ANNUAL CONGRESS 2025

An Assessment Framework for Evaluating Urban Flood Vulnerabilities Using Night-Time Light Data

Not scheduled

20m

Yildiz Technical University, Istanbul

Oral Track 12 | DISASTER-RESILIENT PLANNING

Speaker

Ms Nuwani Kangana (Consultant-Office of Research, University of Moratuwa, Sri Lanka)

Description

Urban flooding, responsible for 44% of all natural disasters worldwide from 2000 to 2019, impacts more than 2 billion people each year. This study presents a unique methodology for evaluating urban flood vulnerability in response to the growing challenges posed by rapid urbanization and climate change. By integrating flood susceptibility and human exposure, the research introduces a novel framework that utilizes Night-Time Light (NTL) data as a dynamic indicator of human activity and urban density. This approach overcomes the limitations of traditional methods, such as static data or post-flood assessments, by incorporating dynamic and real-time data. It focuses on human exposure to urban flooding, addressing the rapid changes in urban environments and overcoming challenges like sparse data availability and the lack of frequent analysis. By addressing these shortcomings, the methodology offers a comprehensive and scalable solution for assessing urban flood vulnerability in a dynamic and evolving context. This study focuses on the Kelani River watershed in Sri Lanka, which is not only the highest flood-prone watershed in the country but also the most densely populated region in the country, making it a critical area for urban flood vulnerability assessment. The study adopts nine conditioning factors, such as slope, precipitation, and soil type, integrated with NTL data to derive comprehensive vulnerability maps. To make this analysis useful and accessible, a web application is created in Google Earth Engine. This application provides an up-to-date, interactive platform for visualizing urban flood vulnerability that will empower urban planners, policy makers, and disaster risk managers to make informed decisions. The findings underline the transformative potential of NTL data in the quantification of urban flood risks and offer a scalable and cost-effective solution adaptable to diverse urban contexts. The integrated framework not only improves the assessment of urban flood vulnerability but also supports proactive disaster risk reduction and sustainable urban planning, enhancing the resilience of urban areas prone to flooding.