09 November 2008

The Big Picture

To people who live on the San Francisco peninsula, High Speed Rail will be defined by four principal characteristics:
  • 4 tracks all the way, from San Jose to San Francisco
  • Full grade separation, i.e. no grade crossings
  • 125 - 150 mph top speed (far lower than the 220 mph capability of HSR)
  • Electrification with a 25,000 volt overhead contact system
According to Quentin Kopp, chairman of the California High Speed Rail Authority, the peninsula line could be operational in 2015.

What will that look like where you live?

We can try to draw the big picture from the CHSRA's Environmental Impact (EIR/EIS) documents for the Bay Area, published in May 2008. There's lots of detail in the report and appendices.

A map of the peninsula from a 2004 EIR/EIS document (at right) summarizes where the peninsula tracks are planned to run at-grade, in tunnels, or in elevated or sunken sections. The CHSRA also provides a more recent, interactive Google Map. These maps are clearly preliminary, as anyone with detailed local knowledge will attest; they will be fleshed out in the next few years during the detailed engineering phase.

HSR plans call for building most of the new peninsula tracks at ground level, or in elevated / sunken sections as labeled in the above map. Cross sections of these configurations are provided, with the most common shown below.

Ground level 4-track section. Caltrain already has these (minus the overhead wires) in Brisbane, Redwood City and Sunnyvale, to enable Baby Bullet service. The ROW width is about 100 feet, including service access roads used mostly for trimming vegetation. This configuration is labeled A.38 in the map above.

Elevated 4-track section. Where space is available, this can be built on a wide berm. Where space is not available, retaining walls are used as shown in the figure, keeping ROW width to within 75 feet (with external access presumed). Labeled A.39 in the map above.

Sunken 4-track section. The ROW width is within 75 feet (with external access presumed). Labeled A.39 in the map above.

Caltrain has some additional dimensioned cross section drawings in Chapter 2 of their electrification EA/DEIR (see in particular Figure 2.3-3).

At any location, the choice of configuration will depend on a variety of factors:
  • Grade separations, where the height of the tracks is constrained by the presence of an under- or overpass
  • Available right-of-way width: some configurations consume more space than others, with possible eminent domain impact
  • Noise and aesthetics (sunken is preferable on both counts)
  • Expense: anything involving lots of earth moving and pouring of concrete will automatically cost lots of money. That is certainly bad for the taxpayer, although the large construction firms that design these projects sure don't seem to mind.
How will the arrival of HSR alter existing Caltrain tracks, stations and crossings? In future posts, this blog will focus on some unique situations at various locations on the peninsula.


  1. Another issue is constructability. Remember Caltrain will continue operation throughout the construction period. Building a 4 track rail bridge would require multiple phases of construction. This makes the construction cost much more expensive by having to build something that would be torn down, and then make room for another structure.

    I would like to know whether HSR and Caltrain can co-exist with less than 4 tracks for the whole corridor. This requires an operating plan, which HSRA doesn't have today. I also would like to know what are the travel time penalties by reducing top speed to 90 mph and whether improvements can be done elsewhere cheaper to compensate the loss of speed on the Peninsula

  2. Hi Andy, that's a good question and an important issue. Keeping Caltrain running while the grade separations were built in San Carlos and Belmont was pretty messy, and will be the subject of a future post.

    The HSR docs have a basic operating plan (how many trains per day).

    On an unrelated subject, please drop me a line: my first name at tillier dot net. I have something I've been meaning to send you, but I don't have your e-mail address.

  3. I have a bunch of questions that I was wondering if anyone could answer for me, this seemed like the appropriate time. Some might be stupid but I've been wondering about them since I became obsessed with the HSR project.
    1) So from what I can see from the extremely informative Compatibility Blog, the plan is for 4 rails wide from San Francisco down to at least SJ Diridon, correct? I've been confused as to how the HSR train will actually get out of the bay area and onto its own dedicated track through the central valley. Looking at the pictures on the site, the HSR train will share the center two tracks with Caltrans Express lines and the outer two tracks will be for normal Caltrans service and freight.
    2) Will it become a problem sharing a set of tracks with Caltrans or will there be scheduling to ensure that HSR has a straight, unhindered shot down to SJ?
    3) Looking at the example of Millbrae, will all stations along the HSR line require 4 tracks to allow for full speed express trains traveling through the station and local trains or can it work with only 2 tracks?
    4) If HSR shares its tracks, will the heavier Caltrans trains damage the tracks at all and require the HST to slow as the years progress? 5) Will all 4 tracks be upgraded during the Caltrans electrification process to allow the HSR to run on them or are they already ok for the speeds the train will be doing through most of the bay area (~125 mph)?
    6) Which train setup do you think Caltrans will adopt after electrification when it is finished in around 2014 (is this the expected completion year?), EMUs or simply upgrading the locomotives to electric units and keeping the same passenger cars?

  4. (1) the 4 tracks are shared to SJ. Beyond there, Caltrain has no plans to electrify. The HSR tracks to Gilroy and beyond will be separate from Caltrain, if I recall.
    (2) the schedules would probably be coordinated such that HSR has a straight shot.
    (3) they will all require 4 tracks
    (4) Caltrain as it exists (slow, diesel, heavy) will be replaced by euro style EMUs (fast, electric, lightweight and fully compatible with HSR on the peninsula)
    (5) Caltrain electrification will probably have to be redesigned, and much of the track rebuilt / realigned for higher speeds. The track is currently only good for 80 mph.
    (6) EMUs are the way to go because they provide better start/stop performance. The gallery junk heaps will be scrapped, and the heavy FRA Bombardiers can go serve Gilroy.

  5. The only HSR I've ridden on is in France... which from Paris to Marseille and Strasbourg to Paris is really nice and fast. Between Paris and Bordeaux is slower (according to random online map because only half the way is high speed line).

    Is the CHSR going to be comparable to the French services in speed per distance? I agree with getting the best speeds for the money but I think there needs to be an open process of the trade offs of speed and price.

  6. * TGV starting at Paris (got hours from their website)
    * Distances from city-to-city Google Maps

    Bordeaux (583km) 3h04 - 3h35
    Marseille (776km) 3h10 - 3h22
    Strasbourg (487km) 2h19
    Lyon (466km) 1h57
    Bruxelles (305km) 1h22 (Thalys)

    * Distances using track miles on website
    San Francisco to Los Angeles (381mi/613km 2h38 (432 track miles)
    San Francisco to San Diego (501mi/806km) 3h56 (616 track miles)
    Sacramento to Los Angeles (385mi/619km) 2h17 (412 track miles)

    I used the Google Map miles between the two since track miles seem like a bad way to calculate... I suppose the numbers are about the same... although CA seems to fall a little short of the newer, faster TGV tracks probably in part because they are trying to incorporate more cities making some track miles significantly greater than Google driving directions.

  7. @ Clem -

    So you think Caltrans will go the expensive but ultimately better solution for the future and scrap every part of the current trains but move the baby bullet trainsets to the SJ to Gilroy route and go and buy completely new bilevel EMU units? Sounds like a better solution to me. It would be hard to simply add electric locomotives to the current crap gallery cars. The newer all EMU trainsets would allow faster service with much higher comfort with less maintenance in the future.

  8. Would it at all make sense to run the peninsula HSR from Santa Clara, up along Lafayette St. towards Alviso and then along the berms of the old salt ponds and on viaducts along the edge of the bay until it can rejoin the ROW next to the Dumbarton Bridge and through East Palo Alto and East Menlo Park to a station in Redwood City. If this can be done with minimal environmental impact to the bay, it would bypass some difficult parts of the Caltrain ROW, such as Mountain View, and would stay away from many NIMBY problems. It could also split at Alviso with a branch to Oakland.

  9. I think this got to have 4tracks may have to go. With Caltrain also having Euro standard train sets and FRA ok this would save huge amounts of money and headaches. Build out 4 tracks where its easy and cheap to make up time..as you said ..KISS