In many past articles, I have reviewed the quality of service on various routes from the point of view of headway regularity, travel times and short turns. While these analyses can show that disordered service is commonplace, they do not address a more basic question: what is the actual capacity of service offered, how consistently does the TTC actually provide room for passengers to ride?
This article uses vehicle tracking data in a different manner.
Service at Bathurst & King picks up almost all transit vehicles in both directions without effects of short turns. However, raw vehicle counts do not directly represent “capacity” because this must be adjusted for vehicle size. For example, twenty streetcars in one hour can carry more passengers than twenty buses. The capacity per hour is affected by the combination of two factors: how many vehicles of each size actually passed the intersection, and how many vehicles even operated in the peak period. The latter factor is important because “missed trips” don’t just arise from erratic service, but also from a failure to field all of the scheduled vehicles.
The following sets of charts show the capacity of service passing Bathurst Street eastbound during the AM peak (0600 to 1000) and westbound during the PM peak (1500 to 1900). Data are shown for all weekdays from September 2013 to July 2016 except for February 2016 (because I do not have data for that month).
There are three types of chart in each set:
- Vehicle counts by type by hour
- Capacity of the vehicles observed by hour
- Total capacity over the four-hour period
Visible in these charts is the fluctuation from time to time in the proportion of service provided with standard CLRV streetcars, articulated ALRV cars, buses and new Flexity LFLRVs (since June 20, 2016). Very low values on individual days correspond to situations where a diversion to much or all of the service away from the intersection, typically to Queen Street. Another factor is that occasionally information for the time in question does not exist in the data provided by the TTC.
Over the length of an hour, a small day-to-day variation might be expected in vehicle counts through minor service irregularity. However, the mix of vehicles affects overall capacity. Late 2014 saw the onset of bus replacements of streetcars, and the drop in streetcar counts came primarily from ALRVs which are much larger vehicles. The number of bus trips required to replace ALRV trips was substantially larger as the charts show. However, there remains a considerable fluctuation from day-to-day in the number of each type of vehicle.
Capacities are calculated from the TTC’s service design values:
- CLRV: 74
- ALRV: 108
- LFLRV: 130
- Bus: 51
Note that vehicles can carry more people than these numbers suggest under crush conditions, but service cannot be designed based on crush loads on every trip.
What is quite striking about the capacity charts is the fluctuation over a range of about 500 passengers per hour, roughly 25% of the typical value, during the busiest periods. In other words, even if the vehicles arrived evenly spaced and, therefore, evenly loaded, there would be a considerable change day-to-day in the quality of service experienced by riders.
This begs the question of whether the days with lower capacity arise from “traffic congestion”, the TTC’s favourite explanation for erratic service, or if another factor could be at work.
Vehicles in Service
Another way to look at the data is to simply count the number of vehicles in service on the route. The next charts report on the number of vehicles of each type observed on the central part of King (Jarvis to Jameson) from 0700 to 0900, and from 1600 to 1800.
What one would expect to see if the schedules are to be believed is that the vehicle counts would stay more or less the same for a series of weeks corresponding to one or more “board periods”, the five-to-six week periods for which set of schedules remains in effect. However, what we see, particularly for streetcar modes, is a substantial change day-to-day in the number of vehicles the TTC actually fielded. The total vehicle count has fluctuated quite a lot (a range of about 10 vehicles on a likely scheduled total in the high 50s in the AM peak).
The numbers here do not translate directly to capacity, but they are linked:
- More streetcars and fewer buses can lead to higher capacity depending on the replacement ratio, but this can be offset by the degree to which larger streetcars (ALRVs) are used.
- Schedule changes to increase running times, even at similar headways, result in more vehicles in service (because the round trip time is longer) but not in more capacity (the vehicles/hour counts are unchanged).
The TTC speaks of the bus trippers on King as “expanding capacity”. As the charts clearly show, they do not achieve this effect because they are only replacing streetcars, and not necessarily on an equal capacity basis. The buses are a response to a shortage of streetcars, not a service improvement, except in the sense that without them the remaining streetcars would be even less able to cope with demand.
One factor which the vehicle-based data cannot reveal is the degree to which runs are cancelled because there are not enough operators available to drive them. This is not just a manpower issue, but one of schedule design and the degree to which all runs are part of regular crews, and how many depend on spare or overtime operators whose availability fluctuates. Trippers that operate for a short period are especially vulnerable to this because they are short pieces of work more likely to be crewed as extras.
The TTC has many challenges on King Street, and the City is now studying ways to redesign the street to aid transit operations, among other goals. However, fielding a consistent level of service is an essential part of delivering a consistent quality to riders on the line, and the TTC does not achieve this.
There has been some growth in capacity of service provided on the central part of the route, notably with the service redesign for 514 Cherry, but how long this will last in an era of trimmed budgets remains to be seen.
The counts and capacities shown here include service on 514 Cherry starting in late June 2016, but do not include service on 508 Lake Shore. This service was suspended due to the streetcar shortage in January 2015 (PM peak), and June 2015 (AM peak). It contributed a small amount of added capacity when it operated, but this was quite erratic because the arrival times and numbers of vehicles assigned varied considerably. I do not have 508 tracking data for many of the months included in these charts, and so have omitted the route from the analysis.