From October 20 to 30, Metrolinx will host a series of public meetings for those interested in commenting on the draft Regional Transportation Plan. Four background papers are now available on the RTP page providing additional information about various aspects of the plan:
- Climate Change and Energy Conservation
- Transit Technologies
- Modelling Methodology and Results
- Mobility Hubs
This article deals primarily with the modelling of ridership, likely the most important of the four backgrounders because it shows how the proposed network is hoped to behave and the impact it will have on travel in the GTAH.
There are many caveats in this process set out in some detail in the report, and I won’t replicate them here beyond the standard warning that any model is only as good as the data it is fed, that the likelihood that the real world will match the modelled one falls off as we move into the future, and the basic fact that models cannot project the effects of changes beyond the range of known circumstances. We know what changes are expected in population, jobs and housing fairly well for a 5 to 10 year horizon, but the 25 year view is hazy. We know how people react to comparatively small changes in the relative cost of travel, but we don’t know what happens when changes are large and sudden. Metrolinx is quite open about these problems, as anyone publishing modelled data should be, and it is important that we view the projected network behaviour in this light.
From my own point of view, there is a much more profound problem. The only data shown in the backgrounder are for a completed network of routes in 2031. If anything is certain about Metrolinx, it is that the proposed network will not all be built, and will not be built when or where today’s draft plan suggests. The draft RTP itself acknowledges that this is a conceptual plan and is subject to change.
Moreover, the primary discussion today is about what will be done with the $11.6-billion of MoveOntario money we hope to see from Queen’s Park, plus, if the gods smile on us, an additional $6-million from Ottawa. That’s less than half of the total cost of the RTP, and does not cover any costs for local transit systems such as ongoing maintenance, fleet expansion and service improvements.
Whatever is built, the work will happen in stages. From a simple marketing viewpoint, if nothing else, it would be useful to know what the situation will be in five, ten, fifteen years as new routes come onstream. Will the public (and the politicians who depend on that public for support of large public works like the RTP) see significant change in a meaningful timeframe? What will we have to show for all the money we will spend?
Metrolinx already has a short list of projects to start immediately, in effect a seven-year plan, plus a fifteen-year plan in the RTP. However, the backgrounder only shows the situation on a 25-year horizon.
How much of the demand projected so far in the future comes from existing or soon-to-be trips, and how much depends on building or rebuilding that is decades off? If we only look at the 25-year timeframe, we will see projections skewed by populations and jobs that won’t exist for at least a decade.
How will travel patterns behave when only a third or a half of the network is in place? Will we have temporary crowding problems caused by an inapt (or inept) sequencing of projects?
The second major flaw lies in the presentation of the projected data. The backgrounder gives us figures for the AM peak and the peak point on each line, but does not show the volumes on links within the network or even identify where the peak points are (although in many cases they are easy to guess). Evaluation of proposed routes is difficult if we don’t know the contribution each link makes to the network as a whole, or the impact addition of a new route has on links in the existing system. Decisions about project staging, how much of a new route should be built when, depend on knowing the time periods when each stage would be most effective for the region as a whole.