Dam-break analysis with infoworks ıcm model for earthquake-damaged Sultansuyu Dam: Different scenarios and computational costs

Despite the many benefits of dams built for various purposes, their failure remains a serious risk due to the large volumes of water they store. The simulation of dam failure incidents is crucial for both emergency preparedness and risk mitigation strategies. This research conducts a dam-break analysis of the Sultansuyu Dam, which sustained significant damage during the earthquake that struck Türkiye on February 6, 2023, employing a hydrodynamic model formulated with the InfoWorks Integrated Catchment Modelling. Five distinct scenarios were crafted to assess both the computational cost and the dynamics of flooding behavior. There are four scenarios with complete reservoir condition (60 m) and velocity limits of 3, 5, 10, and 15 m/s, and the last one has a water depth of 50 m and a velocity limit of 15 m/s, indicating the depth at the time of the earthquake event. For each, flood inundation, velocity, and hazard maps were generated. Model validation with a historical rainfall event produced satisfactory performance (R² =0.772, NSE =0.467, RMSE =0.136 m). Results show that increasing the velocity limit causes the floodwater to move through narrower cross-sections, reducing overall inundation but increasing local flow depth. About 95% of flooded areas were classified as extreme hazard zones. Computational time increased by 1,219 seconds from the lowest to the highest velocity limit, indicating that lower limits require less computational effort. The study shows how velocity limits in hydrodynamic modeling affect flood hazard and computational efficiency, offering practical insights for dam safety and emergency planning.