Quick Note: The Importance of Penn Station Access West to Through-Running

"The issue is that without the realignment, too many trains would be going into Grand Central - all preexisting Metro-North service minus trains diverted to Penn Station Access. We expect all this through-running infrastructure to add to peak demand substantially. Today it fills about 50 peak trains per hour, which a four-track trunk line would struggle with (Metro-North runs trains three-and-one at the peak)."

"The Empire Connection exists and the tunnel has room for two tracks; it needs a short realignment to reach the right part of Penn Station - the high-numbered northern tracks as in the image, where today there is a single-track link from the Connection proper to the low-numbered tracks - but that realignment is much cheaper than a full through-tunnel such as between Penn Station and Grand Central or the various lines to Lower Manhattan mooted for longer-term plans."

"A video by the Joint Transit Association talks at length about through-running in New York - which lines are easier and which are harder, what some of the tradeoffs are, what sequencing works best with ongoing infrastructure plans starting with the Gateway tunnel. It's a good video and I recommend watching - and not just because it gets a lot of its ideas from ETA reports but also because of its own analysis and own points (about, for example, Mott Haven Junction)"

Through-running plans without Penn Station Access West would route too many trains into Grand Central, creating a peak capacity shortfall. Current peak demand fills about 50 trains per hour, which a four-track trunk would struggle to handle given Metro-North's three-and-one peak pattern. Diverting 6–10 trains to Penn Station Access alone would not prevent saturation. A Penn Station Access West realignment of the Empire Connection could shift Hudson Line trains into Penn Station northern tracks, adding capacity cheaply. The Empire Connection tunnel can accommodate two tracks and requires only a short realignment. A minimum ten-minute frequency to each terminal is advised to serve inner stations.

Read at Pedestrian Observations