included in this package.
VFSMOD Command line program (vfsm.exe v4.4.0)
Release date: August, 2018
Changes: please see CHANGES.txt file inside src_vfsm directory within the ZIP package below.
- Download VFSM.EXE (v4.4.3) [13.5 MB].Download Windows command line executable, working directories, samples and fortran source code files (includes unix makefile).To update the Windows version, rename vfsm32.exe included in this package to vfsm.exe, and substitute this in the original c:\vfsmod-w\ directory.
UH Command line program (uh.exe v3.0.2)
Release date: February, 2014
Changes: a) Added user table for 24-h hyetograph (v3.0.1); b) Fixed user hyetograph option (jstype=5) (v3.0.2).
- Download UH.EXE (v3.0.2) Windows command line executable, and sample ".INP" file with the "storm type - User selected" option. Notice that in this case Storm type in the INP files is set to "5" and the user must provide at the end of the file "tmid(hr)", the time to the middle time in the storm (where P/P24=0.5), followed the normalized (P/P24) 24-hr cumulative precipitation curve. See example in the ZIP download. Notice that although the curve must be provided for 24 hrs., the program automatically scales the curve to the user selected duration (D).
VFSMOD-W v5.1.8 (archive)
Release date: October 31, 2009
Bug: When selecting the water quality option on the project interface, the user cannot change the name of the IWQ and OWQ files manually. Problem with international users in the soil parameters window when using commas as decimal separator in numbers.
Fix: Users can now edit manually the names of the IWQ and OWQ files from project interface. Input check added to soil parameters window. However, this has not been propagated through the rest of the GUI program yet. User is advised to change international preferences in Windows to US so points are used to separate decimals in numbers. See Windows help for this issue.
New Features: none
To Install: Download the ZIP file that contains the new GUI executable (vfsmod-w.exe) from the link above and substitute the old file in the "vfsmod-w" installation directory. When you start the program up again it should display version 5.1.8 in the splash window.
VFSMOD-W v5.1.7 (archive)
Release date: April 23, 2009
Bug: When the new design graphical outputs window was maximized, when selecting one of the other outputs (RDR, SDR or PDR), the program would quit unexpectedly. In addition, none of the VFSMOD-W graph windows would resize properly when maximized (i.e., the window became larger but the graph would retain the original size).
Fix: All the program's graphical output windows now resize properly and the program no longer quits when selecting a different design output graph when maximized.
New Features: A new execution status bar has been added to the design runs information window.
To Install: Download the ZIP file that contains the new GUI executable (vfsmod-w.exe) from the link above and substitute the old file in the "vfsmod-w" installation directory. When you start the program up again it should display version 5.1.7 in the splash window.
VFSMOD-W v5.1.6 (archive)
Release date: March 6, 2009
Bug: The water quality file edit screen did not save the values when the "direct input" (Kd value) was selected. Also the new pesticide routine in the fortran vfsm.exe program (vfsm.exe) was missing a statements to check for cases where 100% pesticide reduction was obtained when no flow went through the filter.
Fix: Revised GUI procedure now allows for saving values into IWQ file. New vfsm.exe included with pesticide subroutine check added.
New Features: Graphical output for design result is now added along with documentation of the new feature added to the revised program help file. Minor cosmetic changes added (v5.1.6).
To Install: Download the ZIP file that contains the new GUI executable (vfsmod-w.exe), command line program (vfsm.exe) and revised help file (vfsmod-w.HLP) from the link above and substitute the old files in the "vfsmod-w" installation directory by these. When you start the program up again it should display version 5.1.6 in the splash window.
This page was last updated on March 31, 2023.