Sponge city construction in China: policy and implementation experiences

To deal with the three universal urban water problems - namely storm floods, water pollution and water shortage - China has implemented a comprehensive solution: the Sponge City Construction Project. Sponge cities aim to reduce runoff and pollution, and also to restore downstream ecologies. They combine low impact development methods with grey infrastructures, large-scale flood control projects and rehabilitation. This paper describes Chinese experiences of construction and financing for implementation of sponge cities, which could provide references to other countries for building sustainable, climate-resilient cities and urban water management systems. It illustrates the objectives and methods of the sponge city design and demonstrates the differences in configuration and funding structures in cities of different climates and economic conditions. The total construction area involved in the pilot cities covers 449 km(2). The configurations are distinct due to different economic conditions, climates and land forms: a humid district inclines to drainage-efficient approaches and pollution control devices, while a semi-humid district prefers green infrastructures and rainwater reuse facilities. The Chinese government plays an important role in the funding of sponge cities: Chinese central government provided CNY (sic)20.7 billion for the construction of 16 cities during 2015-2017, while the rest came from local governments and non-governmental investors.