This report covers the testing program undertaken in designing pump sump for Taman Chai Leng Flood Mitigation in Seberang Perai Tengah, Penang. The operations of four pumps on the 1/10^th scale physical model for the proposed pumping station were tested in Hydrology/Hydraulics Laboratory at Universiti Sains Malaysia, Perak Branch Campus, Seri Iskandar.

The purposes of hydraulic model test are to identify:

• Surfaces vortices that may draw air from free surfaces into the pump, causing unbalanced loading of the  impeller, periodic vibrator and reduction in pump capacity.

• Subsurface vortices, which may emanate from the floor, side or back walls, or both, entering the pump, causing vibration and cavitation.

• Pre-rotation of flow entering the pump which will change the attached angle of the impeller blades from the design value and may affect pump efficiency and cause cavitation.

• An uneven distribution of flow at the pump throat which may cause vibration and cavitation.

• Separation of flow from the pump suction bell surface extending to the throat which may cause a non-uniform flow field at the impeller and also the possibility of cavitation.