Coupled modelling of subsurface water flux for an integrated flood risk management
Coupled modelling of subsurface water flux for an integrated flood risk management
复制标题
用于综合洪水风险管理的地下水通量耦合建模
DOI：
10.5194/nhess-9-1277-2009
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发表时间：
2009
影响因子：
4.6
通讯作者：
K. Ullrich
中科院分区：
文献类型：
--
作者：
T. Sommer;C. Karpf;N. Ettrich;D. Haase;T. Weichel;J.;B. Steckel;K. Eulitz;K. Ullrich
抽象。洪水事件不仅在地表，而且在地下造成重大破坏。地表水渗入土壤、城市下水道系统泛滥以及随之而来的地下水上升是造成地下损害的主要原因。洪水事件模拟是洪水风险评估的重要组成部分。地下排放的渗透水的过程需要耦合建模工具，地表和地下水通量。因此，地面洪水、污水系统排放和地下水流的规范相互结合。耦合软件用于合并不同模型几何之间的映射，时间同步和数据交换方面的各个程序。在萨克森首都德累斯顿（德国）的两个尺度上实现了模型的耦合。作为耦合模拟的结果，它可以表明，表面洪水占主导地位的任何洪水事件的过程。与没有耦合模型的洪水模拟相比，无法确定表面淹没面积的实质性变化。关于下水道，地下水流入下水道与洪水渗透造成的负荷之间的比较表明，地表洪水的渗透是下水道负荷过重的主要原因。同时发生的事件会使问题更加严重。上升的地下水对下水道系统的渗透对下水道系统的负荷只起很小的作用，下水道系统的水分配对地下水上升只产生局部影响。然而，由于地下水上升的风险地区的本地化需要考虑的所有组成部分的地下水通量。耦合模型表明，高地下水位是洪水事件之前和期间发生的多原因过程的结果。
Abstract. Flood events cause significant damage not only on the surface but also underground. Infiltration of surface water into soil, flooding through the urban sewer system and, in consequence, rising groundwater are the main causes of subsurface damage. The modelling of flooding events is an important part of flood risk assessment. The processes of subsurface discharge of infiltrated water necessitate coupled modelling tools of both, surface and subsurface water fluxes. Therefore, codes for surface flooding, for discharge in the sewerage system and for groundwater flow were coupled with each other. A coupling software was used to amalgamate the individual programs in terms of mapping between the different model geometries, time synchronization and data exchange. The coupling of the models was realized on two scales in the Saxon capital of Dresden (Germany). As a result of the coupled modelling it could be shown that surface flooding dominates processes of any flood event. Compared to flood simulations without coupled modelling no substantial changes of the surface inundation area could be determined. Regarding sewerage, the comparison between the influx of groundwater into sewerage and the loading due to infiltration by flood water showed infiltration of surface flood water to be the main reason for sewerage overloading. Concurrent rainfalls can intensify the problem. The infiltration of the sewerage system by rising groundwater contributes only marginally to the loading of the sewerage and the distribution of water by sewerage has only local impacts on groundwater rise. However, the localization of risk areas due to rising groundwater requires the consideration of all components of the subsurface water fluxes. The coupled modelling has shown that high groundwater levels are the result of a multi-causal process that occurs before and during the flood event.