Everett Transportation (SL3 extension, potential OLX/GLX, Sweetser Circle infill station)

[Charlie_mta]

Even that height isn't enough to get over buildings in dense areas, guesstimating on Google Earth suggests the viaduct at Northgate is around 3 stories tall, there are a lot of buildings along Broadway that are that tall or slightly taller. (We call them triple-deckers for a reason after all.) Sure it might feel less claustrophobic but it will still be dark.

The viaduct in the photo is 65 feet wide, so that would put trains literally next to windows on Broadway. That's probably not an option, and even if it was you've really just traded light in the middle of the street for light on the sides of the street. You could cut down the space in the middle to put it back out towards to sides, but again we're just choosing where the open space goes here, we can't magically make the street wider, so I'm not sure it would really make a big difference.

Here's a typical section from the SoundTransit website. The column itself looks to be 30 ft. tall and 5.5 ft. wide. I'd do some other measurements in regards to how well it would fit onto Broadway in Everett, but I was in an accident a few days ago wherein I broke my glasses and my nose, am recovering well but can't see the screen all that great. But anyway, something like the typical below on center piers down the middle of Broadway wouldn't be so bad, IMO. I'd look up the generic cost of a subway vs. an elevated, but like I say my vision is a bit compromised right now.

 

[Riverside]

Here's a typical section from the SoundTransit website. The column itself looks to be 30 ft. tall and 5.5 ft. wide. I'd do some other measurements in regards to how well it would fit onto Broadway in Everett, but I was in an accident a few days ago wherein I broke my glasses and my nose, am recovering well but can't see the screen all that great. But anyway, something like the typical below on center piers down the middle of Broadway wouldn't be so bad, IMO. I'd look up the generic cost of a subway vs. an elevated, but like I say my vision is a bit compromised right now.

View attachment 59925

So sorry to hear about your accident! Hope you're okay and recovering well.

Assuming all the pieces are to scale, it looks like their recommended "vegetation clear zone" is 45 feet wide. Choosing a random spot along Broadway, sidewalk-to-sidewalk is 44 feet. I agree that the column is about 5.5 feet wide, so probably you'd need to lose parking on at least one side of the street to make space. The guideway itself is 22 feet; however, the Green Line viaducts (both GLX and south of Science Park) are more like 32 feet wide. Looks like sidewalks themselves are 12 feet wide each. So overall building-building length is ~68 feet, which is consistent with what I see on the satelite.

That would mean anywhere from 18 to 23 feet from the edge of the viaduct to building windows. And, as suggested by the mockup below, at the heights suggested here, trains would actually be potentially running higher than a three-decker (although many three-deckers have their first floor lifted above the ground, so there would still be some overlap). Stations would probably add another 20 feet of width, so those would definitely be quite close to windows.

I used Streetmix and Paint.NET to try to do a mockup of what it might look like with an elevated of that height and either a 20 or 30 foot-wide viaduct.

I'll be honest: to me, the width is less of a concern than the height. (I say, having never myself lived with a train running 20 feet away from my window, which is to say that the width may well still be a big issue.) But as for the height: I don't have anything concrete (or professional) to back this up, but to me it just looks overtall for the space. It won't cast as much of a direct top-down shadow, but it will block angular sunlight, so it would still impact the street below.

I'll let @Teban54 check me on this, but I think we've guesstimated elevated cost-per-mile to be roughly half that of tunneled (e.g. $500M instead of $1B, but, as ever, those numbers vary widely, and it's easily conceivable that there would specific scenarios where those numbers would overlap or even swap).

What I will say, though: a Phase 1 subway to Everett Sq with provisions for Phase 2 would only require ~3000 feet of tunnel from Sweetster Circle. Maybe more depending on where you want the station, but equally so could be less. (For example, if you could make it to the interior of Sweetster Circle in open cut, and you put your "Square" station at 2nd St, the tunnel would only be 1500 feet, which is shorter than Red-Blue.

You would then be set up for a Phase 2 extension to Ferry St, where the community is already enjoying at least some benefits of having an in-city transit stop, as opposed to having to tear up Broadway for multiple years and just live in pain for the duration. Plus, with a Phase 1 cut-and-cover to 2nd St, you would then have a stronger base of ridership to justify the costlier-but-less-disruptive option of running a TBM through the hill, leaving the neighborhood largely untouched, except at Ferry St station itself.

 

[bigpicture7]

...having never myself lived with a train running 20 feet away from my window, which is to say that the width may well still be a big issue.

Seems like these people could provide some insight as to how well it could go. There isn't even a sound barrier on this side; seems all dependent on how well the residences' windows are soundproofed.

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[Charlie_mta]

So sorry to hear about your accident! Hope you're okay and recovering well.

Assuming all the pieces are to scale, it looks like their recommended "vegetation clear zone" is 45 feet wide. Choosing a random spot along Broadway, sidewalk-to-sidewalk is 44 feet. I agree that the column is about 5.5 feet wide, so probably you'd need to lose parking on at least one side of the street to make space. The guideway itself is 22 feet; however, the Green Line viaducts (both GLX and south of Science Park) are more like 32 feet wide. Looks like sidewalks themselves are 12 feet wide each. So overall building-building length is ~68 feet, which is consistent with what I see on the satelite.

That would mean anywhere from 18 to 23 feet from the edge of the viaduct to building windows. And, as suggested by the mockup below, at the heights suggested here, trains would actually be potentially running higher than a three-decker (although many three-deckers have their first floor lifted above the ground, so there would still be some overlap). Stations would probably add another 20 feet of width, so those would definitely be quite close to windows.

I used Streetmix and Paint.NET to try to do a mockup of what it might look like with an elevated of that height and either a 20 or 30 foot-wide viaduct.

View attachment 59934

View attachment 59935

I'll be honest: to me, the width is less of a concern than the height. (I say, having never myself lived with a train running 20 feet away from my window, which is to say that the width may well still be a big issue.) But as for the height: I don't have anything concrete (or professional) to back this up, but to me it just looks overtall for the space. It won't cast as much of a direct top-down shadow, but it will block angular sunlight, so it would still impact the street below.

I'll let @Teban54 check me on this, but I think we've guesstimated elevated cost-per-mile to be roughly half that of tunneled (e.g. $500M instead of $1B, but, as ever, those numbers vary widely, and it's easily conceivable that there would specific scenarios where those numbers would overlap or even swap).

What I will say, though: a Phase 1 subway to Everett Sq with provisions for Phase 2 would only require ~3000 feet of tunnel from Sweetster Circle. Maybe more depending on where you want the station, but equally so could be less. (For example, if you could make it to the interior of Sweetster Circle in open cut, and you put your "Square" station at 2nd St, the tunnel would only be 1500 feet, which is shorter than Red-Blue.

You would then be set up for a Phase 2 extension to Ferry St, where the community is already enjoying at least some benefits of having an in-city transit stop, as opposed to having to tear up Broadway for multiple years and just live in pain for the duration. Plus, with a Phase 1 cut-and-cover to 2nd St, you would then have a stronger base of ridership to justify the costlier-but-less-disruptive option of running a TBM through the hill, leaving the neighborhood largely untouched, except at Ferry St station itself.

Thank you for your detailed and accurate analysis. It appears that a subway for rail transit is best for streets of this width class. Elevated lines have a future in the Boston area on wider streets, boulevards and highways, but not on narrow streets such as Broadway in Everett wherein residential and commercial buildings are in place immediately next to the sidewalks.

 

[Charlie_mta]

Seems like these people could provide some insight as to how well it could go. There isn't even a sound barrier on this side; seems all dependent on how well the residences' windows are soundproofed.

Google Maps

Find local businesses, view maps and get driving directions in Google Maps.

maps.app.goo.gl

The big difference with the O'Brien Hwy development next to the GL viaduct is that the viaduct was there first, and the residential development was built after, So, the residents are moving into a situation that is pre-existing. In the case of Broadway in Everett, those buildings have been in place for decades without an elevated line close by.

 

[TheRatmeister]

I'll be honest: to me, the width is less of a concern than the height. (I say, having never myself lived with a train running 20 feet away from my window, which is to say that the width may well still be a big issue.) But as for the height: I don't have anything concrete (or professional) to back this up, but to me it just looks overtall for the space. It won't cast as much of a direct top-down shadow, but it will block angular sunlight, so it would still impact the street below.

If we're just running a viaduct, it's not that bad. People would certainly hate it but in the grand scheme of things done to places it's reasonably low on the harm levels. If this were a way to connect two sections of elevated rail on open ROWs or wide streets, I would consider it to be politically challenging but an acceptable solution. But as soon as you add 20ft of width for stations on a street like Broadway, stations which are going to be located in the densest areas with the tallest buildings, then it becomes very bad. That's how you get 10ft or less of clearance to buildings on either side, and I think we can all agree that's pretty miserable for basically everyone involved.

 

[737900er]

I do think elevated rail could be interesting south of Revere Beach Parkway if you wanted to deviate from the existing RoW, because very few people live there right now. But wow the Encore really gets in the way when you start to crayon.

 

[TheRatmeister]

I do think elevated rail could be interesting south of Revere Beach Parkway if you wanted to deviate from the existing RoW, because very few people live there right now.

Absolutely, I still think elevated over Alford/Broadway is the better alignment for proximity both to Encore and redevelopment of the Everett Hellscape™

But wow the Encore really gets in the way when you start to crayon.

I don't think it does, I would argue navigating Sullivan and the Charlestown Garage is more challenging IMO. If you don't want to be stuck running behind the delivery bays of Encore you need some way to get under the Newburyport/Rockport line and then rise up fairly quickly to a bridge over the Mystic River that's high enough to have sufficient clearance for ships. Even the 'easy' route still has you navigating under the Orange Line and Haverhill Line before needing to climb real quick to get enough height clearance, potentially needing something like a 5% grade.

 

[jbray]

I do think elevated rail could be interesting south of Revere Beach Parkway if you wanted to deviate from the existing RoW, because very few people live there right now. But wow the Encore really gets in the way when you start to crayon.

Absolutely, I still think elevated over Alford/Broadway is the better alignment for proximity both to Encore and redevelopment of the Everett Hellscape™

I don't think it does, I would argue navigating Sullivan and the Charlestown Garage is more challenging IMO. If you don't want to be stuck running behind the delivery bays of Encore you need some way to get under the Newburyport/Rockport line and then rise up fairly quickly to a bridge over the Mystic River that's high enough to have sufficient clearance for ships. Even the 'easy' route still has you navigating under the Orange Line and Haverhill Line before needing to climb real quick to get enough height clearance, potentially needing something like a 5% grade.

That would make it less well connected for Assembly Square. To me, that's a goal that should be on the table given that we talk elsewhere about how much the core is burdened by people needing to force transfer just for an additional stop or two and Assembly is a growing hub of residential and business. I also think that Gateway center is going to blow up with redevelopment given that it doesn't need to be remediated at as much expense. There is no doubt that Broadway as a ROW is easier, but it feels less suitable for the Ring and more oriented toward New Rutherford. An alternate way to conceive it all may be to consider that both ROWs should be used eventually so that the UR and Everett subway can be separated although that is certainly an expensive additional step and not how it will probably be scoped out.

 

[Stlin]

I'm just going to pull into this thread my personal concept for transit along this corridor, with some minor updates over the past year.

This is what I've been thinking of as the "Brown X," an interlining concept taking advantage of the relative dimensional compatibility* of the Blue and Orange Lines.

Spoiler: *Dims

While Blue Line cars are some 17ft shorter, they're the same width, and only 3½ inches shorter to the platform. With the future elimination of Bowdoin's restrictive curve, I understand that there's a possibility of further lengthening the BL platforms to accommodate OL length cars, and the platform height difference is within the range of adjustable ballasts - something that be accommodated on the fleet by equiping it off with automatic air ballasts. Even if you don't lengthen BL platforms, an expansion of the BL fleet and having X routes served by only Blue equipment would be entirely possible.

In a world where BLX to Lynn exists, such interlining implies 6 potential endpoint combinations, such as direct Oak Grove to Lynn service, or MGH to Forest Hills. Now, outer terminal to outer terminal routings that don't cross downtown are admittedly unlikely to have sufficient ridership to justify their existence, but a more limited subset of 4 that would make a ᚸ to include Forest Hills to Lynn or Oak Grove to MGH via Airport? It'd allow someone living in Malden to have a one seat ride to the airport, or someone living in Lynn to have a one seat to back bay - and the effect would only be magnified further with further extensions of the feeding lines. With the X model, those outer terminii routings that don't justify a direct train are still enabled by stops in Chelsea - a single same platform transfer, effectively serving as a segment of the urban ring. Additionally, if you keep the service feeds symmetrical, you shouldn't affect total trains at the major transfer points or terminii, since trains from the other endpoint would substitute for those diverted onto the X, unlike in a branching service. Those Chelsea serving trains would indisputably see an increase in end to end travel times, but by eliminating potential downtown transfers (since an BL rider can now take a somewhat more circuitious routing to get to a closer downtown stop, or OL direct access to MGH) and since you're not eliminating the prior service? with traditional transit frequencies it shouldn't be too burdensome, and as capacity decreases would only occur in between the crossing legs. In my crayon, that only affects Assembly on the OL, but does affect the majority of the outer Blue until it rejoins the Eastern route, but that would probably be negotiable especially with a Lynn or especially a Salem extension.

In terms of constructability, it's using extant and mostly grade separated right of way. I haven't thought too much about station siting, but for the moment I'm assuming there's space along the corridor. There's a single digit number of grade crossings that'd need curing, notwithstanding any necessary bridge mods. On the Blue side from the Airport I'd fork and eat the grade separated Couglin Bypass until you get to the Chelsea Creek, tunneling under and popping out past Cottage Street. The existing SL RoW through Chelsea would need grade separation between 2nd st and Arlington, but that's less than a mile of relatively simple C&C or just trenching it. The other Leg north can just share RoW with the Eastern route, which I understand to be largely quad track width until it rejoins the Blue at Wonderland. (Eastern Ave would either need a up or under situation) On the Orange side, you'd need a flyover crossing of the Mystic, branching out either side of Assembly station. Given the grades that the OL can handle relative to CR, it shouldn't be too difficult. Alternatively, since we've been discussing OL diversions, making it a megaproject you could tunnel under the Northern Strand and rejoin the OL just south of Malden Center.

I