Danforth Line 2 Scarborough Subway Extension

[innsertnamehere]

I recall reading somewhere that the TTC had initially planned to run only 2 car trains on the subway in the off peak hours when it first opened, but that was quickly under capacity within a few months of opening and it got upgraded to 4 cars, later 6, then the full length trains we know today.

 

[nfitz]

Couldn't remember for sure, myself.........but did some googling...........here's your answer. (courtesy Transit Toronto)

Ah yes - I should have looked there. No indication if they ran the later cars in 4-car trains, other than Sheppard.

Interesting - the article notes that the original concept was for 10-car trains - with each car being only 48 feet (14.6 metres) - about the length of a small (CLRV or PCC) streetcar.

Presumably the 500 foot platform was a bit of safety, to make it easier not to miss the platform.

Which makes me wonder about Montreal.I think those cars are about 55.5 feet long making a 500 foot long 9-car train. They''ve been running ATM now for well over 40 years, so they hit the same spot every time (starting to wear down the platform materials from walking in spots!). But how well did that work in the 1960s and early 1970s before automation? Did they run 9-car trains back then? Though they do on the Yellow line, which as far as I know was never automated ... perhaps why it seems slow entering stations ... though I very seldom ever took it, even when living near downtown Montreal.

I wonder if that's why they were so keen to automate the Metro operation so early in Montreal!

 

[syn]

I recall reading somewhere that the TTC had initially planned to run only 2 car trains on the subway in the off peak hours when it first opened, but that was quickly under capacity within a few months of opening and it got upgraded to 4 cars, later 6, then the full length trains we know today.

That's correct - the demand for the subway was far greater than expected. They very quickly moved up to 6 car configurations, and then 8.

It's no surprise the DRL has been proposed for decades - transit experts and planners knew the Yonge Line was going to hit capacity sooner rather than later. It's also why we know the SSE will run under capacity and the Sheppard Line's issues are just s predicted.

 

[Northern Light]

Ah yes - I should have looked there. No indication if they ran the later cars in 4-car trains, other than Sheppard.

Interesting - the article notes that the original concept was for 10-car trains - with each car being only 48 feet (14.6 metres) - about the length of a small (CLRV or PCC) streetcar.

I definitely remember the H-series cars being shortened to 4s outside of the peak. I remember being on a train as a little kid that was shortened at Warden Station (then the end of the line), they decoupled a pair, and maintenance staff got on board the decoupled pair and began mopping it, as it decamped for Greenwood Yard, while the rest of the cars would go onward after giving the de-coupled pair a head start.

Aside from that, the TTC used to have markers under the platforms (probably still do) indicating when to cut the motor, and when to begin breaking and where to stop.

The markers came in 2-colour sets, black and white, and black and yellow, one for the G-Series (red trains) and one for all the others.

Each marker set had a number on it, 4, 6 or 8 which was for the length of the train.

As different lengths of train had different stopping speeds.

 

[lenaitch]

I definitely remember the H-series cars being shortened to 4s outside of the peak. I remember being on a train as a little kid that was shortened at Warden Station (then the end of the line), they decoupled a pair, and maintenance staff got on board the decoupled pair and began mopping it, as it decamped for Greenwood Yard, while the rest of the cars would go onward after giving the de-coupled pair a head start.

Aside from that, the TTC used to have markers under the platforms (probably still do) indicating when to cut the motor, and when to begin breaking and where to stop.

The markers came in 2-colour sets, black and white, and black and yellow, one for the G-Series (red trains) and one for all the others.

Each marker set had a number on it, 4, 6 or 8 which was for the length of the train.

As different lengths of train had different stopping speeds.

Interesting - I did not recall that, but I misspent most my youth on the Yonge line, but do recall the signs under the platforms. I wonder if that's why there is the stub siding at Warden.

 

[BurlOak]

Fourth stop proposed for already-costly Scarborough subway extension

If they want a station, it would have to be a cut-and-cover line, so that there would be savings to offset the costs of the added station.
The question I have is, what to do with the 2 West Highland Creek crossings (Trudelle Park and Pringdale Ravine) south of Lawrence. The southerly crossing looks quite shallow, and likely the line would have to go under. The more northerly (Pringdale) crossing seems to be a somewhat deeper valley and it may be possible to build a bridge with subway below - but I suspect that even here you may have to go under.

 

[Northern Light]

If they want a station, it would have to be a cut-and-cover line, so that there would be savings to offset the costs of the added station.
The question I have is, what to do with the 2 West Highland Creek crossings (Trudelle Park and Pringdale Ravine) south of Lawrence. The southerly crossing looks quite shallow, and likely the line would have to go under. The more northerly (Pringdale) crossing seems to be a somewhat deeper valley and it may be possible to build a bridge with subway below - but I suspect that even here you may have to go under.

100% you are going under.

I used to drive along Danforth there to get to work.

The dip is quite small, there is no way the tracks would exceed the floodplain w/o being at grade w/homes on either side.

****

The real challenge for the line is the ravine crossing just north of Lawrence.

To cut under that, which is the assumption; based on where the water table sits, you have to be very deep, making the station, rather expensive.

Cutting above was ruled out, I'm not sure that its impossible, but it probably triggers lots of expropriation on the north side of the ravine as the train dives down again.

 

[BurlOak]

The real challenge for the line is the ravine crossing just north of Lawrence.

To cut under that, which is the assumption; based on where the water table sits, you have to be very deep, making the station, rather expensive.

Cutting above was ruled out, I'm not sure that its impossible, but it probably triggers lots of expropriate on the north side of the ravine as the train dives down again.

Was going above discussed in any official way?

I was thinking of raising the profile of McCowan by about 3.0 to 3.5 metres. Add to this the current bridge beams that are likely about 1.0m deep and you would keep the bridge soffit elevation roughly the same. With bridge girders of 4.5m deep, it could easily span twice the current bridge - so passing the Regional Storm should not be a problem.

 

[Northern Light]

Was going above discussed in any official way?

No

I was thinking of raising the profile of McCowan by about 3.0 to 3.5 metres. Add to this the current bridge beams that are likely about 1.0m deep and you would keep the bridge soffit elevation roughly the same. With bridge girders of 4.5m deep, it could easily span twice the current bridge - so passing the Regional Storm should not be a problem.

Uh uh.

The current bridge sits very low over the creek.

You might be fine for regional storms; though w/increasing intensity, I don't think I'd want to bet on it.

The area below that bridge floods with some regularity. The ground is routinely saturated. Creekside erosion is a material issue.

The safe plan here would be, at minimum for the 100 year storm.

(which may soon be the 25-year storm, or less)

It wouldn't be impossible to situate the right height, but it would be expensive and challenging, unless you went over-grade. above Lawrence; but that comes with a different set of challenges, and likely no less expense.

 

[BurlOak]

No



Uh uh.

The current bridge sits very low over the creek.

You might be fine for regional storms; though w/increasing intensity, I don't think I'd want to bet on it.

The area below that bridge floods with some regularity. The ground is routinely saturated. Creekside erosion is a material issue.

The safe plan here would be, at minimum for the 100 year storm.

(which may soon be the 25-year storm, or less)

It wouldn't be impossible to situate the right height, but it would be expensive and challenging, unless you went over-grade. above Lawrence; but that comes with a different set of challenges, and likely no less expense.

I'd guess that bridge was built post-Hurricane Hazel. It's already designed for the 1000 year storm - or whatever Hazel was.

 

[nfitz]

I'd guess that bridge was built post-Hurricane Hazel. It's already designed for the 1000 year storm - or whatever Hazel was.

It would be designed for Hazel - which locally is the regional storm. It's been a while since I looked at that stuff, but it's probably more like a 200-year storm ... but the big change in assumption is that it starts slowly, so that everything is completely saturated before the main event hits - so it's entirely run-off ... rather than the typical

I suspect the worst-case scenario, is that things are at/near flood stage before the regional storm starts ... I suspect that hasn't really been accounted for if using a 100-year rain event to model a 100-year flood - where you have very intense rain. Though I've not delved into the details of how they formulate this for decades - perhaps things have advanced.

 

[Northern Light]

I'd guess that bridge was built post-Hurricane Hazel. It's already designed for the 1000 year storm - or whatever Hazel was.

This image from a City of Toronto presentation is of the Birkdale Ravine, after the August 2005 storm.

Its just upstream from the McCowan bridge over the Bendale Branch of Highland Creek.

ICLR Friday Forum: Reducing flood risk in Toronto (February 2016)

ICLR held a Friday Forum workshop February 19, 2016 entitled 'Reducing flood risk in Toronto', led by David Kellershohn with Toronto Water. Urban flooding cont…

www.slideshare.net

There is insufficient 'wiggle room' for a subway near the height of the existing bridge.

From a higher elevation, it may be do-able, but it would be destructive to greenspace, and costly.

I would only be surmising, but based on the low crossing of the East Don over Leslie, I think the TTC would look to build a fully sealed tunnel-bridge, rather than an open one.

I also imagine they considered it and ruled it out. Keep in mind the depth the tunnel would have to come from in the south, having gone under Highland Creek (different branches) twice before.

 

[BurlOak]

This image from a City of Toronto presentation is of the Birkdale Ravine, after the August 2005 storm.

Its just upstream from the McCowan bridge over the Bendale Branch of Highland Creek.

View attachment 189357

ICLR Friday Forum: Reducing flood risk in Toronto (February 2016)

ICLR held a Friday Forum workshop February 19, 2016 entitled 'Reducing flood risk in Toronto', led by David Kellershohn with Toronto Water. Urban flooding cont…

www.slideshare.net

I'd suspect doubling the span of the bridge would help.

There is insufficient 'wiggle room' for a subway near the height of the existing bridge.

From a higher elevation, it may be do-able, but it would be destructive to greenspace, and costly.

I would only be surmising, but based on the low crossing of the East Don over Leslie, I think the TTC would look to build a fully sealed tunnel-bridge, rather than an open one.

I also imagine they considered it and ruled it out. Keep in mind the depth the tunnel would have to come from in the south, having gone under Highland Creek (different branches) twice before.

Maybe it's a similar argument to the Ontario Line crossing of the Lower Don.

If you are using TBM south of Highland, and also North to get into STC - then you would not even think about the idea of having the subway cross above this main branch of the river under the road. If you are using cut-and-cover both north and south, then it's a totally different story.

 

[nfitz]

If you are using TBM south of Highland, and also North to get into STC - then you would not even think about the idea of having the subway cross above this main branch of the river under the road. If you are using cut-and-cover both north and south, then it's a totally different story.

Why deviate from the current TBM design, that has the emergency exit near where the north end of the platform would be? (we are talking about Lawrence, right?)

 

[CityStay]

I'm looking forward to the announcement of a fifth station. Or maybe paring back to two stations. Or back to one. Or three with an option on a fourth...

At any rate, more of an issue for my grandchildren as they will have to carry on the discussion long after I'm gone.