Session C7 - Stakeholder and citizen engagement

Rainwater harvesting systems (RWHS) primarily aim to turn precipitation into a supply source.  While safe reuse must be ensured through continuous quality monitoring, the potential of systems to control urban runoff remains valid. Integration of RWHS into urban environments, as a type of green infrastructure, requires a multi-criteria decision-making that urges the inclusion of stakeholders and municipal departments in planning processes. This study incorporated a multi-disciplinary approach to facilitate the broader adoption of RWHSs in the Canadian urban context. Monitoring harvested water quality across multiple systems over two years demonstrated the key influence of the systems’ design, highlighting the need to develop detailed recommendations on the design, operation, and maintenance of the systems. The study of public perceptions and the spatial suitability analysis through stakeholders’ participation also emphasized the significance of systems’ design constraints and their influence on supply quality as essential criteria to be integrated in RWHSs’ urban planning. The general satisfaction of users with the systems has a moderate but statistically significant association with their satisfaction with the harvested water quality. Moreover, from the stakeholder’s point of view, the spatial placement of RWHS should be maximized in the sites that minimize the system’s exposure to contaminants.

Urban landscape management often fails due to diverse community perceptions and needs. To address this, policymakers must reconcile these differences for equitable governance, especially in planning nature-based solutions (NBS) for urban biodiversity. Our research focuses on understanding human values, perceptions, and behavior relevant for NBS design and implementation, in urban ecosystems, particularly around two urban rivers in Belgrade (Serbia) and Sydney (Australia). Using community surveys, behavioral mapping, and interviews with local officials, we found that users prioritize naturalistic, humanistic, and utilitarian values in green spaces. While NBS systems address some values like ecological significance, they lack integration with recreational and cultural spaces. Local governments express interest in adapting NBS to community needs but lack expertise and community engagement. To optimize NBS development, socio-cultural considerations and community values must be integrated, balancing biodiversity with community needs. Governance can leverage gaps between user beliefs and behavior to optimize management actions.

The need to transform Brazilian cities to become more resilient in the face of advancing urbanization and climate change requires improvements in areas most vulnerable to disasters. The National Secretariat for Peripheries of the Ministry of Cities, under the Brazilian federal government, recognized the necessity of turning peripheral regions into greener spaces through the use of nature-based solutions. Consequently, in 2025, the “Resilient Green Periphery” public call was launched with the primary objective of reducing hydrological, geotechnical, and high-temperature risks, combined with inclusive adaptation through participatory community planning. Seven initiatives were selected across Brazil, with project proposals ranging from BRL 1.5 million to BRL 2.5 million, totaling BRL 15.3 million for training and implementing nature-based solutions such as rain gardens, evapotranspiration tanks, and stormwater planters, among others. All initiatives will be carried out by civil society organizations operating within the communities. The project began in December 2025 and is scheduled to last 18 months. The intention is to expand the scope of this project so that it becomes a permanent public policy, reaching Brazilians living in the country’s most disaster-prone regions.