BOSS International

Visual MODFLOW Pro Overview

The industry standard for 3D groundwater flow and contaminant transport modeling. Includes the latest versions of MODFLOW, MODPATH, MT3DMS, RT3D, WinPEST, VMOD 3D-Explorer, Enviro-Base Pro and much more!

Visual MODFLOW Pro Features

Visual MODFLOW Pro is the industry-standard for applications in 3D groundwater flow and contaminant transport modeling. Visual MODFLOW Pro seamlessly integrates many powerful features within an easy-to-use graphical user interface. It's no wonder that more groundwater professionals use Visual MODFLOW Pro than any other modeling package in the world!


  • Evaluate Groundwater Remediation Systems
  • Delineate Well Capture Zones
  • Simulate Natural Attenuation of Contaminated Groundwater
  • Estimate the Reductive Dechlorination of TCE, PCE and DCE in Groundwater
  • Design and Optimize Pumping Well Locations for Dewatering Projects
  • Determine Contaminant Fate and Exposure Pathways for Risk Assessment
  • Optimization of Pump & Treat Systems
  • Evaluation of Funnel & Gate Remediation Approaches
  • Simulation of Natural Attenuation Processes
  • Prediction of Plume Migration Through Aquifer Systems
  • Delineation of Wellhead Protection Areas
  • Identification of Exposure Pathways for RISK Assessment

Power Features

Visual MODFLOW Pro 'power-features" include:

  • MODFLOW-2000 (3D flow module developed by the USGS)
  • MODPATH (particle tracking module developed by USGS)
  • Zone Budget (sub regional water budgets developed by USGS)
  • MT3D (3D transport module developed by US E.P.A.)
  • RT3D (3D reactive transport module)
  • Stream Routing Package (surface water/groundwater flow)
  • WinPEST (automated calibration and sensitivity analysis)
  • VMOD 3D-Explorer (3D visualization and animation)

With Visual MODFLOW Pro, you have all the tools necessary to:

  • Graphically assign model grids, properties and boundaries,
  • Visualize model input parameters (2D or 3D views),
  • Run the flow, pathline, and transport simulations,
  • Automatically or manually calibrate the model, and
  • Display and interpret the modeling results in full 3D

For professional applications in 3D groundwater flow and contaminant transport modeling, Visual MODFLOW is the only software package you will ever need!

Proven Benefits

Our goal is to develop powerful, yet easy-to-use software that meets the needs of groundwater and environmental professionals around the world. Visual MODFLOW is an excellent example of how we have accomplished this goal by making groundwater modeling accessible for any hydrogeologist or engineer who is familiar with the basic concepts and limitations of groundwater modeling. With Visual MODFLOW, you don't need to know all of the awkward codes and cryptic data formats required by MODFLOW, nor do you need to be concerned about maintaining consistent units, keeping track of the model 'stress periods', or figuring out what VCONT and IBOUND values are. Visual MODFLOW does what every good interface should do; it takes care of these issues in an easy-to-understand and transparent manner, so you only need to be concerned with REAL DATA, REAL TIMES and COMMONLY USED UNITS.

Building, calibrating and interpreting a groundwater flow and contaminant transport model is time-consuming enough. So why make your job more difficult by using a software package you have to re-learn every time you use it? The Visual MODFLOW interface contains a logical menu structure that guides you through the steps required to build, calibrate and evaluate a groundwater flow and contaminant transport model. Download the demo today and see why thousands of groundwater modelers and environmental professionals around the world have selected Visual MODFLOW as the software of choice for their groundwater modeling projects.

Data Input

  • The most powerful and easy-to-use graphical interface available
  • Interactive model display in both plan view and cross-sectional view
  • Import AutoCAD (.dxf) files or bitmap image (.bmp) files for site base maps
  • Rotate and align the model grid over the site base map
  • Graphical grid design tools and automatic grid smoothing
  • Import variable layer surface elevations from discrete data or gridded data files
  • Import time schedules for transient boundary conditions and observation points
  • Assign multi-level observation wells and create observation groups

Simulation Capabilities

  • Now supports Modular Groundwater Optimizer (MGO)
  • Now supports Algebraic Multigrid (SAMG)
  • Full support for MODFLOW-2000, MT3DMS, RT3D, MT3D99 and WinPEST
  • Now supports MODFLOW-SURFACT
  • Full support for the Stream Routing Package
  • Seamless integration with the Win32 MODFLOW Suite
  • Interactive display of model solution convergence for on-the-fly modification of solver settings
  • graphical display of transient simulation results
  • Includes the WHS Solver (fastest and more stable than PCG2)
  • Support for the Link-Algebraic Multigrid (LMG) Package
  • Batch processing of multiple simulations for sensitivity analyses

Model Calibration

  • Comprehensive selection of calibration plots and statistics (scatter plots, residual histograms, and time series plots)
  • Automatic calibration using WinPEST 

Model Display

  • Color-shaded contouring of model properties and simulation results
  • Customizable display of contoured results, pathlines and overlay priorities
  • Detailed graphical summaries of global and local mass budgets
  • Print full-color, high-resolution plots to any printer or plotter
  • Export screen display to graphics formats such as Enhanced Windows Metafile (.emf), AutoCAD (.dxf), and ESRI Shape (.shp) files
  • Export model results to 2D or 3D ASCII text files supported by virtually ANY 3D visualization software
  • Advanced 3D visualization and animation of model input data and simulation results using the Visual MODFLOW 3D-Explorer 

Visual MODFLOW Pro What’s New

Some additional features and improvements requested by Visual MODFLOW users including:

  • Improve data export options
  • Optimization of pumping well locations
  • Improve printing options for 2D Output
  • Improve graphics export options
  • Significantly faster solver
  • Improve 2D Output graphics quality
  • Graphically assign grid cell elevations
  • Import MODFLOW data sets
  • Importing property zones and recharge zones from polygon shape files
  • Importing layer surface elevations from USGS DEM files, ESRI Grid files, and Map Info Grid files
  • Assigning layer surface elevations using a constant slope defined by a strike and dip data
  • Importing site map images from common graphics formats including .GIF, .JPG, and .TIF
  • Adjustable transparency level for imported site map images
  • Predictive Analysis using PEST-ASP  

Exporting Gridded Model Data

Visual MODFLOW v.4.0 now allows you to export virtually any model property values and simulation results to a variety of ASCII and binary data formats including:

ASCII XYZV (.TXT) - consists of four or more columns containing the X, Y and Z coordinate location
The cell coordinates can be in either world coordinates, model coordinates, or as IJK cell indexes. The data can be exported with multiple layers in a single file, or as separate files for each selected model layer.

ASCII Array (.TXT) - consists of an NR x NC array of values for each selected parameter, for each selected model layer. The data can be exported with multiple layers in a single file, or as separate files for each selected model layer.

Surfer Grid (ASCII) (.GRD) - consists of a single file for each selected parameter, for each selected layer with a user-defined grid density. Some averaging of parameter values occurs where the model grid is different than the Surfer Grid, and any inactive or dry cell values may be excluded.

Surfer Grid (Binary) (.GRD)
 - consists of a single file for each selected parameter, for each selected layer with a user-defined grid density. Some averaging of parameter values occurs where the model grid is different than the Surfer Grid, and any inactive or dry cell values may be exclude

Importing MODFLOW Data Sets

Although previous versions of Visual MODFLOW were able to import existing MODFLOW data sets, the import process often ignored important data such as Specific Storage and Specific Yield values, and it was not able to accommodate quasi 3D models containing implicitly represented aquitards. Visual MODFLOW 4.0 has a significantly improved importing process that supports both MODFLOW-2000 Groundwater Process data sets, and older data sets from MODFLOW-96 and MODFLOW-88. This process utilizes a modified version of the USGS utility (MF962MF2K.EXE) to convert MODFLOW-96 and MODFLOW-88 data sets to MODFLOW-2000 data sets, and then imports the MODFLOW-2000 data set into the Visual MODFLOW graphical environment.

Exporting and Capturing Images

One of the biggest difficulties in using Visual MODFLOW has been getting the report images into a report document. Although you could export the image to an enhanced Windows metafile, these files were not always so easy to manipulate and could not always be read by third party graphics software.

Visual MODFLOW 4.0 provides a full suite of common graphical image formats to create (.GIF, .JPG, .TIF, .PNG, and .BMP) with options for increasing the image resolution and controlling the image quality. These high-resolution images can be either exported to a separate graphics file for additional manipulation using a popular image editing program, or you can capture the enhanced image and paste it directly into the report document.

Pumping Well Optimization

Visual MODFLOW v.4.0 includes an interface supporting pumping well optimization using MGO. This program is primarily used to determine the optimal well pumping and/or injection rates at one or more wells in order to achieve a specific objective while maintaining reasonable system responses. Some of the more common scenarios include:

  • Minimizing the pumping / treatment cost of a pumping and treat groundwater remediation system while maintaining capture of a contaminant plume.
  • Minimizing the mass removal cost of a pumping and treat  groundwater remediation system while maintaining capture of a contaminant plume.
  • Maximizing the pumping rate at one or more water supply  wells while maintaining a minimum water level in the aquifer.
  • Maximizing the pumping rate at one or more water supply wells while keeping the concentration of an identified pollutant below a specified level.

The interface is setup such that the optimization problem is defined almost independent of the optimization engine you choose to work with.

MGO (Modular Groundwater Optimizer) has been developed by Dr. Chunmiao Zheng under a contract for the U.S. Dept. of Defense. This program has a public domain version available with similar optimization capabilities.

Faster Solver

Visual MODFLOW now includes the new SAMG Solver developed by the SCAI-Frauhofer Institute in Germany. This solver has been demonstrated to be from 3 to 11 time faster than the traditional PCG solver for medium size models, and much faster still for large models containing 1 million or more grid cells. Why SAMG?

Techniques for characterizing hydrogeologic parameters and assigning them to groundwater models have improved significantly. Modelers now have the tools to more precisely assign complex spatial distributions of parameters such as hydraulic conductivity with ease. However, the resulting demand on computational power has also increased significantly.

SAMG is designed to effectively address the complex distribution of sparsely distributed data, with medium or large sized grids. Simply stated, SAMG will reduce the time you spend running models, and improve model convergence so you can concentrated on other more pressing tasks.

Enviro-Base Pro

Enviro-Base Pro is an all-in-one database, designed to provide Visual MODFLOW users a wide variety of referenced hydrogeological property information. Enviro-Base Pro is now available through Visual MODFLOW Pro interface.

Enviro-Base Pro categories:

  • Soil Properties
    Including Hydraulic Conductivity, Porosity, Specific Yield,and Specific Storage.
  • Chemical Properties
    Including Viscosity, Henry's coefficient, Vapour Pressure, Log    Kow, Density, and Solubility.
  • Half-Life
  • Drinking Water Standards
  • Adsorption
  • Dispersivity

Enviro-Base Pro consolidates all categories of information pertinent to hydrogeologists into one easy-to-use, and modify, software package.

Printing Options

One of the longest running requests has been for a more customizable page layout for printing the results generated by Visual MODFLOW. The previous versions offered few options for customizing the layout and only provided a very limited amount of space for describing the image being printed. Visual MODFLOW 4.0 includes a more flexible page layout designer for adding image descriptions, project descriptions, and a company logo.

2D Color Shading

The drawing tools and algorithms used to render the color shaded contour maps of distributed data have been upgraded to include rich RGB color schemes and to allow for color map transparency in order to see underlying model features. The color schemes will be the same, but the colors themselves will be much more vibrant and the transition between colors is much smoother.

Assigning Grid Cell Elevations

One of the longest standing requested features has been to allow for graphical selection and assigning of grid cell elevations. Visual MODFLOW 4.0 has finally delivered! Now you can easily digitize the desired cell area using a polygon or rectangle, or by painting a set of cells, and then assign a constant elevation to the top or bottom of the layer surface. Built-in data validation checks prevent the layer surfaces from intersecting adjacent layer surfaces and provides suggested remedies in situations when this does occur.

Importing Property Zones and Recharge Zones from Polygon Shape Files

Visual MODFLOW v.3.0 introduced the capability of importing and interpolating Conductivity and Storage zone distributions from external data sources including XYZ ASCII files (.TXT, MS Access database files (.MDB), Excel spreadsheet files (.XLS) and ESRI Point and Line Shape files (.SHP). Visual MODFLOW v.4.0 extends this capability to more model properties including Initial Heads, Initial Concentrations, and Dispersivities. In addition, Visual MODFLOW v.4.0 also includes the ability to map property zones and recharge zones from ESRI Polygon Shape files (.SHP).

Importing and Editing Layer Surface Elevations

Visual MODFLOW v.4.0 provides a dramatically improved set of tools for importing, creating and modifying layer surface elevations for the finite difference model grid. From importing USGS DEM files, to specifying a constant slope using Strike and Dip information, no other graphical interface offers a more complete set of features for designing the model grid layer surfaces:

  • Import layer surface elevations from gridded data files 
    including USGS DEM files (.DEM), Surfer Grid files (.GRD), ESRI   Grid files (.GRD) and Map/Info Grid files (.GRD).
  • Import and interpolate sparse elevation data from XYZ
    ASCII files (.TXT), MS Access Database files (.MDB), MS Excel Spreadsheet files (.XLS), and ESRI Point Shape files (.SHP) using either Natural Neighbor, Kriging or Inverse Distance interpolation methods.
  • Add Control Points to the sparse data set in order to direct the interpolation.
  • Assign constant elevation or constant thickness values to any layer surface, or apply mathematical expressions containing existing layer surface elevations as variables.
  • Assign a constant slope to a layer surface using three points in space, or using Strike and Dip information.

The layer surface elevations may be visualized using three different view tabs:

  • The 2D Preview displays a color map of the layer surface elevations for the currently selected layer surface.
  • The 3D Preview displays a 3D wire mesh of the entire model grid.
  • The Array Preview displays a spreadsheet array of the individual   grid cell elevations for the currently selected layer surface.

Importing and Displaying Site Map Images

Previous versions of Visual MODFLOW supported importing an unlimited number of site map images, but the images were required to be provided as bitmaps, and it was only possible to view one site map at a time. Visual MODFLOW v.4.0 provides support for importing and displaying the most common image formats including .JPG, .GIF, .TIF, .PNG and .BMP. In addition, a transparency setting may be applied to the imported images in order to display multiple images simultaneously, or to view other model attributes underneath the site map image.

Predictive Analysis Using PEST-ASP

Predictive Analysis is like a form of Goal Programming, where the user asks the program to minimize or maximize a specific system response (e.g. aquifer head or groundwater concentration) by adjusting selected model parameters within a given bounds, while still maintaining the obligation of a calibrated model. By using Predictive Analysis, the modeler is able to replace the traditional trial-and-error sensitivity analysis by asking questions such as:

  • "What is the maximum contaminant concentration possible at a selected location in 50 years?"
  • "What is the maximum seepage from a section of the river due to nearby pumping?"
  • "What is the maximum rise in the water table at a selected   location due to irrigation?"

Visual MODFLOW Pro Interface

The Visual MODFLOW interface has been specifically designed to increase modeling productivity and decrease the complexities typically associated with building three-dimensional groundwater flow and contaminant transport models. The interface is divided Visual MODFLOW Pro Interfaceinto three separate modules:

Building a Model
The Run Module
The Output Module

When you open or create a file, you will be able to seamlessly switch between these modules to build or modify the model input parameters, run the simulations, and display results (in plan view or full-screen cross-section).

Each module of the Visual MODFLOW interface has the same basic screen layout as shown in the figure on the right.

The Display Control Buttons

The ability to quickly and easily switch between plan view and cross-section display of the model is a powerful feature of Visual MODFLOW that allows the user to gain a better perspective on the three-dimensional aspects of the model input parameters and simulation results. The display control buttons have the same function for each module and are located in the same location for each module. Simply select the desired display button and then click on the row, column or layer that you would like to view.

The Navigator Cube

The Navigator Cube provides a 3D schematic representation of the model grid and layers. This navigator cube provides a quick visual reference of your active position within the model domain. This is particularly useful when you are dealing with multi-layer models, or if you are viewing a model in cross-section. In addition, the active mouse location (X,Y,Z model co-ordinates and I, J, K grid coordinates) are interactively displayed below the navigator cube as you move the mouse around the screen.

Shortcut Buttons

Each menu screen of the Visual MODFLOW interface has a set of shortcut buttons located along the bottom of the screen. These buttons allow the user to quickly access some of the more common graphical functions such as zooming in or zooming out, panning the display in any direction, adding or removing overlay displays, saving the existing data file, and returning to the Main Menu.

The [F2 - 3D] shortcut button launches the Visual MODFLOW 3D-Explorer and loads the current model

Running a Visual MODFLOW Simulation

The Visual MODFLOW Run Module allows the user to select and modify the various MODFLOW, MODPATH and MT3D run-time options and start the model calculations using the Win32 MODFLOW Suite directly from within the Visual MODFLOW modeling environment.

The Run Settings

Visual MODFLOW allows you to customize the MODFLOW run settings including:

  • Initial head estimates (import from ASCII or Surfer),
  • Number of time-steps and time-step multiplier,
  • Solver selection and convergence settings,
  • Recharge layer settings, and
  • Layer-types (e.g. confined, unconfined)
  • Rewetting options*
  • Anisotropy option

* Visual MODFLOW now allows you to maintain a minimum saturated thickness for dry cells and to specify a head value in these cells equivalent to the cell bottom elevation. This enables you to run WinPEST on models even when dry cells are occurring.

MT3D run settings include:

  • Initial concentrations (import from ASCII or Surfer),
  • Advection package settings (FD, MOC, MMOC, HMOC), and
  • Simulation output times.

Advanced Settings

For the advanced users of MODFLOW, you can substitute your own manually created input data files for any MODFLOW by using the Advanced Settings. The Advanced Settings allows you to specify which files you will use from Visual MODFLOW, and which files you will substitute.

Batch Runs

Visual MODFLOW also now allows you to easily set up a batch file to run several models in succession. This is a very powerful feature that allows you to create several versions of the same model and then run the models while you are doing other tasks.

The Win32 MODFLOW Suite

Visual MODFLOW includes the Win32 MODFLOW Suite with MODFLOW-96, MODPATH, Zone Budget, MT3DMS and RT3D compiled to run as true Windows, 32-Bit applications. This unique and powerful modeling utility actually provides you with the ability to control the numerical solution process by manipulating the solver parameters and convergence criteria while the solution is in progress. In addition, it provides a real-time graphical display of the solution convergence data and a detailed graphical summary of the Zone Budget results.

After each successful run has completed, the Win32 MODFLOW Suite automatically produces all of the necessary files required for you to analyze and interpret the results, and produce full-color, report-quality graphical presentations using Visual MODFLOW’s post-processing graphical features.

Visual MODFLOW is the only modeling software package that provides a truly seamless integration with 32-Bit Windows versions of MODFLOW, MODPATH, MT3D, Zone Budget and RT3D.

Displaying and Interpreting Results

The ability to visualize and interpret the simulation results is almost as important as creating the model in the first place. In order to get the most out of the model that you build, it is critical that you have the tools necessary to properly analyze the results. Visual MODFLOW automatically reads the results created from each successful simulation and provides a comprehensive selection of graphical formats for displaying full-color results in plan view and cross-sectional views.

Contouring and Color Maps

Visual MODFLOW creates detailed contour maps of modeling Contouring and color maps of the contaminant siteresults including:

  • Heads, drawdown and multi-species concentrations
  • Water table elevations and net recharge
  • Head difference between layers and flux between layers
  • Layer elevations (top, bottom and thickness)

High-quality color shaded contouring is also available for creating presentation quality color maps of all contoured results.

Flow Velocity Vectors and Pathlines

Visual MODFLOW displays flow velocity vectors and flow pathlines (forward tracking and backward tracking). The flow velocity vectors can be used to effectively illustrate the direction and magnitude of Flow Velocity Vectors and Pathlinesthe groundwater flow velocity throughout the model domain (in plan view and cross-section). The velocity vectors can be evenly distributed throughout the model domain or added by clicking on any point in the model.

Forward tracking pathlines are used to determine the flow pathways and predict the amount of time it would take to reach a destination. Backward tracking pathlines are used to determine where the flow at a point is coming from (e.g. delineating well capture zones).

Mass Budgets for Flow and Transport

Visual MODFLOW produces detailed tabular and graphical reports of the mass balances for both the flow and mass transport simulations. These reports provide global and local summaries of the mass inflows and outflow from the system, or from a localized region of the model.


Visual MODFLOW prints full-color, high-resolution graphics to any printer or plotter supported by Windows 95/98/NT. The graphical display of the simulation results and/or input files can be printed in portrait or landscape format as a full-page image or with a title block that describes the details of the model and the results being displayed. Color-shaded contours can be printed with or without a color legend.

Visual MODFLOW also prints the on-screen display to several graphics file formats and exports results to ASCII files in 2D or 3D format.

Building a Visual MODFLOW Model

The process of building the input data file for a groundwater flow and/or transport model is often the most time-intensive and tedious task associated with groundwater modeling projects. The logical structure and layout of the Visual MODFLOW interface eliminates these difficulties by guiding the user through the sequence of steps necessary to build a groundwater flow and contaminant transport model. Once you start using Visual MODFLOW you will immediately realize the benefits of easily switching between plan view and cross-sectional view at any time. In addition, the many powerful and easy-to-use graphical tools give you all the flexibility you need to assign complex property distributions, multiple pumping wells and steady-state or transient boundary conditions.

Grid Design

Visual MODFLOW allows you to rotate the model domain over the site map (.DXF or .BMP format) to align the model grid with the site characteristics and groundwater flow direction. The finite difference grid can be modified by adding, deleting, moving and automatically refining rows, columns and layers using standard 'point-and-click' methods.

Automatic Grid Smoothing

A poorly designed grid can cause numeric instability and may lead to non-convergence of the model solution. Therefore, it is important to design the model grid with proper grid spacing to give you the level detail you need in important regions of the model, and still maintain the numerical stability you need for the solution to converge. Automatic grid smoothing is used to identify and fix regions of the grid which are poorly designed and optimize (smooth) the transition from small grid spacing to large grid spacing.

Importing Layer Elevations

Since most aquifers are not 'flat' layers, Visual MODLFOW allows you to import layer surface data from ASCII (X,Y,Z) text files or SURFER (.GRD) files. It even has a built-in check to prevent layer surfaces from intersecting each other. The layer surface elevations and thickness can be visualized using plan view contours or by viewing the model grid in cross-section.

Grid Cell Elevation Editor

A new feature in the latest version of Visual MODFLOW is the grid cell elevation editor. This tool allows you to modify the individual elevations of each cell using an array editor to modify the elevation value. The cell elevations can also be modified in cross-section using 'drag-and-drop' methods to stretch or compress a cell thickness.

Pumping Wells

Pumping wells or injection wells can be added, deleted, copied or moved using the intuitive well edit tools that allow you to graphically delineate the well screen interval and enter or import real-time pumping schedules from an ASCII text file. For sites with many pumping wells, Visual MODFLOW can also import all relevant pumping well data. Multiple well screens for a single well are easily accommodated while the pumping rate distribution between layers is automatically calculated based on the transmissivity of the layers through which it is screened. The well details and pumping schedule can be readily accessed and changed at any time. Observed head at the well can be adjusted according to the position of the well within the grid cell and radius of the well.


Visual MODFLOW defines a model property as a physical or chemical attribute of the model that remains static throughout the entire simulation. Visual MODFLOW separates the model properties into two distinct categories:

Flow Properties

Those physical model properties affecting the groundwater flow simulation. Flow properties include; hydraulic conductivity (Kx, Ky, and Kz), specific storage (Ss), specific yield (Sy), porosity and initial heads. Each of these flow properties must be defined for each cell in the model domain.

Transport Properties

Those physical and chemical model properties affecting the fate, migration and degradation of a contaminant plume in groundwater, or adsorbed to the soil. Transport properties include; dispersion (Dx, Dy and Dz), bulk density, distribution coefficient (Kd), decay constants, initial concentrations.

All model properties are assigned to individual grid cells or to zones of grid cells by either painting single cells, delineating polygons, or stretching a window around the selected grid regions. Each property zone is color-coded to visually differentiate them.

Visual MODFLOW also has many time-saving tools that allow you to copy the property distribution from a single layer to any other layer(s) to eliminate repetitive steps involved in developing the model input files. Individual property values and property zones can be edited at any time using the property database to make global modifications.

Transport PropertiesFor complex stratigraphy and varying hydraulic conductivity, it is important to be able to display and modify the model property distributions in plan view and cross-section to gain a proper perspective on the geologic characteristics of the site. Visual MODFLOW provides an active cross-sectional view allowing you to edit and modify cell properties.

Boundary Conditions

MODFLOW boundary conditions supported by Visual MODFLOW include both steady-state and transient Constant Heads, Rivers, General Heads, Drains, Recharge and Evapotranspiration. The Horizontal Flow Barrier package is also supported.

Visual MODFLOW also supports all contaminant transport boundary conditions available for the latest versions of MT3D including MT3DMS for multi-species transport, and RT3D for reactive transport and natural attenuation simulation. MT3D99, the latest commercial version of MT3D by S.S. Papadopulos is also fully supported.

Each type of boundary condition has a specific color code to differentiate them from one another. The convenient graphical tools allow you to assign these boundaries as either single cells, a polyline of cells with automatic interpolation of values, a polygon of cells, or as a rectangular window of cells. For transient simulations, real-time schedules of boundary condition values can be entered directly or imported into the time schedule from an ASCII text file.


Forward or backward tracking particles can be easily assigned for determining advective transport, preferred flow pathways and delineating well capture zones. Visual MODFLOW’s intuitive graphical tools allow you to easily assign single particles, lines of particles and a circle of particles anywhere in your model domain. These particles can be easily toggled from forward to backward tracking with the click of the mouse. For transient simulations, the release times for the particles can also be assigned to groups of particles or individually to single particles or groups of particles. This is particularly useful for demonstrating how the flow system and directions of flow change with time during varying pumping schedules or flow variation due to seasonal influences.

Observation Wells

Visual MODFLOW is the only MODFLOW modeling environment that allows you to assign multi-level observation wells, just like ones you have in the field. In addition, Visual MODFLOW is the only modeling software package that allows you to group the observation points into one or more observation groups. This grouping feature is used for interpreting the calibration data for an isolated section(s) of your model domain. This grouping feature is particularly useful for complex models simulating more than one aquifer over a large region.

The user-friendly graphical tools allow you to easily assign observation points, or import data for situations where you have temporal data for many different observation points. Once a single observation well has been entered, it can be copied or moved to any location within the model domain.

Zone Budget

The Zone Budget package allows you to produce zone-to-zone flow summaries for regions of interest in your model domain. This can be used to estimate flow contributions to a well from specific layers in your model or to predict groundwater discharge to specific sections along a river. Visual MODFLOW allows you to assign zones by painting single cells, delineating polygons or by stretching a window across the selected cells in the zone. Each zone is color coded to differentiate the various zones throughout the model domain. These zones can be copied to other layers in the model to save time and avoid unnecessary repetition.

Calibrating a Visual MODFLOW Model

Visual MODFLOW comes with an extensive selection of built-in model calibration plots and statistical summaries to give you with all the interpretation capabilities you need to properly and thoroughly analyze the model calibration data. All of the calibration plots are fully-customizable in terms of axis scaling, titles, legends, fonts, and colors. In addition, Visual MODFLOW now fully supports automated calibration using WinPEST, the only true Windows version of PEST.

Calibration Scatter Plot

Visual MODFLOW provides a scatter plot of calculated vs. observed values of heads or concentrations for the flow and contaminant transport models, respectively. This plot can be used to examine all calibration targets from the entire model domain, or it can be used to examine specified groups of observation points relating to certain sections of the model. The ability to select pre-defined groups of observation points is particularly useful for large, complex groundwater models involving several different aquifer systems.

Calibration statistics are also displayed with the graph and are updated according to the data displayed on the scatter plot.

Calibration statistics include:

  • Mean Error,
  • Absolute Mean Error,
  • Standard Deviation,
  • Root Mean Square of the Error, and
  • Normalized Root Mean Square of the Error.

The 95% confidence interval is indicated on the calculated vs. observed plot. The calibration data located within this interval can be expected to provide correct results 95% of the time.

Calibration Residuals Histogram

The calibration residuals histogram plots the normalized population of the observations vs. the interval range of normalized residual values. This plot is compared to a Student t distribution and is used to;

  1. assess the quality of the fit between the calculated and observed data; and
  2. identify any positive or negative bias in the calibration data.

Time Series Plots

For transient simulations, Visual MODFLOW creates temporal plots of calculated and observed heads, drawdown or concentrations at any observation point in the model domain. Temporal plots of calibration statistics can also be created to determine the quality of the model calibration throughout the simulation.

About WinPEST

WinPEST brings parameter estimation and predictive analysis to life! Not only can you run PEST in a friendly, intuitive Windows environment; you can study a set of comprehensive, evolving run-time displays of key PEST variables, providing a wealth of information on the progress of the parameter estimation process being undertaken by PEST. When PEST has finished execution, an additional suite of plots become available, displaying a full range of statistical and other information on calibrated parameters, calibration residuals and other PEST variables.

You will be amazed at what you can learn about your model, about the information content of your calibration dataset, and about the confidence that you can place in model results, from an examination of WinPEST’s high-impact plots. You will truly wonder how you ever got along without it!

WinPEST will:

  • Save you time and money by reducing countless hours spent calibrating
  • Improve the quality and reliability of your model
  • Improve your sensitivity analysis
  • Give you the graphical tools to interpret and display calibration parameters

Automated Calibration using WinPEST

Calibration is a crucial component to every model linking simulated model results to actual observations found in the field. Unfortunately, model calibration is a time consuming task - but not anymore!

Automated calibration of groundwater modelVisual MODFLOW now fully supports automatic calibration technology using WinPEST, the only true Windows version of PEST. WinPEST has been seamlessly integrated into Visual MODFLOW to allow you to conveniently select the model parameters you want to optimize, and then easily launch the built-in WinPEST application directly from Visual MODFLOW . The unique feature of WinPEST is that it not only modifies the MODFLOW input data files, it also modifies and updates the Visual MODFLOW data files. This makes it much more practical and convenient to re-load your model files once the automated calibration procedure is completed. While other software packages claims to support PEST, Visual MODFLOW is the only modeling environment that offers a truly seamless integration with the most powerful parameter estimation program available.

Reduce tedious hours manually adjusting model parameters to achieve acceptable calibration. Try WinPEST today!


SAMG - Algebraic Multigrid Methods for Systems

The SAMG Solver, developed by the SCAI-Frauhofer Institute in Germany, is now completely integrated within the Visual MODFLOW operating environment. SAMG is specifically designed to dramatically reduce model run-times for large models with complex parameter distributions.

SAMG has been demonstrated to be 3 to 11 times faster than the traditional PCG Solver for medium size models, and much faster still for large models containing 1 million or more grid cells!

SAMG Currently Applications:

  • Complex groundwater flow
  • Fluid flow
  • Oil reservoir simulation
  • Hydrothermal ore deposition
  • Structural mechanics


Techniques for characterizing hydrogeologic parameters and assigning them to groundwater models have improved significantly. Modelers now have the tools to more precisely assign complex spatial distributions of parameters such as hydraulic conductivity with ease. However, the resulting demand on computational power has also increased significantly.

SAMG is designed to effectively address the complex distribution of sparsely distributed data, with medium or large sized grids. Simply stated, SAMG will reduce the time you spend running models, and improve model convergence so you can concentrated on other more pressing tasks.


MT3D99 builds on the strengths of the new public-domain MT3DMS code, and includes significant new enhancements to improve performance and increase the functionality of the MT3D96 and MT3DMS codes.

Why choose MT3D as your 3D Solute Transport Simulator?

  • Fully Intergrated with Visual MODFLOW.
  • Designed designed to work directly with the industry-standard groundwater flow code MODFLOW-88 and MODFLOW-96.

Three Major Classes of Transport Solution Techniques

MT3D99 combines three major classes of transport solution techniques in a single code, namely, the standard finite difference method; the particle tracking based Eulerian-Lagrangian methods; and the higher-order finite-volume TVD method.

Wide Acceptance and Support

MT3D has been successfully applied to model thousands of sites and is widely accepted by regulators and the groundwater consulting and research community. In addition, MT3D99 is backward compatible with all previous versions of MT3D, supported by all major graphical pre- and post-processors.

The best choice for 3D solute and reactive transport modeling!

Visualization using VMOD 3D-Explorer

Visual MODFLOW Pro 3D groundwater flow and contaminant transport modeling software Features Continued

  • Create contour/color maps of model properties and simulation results
  • Present graphical summaries of global and local mass budgets
  • Create model calibration plots and statistical summaries including mean error, absolute mean error, standard deviation, and many more!
  • Full control of map overlays - save your overlay configurations and view only the overlays you require!
  • Display 3D pumping wells and observation wells
  • Represent soil property zones and boundary conditions in 3D
  • Render high resolution 3D volumetric contaminant plumes
  • Create irregular shaped cross-sections
  • 3D pathlines with time markers
  • Define 3D cut-away regions
  • Animate sequential degradation of contaminant plumes and save into AVI file format for use in Microsoft PowerPoint presentations!

Produce report-quality 3D representations of your modeling projects!


MODFLOW-SURFACT is a powerful three-dimensional finite-difference flow and transport program containing many advancements and improvements over the standard public-domain versions of MODFLOW. With more robust solution methods and enhanced simulation capabilities for handling complex saturated/unsaturated subsurface flow and transport processes, MODFLOW-SURFACT is specifically designed to address the many limitations and short-comings of the standard MODFLOW codes.


  • Simulating multiple water tables, or perched water table systems
  • Simulating steep water table gradients crossing multiple model layers
  • Simulating over-pumped wells screened across multiple model layers
  • Simulating surface water infiltration through the vadose zone to the water table
  • Simulating large water table fluctuations causing desaturation/ resaturation (drying/wetting) of grid cells
  • Simulating soil vapor flow through the unsaturated zone

The enhanced MODFLOW run engine ideally suited for complex models with variable saturated conditions!

Enviro-Base Pro

Visual MODFLOW Pro now integrates Enviro-Base Pro - an all-in-one database designed to house a variety of referenced property information used when developing groundwater models. With the ability to add and edit information, Enviro-Base Pro enables you to consolidate your technical references into one package that can be easily launched, searched and updated.

Six categories for data entry and retrieval:

  • Soil Properties
  • Adsorption
  • Dispersivity
  • Half-Life
  • Chemical Properties
  • Drinking Water Standards

An all-in-one model properties database for Visual MODFLOW Pro!

MGO - Modular Groundwater Optimizer

Groundwater remediation is associated with enormous costs. According to a recent study by the U.S. Environmental Protection Agency (1997), the remaining remediation costs for contaminated soil and groundwater in the United States are estimated at 187 billion in 1996 US dollars. A great portion of the costs is tied to pump-and-treat remedies. Through 1996, 93% of the 605 sites remaining on the EPA National Priority List (Superfund sites) had pump-and-treat remedies only, while additional 6% had a combination of pump-and-treat and in situ remedies. Thus, the problem of how to optimize the overall cost-effectiveness of existing and new pump-and-treat systems has attracted considerable attention from both industry and federal regulators in the last few years (Greenwald, 1999).

This report provides a documentation and user guide for a groundwater simulationoptimization software system, referred to as the Modular Groundwater Optimizer or MGO, that can be used to reduce the costs associated with installing and operating a pump-and-treat remediation system. Although the MGO code can be applied with no or minor modification to a variety of groundwater resource management issues and other types of remediation systems such as bioremediation, the focus of this report is on the use of MGO for optimization of groundwater pump-and-treat systems.!

What’s New in Visual MODFLOW Version 4.1?

The main interface for Visual MODFLOW version 4.1 has much of the same user-friendly look and feel as previous versions of Visual MODFLOW, but what’s “under the hood” has been improved to give users more powerful tools for entering, modifying, analyzing, and presenting groundwater modeling data. You now have the ability to effectively tackle seawater intrusion projects, with direct access to powerful solvers such as the new GMG Solver.

In addition, Visual MODFLOW version 4.1 have streamlined the GUI to improve the overall work flow during model development and you can expand your project scopes and expect top-performance with even the most complex models!

USGS SEAWAT Implementation

The USGS SEAWAT 2000 engine has now been included in Visual MODFLOW Pro and Visual MODFLOW Premium, allowing modeling of variable density flow such as seawater intrusion modeling problems. SEAWAT combines a flow code (MODFLOW) with a solute-transport code (MT3DMS) to form a single program that solves the coupled flow and solute-transport equations. It formulates flow equations using mass conservation instead of volume USGS SEAWAT 2000conservation (MODFLOW-2000).

The SEAWAT Engine has also been integrated with the WinPEST parameter optimization component of Visual MODFLOW Pro & Visual MODFLOW Premium. No other MODFLOW modeling package offers this integrated combination.

Improved Project Creation Wizard, and Graphical User Interface

The Visual MODFLOW project creation wizard has been redesigned to assist the user with selecting the most appropriate Flow and Transport Numeric Engines for a particular project, using a “Flow Type selector” linked to the available Transport engines. The wizard now guides the user through selecting and entering Project Information, Flow engines and options, Transport engines and options, Transport species, and Run time options, all in one easy-to-use interface.

VCONT Calculation Options Implemented

Users now have the option (depending on the Layer Property package selected for their model), to choose between VCONT values calculated from the Ground Surface (top of layer 1), or from the Initial Heads.

MT3DMS Version Update

The MT3DMS Engine (version 4.5) has been incorporated into Visual MODFLOW version 4.1. .


An updated version of the USGS MODFLOW 2000 Engine (version 1.15.00) has been incorporated into Visual MODFLOW version 4.1.

SAMG Solver Update

The latest version of the Algebraic Multigrid Methods for Systems (SAMG) solver, optimized for MODFLOW, has been implemented. The SAMG solver has been demonstrated to be 3 to 11 times faster than the traditional PCG solver for medium sized models, and even faster for large models containing one million or more grid cells. SAMG is only available in Visual MODFLOW Premium.

GMG Solver Implementation

The new Geometric Multigrid Solver (GMG) solver from USGS has been integrated with the MODFLOW-2000 and SEAWAT-2000 Engines. In contrast to the AMG solver, the preconditioning in GMG is based on the geometric multi-grid solver method. The GMG solver has been demonstrated to greatly reduce model run times relative to other solvers using a comparable amount of memory. The GMG solver is available only with Visual MODFLOW Pro and Visual MODFLOW Premium.