Flood Exposure and Social Vulnerability during 2020 Assam Floods

Abstract

The state of Assam, primarily in the Brahmaputra basin, is one of the most flood-prone states of India, with devastating floods occurring every year. Rapid urbanization in the floodplains and inadequate water management have further exacerbated the human and infrastructural exposure to floods. Despite efforts in organizing relief camps and setting up safe houses, flood losses in terms of life and property have increased. This study presents a novel dataset and an approach that uses a combination of satellite and ground-based data to assess the population’s vulnerability to these floods. The Sentinel-1 SAR data and India Meteorological Department (IMD) rainfall data are used to determine areas in Assam that suffered from floods during July 2020. Additional datasets employed include the population density maps obtained from Facebook, road density maps from the Global Roads Inventory Project (GRIP), relief camp data from the state government, and infrastructure data from a new national dataset sourced from the Pradhan Mantri Gram Sadak Yojna (PMGSY). These geo-tagged datasets are utilized to develop a vulnerability map that would help the policymakers identify vulnerable regions and accordingly strategize infrastructure and disaster preparedness for floods.