2016年长江第1号洪水预报及调度影响分析

通过分析2016长江第1号洪水的水雨情发展、洪水组成、水情预报、调度还原计算成果等，解析了该场洪水的暴雨洪水特性、预报对调度的支撑作用以及三峡水库调度对城陵矶河段水位的影响。分析表明：金沙江、乌江来水对第1号洪水起筑底作用，三峡区间洪水则为该场洪水造峰，三者最大1d洪量占三峡入库来水比率分别达26.1%，15.6%，38.1%；第1号洪水期间，水情预报为调度决策提供了长预见期、较高精度的前提支撑，78，54，30，6 h预见期的三峡入库洪峰预报误差分别仅为-20.0%，-10.0%，-4.0%，0；三峡水库在第1号洪水期间通过防洪调度将入库洪峰流量削峰38%，最大拦蓄洪量约29亿m3，削减莲花塘站洪峰水位0.39 m左右，避免了城陵矶河段出现超保证水位。

Regulation effects of Three Gorges Reservoir and flood forecast for No.1 flood in 2016 of Changjiang River

By analyzing the development of rainfall and flood situation, the composition of runoff, and flood forecast and effects of reservoirs operation for No.1 flood in 2016 of Yangtze River, we studied several issues, i.e. the flow and rainstorm characteristics of this flood, support effect of forecast on dispatching, the influence of Three Gorges Reservoir operation on water level of Chenglingji reach. For the No.1 flood, the runoff from the Jinsha and Wujiang Rivers was the fundamentally part, while the peak flow was formed by the local runoff generated in the Three Gorges region. For the maximum 1-day runoff to the TGR, the 26.1%, 15.6%, 38.1% were from Jinsha River, Wujiang River, and the Three Gorges region respectively. And the forecast error of peak flow entering TGR of leading time of 78h, 54h, 30h, 6h were -20.0%, -10.0%, -4.0%, 0.0%, which showed that the flood forecast with long-term prediction and high accuracy provided precondition and support for flood dispatching. With these forecast, the TGR reduced 38% of the maximum discharge and detained 2.9 billion m3 of flood water, which decreased 0.39m of peak level at Lianhuatang Station and successfully avoided exceeding the guaranteed level in Chenglingji Reach.