Developing Flood Vulnerability Functions Based on Secondary Data: A Case Study for Pakistan

Abstract

Floods pose a significant threat to human life, infrastructure, and economic stability in developing nations like Pakistan, where a 1% increase in floods correlates with a 0.44% decrease in livelihood and a 1.947% rise in poverty levels. With approximately 20% of its land area and 40 million people exposed to flood risks annually, there is an urgent need for robust flood risk assessment tools. Effective flood vulnerability functions are essential for formulating data-driven disaster management policies and enhancing the flood resistance of buildings. However, existing global models fail to capture Pakistan’s unique flood dynamics, necessitating the development of localized models. This study synthesizes global methodologies and integrates secondary data to create reliable tailored flood vulnerability functions. The research reveals a non-linear relationship between flood depth and damage across various building materials, with mud structures experiencing 82.5% damage at 0.5 meters and complete failure at 1.5 meters, while concrete structures show only 3.5% damage at 0.5 meters and a maximum of 65.9% at 3 meters. Additionally, the study highlights that prolonged flooding increases damage by 30-50%. Recommendations include prioritizing reinforced concrete in construction and implementing comprehensive flood risk management plans to enhance structural resilience and community safety in flood-prone regions.