Flash Flood Assessment in Hilly Regions

According to the ‘Vulnerability Atlas of India’ by the Building Materials and Technology Promotion Council, Uttarakhand is one of the highest flood-prone hilly states. Nainital, Udham Singh Nagar, and Haridwar are the three main districts prone to flood. Also, the National Institute of Disaster Management Report on Uttarakhand’s disaster in 2013 mentions that Nainital and Udham Singh Nagar districts witnessed major flash floods several times. The flash floods of 2010 caused loss and damage, resulting in many people dying and many injured. Floods can also result in secondary events like landslides. To mitigate or adapt to the risk of flash floods, it is essential first to do an assessment. GIS applications enable us to do the same by studying various parameters. Distance from the river, drainage density, bifurcation ratio, slope, elevation, relative relief, rainfall, land use and land cover, and soil are some parameters for flash flood risk assessment (Tariq et al., Water 14: 3069, 2022; Bahadurzai and Shrestha, Flash Flood Risk Assessment for Afghanistan, 2009). The data collected from different sources can finally be collaborated and processed on GIS to analyse and find the district’s most hazard-prone tehsils or areas.