Tuesday, 9 October 2012

HS2 and the WCML fiasco

No surprises to see some people questioning the HS2 decision in light of the West Coast Mainline franchising fiasco.

My personal position remains unchanged: I'm not convinced by the case for HS2 even on the basis of the existing growth numbers. That said, the WCML fiasco did reinforce my prejudice for the need to present simple headline figures for passenger numbers etc alongside more complex cost-benefit calculations. I say 'reinforced' because my experience on the HS2 Analytical Challenge Panel had already convinced me that only a small number of people are really on top of the modelling work that is being done for these very complex schemes. [Indeed, one of the factors behind my recent decision to resign from the ACP was that I no longer felt sufficiently on top of the details of the economic model to be able to fulfil the challenge role.]

Unfortunately, HS2 (and, I assume, DfT) don't seem to share the same prejudice. So, for example, the economic case for HS2 (updated) predicts that 148,000 passengers will use HS2 each day between Birmingham and Old Oak Common. To my mind, the most helpful way to think about that number is to compare it to current figures. Sadly, this is not a comparison that you'll be able to make easily on the basis of information provided in the economic case. Likewise, I'd find it helpful to see user numbers by station compared to current user numbers. Again, not information that you'll find provided in a simple format anywhere in the report. Without these figures I find the more complex calculations even harder to assess.

In short: Simple descriptive statistics help provide context and allow ballpark assessment of more complex analysis. If nothing else, let's hope that DfT and HS2 ltd learn that particular lesson from the WCML fiasco.

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