Subway Interlining ...

[golodhendil]

^ how is it like in Chicago?

In Boston, both the Red and Green lines have multiple end branches (2 for Red, 4 for Green) that share the same central section, so it's basically the same as interlining. Other than the fact that the wait could get a little frustrating on the Green line during off hours (when you see trains on the other branches passing by and not yours), I don't see significant shortcomings with the setup.

As for NYC, the few times I was there I have not experienced any major problems either.

Interlining and/or multiple end-branches is actually very common around the world, such as the London Underground. and the Japanese systems like Tokyo's where the metro, suburban, outer-suburban and mainline often share the same corridor or even same tracks/platforms. Not that I support reintroducing interlining to Toronto though. With the current network, I do not see a need for this.

 

[Chuck]

I'd suggest anyone proposing interlining take a trip around the Chicago Loop or the New York subway where these things actually happen.

One of the key components of New York interlining is the use of 4-track cross sections. Given the high frequency of trains on both the Bloor and YUS subways, it would be difficult to seamlessly merge the two lines. If someone simply holds the doors open on a train, this alone could mess up rush hour on both lines. Or, if a train breaks down on University, this would inadvertently shut down half the capacity on the Bloor line.

If the Bloor trains merged onto University using two new tracks, interlining could occur rather easily as the two lines would still operate independently of each other. The Bloor interline trains might even get their own set of tracks on the Bloor line - the existing BD trains would operate as is, but the interline trains could offer express service maybe as far west as Dundas West. This is exactly how New York interline trains work.

It's all hypothetical of course, and I still think that the DRL is a better use of funds.

 

[LowerBay]

^ how is it like in Chicago?
Not that I support reintroducing interlining to Toronto though. With the current network, I do not see a need for this.

Let me get this straight ... Bloor-Yonge is a hell-hole at 8:45am, and you don't see a need for interlining the Bloor and University routes, as the original designer intended?

 

[LowerBay]

One of the key components of New York interlining is the use of 4-track cross sections. Given the high frequency of trains on both the Bloor and YUS subways, it would be difficult to seamlessly merge the two lines. If someone simply holds the doors open on a train, this alone could mess up rush hour on both lines. Or, if a train breaks down on University, this would inadvertently shut down half the capacity on the Bloor line.

If the Bloor trains merged onto University using two new tracks, interlining could occur rather easily as the two lines would still operate independently of each other. The Bloor interline trains might even get their own set of tracks on the Bloor line - the existing BD trains would operate as is, but the interline trains could offer express service maybe as far west as Dundas West. This is exactly how New York interline trains work.

It's all hypothetical of course, and I still think that the DRL is a better use of funds.

There will always be waits inside the wye. If the TTC expects a train to never see a red in the wye, that's pretty unrealistic. If the Bloor trains had their own tracks on University, it wouldn't be interlining.

 

[golodhendil]

One of the key components of New York interlining is the use of 4-track cross sections. Given the high frequency of trains on both the Bloor and YUS subways, it would be difficult to seamlessly merge the two lines. If someone simply holds the doors open on a train, this alone could mess up rush hour on both lines. Or, if a train breaks down on University, this would inadvertently shut down half the capacity on the Bloor line.

If the Bloor trains merged onto University using two new tracks, interlining could occur rather easily as the two lines would still operate independently of each other. The Bloor interline trains might even get their own set of tracks on the Bloor line - the existing BD trains would operate as is, but the interline trains could offer express service maybe as far west as Dundas West. This is exactly how New York interline trains work.

It's all hypothetical of course, and I still think that the DRL is a better use of funds.

Agreed. Case in point: Just today on Boston's Green line during the morning rush hour, there was a signalling problem on one of the outer branches, and trains on all four branches going outbound (eastward from downtown Boston) was backed up all the way to the other terminus. As I rode inbound towards downtown, I started seeing 3-4 trains all lined up from one station to the next. When I saw 10-15 trains backed up by the time I reached where I was getting off, I knew something was direly wrong. Without an extra track / set of tracks, interlining/multi-branching is very precarious.

Let me get this straight ... Bloor-Yonge is a hell-hole at 8:45am, and you don't see a need for interlining the Bloor and University routes, as the original designer intended?

I know full well how much of a hell-hole B-Y is during rush hours, but considering all the present and near-future features of Toronto's network (including how far off the automation of BD is), I think it is more cost-effective to advocate for building the DRL to expand the network before spending money on the necessary peripherals for interlining. I also think building a higher-grade transit corridor along Eglinton will relieve B-Y to a good extent, because people can go all the way to Eglinton before going E/W. That's why I feel the more important it is to spend good money on Eglinton and do it right, as a subway or subway-substitute that can speed people away from Yonge and Spadina, rather than a half-assed local service that is no more than a glorified bus. But that's discussion for another thread.

 

[nfitz]

The interlining I'd like to see is a circle line of sorts running from Union, up University through Lower Bay, and back down Yonge to Union. I don't know whether something like this is even remotely feasible, or even necessary, but it would probably be worth thinking about.

If London has finally concluded that operationally a Circle line doesn't work, because there's no easy way to fix service gaps, and is finally abandoning a circular service; why would we want to start one?

 

[Chuck]

Let me get this straight ... Bloor-Yonge is a hell-hole at 8:45am, and you don't see a need for interlining the Bloor and University routes, as the original designer intended?

LowerBay, think of it this way: There are currently four inbound subway tracks that approach downtown today - southbound Yonge, southbound University, eastbound Bloor, westbound Danforth. Crowding exists because these four tracks merge into two - southbound Yonge and southbound University, both of which are already operating at 100% capacity. Interlining or not, there will ultimately be the same four subway lines merging into two, and therefore the same overcrowding. As a result, interlining would simply shift the crowding from one location to another, or perhaps have no affect at all.

Crowding on the subway can only be mitigated when the number of tracks (not lines) entering the CBD increases from the current two. A DRL would raise this number to four, and would therefore dramatically decrease overcrowding.

An excellent idea would be to interline the BD subway with the new DRL because this option does in fact utilize new track capacity. An alternate idea would be to force 100% of outer BD trains onto the DRL, and have separate inner BD trains that only go from Dundas West to Pape.

Edit: Also to LowerBay, it is clear based on your name that you would like to see Lower Bay Station reopened. However, recall that back in the days of interlining, the University line did not exist north of Bloor, nor were the trains running every 2 minutes. The conditions that allowed interlining to work in 1966 are gone forever, therefore Lower Bay has no practical use in today's subway system. The only condition that would allow Lower Bay to be put back into use would be the introduction of 4-track express service on the BD. In that scenario, Upper Bay may serve express trains, while Lower Bay serves local trains, or vice versa.

 

[toraerach]

An excellent idea would be to interline the BD subway with the new DRL because this option does in fact utilize new track capacity. An alternate idea would be to force 100% of outer BD trains onto the DRL, and have separate inner BD trains that only go from Dundas West to Pape.

While your first idea makes some sense - interlining some trains on the DRL with outer B-D trains - I don't think a complete DRL-outer-Bloor-Danforth line could or should happen. First of all, you'd force a new transfer on an established transit corridor. People riding from Coxwell to Bloor-Yonge, for example, would have to switch trains at Pape, and people riding from Coxwell to High Park would have to either transfer twice or face a much longer ride. Secondly, this would limit any northern extension of the DRL. An extension to Eglinton and Don Mills, for example, would not be possible without reduced frequencies on the Danforth line East of Pape.

The thing that prevents interlining right now is not only the capacity issues (which are very important), but also the fact that the system wasn't built for it. Although the original B-D line was built with interlining in mind, subsequent extensions of the subway system did not. Interlining might have been possible in 1966, but that was before the Spadina line was built (which, I believe, can't be interlined with the Bloor line due to the lack of a rail connection between the two). When interlining was experimented with, the two lines served a combined 36 stations (if I count correctly). Today they serve a combined 60 stations, and after the two extensions of the Y-U-S line will serve a combined 72 stations. This includes two major transfer stations that did not exist before at Sheppard-Yonge and Kennedy. The two lines are, in effect, "too big to fail." One problem somewhere on the interlined system could potentially close down the entire two lines creating a huge mess. Not to mention the difficulty in managing such a huge system, nor the confusion it would present to users.

I'm not against interlining in all cases, but I don't think interlining the B-D and Y-U-S lines as they exist today as a good idea. Where I would like to see some interlining would be, as Chuck mentioned, some trains from the outer B-D line with some trains on the DRL. I would also like to see an extended Sheppard line share the Spadina extension North of Downsview with the Y-U-S line (though that idea has a lot of problems with it on it's own, differing train lengths being one). Maybe in a few decades/an ideal world the Eglinton and Bloor-Danforth subways could share an extension to STC.

 

[LowerBay]

However, recall that back in the days of interlining, the University line did not exist north of Bloor, nor were the trains running every 2 minutes.

In 1966, during rush hours ...

the Bloor-Danforth route ran with a headway of 4 min 30 sec.
the Bloor-University-Yonge route ran with a headway of 4 min 30 sec.
the Danforth-University-Yonge route ran with a headway of 4 min 30 sec.

FOR A COMBINED HEADWAY of 2 min 15 seconds on all parts of the system, except for train frequencies between Bay and St. George on the BD route platforms (which were obviously 4 min 30 sec).

The key difference is all that congestion is not moving though Bloor-Yonge and St. George stations as passengers walking up and down stairs and along platforms. That makes a huge difference in station dwell times. If those passengers are on the direct trains, the system can run more smoothly when all trains are scheduled and coordinated through the wye via automation.

It is also a myth that a breakdown shuts down the entire system. Actually, the opposite can happen. If there is a blockage, say, eastbound at Spadina before the wye, some eastbound service on Bloor further east of the blockage can be maintained by northbound University trains turning east on Bloor. Also, during major delays, the lines can separate until the problem clears. This was actually done in the 60s for delays exceeding 15 minutes.

 

[kEiThZ]

From Steve Munro:

http://stevemunro.ca/?p=116

 

[LowerBay]

I contributed to that article -- Steve has a few things wrong about the integrated system. First, the trains did not always run in their proper "batting order". Second, the illuminated signs on the upper platforms told us whether we should go downstairs to get the next eastbound (at Bay) or westbound (at St. George) train.

 

[Whoaccio]

Large scale interlining seems impractical. My experience with the MTA in NYC is that it is, considering the market it serves, bad. Headways are excessive in off peak hours and reliability is suspect.

It probably doesn't count as "interlining," but it may be worth making branch lines. I can't think of an appropriate route offhand, but it could be useful. If the Sheppard Line stays as is indefinitely, maybe we should make it a branch of the Yonge Line? 50% of trains would head towards Don Mills (or Vic Park, depending on how the Sheppard East LRT turns out) and 50% of trains to Finch or RHC.

 

[Chuck]

In 1966, during rush hours ...

the Bloor-Danforth route ran with a headway of 4 min 30 sec.
the Bloor-University-Yonge route ran with a headway of 4 min 30 sec.
the Danforth-University-Yonge route ran with a headway of 4 min 30 sec.

FOR A COMBINED HEADWAY of 2 min 15 seconds on all parts of the system, except for train frequencies between Bay and St. George on the BD route platforms (which were obviously 4 min 30 sec).

The key difference is all that congestion is not moving though Bloor-Yonge and St. George stations as passengers walking up and down stairs and along platforms. That makes a huge difference in station dwell times. If those passengers are on the direct trains, the system can run more smoothly when all trains are scheduled and coordinated through the wye via automation.

It is also a myth that a breakdown shuts down the entire system. Actually, the opposite can happen. If there is a blockage, say, eastbound at Spadina before the wye, some eastbound service on Bloor further east of the blockage can be maintained by northbound University trains turning east on Bloor. Also, during major delays, the lines can separate until the problem clears. This was actually done in the 60s for delays exceeding 15 minutes.

You're choosing to ignore the fact that Toronto built the Spadina line.

By 2020, Spadina will be at capacity due to added riders from the Eglinton whatever it will be, extension to Vaughan, and Transit City foolishly dumping 200 million new annual riders onto the existing subway system. Spadina trains currently run every 2.5 minutes, or 24 per hour. In 2020 when all trains run at 1.5 minute intervals, each track will handle 40 trains per hour. Since reduction of service on Spadina is not an option, that leaves 16 trains per hour for interlining, or 8 per hour per end of the Bloor line. This is a frequency of 7.5 minutes, or one out of every five inbound trains.

Do you really think that people going to a stop on the Yonge line are going to wait up to 7.5 minute for a train that only takes them to the University line, when they could instead catch a regular train running every 1.5 minute and just transfer at Bloor?

Recreating a 40 year old operating pattern is absolutely ridiculous. If you want to interline, interline with the DRL. The existing wye has no relevance today.

 

[LowerBay]

The only way you can interline with the DRL is to create wyes at Dundas W. and Pape that allow trains to run both in a circle, and from the outer ends to downtown and in reverse -- otherwise you cut the Bloor service west of Pape and east of Dundas W. in half.

I don't think ridership on Spadina will be as high as you predict though, but here's another idea -- what if the Spadina line is disconnected from University and extended down Spadina Av., replacing the streetcar, before turning at Queen and terminating downtown somewhere? That frees up the University line and Lower Bay to serve their original purpose. And, we get an extra pair of tracks into the core that increase overall capacity at a fraction of the cost of a full DRL.

As for Eglinton, thank Giambrone, Miller, and Munro. I'm going to give Steve Munro credit for turning our officials away from subway construction. His nagging of 35 years finally rubbed off.

 

[nfitz]

As for Eglinton, thank Giambrone, Miller, and Munro. I'm going to give Steve Munro credit for turning our officials away from subway construction. His nagging of 35 years finally rubbed off.

What an odd comment. Surely it is Steve Munro's recent presentation to the TTC that demonstrated that the Yonge subway line extension (which he seems to be generally in favour of, at least from an appropriate technology point-of-view) was going to create a massive problem at Yonge-Bloor, that could be completely mitigated by the construction of a DRL - that has turned the TTC towards the idea of downtown subway construction for the first time in over 40 years. Steve has never been anti-subway - just anti-subway when you don't need one. Given he's also been anti-BRT when it's not enough capacity, and anti-LRT when it's not enough capacity, then perhaps your trying to paint an unfair picture of him.

As to interlining ... I have to think that this is merely some kind of fantasy that is more to do with wanting to have Lower Bay station in use, than in reality.