California High-Speed Rail Alignment Questions

The most contentious technical issue about the California High-Speed Rail project is which alignment to use to get from the Central Valley to the Bay Area. The two options are Altamont Pass, roughly paralleling 580, and Pacheco Pass, much farther to the south. A summary of all alternatives can be found on page 115 of the revised Bay Area-Central Valley EIR. For more detailed examination of the alternatives, see the old EIR: the base Altamont option is on pages 903-4, the base Pacheco option on pp. 969-70. Although Altamont is somewhat longer, the two alignments are about even on travel time from Los Angeles to San Francisco (in fact, Altamont is 2 minutes faster).

The basic tradeoff is that Pacheco is somewhat faster for LA-San Jose and serves San Jose and San Francisco on one line, while Altamont is much faster for Bay Area-Sacramento and requires less construction overall and has separate branches to San Francisco and San Jose. Overall, Altamont is superior because of its advantage for travel from the Bay Area to Sacramento and the Upper Central Valley (except Merced, whose commute ties to the Bay Area are weaker than those of Modesto and Stockton). Transit activists and environmentalists either preferred Altamont or did not have an opinion. However, San Jose didn’t want to be left on what it perceived as merely a branch, and lobbied hard for Pacheco, and as a result Pacheco became the preferred alternative; in addition, unlike the NIMBYs on the Peninsula, the NIMBYs in Pleasanton and Tracy complained about HSR early.

A third option is to go via Altamont but enter San Francisco from Oakland via a second Transbay Tube (old EIR, pp. 957-8). The EIR projected it to have the highest ridership, since it serves both San Francisco and Oakland on one branch and has the shortest LA-SF travel time. It was rejected because a second tube would be very expensive, though in fact the EIR pegs the cost of this option at a few hundred million dollars more than the base Pacheco and Altamont options; urban construction along the Caltrain line is expensive as well. In a crunch trains could continue along an electrified but not otherwise upgraded Caltrain line at lower speed, reducing cost, but by a similar token people could transfer to BART at Livermore under any Altamont option and at West Oakland under a second tube option. However, should a second tube be built anyway to relieve the near-capacity BART tube, such an option would become far and away the best, making all others redundant.

The choice of Pacheco became one of the galvanizing features of the technicals in California, who without exception preferred Altamont. To answer concerns that Bay Area-Sacramento travel has to be served, both the HSR Authority and various politicals have proposed a cure that’s worse than the disease: build a high-speed commuter overlay along Altamont (the official version) or the I-80 corridor used by Capitol Corridor trains (consensus among pro-Pacheco blog commenters, see e.g. this map with a second tube just for SF-Sacramento trains).

Pacheco itself is mildly defensible. It would arguably have been superior if Sacramento did not exist, and I-80 would have been the better alignment for SF-Sacramento service if LA did not exist. But given that LA and Sacramento both exist, Altamont’s ability to serve LA, Sacramento, and SF with just one expensive bit through the pass becomes more valuable. If Altamont is built, there would be no point in a Pacheco overlay, whose primary use would then be a frankly uncompetitive connection to Monterey. But Pacheco leads to demands for an overlay service, one that’s almost certainly too expensive to build just for Bay Area-Sacramento travel.

The Capitol Corridor, the other option for SF-Sacramento service, is too slow. With a bus connection from SF to Emeryville, the fastest service takes 2:08 from downtown SF to Sacramento. Even Pacheco beats that: express trains detouring through Gilroy and Merced will nominally take 1:53; service via Altamont is a little more than an hour . For SJ-Sacramento travel, it’s 3:05 on Amtrak and 1:24 via Pacheco. Substantial upgrades are impossible since Union Pacific owns the track and restricts passenger trains’ performance in order to remove a headache for freight operations. The remaining option is to build passenger-dedicated bypasses, at considerable cost and with little benefit over doing it right the first time.


  1. Danny

    I agree with the Altamont route because I believe that shorter traffic with less competitive air links will be more important to serve. In other words, it would be more important to link Modesto/Stockton with San Jose, or San Jose with Sacramento, or Sacramento with San Francisco, etc., than it would be to give San Jose a slightly faster access to Los Angeles.

    That being said, the Capitol Corridor route has a lot of potential for speed, given that it is a much more direct route with less hilly terrain. If they were to try to speed up the route…or even let it be taken over, then the Altamont route could quickly lose its appeal.

    I wouldn’t even be surprised if Amtrak California tried it. They have been a bit more innovative and better managed than the other Amtrak, and they have also felt like they have been thrown under the bus with regards to HSR funding. It would be in their best interest to try to prove HSR supporters wrong.

    It wouldn’t take much in the way of ROW investment, as the current ROW owner has already significantly rerouted traffic to give the Capitol Corridor more capacity. Furthermore, they already have quite a bit of proven demand (even given their crappy speeds) which lowers investment risk quite a bit. And electrification and construction would be comparably cheap given the much more forgiving terrain.

  2. orulz

    My preference is for all trains bound for SF to travel through Altamont and then curve south through San Jose. I suspect I may be the only person who prefers this routing. Reasons: 1. It avoids a likely complicated Dumbarton tunnel or bridge, as well as the complicated Pacheo crossing, thereby possibly costing less than any other of any of the alternatives, 2. It serves San Jose and the south bay directly, which (like it or not) is a major population center, thereby carrying a lot of political weight. This comes at the expense of a moderate detour, but remember that the nice thing about Very Fast Trains is that they can make a moderate detour and not add a ridiculous amount of time onto the schedule.

    The achilles heel is that it encounters a double dose of NIMBY (PAMPA and Livermore/Pleasanton), and it would be difficult to meet the 2h40m LA-SFservice requirement (would probably result in 2h50m service instead – but IMO if the express trains are less than 3 hours, that should be “good enough.”)

    • Beta Magellan

      Dumbarton isn’t that complicated—there’s an aqueduct being tunneled under Dumbarton, so the geology’s well known.

      Also, Altamont still does serve San Jose directly—the whole “we’re not on the mainline” thing struck me as petty insecurity more than anything else (and shouldn’t being a terminus be better for the ego?). I can kind of understand how being on a separate branch would make them antsy about being cut from phase 1, but much larger population centers (like San Diego) were also left out, and the additional cost of making a San Jose connection’s comparatively small; if San Jose does get postponed but HSR construction continues to move forward, it’s hard to imagine a situation where they don’t get connected as part of a phase 1.5 or so.

      • jim

        My assumption (though I’m watching this from 3000 miles away and may be missing nuances) is that San Jose’s fear was not being connected to HSR at all. That the branch to SJ would be in the plans and the engineering drawings, but when construction money turned out to be tight, the mainline to SF would be built and the branch to SJ wouldn’t.

        It’s easy to imagine that SJ, once left out of Phase 1, falls further behind as the claims of Sacramento become harder to ignore. With Altamont the chosen alignment, adding a wye and a branch into Sacramento is surely cheaper than building the SJ branch. A branch into Sacramento would attract SF-Sac and LA-Sac ridership. And it’d be more important (from a statewide perspective) to replace the Capitol Corridor than Caltrain.

        San Jose’s paranoia is not misplaced.

        That doesn’t mean that Altamont isn’t still the superior alignment, but it does mean that SJ politicians will fight like hell to keep Pacheco.

        • Alon Levy

          Yes, pretty much. But another lurking problem is BART. SJ really wants BART, in a subway, due to an inferiority complex. BART to SJ not only competes with HSR for ROW space (though it’s possible to accommodate both on parallel alignments) but also raises questions about why there need to be two separate lines from Fremont to SJ. For the same reason, the BART power brokers favor Pacheco: it makes it less likely that anyone will decide BART to SJ isn’t worth it. Altamont-through-Dumbarton works best with a BART extension to Livermore, but the SJ is a bigger extension than Livermore, and plays to the ring-the-Bay dream.

        • BruceMcF

          And with completion of the SF/LA segment counting as the first stage, that also opens up the door to the San Diego leg. With the secondary HSR terminus pushed that far into the future, that drives connections from San Jose to the all services station on the mainline, and San Jose becomes effectively a suburb of Fremont.

          The project viability bottleneck is the first stage, and with respect to the first stage, the differences between Pacheco and Altamont are a second order affair.

          While it simplifies the mental model to say, “Capital Corridor is UP, can’t be upgraded to 110mph”, there’s lots of time to work on that issue within the time scale of completing the first stage and then starting work on the Sacramento extension of the CV corridor in stage 2.

        • anonymouse

          From somewhat closer, I can tell you that San Jose has a huge inferiority complex and most local transportation politics centers around that. They’re jealous that even though they’re in the Bay Area’s biggest city (1 million to SF’s 800k), nobody knows or cares about San Jose as a city, and thinks of it as a giant and entirely not noteworthy valley of sprawl (which is exactly what it is). Specifically, the reason the city wants BART so badly is that it will give them a downtown subway, which will finally make it like a real Big City. That and, as I mentioned below, Board Member Rod Diridon probably had some desire to make Rod Diridon Station a fitting monument to Rod Diridon, so that the people of the big city of San Jose will remember his role in making their city so great.

      • Nathanael

        Dumbarton tunnel is expensive enough that you should build a Transbay Tube instead, and a new Dumbarton bridge has serious environmental issues. Dumbarton is “fatally flawed” in EIR terminology.

        • Alon Levy

          The alternative, a Dumbarton tunnel, would be surprisingly cheap relative to its length, because of the water tunnel. Though, bear in mind the difference between base Altamont and the second tube according to the EIR is $200 million, which is less than the inherent uncertainty in these estimates. If I didn’t know about the pecking order in the Bay Area, I would’ve guessed it’s all a ploy by Caltrain to get someone else to cover its electrification costs.

          • Plausible deniability of off-the-record sources

            A Dumbarton rail tunnel could be excavated for on the order of a billion dollars.
            Source: people actually involved in boring an actual safety-critical Dumbarton tunnel as we speak.

            Of note from the same source: it’s bore surface area (lining costs) rather than bore volume (spoil disposal costs) that dominate. Big enough for trains doesn’t mean scaling costs by the square of the diameter, as some believe.

          • Beta Magellan

            Alon, I just looked through the EIR and I think the difference is larger than that—it looks like Altamont to SF only via Dumbarton is $11 billion with 93.9 million passengers by 2030 (p. 928), but via Transbay 2 is $12.9 billion with 95.9 million passengers—it’s almost a two billion dollar difference, for only two million more passengers.

            So, it looks like even though the Transbay options had more passengers, they’d still have higher costs per mile.

  3. Beta Magellan

    Even though I’m entering into flight-of-fancy mode here, if there were to be some kind of reconsideration leading to a second transbay tube wouldn’t skyscraper foundations and the Transbay train box basically force HSR to terminate someplace else in downtown San Francisco?

    • Alon Levy

      My understanding is that it would. The through-service option was eliminated years ago by skyscraper construction. Another option, with Transbay a terminal but trains still entering from the East Bay, like this, may or may not still be possible; I’m not sure. Frankly, if there’s a second tube, there are almost certainly better sites for a station than Transbay. Even 4th and Townsend would do in a crunch, though obviously it’s away from downtown; it’s a potential Shin-Osaka, when something at the same distance from downtown of the legacy Osaka Station is still feasible.

      • BruceMcF

        The through service Oakland/SF/SJ in general was eliminated years ago, or the through service option via Transbay TC?

        • Alon Levy

          I don’t think such service is at all on the table now, but what’s been made impossible by new skyscraper construction is the Transbay through-running option.

  4. Nathanael

    Really, really, REALLY should have bit the bullet and built the second Transbay Tube. Huge payoff.

  5. anonymouse

    Don’t forget that at the time the decision was being made, HSR board member Rod Diridon was probably hoping that the main line would go through San Jose’s Rod Diridon Station, and having it arranged that way would allow Rod Diridon to have the HSRA spend money making Rod Diridon Station a fitting monument to the greatness of Rod Diridon, son of an Italian railroad brakeman and father of modern transit in Silicon Valley.

    Also, while the Capitol Corridor does indeed run on UP tracks, they seem to have a better relationship with UP than just about any other passenger service in the country (how’d they get 16 round trips a day past UP?), so improvements in speed are not out of the question, though 90 minutes OKJ-SAC and 45 minutes OKJ-SJC are probably the upper limit of that. And the HSR alternative via Pacheco is 3 times longer, so the trains have to go 3 times faster, using about 9 times more energy, which is hardly what I’d consider efficient.

    • Nikko P

      Between this and your BART comment yesterday, it seems like your ideas are bordering conspiracy theory territory.

      • Alon Levy

        I don’t think it’s conspiratorial that San Jose lobbied hard for Pacheco, and that many of the defenders online are explicitly arguing that the biggest city in the Bay Area by population shouldn’t be just on a branch.

        P.S. You asked for it a few days ago, and finally I created new categories for the FRA and Amtrak.

      • anonymouse

        I don’t think it’s a conspiracy to point out that someone is potentially steering billions of dollars of funding toward improvements to a facility named after himself. I think the “San Jose inferiority complex” part is considerably harder to prove and much closer to “conspiracy theory” territory. But it’s kind of hard to come up with any other explanation for the singleminded obsession with BART that some local civic boosters have, to the point where they inject pro-BART advocacy into everything. A couple years ago I went to a forum on bicycle safety in Santa Clara County, and they had Carl Guardino have a small Q&A, and of course he chose to mostly answer the questions about BART, which was just way off topic regardless of what I or he may think of that project. Also, I heard that the VTA actually went as far as ordering locomotives for an East Bay-San Jose commuter rail service back in 1998 or so, which means that we could have had a rail link to the East Bay for over a decade now. Unfortunately, the focus shifted to BART and the locomotives went to Metrolink instead, and rail service was delayed by 20 years.

  6. JJJ

    “Altamont is superior because of its advantage for travel from the Bay Area to Sacramento and the Upper Central Valley”


    “Pacheco is superior because of its advantage for travel from the Bay Area to San Jose and the middle Central Valley AND the coast”

    You seem to ignore the size of Fresno. The city itself (not metro) is bigger then Sacramento, but they key is that it is growing so much faster.

    By 2020, Fresno-San Jose-SF will be a huge draw for the train.

    Merced, Modesto? They’ve got nothing on Fresno.

    Mind you, my ideal situation would be to have all the options (including the bay tunnel) built. One can dream.

    • Alon Levy

      The metro area of Sacramento is more than twice the size of Fresno’s – and is actually growing a hair faster (link). And the Central Valley metros with the strongest commute ties to the Bay Area are, in descending order, Stockton, Modesto, and Merced.

      • JJJ

        “And the Central Valley metros with the strongest commute ties to the Bay Area are, in descending order, Stockton, Modesto, and Merced.”

        Right, today. Because nobody wants to commute 3 hours from Fresno.

        But when HSR comes in, it’s a whole different matter.

        Say what you want about Fresno, but Stockton is much less attractive for bay area commuters.

        • Alon Levy

          I doubt anyone wants to commute 1.5-2 hours from Stockton today, either. It’s just that some people have to drive that far until they qualify.

          • anonymouse

            And people do that because the Bay Area is so full of NIMBYs who want to be the last people to have moved to their suburbs. Nobody should be commuting by HSR: it’s terrible for the environment, and I suspect considerably more people want to live in the nice, temperate Bay Area than in the hot and smoggy Central Valley. Do we really want to subsidize the NIMBYs’ wishes? Do we really want to build infrastructure for people to burn piles of energy to commute hundreds of miles from a place where they need to burn piles of energy to air condition their house? And it gets even more absurd if you do SF-Sac via Gilroy.

          • upnorth71

            Yes, but people have no choice in the matter- they are forced to live in the valley. I had a 50K/year salary but couldn’t even afford to rent on the peninsula. Would you rather have them drive than take the train?

          • EngineerScotty

            It would be nice if someone could convince a few Silicon Valley high-techs that their parking lots would be worth more as apartment buildings. (Plus, SV companies love to encourage employees to work long hours anyway… onsite housing might be one way to go).

    • BruceMcF

      But Fresno is not substantially different either way ~ connection to Caltrain at Redwood would give it about the same accessibility to Silicon Valley either way, its much the same to San Francisco, and both the center of San Jose and the further eastern parts of the East Bay are more origins than destinations. Since its not an appreciable net plus or minus for either option, its can be quite important for the system and yet not be very important at all in the alignment choice.

  7. Pingback: High-Speed Rail in California is Worrying Itself to Death | Streetsblog Capitol Hill

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