Author(s): Bhadra Devadas; Soumendra Nath Kuiry

Linked Author(s):

Keywords: Flood inundation; Local-inertial model; IROMS; Kerala flood; Flood risk assessment

Abstract: Floods are among the most frequent and devastating natural disasters, significantly impacting lives, infrastructure, and the economy. In recent years, the state of Kerala, India, has experienced catastrophic floods, emphasizing the need for accurate flood modelling tools to support mitigation strategies. This study employs an indigenous two-dimensional (2D) local-inertial hydrodynamic model (IROMS – Integrated River and Ocean Modeling System) to simulate flood inundation in Kerala, leveraging its computational efficiency over full dynamic 2D models and ability to capture the dynamics of flood propagation. The model is applied to the Pamba River Basin, a flood-prone area in Kerala, using high-resolution topographic data and hydrological inputs from rainfall and discharge records. The results are validated using observed flood extents and post-flood surveyed water levels from recent flood events. Key metrics such as the Nash-Sutcliffe efficiency (NSE), Root Mean Square Error (RMSE) and coefficient of determination (R2) are used to evaluate the model's performance. The findings demonstrate that the IROMS accurately reproduces observed flood patterns while maintaining computational efficiency, making it a valuable tool for flood risk management in regions with complex hydrodynamics and resource constraints. The model will be helpful in operational flood forecasting and decision-making processes, contributing to enhanced disaster preparedness and resilience

DOI: https://doi.org/10.64697/978-90-835589-7-4_41WC-P2095-cd

Year: 2025