An Ottawa bypass would compromise the business case of the entire project. Ottawa is highly connected to Toronto and almost as big a destination by rail, road and air as Montreal. I don't know the numbers, but I'd bet that Ottawa Station's Via Rail ridership isn't much lower than that of Montreal Central. Having all trains go through Ottawa not only serves that demand, it also decreases costs by putting all three cities on a single line. A train going through Ottawa without stopping (or bypassing it altogether) turns away half the potential riders to make the ride only slightly faster for the other half. That's an oversimplification, but it illustrates how the cost is higher than any benefit.
To prove your point, some may recall my
post about projecting ridership figures by using a concept called "Generalized Journey Times" from just over a month ago, where I posted these figures:
Table 1: Calculation of change in generalized journey time (GJT) for the Corridor East
Compiled from:
Globe&Mail article (for travel times and frequencies) and
Passenger Demand Forecasting Handbook (for GJT headway values)
Table 2: Approximation of passenger figures for 2030 (after population growth and GJT adjustment)
Note: The respective growth rates for Southwestern Ontario (SWO) are taken from Toronto (CMA) as start of route and Ontario (Province) as end of route.
Compiled from: official VIA Timetable (effective 2019-06-02, for train mileages),
VIA Rail Annual Report 2019 and
Victoria Transport Policy Institute (2018).
Please refer to
my original post for any explanations of the above, but note that I've updated the second table to reflect 2019 rather than 2018 ridership data, which has increased the ridership projection for 2030 from 6.6 million (or
6.1 million using 2017 ridership data) to 6.9 million.
If we now take the assumed hourly HFR service and deviate half of the services over the Bypass around Ottawa, our travel time between Toronto and Montreal decreases by the 15 minutes suggested by
@innsertnamehere, which may increase of the passenger volume between of 5.1%. However, the resulting doubling of the headway offered between Toronto&Ottawa and between Ottawa&Montreal, may
decrease the passenger volumes of these markets by 8.6% and 13.1%, respectively, thus resulting in an overall drop of passenger volume by 4.3%:
Now, one might argue that the Express trains should be offered
in addition to hourly service, but since that extra train could just as well operate via Ottawa (thus doubling the frequency offered for
all three markets), we have to compare this scenario with half-hourly service on the Toronto-Ottawa-Montreal corridor and this results very similar results, with bypassing Ottawa for a 15 minute travel time saving may increase passenger volume between Toronto and Montreal by 4.9%, but may decrease that between Toronto&Ottawa and between Ottawa&Montreal by 4.4% and 6.6%, respectively, thus resulting in an overall drop of passenger volume by 1.4%:
Despite all the significant limitations of my approach (for instance, using "passenger miles" as a metric for passenger growth is particularly awkward when the travel distance between two cities is shortened, which should artificially reduce this metric even if demand itself remains the same), I think this highlights that bypassing a city in pursuit of shorter travel times will probably not pay off if the bypassed city is a major trip generator.
And all of the above is without considering that adding the Ottawa bypass adds 146 km (From De Beaujeu to Smiths Falls via CP's Winchester Sub) to the HFR network length (ignoring the Montreal-Quebec branch), thus increasing the length of ROW to be built or upgraded (which is a major cost driver for capital costs) by one-quarter and that adding an hourly Express train to hourly Toronto-Ottawa-Montreal trains would almost double train-mileage (which is a major cost driver for operating costs):
I can't stress enough that I have neither access to the scenarios studied by the Joint Project Team nor to the assumptions and calculations they use to assess and compare them, but given the clear picture my quick-and-dirty calculations I presented above paint, I would be highly surprised if their (much more refined) models recommended going down the route of building a Ottawa Bypass at the same time as the Toronto-Ottawa-Montreal HFR route...