There is growing evidence of an “optimism bias” regarding the attainable performance of tramways or other transit services operating in “type B” right-of-way, pushed by an ill-informed idea diffused in political and planning circles that type B right-of-way and signal priority (a poorly understood problem by laypeople) can yield performances equivalent to a vehicle running in type A right-of-way. In other words, you can have metro performances, but on a budget. Similar to what Bent Flyvbjerg describes for ridership estimates or early cost estimates, there is a tendency in early planning for “strategically misrepresenting” (more or less intentionally) the level of speed performances tramways can achieve.
In
the business case, the LRT options for Finch are estimated to reach an average speed of 22 km/h (page 8), well above the currently scheduled 13.5 km/h. In the early 1990s, the expected average speed for Bologna’s planned “metrotranvia” was set at 20-25 km/h, as was common for that kind of project at the time. The current system under construction is expected to average 17.8 km/h (PFTE and Final Design), or as low as 14.5 km/h in more recent documents (Progetto Esecutivo) that incorporate additional speed restrictions required by the fixed-guideway transit regulatory body, ANSFISA. The same happened in
Bordeaux, where the initial estimates indicated 21 km/h, while the actual running speed is closer to 18 km/h, and as low as 12 km/h in the city center, with many trips showing no substantial improvement over the pre-existing bus service. In Helsinki, there has long been a
target speed of around 25 km/h for LRT in planning documents. However, the realities of the urban environment and the multiple compromises required to achieve other goals, such as safety, urban integration, and coexistence with other modes, have resulted in reduced operational speeds in many recent tramway projects. Only the orbital Jokeri LRT, with its many type A segments, comes close.
