In 2020, the area of sponge city in the built-up area of Guangxi city will reach 20%

The Housing and Urban-Rural Development Department of Guangxi Zhuang Autonomous Region recently issued the "Guangxi Sponge City Construction Implementation Plan in 2020" clearly stated that, by the end of 2020, the area of the sponge city (the area required to achieve the rainwater control target) in the built-up area of the entire region will reach more than 20%.

It is reported that, so far, the region's 14 district cities have all completed sponge city special planning preparation and approval work. The city will be in accordance with the "source emission reduction, process control, system governance" concept of system planning, using "infiltration, retention, storage, purification, utilization, and drainage" and other methods of comprehensive strategy, and carry out the construction of sponge cities in an orderly manner. 

In terms of the sponge construction of building communities, low-impact development measures such as sunken green space, permeable paving, and green roofs can be selected for new building communities according to local conditions to achieve source emission reduction; Buildings and communities should be problem-oriented, eliminate stagnant water points on the site, and ensure the drainage of rain and sewage in the pipe network. At the same time, it is necessary to carry out low-impact development and transformation of green space, hard pavement, and landscape water bodies under the premise of ensuring the landscape effect in light of actual conditions.

In improving the drainage of urban roads and squares, all regions shall divide reasonable water catchment zones based on ensuring the carrying capacity of roads and the function of preventing flooding and drainage. The green space inside and outside the red line shall be considered as a whole, and the road rainwater shall be disconnected to the green space as much as possible, so as to realize the rainwater infiltration, retention, storage and purification before discharge. Permeable pavement is given priority to urban squares, urban slow traffic systems, and public parking lots. As far as possible, the surrounding green space should adopt sunken green space, receive rainwater in the site, control the rainwater runoff, reduce runoff pollution and runoff peak, and achieve source emission reduction.

The "Plan" will also build a sponge-type green space system as an important part of the construction of garden cities and ecological garden cities. Urban parks and green space systems should consider the organic integration of green nets, water nets, and green road nets, and carry out overall design in conjunction with the surrounding water system, municipal facilities, and housing construction. On the basis of satisfying the functions of ecology, landscape, and recreation, simultaneously consider providing space for rainwater retention and slow release in the surrounding area, and improve the functions of rainwater storage and purification in the area. According to local conditions, low-impact development measures such as small and micro wetlands, rain gardens, sunken green spaces, grass ditches, vegetation buffer belts, rain wetlands, rain ponds, ecological banks, and biological floating beds shall be adopted. In areas such as park roads, green roads and parking lots, water-permeable paving methods are used to improve rainwater penetration.