Urban flood risks and emerging challenges in the Greater Bay Area: the case of coastal megacities

Abstract:

"By the 2050s, more than 120 million people are predicted to settle in the Greater Bay Area (GBA) similar geographical term as the Pearl River Delta (PRD) previously, which covers large coastal cities such as Guangzhou, Shenzhen and Hong Kong. Cities in the GBA are vitally important to China in their socio-economic contributions. From recent evidence, this strongly urbanized area is vulnerable to, and currently facing bigger incidences of, coastal and urban flooding. Flood risk is growing in low-lying coastal areas due to rapid urbanization and increasing flood hazards exacerbated by climate change.

This lecture will investigate the current challenges and solutions to improve flood resilience and address climate change impacts on urban and coastal flooding in the GBA’s coastal cities. Frequent intensive rainstorms, sea-level rise, typhoons and surges threaten large populations and their economic assets, causing severe socio-economic and ecological impacts in the GBA’s 11 cities. Current flood risk management (FRM) in the delta is still predominately focused on using traditional techno-fixes and infrastructure paradigms, lacking sufficient strategic planning and flood protection to develop adequate flood resilience.

Recent urban floods in 2017-2021 in Hong Kong, Shenzhen and Guangzhou were enhanced by storm surges and intensive rainstorms. These floods affected multiple GBA cities and drew attention to flood risk as a major challenge in the GBA’s coastal cities. This review encourages the development of long-term FRM practices with provincial and municipal authorities working together more closely to develop better-integrated regional FRM strategies for the Greater Bay Area."