Green Line Extension to Medford & Union Sq

[themissinglink]

For prioritizing rail transit extensions, I'd put the Red-Blue BLX Connector and the BLX to Lynn as way ahead of GLX to Mystic Valley Pkwy.

I agree, although I feel like an extension to Mystic Valley Parkway should still happen sooner rather than later since it was cut from the GLX.

 

[Teban54]

I agree, although I feel like an extension to Mystic Valley Parkway should still happen sooner rather than later since it was cut from the GLX.

And also because it's (hopefully) a degree of magnitude cheaper than Red-Blue, BLX to Lynn, OLX to either Roslindale* or West Roxbury, and even the somewhat comparable GLX to Porter. It's literally the low-hanging fruit.

* That's probably the only one with a chance of being as cheap as GLX to Mystic Valley.

 

[jbray]

This is a tough one for me to choose (outside of my vested interest living on the branch). The cost-reduction redesign precludes extension by removing the elevated station and bringing it down the ground. Yes, the momentum is there to be capitalized upon and that's really important to try and capture before it turns into another BLX (in either direction), but it's momentum to a squandered project that will cost much more to fix later.

In my mind, the ultimate goal of the project should be to get to Winchester Center as a (permanent?) terminus. West Medford and Wedgemere should come off the Lowell Line. At the very least West Medford should be the terminus with an transfer as part of the very real discussion around grade separation and redevelopment of West Medford (the place). The current GLX remainder is a bad plan and unless we can get it changed back, it should be left behind.

 

[fatnoah]

In my mind, the ultimate goal of the project should be to get to Winchester Center as a (permanent?) terminus.

It's crazy transit pitch material, but I always felt Woburn Center or even continuing further to Route 128 would be the best terminus. It has similar density to Winchester and worse access to downtown. While it has some express buses and the 134 (and I've taken them all) they're not convenient and the walkshed of the bus stops serves far fewer people than the driveshed of a real transit terminal w/parking in North Woburn/Burlington.

Wedgemere should come off the Lowell Line

Selfishly, I would love to see the GL make it to Winchester Center for a much more convenient trip to downtown. West Medford feels more realistic, though. It would catch the already decent CR traffic, serve as a transfer point for GL, and mesh well with buses along the RT 60 corridor.

 

[jbray]

It's crazy transit pitch material, but I always felt Woburn Center or even continuing further to Route 128 would be the best terminus. It has similar density to Winchester and worse access to downtown. While it has some express buses and the 134 (and I've taken them all) they're not convenient and the walkshed of the bus stops serves far fewer people than the driveshed of a real transit terminal w/parking in North Woburn/Burlington.

I'll probably respond to this over in crazy pitches to keep this thread centered.

Selfishly, I would love to see the GL make it to Winchester Center for a much more convenient trip to downtown. West Medford feels more realistic, though. It would catch the already decent CR traffic, serve as a transfer point for GL, and mesh well with buses along the RT 60 corridor.

Having both wouldn't be the end of the world. Considering that Alewife may soon have a proposed commuter rail station as part of the redevelopment, having two relatively close node interfaces isn't terrible. I was really just trying to speed up the Lowell line in anticipation of a northern extension. Keep local traffic local while also keeping enough connections to regional and express via regional viable.

 

[ceo]

Biggest problem with extending to West Medford, other than Medford people hate nice things, will be the bridge over the Mystic. Though if they can build a new bridge next to the old one, that would presumably be less expensive. The other issue is that extending GLX past West Medford will require grade-separating it and the commuter rail under Rte 60, which will be expensive and disruptive. Ain't saying it shouldn't be done, mind.

 

[Friend-Union]

Biggest problem with extending to West Medford, other than Medford people hate nice things, will be the bridge over the Mystic. Though if they can build a new bridge next to the old one, that would presumably be less expensive. The other issue is that extending GLX past West Medford will require grade-separating it and the commuter rail under Rte 60, which will be expensive and disruptive. Ain't saying it shouldn't be done, mind.

This Medford voter gives a thumbs up to grade separation at West Medford similar to Waverley station even without the GLX. Two way crossover traffic to and from Harvard Ave and Playstead Rd within 100' of the Lowell line, along with heavy pedestrian crossings creates a dangerous gridlock potential on the tracks, especially at night. I can also see the addition of GLX headways requiring a grade separation at Canal St as well. Leading to the tracks being put over Canal St if the distance from the river to Canal St is too short for a proper tunnel incline. West Medford also has the room for a layover and storage yard along Playstead Rd.

 

[jbray]

Here's F-Line's 2019 thoughts on this from page 146 of this very thread. Only F-Line can speak to whether it's still the current thought process but I thought it was worth mentioning because it details the challenges of the dual mode station with grade separation.

The opposition for "Phase II" so-to-speak was for an additional infill stop at Winthrop St. to flank the west end of Tufts campus. The Medford residents immediately adjacent to the station site kvetched about it, and it was deleted. In reality it wasn't that big a loss because the stop spacing from College Ave. to 16 merely went from slightly too short to slightly too long...but not off-scale in any meaningful way. The 3 buses on Boston Ave. still give very adequate coverage spanning the stops.

-------------------------

West Med was deleted way early on. The NIMBY'ism right by the station-proper was mild, but a bunch of hardcores out by Mystic Lakes and Wedgemere piled on the hysteria ("undesireables" blah blah blah) at town meetings and destabilized the whole works. But that was back in the stone age of 2005.

Crossing 16 & the Mystic would've added cost, but the Lowell Line arches could've easily been doubled-up with exact replicas. Bigger operational problems were the grade crossings. Canal St. probably would've needed to be closed because (despite lowish traffic) the sightlines aren't good at all for a 6-min. headway traffic saturation in addition to all future RR traffic increases. That crossing already has quadrant gates and plastic barriers for its relative danger. And the line would've had to stub out prior to the High St. crossing, requiring pretty cramped confines around the platforms, lousy egresses, property taking of the Dunkies parking lot, and residential impacts on Circuit St.

West Med's an easier mount when the time comes to finally grade separate the full RR...which will be a de facto build prerequisite of NSRL if the Lowell Line is expected to pair-match with the NEC to the south, or will be necessary at some point deeper into the RER area as traffic increases get intolerable. Half-undercut/half-overpass @ Canal coming off the Mystic, bottoming out into a full cut @ High. Since the ROW is 4-track width here due to a prehistoric thicket of freight sidings that used to be around Canal, and the West Med CR platforms are basically sitting on those 3rd/4th berths, the cut would be pre-provisioned for an equally grade separated GLX extension side-by-side. You would merely add the Mystic+16 bridges to connect. And possibly re-do 16 Station again up atop the embankment per the original future-proofing plan if now they're set on Phase II scaling back to a barebones ground-level stop.

The only catch with the RR grade separation future-proofing plan is that there would not be enough room to have West Med CR and GLX platforms together down in the cut. The GLX extension would have to eat the commuter rail stop...but that's not a big deal as a lot of ridership is going to migrate down the street from West Med CR to Route 16 GL to begin with and flip the mode shares accordingly. Getting there via the RR cut would also serve up a straight shot to extending the line further to at least the Winchester Ctr. parking lot (furthest you can go without budgeting for a short 1000 ft. subway under the Winch rotary). Path would be clear so long as the same GL-eats-CR platform scenario happened at Wedgemere, so you could think of the more distant-future RR grade separation as loading up for bear for an additional +3 (or +4 if you want a Mystic Lakes spacer) GLX extension for some multimodal goodness.

 

[RandomWalk]

Looks like the owner of 200 Inner Belt is adding a ground level entrance to East Somerville station across from the existing main entrance.

 

[Friend-Union]

Looks like the owner of 200 Inner Belt is adding a ground level entrance to East Somerville station across from the existing main entrance.

Does this mean a settlement and acquisition for yard expansion for double type 10 storage is also a go?

https://cdn.mbta.com/sites/default/files/2023-12/%236.%20Inner%20Belt%20Final%20Presentation%20to%20Board%20Public%20Session%20V12.12.23.pdf

 

[Teban54]

The other issue is that extending GLX past West Medford will require grade-separating it and the commuter rail under Rte 60, which will be expensive and disruptive.

Is there a reason why GLX past West Medford needs to be grade-separated? Sure, the current GLX is grade-separated, but it's still light rail that has the theoretical advantage of running through at-grade junctions when needed.

So if it's really deemed that grade-separating 4 tracks incurs significantly higher cost than 2 (which I think is unlikely based on F-Line's comment), one theoretical way to lower cost would be to build a bilevel station, with commuter rail below street level and GLX at grade. (Obviously, a fully grade-separated one for both GLX and CR would be more ideal.)

 

[Delvin4519]

Is there a reason why GLX past West Medford needs to be grade-separated? Sure, the current GLX is grade-separated, but it's still light rail that has the theoretical advantage of running through at-grade junctions when needed.

So if it's really deemed that grade-separating 4 tracks incurs significantly higher cost than 2 (which I think is unlikely based on F-Line's comment), one theoretical way to lower cost would be to build a bilevel station, with commuter rail below street level and GLX at grade. (Obviously, a fully grade-separated one for both GLX and CR would be more ideal.)

GLX already has a horrible bunching problem just with the at-grade junctions on the Huntington Ave. Branch. Northbound GLX service routinely has 20 - 27 minute gaps in service, followed by 2 or 3 trollies at once, with many of them going express. Otherwise it would be near impossible to run SUAG single digit headways. Of course if the T keeps it's terrible dispatching issues, then it would be needed to grade separate the GLX in full. The MBTA has to somehow make up the cost of providing terrible, terrible, terrible service on a brand new rail transit line.

"Median headway" of "9 minutes", but it's more like 15 minute headways at best. Barely even usable at all, and essentially forces the need of live updated timetables to even try to use the GLX.

(The image below shows off peak service. This is the post-COVID era of WFH since it's not 2019 anymore, less peak oriented than pre-COVID, and off peak headways on the MBTA are terrible. However even weekday headways often result in bunching with 15 - 20 minute gaps as opposed to 20 - 27 minute gaps during off peak hours).

West Medford being grade separated is a necessity. But any extra at-grade junctions after that will ever worsen the bunching problems more and more with a longer route and extra grade crossings. GLX past West Medford would already be adding a lengthy dose of extra runtime to its route milage through areas with relatively weak densities just to reach Winchester. At that point past West Medford, we'd need to give the GLX a dedicated downtown tunnel just to avoid the pain of running through the GL central subway tunnel.

 

[Charlie_mta]

Even at 9 minute headways, couldn't the at-grade crossing signals of a West Medford GLX be operated in favor of the rail transit, with cross-traffic stopped every time a train goes by, within reason of course. It seems that with transit activated and transit preferential signaling at the crossings, the impacts on the GLX operations would be minimal. The number of at-grade crossings there would be small compared to Huntington Ave.

 

[RandomWalk]

A couple of other notes on the GLX:

- Someone cut a hand-sized hole or two in the fencing for the pedestrian bridge over the Fitchburg Line.
- The screens used by the operators to view the platform cameras and verify the doors are clear have been removed from a few of the stations. Did they give up on them, or are they replacing them already?

 

[TheRatmeister]

Is there a reason why GLX past West Medford needs to be grade-separated? Sure, the current GLX is grade-separated, but it's still light rail that has the theoretical advantage of running through at-grade junctions when needed.

So if it's really deemed that grade-separating 4 tracks incurs significantly higher cost than 2 (which I think is unlikely based on F-Line's comment), one theoretical way to lower cost would be to build a bilevel station, with commuter rail below street level and GLX at grade. (Obviously, a fully grade-separated one for both GLX and CR would be more ideal.)

There is a third option, just not extending past W. Medford. If the Haverhill Line used a doubled Wildcat branch that would mean all day 15 minute (or better during the peak) headways on regional rail. Density along the line drops like a stone through Winchester and Woburn so frankly I don't expect 15 minutes headways to be a problem anytime soon.

 

[Riverside]

Could you explain how, exactly? I don't think the site at Mystic Valley Pkwy is really large enough to have either a turning loop or more than two stub-end platforms.

Going way back to this briefly: the question would be whether there is room for a lengthier set of tail tracks beyond the platform (ideally with crossovers), which increases the flexibility and capacity of turning operations significantly. The setup at Wonderland or Braintree are good examples.

At-platform turns essentially block the ROW; having two tracks obviously helps, but still becomes brittle quickly (particularly if one set needs to temporarily go OOS to reset some blinking light or whatever). And having the tracks end just beyond the platform sometimes introduces speed limits that wouldn’t exist if there was more running space beyond the station.

 

[TheRatmeister]

Going way back to this briefly: the question would be whether there is room for a lengthier set of tail tracks beyond the platform (ideally with crossovers), which increases the flexibility and capacity of turning operations significantly. The setup at Wonderland or Braintree are good examples.

Doesn't Medford/Tufts already have pretty long tail tracks? The only thing missing is a crossover. Even if those aren't long enough, I don't really see how extending to Mystic Valley Pkwy really helps more than just a short extension of the tracks that could be done with little or no land-taking.

 

[Riverside]

Doesn't Medford/Tufts already have pretty long tail tracks? The only thing missing is a crossover. Even if those aren't long enough, I don't really see how extending to Mystic Valley Pkwy really helps more than just a short extension of the tracks that could be done with little or no land-taking.

Yeah, I’m not sure whether the speed issue is present at Medford/Tufts — I suspect it’s more a factor at Union Square.

For comparison, the tails at Medford/Tufts are something like 520 feet (based on my quick measurement on Google Maps), while Wonderland is something like 1200 and Braintree is closer to 1500 (IIRC).

 

[737900er]

GLX already has a horrible bunching problem just with the at-grade junctions on the Huntington Ave. Branch. Northbound GLX service routinely has 20 - 27 minute gaps in service, followed by 2 or 3 trollies at once, with many of them going express. Otherwise it would be near impossible to run SUAG single digit headways. Of course if the T keeps it's terrible dispatching issues, then it would be needed to grade separate the GLX in full. The MBTA has to somehow make up the cost of providing terrible, terrible, terrible service on a brand new rail transit line.

"Median headway" of "9 minutes", but it's more like 15 minute headways at best. Barely even usable at all, and essentially forces the need of live updated timetables to even try to use the GLX.

(The image below shows off peak service. This is the post-COVID era of WFH since it's not 2019 anymore, less peak oriented than pre-COVID, and off peak headways on the MBTA are terrible. However even weekday headways often result in bunching with 15 - 20 minute gaps as opposed to 20 - 27 minute gaps during off peak hours).

West Medford being grade separated is a necessity. But any extra at-grade junctions after that will ever worsen the bunching problems more and more with a longer route and extra grade crossings. GLX past West Medford would already be adding a lengthy dose of extra runtime to its route milage through areas with relatively weak densities just to reach Winchester. At that point past West Medford, we'd need to give the GLX a dedicated downtown tunnel just to avoid the pain of running through the GL central subway tunnel.

Just pulling the data for the day you cite (which was a Saturday), I'd argue that it's the Central Subway that's responsible for more of the problems on GLX than Huntington Ave signals/traffic.
The Huntington Ave line entering the Subway doesn't actually look that bad compared to the Highland Branch which should be the best performer.

When it gets out of the Subway it's way worse, as you show.

This is of course why GLR is so important

 

[F-Line to Dudley]

Is there a reason why GLX past West Medford needs to be grade-separated? Sure, the current GLX is grade-separated, but it's still light rail that has the theoretical advantage of running through at-grade junctions when needed.

So if it's really deemed that grade-separating 4 tracks incurs significantly higher cost than 2 (which I think is unlikely based on F-Line's comment), one theoretical way to lower cost would be to build a bilevel station, with commuter rail below street level and GLX at grade. (Obviously, a fully grade-separated one for both GLX and CR would be more ideal.)

When GLX was still slated for West Med, they weren't thinking of grade-separating. Canal St. would retain its grade crossing, being a low-volume street (or the crossing could've just been blocked off cutting the street at little loss). And the extension would stub out at High St., not making the crossing. The problems were that the end-of-line station would've been incredibly cramped, with a single egress dumping out into the Dunkies parking lot causing a pedestrian free-for-all crossing the street. And the Lowell trains were still there making the crossing, which made management of the pedestrian swells that much worse. They couldn't design it in non-messy fashion, and the locals had justified concerns about the safety or lackthereof so the support for it was limited.

The crossings badly need to be eliminated. :15 Lowell/Haverhill RER service with increased Downeaster frequencies are going to push them to their outer limits on chaos management, and there aren't a lot of tricks up the sleeve for taming the carpocalypse with the crossings remaining. Quadrant gates would allow for the rail speed limit to be raised through there from 30 MPH to 60 MPH, but even signalizing the adjacent intersections with queue-dump tricks isn't going to do enough good to matter. It's one of the last crossings on the MBTA system to still have an on-duty crossing guard manually controlling the gates during peak, and that guard only gets busier...not eliminated...when Regional Rail amps up the all-day frequencies. Sinking the tracks is going to be a painfully expensive undertaking, but it is fully feasible (and is fully feasible without property takings at 4-track width as a future GLX provision, with or without any active proposal to GLX it there). One of these decades they're going to have to bite the bullet, because it's arguably the 1 or 2 worst crossings on the whole system today...nevermind with the frequencies yet to come.