Passenger Trains > Staff recommends standard gauge for second Transbay Tube

Major update on Bay Area's second Transbay Tube

SFGate.com
By Jerold Chinn
Nov 26, 2024

The project to build a second Bay Area Transbay Tube, known as Link21, reached a significant milestone last week when its planners introduced a staff recommendation for the first time — that the new rail crossing between Oakland and San Francisco should use standard gauge rail. https://cdn-channels-pixel.ex.co/events/0012000001fxZm9AAE?integrationType=DEFAULT&template=design%2Farticle%2Fplatypus_two_column.tpl

A standard gauge system offers critical advantages, such as enabling interoperability with other regional rail systems — like Caltrain, Capitol Corridor and Amtrak — and improving connectivity across Northern California. Standard gauge is the global rail width standard used by most transit systems worldwide, but not by BART, which has a wider, broad gauge system that is unique to it.

Camille Tsao, who serves as the program lead for Link21, shared a conceptual design Wednesday of how a standard gauge would work with metro urban rail service and intercity or express rail that tends to offer less frequent service in the Bay Area. It showed that using a standard gauge in the new rail crossing could help transit reach a larger region. Tsao added that Link21 has been doing community outreach this year and received positive responses about the benefits of using a standard gauge.

The BART chapter of SEIU 1021 was against the use of standard gauge at the BART board meeting Thursday, voicing a preference for the second tube to use BART’s rail standard. “It just makes no sense to lose this opportunity,” said John Arantes, the chapter’s president. “You’re not going to get another chance to create a third tunnel across the bay. This is it.”  He also reminded the BART board how passengers were riding trains “like sardines in a can.”

Rob Padgette, Capitol Corridor managing director, said the Link21 team will plan further development of the project now that a standard gauge has been recommended. He also said that the California State Transportation Agency and Caltrain plan to take a larger leadership role in the project.“Important to remember is that this missing link will serve far more than Capitol Corridor,” Padgette said, pointing out that it would provide a connection between regions that will allow for frequent trips.

BART spokesperson Alicia Trost said that both the BART and Capitol Corridor boards will be asked to approve the staff recommendation to advance Link21 as a standard-gauge rail project.

Trost gave no timeframe on when the boards will take up the staff recommendation.  Preliminary estimates from Link21 list the cost of the project at $29 billion, with a completion year of 2040.

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Edited 1 time(s). Last edit at 11/27/24 22:54 by GenePoon.

The long term answer is actually to reguage BART correcting the mistake made by the design consortium sixty years ago.   The myth that SF Bay Area wind required wider guage was false from the get go.  
That said, if we are to have a second transbay tube, it should be compatible with the US rail network in general.    The other mandate we need is that BART  and the new tube provide 24/7 transbay service.  

Regaging BART's track would be a monumental (and costly) effort, given its widespread use of concrete crossties. The equipment, of course, would also have to be regaged. Why not make the tunnel track dual gage? BART's 66" gage could easily incorporate a third running rail for standard gage equipment. One hitch might be the difference in crashworthiness standards between transit rolling stock and conventional rolling stock. This would likely require some sort of interlocking arrangement to maintain separation of the two types.

Yep, dual gauge is the best answer.  Several South American RRs use dual gauge concrete ties, not a techincal issue at all.   Just a bit of speical trackwork needed at both ends to bring in and out the standard gauge stuff.    Also, no clearance issues as BART is wider and stnadard gauge would be inside the clearance outline.  Maybe an issue with height if Amtrak hi level stuff is to be operated.  So, lets stop paying high priced consultants to figure out which way to go, build it dual gauge and the trains will come. 

Sounds great, but where's the money going to come from?  It won't be from the Feds anytime soon at all.  Hopefully this will all come to pass in the next 75-150 years.

Cheers,
Harry

While regauging BART is the ideal solution, I don't see it happening.  They should build a dual level tube, standard gauge on one level, BART on the other.  But I don't think there's funding for that, let alone a standard gauge tube.  I don't have the links handy, but there was a blog post or some type of article years ago talking about a dual setup option like that with a few options for connecting on each end.  For BART, the idea was to connect to just the Richmond/Pittsburg lines in Oakland and run to 16th & Mission or out Geary in San Francisco.  For standard guage, Oakland would be a connection for the Capital Corridor to Sacramento and ACE to the Altamont Pass and Stockton; while on the SF side, the idea was to connect to the CalTrain 4th St station.

Unfortuntately it's all pie in the sky until someone finds funding.

Nathan

atsf121 Wrote:
-------------------------------------------------------
> They should build a dual level tube, standard gauge
> on one level, BART on the other.

No need for dual level. As mentioned above, dual gauge should work just fine:

https://cdn.trainorders.com/attachments/fullsize/1239000/Seikan2a.jpg

That image is from my report in 2017:

https://www.trainorders.com/discussion/read.php?6,4407958

World's 2nd longest tunnel, underwater Seikan Tunnel at 33+ miles has double dual-gauge tracks in a single bore. BART's current Transbay Tube has dual bores.

If the Link21 consultants are doing their jobs, they should be analyzing the Seikan Tunnel. That mega project settled on single bore, double tracks to be cost "effective" but that has resulted in a difficult-to-solve problem they didn't quite anticipate 30+ years ago.

While the project planner smartly anticipated a possible Shinkansen extension via the Seikan Tunnel and engineered it to accomodate HSR, they didn't anticipate the technology advancements on HSR where top revenue speeds leaped from 220-240 km/h to 320 km/h. That leap started several years AFTER the tunnel was completed and started service, in the 1990s.

And the difficult-to-solve problem is how to handle the wind turbulence caused by Shinkansen meeting a non-HSR train in the single bore, and especially freight trains where the container can become dislodged inside the tunnel. There's a speed restriction on the Shinkansen in the tunnel because of this. The restriction has increased from 140 km/h to 160 km/h in 2019, 2 years after I posted the report. If there are no meets with non-HSR train inside the tunnel, the Shinkansen can run 260 km/h.

Hint: make the tunnel dual bores like the current Transbay Tube - don't be cheap.

And one more hint: venting out exhaust in a tunnel is a solvable but major problem - Moffat and Cascade Tunnels, for example. So only electrified trains (Caltrain and BART) are allowed in the "dual gauge" tunnel, no diesels should be allowed. If Link21 didn't consider this, they are NOT doing their jobs.

Seikan Tunnel had huge cost overruns, and was criticized for that and the continuing high maintenance costs, but proved itself to be worthy, connecting the economies of Honshu (the main island) and Hokkaido (northernmost island). The sleeper trains that travelled the tunnel were almost always sold out, and it became easier for the Honshu people to enjoy Hokkaido's seafood and fresh dairy products.

Lesson in all this? Like the comment I made about the Caltrain Stadler EMU's increase in weekend ridership few weeks ago, there has to be "building (economically)" to justify this project. Ridership won't magically appear just by building the 2nd Transbay Tube, so say NO to "build it and they will come."

While Link21 can continue to do studies, funding to start this mega project is only justified when transit ridership in the Bay Area has definitive and sustained increases - more buses, more trains, more crowding. False ridership increase with short term events like fluctuating fuel costs DOESN'T COUNT.

Agree with dual gage. 

What is the intended purpose of this tunnel and these tracks?  What rail system is going to operate up to 20 trains per hour on this tandard gauged track?