North Station Green Line Pocket Tracks: Going Somewhere?

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North Station Green Line Pocket Tracks: Going Somewhere?

Postby Arlington » Fri Jun 22, 2012 3:39 pm

This was probably in an ancient thread when the GL from Haymarket to Science Park was closed for being put underground, but I can't find it.

The pocket tracks at North Station on the Green Line aren't just 1 pocket track (such as is ideal for simple reversals), but are 2 (which is better for their current use of storage and turn-back).

But the net result is the incline to Science Park is really configured as a full flyover--as if the lower tracks were intended to "go somewhere". Do they point somewhere? (like the West End and Charles MGH). Is the end a knockout panel or a true dead end?
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Re: North Station Green Line Pocket Tracks: Going Somewhere?

Postby BostonUrbEx » Fri Jun 22, 2012 8:49 pm

I've always wondered the same. It looks as though it is provisioned for a tunnel extension.
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Re: North Station Green Line Pocket Tracks: Going Somewhere?

Postby Disney Guy » Sat Jun 23, 2012 8:05 pm

The tail tracks go east of the existing viaduct. If the route were to be extended underground it would run into the Charles River (no point going under because the viaduct already crosses the Charles) or go under the Orange Line and curve around to Commercial St and then to Atlantic Ave (in a manner similar to the Atlantic Ave. el).
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Re: North Station Green Line Pocket Tracks: Going Somewhere?

Postby The EGE » Sat Jun 23, 2012 10:30 pm

The west end of the tail tracks have more possibility to them, since the flyover heading to the viaduct leaves them room to run under. Probably in case they wanted to do a Riverbank subway or something.
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Re: North Station Green Line Pocket Tracks: Going Somewhere?

Postby Arlington » Sat Jun 23, 2012 10:44 pm

Disney Guy wrote:The tail tracks go east of the existing viaduct. If the route were to be extended underground it would run into the Charles River (no point going under because the viaduct already crosses the Charles) or go under the Orange Line and curve around to Commercial St and then to Atlantic Ave (in a manner similar to the Atlantic Ave. el).

Disney Guy and I are not picturing the same divergence. I think UrbEx and EGE and I agree where we''re looking.

To be clear, an *inbound* journey from Science Park has these elements:
1) Incline descending to a tunnel portal
2) Running tracks diverging (spreading apart) as they get to the portal (almost wide enough for 2 tracks to be inserted between them, as viewed from above)
3) Shortly inbound from the portal, an inbound train finds that it has completed its spreading away from the outbound track and actually passed over two tail tracks (the outbound running track has just "hugged" the far wall). From the inbound side you can't quite see how far under the flyover they go and the tails appear to be diving.
4) Once the tunnel is 4 tracks wide the tail tracks "come up" and the running tracks come down to the same level (as viewed by an inbound viewer)
5) With all 4 on the same level and parallel with Causeway St, lots of switching is done.
6) Switching complete, the running tracks diverge vertically while doing a right-angle turn to serve the NS Superstation. Any inbound train turns right and goes to the lower level and the outbound tracks appear to climb because they serve the upper level of the NS Superstation. I don't call this a flyover because no tracks fly under.

So I'm focused on the flyover at the extreme outbound-most end of the tail tracks (part 3, above). Viewed in Google's 45 degree view, it situated roughly where the lone building is on the left of this map (where Lomasney Way, Auerbach Way, and Nashua St meet).

Focused on the 4-track wide part Between the viaduct-incline curve and the NS Superstation curve the ROW is flat, level and 4 tracks wide, with the

outbound running track (climbing to Science Park) on the North (farthest from Causeway St/closest to the Zakim)
outbound tail track (diving a little bit at its outbound-most end)
inbound tail track (diving a little bit at its outbound-most end)
inbound running track (descending from Science Park) on the South (passing over the two diving stub tracks)

My question is, if you extended the line of the two tail tracks from this point, are you intended to get somewhere? From the Aerials, I'd guess you're aimed at the Basketball City parking structure.
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Re: North Station Green Line Pocket Tracks: Going Somewhere?

Postby sery2831 » Sun Jun 24, 2012 1:55 am

Here is one pic of the pocket: http://sery2831.smugmug.com/Architectur ... &k=jdPsRNd

The tunnel under the Garden was built in 1993-1995 and was connected to the viaduct 2004-2005. The tunnel from the 90s may have been dug out to create a stub before the incline was built. This is just a thought.
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Re: North Station Green Line Pocket Tracks: Going Somewhere?

Postby Adams_Umass_Boston » Sun Jun 24, 2012 11:48 am

Arlington wrote: where the lone building is on the left of this map


That building has a name, it is the last Tenement of the West end.

http://en.wikipedia.org/wiki/File:Build ... Boston.jpg
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