Updated October 29, 2015 at 7:00 pm: Additional material based on the presentation and debate at the TTC Board meeting has been added at the end of this article.

At its meeting on October 28, 2015, the TTC Board will receive a presentation about bus fleet and garage planning. This combines many threads that have been discussed separately in the past into one overview and co-ordinated long-range planning, something missing from Board-level debates at the TTC for many years.

Four important changes in the TTC’s fleet planning lead to one common goal: an increase in bus reliability.

• Steady-state procurement. TTC bus purchase quantities fluctuated wildly over past decades. In the late 1960s, there was a major system expansion into the suburbs concurrent with the subway extensions to Kennedy and Kipling, and later north to Finch. This produced a big spike in bus purchases which echoed through the system every 18 years or so as this generation of vehicles (and its successors) came due for replacement. Other ebbs and flows arose from political decisions such as service increases beyond “typical” requirements, or service freezes imposed through declining standards. This plays havoc with maintenance planning and with the City’s capital plans.
• Increase the spare ratio. Historically, transit spare ratios have been set at about 12% (even lower values can be found decades ago on the TTC), but this only worked when vehicles were considerably simpler than they are today. It is worth noting that the PCC streetcar was designed from the outset to be a low-maintenance vehicle with roughly a monthly trip into the shops for preventative maintenance. The onset of vehicles with much more complex technology, and especially with technology at the “bleeding edge” of implementation, did nothing to improve transit maintenance costs. Higher spare ratios also require more capital to be tied up in buses under repair. Higher failure rates affect service.
• Early retirement of the hybrid bus fleet. The hybrids were one of those nice “green” ideas where the technology simply did not perform as expected, but for a time government policy forced the TTC into buying nothing else. The fleet is less reliable than the diesels it supplanted, and the extra capital cost is not offset by lower operating cost.
• Re-align diesel bus overhaul schedule. Various subsystems on a bus go through major overhauls or replacement on a planned cycle through the vehicle’s life. The schedule for this work will be adjusted to better match needs and to fit well with a planned 18-year bus lifespan. Equally important will be a change in the approach to routine maintenance with a shift from “fix on fail” that accounts for 80% of work today to a proactive, preventative replacement of parts before their expected in service failure disrupts service.

An additional issue still under study is the question of just how long a bus should stay in service. The 18-year span typical in Toronto (and previously in many other cities) arose from a combination of vehicle quality (the GM New Looks lasted forever) and of limited subsidy funding. However, a longer lifespan demands that transit systems have the capability to perform major overhauls that will keep a bus running that long, and this is not practical for smaller systems. Long ago, the USA standard dropped to 12 years as the funding cycle for federal subsidies to bus purchases. A still unanswered question is whether this should be Toronto’s policy.

Finally, there is the matter of garage space for a fleet that will continue to grow before the combined effect of subway and LRT line openings will see a drop in total fleet requirements.

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