When the Levees Break: Computational Flood Risk Prediction in Tanjay City Using Hazard Exposure and Human Vulnerability Analysis

Arnel Baquero II; Ishq Catingub; Nino Jerard Buquiran

Authors

Arnel J. Baquero II University of the Visayas, Main Campus, Cebu City Author https://orcid.org/0009-0008-1516-1743 (unauthenticated)
Ishq Q. Catingub Author
Nino Jerard T. Buquiran Author

Keywords:

Flood risk assessment; computational modeling; hazard–exposure interaction; rainfall intensity; population density; Tanjay City, Flood risk assessment, computational modeling, hazard–exposure interaction, rainfall intensity, population density, Tanjay City

Abstract

Flooding is one of the most destructive types of natural disasters that happen in the Philippines, which not only affects vulnerable communities but, in extreme situations, results in substantial life, livelihood, and infrastructure losses. Tanjay City is one such area that is very prone to flooding because of its geographical characteristics, being situated in areas where there are river systems and low-lying areas, and because of socio-economic characteristics. The objective of this study is to utilize computational approaches to forecast flood-prone areas in Tanjay City by studying the interaction between hazard and exposure. Rainfall intensity is used as a variable in the study of the hazard component, and population density and critical infrastructure are used to study exposure. The integration of these variables into a computational framework provides a quantitative study of areas that are prone to flood risks based on their spatial characteristics. The accuracy of the framework is enhanced by considering data on previous flood occurrences and validation based on previous flood events. The map that was produced showed that areas that are very densely populated and are situated in low-lying areas, near river systems, and coastal areas, are more prone to flood risks. This study shows that even moderate hazards can result in severe outcomes in areas that are very exposed, and it is based on this that there is an interaction between hazard and exposure that multiplies vulnerability. The study identifies hotspots and is very relevant because it shows that computational approaches are useful tools that can be used by planning authorities and other relevant institutions to make informed decisions.

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