Exploring the Feasibility of Sponge City Solutions for Flood Resilience in Gangnam, Seoul

Abstract

Gangnam District in Seoul faces increasing flood risks due to rapid urbanisation, aging drainage infrastructure, and intensified rainfall linked to climate change. This study assesses the feasibility of implementing Sponge City strategies—such as permeable pavements, bioswales, and rain gardens—alongside the Deep Tunnel Sewer System (DTSS) to build long-term urban resilience. Employing a mixed-methods approach, the research combines GIS-based spatial analysis, flood simulation modelling, SHAP-informed risk prediction, and stakeholder engagement through public surveys. Findings identify spatial hotspots for intervention, highlight strong public support for green infrastructure, and underscore institutional and regulatory barriers to implementation. The study proposes a hybrid green-grey infrastructure pathway tailored to Gangnam’s urban fabric and contributes to broader debates on integrating nature-based solutions in high-density cities facing complex climate and development pressures.