INCREASING THE ECONOMIC BENEFITS OF TAIHE RESERVOIR BY MEANS OF OVERTOPPING RISK ANALYSIS

摘要

Overtopping risk analysis against simultaneous actions of flood and effective wind series was applied to the management of water resources for a large reservoir―Taihe Reservoir located in Shandong Province, China. The maximum storage capacity of the reservoir is 1.833 X 10~8 m~3. It has an earth dam. In the analysis, the flood, wind, volume of reservoir and discharge capacity are all considered as random variables. Then a stochastic differential equation and a risk model are established for the earth dam to analyze its risk of overtopping against the design series of flood events accompanied with the runup generated by wind wave during flood period. On the basis of risk analysis, it was recommended that its limiting reservoir level before coming flood originally suggested by Taihe Reservoir Administration, say 226.0 m may be raised to an elevation of 230.5 m much more on the safe side which corresponds to a risk of the order of 10~(-8)(or a safety of 99.99999%) against overtopping under concurrence of flood and wind events during flood period. The increase of volume of storage corresponding to the suggested increment of limiting level, 4.5 m, will be 2.511 X 10~8 m~3, which may bring a remarkable economic benefit to Taihe Reservoir Administration.