Shifting to a compact cities model and increasing active travel could reduce the incidence of cardiovascular disease in Melbourne by almost 20 per cent and type 2 diabetes by 14 per cent, research published in the Lancet has shown.
The research forms part of a three-part series by international experts led by University of Melbourne professor of urban transport and public health Mark Stevenson, who says it is the first to quantify the relationship between land use, transport systems and population health.
Key interventions were identified that together could lead to increased walking, cycling and public transport rates, as well as decreased car use. These include having shops and services within walking distance, providing a mix of employment and housing across the city, reducing the availability and increasing the cost of parking, installing safe walking and bicycle infrastructure, providing quality open space, and making neighbourhoods convenient for public transport.
The model was applied to six cities – Melbourne, London, Boston, Sao Paulo, Copenhagen and Delhi.
Within the model, land use density in each city was increased by 30 per cent, average distances to public transport reduced by 30 per cent and diversity of land use increased by 30 per cent. A shift from private car usage to either walking or cycling was also factored in, a target already in place in some European city policies.
The researchers said the target was pragmatic for cities like Melbourne, where currently about 14 per cent of trips by motorised vehicle are for distances of less than five kilometres. This distance is feasibly replaced with cycling or combined walking and public transport, they said.
Applying the model led to health gains across all six cities, with the largest gain in cardiovascular health. It also led to increases in physical activity rates, likely reductions in the incidence of Type 2 Diabetes, reduced obesity and reductions in air pollution from transport emissions.
At the same time, however, the model predicted an increase in road traffic accidents for cyclists and pedestrians of approximately six per cent in Melbourne, translating to around 257 additional road injuries and 10 deaths a year. The researchers said this showed policies promoting walking and cycling must be matched by improvements to infrastructure to separate motorised transport from pedestrians and cyclists.
“The effect of interventions that encourage cycling and walking was particularly evident in highly motorised cities such as Melbourne, London and Boston, and underscores the importance of transport policies, pricing and regulation that encourage active transport via cycling, walking and public transport while discouraging private car use,” University of Melbourne professor of urban transport and public health Mark Stevenson said.
“These changes also need to be matched by improved pedestrian and cycling infrastructure to protect cyclists and pedestrians. Our study shows that these changes at city level could lead to real health gains.”
Another author of the series, Professor James Sallis from the University of California, San Diego, said that while city planning policies could affect health either positively or negatively, “it is clear that many city leaders around the world are not applying the lessons of research to make cities as healthy as possible”.
“A continuing challenge is to improve the communication of this evidence to city leaders and find incentives for them to seek out and apply the evidence,” he said.
“A major incentive is that designing cities for health and active transport, rather than automobile-dependence, also makes the cities more environmentally sustainable helping cities to achieve the UN’s Sustainable Development Goals.”
University of Melbourne Professor Billie Giles-Corti, director of the McCaughey VicHealth Community Wellbeing Unit and lead investigator of the NHMRC Centre for Research Excellence in Healthy Liveable Communities, also contributed to the research.
Professor Giles-Corti said that just as city planning was key to cutting infectious disease outbreaks in the 19th century through improved sanitation, housing and separating residential and industrial areas, the opportunity today is for planning to reduce non-communicable diseases and road trauma and to promote health and wellbeing more broadly.
“We concluded that focusing on walking and cycling infrastructure alone is critical but not enough – to create cities that promote health needs joined-up policies and input across multiple sectors: land use, transport, housing, economic development, urban design, health and community services, and public safety,” Professor Giles-Corti said.
Rethinking autonomous vehicles
Curtin University Professor of sustainability Peter Newman welcomed the research findings, and said it showed cities built around cars were unhealthy.
“This is a powerful new statement on the need for cities to reduce automobile dependence,” he said.
“The evidence has been mounting for some time that suburbs built around the car are not healthy and the health profession has been quite slow at reaching the need to stop urban sprawl, but I welcome it.”
Professor Newman said autonomous vehicles were not the answer to city planning problems.
“At a time when the motor vehicle industry is running a campaign that autonomous vehicles will transform our cities, it is important to say very clearly that people sitting for long periods in cars, whether driving or being driven by a computer, is not healthy. We need to walk and cycle more or use motorised transport for short distances only,” he said.
“Our evidence published recently in The End of Automobile Dependence shows that cities which are walkable are more wealthy, as well as being more healthy and using less fuel.”
RMIT University’s Professor Jago Dodson agreed, saying car-based urban transport policies had been a failure for health as well as for city amenity and liveability.
“The publications’ emphases on walking, cycling and public transport as key factors in urban population health should be clearly heeded by policy makers,” he said.
Professor Dodson also called for a rethink of transport planning institutions.
“Australia’s transport agencies were designed for the automobile age. They need to be reconfigured for the new era of sustainable and active transport.”