Processing Modflow X comes with the supported models/codes and a map-based user interface that can display online basemaps and shapefiles along with the grids and results of multiple models. The interface enables users to construct, calibrate, and run models as well as visualize results. The main features of Processing Modflow X are listed below. Scroll down for more details. Click next to an item to display its associated image.
Refer to the user guide for a complete description or click here to download.
MODPATH (particle tracking)
ZoneBudget (water budget calculation)
PEST (parameter estimation)
BeoPEST (parallel parameter estimation)
Model Data Input/Output Formats
2D Modflow Array
3D Modflow Array
SURFER GRD File
Comma-Separated Values File
Multimedia Output Formats
Video (model animation)
Up to 200 Layers
Up to 5000 x 5000 cells per layer
Up to 100 transport species
No upper limit on number of stress periods
Sink & Source Mixing Package
Prescribed Fluid Density
Prescribed Dynamic Viscosity
MODFLOW-2005 and MODFLOW-NWT
MODFLOW-2005 simulates steady and nonsteady flow in an irregularly shaped flow system in which aquifer layers can be confined, unconfined, or a combination of confined and unconfined. Flow from external stresses, such as flow to wells, areal recharge, evapotranspiration, flow to drains, and flow through river beds, can be simulated. Hydraulic conductivities or transmissivities for any layer may differ spatially and be anisotropic, and the storage coefficient may be heterogeneous. Specified head and specified flux boundaries can be simulated as can a head dependent flux across the model’s outer boundary. MODFLOW-NWT is a Newton-Raphson formulation for MODFLOW-2005 to improve solution of unconfined groundwater-flow problems. MODFLOW-NWT is intended for solving problems involving drying and rewetting nonlinearities of the unconfined groundwater-flow equation. The supported packages of MODFLOW-2005 and MODFLOW-NWT are listed below.
Output Control (OC)
Flow-Transport Link (LMT)
Internal Flow Packages
Block-Centered Flow (BCF)
Layer-Property Flow (LPF)
Upstream Weighting (UPW)
Drain with Return Flow (DRT1)
Evapotranspiration with a Segmented Function (ETS1)
Flow and Head Boundary (FHB)
General-Head Boundary (GHB)
Horizontal-Flow Barrier (HFB6)
Multi-Node Well (MNW1)
Time Variant Specified Head (CHD)
Generic Multigrid (GMG)
Preconditioned Conjugate Gradient (PCG)
PCG with Improved Nonlinear Control (PCGN)
Strongly Implicit Procedure (SIP)
MT3DMS, MT3D-USGS, and SEAWAT
MT3DMS is a modular three-dimensional multispecies transport model for simulation of advection, dispersion and reactions of contaminants in groundwater systems. MT3D-USGS is a U.S. Geological Survey updated release of the groundwater solute transport code MT3DMS. MT3D-USGS has a comprehensive set of options and capabilities for simulating advection, dispersion/diffusion, and chemical reactions of contaminants in groundwater flow systems. SEAWAT is a coupled version of MODFLOW and MT3DMS designed to simulate three dimensional, variable-density, saturated ground-water flow. Flexible equations were added to the program to allow fluid density to be calculated as a function of one or more species. Fluid density may also be calculated as a function of fluid pressure. The effect of fluid viscosity variations on ground-water flow was included as an option. Fluid viscosity can be calculated as a function of one or more species, and the program includes additional functions for representing the dependence on temperature. Although MT3DMS and SEAWAT are not explicitly designed to simulate heat transport, temperature can be simulated as one of the species by entering appropriate transport coefficients. The supported packages are listed below.
This package is responsible for model discretization and I/O Controls.
This package simulates the transport of miscible contaminants at the same velocity as the groundwater.
This package simulates dispersion caused by mechanical dispersion and by molecular diffusion driven by concentration gradients.
This package simulates sorption and kinetic reactions. Supported sorption types include equilibrium (linear, Freundlich, Langmuir), non-equilibrium (first-order reversible kinetic), and dual-domain mass transfer (with or without sorption). Supported kinetic reaction types include zero-order reaction, first-order irreversible reaction, first-order chain reaction, Monod kinetic reaction. Custom reactions may also be simulated.
This package of SEAWAT solves the variable-density ground-water flow equation.
The Viscosity package of SEAWAT simulates effects of viscosity variations.
GCG Solver Package (GCG)
The GCG Solver is a general-purpose iterative solver based on the generalized conjugate gradient method for solving the system of the transport equations
MODPATH is a particle-tracking post-processing program designed to work with MODFLOW. MODPATH uses a semi-analytical particle tracking scheme that allows an analytical expression of the particle’s flow path to be obtained within each finite-difference grid cell. Particle paths are computed by tracking particles from one cell to the next until the particle reaches a boundary, an internal sink/source, or satisfies some other termination criterion. Processing Modflow X seamlessly integrates MODPATH with the following options.
Forward or Backward Tracking Directions
Customizable Particle Release Times
Customizable Retardation Factors
Adjustable Tracking Time Steps
Adjustable Tracking Time Limits
Adjustable Particle Stop Options
Particle: Color, Size, Opacity
Time Mark: Color, Size, Opacity
Pathline: Line Width, Opacity, Color by Particle or Layer
Export Pathlines to Shapefile
Export Time Marks to Shapefile
Export Starting Points to Shapefile
Export Starting Points to CSV File
Import Starting Points from CSV File
Zonebudget is a computer program that computes subregional water budgets using results from the MODFLOW ground-water flow model. The user designates the subregions by specifying zone numbers with the Cell-by-Cell, Polyline, and Polygon Tools of Processing Modflow X. A separate budget is computed for each zone. The budget for a zone includes a component of flow between each adjacent zone. All three output formats of Zonebudget are supported.
This listing file contains the water budget of all zones of individual time steps at which flow terms are saved in the budget file.
For each time, for which the flow terms are saved in the budget file, there is one line for each in-flow term and each out-flow term along with totals. The zones are displayed in columns, so one table displays all zones. This makes it easy to compare any budget term for all the different zones.
This file displays the complete budget for one zone and one time in a single line. Each column has a separate inflow or outflow budget term. The rows can be sorted by time within the spreadsheet program, which makes it possible to easily see how each term changes with time.
PEST and BeoPEST
PEST is the industry standard software package for parameter estimation and uncertainty analysis of complex environmental and other computer models. BeoPEST is a special version of Parallel PEST inspired by Beowulf Clusters. A Beowulf Cluster contains several computers that are tied together using a reasonably fast network. When running BeoPEST within Processing Modflow X on a multicore computer, it is configured to run solution agents on individual CPU cores to accelerate the parameter estimation process (by solving the Jacobian matrix parallelly). Both head and drawdown observations at user-specified observation points may be used with PEST or BeoPEST. Below is a list of estimable parameters when running PEST or BeoPEST from Processing Modflow X. The estimable aquifer parameters depend on the selection of the internal flow package and layer types. See the user guide for details.
Horizontal hydraulic conductivity
Vertical hydraulic conductivity
Drain (DRN) Package
Drain with Return Flow (DRT) Package
Maximum ET Flux
Evapotranspiration Segments (ETS) Package
Maximum ET Flux
General-Head Boundary (GHB) Package
Horizontal-Flow Barrier (HBF) Package
Interbed Storage (IBS) Package
Inelastic Storage Factor
Recharge (RCH) Package
Reservoir (RES1) Package
Vertical hydraulic conductivity of reservoir bed
Stream (STR) Package
Unsaturated-Zone Flow (UZF1) Package
Well (WEL) Package
32-bit or 64-bit
4 GB or more.
500 MB for the application and examples.
Supports OpenGL 2.1 or higher4
Required for licensing and online basemaps
1 Native input data files of supported packages may be imported, except for the MNW1, OC, and LMT packages.
2 The model discretization limit subjects to the available physical resources of the computer, such as memory, disk space, and CPU speed. In general, the number of cells and layers of a model should be kept as small as possible. Unnecessary use of excessively large number of cells is not advised.
3 See here or here for lists of supported basemaps.
4 Most 3D graphics adapters are supported. To test the compatibility of your graphic adapter, download and run the Processing Modflow X on your computer. If the application starts successfully, your graphics adapter is supported.