A transbasin diversion project is always a large-scale and long route engineering, and meanwhile, there exist many complex geological conditions and large differences in geomorphologic settings and meteorologic conditions along the project route. It is urgently required to cut off the flow or decrease it by a wide margin through gates for accident prevention at a short time so as to control the harm due to a sudden event and adopt corresponding measures when a sudden event caused by a natural disaster, a communication accident or other security event occurs all at once. This article focuses on categorizing the sudden events which probably happen in the normal water supply process of the transbasin diversion project and puts forward relevant emergent water transfer dispatch measures according to four aspects which include the safety of water quality, the security of the open channel and the hydraulic structure, the fault of the equipment and the safety of the society. We propose the objective and principle of emergent dispatching of a sudden event and the train of thought for further research.