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When the first Cobb and Co coach ran from Melbourne to Bendigo, it left the Criterion Hotel in Collins St every morning promptly at 6:00am (Sundays excepted).
They overnighted in Castlemaine and were off at 6:00am the next day for Bendigo. A timetable en-route may well have read “Cobb and Co to Castlemaine will be here at 12:30”.
If you were in Keilor, Gisborne or Woodend, you had a pretty good idea when the daily coach was coming through and you would get to the stop with time to spare.
Speed was important, so drivers would sound a bugle one mile out and groomsmen would ready the next team of horses to minimise changeover time. If you were a passenger and you happen to miss the coach, there was always tomorrow. (Unless, of course, it was Sunday.)
Headway Management for bus public transport
Having published them, we as transport professionals strive to deliver on our promise. Broken axles, muddy tracks and floods may have been replaced with rail crossings, car accidents and unrelenting peak hour delays but all these challenges must be overcome to keep services running to the timetable.
As public transport demand grows, service frequencies increase.
Eventually a service becomes so frequent a passenger no longer needs a timetable; they know they can just roll up at the stop and a bus will shortly pick them up. This then removes the need for a timetable at the stop, as a notice that a bus will be at the stop in less than 10 minutes will suffice.
This situation portrays a 10-minute headway. Running this in theory is straightforward: start a trip every 10 minutes and run all buses to time. At least, that is the plan – but unfortunately, traffic and physics failed to read the playbook, so what is delivered is often very different.
Buses get delayed for many reasons: traffic, large crowds at a stop, elderly people looking for change – the list is as long as it is entertaining. Despite our best efforts to meet a timetable, certain issues refuse to go away: for example, when a bus is caught in heavy congestion, it is really hard to move it faster than the cars!
From a customer experience perspective, passengers generally have a high-level understanding of how traffic (and other circumstances beyond an operator’s control) can cause delays. What they don’t understand is why this will result in a really, really long wait succeeded by two buses showing up at the same time.
Operators try and deal with this through planning. Two common techniques are:
To keep the routes short (reducing the ability for the headway to get too large), and
To introduce more layover at timing points (giving buses the opportunity to reset).
However, these methods are at odds with high frequency services. Whilst increased layover helps get back to the timetable, it is not popular with passengers.
Sure, you could fire off a bus from the terminus every 10 minutes, but there is no way to control these services other than having a supervisor with a clipboard standing by the roadside with a watch, manually timing the services and talking to drivers as needed.
Even gathering performance data will be difficult, as resource restrictions mean you can only measure how each bus is progressing at a small number of points along the route. Compounding this, drivers will not be able to see the vehicle ahead of them on their current route.
The result is that real-time intervention is almost impossible and headway management generally happens after the fact.
It is designed to present the public with as close to a consistent arrival time as possible, even if there are service delays. It helps operators spread the buses out so that two buses on the same route do not arrive at the same stop together.
When combined with high frequency services, headway management even eliminates the need to publish timetables and gives passengers the confidence that a bus will be arriving very soon.
Although there is a lot of talk about headway-managed routes being the latest big thing, it is not new. Shuttle bus services are often run on a headway basis and a number of high frequency routes in many cities have long been advertised as ‘turn up and go’. However, they were manually controlled or not controlled at all.
Technology has reached a point where public transport authorities can now deliver on the promise. Some examples of agencies where this is done are:
There are many other progressive cities across the world where headway is used to measure regularity, including Barcelona, Milan, New York, Paris and Vancouver [3]. In Australia and New Zealand, regularity is typically measured by on-time terminal departures. However, the limitations this places on delivering better customer outcomes are now becoming more widely recognised.
The possibility of technology changing this paradigm sparked a great deal of interest at the UITP ANZ Customer Experience Roundtable in August 2018, with many attendees recognising the benefits that effectively-managed headway can bring to all stakeholders.
KPIs and Metrics
To track service reliability, authorities have used:
Each technique has its own benefits and drawbacks [3], but EWT has emerged as the indicator of choice. For high frequency services, EWT is an objective measure that can be calculated across routes and is relatively easy to fold into operating contracts, with a history of producing excellent results.
Passengers are the immediate beneficiary of the right metric and good headway management because irregularity in headway discourages commuters’ use of public transport [4] and increases passenger discomfort [5]. Furthermore, as passengers on high frequency routes are more likely to arrive at the stop randomly [6], a small improvement in EWT will deliver the best outcome to the most passengers.
By measuring EWT and encouraging operators to reduce this, transport authorities will consistently deliver better services that passengers can rely on.
Public transport companies also benefit from the use of EWT as a metric. The core technologies used to monitor and report on EWT give operators an instant view of operations for both scheduled services and headway services. Whilst both service types are scheduled in the normal manner, once they start running there is a need to clearly identify each route by type and give operators continuous EWT statistics on all routes.
Another key tool is the development of automatic alerts on Bus Bunching. This lets operators see issues whilst they can be fixed and before they become too serious.
The right technology will bring transport authorities a real-time view of the transport network, but more importantly it will monitor and measure headway.
It should deliver the right visibility and controls to operators and allow them to adjust operations in real time to meet EWT targets. This ensures that buses arrive with greater regularity and improves the level of service delivered to the public.
To encourage operators to be proactive and course-correct services in real time, transport authorities can offer substantial performance bonuses as an incentive. Transport for London, for example, pays up to 15% of the contract value in bonuses.
Just like the Cobb and Co services from Melbourne to Bendigo, the delivery of headway is dependent on a number of factors.
Freeman Cobb saw the opportunity for improved services and filled that need with high-speed services, enabled by changing stations every 15 miles and the right technology (in Cobb’s case it was imported Concord coaches, which had been designed for travel in the American West).
Transport authorities must have a similar vision to drive service change. They need to put the right headway management technology in place to drive operators to achieve a higher standard of service delivery KPIs.
Operators then need to be focussed on making this work. Management personnel in these companies must adapt and accept that they need to be even more closely partnered with their drivers than normal, as it is the driver who must make use of the information the tools provide and self-manage the gaps between buses.
Only the passenger needs to do nothing as properly delivered, headway-managed routes will give them a better service, with less waiting and higher levels of reliability.
When Henry Lawson wrote ‘The Lights of Cobb and Co’, perhaps he could sense the excitement of the public for a better transport system. That excitement is still here today – it is up to us to deliver on the promise. Headway management can help us do just that!
References
[1] Transport for London, “London’s Bus Contracting and Tendering Process, lbsl-tendering-and-contracting.pdf,” Transport for London, London, 2015.
[2] B. S. C. t. I. S. T. t. BCM, “Bus Services Continue to Improve Since Transition to BCM,” 04 09 2017. [Online]. Available: https://www.lta.gov.sg/apps/news/page.aspx?c=2&id=752cc877-00a8-4e0c-8732-11e3d8ffa126.
[3] M. Trompet, X. Liu and D. J. Graham, “Development of key performance indicator to compare regularity of service between urban bus operators,” Transportation Research Record: Journal of the Transprotation Research Board No. 2116, pp. 33-41, 2011.
[4] A. Polus, “Modeling and Measurements of Bus Service Reliability.,” Transportation Research, Vol. 12, pp. 253-256, 1978.
[5] M. Simeunovic, M. Lekovic, Z. Papic and P. Pavle, “Influence of vehicle headway irregularity in public transport on in-vehicle passenger comfort,” Scientific Research and Essays Vol. 7(32), pp. 2874-2881, 2012.
[6] D. R. a. G. C. Csikos, “Investigating Consistency in Transit Passenger Arrivals: Insights from Longitudinal Automated Fare Collection Data,” Transportation Research Record: Journal of the Transportation Research Board, No. 2042, pp. 12-19, 2008.
Bus, Trams/Light Rail, Ferry
Intelligent Transport Systems