Abstract:
The coastal state of Kerala, India experienced unprecedented levels of rainfall and
flooding in August 2018, resulting in huge life and property loss. Since then the impact
reservoir management may have had on the severity of the 2018 Kerala floods has been in
question. This study presents a novel approach to developing a reservoir model using HEC HMS and HEC-ResSim models, combined with satellite remote sensing data. In order to
establish a link between flood severity and reservoir management, a model of the Kakki
reservoir in southern Kerala was created. Simulations were carried out for six long term, two
short term, and two immediate run cases. It was found that all cases except the immediate
simulation run resulted in a reduced peak flow. The long simulation run, which altered the
guide curve after the heavy rainfall occurring on 14th August 2018, while constraining the
outflow, was found to produce the greatest reduction in peak outflow. The significant peak
outflow reduction achieved suggests that improved reservoir management could have reduced
the severity of the 2018 floods.
