Flood Susceptibility Analysis in West Rapti River Basin Using Frequency Ratio Model

Abstract

Floods are recognized as lethal natural events, which result in devastating natural and human losses. So, identifying flood susceptible zones is crucial to adopt necessary mitigation strategies beforehand. With the advent of GIS tools and modelling techniques, mapping of such zones has become easier and more precise; yet, flood prone countries like Nepal have not been able to embrace such tools for flood risk management. With a compelling need to address this situation, this paper employs Frequency Ratio model to analyze flood susceptibility in the West Rapti River Basin. The model, created with the help of 77 flood points and tested with 30 points to obtain 80.7% accuracy, maps the flood hazard zones in the area and identifies the lower Terai and settlement regions as high-risk areas. With the increasing threat of changing climate in the future, this study also propounds better preparation of flood inventory maps in the future for more precise susceptibility analysis models and better flood risk management.

Evolution and future prospects of hydropower sector in Nepal: A review

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GIS and Remote Sensing Based Assessment of West Rapti River Channel Migration in Nepal

“…Stretching from Nepal's Mahabharat Range to the Chure Range, the West Rapti River (WRR) is an important watercourse that supplies water for agriculture and other purposes in the area [51,68]. It has been identi ed as highly prone to oods over settlements proximity to 500 m from riverbanks [10], and soil erosion, resulting in severe losses to lives and property within local communities [27]. According to the 2019 Climate Change and Disaster Risk and Vulnerability Context Report for Province 5, certain areas face different major hazards.…”

Climate Change and Flood Vulnerability Analysis in the Narayani River of Nepal

“…Nepal, in particular, faces devastating floods annually, accounting for a significant portion of both human casualties and property damage (Bhattarai & Ghimire, 2023;Gautam et al, 2016). Historical flood occurrences in Nepal have shown that the most significant losses occur along river and rivulet channels, with devastating flood events, for instance, in the years 1993, 2002in central Nepal, 2008in the Koshi River, 2008in western Nepal, 2012 in the Seti River, and 2017 all over the country highlighting the vulnerabilities along riverbanks (Shrestha et al, 2020).…”