New Features in Version 5.03 of HYDRUS (compared to version 5.02)
See also the latest changes and new features in History of changes and new features in HYDRUS.
- PFAS with kinetic (both linear and nonlinear) sorption (a two-site sorption model) to the air-water interface 1D.
- PFAS, Surfactant, and Reservoir BC (3D) were implemented into HyPar to make it compatible with the standard computational modules.
- Campbell’s thermal conductivity model was added to 2D and 3D models.
- Dispersive solute fluxes were included into the solute fluxes across mesh-lines into HP2.
- Fluxes across cross-sections in the Wetland module.
- Optimization of graphical display of results for large projects (where the number of mesh nodes N > 1,000,000). A huge speedup has been achieved, displaying results can now be up to 100 - 1000 times faster than in HYDRUS 5.02 (depending on the specific project).
- Import of external FE-meshes. HYDRUS 5.03 can import an external three-dimensional FE-mesh in the VTK Unstructured Mesh format (*.vtu file), which enables working with 3D transport domains created in other programs. The imported mesh can used for defining all input data (domain properties, boundary and initial conditions) as well as running the calculation and post-processing. Meshes in many other formats (OpenFOAM, EnSight, ANSYS, FLUENT,…) can first be loaded into the Paraview program and then saved in VTU format for HYDRUS.
- New object type “Mesh-Surface” - helper object for calculating fluxes through any surface in 3D domains. Mesh Surfaces can be defined either directly on the FE-mesh or with the help of topological objects (Surfaces).
- Calculation of fluxes through Mesh-Surfaces in 3D domains - similar to the calculation of fluxes through Mesh Lines in 2D domains.
- New option to define Mesh Lines also on topological objects (Curves)
- New option for 1D projects: Import of Initial Conditions from results of another project.
- Conversion of 1D projects to 2D/3D and vice versa.
- New option to quickly invert colors in the color scale for results(“Reverse Colors”).
New Features in Version 5.02 of HYDRUS (compared to version 5.01)
- The PFAS Module in 3D.
- The PFAS computational modules print the air-water interfacial area, Ae. Ae is printed into the Nod_inf.out file in 1D instead of the v/KsTop column. Ae is printed into the new binary output file AWIArea.out in 2D and 3D.
- The PFAS computational modules can display the air-water interfacial area under Results.
- Users can display solute concentrations on the air-water interfacial area in the HYDRUS GUI (under Results) by selecting a concentration option on the View Tab of the Navigator Bar.
- Users can display different modes (liquid, solid, AWI) of solute concentrations in the Profile Information Graph (1D).
- A tool for entering the working plane graphically by clicking on any 3D surface.
New Features in Version 5 of HYDRUS (compared to version 3 of HYDRUS (2D/3D) and version 4 of HYDRUS-1D)
New Features and Changes in HYDRUS 5.01:
- The PFAS Module (in 1D and 2D): The PFAS module considers sorption to the air-water interface and the effects of the solution concentration on retention and viscosity. The PFAS module can thus be used to simulate the fate and transport of PFAS chemicals (Silva et al., 2021).
- The Particle Tracking Module (in 1D): This module tracks the position of hypothetical particles, which are either initially defined in the soil profile, or are released at its boundaries. The results of this module can be used to calculate soil water travel times and water age for different locations in the soil profile.
- The COSMIC Module (in 1D): The COSMIC module developed by Brunetti et al. [2019] calculates above ground neutron fluxes used the physically-based COsmic-ray Soil Moisture Interaction Code (COSMIC) of Shuttleworth et al. [2013].
- The DPU module (in 1D and 2D): The Dynamic Plant Uptake (DPU) module developed by Brunetti et al. [2019, 2021, 2022] simulates the translocation and transformation of neutral compounds in the soil-plant domain.
- The UnsatChem module (in 3D): The module simulates the fate and transport of major ion, and can evaluate problems of soil salinity and sodicity. We have implemented this module also in 3D (in addition to 1D and 2D implementations previously available).
- The C-Ride module (1D): The C-Ride module simulates one- and two-dimensional variably-saturated water flow, colloid transport, and colloid-facilitated solute transport in porous media. The module accounts for transient variably-saturated water flow, and for both colloid and solute movement due to advection, diffusion, and dispersion, as well as for solute movement facilitated by colloid transport. Detailed description of the C-Ride Module is given in the C-Ride user manual [Šimůnek et al., 2012, 2022]. We have implemented this module also in 1D (in addition to the previously available 2D implementation).
- The transport of environmental isotopes without fractionation or with constant fractionation during evaporation (Stumpp et al., 2012) (in 1D).
- The Reservoir BC in 3D.
- The number of Print Times was increased to 10,000.
- New graphical capabilities, such as z-t graphs of selected variables.

Click to enlarge.
New Features in version 3.01 of HYDRUS (2D/3D) (compared to version 2.05)
New Features and Changes:
- Reservoir Boundary Condition
- Root Growth
- Flowing particles in 3D projects
- Streamlines
- Graphical Manipulator
- Clipping and Slicing
- Velocity vectors in raster points
- New options for Mesh-Sections and selection of mesh entities
- Inactive objects
- Named Views
- Numbering of isolines
- Export data to Paraview
- Optimization and 64-bit version
Detailed description of new features and changes in Version 3.01 of HYDRUS (2D/3D) are given in Šimůnek et al. (2018).
New Features in version 2.05 of HYDRUS 2D/3D (compared to version 2.04)
New Features and Changes:
- The new SLOPE Cube (Slope Stability) module - a supplemental module of the HYDRUS (2D) software package to simulate two-dimensional transient fields of soil moisture, soil suction, suction stress, total and effective stresses, and local factor of safety.
Fixed Errors:
- Changes of auxiliary objects (dimensions, comments, etc.) lead to deleting results, which actually was not necessary.
- Units in the field capacity calculations.
- Incorrect colors of materials for more than 20 materials.
- Error in the GUI in calculating the root distribution function Beta.
- Error in the GUI in specifying osmotic coefficients for the stress response function for HP2.
- Several other minor errors (see History of changes in HYDRUS 2.xx)
New Features in version 2.04 of HYDRUS 2D/3D (compared to version 2.03)
New Features and Changes:
- The new HYPAR module. HYPAR is a parallelized version of the standard two‐dimensional and three‐dimensional HYDRUS computational modules.
- The new Slope module. The module analyses the stability of generally layered two‐dimensional soil slopes including the presence of water modelled using the pore pressure automatically imported from HYDRUS results.
- The on‐line deactivation no longer requires a password.
- HYDRUS can automatically check for new updates (using pc‐progress.com website) and informs the user if an update is available.
Fixed Errors:
- Boundary surfaces of internal solids (solids in solids) were incorrectly included in domain boundaries (boundary conditions).
- Several other minor errors (see History of changes in HYDRUS 2.xx)
New Features in version 2.03 of HYDRUS 2D/3D (compared to version 2.02)
New Features and Changes:
- Using new fonts compatible with the Chinese, Japanese and other similar Windows systems. This should prevent cutting off text in dialogs and other parts of the GUI.
- Export of isolines (available only in 3D-Professional). Knowledge of an exact position of certain isolines (e.g., h=0 for groundwater table; c=c_min to define an extent of pollution) is important for many applications (e.g., slope stability).
- Import if various quantities (pressure head or concentration initial conditions, etc.) from values defined at scattered 2D/3D points.
- Allowing triggered irrigation in the UnsatChem module.
- Initial conditions for water flow can be set equal to Field Capacity (Twarakavi et al., 2009).
- Display of wetting hydraulic functions for hysteretic soils.
- The maximum time step in the Wetland module is limited to avoid concentration overshoots.
Fixed Errors:
- HYDRUS activation: It was not possible to set the expiration date after July 10, 2014
- Several other minor errors (see History of changes in HYDRUS 2.xx)
New Features in version 2.02 of HYDRUS 2D/3D (compared to version 2.01)
New Features and Changes (related to GUI):
- GUI look has been improved by using true-color icons and advanced docking-panel layout.
- Added new function: File -> Import and Export -> Export FE-Mesh. This function exports FE-mesh to a text file that includes information about links between geometrical objects and corresponding FE-mesh elements.
- Added new function: File -> Import and Export -> Export Current Quantity. This function exports values of the current quantity (displayed in the active view) into a text file. The function exports values only for visible nodes (one can use FE-Mesh Sections to export values for any part of the domain).
- Improvement: if there is a difference between values defined on GeoObj and FE-mesh, the program displays yellow arrow pointing to the first difference.
- Improvement:Defining objects on geometric objects is possible even after removing some FE-elements from the mesh. Values are then transferred from GeoObj to remaining mesh nodes or elements.
- Added new option: Authorization of HYDRUS using a hardware key (HASP). Starting with version 2.02, the software key (activation) can be used to authorize only separate computers, while a Hardware Key is required for the network installation.
- Initial Conditions for water flow can be set equal to Field Capacity (Twarakavi et al., 2009) (in version 2.02.0700).
- Display of wetting hydraulic functions for hysteretic soils (in version 2.02.0700).
New Features and Changes (related to computational modules):
- Updated Unsatchem Module.
- The new DualPerm module simulating flow and transport in dual-permeability porous media.
- The new C-Ride module simulating colloid transport and colloid-facilitated solute transport.
- The new HP2 module simulating treansport and biogeochemical reactions.
New Features in version 2.01 of HYDRUS 2D/3D (compared to version 1.x)
New Features and Changes (related to GUI):
- Support for complex General three-dimensional geometries (3D-Professional Level).
- Domain Properties, Initial Conditions, and Boundary Conditions can be specified on Geometric Objects (defining the transport domain) rather than on the finite element mesh.
- New FE-mesh generator for unstructured 3D meshes. Supports mesh refinements and stretching.
- Background layers facilitating graphical input of data.
- Import of geometry and background layers from a number of formats (DXF, STL, TIN, BMP, ...)
- Import of various quantities (e.g., domain properties, initial and boundary conditions) from another HYDRUS projects even with (slightly) different geometry or FE mesh.
- Support of ParSWMS (a parallelized version of SWMS_3D).
- Support of UNSATCHEM (a module simulating transport of and reactions between major ions).
- Support of a new CWM1 constructed wetland module.
- The Mass Balance (Inverse) Information dialog window enables to display texts larger than the capacity of the Edit window.
- Constructed Wetland Parameters commands added to the main menu and navigation tree.
- Root distribution can be specified using GUI parallel with the slope of hillslopes.
- Display of results using Isosurfaces.
- On-line activation and deactivation. HYDRUS 2.x can be activated and/or deactivated via internet without asking for activation codes.
New Features and Changes (related to computational modules):
- New, more efficient algorithm for particle tracking. Time-step control to guarantee smooth particle paths.
- Initial conditions can be specified in the total solute mass (previously only liquid phase concentrations were allowed).
- Initial equilibration of nonequilibrium solute phases with equilibrium solute phase (given in initial conditions).
- Gradient Boundary Conditions (users can specify other than unit (free drainage) gradient boundary conditions).
- A subsurface drip boundary condition (with a drip characteristic function reducing irrigation flux based on the back pressure).
- A surface drip boundary condition with dynamic wetting radius.
- A seepage face boundary condition with a specified pressure head.
- Triggered Irrigation - irrigation is triggered by HYDRUS when the pressure head at a particular observation node drops below a specified value.
- Time-variable internal pressure head or flux nodal sinks/sources (previously only constant internal sinks/sources).
- Fluxes across meshlines in the computational module for multiple solutes (previously only for one solute).
- HYDRUS calculates and reports surface runoff, evaporation, and infiltration fluxes for the atmospheric boundary.
- Water content dependence of solute reactions parameters using the Walker’s [1974] formula was implemented. (Walker, A., A simulation model for prediction of herbicide persistence, J. Environ. Quality, 3(4), 396-401, 1974.)
- An option to consider root solute uptake, including both passive and active uptake [Šimunek and Hopmans, 2009]. See also FAQ18.
- The Per Moldrup’s tortuosity models [Moldrup et al., 1997, 2000] were implemented as an alternative to the Millington and Quirk [1960] model.
- An option to use a set of Boundary Condition records multiple times.
- Executable programs are about 1.5 - 3 times faster than in the standard version due to the loop vectorization.
- A new CWM1 constructed wetland module (in addition to the CW2D module).
- New options related to the fumigant transport (e.g., removal of tarp, temperature dependent tarp properties, additional injection of fumigant).
Fixed Errors:
- Fixed error: The Wetland module had a wrong format statement when writing the CumQ.out file.
- Fixed error: FE-mesh generation could fail if stretching factors were >1 and the domain boundary contained polylines and (at the same time) splines or arcs.
- Fixed error: Activation energy coefficients in the temperature dependence functions were incorrectly converted when time units changed.
- Fixed error: Unit conversion of the area associated with transpiration was incorrect when length units changed.
- Fixed error: Conversion of some first- and zero-order rate constants with respect to length units.
New Features in previous versions of HYDRUS 2D/3D
New Features in version 1.0 of HYDRUS 2D/3D compared to Hydrus-2D and a list of all changes made in various HYDRUS versions (from 1.0 to 1.11) can be found in the History of Changes in Version 1.