There was a good quote on a BBC article, from the permanent secretary of DfT on passenger demand:
Yet despite not knowing simple passenger demand even a short period into the future, it is supposedly possible to estimate it over many decades, considering its economic value, effects on wider economic activity and the UK economy as a whole. Clearly it isn't.
No organisation or experts can know the shape of the UK economy over that time period, how the economy or working patterns will change so any attempt to estimate and quantify the benefits that far into the future involves so much uncertainty it makes the outcome more dependent on the model and the assumptions than reality, you can make figures support whatever outcome you want.
We can only hope that passenger numbers have recovered by that point such that there's sufficient fare revenue available to support both the existing network and HS2, otherwise I fear the debate will have moved onto saving parts of the existing network ear marked for closure.
Whilst we may not know the exact numbers we can be sure that it's unlikely that we'll be in a position where we'll be looking at what his of the railways we'll be needing to save (& even if we are it'll be very limited in nature).
How can I be so confident in this? It's due to the passenger numbers.
To explain I'll use the baseline of 100 passengers in 2009, by 2019 this had grown to 177 for the flows London West Midlands, London North East and London Scotland (i.e. those routes which would benefit most from HS2 phase 1).
Now to put that into perspective HS2 had used a model of 2.5% growth year on year, so by 2026 (& the opening of phase 1) from the baseline of 100 to 152.
Centrally rail usage has reached 50% of pre pandemic levels (1/2 of 177) so 89 compared to baseline of 100.
However it's unlikely to stop at 50%, at 60% (the worse case scenario predicted) we'd be back above 2009 passenger numbers at 106.
Given that in 2009 we were talking about expanding the network (and indeed we've spent over £30bn on enhancements in that time) any scaling back would likely result in reduction of services rather then the cutting of lines.
However, and neither you or I or anyone can be sure of the exact level, it's likely that rail use will be higher than 60%. Although for this year as a whole is possible that it won't be, however for 2022 it's likely that it will be.
Then it's just a case of how close to the previous 2026 prediction (152) do we get to:
65% would be 115
70% would be 124
75% would be 133
80% would be 142
Now before I go on, the above could happen, but would be unlikely (especially much beyond 2022) given that few companies are taking about 100% remote working with most expecting 2 or 3 days a week in the office and there's still plenty with 10-20% of their staff in at all currently.
As such to be less than 80% of pre pandemic levels commuting (which is about 70% of rail use) would need to have seen a net fall from 70% to 50% (or everyone who used to commuting working an average of 3.5 days in the office and zero people switching from cars). That figure is high for the very reason that there's always been quite large numbers of school children and collage or university students who use rail, that's before you consider those jobs which can't be done in person or those who prefer working in the office.
Back to the list:
85% would be 150
86% would mean we'd reach that prediction of 152
88% would be 156
90% would be 159
Whilst it's possible that those figures may not be reached in 2022, or 2023, there's a good chance that by the opening of phase 1 we could have exceeded the predictions.
Also worth noting is that, whilst likely to be small, reduced car use due to WFH could switch some to rail. For instance a couple with two cars, may change so that for one day a week one of them uses rail so that only need 1 car rather than 2.
