What about relieving Pearson/avoiding building Pickering? It would also help tourism by bundling Montreal and Toronto.
TC estimates that a reliever would not be needed till at least the mid-2020s. Building the Pickering airport would result in the re-location and consolidation of traffic from City Centre, Markham and Oshawa, the reduction of some traffic at Buttonville. The price tag of $2 billion is relatively cheap compared to any proposed HSR and would probably be recovered through airport fees.
I could see a benefit to tourism though since HSR travel might be cheaper than commercial air. But even this is a specious argument. Air travel in Canada is expensive because of prohibitive government fees. Canada is the only country in the developed world that extracts revenue from its airports instead of spending on them. If the federal government merely stopped collecting rent, air travel would become significantly cheaper.
That would be one benefit. Before recent reductions in air traffic, the high rate of growth in air traffic - has created a crowded sky's (limited routes, traffic closer together, etc.). When I was flying to Toledo - 15 years ago (don't ever want to go to that city again), the proximity alarm in the cockpit was almost constantly going off (closer to Detroit). One of the goals should be to remove all short-haul traffic from the Montreal/Toronto/Ottawa and even Kingston - from the airports -- opening up those slots for long-haul travel. There is a lot of business travel between these cities - where people are traveling for a meeting and want to go there and return the same day. Rail would make it more efficient - in fact if it is a half-day meeting - you could return in the afternoon.
Having operated in the Toronto Terminal Area, I can tell you that, while it's crowded, it's nowhere close to the level of proximity alarms engaging on a regular basis....which brings to mind the question of what the heck was going on Toledo that the TCAS was going off as often as you say it was? That's pretty serious business.
Another significant question here is...what's so bad about the skies filling up? Competition for slots will actually improve the efficiency of the system by forcing airlines to use bigger aircraft. Air Canada has over two dozen departures a day from Toronto to Montreal alone, most of them on A319s and A320s sitting 120 and 140 pax respectively. Fewer slots would actually prompt AC to use larger aircraft as traffic increased for that city-pair.
^^^
I think HSR can be justified to improve connectivity between MTL-OTT-TOR, though the Windsor & QC branches are probably not necessary at first. A few things would have to happen before this is practical though. Firstly, gas prices will have to continue to climb above wage increases. Recent set backs aside, I think most people are still bullish on the long term price of gas. In other words, I would be surprised if oil was 60$/B in 2030 (adjusted for inflation). We saw earlier in this summer how poorly the airlines were able to cope with rising gas prices. Given the industries absurdly low margins (really, I don't even know why people invest in airlines...), it would have a tough time if gas prices started to average out at 150$/b or higher. I doubt air travel would disappear, but I don't see how cutbacks could be avoided. The Tor-Mtl especially. As I understand it, short-medium haul flights tend to be the least fuel efficient and most sensitive to fuel jumps (compared to an A380 hauling 850 cattle class passengers over the Pacific). So, I think if oil prices follow their long term trend lines would improve the business case of HSR relative to Air and road. (that is, unless Canada opts for that idiotic Bombardier JetTrain proposal. What an idiotic idea that is...)
Air Canada's CEO pointed out years ago that the company simulatde $100/b when planning out its fleet purchases which is what led to the large B787 Dreamliner buy. He was mocked at the time. He's since been proven to be more than prudent. Likewise, Westjet uses relatively efficient aircraft as well and keeps their costs low through other practices (common fleet, simple fare/service structure, etc). And Porter is showing no signs of struggling with it fuel sipping aircraft. Canadian airlines (like our banks) are thankfully, nowhere close to their American counterparts in fiscal performance. They've seen losses as a result of a slumping economy leading to reduced corporate and tourist demand, but their losses have been relatively minor compared to the bloodbath elsewhere in the global aviation industry and compared to their own revenues.
You are right though, that sustained high oil prices would probably lead to some reduction in air travel. But again, I would point to the likely system response....higher oil prices might finally force the public (and airlines) to fly on turbo-props for short-haul instead of larger jet aircraft. If airlines replaced their RJ and low end short haul fleet with the large turboprops that are being proposed, they could continue making profits on short haul at $150/b. Aside from high oil prices, carbon policies in Europe might achieve this shift on their own. Several aircraft manufacturers, with Bombardier in the lead are proposing 90+ seater turboprops that would make most RJs obsolete.
Secondly, if we were serious about HSR, we should sell off the 401. It makes absolutely no sense to subsidize competing modes. In 2006, Indiana leased it's toll road for 75 years for an upfront fee of roughly 15m per km. Prorating that to 401 would land Ontario with roughly 12b (though, the 401 should be much more valuable being the busiest highway on earth and all). That alone should be able to incentavize a private consortium to build a HSR. The resulting tolls I imagine the 401s owners would implement would shift some demand towards rail.
Probably the only way to make HSR really feasible in Canada. At present all HSR will accomplish is divert air travel to rail. There's hardly any incentive for governments to spend tens of billions of dollars to tackle the 1% of emissions caused by air travel when the 30%+ block of emissions from passengers car and commercial trucking can be given a serious dent with the same amount of money.