Perceptions of blue-green and grey infrastructure as climate change adaptation strategies for urban water resilience

Blue-Green Infrastructure (BGI, including swales, green roofs, and wetlands) plays an important role in reducing vulnerability to climate change risks such as flooding, heat stress, and water shortages, while enhancing urban environments and quality of life for citizens. Understanding the perceptions that professional stakeholders have of BGI is fundamental in addressing barriers to implementation. A novel application of the Implicit Association Test (IAT) is developed to investigate and compare implicit (unconscious) perceptions of blue-green and grey infrastructure with explicit (conscious) attitudes. This is the first time an IAT about BGI has focused on professional stakeholders. Blue-green and grey infrastructure are perceived positively by the sample population. Overall, respondents implicitly and explicitly prefer BGI to grey infrastructure, and regard it as safer, tidier, more attractive, useful, valuable, and necessary. The individual positive explicit perceptions of grey infrastructure, nonetheless, suggest that integrated blue-green and grey systems may be preferable for professional stakeholders to incorporate into water management and climate change adaptation strategies.