2013年丹江口大坝加高工程完成后,遭遇连续枯水,各年度蓄水严重不足,2017年发生明显秋汛,防汛部门科学调度,取得了统筹防洪、大坝蓄水安全与监测试验等多目标共赢的成果.通过分析汉江2017年秋汛的水雨情发展、洪水地区组成、水情预报及水库调度等,解析了汉江此次秋汛过程的降雨、洪水特性,水情预报精度水平及水库调度的成效.分析表明:汉江9月上中旬降雨起筑底作用,9月23日开始的连续强降雨过程累计雨量大、覆盖面积广,直接导致汉江连续涨水过程;丹江口入库洪水最大15 d洪量接近秋季10 a一遇,丹皇区间最大7d 洪量超过秋季20 a一遇;丹江口水库实施拦洪削峰调度,削峰率均在50%以上,削减中游干流主要站洪峰水位约2m,避免了中下游分洪民垸和杜家台分洪.%After the completion of Danjiangkou reservoir dam heightening project in 2013,the reservoir suffered a continuous low water,and the annual water storage was seriously deficient.In the autumn 2017,there occurred an obvious seasonal flood, with the scientific operation,the flood control department achieved a multi -objective win -win results in the aspects of flood control,and dam safety monitoring test.Through the analysis of the rain and flood process development, flood region composi-tion,hydrological forecasting of 2017 autumnal flood,this paper summarizes the rainfall process,flood characteristics,flood fore-cast accuracy and the achievements of reservoir operation.The results show that the rainfall in the Hanjiang River Basin in mid -September formed the foundation of the flood,since 23rd Sept.,the subsequent heavy rainfall with a large accumulated rainfall and coverage directly caused the flooding process of the Hanjiang River;the max.15d flood volume into Danjiangkou Reservoir closed to 10 years frequency of autumnal flood,the max.7d flood volume of the Dan-Huang interval area was over 20 years fre-quency of autumnal flood.The reservoir implemented an operation way of flood detention and peak reduction,by which,the peak-reduced rate was more than 50%with the flood peak water level reduced in about 2 m at the lower reaches′stations of the reser-voir,and the operation of flood diversion polders and Dujiatai flood detention zone in the mid -low reach were avoided.
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