Estimation of MFFPI for flood hazards assessment using geospatial technology in the Tawi Basin, India

Abstract

>Flash flood in the Himalayan River has made some catastrophic effects on the life people residing in its river banks mainly associated with extreme rainfall events/cloud bursts/the collapse of moraine-dammed lakes which significantly leads to rapid flooding and subsequently disaster in low laying areas. In the present study, we used different equations to determine the flash flood potential index(FFPI) and further, an improved Modified Flash Flood Potential Index (MFFPI) equation has been used to estimate the area with a predisposition to water accumulation. Various thematic layers prepared in the Geographic Information System (GIS) environment and integrated by providing proper weightage to each thematic layer i.e., slope, profile curvature, soil texture, geology and Land Use Land Cover (LULC), flow accumulation, slope, and profile curvature, etc. The MFFPI equation-derived map of Tawi Basin is classified into five zones such as very high hazard (100.40 km²), high hazard (971.60 km²), medium hazard (92.78 km²), low hazard (634.03 km²) and the very low hazard (254.61 km²) areas. Further, the results of the MFFPI were validated with the Analytical Hierarchy Process (AHP) based flood hazard zonation results which shows a very high correlation and similar trends of spatial and areal distribution with the MFFPI. The results of this study are quite useful for the local administration for futuristic planning and management of flood hazards in the Tawi River Basin and many other basins of similar terrain around the world.