In the previous article, I reviewed travel times on 505 Dundas for the month of April 2024. Now, here are charts of the headway data.

Service on this route comes nowhere near meeting the TTC’s own rather lax standards for service quality. The TTC measures On Time Performance (“OTP”) with the assumption that if cars are on time, then regular service will take care of itself. However, there is considerable leeway in the words “on time”.

OTP is measured only at terminals and compares the scheduled trip time to the actual one. If a car leaves no more than 1 minute early or 5 minutes late, it is “on time” for the stats. There is no measurement of OTP along the route, and the spacing from terminals is rarely maintained.

The six minute window this provides allows service to be quite erratic, but still counted as “on time”. For example, on a route like Dundas with a 10 minute headway, cars could alternately be 5 minutes late and 1 minute early. This would produce the following departure pattern:

Scheduled	12:00	12:10	12:20	12:30	12:40	12:50	1:00
Actual	12:05	12:09	12:25	12:29	12:45	12:49	1:05
Headway		4′	16′	4′	16′	4′	16′

The cars on short headways would inevitably catch up with the cars on wide headways, and pairs 20′ apart would travel across the route. There is nothing in TTC standards to measure this. and reports will blissfully say that service is “on time”. In fact, the TTC does not even achieve its own lax standard.

There is also no metric for missed trips caused by absent cars. Conversely, a trip at a terminal can legitimately be missing if a car was short-turned to restore regular service. The TTC’s focus on OTP stats to the exclusion of any other metric is one reason for the no short-turn policy. This can do much damage by blocking legitimate service management techniques. In the article on travel times, there are many examples of short turns to preserve service on the central part of the route rather than letting vehicles pile up at terminals.

This article shows how service leaving the terminals of 505 Dundas is disorganized from the outset, and how this evolves along the route. For an organization that hopes to win back riders, this is not an ideal example of what service should look like.

Continue reading →