• Swampoodle connection

  • Discussion relating to Southeastern Pennsylvania Transportation Authority (Philadelphia Metro Area). Official web site can be found here: www.septa.com. Also including discussion related to the PATCO Speedline rapid transit operated by Delaware River Port Authority. Official web site can be found here: http://www.ridepatco.org/.
Discussion relating to Southeastern Pennsylvania Transportation Authority (Philadelphia Metro Area). Official web site can be found here: www.septa.com. Also including discussion related to the PATCO Speedline rapid transit operated by Delaware River Port Authority. Official web site can be found here: http://www.ridepatco.org/.

Moderator: AlexC

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  by Bill R.
 
Clearfield wrote:
Any new estimate "should" be balanced against the cost to replace the old PRR bridge.
And a long term cost/benefit analysis (i.e operating budget reduction) of removing CHW from Amtrak.
  by amtrakowitz
 
Matthew Mitchell wrote:
#5 - Dyre Ave wrote:By the way, you don't even have to install third rail on a BSL-to-CHE extension, something you mentioned in a previous post. They can use subway cars capable of running on third rail and catenary (if a project like this is ever green-lighted, it'll be time to replace the current BSL cars by that time anyway). Boston already does this on its Blue Line and has for decades.
You greatly underestimate the technical challenges of such a conversion.

If you leave the current AC power system up, you need a fleet of subway cars with both AC and DC power capabilities. I don't know if they even exist (hard enough to do with main line railway trains). The AC part is particularly tough because it's high-voltage and needs more insulating as well as needing a big main transformer. If you decide to try and use the existing wires to deliver 600 VDC, you first have to make sure the wires are big enough to carry the higher currents needed (Ohm's law), you need at least a couple of new substations, and you probably need to modify the signal system to get along nicely with DC return currents.
Boston's Blue Line is a false comparison anyhow. Both third rail and overhead wires are DC. Not to mention, that system should perhaps be overhead wire over its whole length (its tunnels are former streetcar tunnels); IINM, the third rail was in place to allow interchange (formerly) between Blue and Red Lines.

I don't see the difference when it comes to return current at track level. Both AC and DC traction motors operate along the same tracks. Current from AC catenary wire is rectified to DC in the locomotive transformer anyhow, and then if the traction motors are AC, the current from there is inverted from DC to AC. Even the NYC subway has trains that have both DC and AC traction motors running from the DC third rail.

Incidentally, the third rail that Metro-North uses, apart from being under-running, is energized at the same voltage as the NYC subway (and LIRR), and the EMUs that run along the New Haven Line use both that and 12kV 60Hz AC overhead wires, as did former New Haven RR EMUs and electric locomotives when its system was 11kV 25Hz. So that system could be adapted for other uses, although the clearance of the Broad Street Subway may be prohibitive. Besides, I don't personally recommend it; perhaps the former R8 should be reconfigured to run from one "side" of CHW to the other, at a fare level and service frequency more in line with that of the subway system of Philly, and send the former R7 to Fox Chase?
  by Bill R.
 
amtrakowitz wrote: I don't see the difference when it comes to return current at track level. Both AC and DC traction motors operate along the same tracks. Current from AC catenary wire is rectified to DC in the locomotive transformer anyhow, and then if the traction motors are AC, the current from there is inverted from DC to AC. Even the NYC subway has trains that have both DC and AC traction motors running from the DC third rail.
Yes, but the rectifiers, imverters and traction motors are isolated subsystems within the envelope of the rail vehicle. While I won't go into the fundamentals of electrical theory, suffice it to say that, in the real environments of field operations, power crosses and sneak currents occur. Equipment design and the implementation of electrical system isolation must take into account the possibility of such a circumstance. And (even with precautions) when thing fail, as it did at Harold Interlocking in Queens a few years ago, it'll blow up everything.
perhaps the former R8 should be reconfigured to run from one "side" of CHW to the other, at a fare level and service frequency more in line with that of the subway system of Philly, and send the former R7 to Fox Chase?
This idea has been advanced in other threads over the years. Some have even suggested making such a service into the prototype for London Overground or S-Bahn style operations on RRD. While greater frequency might be a good thing, the other elements necessary to replicate Overground service standards represent money better spent elsewhere within SEPTA.
  by #5 - Dyre Ave
 
Bill R. wrote:
perhaps the former R8 should be reconfigured to run from one "side" of CHW to the other, at a fare level and service frequency more in line with that of the subway system of Philly, and send the former R7 to Fox Chase?
This idea has been advanced in other threads over the years. Some have even suggested making such a service into the prototype for London Overground or S-Bahn style operations on RRD. While greater frequency might be a good thing, the other elements necessary to replicate Overground service standards represent money better spent elsewhere within SEPTA.
I think it's a very good idea, especially given that the general consensus here seems to be ridership on the Chestnut Hill Lines doesn't warrant converting one of them to subway operation or building the Swampoodle Connection for the other one. But to run trains from CHE to CHW and back via the Center City Tunnel would require not building Swampoodle. I'm guessing both lines can be shown in brown (now that the Media and Sharon Hill trolleys are shown in green) since "chestnut" is a shade of brown and it was the former R8 color. As for the London Overground comparison, isn't SEPTA already considering implementing some of its aspects like high platforms and turnstiles system-wide? Free transfers to the subways and bus transfers should be $1.00, in line with CTD transfer policies. If trains ran on 10- to 20-minute intervals, depending on the time of day, that ought to put more people on the trains.
Last edited by #5 - Dyre Ave on Mon Oct 17, 2011 11:43 am, edited 1 time in total.
  by Suburban Station
 
Patrick Boylan wrote: I'm not sure increasing weekend service i's a good example of an advantage to gain from the Swampoodle connection. Isn't there enough capacity on weekends to increase service without any infrastructure investment?

I'm willing to bet many of the Chestnut Hill east and west passengers are a lot like the majority of regional rail riders, that is they probably won't consider taking a bus to the train, but would either forego the trip or drive the whole way instead.
absolutely, there is excess capacity on weekends even now, and certainly if it were tied into the subway, frequent service wouldn't be an issue. if there are capacity constraints, it's at rush hour on regional rail. not sure where you're going to the second thought.
Bill R wrote: And a long term cost/benefit analysis (i.e operating budget reduction) of removing CHW from Amtrak.
not to mention the lower operating costs of a subway train which is much lighter and requires less labor.

I'm not sure that the ridership isn't there, remember, it serves germantown, which is a pretty sizable market. there are many slow buses running down to erie and other places where traffic could be diverted to chelten via walking or the K bus
  by penncenter
 
#5 - Dyre Ave wrote:But to run trains from CHE to CHW and back via the Center City Tunnel would require not building Swampoodle.

Running the CHE into the tunnel via its Reading approach (as it does now), when you exit the tunnel, as a CHW train, you would be using PRR track, and thus, the NEC. Having a Swampoodle connection is irrelevant in this exercise. Connector would be used to allow trains using the Reading main to cross onto CHW (PRR) tracks via Swampoodle connector. Service then continues to every CHW station except N. Phila. If I understand what you are suggesting, that can be done right now, Septa has just not chosen to link those lines end-to-end.

The idea of the connector is to get the CHW off the NEC/PRR tracks. Seems like the wait times on the NEC for passing Amtrak and NJT trains are getting unacceptably (to some) long, the usage fee to Amtrak continues ad finitum, and the bridge right off the CHW branch over the Reading main needs to be replaced. The quesiton is, whether the time is right to make this service change/capital outlay. Certainly the CHW service changes, as the approach would be ME, SS, 30th as opposed to 30th SS, ME.
  by #5 - Dyre Ave
 
penncenter wrote: Running the CHE into the tunnel via its Reading approach (as it does now), when you exit the tunnel, as a CHW train, you would be using PRR track, and thus, the NEC. Having a Swampoodle connection is irrelevant in this exercise. Connector would be used to allow trains using the Reading main to cross onto CHW (PRR) tracks via Swampoodle connector. Service then continues to every CHW station except N. Phila. If I understand what you are suggesting, that can be done right now, Septa has just not chosen to link those lines end-to-end.
That's right. If SEPTA can determine that CHW trains being held by Amtrak at North Philly doesn't ruin the line's schedule that much, if they determine that Swampoodle is not worth the cost, then through-routing CHW with CHE might be worth doing. And giving the joined routes more frequent service and generous transfer privileges to SEPTA buses, subways and trolleys not currently offered on the RRD might put more people on the trains.
  by neroden
 
The key numbers necessary for determining what a sensible plan is, on a system like SEPTAs, are the branch ridership numbers.

I'm having trouble finding these on SEPTA's website....
  by Matthew Mitchell
 
neroden wrote:The key numbers necessary for determining what a sensible plan is, on a system like SEPTAs, are the branch ridership numbers.

I'm having trouble finding these on SEPTA's website....
Get the disc with the RRD Rider Census. It's got what you want.
  by Franklin Gowen
 
Matthew Mitchell wrote:
neroden wrote:The key numbers necessary for determining what a sensible plan is, on a system like SEPTAs, are the branch ridership numbers.

I'm having trouble finding these on SEPTA's website....
Get the disc with the RRD Rider Census. It's got what you want.
Disc? I'm intrigued; please clarify.
  by Matthew Mitchell
 
A CD-ROM which was and may still be on sale at the SEPTA store at 1234. Contains the complete dataset from the 2009 RRD rider census. Starts with the raw counts of boards and leaves per-station and per-train on each line, aggregates them into per-station totals, and then breaks out subtotals by county, zone, and other category. Also includes the historic boardings file going back to about 1980.

Very handy--I refer to my copy frequently.
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