Efficiency exploration of frequency ratio, entropy and weights of evidence-information value models in flood vulnerabilityassessment: a study of raiganj subdivision, Eastern India

The primary objective of this research was to assess the efficiency of RS and GIS for predicting the flood risk in Raiganj Sub-division, Eastern India using the Frequency ratio, Entropy index, and Weight of evidence-information Value models. Consequently, for spatial analyses fourteen flood conditioning variables are constructed. The research region is experiencing floods consequently in the past with moderate to high intensities. The assessment demonstrates that factors such as elevation, LULC, rainfall, distance from rivers, and drainage density contributed significantly to the occurrence of floods. From the estimation, it is found that about 11.02 per cent (Frequency Ratio result), 13.90 per cent (Entropy’s result), and 11.50 per cent (WofE-IV results) of the total area has very high vulnerability status respectively. Around 33 per cent to 47 per cent of the total area of each block in the subdivision is projected to be in danger of floods. The validation of the results indicates that the success rate of the presently constructed maps was 0.933 for the FR model, 0.917 for the SEI model, and 0.907 for the WofE model indicating that the frequency ratio model for mapping flood risk in the study region is more authentic, reliable, and useful for delineating flood vulnerable areas and potential flood risk sites. The findings of the analysis will help planners to develop flood prevention measures as part of regional flood risk management programs, as well as provide a foundation for future research in the study area.