On the role of uncertainty in the mainstreaming of nature-based solutions for adaptation to climate change

16:15 Tuesday 28 May

SS013 • OC077

Room S2


Paul Dourojeanni (Chile) 1; Nora Van Cauwenbergh (Belgium) 1; Pieter Van Der Zaag (Netherlands) 1

1 - IHE Delft, Unesco Institute for Water Education

Nature-based solutions (NBS) are promoted by the scientific and policy community as a response to flood and drought risks and damages related to climate change and natural disasters. NBS are seen as particularly interesting in the context of uncertainty and change given their ability to enhance system resilience.

Policy and planning approaches are developed to support implementation of NBS, through inclusion of wider ecosystem objectives and provisions to handle uncertainty. In spite of this support, experiences in the implementation of NBS have identified a deficit in its mainstreaming. Barriers to implementation are often linked to uncertainties in the actual risk reduction that can be achieved and the distribution of costs, benefits and responsibilities. These uncertainties are related to variability, risk and ambiguity in the socio-hydrological systems and the NBS itself. Whereas (strategic) planning approaches address variability and risk, approaches to deal with ambiguity are less developed. This study presents an ex-post analysis of successful implementation of NBS in different EU DEMO sites under the H2020 NAIAD project (Nature Insurance Value: Assessment and Demonstration).

Through a combined analysis of governance provisions and in-depth interviews with key stakeholders, we identify how uncertainties are handled in different planning and implementation steps and highlight the role of ambiguity. The findings contribute to the development of improved approaches to planning under uncertainty and to the creation of an operational framework for the implementation of NBS.