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Originally Posted by Richard Eade
A tunnel for buses would have needed to be wider, since OC Transpo would have insisted on passing at stations.
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Not just at that, but since buses require longer dwell times and are less platform efficient, the platforms would need to be longer. Also, the tunnel itself would need to be wider to accommodate driver error (trains follow the tracks, so don't need as much clearance).
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However, bus platforms could have been staggered; the west-bound and east-bound platforms don’t need to be across from each other. Remember, buses can make relatively small-radius turns to adjust their path quickly. The east-bound station could consist of a single west-bound bus lane, two east-bound bus lanes (one for stopping in and one for passing), and the platform. The west-bound platform, further along the tunnel would have a similar, but opposite, configuration. Thus, the total width would be three bus lanes and a platform – instead of two train ‘lanes’ and two platforms. Yes, the tunnel would have been wide for a longer length, but it still would have had no problem fitting within the city’s Rights of Way under Queen and Rideau.
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But with staggered platforms, would have required a larger concourse area, meaning more rock to be excavated, thus increasing cost.
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Ramps can be much steeper for buses, which might have allowed for a shorted tunnel length.
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True about buses handling steeper grades, but I don't see how, given current tunnel configuration, it would have resulted in a shorter tunnel. The western portal is at Nanny Goat Hill, so I don't think they would have saved any tunnel length there (I can't imagine the portal being any further east). The eastern portal is just over 100m south of Laurier. I don't think they would want it much further north as there is an advantage to keeping it grade separated with Laurier.
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The tunnel ventilation system would have had to be much more expensive. Perhaps so, but the requirements for the ventilation system are already a lot higher than most people realize. Even with an electric train, the ventilation system must be able to handle any possible smoke and chemicals within the tunnel. Thus, there are already huge ventilation shafts and fans which are designed to keep fumes away from the stations. It might simply be a case of running them at a slow speed all the time. There is also the option of running buses with 100% electric propulsion through the short tunnel.
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Were hybrid buses available 30 years ago? There were trolley buses but I don't know of anyone using a hybrid bus then. Because you can't use the wheels for a return feed, trolley buses require two pickups and aligning them is typically a manual process, so the transition would have required the driver getting out and manually connecting it, which would slow everything down.
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A bus tunnel would simply move the bus lines from the surface to underground. I don’t believe that there was ever a plan to completely strip the surface of buses. Cities need buses on the surface; even when those cities have a well-developed underground transit network. Of the approximately 200 buses per hour (during the peak periods) running through the core, probably only about 70% would have been moved underground. At 140 buses per hour, I believe that the underground station would have run relatively smoothly.
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I don't think anyone is suggesting that all buses be removed from the surface. Even with the Confederation Line, we will still have local buses downtown. I don't think anyone would want the rapid and express buses bypassing an over capacity tunnel though. There would be pressure to expand or twin the tunnel or convert to rail.
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A bus tunnel would have cost a lot more. I expect that this is true, but, remember, the cost of the LRT system is $2.1B for Stage 1 + $4.6B for Stage 2 + $??B for Stage 3. This is because the entire line needs to be completely converted before it is useful. The LRT tunnel itself came in about $650M and the rest of the BILLIONS of dollars are REQUIRED to convert the Transitway to rail. If a bus tunnel had been built, then the remaining Transitway could have been used. There is no need to convert the rest of the Transitway to a Transitway. So, even if the bus tunnel cost, say, $1B, that would be the total of what was REQUIRED for the line to be functional. Of course, there could still have been a lot of upgrades to the existing Transitway and the completion of missing links, but the total cost would likely only have been a portion of what it is costing to convert to a different technology.
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You are assuming that a bus tunnel built 30 years ago would meet today's capacity needs. I don't think this is a valid assumption. The most logical next move would have been to convert it to rail, and that would have required all the same extensions we are looking at today.
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People like to ride trains more than they like buses. Well, if a person is given the choice between taking a bus to transfer to a train to get to work verses taking a single bus directly to work, with most of the trip on a dedicated Transitway, they might opt for the bus. The speed of the trip might actually be faster on the single-seat bus ride. And, if the bus tunnel works as well as I believe it should, the buses will be reliable enough for people to schedule when they leave work to catch ‘their’ bus home.
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There is no way we could have crowds of people waiting for their 1 of 30 different bus routes in a downtown tunnel. We would have had a couple different routes using the tunnel and people transferring to their Connexion bus in the suburb, similar the way STO's Rapibus line works
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So, there is some thought added to the knee-jerk statements that people make about a bus tunnel. Yes, it would likely have cost more FOR THE TUNNEL, but the over-all system cost would likely have been much lower. Also, the buses could have maintained the single-seat ride that commuters have gotten used to.
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Don't forget the Transitway as it was built went way over budget and ended up costing more than the initial estimates for LRT at the time. Now LRT could have also been over budget, but we can't assume the system would have been cheaper.
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Of course, those thoughts only take into account the CAPITAL cost of the system; the operating costs are undoubtedly higher with buses.
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And that is not trivial either.
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