小浪底水库防洪作用分析

根据黄河下游防洪工程体系现状,拟定了小浪底水库投入运行后的干支流水库调洪方式,分析了小浪底水库的防洪作用。结果表明,小浪底水库的兴建使黄河下游大堤的设防标准由现状的六十年一遇提高到千年一遇(即千年不用北金堤);使花园口百年一遇洪峰流量削减到16000m~3/s以下(即百年不用东平湖新湖区);使花园口22000m~3/s以下的较大洪水削减到10000m~3/s以下(即不用东平湖滞洪区);发生万年一遇洪水时,只需用北金堤滞洪区少量分洪即可;将三门峡水库对“下大洪水”的运用机率由十年一遇减少至百年一遇,各种级别洪水的蓄洪量均有较大幅度减少。

Analysis On Flood Prevention Function of the Xiaolangdi Reservoir

According to the present status of flood control engineering system in the lower Yellow River, flood control methods for reservoir on the trunk and tributaries are worked out and the function of flood control of the Xiaolangdi Reservoir is analysed after the Xiaolangdi Reservoir putting into operation. The results show that after building the Xiaolangdi Reservoir, the design standard for flood prevention of levels in the lower Yellow River is increased from the existing 60-year frequenly to 1 000-year frequenly, i. e. the Bei jindi Detention Basin will not be used in 1000 years; 100-year peak discharge at Huayuankou Station will be reduced to 16000m~3/s, i. e. the new area of Dongping Lake Detention Basin will not be used in 100 yesrs; a major flood of below 22000m~3/s at Huayuankou will be cut down to 10000m~3/s i. e. Dongping Lake Detention Basin will not be used; a little amount of water is retarded by Beijindi Detention Basin if there is a 10000-year flood occurred; and the operational opportunity of Sanmenxia Reservoir for major floods occurred in the downstream of Sanmenxia is decreased from 10-year frequenly to 100-year frequenly and the storage capacity for various levels of floods will be reduced greatly.