Increase Spillway Capacity using Labyrinth Weir

Uncertainty in the change of seasons, high-intensity rainfall, floods and droughts in many areas which previously never experienced such disaster, are natural phenomena as a result of climate change. Impact of these phenomena on the reservoir is that water surface rises faster. This situation may endanger the dam. The concept of labyrinth sharp crest spillway (LSCS) has been used in the study to increase capacity without lowering spillway crest. Existing spillway is considered as the Ogee type. Six kinds of LSCS have been used in the research. The experiments were performed in the laboratory by using an open flume. Ogee prototype was made of wood and LSCS was made of acrylic. During the experiment, water was flowed into the flume with varying discharge. At any change of water thickness above spillway, the water discharge was measured. Observation has been done both on the Ogee and LSCS. The experimental results showed that the ability of LSCS in flowing water is greater than Ogee. Water flowed through the LSCS, particularly trapezoid type-1, about 170% more than that of Ogee. Thus, LSCS is considered to be valuable as an alternative spillway in case of dam safety.