Sunday, April 5, 2009

Transbay Terminal Redux

NOTE: We've moved! Visit us at the California High Speed Rail Blog.

Heads Up: Neighborhood meeting on HSR for residents of the Willow Glen neighborhood in San Jose, on Wednesday, April 8 at 1292 Minnesota Ave from 7-9pm. Resources at the end of this post.

The fair city of San Francisco has probably had more than its fair share of coverage on this blog. In just the past couple of months, we've already had quite a few posts recently on the controversial new Transbay Terminal Center (see posts 1, 2, 3). In addition, Clem Tillier has published a post on the Focus On: SF Transbay Transit Center on his Caltrain-HSR Compatibility Blog.

So why revisit this issue yet again? Well, because Quentin Kopp is once again saying that 4th & King would be good enough for him - knowing full well that this will unleash howls of protest from SF city officials and residents, in no small measure because CHSRA consistently marketed the starter line as going from downtown San Francisco to San Jose Diridon, LA Union Station and Anaheim ARTIC.

Note, however, one flaw in the snippet from the Examiner: supporting a five-minute headway on the HSR line down the peninsula is not quite the same thing as actually running a train literally every five minutes. It just means that the signaling and other technology has to cope with an HSR train following another within the space of five minutes, something that may well happen at certain times in a timetable supporting multiple service classes (e.g. express, semi-express, semi-local, local). Recovery from unexpected delays and other off-design conditions may also require operators to minimize headways at certain times. Safe operations of sections of a line with moderate speed limits are possible with as little as 2.5-3 minute headways, so 5 is actually conservative.

The number of platforms is a potential issue a number of decades down the road, maybe. On the other hand, the poor design of the connection between the DTX tunnel and the platforms, the so-called "throat", is a real issue right now because Caltrain will also use the tunnel and downtown station. It's a bottleneck even an expensive three-track tunnel cannot fully resolve. Moreover, according to Clem, the current design of the DTX tunnel features curve radii so small that they effectively preclude the use of Japanese shinkansen train designs for the California system.


The current design features 6 long platform tracks, some slightly curved, accessed via three-track tunnel out to Caltrain's existing 4th & King terminus station. The six tracks would be accessible via three island platforms, one for Caltrain and the other two for HSR. The split is partly a result of Caltrain's decision to stick with low platforms even at the Transbay Terminal, where no freight train will ever go.

The reason for the ongoing brouhaha over this one station is really quite simple. CHSRA has raised a very late red flag on the design of the DTX tunnel and train box, claiming it does not support the 12 HSR trains per hour (tph) each way that he thinks it should support, in addition to the 10tph Caltrain is hoping to run during weekday rush hour in 2025. I've argued that (a) any sane operator would anyhow choose to terminate some HSR trains further south long before reaching 12tph and, (b) that four platform tracks is anyhow enough for 12tph if you enforce some pedestrian flow control.

Tellingly, the red flag came - or rather, was shown in public - only after the Transbay Joint Powers Authority (TJPA) decided to apply directly for a slice of the HSR funds in the stimulus bill, rather than route that request through CHSRA. TJPA had previously been under the impression that 4tph would be sufficient for HSR operations. While that's true for the early years, perhaps even for several decades, CHSRA thinks its job is to deliver an infrastructure with enough capacity for the next 50, even 100 years. There is some method to that madness, as expanding a constrained downtown station decades after initial construction is usually extremely difficult/expensive or downright impossible.

While the timing suggested a political motivation, there does appear to be a real problem after all: the so-called throat, in which the six platform tracks have to converge to the smaller number in the tunnel, is very tight and by all accounts poorly designed. It constrains throughput for no good reason, Clem included a much improved version designed by Richard Mlynarik in his post.

Still, with a minimum curve radius of just 150m (~500ft), even Richard's improved version would effectively preclude the purchase of proven, off-the-shelf Japanese high speed trains - those need at least 280m, preferably more. SF real estate development should not drive HSR vendor decisions with statewide implications. To my mind, this is a red flag well worth raising - though CHSRA could and should have done so much sooner and publicly if TJPA was dismissive of this particular issue.

Station Requirements

Like any building, the aesthetics of the Transbay Terminal have their fans and their detractors. You can't argue about taste. What matters more to transportation engineers is functionality, which the current design might meet, sort of, for both CHSRA and Caltrain, but only after some modifications.

I've thought about this some more since my last post on it and have come to the following conclusion: the train portion of the design is suboptimal because planners interpreted the intent of SF voters (prop H, 1999) very narrowly as bringing the trains into the building itself. However, nobody except the developers really cares about that. IMHO, the voter intent was that the trains should stop within walking distance of the financial center, preferably also close to the bus terminal and such that an option of a second transbay tube to downtown Oakland is created.

If you subscribe to this more liberal interpretation, it is no longer essential to run tracks into the basement of the Transbay Terminal building. Rather, the focus can shift to a design that better meets the requirements of modern railway operations:
  • large platform number (more than six)
  • no platforms dedicated to any one operator
  • all platforms full length (400m, i.e. 1/4 mile)
  • all platforms straight
  • all platforms level boarding (see Caveats below)
  • high pedestrian flow capacity between trains and city streets
  • minimum curve radius 280m (vendor flexibility, screeching noise)
  • minimal cross-blocking of trains entering and exiting the terminus station
  • all platform tracks run-through if second transbay tube is ever constructed
Train Station Under Mission Street

Fortunately, it's actually possible to meet these requirements in San Francisco, though it requires divorcing the design of the Transbay Terminal building from that of the railway station. The two would be linked via city streets, possibly a short underground pedestrian passage. If that's good enough for linking to BART and SF Muni subway, why the absolute requirement to put standard gauge trains into the basement? The upshot is that the Transbay Terminal should go ahead as planned, but without a train box or concourse level.

The following map and topology diagram show the concept I've come up with: a Central Station for San Francisco underneath Mission Street. Detailed design and construction would be far from trivial: many SF city buses use Mission to reach downtown, so tearing open that street would be quite disruptive during construction, even if it is done one block at a time. In addition, the street is quite narrow, around 85 feet including both sidewalks. That's only enough room for three tracks, two side platforms and narrow escalators/flights of stairs - which implies a lot of those would be needed to secure sufficient pedestrian flow capacity. Finally, there is almost certainly plenty of plumbing, ancient sewer mains, power mains etc. lurking underneath street level.

View Larger Map

Tunnel Route

The first thing you'll notice is that the DTX tunnel runs down 7th and Mission Streets, a very different route from the one currently proposed. I'm advocating just two tunnel tracks side-by-side, shared by non-compliant HSR and equally non-compliant Caltrain EMU trains, protected by appropriate signaling. Any legacy FRA-compliant trains need to terminate at 4th & King anyhow, since they're diesel-powered. Nevertheless, track sharing is only possible if FRA approves both Caltrain's request to switch to non-compliant EMUs and CHSRA's intent to buy proven, off-the-shelf but non-compliant bullet trains capable of cruising at 220mph.

One fringe benefit of the changed tunnel route is that no platform tracks are lost at 4th & King. Only a single 90 degree turn is required, in an area where real estate is probably less expensive than in Rincon Hill or downtown. In combination with the less complex excavation methods required for two single-track curved tunnels, this ought to permit a sufficiently generous curve radius. The map shows the maximum feasible radius of ~325m, there are various length constraints along Mission Street. A more detailed design would seek to optimize the radius as tunneling under existing buildings is expensive. Note that I have assumed the curve would be level; a helical curve would permit gradients of less than 3.5% in the vertical elevation change sections at either end.

My point is that the radius can be made large enough even for off-the-shelf Japanese high speed trains. This also eliminates any screeching noises from the long-wheelbase trucks required for stability at high speed. Crucially, it also increases station throat throughput because speed limits are proportional to the square root of curve radius. With appropriate tracks superelevation, it should be possible for outbound trains (non-tilt types) to take this corner at speeds as high as 60 mph, assuming the curve radii and speed limits for the various points along the way also have appropriate values.

The design objective should be to permit a train to pull away from any platform at maximum acceleration (~1.1 m/s^2 for Caltrain locals) and maintain that until it either hits the speed limit or has cleared the station's outer throat, i.e. the point at which tracks from the two levels converge. The minimum available distance for acceleration is about 1/2 mile, though trains on the lower platform face a 3.5% uphill climb for half that distance. Either way, any given Caltrain leaving an east platform should be able to clear the inner throat near 3rd Street within 75 seconds and the outer throat within 120. Maximum acceleration for HSR trains is more like 0.6-0.8 m/s^2 so they may take a little bit longer. Note that an incoming train may proceed past the outer throat as far as the inner one while a train is emerging from the same level; this provides a 15 second buffer.

Conclusion: as long as the curve in the access tunnel can be taken at fairly high speed, the elongated nature of the station layout does not appear to present a throughput bottleneck since the maximum time required to clear the outer throat is still less than the absolute minimum time separation imposed by the two-track access tunnel, i.e. 150 seconds at 24tph for HSR and Caltrain combined. Platform dwell times of at least 16 minutes are possible even at this insanely high level of traffic, which SF will almost certainly not attract in the next 50 years - if ever.

The downside is that the Mission Creek outfall needs to be crossed at grade, so a short section of 7th Street would lose two traffic lanes. More significantly, Townsend Street would be permanently severed at 7th unless an overpass were constructed.

Throat And Platform Layout

The second thing you'll notice is that the approach to the station is both long and straight, ideal conditions for designing a throat for minimal interference. In this case, the inbound and outbound tracks need to split into two levels that I call -2 and -3 for reasons that will be come obvious shortly. This split begins immediately east of the curved section. By the time the tracks reach Jessie St West, they need to be stacked 2x2 on top of each other. This ensures that any inbound trains waiting to reach a platform can wait west of 3rd Street on the correct level, without blocking inbound trains on the other level.

Near 3rd Street, the two tracks on each level first combine into a single track and then immediately split via a three-way point into a through track and sidings left and right of it. These sidings are the west platform tracks (2-1, 2-2 & 3-1, 3-2), each with its side platform. A second three-way point near Shaw Alley reconnects these sidings to the through track. East of this point, the through track may descend for a block to compensate for changes in the surface level (at-grade does not mean constant elevation above MSL). Regardless of length, trains always stop on the west platforms such that one end is at Shaw Alley.

A third three-way point at 1st Street provides access to two additional platform tracks east of that location (2-3, 2-4 & 3-3, 3-4). Regardless of length, trains always stop on the east platforms such that one end is at 1st Street. Space should be reserved for a future fourth three-way point reconnecting the east sidings to the through track, for reasons that will become obvious shortly.

Since there is no room for an access platform, the through track between these east sidings can only be used for train storage. Perhaps it could also be used as a tail track for the western platforms if cleaning/provisioning staff board and alight there. However, the only emergency escape route would be at Spear Street, which implies walking the length of the train first.

The layout described above means trains don't block each others' movements any more than necessary. The longest wait states would occur for an inbound train waiting for another to clear one of the east platforms, since that needs to travel up to half a mile first. At an average speed of 20mph along the center track, that would take 90 seconds. The worst-case wait state for a western platform would about a minute. In practice, well-planned operations would minimize wait states or eliminate them altogether by slowing inbound trains down rather than forcing them to come to a full stop. Worst case, there is room for one full-length train between Jessie Street West and 3rd Street.

Operationally, any given train would always stop such that one end ends up at 1st Street, within half a block of the Transbay Terminal building. In addition to supporting regional buses, the building would also contain the customer service counters for train operators, baggage depot, police station, shops, cafes, lounges/waiting areas, bicycle parking etc. Taxi and city bus stops are located on the plaza between Minna and Mission, Fremont and 1st. In other words, the concept of a multimodal hub is preserved even though the tracks are not underneath the building.

The train station would be really a bare bones affair: just the trains and access infrastructure plus some ticket vending machines and restrooms at intersections with cross streets. Mission Street isn't wide enough to accommodate any other facilities on the platform levels.

Concourse Level

Strictly speaking, there is no need for a formal concourse level at -1. Since the design uses side platforms throughput, surface streets could be used to access all of them. However, given the anticipated number of passengers, it is safer to provide pedestrian underpasses across Mission Street, even though that means digging a deeper (i.e. more expensive) trench than would otherwise be necessary. Moreover, the desire to provide four full length platforms per level means long walks are inevitable for some passengers on full-length trains. The concourse level would therefore feature moving walkways in both directions along its entire length, interrupted at the eight locations at which there are exits to the surface on both sides of Mission Street.

To either side of these central moving walkways would be regular ones, about 10 feet wide each. To either side of those would be the baggage screening areas, if Homeland Security requires any. Airport-style check-in is possible but usually (a) conductor(s) on board the train will inspect passengers' tickets. Note that security procedures are pointless unless they are implemented at all HSR stations. In any case, terrorists haven't attacked a long-distance train in Europe since Carlos the Jackal did in 1983. Instead, they've targeted subways and commuter trains as well as high speed tracks. Train stations are also at risk.

Optionally, staff could prevent passengers waiting to board from descending until they get a signal from colleagues below that all arriving passengers have cleared the platform. Unless the fire marshal requires this at all times, it would normally only be done during peak periods to avoid excessive congestion on the platforms. Note that the platforms on the two train levels would feature multiple stairs/escalators to the concourse level. Escalators intended for the disabled, women with baby strollers etc. would connect all three levels. Connections directly to the surface are ok only if Homeland Security decides it doesn't need to enforce access control to the platforms.

Pedestrian Cross Passages

A pedestrian passage underneath 1St Street between the train station and the Transbay Terminal building would not be absolutely essential but nevertheless very useful, given the vehicle traffic on the surface. Such a passage is currently planned as an optional extra between the building and Market Street, but under Fremont Street. Note that in the station design discussed in this post, the building would not need a concourse level for transportation purposes, just stairs/escalators/elevators to the pedestrian passage, if any. Moving walkways along this 200 foot stretch would be convenient for passengers and increase throughput capacity.

Additional pedestrian passages under Main and 2nd Street could connect the train station and indirectly, the Transbay Terminal building to both Embarcadero and Montgomery Street BART/SF Muni. Again, not strictly necessary but useful.

Note that all these underground pedestrian passages would provide shelter against the elements. Unfortunately, they may also attract pickpockets, buskers, alcoholics, drug addicts, graffiti artists, homeless people and others just hanging out for no apparent reason. Bright lighting, ventilation, cleaning and security patrols are needed to ensure passengers will feel safe and comfortable enough to use these facilities. It may make sense to ensure the passages are private rather than public property so security has a legal basis (trespassing) for evicting disruptive individuals.

Phasing And Extension to East Bay

What I've described above is actually the fully built out terminus station. If desired, construction could be divided into two phases to accommodate budget constraints. Phase One would be the access tunnel via 7th an Mission plus the four west platforms, possibly the pedestrian cross passages to the the Transbay Terminal building and Montgomery Street BART as well. Phase Two would be the east platforms beyond 1St Street plus the pedestrian passage to Embarcadero BART. The west platforms could already be in operation at that point.

If and when a decision is made to build a second transbay tube, the Mission Street station design affords a fairly straightforward if expensive connection via Point Alameda and into downtown Oakland up Franklin. On the SF side, the tracks should already be deep enough to avoid conflicts with the descending SF Muni subway tracks under the Embarcadero. There is enough room for the through track at level -2 to descend to level -3 between Spear Street and the water's edge. However, unlike the west throat, there is no need to double-track this new one on the east end: instead, the four platforms on the upper level would be used for inbound and the ones on the lower level for outbound trains (or vice versa). This operations change turns all eight platform tracks into run-through types, thanks to the four three-way points installed on each level.

In addition, the presence of a through track in each direction would permit trains to bypass all of the platform tracks. That could be useful for e.g. high speed cargo trains if a transshipment terminal were built in the East Bay or, for trains supporting a major sports or other event on Point Alameda or in Oakland. Normally, however, trains would dwell for a considerable amount of time in SF. Even at 24tph for HSR and Caltrain locals combined, having four platforms each way available means dwell times of close to 20 minutes would be feasible.


I've already touched on a number of caveats, such as the consequences for 7th and Townsend Streets and, the need to pass under SF Muni tracks at the Embarcadero. In addition to those, there is a potential conflict with the planned SF Muni Central Subway. That is supposed to dive under the BART tracks at level -3 and, it looks like the chosen alignment (alternative 3B, Fig 2.12 would be deep enough at Mission Street to avoid a conflict with the alternate heavy rail access tunnel described above. However, if heavy rail station under Mission Street is considered, the clearance issue at 4th Street ought to be double-checked before ground is broken on the Central Subway. I don't have a good sense of how the surface grade changes between 4th and Embarcadero along Mission Street. The heavy rail tunnels should be level from 3rd to Shaw Alley and from 1st to Spear Street yet still deep enough to permit a concourse level plus a future extension to Oakland.

Another caveat is that passengers need to know not just the platform but also the car number of their train to descend at the appropriate point. The preferred approach is mandatory seat reservations (cp. TGV in France), the receipt can then include this information. Given the width constraints, pedestrian traffic along the platforms should be minimized. Reservations also ensure there are no standees on the train and that no-one needs to walk far inside the train to reach their seat.

Also on the receipt could be helpful hints, e.g. the nearest BART/SF Muni subway/SF Muni streetcar. Indeed, a good reservation system would ask about your connecting transportation to offer you a seat that minimizes your transfer distance. That could be printed on the receipt, along with an indication of how many minutes to budget for an comfortable transfer incl. security screening, if any. The flip side of seat reservations is that a late change to the platform, especially from one west of 1st Street to one east of it (or vice versa), would cause significant inconvenience for passengers.

Finally, I've assumed throughout that all eight platforms in the design would be created equal, i.e. that all would feature level boarding at the international standard of 3'6" (1067mm). Caltrain is hamstrung by a ridiculous 1948 rule intended to protect freight railroad workers hanging off the sides of cars. Is it really appropriate to perpetuate ye olde tyme practices to the detriment of passenger convenience and throughput capacity, in a station that no freight train will ever enter? IMHO, if Caltrain wants access to any downtown station in SF, it needs to buy EMU equipment that can cope with both level boarding and the lower level (2'1" = 639mm) that the platforms at its other stations are built to. If UPRR and CPUC have no objection, those could be upgraded to level boarding as well over time.

Heads Up: Neighborhood meeting on HSR for residents of the Willow Glen neighborhood in San Jose, on Wednesday, April 8 at 1292 Minnesota Ave from 7-9pm.

The purpose of the project-level EIR/EIS phase is to nail down how the HSR alignment should be constructed in each location, after close consultation with the affected communities. The starting point will be what CHSRA consultants suggested for the purposes of cost estimation prior to the election. This information has been available online since 2007, though you do have to look for it. The Authority is a planning body, i.e. a bureaucratic organization - most of its documents were designed for hardcopy rather than the web.

The objective of the HSR project is to deliver a net gain for the state California, especially for the cities served by stations. The following resources may help you understand what CHSRA has done to date regarding San Jose and the Willow Glen area in particular.

If you plan to attend this meeting, you may want to download selected resource documents at home and bring them along on a laptop.


Anonymous said...

What's the big del about using the japanese train. I'd rather use the french trains anyway.

Anonymous said...

I think all these change and re routing through san francisco ( trying to run it up 7th will open a huge can of worms politically as that neighborhood has special protections) and re designing the terminal now, well it's just to much. the tbt has already been designed and is on its way to construction. I think hsr is going to have to make do.

Rafael said...

@ jim -

have you ridden both French and Japanese high speed trains? How about German, Italian, Spanish, Chinese or Korean ones? How about a Canadian design?

It shouldn't be up to you, me or some real estate developer in SF to make that decision now, long before a proper vendor evaluation process can even begin. Japan is the country with the most experience in constructing and operating integrated systems of lines, trains and people in active earthquake country.

Besides, the large curve radius also helps cut down noise and improve throughput.

Wrt the redesign of the Transbay Terminal: don't build a full concourse level nor the trainbox. That's basically it.

Wrt that huge can of worms on 7th Street: what do you think the very public dispute between TJPA and CHSRA is? Could it be that a certain someone is turning NIMBY on us?

Alon Levy said...

What's the point of merging the two tracks on each level of the station? You're just creating a bottleneck: an outbound train on track 2-2 may conflict with an inbound one on track 2-1. It shouldn't be any harder or more expensive to instead have the two tracks split to three, without first combining into one track.

I'm also skeptical of the idea of having two platforms one after the other. Has it ever been tried in any rail system? If not, it might be safer to tunnel under Howard instead, and use the current design for the TBT.

Rafael said...

@ Alon Levy -

the inbound and the outbound tracks on each level merge because east of that point, you essentially have a single track alignment with four sidings. Sooner or later every terminus station ends in single tracks. In this case, the width of the street constrains the number of tracks that can be laid down in addition to side platforms.

What you're suggesting is a pair of overlapping three-way points. I've never seen such a beast nor would it do anything for throughput, since HSR trains are up to 400m (1320 feet) long. The critical issue is getting trains off the single track and onto the dual track as quickly as possible. That's why the east platforms are more of an issue here than the ones west of 1St Street.

I haven't ever seen this implemented before, but then most cities (and countries) around the world never allowed their railroad infrastructure to wither on the vine for half a century. I agree that more detailed analysis would be useful, but I don't have access to a simulation tool for train operations.

The reason I'm fairly confident of my back-of-the-napkin calculations is that Mission Street provides a long, dead straight approach to the platforms. That means trains can utilize their acceleration potential to vacate platforms "bat out of hell" style.

Running two tracks down Howard with a crossover X and a couple of three-way points to splay them out into six platform tracks would be possible, but the Transbay Terminal does not line up well with that Street. Trains could not clear the throat any faster because the curves would constrain their acceleration. Besides, the Central Subway's Moscone Station will occupy the space under 4th and Howard.

The one advantage of putting tracks underneath the TT building is that you have two choices for any future transbay tube: Howard or Main. On the other hand, six platforms is fewer than eight.

plem said...

Another caveat (maybe): Full platform length has to be 450m instead of 400m (some regulation), since 16-car trains have a length of >=400m. With all those threeway points, that will extend the underground trainbox to 4th street and make it almost a mile long. Feasible?

A [stupid] question.
Instead of

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why not this ?

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BruceMcF said...

jim said... "the tbt has already been designed and is on its way to construction. I think hsr is going to have to make do."

But the original plan, before the stimulus money was passed, was to build the TBT now, and then build the train-box later.

Since it is quite possible that the TBT design does not meet Prop 1A requirements to qualify to be part of the HSR system, its legitimacy in requesting HSR funding is certainly open to attack. And with more than $8b in funding requests certain to be going in to get the $8b, that's taking a big risk on what ought to be a slam dunk.

Richard's design seems to fit within the footprint of the current train box, and in narrowing the main tunnel from three tracks to two, would cut down on the cost of the DXT, which is as of yet unfunded.

Rafael: "Safe operations of sections of a line with moderate speed limits are possible with as little as 2.5-3 minute headways, so 5 is actually conservative."

The HSR network has to permit consecutive HSR services at five minute intervals. That means 2.5 minute headways if Caltrain services are mixed in and they still want the DXT and the TBT train-box to qualify as part of the HSR network.

yeson1a said...

The link to the SFgate tells the whole story about this tiff..Its classic A Team VS B team San Franciso pols. I would not worry HRS is going to the TBT ,issues or not.Everyone with any say in anything here wants it SO. Kopp is out of luck here.I think it wont work as well as the backers claim. Im hoping for the rest of the project its not a huge money pit drag. As far as this Mission station idea its not on anyones radar here. in fact the Central Subway will be in its place and that is a big want item with the pols here. HSR may at first use 4th and King but it is going to 1st and Mission ..Hell or high water in the mind of the powers here

BruceMcF said...

Also, Rafeal: "Still, with a minimum curve radius of just 150m (~500ft), even Richard's improved version would effectively preclude the purchase of proven, off-the-shelf Japanese high speed trains - those need at least 280m, preferably more."

Richard's minimum curve radius is 190m (623ft). I don't think that given the EIS he can get it any looser than that in the train mouth and still have 400m platforms ... I get the impression he would push the whole thing to 250m minimum (820ft) if he could ... that would be outside the minimum turn radius of even the Japanese trains in use on the Taiwanese system.

ian said...

I like this design. it makes more sense: it is cheaper to build, it has higher capacity, is expandable, and can be built in phases. someone get kopp and newsom on the phone, they need to see what citizen-engineers can think up. I seriously hope someone at CAHSRA reads this entry.

Caelestor said...

This plan is much better, simply because there's only one turn.

Adrirondacker said...

How many stops on the shuttle bus that gets you from the far western end of the platforms to Beale Street?

BruceMcF said...

Shuttle buses ... San Francisco don't need know shuttle buses ... just a nice little Monorail ... a genuine, bona fide electric six car monorail will cover the distance required.

Seriously, there's no EIS for a Mission Street station, so the path ahead to it is to sabotage the funding of the TBT train box out of the stimulus money and get into the city political fight for years and scrap and claw to get the option studied, and then to get the EIR/EIS work funded, and even then its a lot of trouble to add two platforms, when if you've got the Jones to add two platforms, the TBT train box could be made 1/3 deeper and the Caltrain platforms brought up to the Mezzanine.

OTOH, in Europe, busy stub terminals see services scheduled to depart six minutes after arrival, since the services do not do their terminus operations at busy stub terminals. Given the expense of underground platforms, no matter what the design, there's an argument that can be advanced that the system should economize on their use (and, indeed, was advanced quite vigorously at the Caltrain HSR compatibility blog in response to my two eight platform track TBT proposals).

Adirondacker said...

Shuttle buses ... San Francisco don't need no shuttle buses ... just a nice little Monorail

Bruce, I missed this on the first go round. The western platforms are served by the Montgomery St. Bart station. ( I assume it would work as well for the Muni riders there ) The eastern platforms are served by the Embarcadero BART. . . they could take BART or Muni from one end to another. No need for shuttle buses or monorails.
And since there are subway style entrances dotting Mission, if you are at the far western end the entrances at Mission and 4th might make Powell a better choice, especially if you are headed west.

... I was rereading it because I was searching for the punchline. I was sure I missed it.

BruceMcF said...

@ Adirondacker: oh, good catch, they can take the BART from platform to platform. How much is BART for a one-station ride like that?

Adirondacker: "I was rereading it because I was searching for the punchline. I was sure I missed it."

OK, so the politician says, "There are billions of dollars available from the Federal Government and HSR projects that have their EIR/EIS work done are likely to be in the front of the line", and then there's this blogger ...

... stop me if you heard this before ...

... who says, "never mind applying for the money, I got a new layout that will solve everything".

C'mon, that IS the punchline.

Well, no, I'm not busting a gut, but down at City Hall they are falling over themselves, they are laughing so hard they can hardly catch their breath.

Seriously, $8b in Federal money with no state match, the politicians are going to be like moths to a flame.

The only reason that the CHSRA has any leverage is that Prop1A puts requirements on the HSR network, and the TBT train box seems to be so badly designed that it might be a bureaucrats judgment call whether it can be "reasonably" expected to be an investment toward developing an HSR system ... and of course, bureaucrats only have real power when they say "no" to someone on the way to saying "yes" to someone else.

But a layout that will take two or more years to get through the EIR/EIS process when the applications are going to be due in ASAP ... that's in an alternate universe where the $8b in HSR funding was not passed, and where the TBT is going ahead in Phase 1 without the train-box because there is no way to fund it.

Eric said...

Although your intentions are good, I think your platform designs are too long. I travel to Europe frequently and ride the HSR lines in France. At their stations such as Gare De Lyon, it is a pretty good walk when you are riding in first class, because that is always at the front of the train. 16 (Okay, more like 6-10 when you take out the power units)car lengths is longer than you think when in a hurry or have luggage.

Remember, Americans are more lazy and do not like walking very far. If it is too much work for them the first time, they will not be returning customers. Keep it compact and everythin close. Not a two mile long station.

Just my opinion.

Brandon in California said...

Frag... that's a long post. I quit halfway through!

I feel the two agencies should have been working more closely together on this; however, I also feel the CHSRA is the lead agency on this project on all matters.

flowmotion said...

One thing not mentioned ... the second transbay tube is also intended to support BART, connecting to a subway down Mission Street.

I suppose you could have a two-level station as on Market St, but it would complicate the concourse level. And it's just another agency HSR would have to fight with.

Anonymous said...

Brilliant! I love it. Solves a lot of problems with the TBT route, plus leaves the system open for future extension.

The downside is that the political personalities dictate the reality by drawing the lines on the map; engineers have to deal with that. And right now the political goliaths are arguing over "To TBT" or "Not to TBT". This route, while entirely sensible, would very likely be used as F.U.D. to weaken the "To TBT" side, with no intention of following through with this 7th-to-Mission-to-TBT alignment.

AND, and this is a huge "and", the same political players have a serious stiffy for the 3rd Street MUNI tunnel. As stupid and expensive and unworthy as that project is...

Andy Chow said...

I don't think it is reasonable to throw away a project because it would preclude some vendors from bidding with their existing designs.

Think about it from a cost-benefit perspective, the benefits from the TBT site is significant enough to warrent changes in train operation to increase throughput from a 40 minute layover suggested by HSRA, even if that means hiring extra personnel.

Also, it is fair for Caltrain and most HSR riders if TBT were cancelled because TBT couldn't handle a few more trains that HSRA couldn't justify operating? By the time the Bay Area has enough population to support 12 trains an hour, we might as well have an Oakland station or another station in SF to divert traffic. Meanwhile, some trains could turn back in SJ.

yesonHSR said...

There never will BE any Mission station PEROID .its just some HSR dream on this board. No plans what so ever have been proposed..nor will they.Downtown real estate interest has voted 1st and Mission .The only reason its not there on opening day is MONEY

Adirondacker said...

How much is BART for a one-station ride like that?

Last time I rode BART and Muni the same price for either. So not only do they have BART as option they could take the MUNI lines running under Market or the streetcars or the buses. Maybe your HSR ticket will be proof of payment for Muni in those few blocks, so no fare.

His pedestrian underpasses to the "BART" station don't go to BART, they go to the concourse above Muni and BART. So if you want to do this you'd probably be on Muni anyway. . . at least I assume the pedestrian underpasses connect to the concourse. I imagine connecting them directly to BART would need fare controlled areas and non fare controlled areas with all sorts of escalators and such. Connecting it at the concourse which is just below street level would make most sense. . . anyway the tracks for BART are against the wall. Passengers darting across the tracks to get to the platforms wouldn't work out very well.

HSR projects that have their EIR/EIS work done

Other than to surf over maps of ROW that Clem over at the Caltrain HSR Comparability has I haven't looked at the EIS in detail. ( At least I think those maps come from the EIS or similar documents.)

..... is the EIS still valid? Does it account for wedging Caltrain and HSR into Transbay or is it for Caltrain only? After all double decking passengers on the platform is something an EIS should look at.

And no one is talking about where you put the 20 trains an hour that are coming in from Caltrain East.

I suppose they could continue the concept east of the Embarcadero but then we are back to a monorail from the platform to the place where you can get to the street.. because the far eastern end of the platforms is half a mile from shore.

Can't build a BART station out there because BART is at capacity. BART being at capacity is why I come up with "Caltrain East". But everyone is busy trying wedge 10 pounds of transportation into the 5 pound site of the Transbay Terminal - the stuff from the south. They haven't thought about what you do with the other ten pounds that will one day be coming in from the east and north.

Andrew Bogan said...

@Andy Chow

I don't think it is reasonable to throw away a project because it would preclude some vendors from bidding with their existing designs.

It is not just "some vendors" that we are talking about. It is the only vendors with a proven record of designing HSR trains with adequate earthquake safety features. My understanding is that the reason Taiwan switched from European rolling stock to Japanese shinkansen train sets at great cost in the middle of their design of the system was a realization that earthquake safety was critical and Japan's shinkansen had a proven record (no deaths when the Joetsu shinkansen derailed in a major earthquake near Niigata). Seismic monitoring and safety systems are not a minor issue in California. It would be absurd to rule out Japanese trains in advance due to bad station engineering.

Anonymous said...

@ rafael. I haven't ridden any of the trains actually any where in the world. I just like french stuff and I don't like asian stuff ( ok i like thai food...) as for 7th street. I wold love to have it run up 7th and terminate in the basement of the new building I will be living in at 8th and market ( see trinity plaza project) because I may very well end up working there and wouldn't that be a nice commute. BUT, I'm pretty sure that 7th is in the western soma plan and - a little chunk of residential that has been designated to not be bothered and to maintain its divers and affordable housing element blah blah blah, something the BOS did. So im just saing its bad enough with tjpa and cahsr but if you stir up the sf BOS too, the thing will never get built.

Anonymous said...

besides ill bet the japanese train have smaller and more crowded seating arrangements too. we needs seating for americans and their big backsides.

Anonymous said...

the mission plan would have to go under msoscone which it two stories deep under mission, that could be done. but then it would have to also go under he central subway - which, at mission has be deep enough to gp under bart at powell ( putting it four stories 4th - to station depth at 2nd. could be done im guessing with those tunnel machines. but that is a lot of rigamarole to go through. when all they really need to do is finish that stupid tail track and loop it back to forth.

Anonymous said...

Personally I detest all growth and development in SF because they keep shoving more and more people in here and I don't want them here as it is destroying our city. This project will no doubt have a very negative effect.... BUT, since I do know that it is important for california, unlike the peninsula folks, I'm not against it, and I'll have to put up with the collateral damage for the greater good. I just hope Im dead by the time that thing brings a zillion more units of BS high end housing for snot nosed yuppies and hipsters into town. likely there will be some lag time on that.

Andy Chow said...

Earthquake, etc is another red herring. Are you saying that Europeans trains are less safe? and that California has to build a Japanese replica to obtain the level of safety?

Japanese vendors can always bid knowing that we need to get to downtown and that they do have to ability to design around that critical access need. That's their job, not our job by abandoning downtown access in hopes they might win the bid with their old design.

Anonymous said...

oh hey, did anyone think of maybe making the existing planned train box longer by curving the whole thing with an acceptable radius... I mean it doesn't have to be straight does it ( this is sf after all) by stretching out the approaches and exits and curving the platforms can you get room for two trains - one behind the other per platform?

Anonymous said...

Another solution might be to add a pair of simple narrow remote platforms on the tail tracks so that two train at a time could be loading and unloading, train 101 pulls up 5 mins later 102 pulls in behind it then 102 becomes 203 and pulls out and 101 becomes 204 and pulls out five minutes after. access the remote platform by simple moving sidewalk corridor. In fact make the space and don't operate the second set of tail track platforms until 90 years from now when they will actually be needed.

Anonymous said...

Just for the record, a typical European HSR train is very narrow at 2.95m width, while Japanese trains are at 3.38m width, barring the mini-shinkansen trains on upgraded old lines. Japanese trains are actually longer and larger than European ones, and can fit more people in one train.

Anonymous said...

On the right of way between San Jose and Gilroy, didn't UP agree to give VTA the option to purchase half of ROW if VTA chose to? Or is this dead?

BruceMcF said...

jim said...
"oh hey, did anyone think of maybe making the existing planned train box longer by curving the whole thing with an acceptable radius... I mean it doesn't have to be straight does it ( this is sf after all)"

Yes, this is how Richard's design gets the curve radius up to 190m (630ft), by curving the back 200m of the platforms so they all fit into the space originally allocated for the tail track access. He uses a curve radius of 1000m, which eliminates the problem with wide gaps that would be a problem with the original TJPA design.

"by stretching out the approaches and exits and curving the platforms can you get room for two trains - one behind the other per platform?"

He gets in effect somewhere like another 50m to 100m, used to shift the head of the platform back and allow a looser curve in the approach to the platform ... there's not an extra 400m available from curving the platforms.

He also includes mid-platform crossover switches, for maximum flexibility when dealing with sets that can fit on a half platform. In particular, if there is a mix of short and long HSR sets and short and long Caltrain sets, putting a short HSR at the back of the T-23 platform would allow the Caltrain T-22 platform to be used as two independent short train platforms (cf. TJPA layout (jpg), Richard's train box (jpg)).

BruceMcF said...

Jim ... "..... is the EIS still valid? Does it account for wedging Caltrain and HSR into Transbay or is it for Caltrain only? After all double decking passengers on the platform is something an EIS should look at."

For the EIS, if it fits inside the project footprint given for the EIS, with only the surface buildings marked as affected on the original EIS affected, and the modification falls within the "not a final design" caveat, they are good to go.

The self-loading freight are not part of the scope of the EIR/EIS.

"But everyone is busy trying wedge 10 pounds of transportation into the 5 pound site of the Transbay Terminal - the stuff from the south. They haven't thought about what you do with the other ten pounds that will one day be coming in from the east and north."

Some of the bottleneck is because its a terminal ... if the innermost island becomes a through platform, the crossover in getting back out of the extreme outside Caltrain platform track goes away, because the trains keep going through to the east instead. For maximum capacity, you'd want to dig a dive for the platform track that becomes the through "southbound" track. And in any event, that'd be through a more flexible part of Richard's station throat layout.

Even if the back of that through platform in Richard's design would have to be clipped by 50m or 100m to allow for the dive to the eastbound tunnel, that would still be long enough for twelve car EMU's ... the advantage of being able to place two six car EMU's on that platform go away when its a through platform.

An advantage of a design with more operational flexibility is that there are likely to be fewer modifications needed if there is a major modification to a part of the system.

Rafael said...

@ Plem -

yeah, a possible variation. However, I'm not aware of any requirement to support trains longer than 1320 foot (400m) in California.

@ adirondacker, Eric -

there are city buses on Mission, but the concourse level of any Mission Street station would also feature moving walkways, as would the pedestrian cross passages.

So if for some reason you entered the station at 3rd Street but your train is on platform 2-3, you could use those walkways to make your way to 1St Street (or beyond that if your seat reservation instructed you to do so).

Alternatively, a savvy traveler who knows he will enter at 3rd Street would purchase a ticket for an earlier or later train that is scheduled to depart from platform 1 or 2 on either level.

@ Brandon in San Diego -

slacker ;^)

@ flowmotion -

so cancel the plans for a second BART tube in favor of one for standard gauge. Electrified Caltrain from Oakland via Point Alameda - why not?

Sooner or later, any standard gauge tunnel to Oakland would also be connected to the line served by Amtrak CC. There's a bunch of UPRR, FRA and dual mode (either diesel or 25kV AC overhead electric) locomotive/multiple unit issues to resolve first.

@ anon @ 9:41am, Jim -

as mentioned in the post, the final alignment for the Central Subway is under 4th Street, with the SF Muni tracks diving under BART at Market. They're already pretty deep at 4th & Howard (Moscone Station) and look deep enough to support my cunning plan even at Mission.

But yes, someone would need to double-check that, especially in light of the surface gradient between 4th and Embarcadero. Platform tracks should be level.

Andrew said...


"besides ill bet the japanese train have smaller and more crowded seating arrangements too. we needs seating for americans and their big backsides."

Hey, guess what, I've ridden the shinkansen and it's a very spacious and comfortable train.

You say a lot of things out of ignorance, that's a pretty annoying habit.

Andrew Bogan said...


besides ill bet the japanese train have smaller and more crowded seating arrangements too. we needs seating for americans and their big backsides.

For clarity, the other "Andrew" above is not me.

I have ridden in both Japanese shinkansen trains and the French-built Alstom trains on the KTX in Korea. Both are reasonably comfortable and the French train is a bit faster, but the car width and seating space is actually larger on the Japanese trains.

Anonymous said...

I'm jsut partial to the french. I like there style and way of doing things. Asia, not so interested so my personal preference is tgv. Since all any of are doing on this blog is sort of daydreaming and "what if" unless any one here is actually on the hsr board. of course end the end we will all take whatever they give us right. be it transbay or fourth and king, redwood city or palo alto, pacheco or altamont. japanese or french.. Id rather have the train for from 8th and market to palm canyon drive. So any thoughts on the parking situation for transbay terminal?

Andrew Bogan said...

@Andy Chow

Earthquake, etc is another red herring. Are you saying that Europeans trains are less safe? and that California has to build a Japanese replica to obtain the level of safety?

Earthquake safety is definitely not a red herring. It is critically important that it be properly addressed or Californians simply won't ride this train. Clearly if the Japanese have already designed a functioning seismic monitoring and safety system, then other vendors could design one, too. However, it would be pretty foolish to approach the vendor selection process with an attitude of "we need a unique train designed for California since our engineers are too stupid to keep all our options open".

Cost will be critical for every part of this expensive project. Making arbitrary decisions that affect vendor options in the design is foolish. California's goal should be to buy "off the shelf" train sets, not force vendors to customize something to our needs--that is what we did with Acela. Oops.

Here's a NY Times article on Acela, dubbed "le cochon" (the pig) by its designers at Bombardier and Alstom in Canada.

crzwdjk said...

Fun fact about THSR: even though the trains are Japanese, the track, which is the important thing for earthquake safety, is European. So much for that. Oh, and even if we import trains from Japan, they won't be the same size, as they'd still have to fit into the US loading gauge, because unlike Japan, we don't have to build a standard-gauge network completely from scratch.

Andy Chow said...

The TBT design may not fit every HSR vendor, but the design is still compatible with a HSR system. The design does not require brand new inventions.

Acela's FRA compliance requirement is too high. TBT's requirement is not anywhere close. There might be other parts of the line that put as much if not more constraints.

Japan is capable to make quality products for other countries that they don't use at home. Japan is right hand drive but makes left hand drive cars for the US. Japan makes TVs and electric appliances that don't work in Japan. Japan also makes the Caltrain gallery cars that they don't use at home.

David S said...

I have to agree a mission st. station is a fantasy. I'd also have pretty big concerns about a station that long. Lots of airports are laid out like that and its just a pain.

As to fat americans on shinkansens, the HSR I rode in Japan was far more generous than any domestic airplane I've ever been on. If you're comparing HSR to a Hummer with bucket seats, HSR will never win. If you compare it to the alternatives, eg, a 737 configured for short hauls, HSR is going to win. Anyways, a single station that hasn't even been BUILT YET should not dictate the trains we have to use, *if for no reason other than cost*. If a French vendor realizes they are -literally- our only option, we won't get a competitive bid.

Ultimately it seems to me the TBT can support the trains needed, as long as the length issues is fixed. Realistically, but the time the system needs to support more riders, there will be a central subway and a ton of high rise development around 4th and king. A significant portion of riders may choose to terminate there instead out of convenience.

Kopp, Newsom, etc, etc all need to sit down and get their heads out of their asses. All projects like this have conflicting goals. If they aren't working this out in a constructive manner, they need to. If they are working it out, they need to tell the public that--I am tired of hearing "lol this project is a pork disaster run by idiots with the HSR equivalent of penis envy" from deniers due to politics.

Andrew Bogan said...


Fun fact about THSR: even though the trains are Japanese, the track, which is the important thing for earthquake safety, is European. So much for that.

Not sure what one even means by a "European track". Yes, they chose a European signal system for THSR, but the seismic mitigation techniques used in the track construction are simply international best practices for seismic engineering, nothing European about it.

The seismic monitoring system along the track is laid out almost identically to the one developed in Japan and it interacts directly with the train sets, either warning the train driver or automatically depowering the train, depending on the severity of the measured seismic disturbance by the track's sensors. All of these systems depend on the quake being typical (that is having separation between the initial p wave and the destructive s wave), which is not always the case and why the Joetsu shinkansen derailment occurred in October 2004 (luckily without injury).

Presentation on Seismic Safety from THSR

Article on Joetsu Shinkansen earthquake derailment.

BruceMcF said...

jim ... "BART being at capacity is why I come up with "Caltrain East". But everyone is busy trying wedge 10 pounds of transportation into the 5 pound site of the Transbay Terminal - the stuff from the south. They haven't thought about what you do with the other ten pounds that will one day be coming in from the east and north."

... though for an eastern standard grade tunnel, a truncated version of the Mission Street plan might be viable ... at least with Richard's version of the DTX that is two track before the fan-out. Branch there to the outside then dive, and a deep through train box underneath mission could connect up to a BART/TBT people mover. Then instead of placing pressure on the TBT train box, it relieves pressure, with through expresses running to Mission Street and terminal locals running to the TBT.

If a bypass track is a relief valve rather than receiving high use, two "head to head" platforms ... three tracks through with a side platform on one side, then shifting for the side platform on the other side ... would be workable. The platforms could be wide enough for reasonable access and egress during peak, and not being forced to make the platforms long enough for the longest of the HSR's combined with the natural horizontal movement of subway escalators would make the "platforms stretching out in opposite directions" system much less of an issue.

Its the idea that a new layout without an EIR/EIS that would needs a new EIR/EIS can enter into the current controversy that falls over ... in terms of a supplementary train box, any supplementary train box will need a new EIR/EIS, and is located ten to twenty to thirty years in the future, so Mission Street could well be an option.

Anonymous said...

@david "Kopp, Newsom, etc, etc all need to sit down and get their heads out of their asses. All projects like this have conflicting goals. If they aren't working this out in a constructive manner, they need to. If they are working it out, they need to tell the public that--I am tired of hearing "lol this project is a pork disaster run by idiots with the HSR equivalent of penis envy" from deniers due to politics"

THAT is the the truth in a nutshell. Why forinstance is SF putting in a new subway that misses the transbay termnal by two blocks? There will be no muni rail connection to the tbt.

Clem said...

they chose a European signal system for THSR

Did they? Last time I drove one (heh heh) it was fitted with Hitachi's Digital ATC system. Weird.

Herbie Markwort said...

Something I have yet to see adequately explained: aside from the 1999 SF Prop H, why must HSR go to the TBT? Is 4th & King really so far removed from the financial center that siting the HSR station there will significantly reduce ridership? Is 4th & King simply a bad place to put a HSR station? By all means, do everything possible to get Caltrain and the daily commuters that ride it into the heart of SF and to their jobs, but it seems unnecessary for HSR to do the same.

Adirondacker said...

Herbie, there's a big bus terminal being built over the train station ( Or a train station being built under the bus terminal depending on the way you want to look at it.) It's an easy walk from BART and Muni and an escalator ride from all the buses that serve the East Bay, Marin, Sonoma, Napa. At 4th all those buses and trains are a mile and half away.

BruceMcF said...

Herbie, what Adirondacker said. It is a local urban station that is placed based primarily on the destination or origin passengers within walking distance ... the recruiting area for a given HSR station is much larger, and so a central urban station should be placed for the best intermodal connections available.

Arguably they should have placed the main SF intermodal center where it was convenient to bring together trains of all sorts and then plopped a bus terminal on top, but since they went ahead and did it backwards, that's got to be worked with.

Luckily SF voters made it a local proposition that the TBT be the HSR station, so the TJPA has statutory obligations to fulfill ... its not a case of the CHSRA coming cap in hand begging for a place at the station.

Anonymous said...

There are 100,000 jobs within 1/2 mile of 4th/King. There are 300,000 jobs with 1/2 miles of TBT.

Andrew Bogan said...


Looks like you are correct at least with respect to the ATC system being Japanese for THSR.

My confusion was supported by Wikipedia's mention of:

Some of the same Japanese companies won another project in December 2005 to build a high speed rail link to Taiwan Taoyuan International Airport, with the exception of the signaling system which has been awarded to Westinghouse Rail Systems.

. . . but that is for the HSR extension to the airport, not the existing line. My mistake. Looks like less European technology went into the final design than I had thought.

Herbie Markwort said...

I understand the backwards bus terminal deciding the location of the HSR station logical leap. I understand that the TBT is closer to much more jobs than 4th & King. I guess I just don't understand what makes a 1-stop Caltrain ride to 4th & King so much different than a 1-stop BART ride to West Oakland. It wasn't long ago that this blog was discussing a HSR station at Lindbergh Field 1.5 miles from downtown San Diego. I assume it's the captured bus audience at the TBT that's the clincher.

lyqwyd said...

This may have been discussed before, but why don't thy just route the line on Embarcadero, and then up Main St (where the tail tracks were intended to go)?

The curvature would be much better, plus there are fewer business along Embarcadero to complain about construction. It also seems like it should be easier and cheaper, you can do cut and cover the entire way.

flowmotion said...


"so cancel the plans for a second BART tube in favor of one for standard gauge. Electrified Caltrain from Oakland via Point Alameda - why not?"

Other than the fact there is zero political and funding support for that idea, is there really the need for 4 standard gauge tracks under the bay? And what do you do then about the BART capacity problem? Build an entirely separate track system?

Frankly Rafael this sort of statement belies the idea that you are proposing pragmatic solutions to HSR issues and instead are wasting a lot of effort on completely fanciful pipedreams. Maybe you should just buy a Lionel set and build it yourself.

Rafael said...

@ Herbie -

SF has wanted Caltrain to reach downtown for 20 years but it never had the money to do it. Only in the context of HSR + Caltrain does the great expense of tunneling underneath city streets make financial sense.

@ lyqwyd -

This was actually considered. Embarcadero is a main access route onto I-280 and is also served by two SF Muni subway lines. The SF Muni light rail yard is located between the freeway on-ramps and the Caltrain station. Huge numbers of people use Embarcadero to walk to ball games at AT&T park. There is a box sewer main along the street.

Finally and perhaps most importantly, Embarcadero is very close to the Bay - cut-and-cover would be complicated by relatively soft rock and possible flooding. Seismic safety might also have been a consideration.

@ flowmotion -

who said anything about a four-bore tube? Caltrain and HSR would share it just as they would share the access tunnel between 4th & King and the SF Central Station discussed in this post. That would require approval from FRA, as described.

The existing transbay tube isn't the bottleneck in the BART system, pedestrian flow capacity through the downtown SF stations is. Short of building a new BART tube, there are only two ways to deal with that:

(a) persuade employers to move back-office operations out of downtown SF, e.g. to Contra Costa county or,

(b) increase pedestrian flow capacity by adding side platforms to at least Embarcadero station such that trains can open doors on both sides there. The side platforms would be connected to a concourse at Fremont/Front Street via sloped moving walkways. The current TJPA design for the TBT includes a pedestrian passage under Fremont Street as an "optional" extra.

Note that BART could use a standard gauge tube if its tracks were connected to the existing BART tracks north of 19th Street via a gauge change station. RENFE uses those quite a bit to let its new standard gauge high speed trains switch to the country's legacy broad gauge network at selected locations.

Obviously, BART would need to retrofit some of its trains with variable gauge trucks. Stations served would be limited to the SF Central Station and Millbrae/SFO (via trackage rights on the Caltrain tracks, with FRA approval). With a second gauge changer at Millbrae, the SFO station could be served as well.

Note that the TJPA design probably doesn't have enough capacity to accommodate new express BART lines in addition to HSR and Caltrain. The Central Station might, because it's straight enough for BART to utilize its acceleration potential.


As for that Lionel set, maybe they have one in broad gauge for you. Nobody else wants to play with that any longer.

flowmtion said...

@rafeal -- Exporting jobs from San Francisco to Contra Costa County should be something that is opposed by mass-transit advocates, not encouraged. The city already has exported Chevron and Pacific Bell (AT&T) and that is now considered a huge mistake. The whole point of the TBT project is to increase job and population density in the area.

There does not appear to be much (if any) room for BART side platforms within the Market Street Subway footprint. Is this idea based on an engineering proposal, or is just more fanciful thinking?

Variable grade track sounds like a solution searching for a problem. Aside from all the operational issues it would create, it would depend on cost analysis of building even more complex custom BART trains versus just building the infrastructure of a four track tube.

And as far as nobody wanting to play with broad-gauge (BART), you could not be more incorrect, the system has very broad political and popular support, including at the HSRA. I am sorry your overly-wrought plans will never come to fruition, but your proposal is simply a no-go unless you can accommodate the already existing plans for BART in this corridor.

Personally, I enjoyed this blog much more when it is focused real-world political issues related to the HSR project. The tendency to delve into politically unrealistic engineering proposals is not doing the advocacy side any favors.

Adirondacker said...

That would require approval from FRA, as described.

Would the FRA care much? How many freight trains are going to be running through the tunnel?

David S said...


I believe that rafael was speaking more (ehem) broadly about gauge rather than BART specifically. Around the world standard gauge systems are being favored for new projects, even in countries with large legacy (narrow or broad) systems.

In terms of this blog. If it is simply staffed by cheerleaders, it will be derided as unrealistic. If it simply points out problem then people ask "ok smart guy, what's your solution."

Robert tends to write political/advocacy pieces. Rafael tends to look more at specific engineering problems. I won't claim to speak for everyone, but I like the current format.

(Except for the way comments are handled -- a dedicated message board is sorely needed)

Rafael said...

@ flowmotion -

a) What's good for the coffers of the city of SF isn't necessarily good for the Bay Area as a whole. Concentrating jobs in one city not only causes transportation bottlenecks, it also exposes the region to greater risk, e.g. of earthquakes.

Modern telecommunications technology (VoIP, Internet, video conferencing) allow certain types of corporations to operate offices in different physical locations as a virtual whole. It makes sense to leverage that for the enlarged talent pool alone. Add to that lower labor costs and back offices in secondary locations make financial sense for large companies.

Using existing commuter transit capacity in both directions and/or avoiding the construction of additional capacity does make sense on a regional and statewide level, even if it goes against the grain for the city of SF.

And it's not just SF: I suspect more than a few companies will shift their data centers out of Silicon Valley once HSR makes living and/or working in Fresno attractive enough for experienced data center operations staff. There are very few active faults in the Central Valley and additional power is easier to come by there.

b) Just because BART (aka the insatiable octopus) has some plans doesn't mean they will be funded. This blog is about California HSR and feeder services to it. The benefits of a standard gauge transbay tube that allows bullet trains to reach downtown Oakland and Caltrain to serve both Point Alameda and downtown Oakland are not trivial and need to be weighed against the benefits of a second tube dedicated to BART.

The side platforms idea is just that, an idea. I don't have access to detailed maps of just how much width BART already occupies, but I can make an educated guess: 15 feet per track plus 25 feet for the island platform plus 2.5 feet to either side for the concrete tunnel walls, i.e. about 60 feet. That's almost much the width of all the traffic lanes, which is about 65 feet.

However, if you include the sidewalks, the width is nearly 120 feet, plenty to support side platforms and ramps 10-15 foot in width.

The much harder question is if such structures could be excavated without causing unacceptable disruption to foot traffic on the surface, infrastructure already under the sidewalks etc. Again, I don't have access to that information and frankly, someone should get paid to figure that out.

Similarly, I can't answer if the BART tunnels could tolerate being perforated without temporary support structures that would block BART operations unless they could be removed before the next morning. In that case, one perforation per night would be installed and secured with a suitable permanent support structure, e.g. a steel frame that is later covered for fire safety. Conceptually, this would be equivalent to creating a new window in a load-bearing wall of a building - difficult but not impossible.

I'm not aware of any examples of subway stations at which trains open doors on both sides, but then most subway networks aren't nearly as large as BART, nor do they concentrate so many lines in a single core. Small wonder it is now experiencing brittle logistics problems.

Herbie Markwort said...


See the second to last page of the Embarcadero Comprehensive Station Plan. Concourse level is ~95ft, platform level ~56 ft by my estimates.

And there are quite a few subway stations that open doors on both sides. See Spanish solution on Wikipedia for details.

Adirondacker said...

I'm not aware of any examples of subway stations at which trains open doors on both sides

New York's Columbus Circle on the IND. Three island platforms serving four tracks. They don't use the center island anymore. PATH uses bay platforms at Hoboken and 33rd Street. There's an island platform and a side platform serving two tracks at Pavonia/Newport. Newark's inbound PATH track has - are you ready for this - cross platform transfers from conventional commuter trains and Amtrak on either side of the PATH track. Jamaica on the LIRR where they use the train in the middle for transfers between the island platforms in addition to the more conventional loading and unloading of passengers.

but then most subway networks aren't nearly as large as BART

Don't you mean most subway systems aren't as small as BART? Most big systems have more than two tracks through the central business district. Some of them do it by running multiple lines on different routes and some of them do it with locals and expresses and some do both.

Andrew said...

Well, all national favoritism or brand preference aside, we're talking about tunnels with curves that are the absolute tightest that any high-speed train, anywhere in the world can handle. As Clem pointed out in the Caltrain compatibility blog, that's going to mean horrendous screeching going around them and probably extra wear-and-tear on both the tracks and the trains.

Like I've said before, the more I consider it, the more I think that the new TBT is a bad idea.

Anonymous said...

@flowmotion "e. The whole point of the TBT project is to increase job and population density in the area"

No No a thousand time no. we don't want any more damn stinkin people cramming themsleves into an already over crowded city enough is enough we have 150,000 too many as it is, for comfort and quality. Come to think of it... terminate it in san jose after all. like I need to have 800 more people in my way at walgreens.

Anonymous said...

that is not the point - the point is to have a more convenient way to get to the rest of the state... for us.... not so other people can get here and stay here. The trains must only be allowed to run one way. outbound.

Rafael said...

@ Herbie, Adirondacker -

thx for the examples of subway stations at which doors open both ways. Evidently, my educated guess of 60 feet width at the platform level wasn't far off, I just added the thickness of the tunnel walls. Note that side platforms would need to be recessed as the tunnels are circular, but that's a non-issue IMHO given how wide the sidewalks are.

Note that SF Muni subway could be connected to a concourse at Market and Fremont/Front via horizontal moving walkways at level -1. The side platform gambit would be for BART only.

Regarding the size of BART: what I meant was the length of its lines (up to 50 miles, more once the extension to Santa Clara is completed) and the fact that four of the five lines have to share a single dual-track alignment through downtown SF.

The entire system has zero bypasses for express service. BART is now implementing a funky crossover in Contra Costa county.

Rafael said...

@ Andrew -

precisely, the infernal screeching noise may put quite a few passengers off the idea of taking any train to or from the TBT. Mitigation via lubrication is possible but I'm not sure if it's compatible with HSR operations.

The best solution by far is to enlarge the curve radius, but that's expensive to do in the current design because it features two curves underneath expensive real estate. If the powers that be decide to reserve the real estate under Mission Street for a future BART expansion, moving the DTX tunnel from 2nd to 3rd Street and scaling it back from a complex single three-track tube to two plain old single track tubes would help matters a great deal.

Boring single-track tunnels with TBMs and concrete rings is an old hat and can be done fairly safely unless the rock is limestone karst (aka Swiss cheese) like in Kuala Lumpur. Afaik, SF is built on highly fractured Franciscan rock, which at least doesn't have mud pockets. Subsidence risks would still be an issue, especially if more properties are affected (i.e. curve radii are larger).

Rafael said...

@ jim -

SF: the new Bodie?

Rafael said...

@ Herbie -

the Spanish solution looks useful, too. However, it requires both platforms to connect to the surface at the same location. That might be tricky for Embarcadero, the ramps I was talking about would have to make hairpin curves. Given the sidewalks are 30 feet wide, that might work for additional ramps on the east end of the side platforms, as long as they doesn't interfere with the SF Muni subway tracks that turn a corner onto the Embarcadero.

However, in a slight twist to the Spanish solution, I'd reverse the direction of pedestrian flow through the train for the rear half of the train, with appropriate signs and audio announcements to instruct passengers. Could be a bit confusing, though.

The reason is that passengers going to or coming from from the TBT during rush hour would need to both board and alight via the side platforms if there's an underground pedestrian connection via Fremont St.

Note that if Embarcadero BART is too busy to handle both commute and TBT-related passenger volume during rush hour, the whole concept of side platforms + ramps could also be implemented at Montgomery BART. The pedestrian passage to the TBT would then be under 1St Street instead. However, the distance between 1st and 2nd Street is greater than the one between Main and Fremont. Also, implementation at Montgomery would amount to backtracking for TBT-bound passengers coming from Oakland.

Anonymous said...

Rafael said...
@ jim -

SF: the new Bodie?

whatever it takes to get the population back down to normal. Hopefully with HSR more people can come and leave but not stay for good.

Alon Levy said...

Rafael: actually, concentrating jobs has benefits in terms of emissions and oil use. The economics of office buildings lends itself well to low-emissions skyscrapers in central business districts. The geography of suburb-to-city travel lends itself well to commuter rail. Even cities with semi-decent commuter rail, like New York, achieve 80% rail modal share in the suburb-to-city market. Conversely, even cities with top notch rail, like Tokyo, have low rail modal share in the suburb-to-suburb market. The total rail modal share in the Tokyo suburbs is about 40%, but that includes people who work in Tokyo, and people who live in dense secondary downtowns like Yokohama.

Adirondacker: most subway systems don't have express tracks. They achieve reasonable haul times by having interstation distances averaging about 1-1.5 km (in New York, the locals average 600-800 m), and by using rolling stock that accelerates relatively quickly.

lyqwyd said...


sure there are engineering issues with running it up embarcadero, but I don't think they are particularly worse than any other solution provided, especially considering it will only run along 2-3 blocks of Embarcadero, from Townsend to Main. And it would solve the major problem of curve radius.

Embarcadero is a wide street, and has wide sidewalks on both sides, and is relatively undeveloped in the area I'm proposing. Construction could possibly done on only 1 half of embarcadero (preferably the inner side, away from the bay) without disturbing the train if the sidewalk is dug up as well, and traffic could be one way during rush hour. The sewer and the water issues would make it more difficult, but could certainly be dealt with. if the tracks would require both sides to be dug up, they could be done sequentially, which would still allow half of Embarcadero to be used by cars during construction.

There may be other issues that I'm not aware of, but so far it still seems like a good solution to me.

lyqwyd said...

@jim "No No a thousand time no. we don't want any more damn stinkin people cramming themsleves into an already over crowded city"

jim, please leave out the "we" in that statement, you may not want more people, but I most definitely do. I would love to see the population of SF double over the next few decades.

Although it's highly unlikely my desire will be reached, you can be assured SF population will continue to grow.

Now I agree it shouldn't just be for the rich, there needs to be much more middle-class housing developed here, and family oriented as well.

Rafael said...

@ jim, lyqwyd -

back in 2005, CHSRA actually had Cambridge Systematics collect state and academic research data for a county-by-county forecast of demographic trends, as a foundation for ridership forecasts. See p31 here.

While the absolute numbers are much less certain than a cursory glance suggests, net population growth in SF county is expected to be on the order of 1.1-1.2% per year between 2000 and 2050. Mind you, this study was done before the mortgage bubble burst.

@ lyqwyd -

I agree with you that Embarcadero and Main, with trains entering the TBT from the East, would make for more generous curve radii - resolving many of the problems associated with the throat. Six dead straight full-length platforms and 2-3 dead straight tail tracks under each of Minna and Natoma would be possible.

I was merely citing the reasons TJPA gave for discarding this option, in addition to the greater cost due to the greater length. I don't think that should be the primary consideration though, since skimping on infrastructure that will be around for 100 years is a bad idea.

Anonymous said...

jim, please leave out the "we" in that statement, you may not want more people, but I most definitely do. I would love to see the population of SF double over the next few decades" Omg why on earth would you want that. TI will do nothing but create an impossibly unpleasant quality of life. It will be impossible to move around without having people in your face everywhere you go. The park will be overcrowded, the beach will be over crowded, union square/market st already impossible to walk through will be unbearable. And forget about muni. Not to mention people coming here from other places trying to re arrange evrything and ruin the place. Cramming more poeple does nothing but deteriorate the quality of life that has been going down hill already for the past 15 years or more. I guess you are new here and don't know how nice ti used to be when it was livable, affordable, comfortable and laid back, and you could see something besides highrises blocking everything. it why we have such an anti development board of supervisors because many people - who are not that far left on other issues - still vote for folks who will save the city from overdevelopment. growth will come but it will be made as slow as possible by san franciscans.

Anonymous said...

there is no way this city can support 1. million people. no way in hell.

Anonymous said...

(1.5 million)

Anonymous said...

i mean not be off topic too much but another 800k at two people per unit would mean building over 1000 "one rincon hill" s and what neighborhood is going to welcome all this growth? none of them.

Alon Levy said...

Rafael, 1.1% a year is very doubtful. It implies 11.6% per decade; SF didn't even grow that fast in the 1990s, which were a decade of relatively fast growth for old global cities. The housing bubble has collapsed in the SF suburbs, but SF housing prices have barely come down - I have no idea what effect it'll have on relative city vs. suburb population growth.

lyqwyd said...

"Omg why on earth would you want that. It will do nothing but create an impossibly unpleasant quality of life."
Two great cities with great quality of life with way more population density than SF are Paris & Manhattan. SF is 49sq miles with 800k people (17K people/sq mi), Paris is 33sq miles with 2.1M people (64K people/sq mi), and Manhattan is 23sq miles with 1.6M people (70K people/sq mi). I've never lived in either, but been to both and enjoyed them immensely.

"It will be impossible to move around without having people in your face everywhere you go"
Both Paris and Manhattan are easier to get around in than SF, as long as you don't plan on driving everywhere. I've never driven in either, but SF is certainly no driver's paradise, I avoid it if at all possible. Having a more densely populated city will result in better public transit and more walkable neighborhoods.

"another 800k at two people per unit would mean building over 1000 'one rincon hill's"
If that were the case why don't we have 1000 'one rincon hill's to support the current 800K people that live in SF? There are many ways to provide the necessary units to add that many people. There's loads of room to grow in SOMA, as well as some other regions of the city, in particular the old Hunters Point naval shipyard. There's certainly a lot of cleanup that needs to be done before any development can happen there, but I certainly hope they increase the density from the current plans when it's finally ready for development. Plus the assumption of only 2 people per unit is way too low in my opinion, that doesn't leave any room for children. I would like to see lots of new mid-rise development in the 2-4 bedroom/unit realm, not a bunch of high-rise luxury development... I believe that would help the affordability for middle-class folks.

In all honesty, I don't expect SFs population to double in 20-30 years, but I sure would love to see it happen. But even at only 1.1% annual population growth rate SF would double in population in 65 years.

Adirondacker said...

most subway systems don't have express tracks.

But most subway system don't attempt to be intercity rail at and local transport at the same time. They don't even attempt to be suburban rail beyond the close in suburbs. And they don't try to do that on two tracks in downtown.

Chicago has three and four tracks in places... Brown Line at least ... Red Line too? And since you can practically spit between stations in the Loop, at least in the Loop anyway, they aren't that far apart. And nobody is talking about using the Red Line to get to Milwaukee.
If you were to suggest to people in Yardley or Doylestown that the Broad Street line would be a better option, they'd back away slowly and speak softly. And if you suggested to people in Norristown that they could have a one seat ride to 5th and Market but would have to give up express service, they wouldn't have a polite response. I'm sure METRA, MARC, VRE, and MBTA riders would have similar ones if you told them they would have to make every last little stop along the way on their commute to downtown.
The people in the Bay Area can't seem to think beyond BART. BART isn't a good solution for Santa Rosa. It's probably marginal for Pittsburgh and Fremont. Dragging it from Fremont to San Jose might make sense to get commuters from the southern ends of the East Bay to SJ but using it for San Jose to Oakland.. makes me laugh. Giggles. All sorts of hilarity. Especially when there's already existing service that could be upgraded much more cheaply. And that opens the possibility of running trains to places BART doesn't go.

Anonymous said...

well if they stick em down in hunters point and givem em a one way south bound train fine. But I really think that california's future growth needs to be distributed in such a way that the other cities have to do their share. they have way more room. sacrmento, fresno, bakersfield, merced, riverside, san bernadino, chico, redding - all them have unlimited room to grow. send em there... they can take the hsr if they want to come visit, then take it home at the endof the day. If I thought manhattan was a pleasant place id be living there.

lyqwyd said...

suburban and exurban development is not an ecologically sound strategy, it promotes more driving, which leads to higher gas prices, it takes away farmland, is more energy intense, is more resource intensive (more asphalt laid per person) and hurts watersheds. Development should be focused in the denser areas.

Anonymous said...

Thats too bad - you can't ruin my city. You don't have to have sprawl you have to make the other cities more dense - go build some rincon towers in fresno. In san francisco we will protect our neighborhoods. always have, always will. That's the way it is. period. the city is not here for outsides to exploit for their own profit. We have done our part. Let some other places do theirs. Any and all development in sf is up against a fight, every time. just so you know.

Anonymous said...

stricter height limits are making a comeback soon, too. My advice to developers, go someplace where you are welcomed, you'll save time and money.

BruceMcF said...

jim said...
"Thats too bad - you can't ruin my city. You don't have to have sprawl you have to make the other cities more dense."

And, further, what matters is not metropolitan average density, what matters is local density. Replacing a tract of half acre separated suburban house with a cluster of stacked townhouses around a mixed used block around a regional train station, with a dedicated light rail or Aerobus or Rapid Streetcar line connecting at that train station is anti-sprawl development.

The idea that fighting sprawl means everyone moves into the 20% or so of the country has real urban densities and the ability to more or less support a public transport system is simply under-ambitious. Its only nibbling away at the edges of sprawl, instead of making a full fledged attack on sprawl at its heart.

"A bit less sprawl" is just not good enough. We need to eliminate sprawl development, and that means going out and establishing counter-sprawl development in the outer suburbs, with clustered suburban village development around transport nodes and reversion of some of the outlying suburban development to truck gardening and green space.

Anonymous said...

yes - the answer is to draw a boundary around your city - whichever one it may be - and force all development out side the boundary creating plenty of reserved farmland open space and wildlife preserve in between each mid sized urban area.

Unknown said...

yes - the answer is to draw a boundary around your city - whichever one it may be - and force all development out side the boundary creating plenty of reserved farmland open space and wildlife preserve in between each mid sized urban area.

Then you just get London, where the city leapfrogged its surrounding greenbelt (thanks in part to good access to commuter rail) and continued to sprawl into the English countryside.

Although I don't understand your opposition to greater density in SF. SF's current medium density paradigm simply benefits middle class property owners, and who cares about them? What's in it for the likes of Eli Broad? Ultra high density megaprojects are the best way for the rich to get richer, so clearly that's the approach we should take.