Quantifying the flood risk index of the Malaysian "rice bowl"

Study focus: This study proposed a novel method to estimate the flood susceptibility index based on topographical conditions using Multi Criteria Decision Making approach with a specific hazard classification, to determine the paddy flood vulnerability index considering all paddy growth periods and to establish risk classification by integrating flood inundation and damage, as risk is a combination of probability and impact of an event to occur. New hydrological insights: Flood occurrences at paddy fields are not uncommon and pose a serious threat, because rice is a staple food for most Asian countries. In a tropical environment, paddy cultivation normally undergoes three growth stages, namely vegetation, reproductive and ripening. These stages have different water requirements. Therefore, it is essential to include the paddy growth stages in the risk assessment, as well as the inundated duration and depth which are unique to the specific location and the paddy seed variety. These parameters have not been investigated in previous studies. The risk indices were classified into 5 major classes, namely very low, low, moderate, high and very high. A comprehensive flood risk map developed in this study can be used by all relevant authorities and stake holders to evaluate the level of flood risk.