Many discussions here lately have included comments about building networks of “bus rapid transit (BRT) as the truly low-cost solution to our transit woes.
Meanwhile, the TTC regularly trots out a chart showing the relative capacities of various modes. This appears most recently in the Environmental Assessment materials for the eastern waterfront projects. One of the many appearances can be found in the presentation materials for the West Donlands public meeting held last week. (Warning: this file is over 11 mb if you are on a slow link.)
The TTC claims that buses can handle demands of 6,000 per hour or more. Let’s do the math.
The TTC’s standard for vehicle loading for low-floor buses is 55. Yes, it is possible to pack more people on the bus, but this makes stop service extremely difficult because people cannot move around on the vehicle. Also, this is an average load and some buses will be more crowded than others. For 6,000 passengers per hour, you need to operate about 109 buses per hour, or one every 33 seconds. Even if we scale up to articulated buses with 50% more capacity, the headway would still be well under one minute.
Such a headway is totally impractical except for one condition: a line-haul operation where everyone gets on more or less at one place and everyone is going to the same destination. A good example would be the proposed BRT service from Downsview Station to York University.
If buses have to actually stop along the way to let people on and off, the frequent service requires lots of station capacity and passing lanes so that the inevitable express trips can get around the “locals”. Traffic lights (yes there will be traffic lights even on a BRT line) typically cycle every 80-90 seconds, and for obvious reasons it is impossible to give every bus an immediate green.
The effect will be to platoon the buses in groups of two to four, and all of the facilities along the line have to take that into account.
If we are trying to do this in the middle of an arterial road such as Finch or Jane, things get quite messy. Even at 3,000 per hour, the bus headway would be below the level we have ever operated bus service in Toronto. I won’t say anything about the noise because, of course, these will all be “silent” hybrids.
The TTC claims that the projected demands in the waterfront corridors are in the area where buses and streetcars overlap. I beg to differ. These are local services that will make frequent stops, not an express BRT route. The TTC’s claims are highly misleading and give the impression that buses are a viable option when, in fact, they are not. Serious bus traffic jams would result.
This ties back to the Transit City proposals and discussions of alternatives to the Spadina Subway extension. We cannot provide the capacity we seek in the new LRT corridors with a bus-based network.