Flood risk in cities and built-up areas is a major threat which is likely to grow due to increased urbanisation and climate change. It is a priority for urban planning, civil defence and insurance to accurately represent buildings and urban features in hydrodynamic models to assess flood risk to people, properties, assets and infrastructure in an uncertain future. The correct representation of urban features in models is currently blocked by the lack of detailed and accurate techniques and has become a priority for the improvement of urban flood modelling now that better data and computational resources are available. This study has reviewed the available approaches for the representation of buildings and urban features and implemented the widely used ‘stubby building’ approximation as well as a more realistic and innovative ‘building hole’ approach using the hydrodynamic model CityCAT. The city centre of Newcastle upon Tyne, UK, was used as a case study, allowing independent validation of the methods and direct, systematic comparison of performance. Shortcomings of the approximate method are described, and guidance given on limits to its reliable application and scope for improvement.

中文翻译：

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在水动力洪水模型中代表建筑物和城市特征

城市和建成区的洪水风险是一个主要威胁，由于城市化进程加快和气候变化，这种威胁可能会加剧。城市规划、民防和保险的首要任务是在水动力模型中准确地表示建筑物和城市特征，以评估不确定的未来对人员、财产、资产和基础设施造成的洪水风险。目前，由于缺乏详细和准确的技术，模型中城市特征的正确表示受到阻碍，并且由于可以获得更好的数据和计算资源，因此已成为改进城市洪水建模的优先事项。本研究回顾了表示建筑物和城市特征的可用方法，并实施了广泛使用的“粗短建筑”近似法以及使用流体动力学模型 CityCAT 的更现实和创新的“建筑洞”方法。英国泰恩河畔纽卡斯尔市中心被用作案例研究，允许对方法进行独立验证并对性能进行直接、系统的比较。描述了近似方法的缺点，并就其可靠应用的限制和改进范围给出了指导。