Geospatial delineation of flood susceptible zones using analytical hierarchy process

Abstract

Demarcation of flood-prone areas based on risk level plays a key role in flood management systems. Geospatial approach has gained much significance among the researcher working in flood risk management. This work incorporated an analytic hierarchy process (AHP) and geographic information system (GIS) to delineate the flood susceptible zones of the lower Damodar River basin. Various influencing factors were initially assigned with weights with respect to their relative importance towards flood susceptibility and integrated into GIS platform by weighted overlay approach. Based on the current study area, the flood zone map was sub-classified into four zones, namely critical, high and low, and safe zone, respectively. Moreover, sensitivity analysis was also performed to evaluate the most significant factors in flood susceptibility using the exclusion of factors from the estimation of flood zone index. Sensitivity analysis showed that River distance and elevation are the most sensitive factors for evaluating flood zonation.