“A sponge city is one that can hold, clean, and drain water in a natural way using an ecological approach,” says Yu, who is helping to coordinate the national project.
Traditionally, Chinese cities handled water well, Yu notes. “But in modern China, we have destroyed those natural systems of ponds, rivers, and wetlands, and replaced them with dams, levees, and tunnels, and now we are suffering from floods.”…
Reverse-engineering a city to make it more spongey requires a mental rather than physical shift, he argues. “It’s a whole new philosophy of dealing with water. It is about how we plan and design our cities in an ecological way. Not about piecemeal, manmade engineering projects. So we need to avoid this kind of trap.”
Sponge-city design could also run up against China’s centralized planning system.
It sounds like this is a major work in progress. As has been found in American cities, such as Chicago, trying to solve flooding issues after the city is a certain size is quite difficult. Are cities really willing to move residents or commercial structures to better deal with water issues? Is it only possible to make changes after a major flood convinces people? The optimal way to do this would be before the development happens as planners and others can set aside space or promote greener options.