Route 41 service snapshot - 3 to 30 November
Route 41 is a frequent route that runs from Billings Bridge to St. Laurent. The route is the primary service on Heron Road, Walkley Road, and St. Laurent Boulevard, and services Herongate and Elmvale, both low-income communities with relatively high transit use.
The westbound service towards Billings Bridge is generally reliable, but the eastbound service towards St. Laurent has a severe mismatch between scheduled and actual runtimes, falling below the 5th percentile for much of the day. The usual afternoon peak reliability issues also make an appearance.
Cancellations
Over the snapshot period, 6.0% of Route 41 trips were cancelled. The westbound rate was 6.0%, and the eastbound rate was 6.1%. We will never get route-by-route numbers, but consistent results like this make me wonder about OC Transpo's reported cancellation rates.
Travel Time
The eastbound service is severely underscheduled, with morning-to-midday trips scheduled below the 5th percentile of actual runtimes. Buses arrive at St. Laurent late, and whether they're turning back to Billings Bridge or interlined onto another route, these delays propagate.
What's more, the variability of travel times is quite high, but consistent, throughout the day. Notably, the variation is roughly the same in the PM Peak as the rest of the day, even as travel times increase.
Westbound service is scheduled much more precisely, and the scheduled times roughly match the actual runtimes. The time variation is smaller than the eastbound service, but it grows going into the evening (I suspect, but cannot prove, low data quality).
It's worth noting that the travel times are fairly similar at the same time period, but eastbound service is simply scheduled for much less time than the westbound service.
On-Time Performance
As could be expected from the travel time analysis, westbound punctuality is better than eastbound punctuality.
During the morning peak, around 80% eastbound trips arrive at the terminus late, an on-time performance of just 20%. Westbound service does see growing delays, but they are not as severe, on-time performance falling to around 70%.
In the midday, eastbound reliability continues to be awful, with nearly half of trips running over ten minutes late at St. Laurent. Westbound reliability is much better, running "only" 30% late at Billings Bridge.
The PM Peak is the least reliable period across most of the OC Transpo network. Both the eastbound and westbound services run late , which is inline with this trend.
The eastbound service is the same as ever, low scheduled travel times leading to a high proportion of late trips arriving at St. Laurent. In the westbound direction, things are more interesting - with 20-30% of trips late throughout the route, the problem is not travel time, but that buses bunch with a small (but significant) portion running early, leading to a ~60% on-time performance at the terminus and a bunching spike in the charts.
In the evening period, service falls to half hourly. Eastbound, the same old problems continue - not enough runtime, so on, etc. Westbound, there are a small proportion of trips that start delayed and stay that way throughout the route, but no new delays appear.
Punctuality is good on the weekends. There are only minor delays eastbound and no major delays in either direction.
HeadwaysI have changed the format for these charts, so that all charts for each direction of travel have been consolidated into one graphic. This shows the relationship between different points on the line much more clearly and includes higher quality data (less error due to tracking wackiness) also it's much less work.
In the eastbound service, the level of bunching is lower at Heron/Bank than at the other two checkpoints, though the difference is not large.
Despite the inadequate schedules, bunching does not seem to be a large concern going eastbound, outside of the always-troublesome PM Peak. The eastbound service sees only low-to-moderate levels of bunching through the rest of the day. However, high rates of bunching and cancellations at the busiest period, the PM Peak, help contribute to the perception that OC Transpo is unreliable.
Westbound cancellations are less severe in the PM Peak, with a smaller headway spike. There is, however, a larger gap between Walkley/Halifax and Heron/Bank, suggesting that buses bunch eastbound along Heron Road.
String ChartsThe PDF for full charts from week 3, from 17 to 21 November, can be found at this link.
As an exemplar, I have pulled the string diagrams from Wednesday, 19 November for this post.
The two most notable chokepoints on the route are the approaches to the intersection at Bank/Heron in both directions, including the eastbound left turn onto Heron; and the section of St. Laurent between Elmvale and Belfast, though it's not clear whether some of this is from buses sitting at the Elmvale stop itself.
Notably, despite the removal of the eastbound slip lane on Heron during the current Bank Street Renewal project and replacement with a regular right-turn lane, there are no plans for any kind of transit priority here.
More minor slowdowns can be intermittently observed wherever there are left turns, most notably at Russell and Walkley going eastbound, and Russell/Southvale going westbound. This is a problem of route design, but in this context, more turns is a tradeoff between vehicle speed and walking distance.
