The Reliable Unreliability of TTC Service

In a recent article, I reviewed the TTC’s Service Standards Update. These standards included targets for headway reliability which are extremely generous and allow the TTC to claim that services operate “to standard” when actual rider experience is less than ideal.

Reliability of service is a top concern for TTC riders, and it has also been identified by TTC staff. Where the problem lies is that the targets offer little incentive to improve or measurement of just how bad the situation really is.

When the TTC talks about reliability, they inevitably trot out excuses about traffic congestion and the difficulty of operating service in mixed traffic. This has been a standard response to issues with streetcar routes for as long as I can remember. However, the typical TTC rider is a bus passenger, and this group has flagged service reliability, frequency and crowding as issues just as important as for streetcar riders.

Regular readers will know that over the years I have published many analyses of route performance looking mainly at the streetcar system, but also at selected bus routes. Recently, I decided to expand this to a number of routes in Scarborough where the quality of bus service often comes up in debates about the Scarborough subway extension, and to revisit some of the routes affected by construction on the Spadina extension which has now pretty much wrapped up. Apologies to readers in Etobicoke because this gives a central/eastern slant to the routes reviewed here, but I have no doubt that route behaviour in our western suburb is similar to that on the rest of the network.

This post may give some readers that dreaded sense of “TL;DR” because of the amount of material it contains. It is intended partly as a reference (readers can look at their favourite routes, if present), and partly to establish beyond any doubt the pervasiveness of the problem with headway reliability facing the TTC. This problem exists across the network, and setting performance targets that simply normalize what is already happening is no way to (a) understand the severity of the problem or (b) provide any measurement of improvements, should they be attempted.

The data here are taken from January 2017. The analysis would have been published sooner but for a delay in receiving the data from the TTC, a problem that has now been rectified. As always, thanks to the TTC for providing the raw material for this work.

Although January is a winter month, the level of precipitation, and particularly of snow, was unusually low for Toronto, and so weather delays do not lead to anomalies in the data.

Toronto Precipitation and Temperatures for January 2017

The TTC’s current attitude to service reliability is to focus on conditions at terminals with the premise that if service leaves and arrives on time, then there is a good chance it will also be in good shape along the route. This is a misguided approach on two counts.

First and most important, there is little indication that service from terminals is actually managed to be reliable, and the “targets” in the standards provide a wide margin by which unreliability is considered acceptable. In particular, it is possible for services to leave termini running as bunches of two or more vehicles and still be considered “on target”.

Second, any variability in headway from a terminal will be magnified as buses travel along a route. Buses carrying larger headways (gaps) will have heavier loads and run late while buses closely following will catch up. The result can be pairs of buses operating at twice the advertised headway, and with uneven loads. Without active management of service at points along a route, the problems become worse and worse the further one progresses away from a trip’s origin. Again, the generous standards allow much of this service to be considered acceptable, and so there is no need, on paper, to actually manage what is happening.

TTC operators are a great bunch of people, overall, but the laissez faire attitude to headways allows those who prefer a leisurely trip across their route to run “hot” with impunity. The worst of them are, fortunately for riders, only a small group. The larger problem is the degree to which irregular headways are a normal situation across the system.

The balance of this article looks at several routes primarily for their behaviour near terminals as this matches the point where the TTC sets its targets, such as they are. To recap the Service Standards:

The TTC standards vary for very frequent (less than 5′), frequent (5′ to 10′) and infrequent (above 10′) services.

  • Very frequent services target a band of ±75% of the scheduled headway.
  • Frequent services target a band of ±50% of the scheduled headway.
  • Infrequent service aims for a range of 1 minute early to 5 minutes late.

The charts which follow look at actual headways, not scheduled values, and it is clear throughout that the typical range of values exceeds these standards.

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6 Bay and 94 Wellesley Service Analysis for January 2016 (Part II)

In previous articles, I reviewed the operation of 6 Bay and 94 Wellesley for the month of January 2016. This post updates that review with a different way of looking at headway statistics over the route and by time of day. The new chart format consolidates information previously shown only in separate chart sets.

In earlier analyses, I presented information for headways (the time interval between vehicles) at a point over a month in charts like this:

6 Bay Headways at Charles St. Southbound

This set of charts includes several pages of detail showing individual vehicle headways, day-by-day, with statistics for the entire month at the end. This is useful for looking at behaviour at a point, but another way to summarize the data is to bring the stats for all timepoints on the route onto a single set of charts.

The new charts use the data shown on the weekday, Saturday and Sunday statistics pages from each timepoint set (such as the one linked above) and merge them on a single chart for each direction and type of day.



On each chart, the average headways are shown as solid lines while the standard deviation values are dotted and use a lighter version of the same colour as the corresponding averages.

The first page for 6 Bay shows weekday statistics from the south end of the route at Jarvis & Queens Quay to the north end at Bedford & Davenport. The line for Bedford (purple) breaks away from the other values because half of the service is scheduled to short turn at Yorkville during the peak periods. Generally speaking, the averages for each timepoint will stay close to each other except during transitional periods between service levels (the change does not necessarily complete within the same hour over the entire route) and in the case of major disruptions or diversions.

What the charts show, however, is the magnitude and evolution of the standard deviation in headways along the route. This is a value that measures the degree to which data values are close to or scattered around the average value. If the SD is low, then most of the individual values are close to the average, and therefore the headways are all close to the average value. If the SD is high, then headways are erratic. The average may be well-behaved and fit the schedule, but times between individual vehicles can vary considerably. Typically, about 2/3 of the data points will lie within one SD either way of the average. Therefore, if the average is 5 minutes, and the SD is 8 minutes, 2/3 of the data points lie between 2 and 8 minutes. The rest are beyond this range.

This has some relation to the TTC’s own goals for headway reliability. Until fairly recently, vehicles were considered to be “on time” if they were within 3 minutes of their scheduled time. On occasion, the TTC would report this value relative to scheduled headway, rather than to the timetable, to acknowledge that riders care more about reliability than the “on time performance” of individual vehicles. This measure has been replaced with a new target in which vehicles should leave terminals no more than 1 minute early and no more than 5 minutes late. This is ostensibly the same 6 minute window, but with three important differences:

  • The measure is always to timetable values, not to headways. Service can be operating on a regular spacing, but be off schedule, and therefore rank poorly. However, “on time” performance is a TTC goal because it minimizes overtime payments.
  • The measure is only at the terminal point on the assumption that if service begins its trip in good shape, this guarantees reliable service further down the line.
  • Measurement at the terminal will expose excessive short turning because vehicles that do not reach the terminal cannot be counted as part of the “on time” metric.

This sounds good in theory, but the idea runs aground on two important factors.

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Analysis of Service on Route 6 Bay Bus for January 2016

In previous articles reviewing the quality of service on various routes, I have concentrated on long, major lines such as Queen, Dufferin, Finch West and Lawrence East. However, a review of a few shorter routes has been on my “to do” list for a while because the problems that beset longer routes should not be present.

This brings me to routes 6 Bay and 94 Wellesley (the subject of a future article). Both of these routes are quite short, and they operate in the “old” city of Toronto mostly south of Bloor Street.

6 Bay went through the travails of construction at Union Station and, to a lesser extent, on Queens Quay, but that is now finished. 94 Wellesley didn’t have construction to deal with, but until September 2015, it had an old schedule which the bus operators could not meet.

How are these routes running today?

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