The Sponge City

The sponge city means a new concept of rainfall flood management in China. The theory of sponge city has been proposed at 2012. The main purpose of this theory is that enhance ecosystem functions of the city and reduce the condition of urban flood. According to the picture, the sponge city could collect rainwater by rainwater recycling system (e.g. green roof, bio retention facility and transparent ground surface) and reuse this when necessary. The sponge city system includes permeate, purification, water storage, reuse and discharge. The measures of sponge city cover rain garden, permeable pavement and so on. In addition, the sponge city project need maximum protection the original rivers and lakes, wetlands, ponds and ditches from development activities. The benefits of sponge city project include energy saving, emission reduction and relieve heat island effect. Moreover, the future layout of urban planning should consider green infrastructure to support sponge city system.

The sponge city project also learning case study from other countries, such as high efficient water-saving in Germany, storm-water engineering in Switzerland, storm-water drainage system in Singapore.

Reference: The Xinhua News Agency, 'The sponge city', 

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