The use of groundwater flow models is prevalent in the field of hydrogeology to predict the effects of the external stresses exerted on aquifer system for risk evaluation purposes. In this paper, the authors develop a groundwater flow model in Atbara basin, southeast of Atbara town by using Visual MODFLOW. The purpose of this paper is to investigate the aquifer potentiality with emphasize on groundwater flow and head distribution as well as zone budget using suitable modeling techniques. Hydrological parameters have been calibrated based on the available data observed. The model calibration criteria such as absolute residual mean (ARM), root mean square error (RMS), normalized (RMS) error and mass balance discrepancy of water into and out of the system were adjusted to produced good fit between observed and calculated hydrogeological parameters. Accordingly the calibration is more acceptable with absolute residual mean(ARM) of 0.085m, root mean square error (RMS) of 0.116m, normalized (RMS) error of 1.516% and mass balance discrepancy of 0.05%. The groundwater level decreases from the western side (River Nile) and Eastern side (Atbara River) towards the center of the study area, indicating potential contribution of both rivers in recharging the groundwater aquifers. The calibrated results show that the computed water heads reflect good fit with the measured data, which indicate that the conceptual model and the parameters used in the model can reflect the actual physical system of the study domain. Hence, the model can be applied further to predict the changes of groundwater levels and mass balance under different exploitation scenarios considering the future water demands in the study area.

Numerical Model, Groundwater, Simulation, Atbara Basin