Visual MODFLOW Flex 8.0
Groundwater Flow & Contaminant Transport Modeling Software
Visual MODFLOW Flex brings together industry-standard codes for groundwater flow and contaminant transport, essential analysis and calibration tools, and stunning 3D visualization capabilities in a single environment.

What's New in Visual MODFLOW Flex 8.0
Experience the new version release of Visual MODFLOW Flex 8.0
See what was included in Visual MODFLOW Flex 7.0
For a complete version history, see the Visual MODFLOW Flex readme file
Observations
You can now add more types of observations to your groundwater modeling projects:
- Observation Types: the following observation types are now supported
- Wells/Points: head, concentration
- Boundary Condition Flow: net volumetric flow exchange between groundwater and a specified boundary condition
- ZoneBudget Zone Flow: net volumetric flow exchange of groundwater in/out of a specified zone, between a specified zone and another zone or a specified boundary condition type
- Stream (SFR): stage, depth, outflow, head difference between stream midpoint and associated groundwater cell centroid, flow diverted (diversion segments only ), groundwater head, streambed seepage through the unsaturated zone
- Lakes (LAK): stage, volume, inflow, outflow
Calibration and Run Result Visualization
- Visual MODFLOW Flex includes a new model results dashboard to facilitate model calibration and results interpretation:
- Model Dashboard: model observations and associated model results can be displayed in the new model results dashboard which includes dynamic tabulation and charting of results:
- Tabulated results: observations and corresponding simulated results are presented in a tabular format with dynamic filtering. Tabulated observations include observation metadata, including time, location, observation group/type, model layer, and conductivity zone so that you can quickly display all the data or limit the view to what is relevant.
- Charts: simultaneously display one or more charts including:
- simulated vs observed values to evaluate model calibration/history matching
- time-series to display and evaluate transient result
- Text Outputs: all observations and associated simulated results are output as tab-separated variable text files for use in both Visual MODFLOW Flex and in external applications.
- Flooded Cells: Display cells with simulated heads above the top of the model as a flood depth map or as a solid color to facilitate model calibration and interpretation:
- Easily switch the location of subviews in Flex Viewers so that you can customize the layout.
- Model Dashboard: model observations and associated model results can be displayed in the new model results dashboard which includes dynamic tabulation and charting of results:
Packages and Model Runs
Visual MODFLOW Flex includes the following improvements for working with your models:
- Single Engine Runs: run a secondary model such as transport, particle track, or zone budget simulation without having to rerun your flow model.
- Update Solvers: update your flow model solvers without having to retranslate your whole model
- Copy Property Zones: copy/paste zones from one material property zone type to another so that you can more easily have consistent material zones across property types such as conductivity, storage, and transport parameters
- Default SMS Settings: the default settings for the SMS solver package in MODFLOW-USG have been updated based on recommendations by the author of MODFLOW-USG
- Gage Package: gage package is supported in models using the surface water network workflows for streams (SFR) and lakes (LAK).
Surface Water Workflow
Visual MODFLOW Flex includes a new calibration dashboard:
- Conceptual Workflow: Build surface water stream and lake networks in a conceptual model and convert it to numerical models
- Clone Workflow: surface water workflows are copied into applicable runs when editing a grid or cloning a model run
Data Handling
Greater control over your project modeling data:
- Data Operations: data objects use the expression builder, facilitating greater control and flexibility when adjusting data object elevations for surfaces, points, polylines, and polygons.
- Expression Builder functions: added a function called ifgaps() to handle expressions with non-overlapping surfaces – now you can combine surfaces with different extents/scales such as regional and site surfaces using a single expression.
- Horizons: are now treated the same as other surfaces: they can be shown in 2D views with control over display settings
- Cell Inspector Feedback: Typing a cell ID in the cell inspector provides (optional) feedback on where the specified cell is located in the active view
- Export more data objects:
- Grids: shapefile,
- Output Comparisons: shapefile, contours, and surface
- Horizons: surfaces
- Water Table: surface
Performance, Usability, and Other Enhancements
Improved speed and performance for the following:
- Loading and editing model properties and boundary conditions in larger models
- Using the Cell inspector
- Model Translation
Greater control over your project modeling data:
- Backup your project and related files as a zip file from the Main Menu to archive your project or easily share it with colleagues.
- Generate all grid types from the Model Domain context menu of conceptual models
- Define particles around screens of non-vertical wells in the 3D plane perpendicular to the well stem
Defects Addressed
The following issues have been addressed:
- Changing numeric values in color ramp settings has no effect
- Improper validation when importing a model that uses the BCF package having inactive cells with 0 thickness causes model runs to fail.
- Pilot Point values not correctly assigned using property values from the model leading to issues with preferred-value Tikhonov regularization
- PEST implementation incorrectly assumed pilot points were present in all layers and was corrected to only assign pilot points to cells/layers in their respective zone.
- ZoneBudget fails to run if Conceptual Model name has leading or trailing spaces
- Flow model translation fails if the SFR workflow schedule/data is empty. Flex will now skip SFR translation in this case.
- Project files grow after each save
- SFR2 Feature layer order and symbology does not persist after closing and reopening the project
- WEL package disables MNW2 translation in some cases
- Error assigning MNW wells to numerical model in certain cases
- Flex fails to create child grids in one-layer grids
- PEST workflow does not create Variograms when some layers do not contain a zone.
- Quality and aspect ratio of exported images from 2D views was incorrect
- DRT package not included in run using Advanced translation settings
- Layer View is corrupted in some cases when viewing T=1 in View Maps step
- Surface Water Workflows are not included in cloned runs present in the original run
- Insufficient validation at translation may lead to LGR models that fail because dry cells propagate to the interface between parent and child grids.
- MODFLOW-SURFACT BCF package translation formatting is incorrect for layers with negative elevations
- Transport run window only reports up to 9999 time steps. The max number of reported time steps for a transport run is now 100,000,000.
- Cannot extract a subgrid if the project has been run previously, but not in the current session
- Importing well objects having measured depths resulting in negative elevations fails
- During transport engine translation, .BTN file does not always honor the ‘Simulation time length’ value entered in MT3DMS translation settings
- When a single 2D sub view is active at the view maps step, the view toolbar buttons may be hidden
- Grid color cannot be changed in Flex 2D subviews
- Export null values in dry cells/inactive cells does not respect user selection
- Error while trying to import UCN files with unknown units
- Error opening constant concentration in standalone viewers
- Error trying to access color settings in certain numerical workflows
- SFR dataset2 is missing cells during translation of model with certain topological configurations