Author(s): M. E. Stevenson; D. A. Reynolds
Linked Author(s): Margaret Stevenson
Keywords: Surface-groundwater interaction; FEFLOW; Land use; Climate change
Abstract: A groundwater flow model of the Lake Warden Wetlands System was developed in order to aid with land use management practices near Esperance, Western Australia. Esperance has experienced recent flooding that is thought to be attributable to land use changes in the upper region of the watershed and climate change; the climate has become drier, with more intense rainfall events. Clearing of scrub and grassland over the last 40 years for farming has increased both the runoff and the recharge in the catchment and decreased the capacity of the land to handle flooding events. The genesis of the flooding in Esperance is shown to be mainly due to surface water; however, groundwater may also be an important component. Due to the high water table in the area during the wet winter season, groundwater contributes to the surface water flow. This project was a precursor to using an engineering approach to partially drain the wetlands and lower the lake water levels. The surface-groundwater interaction was modelled using FEFLOW groundwater modelling software with high conductivity elements to simulate lakes partially fed by groundwater. The model was capable of simulating groundwater levels, but not the lake water levels. Therefore, it was recommended that other methods be considered to model the surface-groundwater interaction. Developments in surface-groundwater interaction modelling will be discussed.
Year: 2009