Urban Pluvial Flooding Assessment with a Subgrid Approach for the Secondary Drainage Network: An Application in Padova

This study presents a practical application of a subgrid approach for urban pluvial flooding that implicitly accounts for the secondary drainage network. Parameters required by the subgrid model (e.g., pipe diameter, spacing) can be easily estimated, reducing the data requirements and modelling efforts compared to classical 1D/2D simulations. Applied to simulate the 2009 flooding of a Padova district, the model improves accuracy in flood extent and water levels compared to models that ignore the secondary network, without the need for surveys of smaller-scale pipes. This data-efficient approach proves to be a practical tool for simulating urban pluvial floods, particularly in data-scarce urban areas.