Shape matters: reducing people’s exposure to poor air quality using sculpted infrastructure elements

ABSTRACT

Air pollution in cities disproportionately affects children and those living in economically-deprived areas near busy roadways. Walls are effective in deflecting particulate matter but the addition of shaping either at the design stage, or as retrofit, improves performance. High-wall baffles reduce distal vortex accumulations; On pavements, low-level baffles can deflect suspended particulates back towards the road surface. These shaped structures can scaffold urban plantings and, in tandem, improve the effectiveness of urban green in this context. Shaped baffles are immediately effective, inexpensive and create a win-win that engages stakeholders. This awareness will drive collaborations between planners, designers and modellers for effective and beautiful street furniture elements that reduce pollution exposure.

KEYWORDS:

• Pollution mitigation
• particulate matter
• health equity
• green infrastructure
• exposure reduction
• passive mitigation

Acknowledgments

We wish to thank Helen Ap-Simon and Audrey de Nazelle for their support and encouragement; Rosalind O’Driscoll of APRIL (Air Pollution Research In London) for the opportunity to present and get feedback on this work; Peter Childs of the Dyson School of Design Engineering at Imperial College London for a very helpful conversation and Derek Wilson of TFL (Transport for London) for an opportunity to test these ideas. We also wish to thank the anonymous reviewers who have helped us to improve the work.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors; The National Lottery Climate Action Fund (GB) [Grant number: 20106830].

Notes on contributors

C Matilda Collins

Dr C M (Tilly) Collins is an arborist, ecologist and entomologist with a great interest in urban greenspace.  She is a Senior Fellow of the Centre for Environmental Policy at Imperial College London where she leads a number of projects. Tilly has a passion for trees and insects leading to diverse research interests, most of which have a common theme of using well-gathered data to support sustainable decision-making.  She likes to chat and make links between people and concepts.

Agamemnon Otero

Agamemnon Otero MBE is a founding director of Repowering, Energy Garden and Brixton Energy. He co-founded industry advocacy body Community Energy England and sat on the Business, Energy and Industrial Strategy Office’s Community Energy Contact Group. He has a M.Sc Architecture: Advanced Environment and Energy and previously worked as the director for Renewable Energy Project Finance and Social Responsibility at a financial institution. In 2014 was made a London Leader, in 2016 he was awarded an MBE for services to community energy and in 2017 was named one of the 51 Most Impactful Green Leaders globally by the CSR Congress. 

Huw Woodward

Dr Huw Woodward is a Research Associate at the Centre for Environmental Policy at Imperial College London. His research focuses on pollution dispersion modelling. This includes both national scale modelling using the UK Integrated Assessment Model (UKIAM) to estimate future projections of UK air quality and ecosystem health, and also microscale dispersion modelling, using computational fluid dynamics to investigate the effect of traffic induced turbulence, trees and roof geometry on the dispersion of pollutants within urban areas.