02 December 2012

Transbay Update

Early mockup of Transbay layout
Since our previous coverage of Transbay, a gigantic hole has been dug where the old Transbay Terminal used to be.  That's the part you can see.  Behind the scenes, design of the yet-to-be-funded DTX (Downtown Extension) from 4th & King to Transbay continues.  Millions have been spent to bring the design up to "30% engineering" where the details of tracks, stations, and tunnels have been sufficiently defined, down to the inch, to support construction bids and final design.

The TJPA was kind enough to share the latest overview engineering drawing (PDF file) with Friends of Caltrain.  This drawing is marked 'preliminary'.  Sadly, it does not reveal any substantive changes since 2009, and the DTX remains the same slow, 35 mph conflict-ridden mess that it was then.  Where previously it might have earned an overall grade of D, we'll give it a C-minus.  Some improvements were made around the margins, but certainly nowhere near what it could be.  Let's take a closer look.

1. Analysis of an ideal Transbay station interlocking

In the TJPA drawing, the Mission Bay station (built underground and alongside the existing 4th & King terminal) is laid out as in the diagram below.  Inbound traffic comes from MT2 (Main Track 2) and exits on MT5 or MT2, and outbound traffic comes from MT4 or MT2 and exits on MT4.
If we assume that MT4, MT2 and MT5 from a three-track tunnel that feeds the six-track Transbay Transit Center (TTC), we have 3 x 6 = 18 possible routes from the DTX tunnel to the TTC platform tracks numbered T21 through T26 from south to north.  Each of these 18 routes through the interlocking (also known as the "throat" of the station) is labeled by a single letter at the entrance and the exit. In this context, a route is one particular alignment of the tracks, established in the anticipation of a train using it to traverse the interlocking from one track to reach another.
Without getting into expensive simulations, a complex interlocking can be analyzed using a route locking table.  All table elements representing routes that lock each other (converge, diverge, or cross--i.e. conflict, and cannot be simultaneously set without risking a collision) are marked with an 'X'.

To evaluate the performance of the DTX track layout as proposed, we need to compare it to the ideal case, a track layout that cannot be improved upon because it has the fewest possible route conflicts.  If we assume that the entire facility must remain on one level (with no tracks passing over or under each other) then conflicts necessarily occur between any route that crosses over another, for example routes f and m in the diagram above, or routes that share a portion of track, such as m and n.  By inspection of the diagram, we can construct the ideal route locking table below.

Ideal route locking table for Transbay
This is the most conflict-free this interlocking design can ever be, and illustrates why stub terminals are avoided whenever possible.  234 out of 324 possible routes (72%) conflict with each other at best, so we would like a Transbay design that doesn't make an already bad situation even worse.

The route locking table can be improved (representing the pros and cons of various layouts more realistically) by weighting each route combination by the number of trains it carries, because we don't care if seldom-used routes happen to conflict.  Instead of filling each cell of route locking table with an 'X', we compute a weight that represents the relative frequency of route combination a,b as n_a * n_b / N^2, where n_a is the number of trains using route a, n_b using route b, and N the total number of trains.

The weights for the current Transbay design are computed by recalling that all Caltrain traffic is routed to/from platform tracks T25 and T26, while all HSR traffic is routed to/from platform tracks T21 through T24.  Furthermore, MT5 is intended for inbound traffic, and MT4 for outbound traffic.  MT2 is used more rarely to relieve congestion.  For the "blended" system planned for 2029, let's assume the following traffic levels in trains per hour:
  • 6 inbound Caltrains, 4 of which use MT5 and 2 use MT2 to get out of the way of HSR
  • 6 outbound Caltrains, all of which must use MT4 to serve Mission Bay
  • 6 inbound HSR (of which 2 are dead-head moves with no passengers), using MT5
  • 6 outbound HSR (again with 2 dead-head moves), 4 of which use MT4 and 2 use MT2 to overtake Caltrain at Mission Bay.
Out of those 6 x 4 = 24 movements per peak hour, ten use MT5, four use MT2, and ten use MT4.  Distributing that traffic to the corresponding platforms, we obtain the traffic-weighted route locking table for the "ideal" interlocking, subject to non-ideal platform segregation per TTC plans.  Because of this segregation between HSR and Caltrain platforms, each route is used exclusively by HSR (shaded in blue) or exclusively by Caltrain (shaded in yellow).

Ideal route locking table, weighted by traffic
The sum of each row or column is a measure of how conflict-prone each route is.  It comes as no surprise that the worst actors are routes q and r (because of high outbound Caltrain traffic) as well as e and f (because Caltrains inbound on MT5 must cut across the entire interlocking to reach their assigned platforms).  The 0.70 route locking rate means that two typical routes through the interlocking will conflict 70% of the time.

This implies the best Transbay track layout that can ever be designed will allow two trains to simultaneously move into or out of the station without regard to each other only 30% of the time.  Timetable planners and dispatchers will have their work cut out for them even on a good day.

2. Analysis of the Transbay station interlocking as designed

Inspection of the latest DTX track layout shows that it is configured like so:
The dotted lines show two curved 'emergency' crossovers, known as XO-201 and XO-202, that were provided in response to Caltrain's request for emergency operational capacity.  They will be used only when a failure occurs, and not during normal operations.  Without those crossovers, Caltrain was one failure away from total shutdown.

What immediately jumps out to a casual observer is that each pair of platform tracks (T21-22, T23-24, T25-26) necks down to a single turnout, preventing simultaneous routes from being established on both sides of the same platform.

By inspection of the DTX layout, one can draw up the traffic-weighted route locking table below.
As-designed route locking table, weighted by traffic
The cells highlighted in orange are those that differ from the ideal layout discussed previously.  The route locking rate has increased, to 0.75.  The unused emergency crossover XO-202 single-handedly accounts for 0.03, the lion's share of the increase.  The free-route rate of 0.25 is down from 0.30 in the ideal case; in other words, the probability of a conflict-free route is 17% lower than for the ideal layout.

For an already constrained and inherently conflict-prone stub terminal, it is unacceptable to make traffic jams even worse than they need to be, and yet that is precisely what the proposed DTX track layout will do.

The simplest improvement to be made is to add crossovers in the curved throat where the DTX enters the train box, to enable simultaneous and conflict free movements to/from opposite sides of the same platform.  This achieves the lowest-possible route locking rate.  The Caltrain curved crossover, XO-202 connecting tracks T25 to T24, is the most important one of these and needs to become part of normal operations.  Two more curved crossovers need to be added to allow simultaneous movements to reach HSR platforms.  The three missing crossovers are shown below.
DTX track layout with three crossovers added to achieve "ideal" route locking rate
Better yet, the Caltrain and HSR platforms should be desegregated to give dispatchers the flexibility to avoid conflicts when they do threaten to arise.  The route locking table gives the likelihood that any two randomly selected routes will conflict, but if a dispatcher can send a train to any platform or track, such conflicts can be avoided completely.

3. Another problem entirely: interlocking length

Route conflicts are one problem, but not the only problem with the DTX design.

When a train occupies the station "throat" interlocking, the duration of that occupancy must be minimized so that those conflicts that do inevitably arise (especially during off-timetable situations) are as short-lived as possible.  This conflict duration depends on the signaling system (through such parameters as route setting time, signal watching time, approach time, clearing time, and release time), and also on the time when the train physically occupies the interlocking.  This we can do something about; it is related to the length of the train, its speed, and the length of the interlocking.

As currently designed, the throat interlocking extends over a considerable distance from the TTC train box all the way down to Bryant Street. The November 2012 plans show the interlocking stretching from STA 148 to STA 173, a length of 2500 ft or 750 meters.  The speed is constrained at both ends, 35 mph at the south end and 22 mph into the train box.  We can take 29 mph or a nice round 13 m/s as a realistic average speed through the interlocking.

The physical occupancy time for one train is equal to (train length + interlocking length) divided by speed.  To this we can add 30 seconds of route clearing/setting time, and 30 seconds of approach time after the route has been set but before the train enters the interlocking.  For example, a 400 meter train moving at 13 m/s through a 750 meter interlocking will tie up a route for (400 + 750) / 13 + 30 + 30 = 148 seconds.

Using the assumed traffic levels as well as train length parameters below, we can run a simple randomized trial to quantify the relationship between throat length and the cumulative duration of route conflicts.  For each trial, the timing of train arrivals / departures is randomized over one hour (admittedly a worse assumption than reality, where conflicts are avoided by adhering to a timetable) and the total duration of conflict between routes is computed, after applying the route locking factor to account for routes that are mutually compatible.

Here are some realistic parameters for the "blended" scenario planned for 2029:
  • Caltrain train length: 180 m
  • HSR train length: 400 m
  • Speed through interlocking: 13 m/s
  • Caltrain movements: 12 per hour
  • HSR movements: 12 per hour (including 4 dead-head movements to/from yard)
Effect of interlocking length
on average route conflict duration,
over the span of one hour
As can readily be observed in the graph at left, the relationship between the typical cumulative duration of conflicts and the length of the interlocking is strong, which implies that making the interlocking as short as possible will (a) facilitate the construction of a workable blended timetable by allowing closer spacing between train movements, and (b) facilitate timetable recovery after something goes wrong by reducing the cascading effect of delays in the station throat.

Note that things will get exponentially worse if traffic increases, as it may in the long-term horizon beyond the blended system.

As currently designed, the layout of the Transbay interlocking betrays little or no attempt to minimize overall length.  The resulting length of 750 meters is grossly excessive; it can and should be reduced to less than 400 meters.  A shorter layout for the interlocking would dramatically reduce route conflict duration--by fully one third compared to the current design--even if it requires the use of #10 turnouts and more turnouts and crossovers in the curved portion of the station throat, where the design speed limit is just 22 mph.  Why not take advantage of this tight speed restriction to do the dirty business of routing trains to the correct track?

This solution isn't obvious to American designers because it requires the use of non-standard track elements that may be considered exotic under typical U.S. freight rail AREMA standards, such as slip switches, curved turnouts and curved crossovers.  Indeed, this prejudice explains why the curved crossovers in the DTX design are usable only in emergencies. While designing "by the book" is always a safe option, it is unfortunately not feasible to engineer a compact throat layout for Transbay using standard turnouts.  Unlike the 100-ton coal hoppers with worn wheels anticipated by AREMA standards, this facility will only ever serve trains with very light axle loads, and maintained to the most exacting specifications.  Much of the conservatism and design margin built into AREMA standards is completely unwarranted for Transbay, and inevitably leads to a mediocre layout.

4. Conclusion

Transbay will be a special station, probably the most valuable piece of rail real estate west of the Mississippi.  As an inherently constrained stub terminal, it demands excellence in design to achieve the highest possible capacity. While the current track layout may be deemed adequate for the blended Caltrain / HSR scenario planned for 2029, the twin failings of unnecessary route conflicts and excessive length will rapidly reveal themselves as fatal weaknesses when traffic demand increases or minor incidents throw timetables into disarray.  Such entirely avoidable self-inflicted delays will cause excess traffic to be diverted to 4th & King, a terrible outcome for passengers as well as the economic vitality of the TTC and the city of San Francisco.  Minor changes to the DTX track layout can address these failings.

44 comments:

  1. Thanks Clem, very clear and informative. Had you proposed an alternate throat design that reduces interlocking conflicts and interlocking length?

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    1. There are a million ways to do it, which is why it's less interesting to prescribe a point solution than to point out which requirements aren't being met.

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    2. Actually, there aren't a million ways to do it. More like one, with minor variations. And believe me, I spent thousands of hours trying alternatives.

      Note also that I use track geometry standards from a modern industrialized first world democracy with a functioning public transportation sector, as opposed to PTG, TJPA and PCJPB's "engineers', who pulled their own globally-unique "standards" out of their own orifices and then claim that they were rather handed down from Moses on stone tablets.

      (What I use: 190m exceptional, 200m ruling minimum curve radius, standard EU turnout geometry, inner-cuved turnouts with 1:12 500m radius base geometry bent to the maximum allowable 333m (outer) and 200m (inner) radius. All straight out of the DB design standards. If one wishes to fit 400m straight-ish platforms and a 200m-ish radius curve in the ~600m between the buildings lining Main Street and Second Street one runs out of choices quick smart.)

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  2. It seems to me that what you are proposing for DTX is an optimal Western European style design given the physical constraints. But we must remember that Western Europe does not have a monopoly on effective railway design. Given the problem at hand, I wonder what a Japanese engineer would propose?

    I have very little experience with railways in Europe, but I have ridden many trains in Japan and the efficiency is breathtaking.

    Japanese railways seem to achieve their efficiency and reliability largely through simplicity. Station throats have very few turnouts by western standards. Specific trains and services are nearly always assigned to specific tracks and specific platforms, instead of spec'ing out their systems as "Any train, any track, any direction, any time", tracks do not even have bi-directional signals. Interlockings for redundancy, failure recovery, or "future proofing" are kept to a minimum.

    Reading this blog post (don't remember where I found the link; it may have been one of your earlier posts!) proved quite educational to me.

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    1. Interestingly, the Tokaido Shinkansen gets by with each set of three platform tracks feeding into a single mainline track and one double crossover in Tokyo. Of course, this is with Japanese operational practices and punctuality standards which are nothing short of a pipe dream here.

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    2. Yes, passengers want predictability, and dedicate platforms for different lines, is desirable once certain frequency is reached. This also led to simplified turn-out designs and thus simplified operations. Fewer components to maintain is also an advantage, even American cannot fail to see that.

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    3. Passengers do indeed want fixed platform assignments.

      But given the SF Transbay combinations of a severely under-sized station (due to the disastrous LPA, then subsequently crippled by self-inflicted mis-design), with catastrophically (100% self-inflicted) bad passenger circulation, and terrible train schedule adherence (no level boarding guarantees this, regardless of anything else), this is wishful thinking.

      Especially given only two platform faces for Caltrain in the PTG/TJPA/PCJPB "design", the inevitable service disruption "alternative" is to terminate trains at an entirely different station, rather than move them onto a different platform track at Transbay, How predictable and desirable and simplified is that? It is simply inconceivable that any of the morons responsible could be allowed to hold down a Burger King job, let alone be paid multiple hundreds of millions of tax dollars for their "engineering" "expertise".

      "As simple as possible, but not simpler" and all that.

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    4. Michael Schaeffer15 December, 2012 19:00

      Can the passenger circulation be fixed? What can be done? There's still time.

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    5. No. The civil structure of the building -- the columns holding up the Big Bus Station in the Sky with a Park on Top -- were fixed, essentially on the back of a paper napkin, with no consideration whatsoever of the transportation function of the building almost a decade ago. Seriously: somebody from ARUP came up with a column spacing (in feet and inches, of course) for a paper-napkin 1% design that blocked out the space available, and it has never changed since. The "architects" who won the "design" "competition" certainly never touched that.

      The support columns do no line up with the train platforms (the trains in the basement being an afterthought extra hidden layer, never mind about them!), and the columns are so large (5 and 6 foot diameter), uniformly circular (not allowing pairs of escalators and/or stairs to pass beside them) and so closely spaced that there is no way for pairs of escalators of elevators to reach the platforms.

      The entirely superfluous and useless and costly mezzanine level exists solely to impeded passenger circulation and will not be discarded, because extra cost and more fucked up passenger experience = WIN for America's Finest Transportation Planning Professionals.

      The complete lack of circulation from the mezzanine level towards Mission Street (north, the direction in which 90% of train passengers will wish to travel) will not be corrected. Instead, they must travel via the "Grand Hall". Because fucked up routes and congestion and delay = WIN for America's Finest Transportation Planning Professionals.

      Good luck fixing this -- or the catastrophic track alignment, and the non-interchangeable platforms with Caltrain locked out of 2/3 of the station, or the truncated-length platform -- in the "time" that "still" exists. The only thing that can fix this is the the TJPA and PCJPPB and everybody in any way connected with the project to be terminated immediately with maximum prejudice. It's completely hopeless. They are, uniformly, sub-morons who are not even capable of awareness of how utterly, totally, completely, irremediably incompetent, ignorant, unqualified, unprofessional, and stupid they are.

      PS But don't worry, it's not just the rail service that can never work at Transbay: the Big Bus Station in the Sky is almost equally fucked up! Consider this: every bus into or out of the terminal will be required to stop at a stop sign where the inbound and outbound lanes cross at grade, despite the $4 billion price tag of the project, and despite the fact that the lanes are vertically separated on the Bay Bridge. The bring inbound and outbound down to the same level, then have them cross each other in order to have counter-clockwise circulation within the Big Bus Station in the Sky. Sheer genius! Unparalleled expertise! You can thank Tony Bruzzone, once of AC Transit, now an ARUP rent-seeker, for this particular piece of brilliance. (You can also thank Bruzzone for the outright rejection of any real LPA analysis of the rail alignment. Stand-up guy!)

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    6. Adirondacker1280016 December, 2012 12:07

      Penn Station of the West? With the Port Authority Bus Terminal hovering over it!

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    7. We can say that the structure is physically unsafe. That it needs to be redesigned. Of course, the videos on the website show a platform level that looks fine. Besides Richard, why don't you draw us what you think the passenger circulation should look like at Transbay. Oh, and I'm gonna have a little chat with this guy you've mentioned.

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    8. The columns could be shortened and redesigned. It shouldn't be too hard to fix a problem if it's pointed out repeatedly that it's unsafe.

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    9. Richard: what this proves is that consultants will get away with laziness if the elected officials who are supposed to oversee them don't give a damn.

      And that in SF, they don't give a damn.

      There is a series of *more than 12* articles in the SF Weekly by Joe Eskenazi about the rotten culture of SF governmental institutions. http://www.sfweekly.com/authors/joe-eskenazi/

      Now, LA has a rotten *police* culture, but its *infrastructure* culture is actually pretty healthy -- so I'm feeling a lot better about the CHSRA now that LA people are in charge.

      In SF? Well, nothing's gonna get better until the city has a cultural change, a change in priorities, and I don't see what will make that happen. Most people in SF think the city is wonderful the way it is. (In contrast, I can see exactly what will change LA police culture. Most people find it obnoxious and want to stop it.)

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  3. Great article Clem, two questions:
    1) Can you clarify why there are 4 dead-head HSR trains per hour? I'd expect some dead-heading in the start of the morning and end of evening to park trains overnight from Bayshore, but you make it seem like it's a continual affair.

    2) Is it possible to add mid-platform crossovers to the Transbay station platforms for Caltrain? You could split the Caltrain platforms T25 & T26 into T25a, T25b, T26a and T26b. While not as good as giving Caltrain more platforms, you could now park and board up to 4 trains simultaneously. You could also shave some time interlocking switching & clearing time by dispatching trains from the same platform right after another.

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    1. 1) it will be a fairly continual affair, because the peak duration is on the same order as a one-way trip from SF-LA. There isn't time for trains to show up and turn around immediately-- by then the peak is already over.

      2) take a look at the drawing, and your answer will be obvious.

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  4. What I appreciate about your blog is that I find your examinations and explanations of these issues to be extremely accessible to someone like myself who is not an engineer and only recently developed an interest in this subject. My continuing problem now is failing to understand why these seemingly "obvious" conclusions continue to be overlooked by the persons tasked with making this system work. In this case, your proposal to add connecting track and move the track switching to the curved portion of the throat seem eminently sensible, and have been proven to work throughout Europe. I find the idea that dogmatic thinking alone explains why these solutions have not already been seized upon to be a bit bizarre. Are we really so behind and so blind to foreign advances even as we try to emulate their success? Or is there some hidden profit in the track layout as currently planned?

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    1. Because the designers are US engineers, who by definition, have served an apprenticeship with other practicing engineers. And the _only_ practice in rail enginereing in the US in the last few decades, has been freight rail.

      Design of from-scratch passenger terminals seems to be a lost art within that community. Proof by example: Clem, or Richard M, or I can design a better station throat.

      My instinct is to move Clem's MT4-MT2 crossover toward the platforms, platform-side of the MT4-MT5 crossover, which gives more flexibility in case of turnout failures. but I confess I haven't even thought of building a route-conflict table for that. It would let one replace the MT2/MT4 Hosentraeger/scissors-crossover with a simple cross-over in the opposite direction to the crossover I want to move -- which would result in a more classical German-speaking station approach.. approach crossovers from one side all the way to the other side; and downstream crossover from that side, all the way back to the far (original-side) platform track. But I digress; 'nuff said.

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    2. The twin goals of transportation utility and cost-effectiveness are evidently not on the top of the agenda, considering the way the Bay Area transportation industrial complex has evolved over the last few decades. That's why appeals to either of these goals usually fall on deaf ears. DTX, BART to SFO, the Central Subway, Oakland airport connector, BART to SJ, CBOSS, etc. achieved (or are on their way to achieving) the same world-class level of mediocrity.

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    3. Note that LA area passenger terminal designs are, although not ideal by world standards, operationally decent. There really is an SF / Bay Area cultural problem.

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  5. Excellent post as always. What do you think of the viability of deep tunneling the DTX? Green Caltrain linked to a presentation on the subject.

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    1. There are no doubt ways to do it, but I was shooting for minor adjustments to the existing plan that wouldn't require flushing tens of millions of design work down the toilet to start over from scratch. Maybe a different future blog post...

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    2. In the end I'm kind of expecting a deep tunnel solution anyway. The Transbay Terminal is being horribly botched to such a spectacular degree that it just won't work. The next step will be a new Transbay Tube, which everyone knows is needed anyway. Meanwhile the sea level will be rising. Assuming San Francisco remains rich, it will seem easiest to go in a broad curve, put a single mined platform somewhere deep under Market Street, and head to Oakland.

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  6. One way to reduce the length of time routes conflict is by using sectional route release, where the route segments behind a train are released as sson as the train vacates them and can be used for another route. Fortunately, Caltrain is actually aware of such things, and will hopefully implement that here, where it might help. Another possibility is more intermediate signals in the interlocking. But those are only marginal gains, giving at best a few second here and there, which can help with an optimized layout, but not necessarily here. I'm kind of curious about the aversion to curved switches though. I know Amtrak uses them in various places in the Northeast, including in the Zoo interlocking in Philadelphia but also in a few higher speed locations as well.
    The comparison of the Tokyo terminus of the Tokaido Shinkansen is quite instructive, by the way. The interlocking is very compact, with something like 230 meters from the end of the platforms to the far side of the double crossover. The geometry doesn't seem very restrictive either, which might help with train speed, but I don't know what the speed through the switches is in either direction. I imagine they can also get some benefit by carefully timetabling trains for minimal conflicts, and then keeping the timetable to a precision of seconds. It'll be a lot harder to do that with the constraint that all Caltrains have to arrive at the Caltrain platforms, and the random delays that Caltrains tend to suffer currently.

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    1. Well, if the problem really is "Caltrain can't keep a schedule," then the important thing is to spend a bit of extra money on changing that. Caltrain is the primary user of its tracks, the minimal existing freight can be kicked out if it's that big of a deal, and HSR running on its own tracks is very punctual so it's not going to foul up the schedule.

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    2. There is little to no freight during the day. If CalTrain can't keep on schedule, it's CalTrain's fault, or maybe the fact that the equipment and stations suck at getting passengers on and off of trains.

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    3. Alon,
      In point of fact, today, Caltrain _cannot_ keep a schedule. They have to deal with regrettably frequent fatal accidents on at-grade crossings, which cause horrendous delays -- hours or more. Equipment reliability is currently a problem, too.

      Even if the grade crossing were fixed anytime someone in a wheelchair tries to board Caltrain, adherence to the WW2-era regulations in California Public Utilities General Order 26-D (CPUC GO 26-D) ensure that Caltrain _cannot_ keep to a schehdule. CPUC GO 26-D mandates and crazy "mini-high" wheelchair ramps with a clearance envelope which precludes quick boarding. Thus, any wheelchair passenger necessarily requires significant conductor assistance. So unless you budget 3 to 5 mins for every single scheduled stop there is _no way_ Caltrain can get decent on-schedule performance.

      Level boarding would fix that. But getting level boarding is a _regulatory_ issue, more than a money issue. (The money issues wont' even be broached until the regulatory issues are fixed). I can only hope that HSR train-sets will force something to be done about that.

      I do hope I'm not sounding like Richard M....

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    4. How difficult to get waiver for CPUC GO 26-D? It is more difficult to get waiver of operating Non-FRA trainset?

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    5. We don't know how difficult it would be because no one (by which I mean CalTrain) has even tried.

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    6. Caltrain wheel chair riders at stations without mini-high platforms add roughly 2 minutes to dwell times whether boarding or alighting. At least one observer noted in a TCRP report that on a transit system with station platform levels even with train floors that wheel-chair riders actually took less time to move across train thresholds than riders able to walk.
      The near term electrification of Caltrain with the replacement of most rolling stock appears to be a good time to construct a level-boarding-system. The California Public Utilities Commission’s platform height restrictions next to freight train tracks should be handled by one of two ways:
      (1) Eliminate freight service between Santa Clara and San Francisco allowed under the operating agreement between the Southern Pacific and the Peninsula Corridor Joint Powers Board as part of the original sale agreement under one condition. If the PCJPB wished to implement a rail technology incompatible with the continuation of freight service.
      (2) Divert San Francisco bound freight trains over the Dumbarton Rail Bridge and down the center of the 101 freeway to South San Francisco. Note: There are no stations to interfere with legal freight operation along the 4.1 mile long right-of-way between the South San Francisco and Bayshore Stations. A 101 Freeway center track would be remarkably flat except for one bridge across Woodside Road. This approach might accommodate double stack, high cube, and automobile carrying freight traffic without time restrictions; an important flexibility for high value freight. The considerably faster transcontinental freight schedules in recent years should increase the profitability of a high-value peninsula freight service extension.
      (3) A suggestion from a CPUC engineer to place gauntlet tracks through every station in order to accommodate freight train passing through level boarding platform stations should never be considered. The addition of nearly 100 switches in order to conform to a safety rule of questionable efficacy would result in a sharp reduction in overall rail-system safety. There have been many train-wrecks involving switches including the world’s only serious hsr wreck that occurred in Germany a few years ago. (In that particular case a wheel’s rail contact surface disintegrated and derailed. The train stayed largely parallel with the rails until the derailed section struck a track-switch and slewed across the right-of-way destroying an over-crossing bridge support. The bridge structure subsequently collapsed onto the moving train causing the loss of 98 lives.)

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    7. This is ridiculous. There's no need to build any additional infrastructure, even if you want to accommodate freight. Freight trains pass high platforms all the time all over the world (even in this country) and there are no issues. The CPUC regulation is a holdover from another area which isn't at all relevant to even freight traffic in this day and age. You would have an issue if the CHSRA or CalTrain intended to use UIC loading gauge, but as it stands now it looks like they plan to take full advantage of Plate F's additional width. So limit freight to nighttime operations, limit axel loads to save on structures and maintenance, prohibit double stacks (not that they can run now anyway). It's not that difficult.

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    8. Watch this video filmed in Ossining, New York, showing a freight train flying right past high platforms. This is one of many examples. It is not crazy to do this.

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    9. Amazing!!!

      That wouldn’t happen here, I have seen the Bozos in San Francisco get all pushed out of shape if someone is on the platform while a Caltrain is arriving or departing, even to the point of the brain-dead transit police threatening the person with a citation. Quite a few years ago, in Los Angeles/LAUS, they would not allow me and 2 others watch/take pictures of trains arriving/departing from the platform.

      BTW….

      Where is the guy hanging off the side of that freight train???

      Remember, all fright trains have to have a crewmember hanging off the side of the train….

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  7. O/T does anyone know that the status of CalTrain's report on additional service under the Blended plan (including possible express trains) is? It was originally planned to be released in late summer, then that changed to early fall. But it's now December and it's still not out.

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  8. @Joey I got another Real Soon Now on Wednesday fwiw.

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  9. Given the self-inflicted errors in the Bay Area, LA Union might end up being more valuable real estate.

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  10. RE: " Consider this: every bus into or out of the terminal will be required to stop at a stop sign where the inbound and outbound lanes cross at grade, despite the $4 billion price tag of the project, and despite the fact that the lanes are vertically separated on the Bay Bridge. The bring inbound and outbound down to the same level, then have them cross each other in order to have counter-clockwise circulation within the Big Bus Station in the Sky."

    Is this really true?
    The RFQ (http://transbaycenter.org/uploads/2013/01/TG18-1_RFQ.pdf ) says:

    "Bus Ramps: Scope includes elevated roadways connecting the Elevated Bus Level with the San
    Francisco-Oakland Bay Bridge and with bus storage under the Bay Bridge’s West Approach structure.
    These ramps will approach the TCB from the south and connect to the TCB at the southwest corner.
    The construction of the Bus Ramps is the focus of this RFQ. "

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    1. Yes. It is true.

      I'm one of the few people who doesn't say anything when he doesn't know what he's talking about.

      All inbound and outbound buses cross at grade from right-hand to left-hand running at an "X" on a single level bridge between the lines of Tehama and Clementina Streets.

      A quick web serach "Transbay Terminal bus ramps ARUP" turns up this example dated December 2012.
      http://www.actransit.org/wp-content/uploads/board_memos/1_12-248%20TTC%20Project.pdf (typical idiot low-res PDF scan of a PDF original, but you get the idea.)

      America's Finest Transportation Planning Professionals: death is too kind a fate.

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    2. That is pretty appalling... they couldn't do a little whoop-dee-doo flyover ramp? Maybe they got too absorbed with the design of the cable-stayed portion of the ramp, a choice of bridge type that conforms to the same form-follows-function ethic as the Bay Bridge east span. Then again, more time will be lost on escalators than stopping at this new ramp traffic light. I should like to contemplate this in my roof garden.

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    3. Richard, you do say things when you don't know what you're talking about, and we've caught you doing it on previous occasions.

      Of course, you are dead right about this. The Transbay Terminal is the most unbelievably botched design ever.

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    4. What the hell is a "semaphore arm" doing here? Is this supposed to be like a crossing gate?

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  11. I'm sure all this makes perfect sense, but all we need to do is build the HSR terminal at 4th and King. The Transbay Terminal was never meant for HSR, and most HSR passengers will not need access to the financial district. Yes nice if a couple of early morning trains could make it there, but the financial district is a local market for Caltrain. What HSR passengers need is space, amenities, time and connections (that includes taxis). The 4th and King location "only" lacks a good BART connection. As the current constraint on BARTs peak capacity is the downtown stations, perhaps a parallel downtown line going to 4th and King (as opposed to additional platforms downtown) is a solution to a number of issues?

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    1. The BART connection to HSR is at Millbrae. Direct connection, unlike the TBT, which is a couple of blocks away from Embarcadero BART. Has the added advantage that, unlike Embarcadero, HSR passengers arriving at peak commute times and boarding BART won't have to cram into already full trains. And a HSR station at 4th and King might give the Central Subway something useful to do.

      I don't really understand the need for HSR at TBT either. LA Union Station is about as far from LA's financial district as 4th and King is from San Francisco's, and nobody's suggesting there's a desperate need to scrap it and build a massive station under Bunker Hill.

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