Author(s): Richard Kellagher, Bridget Woods Ballard, Juan Gutierrez Andres, Vivian Dou
Linked Author(s): Richard Kellagher
Keywords: "LID", "SuDS", "Sponge cities"
Abstract: The rate of urbanisation in China is higher than anywhere in the world. More than 40, 000km2 of land has been developed over the last 35 years, with the number of cities increasing from 193 to 653 and urban populations rising from 170 to 750 million. The Chinese acknowledge that their cities have grown too fast without adequate consideration of vital environmental risks. Beijing's drainage system was built to serve rainfall runoff based on a 1: 1 year or 1: 2 year pipe-full capacity. Water management and pollution from urban runoff was not included in rainfall runoff design criteria. The outcome from this is that flooding and river pollution have become urgent issues: annually more than 100 cities are affected by floods; 234 cities suffered from flooding in 2013 alone. In 2014, direct economic losses from flooding were estimated as RMB 157. 4 billion (�17. 3 billion). The aim of settling an additional 100 million migrant workers in cities over the next 5 years, combined with likely climate change impacts on increasing rainfall intensities, means that economic consequences are significant if these drainage issues are not tackled. Three years ago, the Chinese President announced that new cities and redevelopment would conform to a surface water management �sponge-city� paradigm and China's state council announced a new set of urbanisation guidelines. This paper compares and contrasts the expectations of moving to new sponge city criteria in China with the sustainable drainage criteria used in the UK. The paper details the requirements for each country and then provides illustrations of the performance of sustainable drainage systems in both the UK and China based on applying the respective criteria. Conclusions are drawn on the current state of surface water management in each country and the changes that might lie ahead
Year: 2017