A study of the temporal and spatial evolution trends of urban flood resilience in the Pearl River Delta, China

Purpose In view of the increasing threat of flooding across the world and specifically the vulnerability of the Pearl River Delta region to these risks, this study undertakes a spatial and temporal evolution of flood risk in the region, including an assessment of urban flood resilience.

Design/methodology/approach By combining the pressure-state-response (PSR) model and the nature-economy-society-infrastructure (NESI) framework, an urban flood resilience index system is constructed. The order relation analysis method, Criteria Importance Through Intercriteria Correlation method and the VlseKriterijumska Optimizacija Kompromisno Resenje evaluation method, they were then combined to quantify urban flood resilience and reveal the hierarchical relationships that exist between key factors. Using ArcGIS software, the resilience levels of each city are dynamically tracked and compared to reveal the trends in flood resilience over a three-year period.

Findings The results show that annual precipitation and impervious areas are the key factors impacting environmental pressure, while the sewage treatment rate is found to be the key response measure. The cities of Guangzhou and Shenzhen were shown to have maintained high flood resilience indexes (FRI), while Zhaoqing City was the weakest. Flood resilience levels across the Pearl River Delta were found to vary significantly, with the central and southern cities having higher levels than those in the eastern and western regions.

Originality/value This study constructs a new combined method for assessing urban flood resilience, which is suitable for quickly and accurately assessing the short-term spatial and temporal evolution trend of urban flood resilience.