Bus Scheduling

The scheduling of regular bus routes involves a number of issues in order to serve passengers efficiently and effectively, with a goal of preventing both overcrowding at one extreme and frequent empty trips at the other. As a process, scheduling follows the placement of a route and the bus stops along that route. (Some such stops may also be used for other routes, when routes intersect.) The intersection of the route with other routes may impact the scheduling process—for instance, it may be desirable to schedule buses to arrive at a [Page 326]given stop a certain amount of time before another bus (or other form of transit) departs from that stop if passengers are expected to frequently transfer from one to the other. The terminus locations may also impact the scheduling, when the route is expected to be used by commuters, in which case trips need to be arranged around work hours and will probably be less frequent later at night. Conversely, routes that connect residential areas to downtown areas need to operate sufficient trips in the after-work hours in order to serve downtown businesses and in some areas may be best advised to operate late-night trips to accommodate the time when entertainment venues, restaurants, and bars close for the night.

Scheduling is also impacted by the changing conditions throughout the day that affect how long it can take a bus to traverse the route. When possible, planners avoid streets with school zones, traffic circles, speed bumps, and other traffic-slowing measures, as well—at the opposite extreme—as major arteries and high-speed streets, where bus stop placement is problematic. Total avoidance of these circumstances is not always possible or practical, and variable traffic patterns throughout the day (the dense traffic of the commute hours, the moderate traffic of the workday, the lighter traffic of after-dinner hours, as well as the impact of school zones, school bus traffic, and other temporal factors) can have a serious effect on the length of time a route may take. Extra routes may need to be added in bad weather, such as in the winter, when the general speed of traffic has been slowed enough that the difference between scheduled arrival times and actual arrival times quickly expands and distorts the schedule.

Scheduling is also affected by dwell time, the time the bus spends in any given place, whether a terminus or a bus stop. Different methods of fare collection impact dwell time, as passengers searching for exact change that must be counted by the driver take longer than passengers who feed exact change into a machine, who in turn take longer than passengers using a machine that can give change back from overpayment, who in turn take longer than passengers using cards or passes that are read electronically. For buses without on-board fare collection—such as school buses, free buses, or ticketed buses whose passengers have already paid at the ticket counter—dwell time is affected primarily by the number of passengers embarking or disembarking at any given stop. Crowded buses can experience greater dwell times as it is more difficult for passengers to find a seat or to board. Dwell time may also be affected by passenger age and similar factors. Schoolchildren can be expected to take longer to board than adults, and routes serving retirement homes will be used by elderly passengers who are slower to move and who should be assured of finding a seat before the bus resumes motion.

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