Water as a resource is irreplaceable. Yet heavy rainfall can become a disaster even in modern cities if rainwater is not drained out in time. This was recently evident in Shanghai, Nanjing and some other cities, especially in southern China, where streets looked more like the canals of Venice.

The idea of "sponge city", which emerged in the West and is gradually gaining popularity in China, will hopefully solve this problem. Following the philosophy of "solving a city's problems with its own resources", it aims at storing rainwater, especially during heavy rainfall, to prevent floods and release it for the benefit of residents during dry times. This will also ease a city's water shortage.

The water distributive system has three main parts. First, it encourages the cultivation of "wetlands" and "meadows" in urban gardens, which will help collect water in pools, enable trees and plants to hold water, and replenish the underground water table. In case of water shortage, the water in the pools can be used directly, while more plants mean higher humidity and evaporation which will eventually lead to higher precipitation levels.