11 August 2018

New SF Caltrain Terminus Opens at 0 tph

Zero trains per hour (tph) is the inaugural Caltrain service level at San Francisco's new Transit Center, which opened to the public today after a decade of construction. The grand opening of the center, with its expansive $400 million basement featuring ghost tracks, ghost platforms and a ghost passenger concourse will no doubt crystallize the increasingly urgent transportation need for the downtown extension (DTX) of the peninsula rail corridor. Only then will train service increase beyond the current level of zero tph.

Huge opening day crowds at the Transbay Transit Center. Photo by Adrian Brandt.
Why build DTX?

Simple. Within a half mile radius of the Transit Center, there are more jobs than within a half mile radius of every station along the peninsula rail corridor from San Francisco 4th and King all the way to Gilroy, COMBINED! Even before high speed rail shows up, this is a piece of infrastructure that makes perfect sense. Or does it?

An epic opportunity for transit funding extortion

The clear (and, as of today's opening, agonizingly present) need for the DTX sets up a deliciously fat and juicy prey for the transportation-industrial complex, which you can think of as a hungry snake. Here we are, in a strong economy, in one of the richest cities on Earth, facing a specific and obvious transportation need: they can name just about any price. The latest estimate for the biggest meal that the snake can swallow is six billion dollars, and that's only the start. Scope creep, dizzying amounts of contingency cushioning, and construction change orders are sure to drive it far higher. Civil engineering megafirms, labor unions, and complacent and poorly coordinated government agencies are salivating at the prospect of feasting on the DTX. The bigger it gets, the more sated and comfortable everyone will be, with the notable exception of the suckers who pay taxes and ride trains.

The DTX project needs a major cost cutting exercise

"It is difficult to get a man to understand something, when his salary depends on his not understanding it." This insight by Upton Sinclair applies to any attempt to reduce the scope or optimize the cost effectiveness of the DTX project. There isn't and probably won't be a true will to do it, but in a pretend world where the interests of taxpayers and riders came first, where might you start cutting scope?
  1. Delete the Pennsylvania Avenue tunnel extension. There is a perfectly serviceable tunnel already available. Engineering acumen should be brought to bear to overcome the (otherwise delightfully profitable) constraints of building a new trenched grade separation by figuring out how to shore up I-280 during excavation; how to cross the SFPUC's giant new sewer; how to duck under 16th street using a steeper 2.5% grade than the train people would prefer; and how to build temporary "shoo-fly" tracks under I-280 during construction now that the area is hemmed in by fresh UCSF construction. The usual paint-by-numbers engineering that deploys freight train design standards as "constraints" shows this to be categorically impossible, but is it really? Sharpen your pencils.
     
  2. Delete the mezzanine level at 4th and Townsend. Station mezzanines are a knee-jerk (and delightfully profitable) design feature of every recent piece of rail infrastructure in the United States. Wedged above the tracks, underneath, in the sky or in a cavern, mezzanines tend to sprout everywhere. In this case, a mezzanine makes passenger access more circuitous and pushes the track level much deeper, increasing the depth of excavation. The mezzanine and station become an enclosed underground space, triggering an avalanche of fire safety requirements that greatly increase cost and complexity, with all manner of vent structures and evacuation shafts. The right answer is simple, direct and free-flowing access from platform to street, and an open station ceiling that vents to the street through a slot built into a raised median on Townsend Street-- as wide as necessary to treat the structure as an open station under fire safety regulations.
     
  3. Daylight as much of the shallow Townsend Street portion of the alignment as possible, with a central median vent slot (just like in Los Angeles on the Alameda Corridor, where three of the nation's busiest diesel freight tracks are concealed beneath the street with a vent slot as narrow as six feet). This configuration has the potential to simplify the engineering considerations and costs related to fire safety, and even improves rail operations: without the onerous fire safety requirement of having only one train at a time occupy each tunnel ventilation section, operation of the entire DTX becomes less constrained.
     
  4. Slim down the three-track tunnel, another one of Sinclair's salary considerations, to two tracks instead of the planned three. The Rail Alignments and Benefits (RAB) operations analysis, carried out by a premier Swiss rail operations consultancy, concludes on page C-68 that "Under normal conditions, only two tracks are required in the tunnel leading up to the TTC to operate the analyzed service plans. More detailed analysis is recommended to identify the most effective approach to provide infrastructure redundancy (e.g. the proposed third tunnel track) to help mitigate the potential effects of major service disruptions." The clear implication here, artfully worded so as not to upset Sinclair's salary men, is that a third track is not necessarily the best or only approach to achieve infrastructure redundancy.
     
  5. Add three 400-meter underground storage tracks, feeding in towards the Transit Center instead of the peninsula, along the northwest edge of the existing 4th and King station footprint. The fire safety requirements for this underground infrastructure would be less stringent because it would not be occupied by passengers. With beefy foundation columns bored down to bedrock to straddle this yard, the entire footprint of the site can still be redeveloped above grade, safeguarding San Francisco's desire to use "value capture" from this increasingly coveted parcel to finance DTX construction. The resulting train storage capacity is far more conveniently located than the remote yard sites currently proposed at Oakdale or Bayshore, reducing long-term operating costs. Even skyscrapers can be built on top of train storage: see Hudson Yards.
     
  6. Rationalize the Transit Center approach tracks to speed up train movements. The throat of the station has been identified as a key bottleneck for train movements (see RAB operations analysis page C-96, "Key Findings of Conceptual Planning"--and recall that you read it here first). An optimal layout has been identified that better enables concurrent arrivals and departures of two trains (see page C-117 of same). Precious seconds saved in the station approach can increase the traffic capacity of the DTX and make it more resilient to disruptions.
     
  7. Don't use exotic and expensive tunneling methods when their sole purpose is to keep businesses along the DTX route healthy during construction, by avoiding cheap but disruptive cut-and-cover methods. The intent is noble, and the recent impact of Central Subway construction in Chinatown is painful and fresh in our minds, but this sort of thing rarely pencils out for anyone but Sinclair's salary men.
Only after a draconian cost cutting exercise might it begin to make sense to build the DTX. At a price point of six billion dollars for a couple of miles of tunnel, we regretfully should keep service levels at zero trains per hour.

30 comments:

  1. 2 and 3. The notion of building the Mission Bay station underneath Townsend Street is fundamentally wrong as there is a hugely capacious piece of 100% unemcumbered railway station real estate just a few feet to the east of the street, namely the existing Caltrain Fourth&King/Townsend terminus.

    A fully functional (three through platform tracks with full 420m platforms, fourth optional non-platform bypass track) fits very comfortably within the existing Caltrain station block between Fourth Street and Sixth Street, with only a small amount of intrusion (ie partially decking over one platform) into the Townsend Street right of way.

    Such a station in a trench can be completely open to the sky aside from bridging roads and pedestrian passes -- desirable in nearly every way, and especially from construction cost and crazed fire safety perspectives.

    The concept of a "vent" for fire fumes to escape is a total non-starter, Clem! We expect better of you!

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    1. The implicit requirement that has emerged over the last decade (after you drew up your otherwise excellent DTX plan) is that the DTX configuration, whatever it may be, must free up the area between 4th, King, 7th and Townsend for commercial and residential redevelopment. Your notion that this parcel is “100% unencumbered” is very much outdated.

      NFPA 130 does allow for passive measures to control the fumes from a station fire. The sort of CFD analysis required to verify the safety case is neither mysterious nor difficult. The detailed design of a vent slot just needs to be analyzed, and I have no doubt that it could work.

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    2. Indeed it does... https://youtu.be/ituY2-Yqm3U?t=1893.

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  2. 5. Storage tracks are huge distraction, driven entirely by the need to put concrete (= sweet sweet sweet billions of pork) ahead of sanity and operations (= non olde tyme commuter railroading.)

    If there really were a need to park out-of-service trains in expensive CBD real estate in expensive below-grade locations (hint: there isn't), then at least two locations readily suggest themselves:
    (a) The Transbay Terminal, featuring 6 platform tracks, when three would be more than adequate to cover reduced off-peak levels of service.
    (b) Mission Bay Station, featuring 3 platform tracks and perhaps a bonus bypass track, where two would cover all service (the third and fourth are nearly entirely driven by the insane, inexcusable, execution-worthy, 100% Parsons Transportation Group fault, hideousness of the unworkable Transbay approach throat with idiotic support columns exactly where crossovers could easily have gone.

    If that fails, a little further out (doesn't affect operational conflicts, but does affect deadhead time) alongside the tracks, on a berm, under the freeway, a bit south of Evans in SF is easy and workable. And amazingly enough, even identified as such by the sub-cretins involved in the "Rail Alignments and Benefits" scam-fest.

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    1. The sub-cretins involved in the "Rail Alignments and Benefits" scam-fest totally outdid themselves here:
      See "Building structures and foundations removed and reconstructed" on page 4
      http://default.sfplanning.org/Citywide/railyard_blvd/RAB_TechReport_052118_DRAFT-AppendixB.pdf

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  3. What do Parsons etc really have to gain from over-specing DTX as opposed to just charging above market costs for sensible infrastructure as proposed by you? Say that comes to 3 billion. Then they could hypothetically still get the extra 3 billion by building sensible but overpriced infrastructure elsewhere, be it on Geary or wherever, for the same cost from there perspective? Does it increase their margins to over-scope a single project and then overcharge, compared to building two projects and similarly overcharging?

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    1. Larding up a public works project is an art, because government scrutiny is high (just as it might be in defense procurement). One of the most effective strategies in this case is scope maximization. Gold plate the s*** out of a product that barely meets the threshold functional requirement.

      Perhaps the predator analogy can give one answer. Going after prey is an expense of resources with each attempt having a low probability of success, which favors going after fewer, bigger meals.

      Another explanation is “too big to fail” thinking, as so perfectly expressed by former SF mayor Willie Brown: "News that the Transbay Terminal is something like $300 million over budget should not come as a shock to anyone. We always knew the initial estimate was way under the real cost. Just like we never had a real cost for the Central Subway or the Bay Bridge or any other massive construction project. So get off it. In the world of civic projects, the first budget is really just a down payment. If people knew the real cost from the start, nothing would ever be approved. The idea is to get going. Start digging a hole and make it so big, there's no alternative to coming up with the money to fill it in."

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  4. Don't discount fire. The assumption is that any station will be full of passengers and trains when a completely flaming trains comes into the station (assume WORST BAD film scenario). Freight corridors and passenger corridors are two different things. Alameda freight corridor in LA was not a passenger project. Sorry.

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    1. Clearly, an open trench would not require forced ventilation, while a closed tunnel would. As you vary the amount of cover over the trench from zero to 100%, the question becomes at what percentage trench cover can the fumes no longer be acceptably evacuated by natural convection. I claim (without CFD analysis) that this figure is north of 80% and that the chimney effect can be harnessed to evacuate fumes passively, using ceilings that slope towards the slot. I recognize that passenger vs. freight facilities have different requirements, but the fire physics are the same... somebody should look into it before we spend all those billions.

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  5. Here is how to get the job done in 4 years for $2B: https://youtu.be/v-QYQJYDTt4

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    1. Bored tunnel costs: https://tunnelingonline.com/central-subway-tunneling-project-contract-1252/

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  6. This assumes SF has the political will to actually build a DTX in the first place. I'd better apply to BART's new subway into Diridon, which has the same basic issue (expensive TBMs or inexpensive trenches, fire safety, mezzanines everywhere). Same for the HSR bridges over 280 and 87 (and of course Diridon itself), and the proposed trench/tunnel to run between the Capitol Expy and Metcalf. All of which are will be built long before the Transbay Terminal accepts trains.



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    1. Fact check:

      $188M 1.5 miles of twin-bore tunnels
      $30M portal
      Two $10M TBMs
      Four cross-passages
      Total $233.9M

      https://www.sfcta.org/sites/default/files/content/CapitalProjects/images/Central_Subway/CentralSubway_factsheet_042017.pdf

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  7. The fire requirements that only one train can be in the tunnel between roughly 7 & Townsend and Transbay terminal is new to me. You might as well single track leading into Transbay at that point.

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    1. Ventilation Concepts for Meeting One Train Per Vent Zone

      NFPA 130, Section 7.2.5, states “The design and operation of the signaling system, traction power blocks, and ventilation system shall be coordinated to match the total number of trains that could be between ventilation shafts during an emergency.”

      Transit and rail agencies typically develop strict sets of procedures to govern the backing of train movements because of safety reason. These procedures would also tend to elongate the time needed to back trains during a fire emergency. The extraction of non‐incident trains cannot be easily accomplished in the same time frame as the activation of the ventilation response. Therefore, the best protection to passengers and crew members is to allow no more than one train in a vent zone.

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    2. Sorry if I created any confusion, but there are something like 4 or 5 ventilation sections in the tunnel. You can read all about it in the RAB study appendices.

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    3. And that, ladies and gentlemen is precisely why the Transbay tube (and just about every properly designed twin-bore tunnel in the World) does not require a vent shaft every 400 yards...

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    4. That also explains why we see more bores and less large tunnels, right?

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    5. Of course, the Transbay Tube has two central galleries for its entire length. A lower level for maintenance access and to evacuate people from where the tracks are, and a second level with conduits and air ducts.

      The problem here comes with the three track bored tunnel from Fourth to the TTT. With one big bore, there's no second tunnel to evacuate to through cross passages in the event of something smokey.

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    6. Cool old 1967 newsreel-style video showing Transbay Tube assembly and BART system construction.

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  8. OT: Buying land for HSR in the Central Valley could get a lot cheaper soon... http://www.sandiegouniontribune.com/opinion/editorials/sd-trump-trade-war-central-valley-agriculture-20180816-story.html

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  9. Came across double-span catenary design on the NEC: https://youtu.be/Jl_7T1mlb6Q?t=141
    Watch what happens to the contact wire on the opposite track (not quite as bad in the opposite direction).
    I guess everything should be just fine as long as they don't allow simultaneous fast trains in opposite directions(?)

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  10. I used to be a die-hard "build the DTX" proponent. But after commuting on Caltrain for the past year, I'm questioning it a bit. I don't see where the new people who want to travel to the financial district are going to fit. The (non-local) trains are all totally packed during commute hours as it stands now. It is an extremely unpleasant experience commuting on Caltrain these days, sadly. Not as bad as BART, at least not yet, but headed in that direction.

    I'm still a proponent of DTX, but Caltrain needs to address capacity ASAP before it drives people away for good. It doesn't appear electrification is really going to help much, at least from a number of seats perspective. Perhaps with electrification local trains will become faster and less painful for commuters, and take some of the load off of the express trains. The local trains now are generally pretty empty.

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    1. Agreed. Caltrain has most of the money in hand to extend the new EMU fleet to 8 cars at or very soon after entry into revenue service. Two considerations before exercising the option: a big chunk of that funding hangs in the balance of Prop 6 this November, and Stadler probably can’t increase their production rate with their US supply chain barely ramping up.

      Recall Caltrain’s plan also includes extending the bullets (which will initially remain diesel) from 6 to 7 cars once the EMUs free up the fleet.

      If HSR does eventually connect to the Central Valley, then I think Caltrain will need to plan for 12-car EMUs. Until that happens, with so-called “HSR” captive on the SF to Gilroy segment per latest business plan, it makes zero sense to run “HSR” with anything else than additional Caltrain EMUs.

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    2. For sake of argument, let's say that capacity of a 5-car diesel is about same 6-car EMU. The faster braking and acceleration takes you from 5-trains to 6-trains per hour, so 20% improvement. Going from 6-car EMU to 8-car EMU gets you another 33% improvement. As Clem said, funding for 8-car EMU is almost all identified, so once electrification is complete, capacity can improve over next few years to 6 tph of 8-car EMUs.

      Beyond that, as Clem said, you could go for 10-car or 12-car EMUs, but probably only at select stations, so probably only for Baby Bullet runs.

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    3. Note that converting the remainder of the bullet fleet from diesel to electric is not yet funded. We are only talking about a fleet mix of 17 EMU8’s and 8 or so diesel 7-car consists for the 2022 timeframe.

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    4. I hear that SEPTA has some clapped out Silverliners they may be willing to sell cheap. And Metro North some M2/4/6s. They may have turned them into reefs, There are electric locomotives laying around too. I think NJTransit may still have some ALP44s that have been out of service for a really long time. AEM7s?

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    5. Probably not worth bringing on another new clapped-out subfleet after having just disposed of one (F40s + early galleries), especially when you consider the massive cost of PTC retrofit. The diesel stop penalty is large, but the bullets have few stops so it all works out.

      Incidentally, ex-Amtrak AEM-7 #938 is soon coming here as a lone test locomotive.

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  11. The gift keeps on giving: https://www.smdailyjournal.com/news/local/caltrain-receives-m-grant-for-positive-train-control-project/article_6a328a08-a744-11e8-bc75-b31c4a88bdaf.html

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  12. Guess what Metra did after receiving a single bid for their new railcars: https://www.progressiverailroading.com/mechanical/article/Metra-to-reissue-rail-car-RFP--55147

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