Analysis of 512 St. Clair Operations for July 2010 — Part III (Headways)

In two previous articles, I have reviewed the St. Clair car during its first month of operation on the new right-of-way over the complete route from Yonge to Keele.  Running times during busy periods are down compared with April 2007, when the only right-of-way was between Bathurst and Yonge Streets.  However, the situation with headways, an important factor in how riders perceive service quality, is quite another matter.

For the entire period of construction, the idea of regular, scheduled service was something of a fairy tale on St. Clair, and both the streetcars and buses made their way such as they could along the route.  One would commonly see vehicles taking long terminal layovers, and headways were not a big priority.

In analyses of other routes, there is a common factor that is independent of the route’s length, the time of the year, the weather, eclipses or any other phenomena:  vehicles do not leave terminals on a regular spacing.  They leave when they get around to it, a practice abetted by the TTC’s standard that ±3 minutes is considered to be “on time”.  Pairs of vehicles can travel together on routes with short headways and remain within this standard.

Here are a few samples of headway data for the month of July 2010.

2010.07 Headways Westbound from St. Clair Stn.

2010.07 Headways Westbound from Bathurst

2010.07 Headways Eastbound from Keele

2010.07 Headways Eastbound from Dufferin

2010.07 Headways Eastbound from Tweedsmuir

These charts are in the same format as the link times presented in the previous article.  Data for each weekday are grouped onto four pages in each set, followed by a page with all of the weekdays.  The purpose of this is to show the individual data with trendlines for the days, as well as the “cloud” of data points for the entire month.

Weekend days are shown separately because they run on different schedules.  Note that streetcar service did not run to the west end of the line on all weekend days due to street festivals.

The times shown for St. Clair Station are after any layover the cars may have taken.  These charts show that although the headways trend at roughly the scheduled levels, there is a considerable variation from car to car.  Although this display shows headways rather than schedule variation, it is self evident that it would be impossible for service that was actually on time to exhibit such a spread in headways.

When the service starts off from the terminal running ragged headways, it is inevitable that this will persist across the route unless there is active intervention by route management.  Things have improved slightly by the time the service reaches Bathurst westbound, but the weekday “cloud” still lies mainly in a band between 0 and 10 minutes.

Eastbound, service crosses Keele Street on headways as scattered as at Yonge, and on Saturdays with particular irregular spacing.  Things have improved somewhat by the time we reach Dufferin, possibly due to having passed both the crew relief point and the Route Supervisor at Lansdowne.  Again, however, “better” is only a matter of degree and there is quite a mixture of short and long headways.  By the time cars reach Tweedsmuir (east of St. Clair Station), the headway cloud has spread out again in the typical pattern that cars carrying gaps fall further behind as they cross their routes.

I have not bothered to include comparative charts for April 2007 here as they are much the same, and you can review them in the earlier article on that period’s operation.  If anything, the problem of irregular headways appears to be slightly worse in 2010 than it was in 2007.  This could be a question of less rigourous operating procedures, or that comfortable running and little traffic interference encourage leisurely breaks that can easily be made up within the scheduled trip times.

Another way of looking at the headway data is to view the spread of values.

2010 vs 2007 Headway Spread Westbound fromYonge

2010 vs 2007 Headway Spread Eastbound from Keele

These charts are not intended to be used to read individual data points, but to give an overall impression of what is happening.

Each cluster of vertical lines represents one day’s data broken into individual hours.  These come from the same data that generates the daily headway graphs.  The small dots (seen more easily if you magnify the PDF) are the average values for the hour, and the bars show the maximum and minimum values within that hour.  The longer the bars, the more spread out are the data values within one hour.  The many lines extending above the 10 minute scale show that waits considerably longer than the advertised headway are not uncommon, and the same periods also see some very closely spaced cars.

I am sure that someone will ask about Standard Deviations, and, yes, I did produce a bunch of plots to see how those numbers behaved.  I have not included the charts because they are a bit messy thanks to the comparatively low value of “n” for each hourly period on each day.  What is quite consistent, however, is that the values lie mainly in a band from 2 to 4 minutes.  The 2007 data are actually better behaved than the 2010 data, and this is consistent with my other observations.

If there is a lesson to be learned about managing service on a line with little interference from traffic and generous provisions for recovery time at terminals, it is that headway management is even more important here than on routes where the rigours of traffic congestion and quick turnarounds are the norm.

In the final article of this series, I will examine a few days in detail to show examples both of ordinary operation and of the upheavals caused by external events.

19 thoughts on “Analysis of 512 St. Clair Operations for July 2010 — Part III (Headways)

  1. Plus minus 3 minutes??? This demonstrates a lack of management at the the TTC. Speaking of management, why has the numbers of those on the management payroll at the TTC ballooned since the 1970s and has that rate of employee exceeded ridership growth?

    Steve: Two points. First there has to be some leeway because it is impossible to be exactly on time with the vagaries of stop service times and traffic lights. Having said that, there is little excuse for this sort of headway behaviour at terminals where vehicles have goodly layovers. Moreover, it is clear that a lot of the service does not manage to even stay within 3 minutes of headway (and by implication of schedule).

    As for TTC staff counts, this issue is in the wrong thread. I have addressed it before elsewhere and, for operators, an important part of the problem is the change in labour legislation related to the length of time people who drive public vehicles can work. Yes, there are other improvements — scheduled coffee breaks are one — that came from labour negotiations. On the management side, the number of people looking after routes actually fell for a period when it was thought that fewer people sitting at computer monitors could do the job. This didn’t work, and the TTC had plans to beef up the on-street staff again. Whether this will be completely fleshed out remains to be seen in our new budgeting era. Whether these supervisors are well deployed, and whether they have the tools they need, are separate issues.


  2. Steve, I live on St. Clair and take the streetcar everyday. I feel like the last 3 months I am waiting forever for the streetcar and it inevitably shows up in a pack. However, I seldom see any active intervention by supervisors. Firstly, what tools does a supervisor have to rectify service irregularities? Secondly, what is the route to being a supervisor? I mean is there formal training or at least an established set of procedures?

    Finally, do supervisors actually just use a book to track car locations? Do they not have a tablet or blackberry or something that would allow them to instantly locate a specific vehicle, its average speed, headway etc overlain on a map so that they can actually visualize the state of service.

    Steve: There has been talk of giving supervisors handheld units, but I have yet to see anybody with one in service. Of course, the TTC talked about this as a purpose-built box just before Apple announced the iPad. Why they don’t just provide wireless access to an internal website with all the info a supervisor would need, I do not know.

    As for training and selection, a lot depends on who wants the job because moving out of the union exposes one to all sorts of overtime requirements, a possible net loss of pay and loss of the ability to select one’s own work. Some folks turn down the job. Training depends a lot on who passes on the techniques, such as they exist, for managing routes.

    Thanks, Jamie


  3. This comment is similar to my earlier one on the earlier thread. There is too much data in these graphs to separate the forest from the trees. But of course I am very alarmed by your statement: “If anything, the problem of irregular headways appears to be slightly worse in 2010 than it was in 2007”. I view this as a very important problem requiring work and resources to improve.

    I still think we need a simple headway performance metric averaged on a monthly basis and averaged across the length of the line to aid in public communication and advocacy: eg % headways below 5 mins during peak times (scheduled 3-3.5 mins) , below 10 mins during daytime/early evening (scheduled 6 mins) and below 15mins during late nite (scheduled 9 mins). And analogously for weekends. So there would be three metrics–Weekdays, Sat, Sun.

    And ideally this would be calculated routinely every month by staff and presented to TTC management. And then once it is being tracked, hopefully we would see gradual improvement in the metric.

    I’m sure that all TTC commissioners would be on our side on this issue. How do we make it happen?

    Steve: By the time something like this is generated for over 100 routes (even for the 50 or so major ones), that’s a lot of data. It’s also important to look at various points on a line, not just one location. Sorry that there is so much data, but you don’t see what’s happening without this level of detail. This sort of thing should not depend on a Commission report that will be reduced to simplified averages, but on having staff who take the time to look at details like this (and believe me, there is far more than I have published) to identify places where there are consistent problems.

    I have tried a headway distribution graph, and it just doesn’t have the same effect. More to the point, we must first get the TTC to accept that it is the headway, not the schedule, that riders on “frequent” routes care about. Measure “quality” as seen by the customers, not as seen by management.


  4. Here is a good opportunity for Karen Stintz to show what she can do. This needs to become a priority. It is a small enough route on its own right-of-way that it should be possible to manage it properly. If not, then there is no hope for longer lines such as Queen.

    Steve: The problem here is that she might have to distinguish between problems of having a line with “David Miller” stamped on every inch of the route and of having staff who seem unwilling to address problems of line management.


  5. It seems like a lot of the bunching and gap problems originate from uneven terminal departures; if even spacing of vehicles at the beginning of each run were made a priority (with step-back operators and active management, where possible), on-street service would improve. Two questions about how to achieve this occur to me:

    First, I think you’ve written about how peak subway service is managed to maintain headways as evenly as possible, in order to operate at maximum capacity. Could the TTC take some practices and supervisors from subway management and apply them to the surface routes with rights-of-way or long routes?

    Steve: The real irony is that streetcar operations is under the same manager as the subway with the hope that some of the practices can be transferred, but it’s a long uphill battle. Oddly enough, there were plans to use subway-type dispatching on the Transit City lines to manage headways.

    Second, and this is not so much a “solution” as a happenstance, but will the new streetcars (doggedly assuming they’re still on order) force the TTC to work actively to keep a maximum of one vehicle sitting at a terminal at any given time, at least for the terminals that have not-so-long loops?

    Steve: The problem at terminals comes from an ongoing reaction by TTC to operational problems of stretching running times. This is the catch-all solution. Operators deserve breaks, but by analogy to the subway, you don’t need to waste equipment (and space at terminals). The problem is that until we figure out a way to manage surface lines to a headway rather than strictly to a schedule, we won’t be able to adjust to changes in street conditions by stretching or shortening headways on the fly.

    On the subway, there is less variation in trip times, but terminal queuing still occurs when trains have more time than they need. Most people don’t see the queue because it’s in the tunnel waiting to get into the terminal station, but riders condemned to spend ten minutes or more creeping their way between the last few stations are not amused.


  6. Steve

    May I say once again that your efforts and analysis of the bus and streetcar data on various Toronto routes is very appreciated.

    Not only have you managed to make some sense of a very complicated and challenging subject (line management) you have given some excellent visual data explaining the details.

    The only problem is that the data and the explanation are not linked.

    To give you an example, I’m imagining you as my transit commentator, hearing you explaining what the wiggles and flat lines actually mean. Since you don’t have video with a telestrator showing what is happening, I just print out the chart and read along, circling the “interesting” bits with a pen.

    My question is, can you organize a short “course” on line management that would explain how the various charts (vehicle movement, link times and headway spread) actually explain what is happening to a bus or streetcar route.

    Even a short lesson (written or ‘video’) with some visual elements would be very helpful – even something as simple as having visual screenshots or captures of the graphs, with small circles or marks to indicate the “good”, “bad” and “interesting” examples of line management (like the short turn after 6:00 am at Tweedsmuir, or the strange 30 minute headways in the headway spread chart).

    One of the projects I worked on while I was in Malaysia was to encourage teachers to use visual and audio programmes for lessons and marking. For example, I would use VTute to record my voice while marking aloud, and “Snag It” to capture my actual editing marks, circles, underlines, question marks, etc.

    My students said that it was a great way to interact with the teacher and it freed them from the need to follow “office hours” in order to interact with me and get feedback and assessment.

    The reason why I suggest this is because I think that more of us need to get a better understanding of line management.

    The way I see it, line management appears to be very complicated and therefore, very hard to explain to the average public transport user, enthusiast or planner – or TTC Chair for that matter – to understand.

    I would like to see this change, and therefore, I do hope that you can find a few ways to include visual examples in your very detailed explanations of line management.

    Regards, Moaz Yusuf Ahmad


  7. They leave when they get around to it, a practice abetted by the TTC’s standard that ±3 minutes is considered to be “on time”.

    I think one needs to be careful here. While the ±3 minutes is probably too broad a limit, I have noticed that quite often a streetcar (or bus) will be about to start off, then stop and wait for someone who is hurrying to catch it.

    If the ‘slack’ in the schedule is too low, the drivers will have to pull out exactly on time, whether someone is running to catch it or not. I think that this will likely alienate a lot of riders (and, of course, many will be the same ones who complain about the slightest gap in service).

    I must say that I have found the willingness (and ability) of drivers to wait for me when I am running for the bus to make riding more pleasant. A balance needs to be maintained between allowing some flexibility and maintaining an exact headway.


  8. DavidH, I agree that it’s no fun having operators blow you off at a stop as you’ve almost run up to the front doors.

    That being said:

    1) I’ve been on runs which always run to schedule, yet the operator is quite kind to late arrivees. I’ve also been on horrible runs which are behind schedule, the operator is barely nudging the bus or streetcar above 20 km/h, yet they blow off people who are knocking on the doors. I don’t have good statistical evidence, but I would propose that operators who leave way early or late for their own reasons have little interest in accommodating the needs of passengers. So there may be an inverse correlation between variance from schedule and picking up latecomers.

    2) At some stops you simply have to close the doors and proceed, or you’ll be there all day picking up one straggler after another.

    3) If the route ran reliably and on time, with regular and tolerably short headways, people would be less inclined to run (sometimes quite dangerously) for the closing doors. On the other hand, I’ll run like an idiot for the 501 LONG BRANCH car because I have no idea how long I’ll have to wait for the next one.


  9. “Of course, the TTC talked about this as a purpose-built box just before Apple announced the iPad.”

    Too late now: I am afraid to contemplate what will happen if anyone mentions buying iPads for TTC workers in front of Rob Ford. (Even though it *would* in fact be cheaper than purpose-built hardware.)


  10. Personally I think any modern internet-ready phone with a decent-sized screen would be sufficient. How much info is needed?

    Steve: You need a map big enough to see the entire route as well as information about things like pending crew changes, a notepad to keep track of things like short turns, and a keyboard (or equivalent) that someone can operate standing on a street corner in February without losing their fingers to frostbite.


  11. There is absolutely no reason why vehicles should be leaving the terminals in bunches. One problem may be that the TTC’s practice of adding “recovery time” to the schedules becomes, to the operators, a de facto “layover” whether they arrive late at the terminal or not. This is only my suspicion and I don’t have any proof of this, so if it’s not true then I apologize to the operators. However, presumably the operators have a specific time that they are to leave the terminals, and I’m quite sure that it isn’t the same time for successive runs. So when two or three vehicles leave at the same time, we can be sure that at least one or two of them are not on time. Similarly, departure from the terminals should be one of the easiest things for the supervisors to track and manage — they don’t need an iPad or any fancy technology, they just need to be standing there with a printed schedule of departure times for each run.

    Steve: I think that the generous running times actually encourage irregular headways because there is an assumption that operators can always get back on time. Of course the odd one may be hoping to be so late that they are short turned and get another siesta.


  12. I daresay that the number of TTC non-union employees has not remained in a constant state of unrestrained growth since the 1970’s. In fact, I recall during David Gunn’s tenure in the 1990’s that there were non-union staff layoffs of about 1500 people. I knew a couple of staffers at the time who had upwards of 25 yrs of service who got laid off, not to mention salary cuts due to the social contract and then a freeze until the early 2000’s. Also, the TTC has increased its overall ridership (in spite of itself) to record levels. You also have to differentiate route management staff with other non-union staff such as those hired to implement subway and LRT expansion. I’m not defending everything about the TTC here, but the tendency to oversimplify questions about staffing (a la certain right-wing commentators) can lead to unfair and inaccurate conclusions.


  13. Ed says: “If the route ran reliably and on time, with regular and tolerably short headways, people would be less inclined to run.” This is very true, I used to live in Montreal and there the subway runs far less often so there is a great deal of running in subway stations. Here the subway has excellent headways and one really seldom sees anyone running.


  14. This needs to be turned into a pilot project for line management. There needs to be a supervisor on duty, on site, to oversee operations. Instructions need to go into effect that the end terminals plus St.Clair West are to be timing points and no car is to leave these points ahead of time. Not 3 minutes, not 30 seconds. From there close attention needs to be paid to what is happening along the line. Any car that is late, the operator is to questioned as to the cause and any remedy sought. If they cannot manage this little line then, there is no hope for anything else. If they do get it right, carry on to another car line.


  15. I agree. Why can’t there be line management similar to what is done on the subway? If that sort of line management was implemented our streetcar system would run alot smoother. Any idea why something like this was not implemented already Steve?

    Steve: There are limits to what can be done on the surface, and running times are a lot less predictable (as we will see in a forthcoming series on the Carlton car). All the same, problems with uneven departures and with cars running nose to tail, even after they have been short turned in an attempt to space service, really need to be dealt with.


  16. ±3 minutes! How long does it take to cycle through a set of traffic lights? 1 to 3 minutes? How many traffic lights are there on St. Clair? Are the traffic lights actually connected with TTC control like the signals in the heavy rail subway? Probably not. There is still not real transit priority on St. Clair, else the streetcars would be given first go instead of the left turn automobiles. Unfortunately, the traffic lights are not under the control of the TTC, but the roads department, so the streetcars will continue to be held back.

    Steve: The typical cycle time is 80 seconds. On suburban intersections, it is usually longer in part because of the wider streets.


  17. Two questions come to mind when I think of the three year nightmare that was the St Clair streetcar construction: why didn’t take the opportunity to widen St Clair west of Keele and add tracks and secondly, since St. Clair West Station was under construction for several months, why didn’t they take the time to make it accessible (elevators)?

    Steve: Originally, a study of extending the St. Clair line to Jane was supposed to be done, and provision made for this in the roadwork. However, the death (or very deep sleep) of Transit City and the anti-streetcar attitude of the current administration has put all of this on hold.


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