Caltrain, Transbay to study capacity issues in Transbay terminal

At last week’s Friends of Caltrain panel on opportunities for level boarding and platform height compatibility between Caltrain and High Speed Rail, Marian Lee of Caltrain and Brian Dykes of Transbay said that they were working together on studying  capacity issues at Transbay Terminal.   Transbay is expected to be one of the constraints to the capacity of the blended system, where Caltrain and High Speed rail share facilities.

On the panel, Dykes said that he believes that compatible platform heights would likely help Caltrain and High Speed Rail provide more service into Transbay.   He also stated that dwell time, and the amount of time it takes to turn around trains, would likely affect capacity.

Caltrain’s earlier round of capacity studies modeled sending only two of Caltrain’s expected six trains per hour into Transbay.  With the pre-blended system, expecting to send 10-12 high speed trains per hour to San Francisco, the limit to Caltrain access may have been the proposed high level of High Speed Rail service.  However, with the blended system, Caltrain isn’t physically limited to two trains per hour, and will be modeling more trains.

At the event, Clem Tillier presented a slide showing that there are more jobs within walking distance Transbay than the rest of the Caltrain line combined. Caltrain will benefit substantially by sending as many trains as it physically can to Transbay.

Jobs at Transba

The results of the upcoming capacity studies will be potentially helpful for efforts to reduce the limits to capacity in Transbay.  How much would shared platforms help? How would reducing dwell time help? How much could dwell time be reduced with level boarding, and how much by turning trains efficiently at a terminal station?  Marian Lee of Caltrain did not say specifically what topics were being studied, but answers to these questions would be welcome. These answers will help Caltrain and the region’s rail supporters make the case for eliminating barriers.

Clem Tillier’s excellent analysis of the decisions needed to support level boarding and compatible platform heights are at his blog here.