This article is an update to my review of the 903 Express bus that replaced the Scarborough RT. The previous article here: Analysis of 903 STC Express: September-November 2023.

Additions in this round:

• Data for December 2023
• Performance of the 903 service to Centennial College east of STC (Scarborough Town Centre)
• Travel times between STC and Ellesmere & Midland
• A review of terminal layover times at Kennedy Station
• The screenlines for arrivals and departures at Kennedy Station have been moved from Eglinton at Midland and at Kennedy to points on Eglinton just east and west of the loop entrances. This ensures that any delays at the intersections are counted in travel time, not in terminal time. The change has been applied retroactively to charts for September through November.

Correction: References to a 934 Progress Express should have been to route 913. This has been corrected. Thanks to a reader for pointing out this gaffe.

Route History

The 903 Express replaced the Scarborough RT between Kennedy and Scarborough Town Centre Stations. In mid-November it was extended east replacing the 934 913 Progress Express to Centennial College.

The route has taken two separate routes over past months, and a proposed busway in the former SRT corridor is now in the design stage. (This will be the subject of a separate article.)

Since mid November, the eastern terminus shifted to Centennial College with the 903 express replacing the former 934 913 Progress service. The combination of this extension and the distribution of service westbound from STC among many routes means that 903 buses come much less often and on much less reliable headways.

The changes bring problems for riders at both STC and Kennedy Stations who formerly had one, frequent route and now have multiple routes loading in separate areas. Each is much less frequent than the former 903 service and less reliable. For riders who could take any bus between these points, the challenge is to guess which route they should try for rather than having a common loading point with a bus every few minutes.

Travel Time Between Scarborough Town Centre and Kennedy Station

For these charts the screenlines are at:

• Borough Drive & Triton Road, aka “STC West” on the charts. This is the western end of the loop and approach at Scarborough Town Centre, and is a location common to 903 operations either via Progress or via Ellesmere.
• Kennedy Station.
  • For south/westbound trips, the screenline is just east of the GO corridor.
  • For north/eastbound trips, the screenline is just west of the Kennedy Station loop entrance roadways.

I have included the detailed scatter charts of travel times to illustrate both the typical range of values and the degree to which data on specific days can differ quite substantially from this. In September there were a few days where travel times ranged much higher than normal, and these charts are scaled at 60 minutes simply to fit in all of the values. Those peaks show up on the charts of averages and standard deviations, but because these are grouped on a weekly basis, a very large set of outliers on one day is less pronounced when five days’ data are considered together.

(Week 1 has no data because this is before the Labour Day weekend when the 903 buses became trackable.)

Through succeeding months, as the red lanes are installed, the average lines become flatter and drop slightly, but the individual values are still spread over a 5-10 minute range. The transit priority changes were completed on November 19, and December shows a full month with them in place. How much of this is a seasonal lull, or a permanent improvement, will be seen when data for a few more months are available.

September

October

November

December

Travel Time Between Kennedy Station and Midland/Ellesmere

Any consideration of relocating the 903 and other SRT replacement services via the proposed SRT busway can only anticipate savings for the north-south leg of the journey and for access time at Kennedy Station.

The charts below show the travel times between Ellesmere and Kennedy Station via Kennedy northbound and via Midland southbound for November and December. The values vary little over the day, and individual trips lie in a band from roughly 5 to 10 minutes concentrated around the average (the standard deviation is about 1 minute).

This indicates that any substantial time saving via the busway will depend on higher average speeds than are possible on Midland and Kennedy. The distance is four kilometres, and so the range of times shown on charts below translate to:

• 6 minute trip = 40 km/hr.
• 8 minute trip = 30 km/hr.
• 10 minute trip = 24 km/hr.

Any new route must not only provide a higher average speed, but also reduce the variation in trip time so that few if any data points remain at the upper (slower) level.

It is self-evident that the margin for time saving is small, and the primary effect of the bus lanes will be to insulate the route from increasing travel times, congestion and construction effects particularly with SSE work on the eastern approach to Kennedy Station.

December 2023 Travel Time Projections

The estimated travel time from STC to Kennedy for the September configuration was 18-25 minutes. Note that this includes the access times at both ends compared to the charted values shown earlier where the screenlines are outside of the stations to capture only travel time, not any extraneous movement within the terminals.

Allowing for this, the 18-25 minute value is in the same range as shown in my charts except for cases where service was badly disrupted. (One might wryly ask how many of the delays in early months was due to red lane installation work.)

The estimated travel time in the November configuration is 17-22 minutes. Again, this roughly aligns with the data shown above, although if anything, December exceeded the projections with lower numbers.

Operations via the busway are projected to be a flat 15 minutes with much less variation.

Note that part of the time saving relative to SRT operation and the early days of 903 buses comes from elimination of the transfer connection at STC.

Terminal Times at Kennedy Station

The times shown here measure travel from the screenline east of the station (roughly at the GO corridor), through the station, and out again to the screenline west of the point where the station roadways join Eglinton Avenue.

Quartile charts are used to illustrate the range of the data points because in early months these are scattered over the entire page and show no pattern. Note that the scale on the quartile charts is 60 minutes to fit in the range of data values, while on the weekday stats chart the upper bound is 30 minutes.

September saw many buses operated, but on an ad hoc basis. Many of them sat for extended periods, up to an hour, at Kennedy Station. Some data points are close to zero indicating that a bus simply drove past the station on Eglinton and returned northbound. There are few of these, but they push the 100th percentile line down close to zero.

Week 1 of October continued the operating practices of September, but these changed after Thanksgiving weekend. The result is that data for Weeks 2-5 are much better behaved with lower averages and standard deviations. Note how the middle quartiles (green and blue boxes) are very compact. The range of the “whiskers” for the outlying quartiles comes mainly from Week 1 data.

November shows an abrupt jump in terminal times in weeks 4 and 5. This comes from the full implementation of transit priority and the shift to the route via Ellesmere. Buses make the trip faster, and have longer terminal layovers as a result.

December echoes the results shown in late November. Even allowing for access times, the average terminal time is excessive.

Headway Reliability at Kennedy Station Northbound

Service design on the 903 Express changed fundamentally in mid-November when many other routes were extended to Kennedy Station replacing much service formerly provided by the 903.

September and October

In September and October, the scheduled service is very frequent and it is inevitable with very short headways that the standard deviation and average values will be close together. Even so, there are some outliers in the values with gaps of over 10 minutes.

November

November is a transitional month, and the quartile charts below reflect “before” and “after” conditions. The difference in scheduled service level is obvious in the weekly stats chart on the left.

Note that the central blocks in the quartile chart (25th to 75th percentile) are wider in Week 4, not just shifted upward, and the tails for low and high values have also grown. This shows that at a headway more like a “normal” route (8-12 minutes), the 903 behaves like most routes with less reliable service.

December

December continues the pattern from late November. Although the average lines are well behaved, the standard deviations have pushed upward along with the distribution of headways shown in the quartiles.

Headway Reliability at STC Westbound

Headways leaving STC westbound echo the pattern of service northbound from Kennedy Station. However, the middle percentile boxes following the November route change are noticeably wider. This is not just a case of a new schedule, but of the extension of the 903 express to replace the 934 913 Progress Express. STC is now a mid-route stop, not a terminal, and is subject to whatever traffic and other factors affect operations east of STC.

September and October

November

December

Headway Reliability at STC Eastbound

These charts show the headway leaving STC eastbound toward Centennial College. The standard deviations of headways are high at 4-5 minutes, and the quartiles show a wide range of values. This is typical of service with bunching and gaps.

Headway Reliability at Markham Road Westbound

Compared to the headways eastbound from STC above, the numbers are better behaved westbound at Markham Road near the Centennial College terminus. SD values are lower, and the central quartiles are not as badly spread out. Even so there are some very wide and very short headways.