Collaborating Organisations: Goyder Institute, Flinders University and CSIRO
A new regional groundwater flow and transport model of the Adelaide Plains has been developed. Such a model is viewed as the best tool available to integrate the data as it allows accounting for all spatiotemporal constraints implied by the regional setting. The model domain extends from the major faults at the foothill of the Mount Lofty Ranges (MLR) in the south and south-east, up to 5 km offshore in the west and it is bounded by the Light River in the north. Compared to previous modelling efforts for the same area, the new platform includes the following key improvements:
- The implementation of boundary conditions relies on a stronger physical basis.
- The hydrostratigraphy was revised according to the newest interpretation of geological data.
- A sensitivity analysis was performed on grid resolution, time-step resolution and initial condition for the transient flow model and used as a guide to decide on these structural parameters.
- A larger dataset for calibration was collated.
- Automatic calibration (as opposed to manual calibration) was achieved; however, while the initial aim was to use hydraulic head and chemistry data as calibration targets, compatibility issues between MODFLOW-NWT and MT3DMS precluded this and thus only hydraulic head data were used.
- Calibration performance was extensively assessed using relevant indicators.
- Parameters sensitivity, identifiability and uncertainty were analysed.
- The model was built using a script based approach, facilitating modification.