I. Location of Project

New urban district of Hebi, Henan Province, old urban district of Shaotong, Yunnan Province, Barkhor Street of Lhasa, Tibet.

II. Design Concept

Adhere to the principle of problem-oriented, take account of local conditions, give priority to green development, and adopt a holistic approach.

III. Practice

The phenomenon of "water clears up on sunny days and turns dark on rainy days" is not uncommon in some cities of China. Therefore, the first priority in urban renewal projects is to figure out ways of controlling pollution caused by combined system overflows while taking account of local conditions.

Promote sponge city-oriented community renovation and control the combined system overflow. In the new urban district of Hebi City, adopts targeted policies taking account of the spatial distribution of green space. For stretches of green spaces surrounding the buildings, rain gardens were set up during renovation to absorb rooftop rainwater runoff. The green belts among buildings were transformedsunken green spaces to absorb storm runoff of the hardened paved footpaths. Landscape ponds that are currently lying idle were transformeda wet pond to play the role of regulating and purifying rainwater.

Diversify the use of vacated land and control the combined system overflow. The old urban district of Shaotong City has little available space, and it is difficult to push ahead with sponge city-oriented renovation. Therefore, treatment facilities such as reservoirs and biological filters were set up at the end overflow outlet to treat and discharge the sewer overflow in situ during the rainy season. In addition, considering the urban renewal plan of public space development, the land that were vacated were puta diversified range of use, such method as "fulfilling municipal functions underground + installing parks above-ground" is adopted, a case in point is the reservoir beneath the green area of the park.

Discharge rainwater on the surface and control the combined system overflow. Due to such restricting factors as narrow space and protection of the old city, inside the Barkhor Street of Lhasa City, the combined drainage system was still in use. We then built underground ditches beneath the stone slab to discharge rainwater, achieving the goal of "discharging sewage water underground and rainwater on the surface". Not only was the problem of rainwater discharge solved, such modern facilities as rainwater grates and inspection wells that could have marred the surrounding historical buildings and the flavor of the streets and lanes were also avoided.