Future directions in Blue-Green Infrastructure research

As global cities rethink their approaches to urban flood risk and water management in response to climate change, accelerating urbanisation and reductions in public green space, Blue-Green Infrastructure (BGI) is gaining increasing recognition due to the advantages of multifunctional BGI solutions over traditional piped drainage and grey infrastructure. BGI, including green and blue roofs, swales, rain gardens, street trees, ponds, urban wetlands, restored watercourses, reconnected floodplains, and re-naturalised rivers, is designed to turn ‘blue’ (or ‘bluer’) during rainfall events in order to reduce urban flood risk. In addition to managing flood risk and increasing water security, BGI generates a range of socio-cultural, economic and environmental co-benefits that help city authorities tackle other urban challenges and ultimately improve the quality of life of city dwellers.

Extensive research over the last decade has focused on improving knowledge of BGI systems in several broad areas, including: hydrological and hydraulic modelling of water flow through BGI assets; biochemical assessments of sediment and water quality; public preferences; identification and evaluation of BGI co-benefits, and; BGI planning and governance. Emerging research into adaptation pathways, natural capital accounting and social practice approaches for understanding community preferences demonstrate how BGI research is moving beyond hydrodynamic modelling to explore decision making under future uncertainty and placing greater emphasis on the role of community preferences in designing BGI that is accepted and supported by those who directly benefit.

This presentation will explore these emerging research areas, particularly focusing on the need for interdisciplinary research into BGI to enable the challenges and opportunities to be fully appreciated. Current knowledge gaps that present research opportunities in BGI will also be discussed, including the need for rigorous assessment criteria to determine the success of multifunctional BGI systems; greater investigation of the social benefits of BGI and the value people place on different types of BGI; the role of implicit perceptions in designing BGI assets, and; the role of urban watercourses as multifunctional BGI corridors able to safely convey stormwater while boosting water quality, providing multiple urban pathways (active transport, wildlife movements, etc.) and increasing green space in cities.