An Evaluation of Multi-Criteria Decision Analysis for Urban Stormwater Management - A Case Study of Anneberg

Abstract

Urban stormwater management is increasingly challenged by climate change and urbanisation, which raise flood risks and pollutant loads. This master’s thesis evalu ates how Multi-Criteria Decision Analysis (MCDA) can support urban stormwater management in a real-world case study: the Anneberg area of Partille Municipality, Sweden. This area is experiencing densification and has steep topography, limited space for stormwater solutions, and a downstream recipient included in the Natura 2000 network. Five stormwater solutions were evaluated: Infiltration trench, Grass-covered infiltration trench, Rain garden, and two hybrid combinations. All alternatives meet the necessary detention volume for a 20-year rainfall event, with a duration of 10 minutes, with a 25% climate factor. A literature-based scoring, ranging from-10 to +10, was applied across ten criteria within environmental, social, economic, and technical dimensions. Stakeholder preferences were gathered through a survey with 31 respondents from four different groups, using a hierarchical direct-ranking method. These groups are personnel at Partille Municipality, researchers, consultants, and property owners. The Grass-covered infiltration trench achieved the highest total score, followed by the hybrid solutions. The conventional infiltration trench scored 0, serving as the reference alternative, while the Rain garden was the only alternative that received a negative score due to high costs and maintenance requirements. The sensitivity analysis showed that the total score of the Grass-covered infiltration trench is robust across different stakeholder weightings, whereas the Rain garden’s score varies substantially. Excluding economic and technical dimensions reversed the ranking, making the Rain garden the top-ranked alternative. In conclusion, Multi-Criteria Decision Analysis is a powerful and transparent decision-support tool for urban stormwater management. It integrates objective per formance data with stakeholder preferences, allowing trade-offs to be systematically analysed and discussed. However, the method must be carefully adapted to local conditions and priorities, and its limitations must be acknowledged, particularly the compensatory nature of the simple additive model and the risk of overemphasising the top-ranked alternative. To strengthen future applications, research should focus on validating scoring with data from installed solutions, comparing weighting methods (questionnaire vs. workshop), and developing better approaches for engaging civil society. When applied with these considerations in mind, MCDA offers a defensible framework for navigating the complex trade-offs inherent in sustainable stormwater planning.