Red Line Extension to Arlington Heights

[JeffDowntown]

I've never been convinced that Arlington and Lexington have the population density to make RLX worthwhile.

Arlington's density is 9,000 people per sq mile, significantly higher than Quincy (6,200 per sq mile), for example. (And Quincy has 4 Red Line stops.)

 

[jklo]

I've never been convinced that Arlington and Lexington have the population density to make RLX worthwhile.

Lexington definitely. But there's value in a P&R if you could get to Burlington/Burlington Mall. And given that I've always thought Arlington was more against having Arlington be the last stop (in order to not get the Last Stop traffic) you might have to go that far anyway if you were to do it.

 

[TheRatmeister]

I've never been convinced that Arlington and Lexington have the population density to make RLX worthwhile.

Arlington absolutely does. East Arlington/Arlington center have similar population density to Mattapan or Roxbury. Then go a bit further to Arlington Heights for a good bus hub and a small yard to put a nice bow on the extension.

 

[F-Line to Dudley]

Alewife is an absolutely dysfunctional bus hub, and was never intended to host as many routes via the Route 2 frontage roads as it did after the Arlington Heights extension was canceled in the 70's. It's an operational quagmire because of the traffic problems around Alewife, and the frequencies suck because the equipment cycling sucks amid all those traffic problems. The northwest-region bus system is a lot healthier in schedule adherence, frequency, and coverage if Arlington Center and Arlington Heights each host substantial bus hubs at the Red Line stations and Alewife gets vacated of everything except the 83, the LEX Alewife express bus up Route 2 to the 128 office parks, and maybe some future backfill Medford and Watertown circumferential routes along the parkways. To go along with what everybody's said about Arlington's very rapid transit-worthy population density, there's great need for correcting the major bus circulation deficiencies in the northwest region and RLX to Heights directly accomplishes that for not-too-onerous money because of the easy capped-cut tunneling under the trail. It's an exponential mobility improvement to the whole region with the bus dimension factored.

I fully agree that Lexington probably doesn't have the density to merit an extension in the foreseeable future, and you probably wouldn't be able to bury the Red Line under the trail like was planned Alewife-Heights in the 1970's so the Minuteman's fate out there would be a very divisive issue (as opposed to a non-issue in Arlington where the trail would go back better than before). But in the meantime their buses (and the 350 to Burlington if Arlington Center is its terminus) work really well and would support much greater frequencies if they're hubbed at the two RLX stops instead of either shooting their cycling loads en route to/from Alewife or requiring double-transfers to reach rapid transit. The project would have long and fruitful multimodal coattails if built.

 

[kingofsheeba]

Alewife is an absolutely dysfunctional bus hub, and was never intended to host as many routes via the Route 2 frontage roads as it did after the Arlington Heights extension was canceled in the 70's. It's an operational quagmire because of the traffic problems around Alewife, and the frequencies suck because the equipment cycling sucks amid all those traffic problems. The northwest-region bus system is a lot healthier in schedule adherence, frequency, and coverage if Arlington Center and Arlington Heights each host substantial bus hubs at the Red Line stations and Alewife gets vacated of everything except the 83, the LEX Alewife express bus up Route 2 to the 128 office parks, and maybe some future backfill Medford and Watertown circumferential routes along the parkways. To go along with what everybody's said about Arlington's very rapid transit-worthy population density, there's great need for correcting the major bus circulation deficiencies in the northwest region and RLX to Heights directly accomplishes that for not-too-onerous money because of the easy capped-cut tunneling under the trail. It's an exponential mobility improvement to the whole region with the bus dimension factored.

I fully agree that Lexington probably doesn't have the density to merit an extension in the foreseeable future, and you probably wouldn't be able to bury the Red Line under the trail like was planned Alewife-Heights in the 1970's so the Minuteman's fate out there would be a very divisive issue (as opposed to a non-issue in Arlington where the trail would go back better than before). But in the meantime their buses (and the 350 to Burlington if Arlington Center is its terminus) work really well and would support much greater frequencies if they're hubbed at the two RLX stops instead of either shooting their cycling loads en route to/from Alewife or requiring double-transfers to reach rapid transit. The project would have long and fruitful multimodal coattails if built.

At this point, the only way to unfvck the inner-128 belt is to to pray for an apocalypse. That way, we can go in and fix what was supposed and what can still be.

Personally, I’ve given up hope trying to reason with NIMBYS. These killjoys want to help themselves. I can’t take another ten years of public comment and cost overruns. Just let Massachusetts crumble. Also let the United States crumble while we’re at it.

 

[stick n move]

A Green Line extension from Union Square along the Minuteman ROW has sometimes seemed more fit-for-purpose for Arlington to me -- better match for the Newton-like density (though see below), and better able to interface with the surface environment with grade crossings. But, I think last time I/someone else looked, it seemed unclear that there was enough width to fit both an LRT ROW and a bike path. (Center-running lanes on Mass Ave are also interesting, but that would be a lot of traffic lights + intersections to negotiate.)

That being said, I think the density is not actually what it looks like at first glance. Below are some modified screenshots of @Teban54's amazing population density map, in which I've removed color from tracts that are less dense than the tracts around the Newton Highlands and Newton Centre stations (which I've colored gold); the green and increasingly darker blue tracts are more and increasingly dense. All screenshots at the same zoom and scale.

View attachment 56100


View attachment 56101
View attachment 56102
View attachment 56103
As we can see, Arlington is actually significantly denser than the Green Line's sections of Newton. It is more comparable to Watertown and the north-of-Pike Newton neighborhoods, and not far off from Roslindale/West Roxbury. And the southern half of Arlington is basically on par with Quincy. Now, I'm not saying that such density demands heavy rail, but I do think it's worth highlighting.

~~~

Last summer, @ritchiew raised the idea of extending to Arlington via Mass Ave (potentially bypassing Alewife), and I think the justification holds:

This becomes all-the-clearer when looking at the population density map above; Arlington south/east of Arlington Center is way denser than the north (comparable to Allston/Brighton) and is centered on Mass Ave, not the Minuteman.

If we're gonna need to tunnel (and all the more so if we're gonna need to use a TBM to avoid disrupting the surface -- whether Mass Ave or the Minuteman), then it seems worth tunneling to the places where more people live and where new subway stations will be more useful.

~~~

Finally -- and I'm aware this is off-topic and represents a larger political gripe of mine -- from what I can tell, the Minuteman is estimated to have 2 million users per year. That comes out to an average of five or six thousand users per day. To put that number into context, that's around the same number of riders as at a single station like Braintree or Jackson Square or Fields Corner. It also happens to be less than the total ridership of the 77, which has roughly 7,000 daily riders.

The Minuteman is a beautiful linear park and obviously is valuable to its surrounding communities. But (temporarily) closing it for construction of a much higher capacity subway is not unreasonable.

This is an interesting idea. Routing the red line up mass ave seems to make the most sense as far as putting the train where the densest parts of arlington are. The old rail line and in turn now the minuteman was not designed to be a transit route therefore it kind of skirts off to the side of the densest areas until it eventually reaches mass ave, whereas mass ave itself goes right through the center of the densest parts of Arlington. Spy pond being right up against the minuteman also creates a huge hole in the catchment area where there are no people. Mass ave avoids these problems.

The biggest problem here is youd lose alewife as a red line station, but if this extension was done in concert with a new regional rail station at alewife, or even a new glx station I think that would help make up for it. Also if you have to use cut and cover regardless of whether it follows the minuteman or mass ave then it seems you should get the most bang for your buck and build the option that serves the most people. Adding the regional rail station at alewife would serve the growing neighborhood and stop them from losing transit access, but would also help keep park and ride pressure from just moving to arlington because it would still be available at alewife.

Something like this seems like itd make a lot of sense, I only added 2 stations (plus alewife) for the illustration but that could be adjusted whichever way. The line connects back to the minuteman at arlington center so from there on it could go as far as needed and would have room for future extensions.

 

[The EGE]

There's no way that survives a cost-benefit analysis, for a number of reasons.

• Because the existing tunnel goes all the way to Thorndike Park, building the tunnel under Mass Ave would add about 0.6 miles of additional tunneling.
• The Minuteman has minimal buried utilities, and there are plausible diversion routes south of Arlington Center for bike traffic. Mass Ave has a lot more utilities and traffic to deal with.
• Going via Mass Ave would require curves at North Cambridge and Arlington Center, both of which would require taking buildings
• The North Cambridge connection would also require cutting into the active Red Line tunnel, resulting in a prolonged period of service terminating at Davis. Connecting to the existing tail track tunnel would require minimal interruption to service.
• Between those four factors, you're probably talking something like a quarter to half a billion dollars of additional cost just for tunneling.
• Alewife is a valuable Red Line station to have. It intercepts Route 2, Alewife Brook Parkway, and trails in all directions. The Alewife triangle is very dense (and becoming less auto-oriented) and a significant ridership driver in its own right. A Green Line or Fitchburg Line station would have lower frequency than the Red Line, and wouldn't connect to as many key destinations (particularly Kendall).
• If there's ever a desire to have the Red Line to both Arlington and Waltham, Alewife is a much better spot for a flying junction than North Cambridge.
• East Arlington isn't a slam-dunk station location. There's some moderate-sized apartment blocks and triple-deckers, but it's mostly one-story retail flanking Mass Ave. There's no major commercial center, no intersecting bus routes or trails, no major attractors. It's more like Shawmut or Savin Hill than Porter or Davis. It's worth studying, especially if Arlington is willing to consider densifying it as a node, but there's no guarantee you build it at all.
• And if East Arlington really is that valuable, you can just put a stop on the Minuteman at Lake Street. It's all of a quarter-mile away from Mass Ave.

EDIT: Just to be clear, I think this is an interesting idea and I appreciate you bringing it up., even if I don't think it's practical.

 

[-anarresti-]

I really like the concept of RLX for many reasons; I live off the RL, I enjoy Arlington Center, and love the Minuteman (and my experience of it would be enhanced knowing that with RLX it would be the very best version of itself). So there is definitely a selfish element in my wish for this project to happen. It is near to my heart. But it's also an "easy" project that just makes sense for a multitude of reasons that have been expounded here and elsewhere many times.

With that said, I don't think the constituency behind this is big (nor loud) enough to gin up the support required at the state level to turn this into the "standard-bearer" transit expansion project that it would need to be under ordinary circumstances in order to get done (because as we know, we have trouble doing more than one major capital project/system expansion at a time).

Unlike GLX, there is nothing binding the state to carry this out, and even that project was difficult enough to get finished. So not only does the cost-benefit have to be there (which it very likely is to be fair), but the tradeoffs inherent in any this-project vs that-project calculation need to feel rational to a big enough constituency and at least palatable to even more, and Arlington is neither an environmental justice community, nor the densest area not served by rapid transit, nor many other things that could help its case. And so it faces an uphill battle.

But if we were to imagine a friendlier federal relationship and the potential for some money to flow in (so many of these thought exercises really need to start under that premise!), and we were to place RLX in a family of lower-cost, lower-stakes expansions that could take place across the system all at once or in quick sequence, and pitch it (and maybe manage it?) as one project, then we might be able to address the consituency problem by "spreading the wealth around" and would therefore be able to focus on the cost-benefit analysis on its own, rather than defend it against other priorities. Those projects, which I think of as a "minimum-viable system expansion" are:

1. Red-Blue connector
2. OLX to Roslindale Village
3. RLX to Arlington Center (or Heights)
4. And perhaps, infill stations at Rivers Edge and/or Neponset

This set of projects have an obvious constituency; they target each heavy rail line, the northside of the service area, the southside of the service area, and the core. It has benefits for higher income areas, lower income areas, and environmental justice communities. It's cheap-ish, and signals forward momentum for the region. To me, that feels like a winning proposition.

Now, something very important that shouldn't be left out of the discussion: Is this idea of a "minimum viable system expansion" actually worth doing if our region were to receive an influx of transportation dollars, as opposed to a single larger project that might take a similar amount of total money? Because then we get back to the question of politics. Though I can think only of BLX to Lynn or some regional rail electrification as alternatives that would occupy a smiliar cost-category (but base this solely on vibes and am open to hearing more alternatives). The Urban Ring, NSRL, green line reconfiguration, etc. are in a different universe and so probably wouldn't compete in the same space.

Everything preceeding is just my opinion and might be completely off-base.

TL;DR: The state does the above projects and RLX gets done; it doesn't do all of them, and it doesn't get done.

 

[ritchiew]

This is an interesting idea. Routing the red line up mass ave seems to make the most sense as far as putting the train where the densest parts of arlington are. The old rail line and in turn now the minuteman was not designed to be a transit route therefore it kind of skirts off to the side of the densest areas until it eventually reaches mass ave, whereas mass ave itself goes right through the center of the densest parts of Arlington. Spy pond being right up against the minuteman also creates a huge hole in the catchment area where there are no people. Mass ave avoids these problems.

The biggest problem here is youd lose alewife as a red line station, but if this extension was done in concert with a new regional rail station at alewife, or even a new glx station I think that would help make up for it. Also if you have to use cut and cover regardless of whether it follows the minuteman or mass ave then it seems you should get the most bang for your buck and build the option that serves the most people. Adding the regional rail station at alewife would serve the growing neighborhood and stop them from losing transit access, but would also help keep park and ride pressure from just moving to arlington because it would still be available at alewife.

Something like this seems like itd make a lot of sense, I only added 2 stations (plus alewife) for the illustration but that could be adjusted whichever way. The line connects back to the minuteman at arlington center so from there on it could go as far as needed and would have room for future extensions.
View attachment 72789

Hehe. You appear to be replying to a reply of something I wrote three years ago. Time flies. I still think it's a shame the RLX will skip East Arlington, but also, trying to include a station there only leaves bad options. What you have here is probably best among bad options.

Just thinking it though: I've seen a really rough heuristic of allowing ~$100,000 per new, daily ride for transit projects (which is probably generously high). @The EGE eyeballs the added cost for tunneling as low as ~250M-500 (which is definitely generously low). That would mean the station at Mass and Lake would need to induce ~2,500-5,000 new rides per day. About 8000 people live within a half mile, so you'd need ~15-30% of them taking two rides a day (one inbound, one outbound). That's extremely back-of-the-envelope math, with every assumption tilted in your favor, and skipping tons of nuance. But the result isn't outlandish. I think it's hard to confidently reject as a bad idea just eyeballing it. But I also doubt a cost-benefit-analysis would hold up when you start plugging in even slightly less favorable numbers.

That's also ignoring that you'd drop Alewife, which already has 11k boardings per day. If there were a CR stop, and real Regional Rail frequencies, and a NSRL, then it would make a lot more sense. So what comes first, NSRL or RLX? <shrug>

East Arlington isn't a slam-dunk station location. There's some moderate-sized apartment blocks and triple-deckers, but it's mostly one-story retail flanking Mass Ave. There's no major commercial center, no intersecting bus routes or trails, no major attractors. It's more like Shawmut or Savin Hill than Porter or Davis. It's worth studying, especially if Arlington is willing to consider densifying it as a node, but there's no guarantee you build it at all.

I agree with basically everything in your list, and probably your conclusion. But here, the benefit of an East Arlington station is residential density. It's surrounded by duplexes on small lots, which makes it fair bit denser than any other part of Arlington. There are some numbers in my post from years ago. It's denser than either of the other two proposed stops. And it's not like there's no business there. There are shops, a library, schools, a historic theater. It's not nothing. It would absolutely be a station as well used as the other in Arlington. It's just a question of the cost of not following the Minuteman.

And if East Arlington really is that valuable, you can just put a stop on the Minuteman at Lake Street. It's all of a quarter-mile away from Mass Ave.

That's certainly possible. I wrote before, even putting an East Arlington station on the Minuteman at Lake Street probably has a better residential catchment than central Arlington. But also, putting a station a 1/4 mile from where it ought to be is really a problem. It makes transit less convenient, so people use it less. Shawmut is less than 1/4 miles from Dot Ave. and it's a worse station because of it. In this specific case in Arlington, 1/4 miles to west moves the catchment area to include a lot more highway and Spy Pond, but away from Broadway, where people actually live. It is also possible to have some but service on Mass Ave, but Lake Street, not so much.

 

[F-Line to Dudley]

Hehe. You appear to be replying to a reply of something I wrote three years ago. Time flies. I still think it's a shame the RLX will skip East Arlington, but also, trying to include a station there only leaves bad options. What you have here is probably best among bad options.

Just thinking it though: I've seen a really rough heuristic of allowing ~$100,000 per new, daily ride for transit projects (which is probably generously high). @The EGE eyeballs the added cost for tunneling as low as ~250M-500 (which is definitely generously low). That would mean the station at Mass and Lake would need to induce ~2,500-5,000 new rides per day. About 8000 people live within a half mile, so you'd need ~15-30% of them taking two rides a day (one inbound, one outbound). That's extremely back-of-the-envelope math, with every assumption tilted in your favor, and skipping tons of nuance. But the result isn't outlandish. I think it's hard to confidently reject as a bad idea just eyeballing it. But I also doubt a cost-benefit-analysis would hold up when you start plugging in even slightly less favorable numbers.

That's also ignoring that you'd drop Alewife, which already has 11k boardings per day. If there were a CR stop, and real Regional Rail frequencies, and a NSRL, then it would make a lot more sense. So what comes first, NSRL or RLX? <shrug>


I agree with basically everything in your list, and probably your conclusion. But here, the benefit of an East Arlington station is residential density. It's surrounded by duplexes on small lots, which makes it fair bit denser than any other part of Arlington. There are some numbers in my post from years ago. It's denser than either of the other two proposed stops. And it's not like there's no business there. There are shops, a library, schools, a historic theater. It's not nothing. It would absolutely be a station as well used as the other in Arlington. It's just a question of the cost of not following the Minuteman.


That's certainly possible. I wrote before, even putting an East Arlington station on the Minuteman at Lake Street probably has a better residential catchment than central Arlington. But also, putting a station a 1/4 mile from where it ought to be is really a problem. It makes transit less convenient, so people use it less. Shawmut is less than 1/4 miles from Dot Ave. and it's a worse station because of it. In this specific case in Arlington, 1/4 miles to west moves the catchment area to include a lot more highway and Spy Pond, but away from Broadway, where people actually live. It is also possible to have some but service on Mass Ave, but Lake Street, not so much.

The continued existence of the 77 makes borderline considerations for an East Arlington stop a lot less fraught. It probably has to be the Minuteman ROW full-stop because utility relocation is such a freaking huge variable in tunneling costs, and the Minuteman has virtually none of that to contend with helping its cost-benefit enormously. The only places we could ever afford to C&C tunnel under old streets with massive utility relocations and hope to see a ridership payoff are either extremely high-priority systemwide-mobility corrective projects like Red-Blue or systemwide-mobility transformation projects like the Urban Ring or various GLR appendages that flush multiple tens of thousands of new riders into the system from improved transfers. You're not going to find a favorable cost-benefit for C&C under Mass Ave. to a hopefully-upzoned Mass @ Lake stop...the density's just too mid to offset the enormity of the costs, even if it's superficially "good". And Lake St. on the Minuteman is unfortunately in the hardest-to-upzone part of E. Arlington...near-100% residential with few to no avenues for cramming any more mixed use. It would probably perform much worse than the at least *somewhat* mixed-use environments around Savin Hill and Shawmut because that residential skew would tilt so heavily to ridership at peak commute times with very empty off-peaks when few people are home and there are few reasons to visit. That puts a pretty low cap on what ridership you'd be able to generate with all-day mainline Red Line frequencies. It would very nearly be among the loss leaders on the entire HRT system, whereas Arlington Center and Arlington Heights would slot right in with the Porters and Davises of the world because of their individual heft as squares and for bus connections.

But the 'tweener areas don't go unserved any more than North Cambridge goes unserved by the lack of another Red intermediate between Davis and Alewife because the 77 is still there, and figures to still remain at Key Route frequencies because of the consistent all-day ridership overchurn it gets from intermediate Mass Ave. destinations. You just need to destress it with the additional Arlington Center and Arlington Heights rapid transit transfers to segment the intermediate lengths into manageable-loading chunks like the 1980's Red extension did so well for destressing North Cambridge. A lot of RLX's ridership is going to come from two-seat trips because of the much-improved bus connections. And while it certainly is going to divert a lot of 77 ridership at the major squares like the 1980's extension did, it's only going to increase the granular trips to 'tweener Mass Ave. designations because the transfers get so much easier. I could see the whole of Mass Ave. Arlington getting upzoned even just with a two-stop AC + AH extension. The between-points get that much bus-enhanced, and the two-seat trips get that much more effortless. And the fact that the trail goes back in better-than-before just adds another dimension to that. So I think there's a good reason why the RLX debate has never gotten bogged-down in hair-splitting about lower-margin intermediate stops (even ones that existed on Lexington Branch CR service like Lake St. and Brattle St. halfway between Center and Heights). They see the template for their future in what North Cambridge ultimately got after the 1980's extension: a multimodal revolution.

 

[393b40]

Theres no way the abutters of the path through Arlington dont throw a shit fit. Red Line trains just below surface would have significant noise and vibration impact on all those households.

I think you would have to deep bore all the way to Arlington to deal with modern political reality.

 

[Stlin]

Theres no way the abutters of the path through Arlington dont throw a shit fit. Red Line trains just below surface would have significant noise and vibration impact on all those households.

I think you would have to deep bore all the way to Arlington to deal with modern political reality.

Eh? I'm not so sure. Based on the plans for the new Red Line hi rail access it's already just under the surface of the Linear Park, and in my years of using it I can safely say I've never noticed a train pass under me.

 

[KCasiglio]

I don't think the shit fit would necessarily be based on a factual understanding of the long term impacts, as these things rarely are.

 

[F-Line to Dudley]

Eh? I'm not so sure. Based on the plans for the new Red Line hi rail access it's already just under the surface of the Linear Park, and in my years of using it I can safely say I've never noticed a train pass under me.

You can hear it in exactly one spot...the emergency exit near Mass Ave. Everywhere else it's silent. That was my daily walking route for the whole decade I lived in North Cambridge.

The only people who are going to throw a shit fit are the ones who throw a shit fit about anything and everything because it gives them something to do. If the better-than-before path were to get its long-requested lighting in the post-construction stitch-up, that'd probably be one of the biggest shit fits thrown ("OMG! Bikes at night!!!"). It doesn't necessarily have to have anything to do with the trains.

 

[WestMedford]

The idea for RLX would be to continue the tunnel from Alewife through Arlington Center and emerge west of Mill Street, then run at-grade to the Heights as it is now (over Grove, Brattle, Forest; under Lowell and Park)? Then the Minuteman would run alongside the at-grade section (like the East Boston greenway path between Orient Heights and Wood Island) and obviously over the cut and cover tunnel? Or is it tunnel all the way? And the yard would be where Arlington Coal & Lumber is now?

Also, how would the expected routing now compare with what was proposed in the 70’s?

 

[393b40]

I don't think the shit fit would necessarily be based on a factual understanding of the long term impacts, as these things rarely are.

This. People's emotions are not always rational.

 

[F-Line to Dudley]

The idea for RLX would be to continue the tunnel from Alewife through Arlington Center and emerge west of Mill Street, then run at-grade to the Heights as it is now (over Grove, Brattle, Forest; under Lowell and Park)? Then the Minuteman would run alongside the at-grade section (like the East Boston greenway path between Orient Heights and Wood Island) and obviously over the cut and cover tunnel? Or is it tunnel all the way? And the yard would be where Arlington Coal & Lumber is now?

Also, how would the expected routing now compare with what was proposed in the 70’s?

The 1975 plan was tunnel all the way. And yes, the yard (which I think was to be above-ground) was going to go on the Arlington Coal & Lumber property.

Most likely they'd keep to the 1975 tunneling plans verbatim. The only real change would be that Arlington Center and Arlington Heights stations wouldn't have the pornographic parking capacities of the very car-brained '75 plan. Both stops would probably have zero parking if done today.


EDIT: The '70s plans had the storage yard @ AH below-ground as longish tail tracks much like Alewife today. Arlington Coal & Lumber property would've been taken for the station itself so it fronted the bus station instead of putting it in Park Ave./Lowell St. triangle. See this post.

 

[themissinglink]

The 1975 plan was tunnel all the way. And yes, the yard (which I think was to be above-ground) was going to go on the Arlington Coal & Lumber property.

Most likely they'd keep to the 1975 tunneling plans verbatim. The only real change would be that Arlington Center and Arlington Heights stations wouldn't have the pornographic parking capacities of the very car-brained '75 plan. Both stops would probably have zero parking if done today.

How much planning for the Lexington section was actually completed before the extension was cut short? Do you know if there were any plans for tunneling in Lexington?

 

[F-Line to Dudley]

How much planning for the Lexington section was actually completed before the extension was cut short? Do you know if there were any plans for tunneling in Lexington?

Very little. Route 128 was proposed in the 1960's, but back then it was going to portal-up on the Fitchburg Line right at Porter and skip straight to Alewife and the Lexington Branch on the surface with no Davis alignment whatsoever. And that was back when the Route 2 expressway extension was going to lay complete waste to North Cambridge. The Route 2 cancellation was what upped the Red extension on the priority pile and got the EIS fast-tracked, but by that point they were only looking at a Phase I to Arlington Heights with Heights-128 punted off to a Phase II that ultimately was never worked on. The early-70's DEIS was when the alignment was narrowed to Davis deep-bore + Davis-Arlington Heights capped cut, and since no conceptual work was undertaken on Phase II there wasn't even any speculation as to whether Heights-128 would be on the surface or below.

 

[F-Line to Dudley]

FEIS Volume I
FEIS Volume II (includes sections on Arlington Center and Arlington Heights stations)