The global increase in urban flooding presents a substantial challenge that affects communities across the globe. This study introduces a post-flood inundation modeling framework tailored to pluvial floods on a metropolitan scale. We employ a dual drainage modeling approach for enhanced accuracy. The framework comprises two primary components: a Storm Water Management Model (SWMM) for simulating water movement within the storm drain system, and an advanced DEM-based flood inundation module that leverages SWMM results to predict flood inundation areas. Compared to the conventional flood spreading models commonly used in dual drainage modeling, this module incorporates high-resolution DEM cells into the surface flow routing processes, allowing to capture intricate surface terrain complexities. Additionally, the proposed module considers direct rainfall impacts on pluvial flood inundation mapping, resulting in enhanced accuracy. To evaluate the proposed model's accuracy, a two-step validation approach has been implemented. This includes comparing the proposed model results with both the high water marks measured in the aftermath of Hurricane Harvey and the flood depth map generated by a hydrodynamic model. The findings affirm the effectiveness of our proposed framework for post-flood inundation mapping within metropolitan settings. This method provides a dependable approach to urban flood modeling and represents an advancement in addressing the challenges associated with urban flooding.

中文翻译：

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基于 DEM 的大都市尺度雨洪淹没建模


全球城市洪水的增加构成了影响全球社区的重大挑战。本研究介绍了针对大都市规模的雨洪量身定制的洪水后淹没建模框架。我们采用双排水建模方法来提高准确性。该框架由两个主要组成部分组成：雨水管理模型 (SWMM)，用于模拟雨水排水系统内的水运动；以及先进的基于 DEM 的洪水淹没模块，利用 SWMM 结果来预测洪水淹没区域。与双排水建模中常用的传统洪水扩散模型相比，该模块将高分辨率 DEM 单元纳入地表水流演算过程，从而能够捕获复杂的地表地形复杂性。此外，所提出的模块考虑了降雨对洪水淹没绘图的直接影响，从而提高了准确性。为了评估所提出模型的准确性，实施了两步验证方法。这包括将提出的模型结果与飓风哈维后测量的高水位线以及水动力模型生成的洪水深度图进行比较。研究结果证实了我们提出的大都市地区洪水后淹没测绘框架的有效性。该方法为城市洪水建模提供了可靠的方法，代表了解决城市洪水相关挑战的进步。