Flood susceptible surface detection using geospatial multi-criteria framework for management practices

Nowadays, preparing natural hazard maps has become essential to protect society and its infrastructure from future natural disasters. In this context, the multi-criteria semi-quantitative technique, the analytical hierarchy process (AHP) was integrated into the Geographic Information System (GIS) environment to produce a flood hazard map. The Lower Mahananda basin of India was chosen as the study area that annually suffers from damage from floods. The produced map was categorized into five classes as the zones of flood susceptibility, namely very high, high, moderate, low and very low. The corresponded zones were then examined using sensitivity analysis, and the results show there are very small differences in the spatial distribution of flood susceptible zones. The high flood hazard zones (18%) are located generally along river tracts in the lower portion of the study area that gets flooded more or less every year. The comparison found between the various flood susceptible zones, and the rise in the water level at the Mahananda conveys the accuracy and reliability of the applied methodology. Moreover, the settlement zones were identified within the high flood probable category and the sub-districts situated along the western margin have been found with inadequate medical facilities to combat the flood events. Therefore, the proposed methodology and resultant analysis of the work can be useful for local government authorities to prepare flood mitigation plans and strategies.