At present, some developed countries have very successful experiences and methods in urban rainwater utilization and rainwater collection and use. Most rainwater use in the United States is intended to increase natural infiltration capacity. The United States has built an underground tunnel water storage system and established a surface recharge system, which not only uses the ecological function of floods, but also reduces the pressure on flood control. China now often uses permeable bricks to lay the pavement, and rainwater can be used to a certain extent. However, compared with foreign use systems, it also needs to learn from experience.
German federal and state laws require that rainwater use systems be considered in new or refurbished development zones. Therefore, when developers plan, construct or renovate development zones, they take rainwater as a key content to consider and organize. Especially when constructing large-scale commercial development zones, they also take into account the actual conditions of the water resources in the development zones and adapt to local conditions. The use of rainwater is an integral part of upgrading the development zone. After the collected rainwater is treated, it meets the water quality standard for miscellaneous water and is used for flushing toilets in street apartments and watering the roads and yards.
Many Japanese cities have "sky gardens" with rainwater on their roofs, and have large-capacity underground pools to store rainwater. Various rainwater artificial soaking devices are also built behind many buildings. The collected rainwater is mainly used for flushing, greening, fire fighting and road spraying after treatment.
An experience worthy of reference in the construction of foreign cities is: for any construction project, including buildings, municipal equipment, parking lots, roads, etc., when reviewing and approving, it is necessary to consider and design the amount of stormwater runoff in the area , Can be beared by the municipal drainage pipe network. If rainwater runoff exceeds area