Model code and solver

MODFLOW-NWT (Niswonger et al., 2011), a Newton formulation of MODFLOW-2005, was chosen to execute the model in order to avoid numerical instabilities associated with cell drying and rewetting in the uppermost layer of the model. The model area is characterised by high-relief topography that usually results in cell drying and rewetting in the unconfined parts of a groundwater model that may cause converging issues. MODFLOW-NWT was intended to solve drying and rewetting problems more efficiently and provide a more stable solution than MODFLOW-2005 by treating nonlinearities of cell drying and rewetting as a continuous function of groundwater head (Niswonger et al., 2011). The GMRES matrix solver was used for solving the linear equations generated by the groundwater model.

Last updated:
11 July 2017
Thumbnail images of the Clarence-Moreton bioregion

Product Finalisation date

20 October 2016