Initial assessments of topographic variability effects on urban pluvial flood modelling accuracy

Pluvial flooding is a growing concern due to climate change and urbanization. Accurate flood modeling requires high-resolution topographic data, but data availability, inconsistencies, and computational constraints pose challenges. This study examines the sensitivity of pluvial flood models to digital terrain model (DEM) resolution using HEC-RAS 2D in a frequently flooded Genoa neighborhood. Simulations with 5m, 1m, and 0.5m resolutions assess flood extent, depth, and computational efficiency. Results highlight the importance of high-resolution data for accurate predictions. The research informs urban flood risk management by balancing data granularity with resource efficiency, advocating for microtopographic integration and DEM-DSM comparisons.