ASSESSMENT OF FLOOD INFLUENCE CRITERIA IN THE LAM RIVER BASIN USING A COMBINED DELPHI-AHP METHOD

Flood is represented as one of the most destructive natural hazards to humankind. Assessing and predicting floods hazard is necessary to offer appropriate solutions for flood mitigation and sustainable environmental management. It is only possible when the main criteria that contributed to creating the flood hazard are pointed out. The purpose of the current research was to choose and attribute scores to all various flood-causing factors in the Lam river basin. Firstly, the Delphi method was applied to the expertbased survey to choose six key parameters that led to the floods, including rainfall, slope, relative slope length, drainage density, land cover, and soil. Then, Analytic Hierarchy Process (AHP) approach is employed as an effective tool to obtain a better understanding of all the factors or indicator contributions in the flood process based on weight given to each of six flood influencing elements. The consistency analyses revealed that the findings were coherent and consistent with a previous study. It is also interesting to notice that rainfall and slope are the most prominent flood occurrence criteria with 45% and 25.5%, respectively. However, the influence of other factors (drainage density, relative slope length, land cover, and soil) is not visible. These parameters are assigned to the small weights and do not have a significant influence on the flood phenomenon. The study results provide baseline information, which needs to be taken into account to mitigate and control floods.