Improving transit speed part 2 – Holladay

A continuation of the last improving transit speed post, which is building off of the discussion over at Portland Transport, and now specifically focusing on people’s suggestions for speeding up travel time along NE Holladay. I hope this provides something of an operational perspective as to why some things are the way they are and that might prove to be a hindrance in redesigning platform placement. These are not necessarily insurmountable obstacles, but are, at the very least, obstacles that prevent any of the suggestions from the Portland Transport post from being enacted immediately.

NE 7th Ave and OCC

Courtesy of Portland Transport, here are weekday passenger counts for eastbound stops on Holladay during fall 2010 (westbound not listed but they’re pretty comparable):

Stop—————–Ons—–Offs
Rose Quarter—–1,207—1,035
Convention Ctr.—–433—–595
NE 7th—————396—–764
Lloyd Center——1,000—1,830

Given those lower passenger counts compared to RQ and Lloyd Center, many people have put forth the argument that Convention Center and NE 7th could be closed to speed up travel time on Holladay without severe impact to passengers.

Not permanently…

However, both of those platforms serve an important purpose on Holladay – not so much for passenger loading, but rather as a necessity to travel along this section of the alignment. The short explanation is that those platforms are needed to call signals/switches on Holladay. The long explanation: keep reading.

For one thing, trains at all stops along Holladay need to call the pre-empt signals to proceed, which will then cascade into the next platform. But OCC & NE 7th have an additional complication. The alignment on Holladay from just past Rose Quarter to just before Lloyd Center is between two sets of switches. On the west (click for map), there’s a crossover as well as switches to diverge into the special events track, westbound main, or trolley barn at Rose Quarter. On the eastern side, there are switches to diverge a train into (or out of) the Doubletree Siding. Going back to my earlier posts on signal types, since all of these switches are in pre-empt territory, they are associated with ABS/pre-empt combination signals and are protected by ATS magnets.

Let’s start with the switches into the Doubletree Siding on the eastern side.

NE 7th Ave

Looking east from NE 7th

The above picture (click for larger) shows what an eastbound train at NE 7th sees. Of interest is combination signal 20A immediately prior to the Lloyd Center platform. The zoom lens makes it look closer than it really is – a better perspective (though not as clear of a photo) is this old picture from when NE 7th was where trains would switch radio channels to Main 1 or Main 3. In that linked photo, 20A is the red light at NE 11th.

In this above photo, you can see that the intersection at 9th is has a permissive white vertical pre-empt. Now look down to NE 11th at the combination signal 20A, which is displaying a yellow horizontal. This informs the operator of an eastbound train at 7th that the power switch that can diverge a train into the Doubletree Siding is aligned to continue east, but 11th is not pre-empted yet. 20A will time out back to a red after a minute, which reactivates the magnet until the next train calls it.

Approaching Lloyd Center, eastbound.
ATS magnet visible in foreground, white vertical on 20A in background.

When 20A is red, that ATS magnet will stop an eastbound train before it gets to the intersection at NE 11th. Therefore, 20A must be called by a train before it can proceed through 11th into the Lloyd Center platform, but it needs a place to call 20A from. Rolling calls, or in other words, pressing the call button as you move over a call loop without stopping, are a poor practice. Trains should be at a complete stop over a call loop to call a signal, so there needs to be some place for a train to stop prior to NE 11th to call 20A, and that purpose is served by the NE 7th platform. When placing the call at 7th, rail operators will look down to 20A from there and make sure it drops from a red before proceeding.

The NE 7th platform is needed for trains to go east to ensure that the switches for Doubletree are properly set, so 7th doesn’t work as a stop that can be closed or skipped since a train will have to stop there anyway to call 20A. (Plus 710 NE Holladay right by the platform at NE 7th is a TriMet building, so it’s unlikely that front-door MAX service is going to go away from there.)

Then over at Oregon Convention Center…

Oregon Convention Center (OCC)

West from Convention Center

Looking at OCC on the western side of the Holladay alignment, there are two combination signals that affect train movement from OCC to into Rose Quarter: 18A and 18B.

Signal 18A is located on the corner of NE Holladay & 2nd for westbound trains. It is associated with switches 13A, 11C, and 11D and the ATS magnet (visible in the above picture as the little yellow square) on the opposite corner of NE 2nd. If any of those switches are not properly set for a westbound move from OCC or if there is a conflicting move in progress – for example, a vintage trolley coming out of the trolley barn or turnbacks like last weekend’s streetcar work, 18A will remain red and a westbound train will be tripped at the ATS magnet. To proceed through here, 18A needs to be called by westbound trains from a platform (remember, no rolling calls), which is why OCC is needed.

West from OCC, 18B visible (displaying a red aspect, click for larger and look on the Rose Quarter platform)

Way down there by the Rose Quarter special events platform is signal 18B, an ABS/pre-empt combination signal that routes a train into the westbound main (click for a more up-close picture of 18B), the special events track, or the trolley barn. Like 18A, 18B is called by westbound trains from OCC, and both need to drop from reds before a train can continue west into Rose Quarter. 18B doesn’t have an ATS magnet of its own (the magnet at 2nd for signal 18A will stop a train before it gets near 18B) but this signal is still necessary for route selection. Both 18A and 18B will time out back to reds and will need to be called by the next westbound train, ensuring that the switches are properly set and there are no conflicting moves by other trains. As a result, OCC is another platform that can’t be skipped or closed because westbound trains need a platform to call 18A and 18B from. Similar to NE 7th, since trains have to stop here anyway to call the signals, they may as well service the platform.

White vertical on 18A, yellow horizontal on 18B

So can either of these stops be closed, moved, etc? Not easily.. NE 7th eastbound and OCC westbound are currently necessary to call their respective ABS/pre-empt combination signals to ensure switch alignment/no conflicting moves by other trains. And while their corresponding westbound and eastbound platforms don’t have combination signals, operators will still call for pre-empt signals to proceed from there. At present, I don’t really see a way to avoid stopping at both of these platforms despite the relatively low passenger on- and off-boarding at these locations. This isn’t to say that it can’t ever be done, but I don’t think skipping either of those platforms can be done as an immediate fix.

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23 responses to “Improving transit speed part 2 – Holladay

  1. I read this but it still hasn’t really sunk in for me — why exactly would changing the signaling situation to make rolling through these areas possible be so expensive/difficult that it’s not worth it? Is there some reason that’s not clicking for me that the problem just wouldn’t be fixable? I would have thought removing the platforms would have been the main contributor to the costs of such a project, not this stuff.

    • Well for one thing the pre-empts for trains only cascade between platforms, and at each platform operators call the signal to cascade them into the next platform. Eastbound that’s up from Rose Quarter to OCC, then from there to NE 7th, and then from there to Lloyd Center. Same deal for westbound trains – right now they only cascade between platforms, not down the length of Holladay. So (ignoring the switches and combination signals for a moment) there would still be necessary signal work to cascade those signals all the way up and down Holladay, and I really don’t know enough about traffic signalling through there to know the logistics of the work or money involved in doing that.

      But back to the switches and combination signals – it’s not just the signals in here that matter, it’s design of the alignment itself, including the switches. Even if you took out NE 7th, for example, the alignment between 9th and 11th still has switches to diverge into Doubletree, a combination signal to display how they’re set and if it’s safe to move, and an ATS magnet to stop a train if it’s not safe. You need a call loop prior to that area to select your route (either into the siding or continuing on the eastbound main). You have to be stopped over a call loop to place that selection. So since you have to be stopped to call the signal and make sure the switches are set right and there are no other trains in the way, it makes sense that you’re doing all of this while stopped at a platform since non-platform stops are not part of normal service.

      Same thing for OCC – you need to choose your route through the Rose Quarter platform (18B) and make sure that the switches are set right and that there are no conflicting moves by other trains (18A) because an ATS magnet is going to stop you if there’s another train or if the switches aren’t set. If there was no stop at OCC, where would you be able to choose your route from and ensure that it’s safe to move forward? You have to be able to stop somewhere prior to Rose Quarter to do that.

  2. Great post, but I disagree with the headline, which suggests closing Convention Center and 7th Avenue. Thankfully, you explain why those stops are needed from the standpoint of calling up pre-empts, the train signals needed to let the train move up to Lloyd Center.

    However, the people suggesting these two platforms should close, are missing the point that these platforms are very needed for those who use it every day. It is not a “simple” walk down to Rose Quarter, or up to Lloyd Center when you are going home from work – or going to work. Also, remember that the Lloyd Center platform is plagued by undesirable behavior, something a lot of people want to avoid, I being one of them.

    Also, as a former rail operator who has gone eastbound up Holladay many times, I can tell you that though the numbers of passengers seem low, the importance to the people who use the platforms is great. Perhaps Portland Transport should find something else of greater importance to be concerned about; this seems rather silly to bring up in a serious manner.

    • Oh I don’t know, I don’t have a problem with Portland Transport commenters brainstorming ideas to improve transit speed downtown. I mean, it takes about 25 minutes for a train to get from Goose Hollow to Lloyd Center, which isn’t a very far distance (considering you can get from Millikan Way to Hatfield, for example, in about the same amount of time). So I understand why they would view that as a hindrance to fast public transportation, especially for people who need to get from one side of downtown to the other which is where MAX is most likely to lose time since it runs with traffic, and therefore look for ways to improve that travel time. But I don’t think there are any rail operators participating in the discussion over there, so I don’t think the commenters are going to come at it from the perspective that you have, or that I have, simply because they haven’t had the same kind of exposure. Which is why I don’t have a problem with suggestions to close stops that logistically couldn’t be closed or that would affect more people than they realize, since it’s probably not as obvious to the general public why those suggestions wouldn’t work.

  3. So my question is, how come the switches couldn’t be thrown at the preceding stop, i.e. the Rose Quarter switches from Lloyd Center westbound and the Doubletree siding switches from Rose Quarter eastbound? I mean, sure it’s farther away, but there are plenty of places on the alignment where you can’t see the switches from the cab and you just rely on the signals, right? Is there some reason this isn’t workable in pre-empt territory?

    • You never “just rely” on signals – you always always always have to observe your switches, since signals can malfunction but switch points don’t lie (I know that’s not what you asked, but that’s just a reflex reaction!) It’s true though – even if 18A tells you it’s safe to proceed, you still need to check all of the switches to make sure that you can.

      Anyway, a few reasons why you can’t select the routes from the preceding stops. You can’t see 20A from Rose Quarter or 18A & 18B from Lloyd Center – they’re already pretty far from 7th & OCC (respectively) as it is. So while it’s true that you don’t see all switches from platforms (e.g. if I’m a westbound Red Line, I’ll get my diverging signal at Sunset & at the intermediate signals, but the switches are way up by BTC), you at least can see the signals to know that you selected with the right route code. There isn’t anything at Lloyd Center to tell you that the switches by Rose Quarter are set for you, and ditto for Rose Quarter & the Doubletree switches.

      Next, ABS/pre-empt combination signals will time out back to reds (all of the ones on Holladay are 60 seconds), but it takes about 4 minutes to travel between Lloyd Center and Rose Quarter – granted that’s with platform stops but I doubt you could make it in a minute even without those stops. So even if you could call 20A from Rose Quarter, it’d be red by the time you got up to 11th, the magnet would be active, and you’d have to stop anyway to reselect it.

      And again keep in mind that it’s really not ideal to stop a train away from a platform. You’ll notice a lot of operators creeping up on red intermediate signals in ABS territory to avoid stopping if at all possible, because passengers are more likely to “redknob” (pull the emergency door release) a train that’s stopped than one that’s moving. It’s a safety hazard if someone redknobs away from a platform, and also time consuming for an operator to call Control, key out, leave the cab, check for injuries if anyone has left the train, walk back to the affected door, reset it, go back to the cab, meanwhile hoping that no one else pulls the red knob during this time. Without OCC & 7th, I could think of a lot of scenarios that would involve trains stopped away from platforms: Whenever there’s a Steel Bridge lift that always backs trains up. And westbound trains are often delayed at Rose Quarter if a Yellow Line is heading into or out of IRQ, and you can’t see into the westbound main at Rose Quarter from OCC but 18A will stay red to keep trains there until Rose Quarter is clear – take away the OCC platform and that’s leaving a train stopped on the mainline waiting for Rose Quarter to clear. Meanwhile, what if their following train at Lloyd Center wants to place a call for the special events track – what’s going to hold them back when the train by OCC hasn’t even crossed the switches into the westbound main yet? And so on…

      That’s not even touching how auto traffic would be impacted by this.

      I understand what everyone’s getting at with the travel time through here since it doesn’t take long to walk the length of Holladay so it seems like a lot of platforms in a small space, but by design all of those platforms really are needed.

      • Something else I just thought of, and would have to double check the signal SOP to verify specifically which ones, but not all of the pre-empts on Holladay are cascaded. Several are called by trailing-car calls (as are a number on Interstate and out in Hillsboro).

    • Also see EMS’s reply below – she got a response out faster than me!

  4. The switches by Lloyd Center are not part of a pre-empt signal system. They have a “chicklet” that will stop the train if the train “runs a red” – it is a combination signal, which means it needs to be called much closer to the switches than the RQ TC would be. There is only so much time (60 seconds, if I don’t remember wrong??) the trains have to get through the intersection at Lloyd Center before the signal times out. And if it times out, it must be “by-passed”, which mean disabling the ATS system on the train for a few seconds to get across the ATS magnet that would normally automatically stop the train. Because of where the cross-over switches are between 9th and 11th Avenue and the intersection of Holladay and 9th Avenue, the trains are not allowed pull back to the 7th Avenue platform due to safety concerns.

    All this means that the signal must be called at 7th Avenue for the travel up to Lloyd Center to be as safe and timely as possible.

    And why change something in this time of great safety concerns about TriMet that is one of the MUST HAVES for train, passenger, pedestrian and vehicle safety in this particular area?

  5. Actually, the idea was to combine the two stations. There would still be a station between the Rose Quarter and 11th Ave switches. And I’m not sure the Convention Center station existed at first.

    But during a Steel Bridge lift, it is nice to have another close place for a train to wait.

  6. Also remember that both the Convention Center and 7th Avenue platforms opened *after* the Banfield alignment opened in ’86. (I think ’88 for the 7th Ave platform and ’90 for the OCC platform, when the new convention center opened, but i might have my history confused on that. Also, the pioneer place stations – 4th & yamhill and 5th & morrison – were also after thoughts and didn’t open until that mall had been in business for at least a year. I still remember when they demolished the Corbett building and riding the train over the big hole in the ground!)

    Operationally, eliminating either of those two stations would be trivial. In the background, however, you are talking about making costly changes to the street infrastructure (i.e. sawcutting for inductive (TWC) loops, changes to programming in the traffic-signal controllers, locating safe “berthing” spots for trains that need to stop to either change course or wait for a leading train, let alone reinstruction for operational personnel – plus what changes would have to be made to standard operating procedures…).

    • If you are who I think you are I’m glad you showed up since you have a much better handle of history of this than me.

      Was 7th after the original opening? I remember hearing OCC was in September of 90 but I thought NE 7th opened with the original Blue Line. That all pre-dates me so operationally I don’t know how this area functioned then.

      • I have three recollections of 7th Avenue. 1st was that it was a planned station, but not originally built (or opened — something); second was that when first opened it was “7th Avenue – Carousel Courtyard” (yes, there were a bunch of wooden ponies in that courtyard for a time); and third was when the carousels were removed and TriMet began it’s lease of the 710 NE Holladay property (and the station name shortened to just “NE 7th Avenue”).

        I’ll look through some historical stuff I have and see if I can nail it down further.

      • Also… remember that Vintage Trolley service did not originate in ’96, so some of those signals may not have been there when the other stations were non-existant (or used).

        I believe the replica Council Crest cars were acquired in ’99. I do believe, however, that the “Red Lion” siding (it wasn’t always the Double Tree!) was built with the rest of the Banfield line, and for sure the vintage trolley barn was at least planned for (I don’t recall if that was built prior to ’86 or after the grand opening…)

        And, one other wrinkle… the current westbound platform used to be reserved for special events; trains didn’t cut over to the right to service the WB platform (with the corresponding increase in wear on the 11C switch points); they went “straight through” and boarded on the left side.

        • I believe you mean ’86 and ’89. And it was better when trains went “straight through” Rose Quarter.

          • Indeed, thanks for the catch.

            I do have some materials that show that 7th Avenue was a “Future” platform, but it does appear that it opened either on time (9/3/86) or within a few short months of opening (as evidenced by the November ’86 timetable linked). I can’t find solid evidence one way or the other, but I do have some coworkers that were around then, so I can ask them.

            I remember the rigamarole (as a rider) about the “Carousel Courtyard” designation being about as high as it was regarding the recent re-renaming of the Civic Stadium station to Jeld-Wen Field Station. (If anyone had been thinking a better option would have been to just ditch the civic naming of the station and call them what they are – Morrison/SW 18th Ave and Yamhill/SW 17th Ave… but I digress.) Anyway, that renaming issue might be what’s got the log jammed up in my memory.

          • Oh… and I agree about the Rose Quarter (remember when it was the ‘Coliseum Transit Center’) routing. (At least that change in name kind of fits the area it’s in. The *arena* name is the “Rose Garden Arena” and it’s next to “Memorial Coliseum”, but the *district* is named Rose Quarter…)

      • According to Wikipedia*, 7th ave was opened on September 5th, 1986, the same date as the original MAX line.

        * Which it’s gotta be true…

  7. I would definitely prefer the original routing for the RQTC platform. I can understand how the current routing is preferable from the standpoint of customers boarding and alighting, but with the tracks and switches as they are, it’s just easier on the equipment the old way.
    As for how Holladay would operate without 7th and OCC platforms, one only need look at how it’s done at Jackson terminus or Hatfield to see how it would be just fine. However, the customers that use that platform every day (and most of those counted in those statistics are probably regulars) would feel strongly about those platforms being decommissioned. The OCC platform provides a great transfer point to the 6 (I knew about this before as a frequent operator of that line), and the 7th Ave platform provides service to several business parks and away from the shenanigans that come with proximity to a mall.
    I’m sure if they were combined somewhere between, neither group of regular riders would object much. Unfortunately, the costs associated with such reconstruction would far outweigh the benefits. We would only be saving a minute, at most.

    • As for how Holladay would operate without 7th and OCC platforms, one only need look at how it’s done at Jackson terminus or Hatfield to see how it would be just fine.

      How so? In that W1760 and M164 come up for you by the time you get there? I think part of the problem of applying that to Holladay is just the sheer number of trains on Holladay, i.e. there’s more likely to be a train between you (westbound at Lloyd Center, for example) and Rose Quarter than there is between me (westbound at Hillsboro TC) and Hatfield.

      I think a lot of this is like the skip-stop idea people often bring up – it would’ve been easier to implement had it been designed that way, but to change things as they are now would be prohibitively expensive, to say nothing of probably being very confusing!

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