Risk Analysis of Flood Forecast and Pre-Discharge Operation of Reservoir

Flood forecast and pre-discharge operation is one of the most important flood control methods,which can im-prove flood control ability of reserviors.We defined pre-discharge operation risk through analyzing the possible results of pre-discharge operation with flood forecasting.Incoming runoff random simulation method was established considering flood forecasting error.The method was applied in Wangkuai reservoir and Longmen reservoir in Daqing river basin.Results show that it is very possible that flood control level cannot be restored in time and water supply will be affected for 10-year return flood;while flood pre-discharge operation can improve benefit of flood control obviously for 20-year return flood.