B. Route In Existing Area
In addition to operating service in entirely new areas, agencies sometimes plan new bus routes operating in areas with existing coverage. These new routes are often limited stop or express versions of existing local routes. Sometimes new local routes are created which provide direct service between two trip generators that currently require a transfer to access.
In areas with existing service, the performance of existing routes is the paramount concern in route planning. Before inaugurating express or limited routes, you must make sure that corridor demand can support robust frequencies on both the limited and local routes. The current trend in American thoughts about frequent transit service is that fifteen minutes is considered a frequent service. Therefore, I would not implement express or limited stop service along a particular corridor unless both the local and the limited stop route can operate every fifteen minutes or more.
In addition to the above, express or limited stop services should not be operated unless a significant amount of running time is saved when compared with the local service (please refer to the section on running time determination for additional discussion). In general, express or limited stop services should not be operated unless the travel time savings when compared with the local service is 10% or greater.
Transit agencies sometimes are tempted to overlay routes on top of an existing grid system that provide direct access between two non-linear points. I suggest that transit agencies think twice before starting such services. Operating a pure grid system is not only the easiest network for the public to understand, but it is also the most efficient to operate. The most productive North American transit systems, places like Los Angeles, Chicago, New York, and Toronto, all operate on a strict grid system. An exception might be made if origin-destination surveys demonstrate that there are enough passengers going between the two destinations to independently support a special route.
As new routes along existing corridors generally already have bus stops and terminus locations identified, there are easier to implement both operationally and politically. However, if overall service levels increase it is important to ensure that adequate layover space is available at least one of the terminals. For more information about layover please refer to the section on scheduling.
Next up: the selection of bus stop locations for your new route, in Part II.