19 September 2023

First Look at Electric Service

Caltrain's proposed weekday peak service
Caltrain has started to pull back the curtain on their fall 2024 service pattern, when the electric fleet will (finally!) enter service.

The peak service pattern is depicted at right from a Caltrain slide, and looks like this in a string diagram from our trusty taktulator. The overall score for this timetable is a lukewarm 115 points relative to the benchmark score of 100 for the 2011 timetable, and it requires just 14 trains to operate, not counting spares.

The Good

  • Peak frequency will remain at four trains per hour per direction until ridership recovers more. This requires a waiver from the FTA, which originally made its funding contingent on operating six trains per peak hour per direction.
  • This enables operating with all-electric service in the portion of the corridor between San Francisco and San Jose, relegating the diesel fleet to where it belongs: not under the wire.
  • Stops are restored throughout the corridor, increasing service frequencies especially in Silicon Valley where the 2004 arrival of the Baby Bullet decimated ridership at skipped stops that nevertheless have healthy numbers of nearby jobs and residents.
  • Off-peak service is a subset of peak service, making for a regular and consistent half-hour "takt" throughout the entire day. This makes the timetable easy to use and memorize.
  • The Gilroy branch is served by a cross-platform transfer in San Jose, reflecting the results of a recent survey of its customers that revealed that a one-seat ride was their lowest priority.

The Bad

  • The Baby Bullet unfortunately survives as Express A, skipping perfectly worthy stops throughout Silicon Valley and tragically breaking the potential symmetry of the timetable. Express A should just be another Express B, giving evenly spaced 15-minute service from Redwood City to San Jose. This is very low hanging fruit that improves the timetable score from 115 to 118 points. The Baby Bullet pattern was a great idea for speeding up diesel runs, but in the new electric age, Caltrain should let it slip into history.
  • The "South County Connector" remains as diesel rail service. There is an opportunity for  enormous savings (and better service quality for riders) from selling off the entire diesel fleet and operating the Gilroy branch with much more frequent luxury buses. Operating and maintaining an excessively large electric + diesel fleet and wasting capital funds on the expensive but dubious idea of a BEMU distracts Caltrain from its core mission. If one believes in the idea of a fiscal cliff, then it's obvious that rubber tires can help Caltrain's balance sheet until the high-speed rail project electrifies the south county corridor.
The Implausible
  •  The proposed service pattern is built around a 75-minute all stops local trip between SF and SJ. This 75-minute figure is very impressive and would be a huge strength, if only it didn't border on the implausible. These are several issues with a 75-minute local run:
    • the trains have to accelerate very aggressively, something the equipment is admittedly capable of, but ouch, that electricity bill! Operating cost will depend not just on usage but also peak load, and high acceleration makes the peaks worse.
    • the timetable padding has to be shaved down significantly from today's comfortable margins
    • the station dwell time has to come down to a crisp BART-like duration of just 30 seconds. Without level boarding, this is unlikely to work reliably in daily service. The boarding step arrangement, door spacing and interior circulation of the new EMUs is identical to the Bombardier diesel sets, so it's hard to believe they would board any faster, before even considering the possibility of a crew interventions for wheelchair users.
    • There is nothing physically preventing a 75-minute trip, but if Caltrain can pull that off, what secret sauce of brief dwells have they been holding back from us all these years? Based on past operating practice, a more reasonable expectation would be an 86-minute trip. Let this serve as a prediction that Caltrain will find out the hard way that it really does have an urgent need for level boarding.

Taken together, there's a lot to like in this emerging service pattern, and a few tweaks can make it even more optimal. With freeway traffic getting steadily worse, the new service product will sell itself.

02 September 2023

Level Boarding: Still Not Getting It

The good news: Caltrain has initiated a small study effort to develop a level boarding roadmap, as part of its portfolio of capital projects.

The bad news: in the summary of this study, Caltrain shows no sign of grasping the purpose of level boarding. We might need to display it on a freeway billboard, like this:

Caltrain does a very nice job of explaining the benefits of electrification. Faster acceleration leads to shorter trip times, a strong message that they hammer often. On level boarding, however, the messaging is muddled. It's something-something about steps? Easier and more inclusive access?


It's about shorter trip times, just like electrification. While electrification saves time in motion, level boarding saves time at rest. The savings are big: cutting station dwell time from 45 seconds (typical for Caltrain today) to 30 seconds (typical for BART, which has level boarding) is worth almost as much "acceleration" as electrification. Electrifying without level boarding is half-baked, and Caltrain should be spending a lot more on level boarding than distractions like BEMUs. Please return to your core mission to quickly and efficiently get people where they are going.

About these numbers: the diesel trip time is for an all-stops local with 45 second station dwells and 15% padding. The EMU trip time has the same dwell and padding assumptions. The level boarding time assumes that station dwells drop to 30 seconds, and padding is cut down to 10%. The lower padding is appropriate because level boarding not only makes dwells shorter, but it makes dwells much more consistent and predictable, as discussed previously. If two wheelchair users need to board, it takes the same 30 seconds, not five minutes of staff assistance. Here are the detailed stop-by-stop stats and string diagrams if you want to tinker with assumptions.