Enhancing blue-green infrastructure in German cities with the involvement of urban society: insights from Frankfurt/Main and Stuttgart

Enhancing blue-green infrastructure (BGI) will help cities adapt to climate change. This study focused on urban society, specifically on residents, the housing and real estate sector, and municipal administration in the cities of Frankfurt and Stuttgart, and investigated ways to enhance BGI in line with their perceptions, expectations and requirements. A particular emphasis was placed on periods of hot, dry weather. During future workshops, actor analysis, expert interviews and two expert workshops, the positions, level of knowledge and attitudes of the various groups were examined and barriers to BGI identified, in addition to discussions about measures to overcome these barriers. The results showed that within urban society the greatest support for BGI comes from residents, followed by municipal employees, while actors in the housing and real estate sector are the most reluctant. It became evident that there is a need for action to overcome a range of barriers. Overall, political backing, alliances between stakeholders, encouragement of the housing and real estate sector to take action, and a focus on initiating action in selected urban areas are recommended for successful enhancement of BGI. To ensure maximum impact, there should also be a combination of bottom-up and top-down activities.