Many changes will occur on the TTC’s network on March 26 primarily with adjustments to schedules in response to lower ridership. This issue was covered previously in:
This article presents more detail about new schedules as well as information on several service reorganizations and diversions.
Updated March 23, 2023 at 10:30 am: The TTC’s map showing the 504 route diversions has been added to this article. Note that it does not match the route description provided in their service change notice.
How Schedules Can Change
When a new schedule is implemented on a route, one or more changes might be happening, and the same changes might not occur in each affected time period. This can produce confusing results as well as communications from the TTC that do not quite represent what is actually happening.
In the simplest case, a route needs more or less service because ridership exceeds capacity or because it has fallen below the level where a reduction is warranted. In this case, the change simply adds or removes vehicles while leaving the travel time unchanged. For example, on a route with a one hour round trip, a 6 minute headway (the interval between buses) would be provided by 10 buses. If two buses were added, the headway would be every 5 minutes, and the route’s capacity would rise by 20 percent.
A variation on this which exists in the current budget tightening era is that the standard for what is a “full” bus has changed. Peak periods have gone back to 100% of pre-covid levels, and off-peak have gone even further, close to peak levels. That undoes the “seated load” standard of the Ridership Growth Strategy that goes back two decades. If the standards allow more crowding, then fewer vehicles are needed to provide the new target capacity.
Other changes can occur independently or at the same time. Most common are adjustments to travel and recovery times in response to changes in congestion and/or construction projects. If a route operates more slowly under new conditions, more buses are needed to maintain the same level of service, or fewer if things speed up. The change in travel time can occur at the same time as changes in crowding standards so that the existing, or even fewer, buses provide less frequent service.
Almost all routes have some recovery time built into the schedule, but this is not a fixed amount. Partly the recovery time deals with expected variations in day-to-day or trip-to-trip travel time, and partly it could simply be included to make schedules work out properly. This is particularly true of branching routes where the time taken by each branch must be such that they blend together, at least on paper. Branching routes with wide headways can have very long recovery times to make schedules “come out right”. Conversely, when such a route has a change, it is possible to accommodate some or all of the change by converting recovery time to driving time.
The TTC has a bad habit of referring to travel time changes as “service reliability improvements” on the assumption that buses are more likely to maintain regular spacing if they have more time for their journey. This is not always borne out by actual operations, and the main effect on riders is that buses show up less often than before the change.
In the lead up to the March 26 changes, changes in headways were listed for several branching routes. The change cited applied to the common part of the route. Beyond the branch point, the change would be double what was originally listed.
Finally, some changes involve route reorganizations that interact such as interlining where two infrequent routes share a pool of buses between them. Combining the two routes reduces the number of vehicles needed for the linked services, while the headways might go up or down as the individual routes are changed to a new common headway.
There is one case in this round where a night bus “service improvement” is really the shift of trips formerly provided by daytime service to the night bus route number, but on the daytime frequency. Looking at the corridor as one route, this might not be as big an improvement as it seems. The same issue can arise when the balance between express and local service on a route is changed. One of the two services might improve, but not necessarily the route as a whole.
I include these caveats in the hope that readers will look closely at their before and after schedules to see exactly what is happening.
For details of changes in specific route headways, travel times and vehicle allocations, please refer to the spreadsheet linked here.Continue reading