Published
In support of our current theme of radical uncertainty, Julian Ross – Head of programme integration at Network Rail – offers a series of three blog posts exploring uncertainty in the context of the rail industry, of which this is the first.
What if every office worker started working from home? This kind of question would traditionally reside at the far bound of a rail planner’s most extreme scenario.
The fact that the UK’s railway is having to adapt to just such a scenario highlights an important truth ‒ the linear forecasting based upon annual compound growth that has given us today’s railway has, in fact, baked fragility into the system.
By this I mean that the railway system can only effectively address a constrained specification of future travel needs. But, even before short‒term shocks like a global pandemic are thrown in, future demand for travel is uncertain – highly so over the long term. Despite this, we continue to design projects to deliver specific timetables based on single scenarios that claim to predict our journey needs for decades.
Puzzles and Mysteries
To grasp how strange this is, think about the uncertainty surrounding some of the key questions facing a rail planner:
- Quantity ‒ How many journeys am I planning for? Will the economic assumptions behind forecasts prove to be erroneous? How will Covid‒19 play out? Will Net Zero targets lead to unexpected modal shifts?
- Quality – what products will people demand? And use with enthusiasm if offered? The connectivity of a through journey? Mobility as a service? Budget travel? More or different commercial offerings at stations?
- Time – when will people want those services? Will passenger and freight users need changes to their services at a rate faster or slower than expected?
- Space – where should the services go? Where will new housing and jobs be created? And what jobs will disappear? Will Net Zero and Brexit lead to more UK holidays being taken?
In the language of economist John Kay and ex‒Bank of England Governor Mervyn King, many of these questions are mysteries, fundamentally uncertain, yet we treat them as if they were puzzles, solvable through more information and the application of logic.
King and Kaye argue that falling into this trap is dangerous. We end up believing that our models and forecasts are accurate descriptions of the world rather than tools that provide insight. This gives us false comfort. We don’t try to discover what might really be going on because that’s a lot harder and leads us away from comfortable linear models.
This approach leaves the railway fundamentally unable to accommodate redistribution of demand, either in time or space. Or, indeed, to profit from carrying more passengers through better tailoring its offers to meet demand. The only option is major projects, such as Thameslink and Crossrail, which accommodate growth on defined corridors at a cost of many billions of pounds and take a decade or more to deliver. Try comparing that to EasyJet redirecting flights from, say, Spain to Switzerland.
In his subsequent blog, Julian explores what an anti-fragile rail system might look like and in his final blog he explores what all this means for the railway in tomorrow’s railway … today.
Julian Ross, Network Rail