Presenter
Prof. Wei Zhang, Beijing University of Civil Engineering and Architecture
Co-author(s)
Mr. Peizhen Qu, Beijing University of Civil Engineering and Architecture
Mr. Zizhen Fu, Beijing University of Civil Engineering and Architecture
Dr. Huichao Sun, Beijing University of Civil Engineering and Architecture
Dr. Xiancai Song, Tianjin Municipal engineering design & research institute
Sub-theme
3. Building Resilience for Disaster Prevention and Mitigation
Topic
Total runoff volume control, runoff peak control, runoff pollution control and rainwater harvesting are key goals of sponge city development, and performance assessment of sponge city development is a prominence procedure in sponge city implementation. Although China's national policies clearly require that sponge cities should be evaluated by modeling or monitoring methods, both methods have several limitations, and there are still some key issues to be discussed in the specific evaluation methods. The purpose of this study is to explore a scientific assessment method for sponge city performance based on on-site monitoring and coupled modeling. A comprehensive evaluation methodology combines the on-site monitoring which including runoff quality and quantity monitoring, and hydrological and hydrodynamic simulation by coupling model of one-dimensional sewer model and two-dimensional surface overflow model, was proposed in this study. A typical building community project and a typical drainage basin project in the national sponge city pilot city were selected to verify the application of the method proposed at different scales. For the typical building community project, based on the monitoring data obtained during rainy season in 2019 and long-term modeling for typical hydrological year, the volume capture ratio of annual rainfall was 85.7%, and the SS annual removal rate was 79.8%, which met the requirements of the project design objectives. For the typical drainage basin project, the volume capture ratio of annual rainfall was 78.4%, and the SS annual removal rate was 68.6%, which also met the requirements of sponge city planning objectives and requirements. Furthermore, the peak flow control and urban waterlogging control performance was also assessed through this assessment approach, and the results indicated that there was no waterlogging under the design rainfall condition within the design return period of the drainage sewer system. The potential waterlogging risk was also effectively identified under the design return period of the major control system, even a higher return period. The performance assessment approach combined coupled modeling and monitoring provided important support for drafting and editing of the Chinese national standard sponge city construction evaluation standard, and it will also provides reference for the research and practice of the construction effect evaluation in sponge cities in the future.