The designed Drainage River has changed from a river with single drainage function to an artery of the downstream sponge city, and the new relationship between city and river has changed to symbiosis of city and water and common emerging with the nature.
Rivers are used as the venation to build a blue resilient network of urban built-up areas. Three strategies have been put forward: large-scale - green vein - build a resilient river system, medium-scale - blue city - develop inclusive city-river relationship, and small-scale - oyster township - rejuvenate historical sanatory community.