Day: 2021-06-09

Towards the 30-minute city — how Australians’ commutes compare with cities overseas

| David Levinson

Reprinted from The Conversation by Hao Wu and David Levinson

The ease of reaching urban amenities underpins city life. We led a global research team that compared access to jobs in 117 cities across the globe, including eight capital cities in Australia, and examined strategies that might improve transport in our cities. The newly published research finds access to jobs increases with population and that our two largest cities, Sydney and Melbourne, compare favourably with similarly sized cities overseas.

Transport infrastructure and land use patterns form the backbone of a city. It’s the reason so many people choose to live and work with other people in cities – despite the noise, congestion and negatives of city life – because they can easily reach a variety of destinations. Towards this objective, many planning agencies set themselves a “30-minute city” goal, which is behind many planning decisions.

heat map showing number of jobs accessible within 30 minutes across Greater Sydney

Heat map showing access to jobs across Greater Sydney. Red denotes more jobs and green fewer jobs within 30 minutes’ travel time. Author provided

Read more: Access across Australia: mapping 30-minute cities, how do our capitals compare?

What did the study find?

The ease of reaching destinations can be measured by the number of jobs reachable within 30 minutes. Job locations offer both employment opportunities and amenities; restaurants, schools, hospitals, shopping centres and so on are also job clusters.

The research measured how many jobs were accessible within 30 minutes (travelling one way) for four different modes of transport – cars, public transport, cycling and walking. The 117 cities studied are in 16 countries on six continents. The research finds cities really differ in the convenience of transport, but also finds significant similarities between cities from the same country.

Australian and Canadian cities have poorer car access than US, European and Chinese cities. They have better public transport, walking and cycling access than US cities, but access via these modes is generally not as good as in Europe and China.

Cities in the United States have reasonable car access, but lag behind globally in public transport, walking and cycling access.

Chart showing numbers of jobs accessible within 30 minutes' cycling plotted against population for global cities.

Number of jobs accessible within 30 minutes’ cycling plotted against population for global cities. Urban Access Across the Globe 2021, Author provided

In Chinese and European cities, compact development combined with an intensive network produces the highest access globally across all modes of transport.

Chart showing number of jobs accessible within 30 minutes’ walking plotted against population for global cities.

Number of jobs accessible within 30 minutes’ walking plotted against population for global cities. Urban Access Across the Globe 2021, Author provided

One surprising finding is the middling car access in US cities. Despite the reputation of US cities being built around the car, urban sprawl has made it difficult to reach destinations even by car.

Chart showing numbers of jobs accessible within 30 minutes' drive by car plotted against population for global cities.

Number of jobs accessible within 30 minutes by car plotted against population for global cities. Urban Access Across the Globe 2021, Author provided

This sprawl also exposes the Achilles heel in mass transit and non-motorised modes. Immense spatial separation makes for worse access by public transport and active modes of transport such as cycling and walking. US cities have the largest disparity between public transport and car travel.

Chart showing number of jobs accessible within 30 minutes by public transport plotted against population for global cities.

Number of jobs accessible within 30 minutes by public transport plotted against population for global cities. Urban Access Across the Globe 2021, Author provided

This research also finds access to jobs increases with city population, so reaching a greater number of desired destinations would be easier for people in larger cities than in smaller cities. So, despite traffic congestion, larger cities are still more efficient in connecting people with places they want to go.

However, this benefit has diminishing returns. Doubling the metropolitan population results in less than a doubling of access to jobs.

What are the lessons for Australian cities?

The moral of the story is that we don’t need to choose between the US-style sprawling development and European-style compact cities. We can and should have the benefits of both development patterns. We need both density and a well-developed transport network for better access.

Massive road building alone can improve access by car to only a limited extent. The problem is that investments in road infrastructure are often accompanied by lower-density development. That makes it harder for people who walk, bike or use public transport to reach increasingly separated places.

In cities that do have compact land-use patterns, access to jobs remain high across all modes of transport, including cars. So, despite congestion, it is still easier to reach desired destinations in these compact cities. Roads are not race tracks, and high-speed roadways connecting nobody with nowhere are not better than lower-speed paths connecting people and places.

The Australian government is investing A$110 billion over the next ten years in transport infrastructure. This will have significant implications for the future of our cities. If we want our cities to continue to be vibrant, liveable and accessible by all modes of transport, we will need to keep our cities compact and invest more in public transport, walking and biking.

Urban Findings

| David Levinson

by Somwrita Sarkar, Editor Urban Findings

We announce the launch of a new section of Findings: Urban Findings, following the Findings model of short, to-the-point research findings in the broad field of urbanism. The Editorial Board is here, along with an inaugural set of papers here.

At the start of the process, we sent out a call for papers, through our Editorial Board members. We thank them for generously putting in their own time and effort towards these papers, reaching out to their networks and students for contributions, and generously helping out with the review process. This is more so because this process unfolded in a time that was extremely busy for every academic round the globe, as we grappled with the new shifted reality of combining online and face-to-face teaching, and the new reality of virtual conferences.

The papers focus on a diverse set of issues around Urbanism. The application and novel use of new sources of data, and the development of models and methods in quantitative urbanism is growing by leaps and bounds, as these papers demonstrate. A topical theme was COVID-19, to which we all have been witnesses this past year, and which has understandably, and will in the future continue to, change the way in which we think of cities. The papers span broad application and method areas, from model based creation and evaluation of synthetic cities, to empirical research on people, cities, and housing, across Australia, the US, and Canada, large scale survey design and application, and even meta-analyses such as tracking the presence of Urbanism on social media, and the interaction of climate change and housing. Also observed in the papers is the recurring theme of the close interaction between transport and locational behaviours, and the resulting areas of land use and transport interactions – we truly cannot think of cities without thinking of location (urban) and movement (transport) as an integrated whole. This brings us full circle to the reason why we thought Urban Findings should sit under a common umbrella with Transport Findings.

So, along with the launch, this is a call out for regular submissions to Urban Findings (and Transport Findings), for short, to-the-point research focussed on cities. We look forward to some excellent work!