Flood Mapping of the Core Urban Area of Can Tho City Using Hydraulic Modeling

This study investigates the current flood status in the core urban area of Can Tho City, located in the Mekong Delta (Vietnam), through the application of integrated one-dimensional (1D) and two-dimensional (2D) hydraulic modeling. Utilizing detailed topographic data derived from LiDAR, alongside hydrological and hydraulic data including precipitation, land use, and drainage infrastructure. The research developed a comprehensive model to simulate flood inundation under various scenarios. The 1D MIKE 11 HD model was employed for the Mekong Delta region and provided boundary conditions for the more detailed 2D model of the Can Tho urban core. The 2D model, incorporated the city’s flood protection system, was calibrated and validated using historical flood data including the significant 2018 flood event. The validated model was then used to simulate flood scenarios with recurrence intervals of 5, 20, 50, and 100 years, resulting in detailed flood inundation maps. The findings provide one of the first assessments of residual flood risk following the 2023 operational launch of the Can Tho Tide Wall System. Results demonstrate that while the system mitigates tidal flooding in the protected core, significant areas, particularly in the North-West, remain highly vulnerable to deep inundation (>1.0 m) during extreme events. The study provides spatially explicit data crucial for prioritizing secondary flood defense investments and revising land-use zoning in newly identified high-risk zones.