[BurlOak]

The savings would come from not having to equip the line with ventilation and expensive emergency exit tunnels (the EE's would just be a set of metal stairs every x metres). Stations would need to be partially underground, but because of track depth, they wouldn't be double-levelled stations. Think Dundas Station, only right beyond the end of the platform it would become open air.

It seems TTC does everything possible to build deep tunnels and stations. I understand the reason is they want to go under utilities (sewer, water, natural gas, telephone). Is this really the case or is it to minimize surface disruption? I do not think it really accomplishes the latter since the deeper stations lead to more massive excavations, although not continuous along the route, there are much longer construction times. Would these utilities generally be located under the centre of the road, or more typically under the sidewalks and edge of road?

I am not sure how a section would be decked over or covered. It would have to be fully below grade in order to pass the cross streets. With an open decking, salt and slush would enter affecting the life and possibly performance of the trains. I imagine there may be open deck size requirements to ensure people do not fall through (or things do not get dropped onto the tracks) – if the openings are too small, they may become clogged with snow and loose their ventilation abilities. I think it would be better to have a solid decking – essentially, a tunnel immediately below the road. I imagine ventilation needs increase with the depth of the tunnel, so it would still be significantly less onerous than for the deep tunneling. Although I could be wrong, I see the ventilation opening being on the side of road or sidewalk, with a vertical shaft and horizontal section leading to the tunnel itself. This keeps the slush of the tracks.

 

[denfromoakvillemilton]

I'd much rather they just dig a trench in the middle of the roadway (the same spot where the at-grade LRT was going to be), and use the money saved compared to tunnelling to push the line further west. The area is already an eyesore, and if the trench was landscaped properly (trees between the trench wall and the roadway, possibly a 1m buffer on each side of the trench), I think it would look not half bad. And if you want sections with a nice stylized wide median, you can deck the trench over.

That would be so nice. Have each station be decorated as well.

Gweed you really need to be involved with the process at city hall. You have to many ideas to be wasted on some message board.

 

[gweed123]

That would be so nice. Have each station be decorated as well.

Gweed you really need to be involved with the process at city hall. You have to many ideas to be wasted on some message board.

Haha, thank you. But to be fair a lot of the ideas I post on here are rehashed and/or tweaked ideas that other forum members have posted.

 

[gweed123]

It seems TTC does everything possible to build deep tunnels and stations. I understand the reason is they want to go under utilities (sewer, water, natural gas, telephone). Is this really the case or is it to minimize surface disruption? I do not think it really accomplishes the latter since the deeper stations lead to more massive excavations, although not continuous along the route, there are much longer construction times. Would these utilities generally be located under the centre of the road, or more typically under the sidewalks and edge of road?

I think it would vary depending on the situation. Certainly some utilities would need to be relocated, but a lot of them would need to be relocated no matter what you do (storm sewers for example).

I am not sure how a section would be decked over or covered. It would have to be fully below grade in order to pass the cross streets. With an open decking, salt and slush would enter affecting the life and possibly performance of the trains. I imagine there may be open deck size requirements to ensure people do not fall through (or things do not get dropped onto the tracks) – if the openings are too small, they may become clogged with snow and loose their ventilation abilities. I think it would be better to have a solid decking – essentially, a tunnel immediately below the road. I imagine ventilation needs increase with the depth of the tunnel, so it would still be significantly less onerous than for the deep tunneling. Although I could be wrong, I see the ventilation opening being on the side of road or sidewalk, with a vertical shaft and horizontal section leading to the tunnel itself. This keeps the slush of the tracks.

When I say decked over I mean like a solid roof on top of the trench. The roof doesn't need to support much weight, just park land above it. For an example of this, look at the decking over of the Yonge line between Summerhill and St. Clair stations. Or if you prefer, look at the Tremont St. Subway in Boston when it passes underneath Boston Common. The roof of the tunnel is covered by a couple feet of topsoil, and then it's green space above.

What you described in the 2nd half of your post there is what I'm going for. Although Re: ventilation, I would imagine that it would have more to do with tunnel length than depth. The length of the covered section would need to be relatively short (I would guess about the length of a train, maybe a little longer), so that fans and stuff aren't needed to ventilate the area. If the tunnel is short enough, the wind can ventilate it.

 

[Nick.]

you seem to be missing the point, the drivers aren't going to like losing a lane to "park land" any more than dealing with streetcars

 

[gweed123]

you seem to be missing the point, the drivers aren't going to like losing a lane to "park land" any more than dealing with streetcars

Who ever said the drivers would be losing a lane? Sounds like you've been listening to Ford too much...

 

[Darwinkgo]

Trenches with straight walls are still very expensive compared to at grade. if you have lots of room you can use stable slopes for walls and it is cheap. Most of the trench you can see when you ride YUS is this type of very wide trench, even where it is now decked.

While you would have a savings due to ventilation and exists compared to tunnels with a narrow trench, it would still likely be more expesnive than elevated.

 

[gweed123]

Trenches with straight walls are still very expensive compared to at grade. if you have lots of room you can use stable slopes for walls and it is cheap. Most of the trench you can see when you ride YUS is this type of very wide trench, even where it is now decked.

While you would have a savings due to ventilation and exists compared to tunnels with a narrow trench, it would still likely be more expesnive than elevated.

This is very true, however for a lot of people in Toronto elevated is a non-starter, even on a stretch like the Golden Mile. Either trenched or elevated would work with me personally, I'm just suggesting the one that has the best chance of actually being adopted.

 

[11th]

Wouldn't a road with trenched railway in the middle, look like the Décarie in Montreal?

 

[gweed123]

Wouldn't a road with trenched railway in the middle, look like the Décarie in Montreal?

Sort of, except 1/5th the width, and with a hell of a lot less noise. And it's not a trench through a vibrant neighbourhood like the depressed portion of the Spadina expressway was to be, it's an LRT trench that would be surrounded by power centres.

 

[11th]

Well, unless the city does not want to densify Eglinton East, I'd prefer elevated on the power centres stretch, and trenched for any future Eglinton West extension (in the ROW next to the road). Imagine direct access to an elevated station from the 3rd floor of a building's podium.

 

[Fred.S]

All this talk of trenching and elevating... I think at-grade could work very well if done right and be just as good as grade-separating the line. They just need to program all the lights on the route properly and sync them with a GPS tracking system, and minimize the number of stations to 800-1000m spacing.

There's youtube videos of buses and trams in Europe that very rarely get a red light. The traffic lights change to green just before the vehicle reaches them. If there's room on the streets and all lrvs and intersection lights are properly controlled centrally then the system could work just as well as a subway.

The only big disadvantage would be the possibility of car accidents blocking trains, but a big plow on front of the LRVs would take care of that issue

 

[gweed123]

Well, unless the city does not want to densify Eglinton East, I'd prefer elevated on the power centres stretch, and trenched for any future Eglinton West extension (in the ROW next to the road). Imagine direct access to an elevated station from the 3rd floor of a building's podium.

I'd be up for that for sure. Elevated or trenched, as long as it's separated from traffic and not in a tunnel.

But somehow I don't think Eglinton East is going to be the subject of much densification. Maybe a few condos around the stations, but that's about it. It isn't going to become a grand boulevard anytime soon. I would venture to say that most of the densification is going to be occurring between the Don River and Jane St.

All this talk of trenching and elevating... I think at-grade could work very well if done right and be just as good as grade-separating the line. They just need to program all the lights on the route properly and sync them with a GPS tracking system, and minimize the number of stations to 800-1000m spacing.

There's youtube videos of buses and trams in Europe that very rarely get a red light. The traffic lights change to green just before the vehicle reaches them. If there's room on the streets and all lrvs and intersection lights are properly controlled centrally then the system could work just as well as a subway.

The only big disadvantage would be the possibility of car accidents blocking trains, but a big plow on front of the LRVs would take care of that issue

As pointed out earlier, if a line runs at-grade, it limits the length of the train to 2 cars, which could have severe effects on the capacity of the line. This was ok when the Eglinton line was running independent of the SLRT, but now that they're interlined capacity could become an issue.

 

[Platform 27]

All this talk of trenching and elevating... I think at-grade could work very well if done right and be just as good as grade-separating the line. They just need to program all the lights on the route properly and sync them with a GPS tracking system, and minimize the number of stations to 800-1000m spacing.

There's youtube videos of buses and trams in Europe that very rarely get a red light. The traffic lights change to green just before the vehicle reaches them. If there's room on the streets and all lrvs and intersection lights are properly controlled centrally then the system could work just as well as a subway.

The only big disadvantage would be the possibility of car accidents blocking trains, but a big plow on front of the LRVs would take care of that issue

The problem is what it does to north-south vehicle movement on busy streets like Victoria Park or Warden. If you have a trains spaced at three minute headways, both directions, and each pass by a 100m-long train forces the intersection to close to car movement for 20 seconds, then you're talking about something like 70 seconds open, 20 seconds closed, 70 seconds open and so on. You don't have to believe in a war on the car to realize this will have some nasty effects.

Calgary does high-speed at-grade really well, but even they grade-separate once the crossing roads get to a certain size. The busiest arterial I reckon that crosses Calgary's LRT at-grade where it's median-running is probably 32 Ave NE, which is quieter than a Victoria Park or Warden. Calgary has grade separated most of the other crossings that're equivalently busy.

 

[Darwinkgo]

The other road which the LRT in Calgary crosses at grade which is quite large is Heritage Drive. There is a project to grade seperate it in the next decade. http://g.co/maps/benre