ABSTRACT : In accordance with the principle of “water conservation priority, space balance and systematic treatment”, the rainfall will flow to the rainwater garden area through the slope through comprehensive consideration and overall research from all aspects of infiltration, stagnation, storage, purification and use. The detention pond of the rainwater garden will be set with planting layer, active composite soil layer and drainage layer from top to bottom, and a water storage module will be set below the drainage layer. The rainwater will be purified through the active composite soil layer and drainage layer and flow to the water storage module, Subsequently, the water pump is used for landscape water or other municipal purposes. The activated composite soil stores a certain amount of purified rainwater and regulates the amount of irrigation water for plant growth through transpiration.

Keywords -Sponge city; Rainwater and flood management; Rainwater garden;