Processing Modflow 11 is a graphical user interface for flow and transport simulations of surface water and groundwater with MODFLOW, GSFLOW, MT3D-USGS, SEAWAT, MODPATH, and PEST. Processing Modflow 11 comes with the supported models/codes and a map-based user interface that can display online basemaps and GIS shapefiles along with the model grids and results (such as contour maps, flow vectors, pathlines, etc.) of multiple models. The interface enables users to construct, calibrate, and run models as well as visualize results. Processing Modflow 11 can import MODFLOW models and MT3D models from their standard input files. The main features of Processing Modflow 11 are listed below. Scroll down for more details. Click next to an item to display its associated image.

User Guide — Download SoftwareRecommended CitationsRelease Notes

Main Features

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.

GSFLOW

GSFLOW is a coupled Groundwater and Surface-water flow model based on the integration of the USGS Precipitation-Runoff Modeling System (PRMS-V) and the USGS Modular Groundwater Flow Model (MODFLOW-NWT). GSFLOW was developed to simulate coupled groundwater/surface-water flow in one or more watersheds by simultaneously simulating flow across the land surface, within subsurface saturated and unsaturated materials, and within streams and lakes. GSFLOW can be used to evaluate the effects of land-use change, climate variability, and groundwater withdrawals on surface and subsurface flow for watersheds that range from a few square kilometers to several thousand square kilometers, and for time periods that range from months to several decades. The supported GSFLOW modules are listed below.

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. The Variable-Density Flow (VDF) Process of SEAWAT allows 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 is also included in SEAWAT 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, therefore SEAWAT is also able to simulate solute and heat transport simultaneously. The supported packages are listed below.

MODPATH

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 seamlessly integrates MODPATH with the following options.

Zone Budget

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 11. 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.

PEST, BeoPEST, and PEST++

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 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). Similarly, all members of the PEST++ software suite support parallelization. PM supports PESTPP-IESnew and PESTPP-GLMnew. The former can be used together with the Pilot Points and Kriging methods to generate calibration realizations with realistic distributions of aquifer parameters.

Streamflow new , Lake Stage new , and Multi-layer new head and drawdown observations at user-specified observation points may be used with PEST, BeoPEST, and PEST++. Below is a list of estimable parameters when running PEST, BeoPEST or PEST++ from Processing Modflow. The estimable aquifer parameters depend on the selection of the internal flow package and layer types. See the user guide for details. Aquifer parameters can be calibrated in the form of zones of piecewise uniformity or newPilot points.

System Requirements

Notes

1 Native input data files of supported packages may be imported, except for the OC and LMT packages. Other restrictions may apply, for example SFR2 defined with parameters are not supported.
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 on your computer. If the application starts successfully, your graphics adapter is supported.