Ottawa Rapid Transit Network developments

[Franky]

Originally Posted by Mille Sabords

The way I read the article, he was rambling on about how our project now seems to be on the "grander scale of Montreal or Toronto's subway" and that we're too small a burgh to dream that big, how dare we.

LRT is basically a long streetcar with a separate ROW. It would normally have at-grade crossing which brings it's price per km down. This also means that service cannot be every 90 seconds, there must be time for other traffic to pass. The BRT we have built on the other hand, have for the most part grade separated ROW as BRT requires. Converting BRT to rail takes you into subway territory and cost. The problem with Ottawa is we aren't even a million people yet and the capacity needed to justify a subway/metro expense just isn't there. I think that was David Jeanes' point - not that we don't "deserve" it.

If LRT is the only thing we can do as a transit improvement, we should put in LRT by creating new ROW and utilize at-grade crossings to keep costs low. The Carling line is a perfect example of real LRT.

One more interesting fact came out at the meeting. Their models project a 35% growth in inner city trips in the AM peak and 6% decrease in car travel! How can this be when Albert and Slater would open up and there would be more parking? Parking restrictions. Here's the kicker, if we don't limit parking downtown and collect revenue instead of subsidizing more transit users, growth to the inner area would "only" increase by about 23% and surface rail would probably work.

One more interesting point I think David Jeanes brought up WRT the 180m long tunnel platforms. He suggested we bore out the tunnels a little bigger so that double-deck trains could be used instead of 6 car trains. He made a good point about 180 m platforms requiring 180 m EVERYWHERE, because trains get filled up at the DT platforms and emptied along to the suburbs (some day). My thought was - why not go with Double-deck surface rail? Would that not almost double capacity of surface rail?

[Dado]

Originally Posted by Mille Sabords

The way I read the article, he was rambling on about how our project now seems to be on the "grander scale of Montreal or Toronto's subway" and that we're too small a burgh to dream that big, how dare we.

If he had been focused on details like tunnel depth or other technical matters on which he may have expertise, I think the comment would not have come off as a sneer to Ottawa's so-called "grand ambitions". It would've been constructive input.

I'm much more inclined to pay attention to an argument about tunnel depth and construction technique, than to someone starting off with telling me that my city doesn't deserve to think so big in the first place.

Just to be Devil's Advocate, how do you know he didn't? Do you think the two quoted sentences are the entirety of what he said to the Sun's reporter? But all that other kind of stuff that you allude to would be pretty boring fare for the media, especially the Sun - much better to get something juicier about it costing too much and being too grand, even if it is out of context. Think about the who the Sun's audience is as well and whether they're going to be interested in the finer points of tunnel depth and building underground stations. Last night for example his question to the consultants was about ensuring that the tunnel diameters are large enough for bi-level trains but you don't hear about that in the media because it's too specific and has no real dramatic value - yet that kind of question is clearly about capacity in the distant future, one that he'll likely not even be around to see.


I also happen to know that when the MTF came out with its tunnel proposal that he actually had developed some plans on how to integrate stairs and escalators at Union Station into a new underground transit station. I saw the plans at one of the TMP round-table sessions. He's already figured out how to give passengers arriving at Union a 'grand' entrance based on his knowledge of the station, but again, no great media excitement value in it because it's not even something they'd think to ask about.

[electricron]

Originally Posted by d_jeffrey

This is what Frankie was complaining about. Why are they going with a tunnel so deep anyways? To pay twice the costs, with less stations, to prevent disruption on 2km? May I remind them that the original LRT plan was even more disruptive? It's the best example of being enamored with a process.

The costs of the Notre-Dame highway in MTL doubled, because the engineers decided the new model would be nicer, and damn the price! The minister was furious, and blasted them through the media.

Engineers and designers are never satisfied. They have an inner voice telling them to keep making it better.

[Dado]

Originally Posted by d_jeffrey

This is what Frankie was complaining about. Why are they going with a tunnel so deep anyways? To pay twice the costs, with less stations, to prevent disruption on 2km?

It was to put the depth below that of the foundations of many of the buildings to allow the tunnel to take an off-grid path.

[p_xavier]

Originally Posted by electricron

It Engineers and designers are never satisfied. They have an inner voice telling them to keep making it better.

Well someone needs a real voice to tell them to be more efficient.

[p_xavier]

Originally Posted by Dado

It was to put the depth below that of the foundations of many of the buildings to allow the tunnel to take an off-grid path.

Of course it was, which is why many here wanted a Queen-Daly alignment to reduce the costs considerably, but I don't see that in the "scope" of the consultants, they are in the business to make money.

[lrt's friend]

Originally Posted by d_jeffrey

This is what Frankie was complaining about. Why are they going with a tunnel so deep anyways? To pay twice the costs, with less stations, to prevent disruption on 2km? May I remind them that the original LRT plan was even more disruptive? It's the best example of being enamored with a process.

The costs of the Notre-Dame highway in MTL doubled, because the engineers decided the new model would be nicer, and damn the price! The minister was furious, and blasted them through the media.

Doesn't this all go back to the Albert/Slater coalition? I have said it before that they are dictating the design through downtown to minimize disruption of their businesses. That may be good for them, but if it is spiralling costs much higher, this is impacting all taxpayers, and if costs are becoming excessive for downtown, then this is affecting our ability to fund the whole rapid transit system.

[Franky]

Originally Posted by Dado

It was to put the depth below that of the foundations of many of the buildings to allow the tunnel to take an off-grid path.

Only one option is termed "cross country" and is that worth the long escalator ride and extra cost? It should be seriously studied. And speaking of studies, what is with that unweighted scheme to select the "right" option?

[Skyway]

Ottawa residents get detailed look at transit tunnel plans
Last Updated: Friday, February 27, 2009 | 10:32 AM ET Comments8Recommend6CBC News
Dozens of Ottawa residents got their first opportunity to see what the city's future downtown transit tunnel might look like during an open house at city hall Thursday night, while planners took note of the public's reaction.

The tunnel from Lebreton Flats to the University of Ottawa will cost $600 million to build, according to city staff. It will be part of a $1.7 billion first phase of the city's proposed transit plan, which includes light rail from Tunney's Pasture to Blair station.

Potential tunnel and surface routes, possible station locations and proposed designs were all posted on colourful boards, in far more detail than at a similar open house held last December.

While perusing the boards, many residents appeared to already have strong opinions about the tunnel.

"I'm a downtown resident, and I'm worried about all the construction and the costs that are gonna happen with the tunnel," said Thomas Geiger.

"It's, like, well overdue," said Miklos Horvath. "I've been here almost 20 years and we're still riding old technology — buses."

"What worries me is that they seem to be [boring the tunnel] very low. But maybe they have to, to get under all the buildings," said Margaret Black.

"What kills me is I think nothing's gonna happen for decades," said Ida Henderson.

The project manager, David Hopper of Delcan Corp., listened carefully to the comments and answered questions. Delcan is in charge of transit-tunnel planning and the environmental assessment for the project.

"We're going to go through all the comments and start compiling them," he said. "We have a four-page questionnaire for people to complete about everything we're doing. So we'll go back, finalize our evaluation, and prepare our technical evaluation from there."

Delcan's recommendations will be presented to a city committee in May.

Construction is expected to start in the spring of 2012

[lrt's friend]

I thank Dado for his comments. He is making some very good points.

[lrt's friend]

One more interesting point I think David Jeanes brought up WRT the 180m long tunnel platforms. He suggested we bore out the tunnels a little bigger so that double-deck trains could be used instead of 6 car trains. He made a good point about 180 m platforms requiring 180 m EVERYWHERE, because trains get filled up at the DT platforms and emptied along to the suburbs (some day). My thought was - why not go with Double-deck surface rail? Would that not almost double capacity of surface rail?

I presume we already know that our Transitway alignment and the various overpasses can handle double decker trains

[Richard Eade]

Creating an underground rail system will be messy. There will be a significant amount of digging from the surface, despite the tunnel being bored. The Contractor has tried to choose routes which will minimize the inconvenience, but there will be disruptions.

For example, I have been a promoter of putting the west end of the tunnel under Slater instead of Albert. The contractor supports an Albert tunnel in the west. If we look at the disruption involved in each option, the Albert option can avoid some disruptions.



In the above graphic, the contractor's Albert line avoids the LeBreton development lands and is low enough to lanch the TBM before the bend of Albert. The blue line is a trench which doesn't need to be covered for most of its length.

The red line is the straight line to Slater. However, it involves a new structure for Albert. (Probably about $20M.) This would be disruptive because Albert would need to be temporarily detoured. Also, during the construction of this section, building on the development lands would be limited. Future buildings would need to straddle the tunnel, but that should not be too much of an issue for a new building design. Another issue might be that the green triangle between Albert and Slater is under NCC control. The red line would also be a trench, but might need to be covered in some areas.

So there have been a number of things which have been taken into account which are not necessarily as obvious as they could be. I think that there could be interim reports which detail a lot of the thought which has gone into the current offering.

[Dado]

Originally Posted by lrt's friend

Doesn't this all go back to the Albert/Slater coalition? I have said it before that they are dictating the design through downtown to minimize disruption of their businesses. That may be good for them, but if it is spiralling costs much higher, this is impacting all taxpayers, and if costs are becoming excessive for downtown, then this is affecting our ability to fund the whole rapid transit system.

I know they wanted a tunnel, but as to a deep tunnel, I'm not so sure. But deep stations would be less disruptive to surface traffic so maybe you're onto something.

That might be the answer to Franky's follow-up question to me about only the cross-country alignment going off-grid yet all the options seem to be going deep, even the on-grid options because if you're going to mine out a station, you need a reasonable depth of mineable material above you that's not going to collapse while you do it.

Interesting.

[Franky]

Originally Posted by Dado

I know they wanted a tunnel, but as to a deep tunnel, I'm not so sure. But deep stations would be less disruptive to surface traffic so maybe you're onto something.

I don't understand how/why deep cut&cover stations would be "less disruptive" than shallow cut&cover all along a road. If you block off Albert anywhere along it's length, that capacity is lost for the whole length. For example, buses would have to be rerouted whether there is one hole on Albert or the whole street is dug up.

[Richard Eade]

Originally Posted by lrt's friend

I presume we already know that our Transitway alignment and the various overpasses can handle double decker trains

The contractor is already concerned about the low height of the pedestrian bridge at St. Laurent for the regular trains. They want a clear 5m height.

[p_xavier]

Originally Posted by Franky

I don't understand how/why deep cut&cover stations would be "less disruptive" than shallow cut&cover all along a road. If you block off Albert anywhere along it's length, that capacity is lost for the whole length. For example, buses would have to be rerouted whether there is one hole on Albert or the whole street is dug up.

There is still hope for the procurement process. That's what happened for the Canada Line in Vancouver, they switched to cut and cover to lower the costs, and shorter stations but higher frequencies to offer the same service. But then again, doing procurement on numbers can be dangerous, because their stations are awfully short.

[Dado]

Originally Posted by Franky

I don't understand how/why deep cut&cover stations would be "less disruptive" than shallow cut&cover all along a road. If you block off Albert anywhere along it's length, that capacity is lost for the whole length. For example, buses would have to be rerouted whether there is one hole on Albert or the whole street is dug up.

I think you're confusing yourself now... they aren't going to be having deep cut&cover stations - just deep mined out stations.

You wrote that you asked about why not do shallow cut&cover and you got the 'line' about it being too disruptive, so that's why they're going deep. By going deep they can do most of the station without ever touching the surface - at a cost in both dollars and time. The only surface activities would be for the entrances, and many of those are going to be in neighbouring buildings, as-yet unbuilt buildings or in the sidewalk where disruption can be reduced to one lane or so.

The amusing part of this is that we were told that the reason for going deep is to get under the buildings, but I think we've now determined that that is only part of the story.

[Franky]

Originally Posted by lrt's friend

I presume we already know that our Transitway alignment and the various overpasses can handle double decker trains

Do you have a link to specification? I can't seem to locate any.

[Franky]

Originally Posted by Dado

I think you're confusing yourself now... they aren't going to be having deep cut&cover stations - just deep mined out stations.

You wrote that you asked about why not do shallow cut&cover and you got the 'line' about it being too disruptive, so that's why they're going deep. By going deep they can do most of the station without ever touching the surface - at a cost in both dollars and time. The only surface activities would be for the entrances, and many of those are going to be in neighbouring buildings, as-yet unbuilt buildings or in the sidewalk where disruption can be reduced to one lane or so.

The amusing part of this is that we were told that the reason for going deep is to get under the buildings, but I think we've now determined that that is only part of the story.

Actually, they said cut&cover was needed in the soft ground conditions of sandy hill area - no other way. The guy was not a decision maker, he said shafts for stairs and air shafts needed to be bored from the surface even for mined stations. I did not get the feeling a decision was made to mine the stations. I found a website for "BART Extension" which states
"
- Mined stations present greater risk to
construct (heaving of city streets & sidewalks)
- Significant cost penalty of $50 million more a
station
- Surface disruption of traffic not eliminated
(piping for freezing must be drilled & calcium
chloride brine solution continuously circulated
to maintain freeze)
- VTA recommends cut & cover method as
safest, “tried & proven technique” based on
experience constructing Vasona tunnel"
https://www.communicationsmgr.com%2Fproj...%2520Council%2520Workshop%255B1%255D.pdf
Granted, this is a specific case (I might look for more).

[Dado]

Originally Posted by Richard Eade

The contractor is already concerned about the low height of the pedestrian bridge at St. Laurent for the regular trains. They want a clear 5m height.

You mean the consultant?

And that doesn't hold any water for regular LRT vehicles. Double decker buses are higher than low-floor LRVs. Even Calgary's high-floor LRVs fit into tunnels with far less clearance than 5 m:


Source: LRT in Calgary

A clear 5 m height would also allow GO Train bilevels to clear a bridge since they're 4.85 m in height, bearing in mind that these are heavy rail vehicles:
http://en.wikipedia.org/wiki/Bombardier_BiLevel_Coach


The requirement for 5 m at St. Laurent is related to something other than standard LRVs...


Probably completely unrelated, but didn't we just acquire 3 double-decker buses? I wonder what would happen to a 4.25 m high double-decker bus passing under a bridge if it happened to hit a pothole or something? Sure would be nice to have some extra clearance for that. But like I said, probably completely unrelated.