Natalie Parletta
Natalie Parletta is a freelance science writer based in Adelaide and an adjunct senior research fellow with the University of South Australia.
Imagine living in a city where you can ride or walk to essential services, where the air is cleaner and travel costs are cut in half.
That’s the vision of scientists who have developed a framework for urban planners they say could dramatically reduce the average travel distance to key facilities such as hospitals, schools, parks and supermarkets.
“The era of the omnipresent car for mobility has seriously degraded the quality of life through costly travel and very visible effects on urban wellbeing,” says Yanyan Xu from the Massachusetts Institute of Technology, US, lead author of a paper in the journal Science Advances.
“A new urban planning scheme must be at the heart of our roadmap for years to come. The one where, in less than 15 minutes, an inhabitant can access their basic living needs by bike or by foot.”
In exploring existing city layouts, the researchers identified vast inequalities in access to services due to their unequal distribution.
The ramifications go beyond greenhouse gas emissions and extra travel time, they say – easy access to emergency services such as shelters, ambulances or petrol stations is vital after natural disasters.
This also became evident in the distribution of health care system resources during the COVID-19 pandemic, says Xu.
To develop a generally applicable model, the team analysed the distribution of facilities in three US cities – Boston, Los Angeles and New York – and three Middle Eastern cities – Doha, Dubai and Riyadh.
They accessed population data at a one square kilometre resolution from LandScan, road networks from openstreetmap and facility distribution from Foursquare.
Factoring in population density, they divided each city into population blocks and calculated each block’s travel distances to key facilities, which also included banks, pharmacies, bars, soccer fields, concert halls and fire stations, using existing road networks.
Then they modelled the optimal number of facilities and how cities could redistribute them for better accessibility by all.
The results and models can easily be implemented in all cities, says Xu, as the data they used are publicly accessible. Implementation could, however, be limited by the built environment and investment.
In their paper, the researchers argue that “the planning of the distribution of different urban facilities deserves attention to a paradigm shift toward walkable cities”, acknowledging that future work could explore the dynamic nature of different people’s needs and movements.