This is the second part of my series about the Regional Plan Association event about expanding capacity at Penn Station. Much of the presentation, at least in its first half, betrays wanton ignorance, with which area power brokers derive their belief that it is necessary to dig up an entire block south of Penn Station to add more station tracks, at a cost of $16.7 billion; one railroad source called the people insisting on Penn Expansion “hostage takers.” The first part covered casual ignorance about the history of commuter rail through-running in Europe, including cities that appear in the presentation. This part goes over the core claim made in the presentation regarding how fast trains can enter and exit Penn Station. More broadly, it goes over a core claim made in the source the presentation uses to derive its conclusion, a yet-unreleased consultant report detailing just how much space each train needs at Penn Station, getting it wrong by a factor of 5-10.
The issue is about the minimum time a train needs to berth at a station, called the dwell time. Dwell times vary by train type, service type, and peak traffic. Subways and nearly all commuter trains can keep to a dwell time of 30 seconds, with very few exceptions. City center stations like Penn Station are these exceptions; the RER and the Zurich S-Bahn both struggle with city center dwell times. The Berlin S-Bahn does not, but this is an artifact of Berlin’s atypically platykurtic job density, which isn’t reproducible in any American city. That said, even with very high turnover of passengers at central train stations, the dwell time is still usually measured in tens of seconds, and not minutes. In the limiting case, an American commuter train should be able to dump its entire load of passengers at one station in around two minutes.
The common belief among New York-area railroads is that Penn Station requires very long dwell times. This is not made explicit in the presentation; Foster Nichols’ otherwise sober part of the presentation alludes to “varying dwell times” on pp. 23 and 26, but documents produced by the railroads about their own perceived needs go back years and state precise times; for through-running, it was agreed that the dwell times would be set at 12 minutes in the Tri-Venture Council comprising Amtrak, the LIRR, and New Jersey Transit. The consultant report I reference below even thinks it takes 16 minutes. In truth, the number is closer to 2-3 minutes, and investments that would precede Penn Expansion, like Penn Reconstruction, would be guaranteed to reduce it below 2 minutes.
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