Flood risk assessment of suburban region in India by incorporating flood hazard, vulnerability and exposure

Flood risk mapping is essential for improving disaster management and preparedness, typically evaluated as the combination of flood hazards and potential consequences determined by vulnerability and exposure assessments. This study introduces a comprehensive flood risk assessment (FRA) framework designed for dense suburban areas by integrating flood hazard, topography, socio-economic vulnerability, and exposure. Exposure is evaluated through housing conditions and damage classification across various land use categories. Municipal-level FRA presents challenges due to the spatial resolution of socio-economic data and infrastructure indicators, particularly in urban and suburban areas where overlapping zones and housing communities complicate assessment. The framework is applied to Kulgaon–Badlapur Municipal Council (KBMC), located along the Ulhas River in Maharashtra, India, which faces increasing flood risks due to the rise in short duration high intense rainfall and receives annual rainfall over 2000 mm. Results indicate that flood risk is concentrated in densely populated wards near the river, with some low-density areas highly vulnerable due to unfavourable topography. The increase in real estate developments further exacerbates vulnerability and overall risk. Notably, a significant portion of Valavli and Manjarli wards are at high risk, while parts of the industrial zone are also vulnerable due to their proximity to the river. The generated flood risk map is validated through ground observations and aerial imagery, and the study found that the proposed FRA framework offers a practical and realistic flood risk evaluation for growing urban and industrial areas. The proposed framework enhances flood risk mapping, and it can provide valuable insights for disaster preparedness, resource allocation, and mitigation strategies, thus making it adaptable for other regions.