Zhongjiang Park is located in Chengdong New District, a future urban administrative, cultural and business center to the east of the historical city center in Wuhu. The park is an urban green belt covering an area of 48 hectares, which also serves as a landscaping axis connecting Shenshan Mountain and Biandan River. The river, path, hills and forest are the main design elements that are integrated with each other to create “a green ribbon dancing in nature”. In combination with the functional requirement of nearby urban facilities, eight themed parks, including Forest Park, have been designed in the 48-hectare Zhongjiang Park. Low-cost eco-friendly facilities, such as gabions and bioswales, have also been installed, infiltrating the “sustainable” design concept throughout this project.
Unfavourable site conditions became challenges during project construction. The ground texture is mainly composed of silty soil; while the local hydrological conditions are complicated – groundwater level and surface runoff are influenced by seasonal changes, causing floods in some seasons and droughts in others. Consequently, neither channel excavation nor conventional concrete embankment construction was practicable. By employing appropriate grading measures, we turned unfavorable conditions into unique advantages and created a rainwater management system with urban flood control functions and specific landscaping features.
A series of creative designs and implementation strategies were proposed through landscape architecture. Firstly, special terrains were shaped to collect and take full advantage of abundant native rainfall and water resources. Bioswales, wetland planting areas and landscaping water facilities were built to act as a stormwater storage system, replacing the traditional pipeline drainage system. It works well to store water during droughts to maintain moisture and slow down stormwater during floods. Surface runoff flows into bioswales through the special micro-terrains. After being filtered and purified in wetland planting areas, it runs into an artificial watercourse system to achieve a completely natural water circulation mechanism.
Secondly, gabions are built as ecological revetments to cope with the problem of silty-soil ground texture that is impracticable to construct drainage trenches or slopes. The gabions could be easily built and effectively prevent soil erosion.
Finally, several pumping stations were built to control the ordinary high water level of the designed water system at 4.8m in response to seasonal flooding. Water demand in aquatic habitats can be fully supplied by local precipitation based on a thorough analysis of the runoff and evaporation of storm water, also the groundwater supply and permeability. Aquatic habitats can be refreshed every 2-3 months by local precipitation. Thus, both “abundant water” and “clear water” goals can be achieved.
According to the project owner, the landscaping watercourse did not require any additional water supply daily and drainage pumps were used no more than three times within five years after the project’s completion.
This project combines the functions of bioswales and artificial wetlands to successfully create a regional rainwater management system. Moreover, several years after completion, the system has always kept its ideal operation, providing a green lung for the city center of Wuhu.
Location: Wuhu City, Anhui Province, China
Landscape Architect: Shenzhen L&A Design Holding Limited
Li Baozhang, Tang Wei, Xu Zhihua, Wan Xiaofang
Client: Wuhu Business Culture Center construction headquarters
Image Credits: Chill Shine