Development of a novel flood control chart at ertan reservoir

Ertan reservoir is a large scale reservoir with the electricity generation as its main purpose.As a single functioning reservoir,it was not designed to provide flood alleviation functions to downstream areas.Since there is no designated flood storage,the spillage during the flood seasons is common and it was difficult to provide any flood control operations.This paper describes a novel flood control chart based at Ertan reservoir.Depending on the inflow,flood storage can be calculated and provided in the reservoir by the chart.This chart can not only solve the conflicting demands of electricity generation and the flood control of the reservoir,but also be able to cut and shift flood peaks to avoid the coincidence with the flood peaks in downstream river such as Jinsha river and Yangtze river.It provides a useful guidance for the closure of the sluice gates to restore the full pool in the reservoir by the end of the flood season.This chart can be used as real time operation rule curves for flood control,electricity generation and water level control during the flood season.The application of the chart has shown that it is very flexible and has a huge potential to be applied to other large scale reservoirs which are used for electricity generation or whose inflow patterns are quite regular.