Following up my previous post on the role of perception in transit, I want to discuss the importance of simplicity of routes. In that post I mentioned the relative ease of using a bus that runs frequently. What that omits is the need to know where the bus actually goes. The purpose of most regular bus routes is to provide extensive service for an area, which generally means a winding route with many stops. What immediately follows from this is that it is difficult to be very familiar with more than just the routes you use routinely. This in turn makes it likely that you will simply not use the bus system for getting to somewhere unusual.

I must note that this is not always a predicament in bus systems. In cities with predictable street grids there can be bus routes that go straight along a particular street, or there can be bus routes that follow some important avenue. But inevitably there are common trips that do not follow the obvious streets, and so bus routes evolve to serve those trips.

The complexity of bus routes is a huge part of what makes bus transit a poor way to get people out of cars. A barrier to entry, if you will. If someone is reliant on buses entirely, they have no choice but to take the time to learn the route system, though they might still learn only the part that is relevant to them. Don’t expect people to willingly subject themselves to something difficult and esoteric if they can avoid it.

Though I won’t address it here, some complexity can be mitigated by properly designed information and maps.

The answer is probably some version of Bus Rapid Transit, a term that generally refers to individual lines with separate rights-of-way and express service. I believe bus systems should be holistically planned with BRT ideas in mind, in a way similar to subway systems. This entails simplified routes, limited stops as a matter of course, and maps that make it easy to understand both the overall route system as well as stop locations. Such a system could be parallel to the more comprehensive system. But it would be vastly more usable for most people.

This formulation exposes, however, a serious limitation of even a simplified bus system: the lack of permanent routes. BRT has little infrastructure and its vehicles can travel off route, so it still has this limitation, albeit to a lesser extent. The right way to think about the importance of unchanging routes is probably in terms of temporal simplicity and complexity. A simple bus system that changes over time becomes complex temporally. The effect is that people will still be wary of using the system to inform long-term decisions such as where to live and where to set up a business, as the bus routes could easily change and leave them out in the cold. Here the right sort of Bus Rapid Transit does offer a partial solution, but light rail and subways are and feel more permanent.