SELECTING OPTIMAL SUSTAINABLE DRAINAGE DESIGN FOR URBAN RUNOFF REDUCTION

摘要

Different changes in the traditional way of managing flooding are being developed or tested in many countries worldwide. It has long been recognized that risk is a central consideration in providing appropriate flood protection and decision making under uncertainty. Besides, flood risk management involves the purposeful choice of suitable plans, strategies and measures that are intended to reduce flood risk. However, the current drainage design practice is still based on the tradition of engineering solutions. Accordingly in recent years the idea to find optimal sustainable drainage design is being recognized through a number of methods which vary from products, material, technologies to reduce flood risks and pollution control. The work described here explains the optimisation component for the selection of robust sustainable drainage systems for urban runoff reduction. The approach has been applied and tested in a case study by coupling a 1D model of the drainage system with an optimisation algorithm. The sustainable drainage design is posed as a multi objective problem based on surface runoff reduction and robustness to uncertain land imperviousness. The results obtained suggest that this approach could be effective in order to reach optimal sustainable drainage design enhancing the robustness of the system to handle events that can become more frequent due to climate change. Moreover, an effective investment strategy for the selection, design and implementation of urban drainage infrastructure can be found. Further work is recommended to expand and generalize the methodology.