the detrimental effects of swirling motion such as flow reduction, vibrations, loss in efficiencies of pumps and turbines and of structural damage, prompt engineers to design intake structures to avoid swirling motion , which results in vortices. This paper carries out laboratory experiments at the Hydraulics Laboratory, Faculty of Engineering, Cairo University, to study the rate of discharged sand through vertical drain pipes due to the scouring effects accompanying the vortex formation, which may result in machine deterioration. Results suggested by analysis have been determined experimentally and plotted as a set of curves that may be useful in engineering design.