Green Line Extension to Medford & Union Sq

A Grand Junction Line semi-crazy transit pitch:

Lechmere

Twin City Plaza -- (this feels like it's too close but I can imagine an Assembly-fication of this area in the medium/long term)

Cambridge Street

Binney Street [north of Broadway] (I thought about Binney St - Kendall Square but I like the idea of deconflicting station names, especially where there's no actually interchange)

MIT [@Vassar & Mass] (I propose changing the Red Line stop to just Kendall)

Cambridgeport [between Waverly St and Mem Dr]

Not sure how it ends:

Geometry is difficult at the south end of the BU bridge, doesn't seem like it'd be possible to link up at BU West But I do like the idea of a ring or a link instead of another spoke.

Also don't see how to hit the red line at Kendall.

Just musing here, I'm sure someone has thought this one through much more thoroughly. Also does anyone know what the lines on the real GLX are going to be called? Have the BCD or E been selected to run along either branch?
 
It will be the D and E but I don't remember which line goes to which northern terminal.
 
It will be the D and E but I don't remember which line goes to which northern terminal.

Unless it has changed over the past 8 years, I was last told it is:

D to College Ave
E to Union Sq

(since D is the most reliable overall and E already goes to Lechmere so it's only one more stop)
 
Probably because no one at the MBTA seriously thinks a Porter extension is a good idea. Even I'm not convinced and all I do is come up with crazy ideas for subway extensions.

The Red Line @ Kendall & Harvard is going to need some capacity relief & some way to accommodate the now burgeoning Central-Kendall-Lechmere tech boom, both the current crush and all the development underway (like the HUGE redevelopment of the Volpe site)

I'd hope that Cambridge takes some of the real estate $ and starts looking at tax-increment financing (TIF) of transit upgrades.

Regional Rail (electrification of the Fitchburg Line from Waltham/128/20/Brandeis, through Beaver Brook, Waverly, Belmont, & indward) would be the faster, cheaper, better way of delivering, say 15 or 20 minute headways for most of the day. It'd be natural for Regional Rail to add a stop at Alewife and probably sufficient to do Alewife-Porter-Union-North Station.

Regional Rail is also the solution for West Medford (and Arlington Center) that's walkable from the CR stop there (and that won't be getting GLX), which might obviate the need to bring the GLX out to Mystic Valley Parkway (and spend the $ instead in grade-separating the Lowell Line from Rt 60/High St)

But, if it doesn't look like we come to our senses and start electrifying the CR and doing level boarding and frequent service, there's no doubt that Somerville and Cambridge covet a beyond-Union that goes:
  • Union
  • California St
  • Porter Sq
  • Sherman St
  • Alewife Superstation (CR & GLX under a pedestrian overpass)
  • Brighton St
This is basically why they forced the Union St branch to be grafted onto what had only been a straight-shot "Green Line to Medford Hillside" in the CLF/Big Dig settlement.

Having gotten the branching, the extension would be "linear" (at least one more stop to California St). If they were willing to forego any "easy" future extension, they'd probably be able to do a GLX terminus in a (widened) cut at Porter without actually passing under Mass Ave or blowing up too much of the station, not unlike stub-ending Blue @ MGH where "where we go from here" is for the folks of the 22nd Century.
 
The Red Line @ Kendall & Harvard is going to need some capacity relief & some way to accommodate the now burgeoning Central-Kendall-Lechmere tech boom, both the current crush and all the development underway (like the HUGE redevelopment of the Volpe site)

I'd hope that Cambridge takes some of the real estate $ and starts looking at tax-increment financing (TIF) of transit upgrades.

Regional Rail (electrification of the Fitchburg Line from Waltham/128/20/Brandeis, through Beaver Brook, Waverly, Belmont, & indward) would be the faster, cheaper, better way of delivering, say 15 or 20 minute headways for most of the day. It'd be natural for Regional Rail to add a stop at Alewife and probably sufficient to do Alewife-Porter-Union-North Station.

Regional Rail is also the solution for West Medford (and Arlington Center) that's walkable from the CR stop there (and that won't be getting GLX), which might obviate the need to bring the GLX out to Mystic Valley Parkway (and spend the $ instead in grade-separating the Lowell Line from Rt 60/High St)

But, if it doesn't look like we come to our senses and start electrifying the CR and doing level boarding and frequent service, there's no doubt that Somerville and Cambridge covet a beyond-Union that goes:
  • Union
  • California St
  • Porter Sq
  • Sherman St
  • Alewife Superstation (CR & GLX under a pedestrian overpass)
  • Brighton St
This is basically why they forced the Union St branch to be grafted onto what had only been a straight-shot "Green Line to Medford Hillside" in the CLF/Big Dig settlement.

Having gotten the branching, the extension would be "linear" (at least one more stop to California St). If they were willing to forego any "easy" future extension, they'd probably be able to do a GLX terminus in a (widened) cut at Porter without actually passing under Mass Ave or blowing up too much of the station, not unlike stub-ending Blue @ MGH where "where we go from here" is for the folks of the 22nd Century.

This has been discussed here previously, but I'd rather see a GLX past Porter turn south behind the Fresh Pond movie theater and head along that ROW towards Watertown Square. What's the benefit of GLX and CR at Alewife if they're also both at Porter meeting the Red Line just two stops away?

Extending the GL beyond Union to somewhere in the Dane St/Park St/Sacramento St area seems relatively straightforward.

At Porter you'd probably be best to dig down the CR trench a couple stories one direction at a time (with Fitchburg trains in both directions using the remaining side), lay down a GLX level, then stack the CR on top of it. While you're at it dig down deep enough to make Porter CR 100% level boarding, and recoup a fraction of the cost by selling street level air rights along Somerville Ave. Ideally the Porter GL platform could be accessed from the existing Porter Red Line fare gate level.
 
A Grand Junction Line semi-crazy transit pitch:

Lechmere

Twin City Plaza -- (this feels like it's too close but I can imagine an Assembly-fication of this area in the medium/long term)

Cambridge Street

Binney Street [north of Broadway] (I thought about Binney St - Kendall Square but I like the idea of deconflicting station names, especially where there's no actually interchange)

MIT [@Vassar & Mass] (I propose changing the Red Line stop to just Kendall)

Cambridgeport [between Waverly St and Mem Dr]

Not sure how it ends:

Geometry is difficult at the south end of the BU bridge, doesn't seem like it'd be possible to link up at BU West But I do like the idea of a ring or a link instead of another spoke.

Also don't see how to hit the red line at Kendall.

Just musing here, I'm sure someone has thought this one through much more thoroughly. Also does anyone know what the lines on the real GLX are going to be called? Have the BCD or E been selected to run along either branch?

Not bad, but I think that a placeholder for a train station, including double track width, was already built in to the base of MIT's Brain & Cognitive Sciences building on Mass ave, here.

I would think your Binney St. & Mass/Vassar stops would get merged into this location.
 
With GJ, I was envisioning more of something with Indigo and the Worcester line. Not sure how you would get to Green from GJ.

At this point it sure looks like Cambridge is doing what they can to stop GJ from being used more than what it is now though.
 
With GJ, I was envisioning more of something with Indigo and the Worcester line. Not sure how you would get to Green from GJ.

At this point it sure looks like Cambridge is doing what they can to stop GJ from being used more than what it is now though.

Grand Junction is wide enough for double tracked light rail, but not wide enough for double tracked commuter rail.

Plus going from the Green Line to Grand Junction would be easy, the GLX to Union passes by the Junction near the Twin City Plaza.

Best case scenario would be to extend the Grand Junction line to have stops at BU, the Allston Yards project, and end it at Boston Landing.
 
Even if Porter takes much longer, a one-stop extension past Union Square to Dane or Park would make a lot of sense and be very cheap. The Fitchburg Line ROW is quad-track-width the whole way, and there's plenty of commercial and residential density to make good use of the stop.
 
Best case scenario would be to extend the Grand Junction line to have stops at BU, the Allston Yards project, and end it at Boston Landing.

Ah, well if it was possible to roam on the Worcester Line tracks, then you could do that. That was kind of what I was suggesting with Indigo but having it start at Riverside. Maybe have a stop near Kendall, the BU Bridge, West Station, Boston Landing...
 
Grand Junction is wide enough for double tracked light rail, but not wide enough for double tracked commuter rail.
I know it's been discussed many times before (either here or RR.net or both), but anything that runs short headways and requires grade crossing protection (i.e. not light rail) has a lot of potential to cause issues for the 1/CT1 on Mass Ave. Grade separation gets complicated because of the swamp and Red Line below and MIT power plant/Building 46 above.

Plus going from the Green Line to Grand Junction would be easy, the GLX to Union passes by the Junction near the Twin City Plaza.

To be fair, it's on the wrong side of the Fitchburg main and vertical space for an overpass is constrained by the McGrath viaduct.

Best case scenario would be to extend the Grand Junction line to have stops at BU, the Allston Yards project, and end it at Boston Landing.

Given the case of GL-Grand Junction, agreed.
 
If commuter rail ends up being converted into Regional Rail as proposed by Transit Matters, I think you could just add a stations on the Fitchburg Line at Union Square in Somerville (to allow transfer with GLX) and at Alewife, along with any other in-between stations you would want. No further extension of the Green Line needed.
 
If commuter rail ends up being converted into Regional Rail as proposed by Transit Matters, I think you could just add a stations on the Fitchburg Line at Union Square in Somerville (to allow transfer with GLX) and at Alewife, along with any other in-between stations you would want. No further extension of the Green Line needed.

What's the benefit of stopping CR at Alewife under any scenario? Fitchburg already ties in to the Red in Cambridge at Porter. There is only one RL station closer to Alewife than Porter, and it is Alewife. Stopping the CR there would do more harm (by slowing the Fitchburg line) than good.

The same can be pretty much be said for a Union CR stop (Fitchburg meets GL at North Station)...
 
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What's the benefit of stopping CR at Alewife under any scenario? Fitchburg already ties in to the Red in Cambridge at Porter. There is only one RL station closer to Alewife than Porter, and it is Alewife. Stopping the CR there would do more harm (by slowing the Fitchburg line) than good.

The same can be pretty much be said for a Union CR stop (Fitchburg meets GL at North Station)...
Davis is closer to Alewife than Porter but yea, you're probably right about the existence of Porter negating the need for a similar setup at Alewife.
I think a CR stop at Union to link with the GLX would be a good idea. We're on the verge of huge development between Lechmere and Union.
 
Davis is closer to Alewife than Porter but yea, you're probably right about the existence of Porter negating the need for a similar setup at Alewife.

It isn't though; Davis is closer to Porter than to Alewife. And even if it were perfectly equidistant between the two, a morning Porter>Davis Red Line commute is easier than a morning Alewife>Davis commute (and vice-versa in the evening) because it's a "reverse commute"; there's more spare capacity on the Red in that direction.
 
It isn't though; Davis is closer to Porter than to Alewife. And even if it were perfectly equidistant between the two, a morning Porter>Davis Red Line commute is easier than a morning Alewife>Davis commute (and vice-versa in the evening) because it's a "reverse commute"; there's more spare capacity on the Red in that direction.

ah, I just picked up your post wrong and figured you'd forgotten about davis, either way, I agree with your point on Alewife but not Union.
 
It isn't though; Davis is closer to Porter than to Alewife. And even if it were perfectly equidistant between the two, a morning Porter>Davis Red Line commute is easier than a morning Alewife>Davis commute (and vice-versa in the evening) because it's a "reverse commute"; there's more spare capacity on the Red in that direction.

I think either is fine. In fact, I'd prefer a few less minutes on the CR to transfer at Alewife to get to Davis rather than going into Porter, then back out to Davis. Yes, Alewife-Davis is going with the flow of morning traffic, but Alewife is the first stop and it never fills up. Davis (my stop) is where you typically start seeing the train becoming SRO, and sometimes not even until Porter. Capacity really isn't an issue either way between these points on the Red Line. But this is really splitting hairs - the Porter stop is fine. No need to have both or re-work the CR network to make it Alewife.
 
The only arguments I could see for an Alewife CR/RR infill is to provide access to the large amount of office/lab space and new housing out there and to capacity-relieve the Red Line. However, I think regional rail frequencies would be needed to justify anything, with the idea that high-frequency service would make Waltham and Waverley much more attractive commute origins. That said, I think we may be straying from the GLX topic a bit...
 
I suppose if the transfer at Alewife could be made easier and faster than the Porter one, then it might make some sense.

The transfer at Porter is laborious. I'm a fairly fit person, but it's a lot of stairs (I counted them once but have forgotten), then more to get to the lower tracks if backwards commuting towards Alewife.

The reverse commute from red line to CR at Porter is even worse, and the platform is a joke. That needs addressing.

I do love the idea of Porter fixed of it's warts and a green line extension from the Union Sq. spur. Particularly if Union square blossoms as intended. It would be great to have commuters from multiple directions, and not needing to come through the downtown stations to get there.
 
I think it almost always makes sense to have commuter rail to subway transfer at the end of the subway line. That would also make the Alewife garage useful for people taking commuter rail, and that could take some load off the Red Line. I suppose you could eliminate the Porter CR stop, but the point of Regional Rail is to have closer-together stations. Having the station at Alewife makes a lot of sense for people who live near Alewife as well. If they're going to Union Square or North Station, they would then be able to take one train rather than two. And it would allow them to reverse commute without going in to go out.
 

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