Flood hazard and risk mapping for an urban municipality, supporting climate adaptation planning and building code revision.
A detailed urban flood risk assessment for a coastal municipality with a population of approximately 85,000. The project delivered flood hazard maps for three return periods, a risk assessment covering exposed assets and population, and an adaptation options appraisal to guide the municipal climate action plan.
A 2D hydrodynamic model was built using high-resolution LiDAR terrain data, calibrated against historical flood records from three major events. The model simulates both pluvial (rainfall) and fluvial (river overflow) flooding.
Flood hazard maps were combined with exposure data (buildings, infrastructure, population) and vulnerability functions to produce risk estimates expressed in annual average damage (AAD) across the study area.
Based on the risk assessment, a set of structural and non-structural adaptation measures were evaluated using a cost-benefit framework. Recommended measures included upstream retention, improved drainage capacity and revised building setback requirements.