
AquiMod is a simple, lumped-catchment groundwater model. It simulates groundwater-level time series at a point by linking simple algorithms of soil drainage, unsaturated-zone flow and groundwater flow. It takes time series of rainfall and potential evapotranspiration as input and produces a time series of groundwater level. Hydrographs of flows through the outlets of the groundwater store are also generated, which can potentially be related to river flow measurements.
AquiMod has been applied widely in the UK and internationally for applications including operational seasonal and flood forecasting, groundwater level record reconstruction and climate change impact assessment. It has also been used to teach concepts of subsurface flow and modelling to a range of audiences including earth science undergraduates and water practitioners.

Example groundwater level time-series simulation using AquiMod (cyan) and observed levels (black). BGS Β© 51ΑΤΖζ.
The software is easy to use and should be accessible to users who are new to the field of groundwater or hydrological modelling. The model is configured using a series of text files and run through the command line.
Key features of AquiMod
- Fast simulation of groundwater-level time series
- User-defined time stepping for flexibility
- Monte Carlo parameter sampling
- Automated global parameter optimisation (new to AquiMod 2!)
- Modular structure with multiple process representations
- Choice of objective functions to evaluate model efficiency
AquiMod 2
Since the release of AquiMod 1.0, the AquiMod development team have made a number of improvements to the source code. In 2022, these were incorporated into a new public release of the AquiMod groundwater modelling software: AquiMod 2. The developments include:
- setup wizard for easier installation/uninstallation across Windows versions
- two new soil zone components and four new saturated zone components
- streamlining of Weibull unsaturated zone component for faster runtime
- new F-score and weighted NSE-F-score objective functions
- new shuffled complex evolution mode for global parameter optimisation
- ability to impose soil moisture conditions
- ability to calibrate and evaluate against soil moisture data
- new, automated generation of template input files when not provided by the user
- improved handling and reporting of user input errors
A precompiled 32-bit binary distribution of AquiMod 2 for the Windows operating system can be downloaded for free along with the user manual which includes example applications and tutorials.

Generalised structure of AquiMod. BGS Β© 51ΑΤΖζ.
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- Operational groundwater level forecasting including groundwater flood forecasting
- Impacts of climate change on groundwater levels: (FFGL) and (eFLaG) projects
- Groundwater level reconstruction and drought analysis: project
- Simulation of
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If you require further information, wish to report a problem with the software or have suggestions as to how we can improve it, please contact the AquiMod development team.