The Problem of Scheduled Service Irregularity

In a series of articles, I reviewed the quality of service on many bus routes during a period, the lull in traffic and demand during the pandemic, when it should have been relatively easy for the TTC to operate reliable service.

A consistent factor on almost every route was that buses are running in bunches with wide gaps between them. Those gaps translate to crowded buses followed by lightly-used ones, and riders rightly complain about long waits and an uncertain arrival of the next group of vehicles.

The TTC argues that service is not really that bad because they have a large number of unscheduled extras (aka “RAD” or “Run As Directed”) buses that do not show up in vehicle tracking records. Leaving aside the obvious need to track all service, not just the scheduled buses, this does not explain why buses run so close together so much of the time. These are tracked vehicles that have a schedule that should keep them apart.

Or so one might think.

TTC Service Standards include provisions for headway quality (the reliability of spacing between vehicles), but this is fairly generous, and it is never reported on as an official metric of service quality.

However, another problem is that on some routes, the service is actually scheduled to come at uneven headways. This arises from three issues:

  • Some routes with more than one branch have different frequencies on each branch. This makes it impossible to “blend” service with, for example, alternating “A” and “B” destinations.
  • In response to the pandemic, the TTC quickly adapted schedules by cancelling all express buses, and selectively cancelling individual runs as a “quick fix” to avoid complete schedule rewrites across the system. Where local trips were cancelled, this created gaps in the scheduled service.
  • On many routes, notably those that formerly had express service, the TTC scheduled “trippers” to supplement the basic service. However, these trippers were generally not scheduled on a blended basis leaving riders with scheduled, but erratic service.

In some cases, the September and October schedules corrected some of these problems, but many persist. This article looks at a number of routes where the summer (August) schedules had uneven headways to see what, if anything, has changed by mid-October. (The most recent set of schedules went into effect on October 11, 2020.)

All of the data presented here were taken from the TTC’s schedules as they are published in GTFS (General Transit File Specification) format for use by travel planning apps. This almost exactly matches information on the TTC’s online schedule pages.

In the charts shown here, there are three sets of data, although they are not always all visible, one each for schedules effective in August (blue), September (red) and October (green). Where the same schedule is in place for more than one period, then one or two of the colours may be hidden.

In many cases, there will be brief changes in headways when vehicles enter or leave service and headways adjust to the new or lost vehicle. However, when spikes and dips are repeated, this indicates pervasive scheduled gaps caused by missing runs and/or by “blended” services that are not on compatible headways.

A common pattern on routes is the presence of “trippers” that are in service from the AM peak until about noon, and again from roughly 3 to 9 PM. These are usually a replacement for a previous 9xx express service, but they are not scheduled on a compatible headway with the underlying base service causing swings between wide and short headways.

For each route, I have chosen one point to be representative. The scheduled service varies by location, time of day and direction, but the overall patterns are the same.

It is my understanding that the TTC plans to deal with the remaining problems illustrated here in coming months. However, it is worth seeing just what has been done to place complaints about irregular service in the context of the large scale schedule changes that were implemented on very short notice in May 2020.

7 Bathurst

For 7 Bathurst, the August schedule had repeated gaps caused both by missing runs, and by trippers that were not blended evenly into the service. The long headways in the early afternoon correspond to the period between the end of AM tripper service and the start of PM trippers.

The schedule was changed in September and the headways are now much more regular through the day. (Only October’s green line shows because the red September line is “hiding” under it.)

24 Victoria Park

The schedule for 24 Victoria Park in August and September (red) contained many trips that were scheduled on headways of one or even zero minutes. This was the combined effect of mismatched headways on the 24A and 24B services plus the presence of trippers on their own distinct headway. In the early afternoon, the trippers disappear for a few hours leaving underlying service with some wide gaps and bunching.

This was improved somewhat in October, but the headways are still inconsistent until the evening.

[Note that where a fractional headway is involved, the scheduled headway will oscillate between whole minute values. A 9’30” headway (9.5 minutes) is actually scheduled as alternating 9 and 10 minute intervals.]

The TTC’s online timetable is included for comparison. Note that there are 24B Consumers Road trips at times one minute apart, and although the 24A Steeles service appears to be planned at 10 minutes, there are scheduled 20 minute gaps (e.g. 8:18 to 8:37, 10:05 to 10:25. 10:45 to 11:05).

Source: TTC Timetable for 24 Victoria Park Weekdays NB at St. Clair

25 Don Mills

The south end of the 25 Don Mills route has regular headways, but things are different north of Don Mils Station.

In August (blue), the evening service had wide gaps probably due to missing runs (the headway doubles from 9 to 18 minutes). In the September schedules this was corrected.

However, an irregular headway during the PM peak and early evening remains even in October, and the pattern implies that there are still cancelled trips during this period.

29 Dufferin

On 29 Dufferin, the August schedule included some scheduled gaps that are cancelled runs. In the September schedule, some attempt was made to reduce these gaps by changing times of trips adjacent to the gaps. However, the irregularity caused by overlapping base (29A Princes Gates) and tripper (29C Dufferin Loop) services remains and there are many trips scheduled on very short headways.

35 Jane

35 Jane has been operating on the same schedule since the summer, and that is why only one line appears in the chart below. The pattern is caused by trippers until noon and after 3:30 pm operating a headway that does not blend with the underlying base service. This causes many trips to be scheduled on very short headways, some at the same time.

39 Finch East

Like the Jane bus above, 35 Finch East has had the same schedule since the summer (except for a minor change in the late evening in September). Headways oscillate because of the interleaving tripper and base services at incompatible headways.

41 Keele

41 Keele shows the same type of problem seen above on other routes where the tripper service runs on an imcompatible schedule. In some cases, two buses are scheduled to depart Keele Station at the same time followed by a wide gap. The schedule was changed in September and remains in place (green), but with little effect on the basic pattern.

Gaps of 12 to 15 minutes are built into the schedule at times when service is supposed to be more frequent.

45 Kipling

45 Kipling is a strange case because the erratic service is between the peak periods. The schedule is unchanged since the summer, but the headways oscillate during the offpeak because the 45A Steeles service runs every 12 minutes while the 45B Belfield service runs every 24. This yields 6 minute headways where a 45B comes in between two 45As.

The AM peak period shows an even headway because the 45A and 45B run on blended 26 minute headways yielding a 13 minute service.

52 Lawrence West

52 Lawrence West shows the combined effect of trippers and a branching route with different headways on each leg. The schedule is unchanged from the summer.

60 Steeles West

60 Steeles West has different service levels east and west of Pioneer Village Station. To the east, there were minor changes implemented in September, but on the west the schedule is unchanged since the summer.

Service to the east is erratic in the late evening because the 60A service (Pioneer Village to Finch Stn) does not blend properly with the 60B service (Kipling to Finch Stn).

To the west of Pioneer Village Station, the scheduled service is more regular except for some transitional periods with wider gaps and a few short headways.

63 Ossington & 163 Oakwood

The 63 Ossington route is currently split in two due to construction at Eglinton West Station. Service on the northern part of the route is provided by temporary route 163 Oakwood.

During the summer, cancelled runs on 63 Ossington led to headways swinging back and forth between five and ten minutes during the midday and PM peak, and with wider swings in the evening. This was changed in September to the much better-behaved headways shown in green below.

Similarly the 163 Oakwood bus had irregular peak period service due to cancelled runs in August, but this was changed in September.

75 Sherbourne

75 Sherbourne shows the same pattern as 63 Ossington with oscillating headways in the peak periods due to cancelled runs.

(Readers of my Twitter feed may recognize that 15 minute gap northbound just after 3 PM (August, blue) which prompted complaints to @TTChelps from a rider some time ago and piqued my curiosity about this route.)

84 Sheppard West

84 Sheppard operates at a consistent headway on the 84A Weston Road service, but its branches to Arrow Road and Oakdale Road operate on headways that do not blend with the Weston Road service particularly in the AM peak.

86 Scarborough

86 Scarborough operated with the August timetable through to Thanksgiving weekend when it was substantially changed as part of the BRT implementation on Eglinton and Kingston Road.

However, even with the new schedule, headways are uneven because of the different headways on this branching route.

The presence of trippers is evident in the August-September pattern (red). Peak service is less frequent now on route 86 because it is supplemented by the 986 Scarborough Express.

89 Weston

89 Weston shows the effect of cancelled runs, particularly in the August schedules. In September some trips were adjusted to shave off the very high gaps (22 minutes) in the scheduled service, but the line is still not operating at a uniform headway.

102 Markham Road

The schedule for 102 Markham Road is unchanged since August, and shows the effect of trippers scheduled at headways that do not blend. Many trips operate on very short or even zero headways.

116 Morningside

Two changes are evident in the scheduled service for 116 Morningside. In August (blue) there are some wide gaps probably from cancelled runs. These are smoothed out in September (red).

In October, with the implementation of the BRT corridor, the headways stay the same with minor adjustments because the number of vehicles needed to provide this service dropped. For part of its length, the route is also served by the 905 and 986 express buses.

165 Weston Road North

The Weston Road bus shows the now-familiar pattern of trippers running on an unblended headway with some trips being only one minute apart. This schedule has not changed since August.

512 St. Clair

In September, the schedule for 512 St. Clair was changed and this introduced many fluctuations in the scheduled service (red). The change was reversed in October (green) which is the same as the August service.

2 thoughts on “The Problem of Scheduled Service Irregularity

  1. Hi Steve,

    Is there any reason behind having several trips on the 24 bus that goes to Don Mills via Consumers Rd so closely scheduled? I’ve taken the route myself recently and noticed that there is hardly any passenger demand on consumers Rd to warrant one bus, let alone 2-3 more scheduled to be a few minutes behind the first (not including RAD buses).

    Also, how does the TTC manage its rad buses when they are deployed to fill in when a bus is missing on a route? Do these buses follow the schedule of the missing bus, or do they just drive without a schedule and designate their own breaks?

    Steve: The scheduling for some services such as the Consumers Road branch of Victoria Park baffles me. There are problems like this all over the place as I documented in my article.

    As for the RAD buses, I have been trying to get details on how these are used for months, and it’s a big problem because they don’t seem to be tracked reliably, if at all. FWIW the TTC plans to cut back on use of RADs in the new year as service returns more to “normal”.


  2. Regards so many incidents of buses running bumper-to-bumper. I recently observed two freak incidents. 32 Eg West & Jane near Noon. In a span of less than 10 minutes there were SEVEN eastbound buses all in service and twice two pairs went through the same signal without stopping and ZERO passengers! BTW All were in service as I observed their signs.

    Second incident. Runnymede Station likewise around Noon. While waiting on bus platform I observed an Electric bus arrive signed Training Bus. It by-passed the platform to exit. Then a second electric likewise Training Bus. And, a THIRD electric! They followed each other and the bus I boarded was delayed slightly as the 4 of us waited for traffic westbound on Bloor which blocked the sidestreet. (where are those Traffic Wardens?) The bus I was on went north on Runnymede and in the near distance ahead I observed THREE buses bumper-to-bumper!! So, this is how TTC TRAINING teaches their Operators to drive their routes! Ha! Ha! I mean LOL


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