Assessing Flood Vulnerability in Ho Chi Minh City

Background and objective: Urban flooding has become a critical challenge in Ho Chi Minh City (HCMC) under rapid urbanization and climate change. However, integrated assessments combining physical and socio-economic vulnerability remain limited. This study aims to assess urban flood vulnerability in HCMC by developing a localized Flood Vulnerability Index (FVI) to support vulnerability-based adaptation and policy prioritization.Methods: The assessment adopts the IPCC vulnerability framework, defining vulnerability as a function of exposure (E), sensitivity (S), and adaptive capacity (AC). A multi-method approach integrates Geographic Information Systems (GIS), remote sensing indices (MNDWI and NDVI), and the Analytical Hierarchy Process (AHP) to weight indicators based on expert judgment. A quantitative household survey of 40 households conducted in June 2025 was used to assess socio-economic flood impacts.Results: Approximately 80.2% of HCMC’s area exhibits moderate to very high flood vulnerability. High-vulnerability hotspots are concentrated in low-lying southern and southwestern districts, notably Thạnh An, Cần Giờ, Hiệp Phước, An Thới Đông, and Nhà Bè, where tidal E overlaps with limited drainage infrastructure. The central urban core shows lower vulnerability due to higher AC. Survey results indicate frequent inundation affecting 55.3% of households, with average flood-related damages of about 2,200 USD per household.Conclusion: Urban flooding in HCMC is a socio-spatial issue driven by uneven development and climate change, underscoring the need for vulnerability-based flood risk management integrating adaptive land-use planning, infrastructure investment, and community resilience.