When does your commute begin? Visualising Opal data

A growing number of public agencies are starting to release big datasets to the public. These new open source datasets are large and complex, however they can provide the opportunity to gain a much better understanding of how cities and regions function.

The recent release of Opal data^[1] from Transport for NSW has the potential to provide a better understanding of commuter patterns, infrastructure requirements and public transport usage. Opal cards were introduced in late 2012 and have since been integrated across all modes of public transport in NSW (bus, train, light rail and ferry). The much anticipated first release of Opal data included a two week sample of Opal card tap on and offs^[2]. Using this dataset SGS mapped and analysed daily train commuter patterns across Sydney.

By pressing the play button on the bottom left slide bar of the map, the animation starts. The orange lines represent Sydney’s train network and the blue bubbles show the hourly number of tap ons^[3] at each train station during an average workday^[4]. Hover over any station to see when it experiences the ‘morning peak’ – the largest amount of tap ons from 5am to 12pm.

Analysis of this new data reaffirms two clear patterns which are often talked about anecdotally:

1. The highest simultaneous usage across the entire network happens at around 8am

2. The morning peak occurs earlier at stations further away from Central Station.

Assuming that most people use the train network to get to work during the morning peak, and knowing that the majority of jobs are located in Sydney’s CBD and Global Economic Corridor^[5], we start noticing various morning “peak zones”. For example, for people who live in close proximity to these employment locations and well serviced train stations, such as St. Leonards, Bondi Junction or Sydney’s Inner West suburbs, it is sufficient to catch the train at around 8:30am. However, the majority of stations in Sydney’s far (South) West experience the morning peak at around 7:30am; with some happening as early as 6:30am (Kingwood, Werrington, Windsor).

These insights confirm the existing paradigm that Sydney is a predominantly monocentric city and stresses the importance of further developing the polycentric model in order to improve the quality of people’s lives, reduce travel times and congestion. This would also spatially disperse the usage of the train network infrastructure more evenly and reduce the existing strain, particularly occurring during the afternoon peak (see current tap on patterns around 5pm).

Footnotes

1. Opal cards are smartcard tickets that you keep, reload and reuse to pay for travel on public transport.

2. https://opendata.transport.nsw.gov.au/dataset/opal-tap-on-and-tap-off

3. When entering a public transport vehicle or station, you have to validate your opal card by “tapping on”. This analysis doesn’t encompass “tap offs” which are required while exiting the vehicle/station.

4. Monday – 25th of July 2016

5. https://www.sgsep.com.au/news/latest-news/jobs-growth-sydneys-global-economic-corridor