Blue and green infrastructure (BGI) is becoming an increasingly crucial part of modern urban water systems. In the past, water professionals largely used ‘grey’ (concrete) infrastructure, such as pipes and pumps, to provide drainage and flood risk management services, but contemporary best practice increasingly supplements this with designed BGI elements feeding into a wider BGI system. This approach can significantly reduce flood risk by slowing water down and reducing the total quantity that needs to be conveyed at any one time, while also improving water quality by utilising and mimicking natural systems and therefore allowing natural treatment to occur. Finally, by providing space for vegetation, which it also irrigates, BGI supports biodiversity.

 

We identifies three key attributes of BGI that provide health-relevant environmental impacts. Firstly, BGI can be used to promote a healthy physical environment: to diminish noise, reduce heat stress, and improve air quality. Secondly, BGI has beneficial aesthetic and sensory qualities: its appearance, sounds, smells, and tactile qualities can have therapeutic potential even where communities are unable to walk through the area directly (e.g. a pocket park on private land). Thirdly, there are benefits to physically accessible BGI spaces, which can promote exercise and social interaction by allowing a wide range of people with varying mobility needs to pass through them.

Together, these aspects of BGI mean that well-designed spaces can make a very real difference. As well as helping to improve general health and wellbeing, they can reduce social and health inequalities in the UK. Research suggests that such health inequalities are currently widening, at a time when the impacts of climate change are also disproportionately impacting poorer communities. We show that BGI offers the opportunity to tackle these two problems together, and thus to build a society that is fair and sustainable for future generations. The COVID-19 pandemic has reemphasised the topicality of this focus, as the quality of people’s local environments is an issue that has been at the forefront of public debate during lockdown.