Coastal Flooding Vulnerability Mapping in Calabar Metropolis, Cross River State

Coastal flooding is an escalating hazard in Nigerian coastal cities, driven by sea level rise, storm surges, and inadequate urban drainage infrastructure. This study develops a coastal flooding vulnerability map for Calabar Metropolis, Cross River State, South South Nigeria, integrating physical exposure, socioeconomic sensitivity, and adaptive capacity indicators within a geographic information system framework. Topographic data from shuttle radar topography mission digital elevation models (resampled to five-metre resolution) and LiDAR-derived terrain models are used to delineate flood-prone zones under 0.5-metre, one-metre, and two-metre sea level rise scenarios. Historical flood extent data from 2020, 2022, and 2024 flood events are incorporated for validation. Socioeconomic vulnerability is assessed through household surveys administered to 350 respondents in eight flood-risk wards, capturing indicators of income, housing quality, health status, and awareness of flood early warning systems. Institutional adaptive capacity is evaluated by reviewing existing flood management plans, early warning infrastructure, and government response capacity. A composite vulnerability index is computed by aggregating and weighting physical, social, and institutional indicators using the analytical hierarchy process. Findings are expected to identify Akpabuyo and Creek Town neighbourhoods as areas of highest combined vulnerability. Recommendations include targeted flood defence investment, community resilience training, and the upgrading of the Calabar drainage master plan. Keywords: coastal flooding, vulnerability mapping, Calabar, sea level rise, flood risk assessment