Green Line Extension to Medford & Union Sq

Currently, there is a Green Line train sitting just behind the Brattle Loop platform at Government Center. Earlier today, there was one all the way up on the platform itself.

PXL_20210805_011217516.jpg


If I were looking for a place to park a consist to use for testing the new Lechemere viaduct, this would be it.

Testing will also soon start on the Union Square branch as well, with another vehicle parked in the new Union Square maintainence facility/carhouse.

mass.streetsblog.org

Green Line Extension Update: Trains Arrive in Somerville

In the coming weeks, Green Line trains will venture out onto the new tracks of the Union Square branch for four months of systems integration testing to work out any remaining kinks before the new …
mass.streetsblog.org
 
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Wash said:
If I were looking for a place to park a consist to use for testing the new Lechemere viaduct, this would be it.
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I think with the Lechmere yard out of service they've probably needed to use the Brattle Loop for storage. (They also tended to store cars on it off-peak even before that, which meant it couldn't be used for revenue service, which was annoying whenever three D trains would come in one after another and turn when trying to go GC-North Station to catch a CR.)
 
FWIW, nugget in that MA StreetsBlog post: Confirmation that the community path will not open early. It will open at the earliest next May.
 
I've been reading/skimming through some thick GLX documents in preparation for expanding the Wikipedia articles about the GLX and its stations. And I mean thick: the two-part winning technical proposal is 384 and 376 pages, the technical provisions is 522, and the technical specifications is a whopping 3,495 pages. Most of it is incredibly dry and thorough (right down to specifying the length of the countertop in the kitchenette in the operator buildings at the terminals), but there are some interesting tidbits tucked in here and there.

  • The GLX is designed for 5-minute headways on each branch, with the ability to operate at 75% headways (i.e, run 3.75-minute headways) to recover from service disruptions. I really hope the actual signal system is capable of handling shorter headways when we inevitably need to add additional capacity to Medford.
  • Maximum travel time, including dwells, is 4.75 minutes Union Square–Lechmere and 14 minutes Medford/Tufts–Science Park (thus about 12 minutes to Lechmere). A 2011 ops plan indicated 4.5 minutes Union Square–Lechmere and 9 minutes Medford/Tufts–Lechmere. For comparison, Chestnut Hill–Longwood, which is the same distance (3.4 miles) and number of stops as Medford/Tufts–Lechmere, is currently scheduled for 13 minutes.

    Even if the actual running times are closer to the longer side (and not having faregates certainly won't help), it's pretty amazing how much faster this will be than current service. The 87 is currently scheduled at 7-15 minutes between Union Square and Lechmere, and the 80 at 19-21 minutes between College Avenue and Lechmere. In traffic, those times can grow substantially.

    Scheduled time from Tufts to Park Street will be about 20-22 minutes, versus 13-18 minutes on the Red Line. From anywhere north of Powder House Square, the Green Line will definitely be the better way to get anywhere downtown, especially places that require a transfer from the Red Line. Scheduled time (on a one-seat ride) will probably be about 27-30 minutes to Copley, and 40 to Longwood. That's just about parity with travel time from Davis, with the advantage of that one-seat ride. From everywhere else on the extension, GL service will blow existing bus service out of the water.
  • Maximum speed is to be 50 mph all the way from Science Park to Medford/Tufts, including over Red Bridge. That heavily implies that the Lechmere Viaduct work will result in a 50mph limit over the viaduct, which would be amazing. The Union Square Branch will also be 50 mph, except for 10 mph outbound and 20 mpg inbound over Red Bridge.
  • Minimum radius is 275 feet on the mainlines and 120 feet for the yard leads, with maximum grade of 6% - all substantially better than the existing system.
  • A section of the old steel elevated will in fact be preserved for display: " DB Entity shall implement all existing MOA, Amendment #1, and consulting party accepted commitments, measures, and designs and specifications in the Section 106 accepted design for the salvage removal, repair and preparation, and reinstallation as an interpretive object of a section of the existing historic steel Lechmere Viaduct. "
  • The relocated CR tracks are designed for 70 mph, with the alignment not to preclude a future increase to 79 mph.
  • The stations are explicitly designed for easy conversion for Type 10 LRVs: " Design shall support the vertical relocation of platforms to 14” above Top of Rail (TOR) for future level boarding with the Project and Existing System equipment. " All platforms are built at 225' but designed for future extension to 300' (except Lechmere, which is being built at 300')
  • Although the stations don't have faregates, they will all have fare vending machines.
 
The EGE said:
  • Maximum speed is to be 50 mph all the way from Science Park to Medford/Tufts, including over Red Bridge. That heavily implies that the Lechmere Viaduct work will result in a 50mph limit over the viaduct, which would be amazing. The Union Square Branch will also be 50 mph, except for 10 mph outbound and 20 mpg inbound over Red Bridge.
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So that would mean all of the Greenline cars will have to have their governors changed to 50 mph. I haven't heard anything about raising the speeds on the Riverside line but I know there has been track and signal work done there. Does anyone know anything about this? They haven't run anything at 50 mph since the Boeing LRV ran there around 40 years ago!
 
BostonTrainGuy said:
So that would mean all of the Greenline cars will have to have their governors changed to 50 mph. I haven't heard anything about raising the speeds on the Riverside line but I know there has been track and signal work done there. Does anyone know anything about this? They haven't run anything at 50 mph since the Boeing LRV ran there around 40 years ago!
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Type 7's and 8's are designed for 50, and ran up to 45 (with cheaters going faster) until the 2007 accident imposed the current 35 MPH limit. There are no speed governors installed on the fleet. An operator today could illegally rev it to 50 if they really wanted...but they'd get suspended/fired for it ASAP because the fingerprints of such an overspeed would immediately be all over the GPS train tracker. The speed restriction is scheduled to be lifted as soon as some collision avoidance system is installed and max-visibility LED signals get put in on the parts of the outer D where the NTSB flagged sun-angle visibility issues after the '07 crash. No fleet modifications will be required, because they aren't speed-limited in the first place.


EDIT: Actually, for a few years after the accident there were still enough reports of speeding operators on the D that they installed radar-gun monitoring sites for awhile to get everyone in compliance. That's how ungoverned the cars are.
 
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I forgot that the Type 8s operated at 50 during their initial appearance on the D.

I know in the past they had inspectors with speed guns who would give out some kind of punishment for speeding (suspensions I think). Not sure if that's still a practice.
 
737900er said:
I forgot that the Type 8s operated at 50 during their initial appearance on the D.

I know in the past they had inspectors with speed guns who would give out some kind of punishment for speeding (suspensions I think). Not sure if that's still a practice.
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The selective radar gun enforcement was only a bridge era to keep the NTSB at bay until they could get the continuous train tracker installed...which they did GL-wide by 2015. Today the tracking is instantaneous and precise enough that any large-degree overspeed would immediately be picked up by the tracker and trigger some alarm bells from the signature it left. Obviously that would be retroactive-only punishment (where this latest accident says nothing less than preemptive speed control will ever be good enough), but it's a pretty hard system to totally evade the way each trip is continuously logged. If you leave a ping signature on the tracker that says you oversped, the boss is gonna have a word with you at the end of your shift for sure.
 
F-Line to Dudley said:
Type 7's and 8's are designed for 50, and ran up to 45 (with cheaters going faster) until the 2007 accident imposed the current 35 MPH limit. There are no speed governors installed on the fleet. An operator today could illegally rev it to 50 if they really wanted...but they'd get suspended/fired for it ASAP because the fingerprints of such an overspeed would immediately be all over the GPS train tracker.
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Sorry but none of this is true. The current speed limit is 40 mph, not 35, and all of the cars are maxed out at 40 mph. Operators cannot exceed that speed no matter how much they wanted to.

And I believe you are talking about the fatal Ter'rese Edmonds (RIP) "micro-sleep" crash? That was in May 2008. No speed restrictions were instituted due to that incident.
 
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BostonTrainGuy said:
Sorry but none of this is true. The current speed limit is 40 mph, not 35, and all of the cars are maxed out at 40 mph. Operators cannot exceed that speed no matter how much they wanted to.

And I believe you are talking about the fatal Ter'rese Edmonds (RIP) "micro-sleep" crash? That was in May 2008. No speed restrictions were instituted due to that incident.
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When were speed governors installed on the vehicles? That has not always been the case. They were doing widely reported radar checks for overspeeds on the D as late as 10 years ago when that type of overspeeding was confirmed to be still permissible...the Type 9 spec sheet lists a vehicle MAS of 50...Type 8's have not been substantially mechanically modified at all since being accepted into service...and speed governors were not on any bucket list for the Type 7 midlife rebuilds. Are you telling us that the agency stealthily installed speed governors on the fleet at some point in the last decade...but didn't once think to trot out that factoid as a point for public confidence in the PR cleanup after any of their various news-leading collisions???


Pre-'07 I witnessed with my own eyes...on more than one occasion...a Type 7 speedometer hitting 46-47-48 on the outer D when riding in the 'prime railfan spot' as standee right next to the cabin door of the front car. Just as many people in that old linkied RR.net thread claimed they also did. That was not a misremembering. It was not an "only on the Boeings" thing; it definitely happened with the current fleet and current-construction 7-8 consists. And it was not a rare occurrence at all.
 
BostonTrainGuy said:
Operators cannot exceed that speed no matter how much they wanted to.
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In 2011 or 2012 I saw an operator who had essentially a Green Line speeding ticket on the console. It said they were going 42 in a 35 and they got a 2 day suspension. It was 10 years ago so the exact numbers might be off, but I remember it happening. They can go over 40.
 
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F-Line to Dudley said:
The selective radar gun enforcement was only a bridge era to keep the NTSB at bay until they could get the continuous train tracker installed...which they did GL-wide by 2015. Today the tracking is instantaneous and precise enough that any large-degree overspeed would immediately be picked up by the tracker and trigger some alarm bells from the signature it left. Obviously that would be retroactive-only punishment (where this latest accident says nothing less than preemptive speed control will ever be good enough), but it's a pretty hard system to totally evade the way each trip is continuously logged. If you leave a ping signature on the tracker that says you oversped, the boss is gonna have a word with you at the end of your shift for sure.
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I know this isn't really the thread to discuss this, but part of me wouldn't be surprised if the NTSB finds that management was turning a blind eye to speeding on B/C/E and more concerned about speeds on D and central subway.
 
Brattle Loop said:
I think with the Lechmere yard out of service they've probably needed to use the Brattle Loop for storage. (They also tended to store cars on it off-peak even before that, which meant it couldn't be used for revenue service, which was annoying whenever three D trains would come in one after another and turn when trying to go GC-North Station to catch a CR.)
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One of the stated reasons for the size of the new yard is to accommodate cars that were previously stored at Brattle Loop during the service day so that it can be used for short-turns with the extensions, in addition to those that were stored at Lechmere and net-new capacity.
 
737900er said:
One of the stated reasons for the size of the new yard is to accommodate cars that were previously stored at Brattle Loop during the service day so that it can be used for short-turns with the extensions, in addition to those that were stored at Lechmere and net-new capacity.
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That'd be a welcome development. I've heard elsewhere that the loop is restricted to single-car operations at the moment (at least pre-pandemic they tended to run a single Breda at near-peak times), something to do with the platform there. I don't know if that's true or just a rumor (though they did apparently screw up raising the Brattle platform in the 2014-16 renovation).
 
F-Line to Dudley said:
When were speed governors installed on the vehicles? That has not always been the case. They were doing widely reported radar checks for overspeeds on the D as late as 10 years ago when that type of overspeeding was confirmed to be still permissible...the Type 9 spec sheet lists a vehicle MAS of 50...Type 8's have not been substantially mechanically modified at all since being accepted into service...and speed governors were not on any bucket list for the Type 7 midlife rebuilds. Are you telling us that the agency stealthily installed speed governors on the fleet at some point in the last decade...but didn't once think to trot out that factoid as a point for public confidence in the PR cleanup after any of their various news-leading collisions???


Pre-'07 I witnessed with my own eyes...on more than one occasion...a Type 7 speedometer hitting 46-47-48 on the outer D when riding in the 'prime railfan spot' as standee right next to the cabin door of the front car. Just as many people in that old linkied RR.net thread claimed they also did. That was not a misremembering. It was not an "only on the Boeings" thing; it definitely happened with the current fleet and current-construction 7-8 consists. And it was not a rare occurrence at all.
Click to expand...

I can't give you an exact date but we have recently discussed that due to a hunting issue on the 7s, the Highland Branch speed was reduced from 50 to 40 mph. It was probably done at that time but I can't verify that. I will state that they are presently governed with a top speed of 40 mph and have been for many years.

Radar is still often used throughout the Greenline. It's not exclusive to the Riverside Line for overspeeding. You will even see it used in the subway often at North Station because the platform is so long but the speed limit is 10 mph for the entire length. Northeastern is also one of those (10 mph for a long block). The trail crossing in Newton in the Hammond Woods is also 10 mph. And they can get you at any station which is again 10 mph from end to end even though some platforms like Newton Highlands are really really long. You can add every road crossing on the B line too.

If the GLX is going to be 50 MPH, the D Line should follow suit if they have solved the hunting problem. I just don't know if the Highland Branch tracks are up to the task.
 
737900er said:
In 2011 or 2012 I saw an operator who had essentially a Green Line speeding ticket on the console. It said they were going 42 in a 35 and they got a 2 day suspension. It was 10 years ago so the exact numbers might be off, but I remember it happening. They can go over 40.
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I can emphatically state that an operator can put the pedal to the metal and the train will max out at 40 mph. Now the speedo and governor may not be perfectly accurate and maybe the train will creep up a couple of mph to 42, but that is rare and the train will eventually slow back down to 40 mph. As far as the 35 mph limit, I can't on the top of my head think of anyplace where there is a 35 mph limit. The T likes to make the speed limits odd so you will notice them. You will see 3 MPH, 6 MPH, & 10 MPH. I think there is one 8 MPH in the subway approaching Haymarket. Implied subway speed is 25 MPH. All platforms and crossings are an implied 10 mph. Riverside is the max at 40 mph. I can not think of anywhere where there is a 35 MPH speed limit. The radar is usually set up where the limit is 10 MPH which is excruciatingly slow and difficult for some operators to comply with and therefore easy for the radar inspectors to make their quotas. 35? That's a weird one.
 
The bike path has received a base coat of asphalt between the current terminus and Somerville Junction Park. I will take the under on one month before some folks ignore the fences.
 
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