Characteristics and effectiveness of water management methods for ‘sponge cities’ in China

In the process of rapid urbanisation, maintaining urban water supplies and reducing flood risks are increasingly serious global problems. To address these issues, in 2013, the Chinese government proposed a development plan for ‘sponge cities’, which involves the implementation of various water management systems for natural storage, infiltration and cleaning of water in urban areas. In 2016, 30 pilot cities were identified. In the work reported in this paper, similarities and differences between the concept of sponge cities in China and overseas rainwater management systems were determined, considering that China could draw lessons from the latter. The construction characteristics of the pilot cities were analysed with regard to the different implementation measures in semi-arid, semi-humid and humid climatic zones to provide a reference for the selection of construction measures in different cities. Taking Xiamen as a case study, this study analysed whether the selection methods of annual runoff and pollution control in Xiamen would be sufficient to meet the implementation goals of sponge cities. The results showed that China's sponge city approach can effectively control urban rainfall–runoff and reduce runoff contaminants, although the plan should continually consider and adapt methods developed elsewhere.