Surface water and groundwater interaction is an intrinsic component of the hydrologic budget on the watershed. Hydrologic modeling tools must account for this interaction to provide reliable predictions.In this study, for the simulation of the groundwater system, a steady and transient state groundwater model has been developed using the Visual MODFLOW program for a study area of Aa river, which is located on the eastern part of the Nete area, NE of Antwerp, Belgium. ArcView GIS was used for the estimation of the spatially distributed recharge, landuse and soil characteristics of the study area. This combined approach proves an effective tool in characterizing the groundwater-surface water system. This paper describes an analysis of sources of water to a pumping well in a shallow aquifer that discharges to a river.It is evident from the present model study that the groundwater is in direct contact with the river and river gets flow from aquifer throughout the study period. Furthermore, the results of the model are used to analyze the relationship between the groundwater and surface water with spatial extent of perturbations imposed on the entire flow system.