Co-creating strategies to implement nature-based solutions for flood and drought risk: insights from the Geul Basin, the Netherlands

Nature-based solutions (NbS) are increasingly promoted to address climate change while delivering multiple benefits. In the Geul Basin in the south of the Netherlands, interest in NbS has increased notably following the 2021 flood. This has led to a growing number of initiatives by both governmental and non-governmental actors. Despite this interest, uncertainties remain regarding which NbS options should be prioritized, accounting for not only their disaster risk reduction benefits but also their co-benefits and stakeholder preferences, and how these measures can be combined and sequenced over time. This study presents the outcomes of a workshop conducted with a diverse group of stakeholders from different sectors in the Geul Basin, combining multi-criteria analysis (MCA) with the adaptation pathway approach. Workshop participants jointly assessed NbS options using agreed and weighted socio-economic and ecological criteria. The MCA results informed the co-development of adaptation pathways, exploring how preferred NbS options can be sequenced under changing climate conditions and identifying enabling conditions, such as governance, financing, and land-use arrangements, required for their implementation.

Results show that participants prioritised flood protection and highlighted the importance of sustainable financial models to support measures in the long term. Based on the ranking of measures, forest-based and wetland measures, such as (food) forests, alluvial forests, and wetlands, emerged as the top solutions. In the pathway exercise, these measures are sequenced later in the timeline, while the enabling conditions necessary for their implementation are already underway at an early stage. Finally, the pathway exercise revealed the importance of combining different measures and upscaling them, given the limitations of a single NbS measure in fully addressing flood and drought extremes. At the same time, land use and financing remained the key conditions for the successful implementation of the pathway.