Conference Agenda

Climate change imposes challenges on drainage systems and citizens in urban environments due to more frequent and severe extreme weather events. These challenges can be addressed by incorporating blue-green infrastructure (BGI) into urban environments, for which BGI provides multifunctional benefits beyond the domain of stormwater management. The multifunctionality of BGI and the involvement of multiple stakeholders with heterogeneous interests makes the process of designing BGI and deciding between different options a complex planning problem. We evaluate the performance of BGI options for a Swiss municipality against technical, environmental, social and economic objectives via multi-criteria decision analysis (MCDA). BGI options consist of single BGI elements or combinations; the elements are green roofs, bioretention cells, detention ponds and pervious pavement. We adopt a value-focused approach that integrates model-based and expert-derived performance predictions with preference information elicited from stakeholders. In sensitivity analyses, we investigate the impact of uncertainty in performance predictions and in preference information on the robustness of results. Preliminary results indicate that BGI options featuring bioretention cells perform well for a wide range of typical stakeholders. Reducing uncertainty in preference information has higher impact on the evaluation results than resolving uncertainty in performance prediction.