In my research into weather risks to transport supply and demand, I come across the word ‘resilience’ fairly frequently. I cannot always assume a singular definition, though. Some of the literature uses resilience to refer to low levels of vulnerability to extreme weather conditions or other disturbances; some to the presence of redundancy in a network, such that an alternative means of access can be substituted for any closure; others to the speed of recovery from a time of disruption until systems return to normal. Yet it all comes back to a similar idea. That like a rubber ball, strong yet flexible, designed to bounce back, something is resilient if it is strong enough to withstand the impacts of incidents like severe weather, and/or flexible enough to offer more than one option/way/route to users, and/or bounces back quickly to reasonable levels of performance.
It should be possible to look at any transport network, in any geography, of any mode, and assess its resilience. Ideally, multiple modes and geographies would be analysed in concert, as transport should act as an integrated system. Yet most studies of resilience or lack thereof in the transport discipline focus on only the road or rail networks, and only the private vehicles or passenger trains that use them respectively. This leaves multiple gaps in our understanding of transport resilience to different weather conditions, and one of these gaps is the lack of discussion about the resilience of bus services.
I cannot yet claim to be able to fill that gap, but I have just completed the analysis, write-up, and submission of a brief case study that perhaps starts to bridge it. And this case study indicates that buses might be one of the most resilient modes of transport available.
Furthermore, whilst there is some research into how people behave during disruption, it seems there is less consideration of their awareness of risk and resilience in the networks and services they are using, and how resilient this might make their behaviour. My short case study, however, provides some insight into the behaviour of public transport users, suggesting they are indeed resilient.
If you want to read my case study article, you’ll have to wait for its publication, but the key point is that where buses and rail run in parallel, the bus services are less disrupted, can divert if need be and still deliver the service, and can make up lost time more quickly than rail. The buses also seem to create redundancy, not just for themselves, but for the adjacent rail services. Finally, the number of bus trips rose sharply to and from places where rail passengers were likely to know that buses would be more reliable during the disruption.
I mentioned this to a former colleague, who suggested my discoveries should really be common sense. He also pointed out that the most vulnerable portions of the bus network were the depots and fuelling stations, which could easily be targeted for flood protection measures, for example, compared to the mile upon mile of train tracks needing improvements to resist those floods and ensure the operation of even a limited rail service.
Yet I later heard evidence that buses can be resilient even when the bus depot is inaccessible for many hours. In a talk I attended, a bus company manager explained how he, his drivers, and other staff improvised on the spot to keep a limited service running following a police closure of their depot’s access road. This won them great appreciation from their customers, and a flexibility, a resilience on the part of the not only the bus company and their passengers, but also the entire local community.
So an early finding in my PhD research: buses bounce back better than most transport options, their passengers know it, and the resilience of both buses and their passengers is rather unappreciated in wider transport research and practice.