飞来峡库区临时蓄滞洪区洪水风险分析

Analysis of Flood Risk in Temporary Flood Storage and Detention area of Feilaixia Reservoir Area

以飞来峡水库为研究对象,构建了一维、二维以及水力学耦合模型,研究不同年型与频率洪水对临时蓄滞洪区淹没的影响。采用“62·8”和“82·5”两场年型洪水率定模型参数,利用2006年7月和2008年6月两场历史洪水实测资料进行模型验证。经率定与验证,模型成果合理可行。以北江流域发生的两场典型洪水“62·8”和“82·5”设计重现期为300年、200年、100年和50年共8种不同工况,统计其沿程典型断面最高水位、蓄滞洪区淹没面积及洪峰抵达时间,并基于DOM及DEM叠加图统计的库区人口与房屋调查数据,分析4处临时蓄滞洪区的淹没风险。结果表明,飞来峡水库在防御50年一遇以上洪水时,库区临时蓄滞洪区将遭受不同程度淹没影响,亟待加强工程措施与非工程措施以减轻洪水灾害风险。

This paper takes Felaixia Reservoir as the research object.In order to study the impact of different flood types and frequencies on inundation of temporary storage and detention area,one dimensional,two dimensional and hydraulics coupling models were constructed.The model parameters were calibrated by using two annual floods of“62·8”and“82·5”,and the measured data of two historical floods in July 2006 and June 2008 were used to verify the model.After calibration and verification,a total of eight different working conditions were de‐signed based on two typical floods of“62·8”and“82·5”,which were 300,200,100,50 years in recurrence interval.The highest water level of typical sections along the river,inundated area of flood storage and detention area and the arrival time of the flood peak were counted.The population and housing survey data on DOM and DEM superimposed graph were used to analyze the submergence risk of four temporary and detention areas.The results show that the temporary flood storage and detention area will suffer different degrees of inundation,when the Feilaixia reservoir is defending against a flood in more than 50 years.Therefore,it is urgent to strengthen engineering and non-engineering measures to reduce flood disaster risk.