Unlocking urban blue-green infrastructure: an interdisciplinary literature review analysing co-benefits and synergies between bio-physical and socio-cultural outcomes

ABSTRACT Conventional methods of urbanization and risk management have exposed communities to multiple climatic, ecological, and social vulnerabilities. Urban blue-green infrastructure (BGI) refers to a range of nature-based approaches to mitigating the impacts of hazards and enhancing the connections between natural and social capitals, with a particular focus on the presence and management of water elements. However, the bio-physical benefits of BGI are often prioritized over a wider range of potential social-ecological co-benefits. This article draws on a narrative literature review to present the bio-physical and socio-cultural co-benefits of urban BGI, and to examine the relationships, synergies, and trade-offs between these. This review identifies a wide range of socio-cultural and bio-physical benefits of blue-green stormwater infrastructure, including improved mental and physical wellbeing, enhanced cultural connections and values, strengthened social cohesion and sense of place, amelioration of urban heat island effects, reduction of flood risks, improved water quality, and enhanced biodiversity. A number of environmental and socio-cultural trade-offs were identified between these co-benefits, however, including the presence of negatively viewed insects and plant-produced allergens. Aimed at expanding knowledge on the effective implementation of urban BGI to achieve such outcomes, this review highlights wider co-benefits and relationships between them.