Diagnosing delivery capabilities on a large international nature-based solutions project

Abstract Nature-based solutions (NBS) are increasingly at the centre of urban strategies to mitigate heatwaves and flooding, improve public health and restore biodiversity. However, on-ground implementation has been slow, inconsistent and often limited to demonstration sites. A broad literature consistently highlights institutional barriers as a major reason for the observed implementation gap. In this study, we developed and deployed an assessment tool to identify barriers to NBS delivery on a European Commission Horizon 2020 project spanning seven cities. We found that practitioners were effectively navigating challenges in the areas where they had significant control, including community engagement, strategy development and technical skills. The greatest barriers were outside the influence of project teams: understaffing, a lack of intra-organisational processes, and risk-averse organisational cultures. These findings emphasise that after cities embrace NBS at the strategic and political level, it is vital that executives follow through with the necessary pragmatic reforms to enable delivery.