2016 年太湖流域洪灾损失及骨干工程防洪减灾效益评估研究

为了评估 2016 年太湖流域梅雨期间骨干工程发挥的防洪减灾效益，利用流域一维河网水动力学数学模型，计算得到无骨干防洪工程情景下的河段水位过程，将其与河段设计水位比较，推算每个河段两岸的淹没水量。再与 DEM 和圩堤等阻水构筑物数据相结合，通过空间叠加分析和水量平衡计算，获得洪水淹没的空间分布。建立了流域洪灾损失评估模型，基于土地利用数据、洪水淹没分布和社会经济数据，对无骨干防洪工程情景下的洪灾直接经济损失进行了评估。将该损失与调查统计的实况洪灾损失数据进行对比，结果表明: 骨干工程在此次洪灾中发挥了约 116. 12 亿元的防洪减灾效益。其中，无锡市和苏州市防洪减灾效益最大，分别达到了 50. 08 亿元和 44. 11 亿元。研究成果定量论证了太湖流域骨干防洪工程在 2016 年洪灾中的经济效益，采用的评估方法对于其他流域或区域防洪工程效益评价具有一定的参考价值。

Study on flood losses and disaster reduction benefits assessment of key flood control projects in Taihu Basin in 2016

In order to assess disaster reduction benefits of the key flood control projects in Taihu Basin during plum rain period in 2016，by comparing the water level processes in case of no these key projects which are simulated by one-dimensional river network hydraulic model with the design water level of each river reach，the flood inundation volumes on both sides of all the river reaches are calculated． Then，combined with DEM and water barrier structures ( such as polder dike) data，flood inundation distribution is obtained by spatial overlay analysis and water balance calculation． A flood disaster loss assessment model for Taihu Basin is established． Using this model，the direct economic loss in the scenario of no key flood control projects is evaluated based on land use data，flood inundation distribution and social economic data． The comparison results between evaluated economic loss and investigated flood damage data show that the key projects bring obvious flood control and disaster reduction benefits，totally about 11. 612 billion ＲMB． In which Wuxi and Suzhou are the biggest，5. 008 and 4. 411 billion ＲMB respectively． The study quantitatively analyzes enormous economic benefits produced by key flood control projects in Taihu Basin during flood events in 2016 and the assessment method can provide a reference for other basins or regions．