Sustainable measures for mitigation of flooding hazards: a case study in Shanghai, China

Global warming induces temperature variations and sea level changes for a long period of time. Many coastal cities around the world have experienced the harmful consequences of sea level changes and temperature variations. The city of Shanghai in China also suffers from the serious consequences of these two climatic factors. The geological and climatic conditions of Shanghai make it sensitive to flooding risks during heavy rainfall events. This paper analyses the conditions of sea level changes, temperature variations, and heavy rainfall events in Shanghai. Correspondingly, eustatic sea level change, tectonic movement of the continent, and land subsidence in Shanghai have effects on sea level changes. Correlation analysis indicates extraordinary short duration rainfall events have a relationship with temperature variations due to global warming. Moreover, the number of extraordinary torrential rainfall events also has a correlation with sea level changes. Pluvial flooding and potential damage to coastal structures are more likely to have serious effects as the number of flooding hazard events due to global warming and sea level changes increases. This study also established that to efficiently protect the environment, control economic losses, and prevent potential hazards, extra countermeasures including monitoring, forecasting, and engineering technology treatment should be adopted. Monitoring measurements combined with a database system on a website was found to be useful for forecasting and simulating flooding hazards. For systematic sustainable urban water system management, appropriate treatment technologies, such as sustainable urban water system, which can control and manage water quantity and quality, namely “the Sponge City”, should also be considered.