Crazy Transit Pitches

[Wash]

What if we build a tunnel on the Congress St. alignment of NSRL, and then hook it up to the Braintree branch of the red line?

 

[F-Line to Dudley]

What if we build a tunnel on the Congress St. alignment of NSRL, and then hook it up to the Braintree branch of the red line?

The "Red X"...I've written about that at length before. More distant-future the ability to use that alignment for another cross-downtown HRT line may be the saving grace of the state expending so much tankapalooza energy studying that for a gimp NSRL routing.

String together as such:

1. North from Columbia Jct. on the Cabot Yard leads. Filet service in alternating directions across all 4 legs of the "X"...Alewife-Braintree, (new spine)-Ashmont, Alewife-Ashmont, (new spine)-Braintree. Both downtown legs and both branches net equal 3 min. headways from the trading-off at Columbia, which is worth an enormous amount of Quincy growth and growth + extension of Ashmont/Mattapan in addition to the downtown double-up.
2. Divert off the Cabot leads right before the yard-proper by the bridge that overpasses Track 61, portal-under into tunnel underneath Southie Haul Rd. Join into the upper-level Broadway tunnel at A St. that's been mostly disused since 1919, graft on "Broadway Upper" station above the current RL level.
3. Exit the 1919 alignment near Foundry St., tunnel under Cabot Loop on proper alignment to South Station (Atlantic side if NSRL CA/T alignment is taking Dot Ave. side??? I need a map here). Graft "South Station Upper" onto the Dewey Sq. fare lobby. Things will be very spread out here with Silver/Green + existing Red below, NSRL grafted on in very deep cavern towards Dot Ave., this TBD intersect, and the existing surface station + bus terminal...but all behind the same set of Charlie gates. Multiple intersects is why the fare lobby takes up the entirety of the under-street Dewey footprint and has the obvious expansion room that it does.
4. Onto Congress alignment. Intermediate stop at Post Office Square, which has been begging for its own home stop ever since the Green Line reverse-branch from Copley was canceled 105+ years ago.
5. State St. w/ Orange + Blue transfer. Structurally offset on the Congress side of the block, so this already labyrinthine station will get a little bit moreso.
6. Haymarket w/ Orange + Green + NSRL secondary entance transfers. Under the same overhang, but structurally offset. This will be a longer walk to transfers (GL/OL and NSRL concourse) than North Station, so primarily serves local on/offs while being a secondary on transfers.
7. North Station Superstation...graft-on to 2nd level above Orange platforms, across from GL outbound. Instant up/down/across transfers to rapid transit, longish (but shorter than Haymarket) NSRL concourse connector.
8. Double-up OL Charles River tunnel, portal-up by Community College. Can likely add an *excuse-me* "Community College Under" just for being in the neighborhood. Terminate for now on tail tracks underneath the 93 decks, figure out further trajectories later.
9. Further extension is a total choose-your-adventure to any northside ROW simply by quickly ducking under Boston Sand & Gravel and a bunch of BET trackage and choosing which of the 4 mainlines to continue on (may be worth trenching the RL level of CC in a cut below ground-level Orange to facilitate). Some paths will be higher-leverage than others, some will be easier than others when things like grade crossings have to be taken into account...so let's not speculate and just say that for now it's all Phase II and you're stubbing out @ CC Under in the interim.

Final config of the "X":

¹NORTHWEST BRANCH
[Arlington Heights]
[Arlington Center]
Alewife
Davis
Porter (█ + █)
Harvard (█)
Central
Kendall
Charles/MGH (█)
Park St. (█ + >█)
Downtown Crossing (█ + >█)
South Station (█² + █/█ + █ⁿ + █/Am)
Broadway (█²)
Andrew
JFK/UMASS (█²/█³/█⁴ + █ + █)

²NORTHEAST BRANCH
[TBD's!]
Community College (█)
North Station (█ + █ +█ⁿ + █/Am)
Haymarket (█ + █ + █ⁿ)
State Street (█ + █)
Post Office Square
South Station (█¹ + █/█ + █ⁿ + █/Am)
Broadway (█¹)
JFK/UMASS (█¹/█³/█⁴ + █ + █)

³SOUTHWEST BRANCH
JFK/UMASS (█¹/█²/█⁴ + █ + █)
Savin Hill
Fields Corner
Shawmut
Ashmont
[Milton]
[Mattapan]

⁴SOUTHEAST BRANCH
JFK/UMASS (█¹/█²/█³ + █ + █)
[Neponset]
North Quincy
Wollaston
Quincy Center (█)
Quincy Adams
Braintree (█)

 

[Riverside]

^ This, by the way, is probably the best proposal I've read during my time on this board -- certainly the most original. I actually mocked up some maps of this, but can't lay my hands on them right now.

If memory serves, I believe the last time we discussed, the conclusion was that running up the NH Main Line to Woburn was probably the best bet, I think particularly in terms of ease-of-conversion of the ROW to something grade-separated. Aesthetically, I find the idea of running out the Fitchburg to Waltham appealing, particularly given the opportunity to have another transfer at Porter, but there were good reasons why that would be less feasible.

The advantage of what F-Line describes is that hooking in via Cabot and JFK/UMass provides the best-of-both-worlds because you can hook both branches into the Congress Street Subway. As a result, Ashmont and Braintree riders both get maximum frequencies to Downtown, and both maintain the flexible access to Kendall and Harvard.

@Wash I highly recommend reading through the old discussions on this idea -- some great stuff in there.

 

[F-Line to Dudley]

^ This, by the way, is probably the best proposal I've read during my time on this board -- certainly the most original. I actually mocked up some maps of this, but can't lay my hands on them right now.

If memory serves, I believe the last time we discussed, the conclusion was that running up the NH Main Line to Woburn was probably the best bet, I think particularly in terms of ease-of-conversion of the ROW to something grade-separated. Aesthetically, I find the idea of running out the Fitchburg to Waltham appealing, particularly given the opportunity to have another transfer at Porter, but there were good reasons why that would be less feasible.

I kind of go on default assumption that the NH Main is going to be easiest because:

1. the incumbent grade separation
2. the monster ridership projections in Somerville (and echo effects into Medford/Winchester after the North region bus reboot)
3. giving the Green Line a load assist when the Lechmere end projects to host Urban Ring NW off the same alignment as the Union Branch split...Urban Ring NE...Union-Porter and Porter-Watertown extension off the Union Branch...and possibly the branch to Waltham distinct from the branch to Watertown.
4. geographical alignment that fits like a glove with the other legs of the "X" and doesn't introduce pronounced skew like some of the other northside routing options would.

I wouldn't say I personally feel superduper strongly about this. I actually think with how nearly unlimited the options are you need to look at taking a rather long pause at Community College after Phase I to study these potential combos out given that there's a whole lot of demographic noise to sift through...and more than a few potential unintended consequences if you make the wrong pick without accounting for every detail. Rather, on big-picture survey of the northside there's just too many logical line-ups with a Medford/NH Main trajectory that are anywhere from a little bit to a lot messier with any other route, such that any other route has more 'splaining to do as to why its topline bona fides overpower some greater degree of kludging. When all is said and done and studied out that one just looks/sounds/smells a saner prospect to mount than the rest. Figure West Medford crossing pair will be ancient history by this point...zero premium for HRT conversion. Most of the Somerville stations are set up for non-difficult platform lengthening because the ultimate >25-year GLX ridership projections still hedge that it could all go mega- blow out. Medford--unlike Union with both Urban Ring NW and the Watertown/Waltham split--has no future branching opportunities to hedge on forever-LRT and could get bumped at no ill effects to the others...esp. since reverse-transferring is the only way to get from Medford to the other branches anyway (that just takes place 2 stops earlier at North Station in a conversion scenario instead of at Lechmere). And the way the GLX Brickbottom flyover split with Union + carhouse "upstairs" from an underpassing Medford creates grade separation you could thread HRT under/across BET to that spot and slip it right in with minimal changes to the existing environment. Everything just kind of lines up more elegantly that way.

Conversely, going west on the Fitchburg creates major problems for the Union + Urban Ring split onto the Grand Junction, and forces you to choose Waltham or Watertown but never both (Watertown requiring some manner of street-running makes the mode switch lethal...plus the similar "Why?" question we posed re: the Needham Branch's grade crossings with various "Blue-Kenmore swallows D" schemes for making life harder. Fitchburg is probably least appealing. Fitchburg Cutoff? Nope...the branching for two-thirds of GLX then a forking for the trench job to Davis would be hideous. Eastern Route has significant ridership bona fides with Encore/Everett, Chelsea superstation, and Logan as an HRT alternative to the Urban Ring NE. However, that's going to get very dicey at Chelsea River where you have to build rapid transit's first movable span since the Charlestown Bridge stopped swinging on the El instead of shoving the trolleys in a few hundred feet of mixed traffic on the current road bridge to pretty much the same daily schedules. And if HRT they must practically pass up any opportunity to do a Logan Terminals loop because Massport (for all this talk of an APM) has too many resource-pooling reasons to shoot for dual-mode Transitway instead. That's two big feathers in LRT's cap for that routing. Lastly...double-up with Orange to Malden Center if commuter rail goes away? Sure..get rid of the express track and shiv in 1 more track north of Medford St. and you can dual-mode it to MC, one color continues north to Reading, one turns east under the Square to meet up with the Saugus Branch ROW. I actually quite like that one on build feasibility, and because it obeys the "golden rule of branching" in doing it after the last big bus terminal. But...fuuuuuuck...the Saugus Branch. Fat chance convincing the city that killed the Main St. El 100 years ago to take an El build through dense residential backyards all the way to Route 1.

 

[Riverside]

[last paragraph]

And those there are the reasons that I couldn't quite recall from last time.

And I don't disagree. As I said, my reasons for liking the Waltham alignment are largely aesthetic -- there is something nice about the idea of mirroring crossovers at JFK/UMass on one end and Porter on the other. But, for one thing, it's not like Porter, or the surrounding area, is begging for a combined total of trains to Downtown every 90 seconds across the 2 branches... the Medford alignment obviously is much more balanced. And of course I've always been a bit skeptical about the long-term viability of running service all the way to Woburn using the Green Line -- that's a long way and would replace more than half of the Lowell Commuter Rail line, so an HRT option has its appeal.

I mean, if we're really talking crazy crazy transit pitches, you could use this as an excuse to displace the Orange Line north of Community College all together. Send it up to Everett through a subway under Main Street or over the Tobin to Chelsea and beyond. But at that point, we've moved past way crazy pitches into insane pitches -- really only useful for prompting us to consider things from a different perspective (and barely useful even at that).

 

[The EGE]

For a Red X, I much prefer either going to Chelsea and/or Everett. If this is the last change to create a new trunk line through downtown, it doesn't make sense to exclude them. Here's my crayon sketch of a potential route:

Stations at City Square, Bunker Hill/Medford Street, Chelsea, Bellingham Square (GL), [option for Revere Beach Parkway], Everett, Glendale Square, then a couple possibilities for the northern end. You could also do a straighter shot across the Mystic to hit the potential power station redevelopment instead, trading a shorter alignment for missing Chelsea.

 

[Charlie_mta]

View attachment 7176

You could also do a straighter shot across the Mystic to hit the potential power station redevelopment instead, trading a shorter alignment for missing Chelsea.

I'm a big fan of HRT accessing the traditional cores of cities, so I'd vote for the alignment as shown thru downtown Chelsea, which also links to the MBTA commuter rail station.

 

[F-Line to Dudley]

I'm a big fan of HRT accessing the traditional cores of cities, so I'd vote for the alignment as shown thru downtown Chelsea, which also links to the MBTA commuter rail station.

As a "go big" move you could replace the Tobin with a combo road + transit tunnel, but you've definitely got to make up your mind between Chelsea and Everett/Malden. That Urban Ring-duping route switcheroo mid-swing isn't going to work at any functional level.


As before, [something warm-colored] eats CR to Reading + some average-invasiveness Orange 3rd track reconfigs in Medford (way less than if you were trying to reclaim for CR double-track) + 2700 ft. of very mild embankment widening w/ 4th track decks slapped on two bridges lets you side-by-side OL and the Northeast leg of the "X" into Malden Center bus terminal at cut-rate price and guaranteed feasibility. One of the two colors takes on Oak Grove and Reading...the other goes via lower level of MC just underpinning the roadway, then circuits around the block in eastward subway for 3000 ft. under Florence or Pleasant to portal-up onto the Saugus Branch. Run at least as far as US 1 on an El build that goes tall at crossings, minimal/stubby height between close-spaced crossings, and ground-level between long-spaced crossings. Accommodate rail-with-trail below and alongside.

In absolute dollars and sense that checks out superbly on cost, risership catchments, straightforward engineering, and making its double-ups of the OL corridor headways count between the Sullivan/Assembly/Wellington/MC murderer's row bookended by the 2 big bus terminals. The only part that's batshit crazy is expecting residential Malden to swallow a Saugus Branch El that will legit peek into many, many 2nd floor bedroom windows along the way. All-sound build feasibility aside, I just don't have an answer for that local stopper other than forcibly transplanting the most active voting population of Malden. As a Transit Pitch...not Crazy at all. As a Political Pitch?...nope, not 100 years ago and not 100 years from now in that particular city.

 

[Vagabond]

For a Red X, I much prefer either going to Chelsea and/or Everett. If this is the last change to create a new trunk line through downtown, it doesn't make sense to exclude them. Here's my crayon sketch of a potential route:

View attachment 7176

Chelsea and Everett both have the density for HRT. If we know we're crossing water bodies, what is restricting Blue from splitting and following the current SLX route, then following overbuilt Rt 1? Say to https://goo.gl/maps/pL6rA7yUurdxnynf9

 

[F-Line to Dudley]

Chelsea and Everett both have the density for HRT. If we know we're crossing water bodies, what is restricting Blue from splitting and following the current SLX route, then following overbuilt Rt 1? Say to https://goo.gl/maps/pL6rA7yUurdxnynf9

(1) If going by golden rule of branching, never a good idea to be halving frequencies before the biggest bus terminal on the line. Granted, in this case that terminal is unbuilt Lynn, but the logic holds. Lynn was supposed to be included in the Revere Extension build from Day 1 as the capstone; the fact that they've made generations of excuses for not doing it doesn't mean the demand never existed. With that being the entirety of the North Shore's bus supply (and unnaturally choked off of headway for 49 years by the distended Wonderland + 1A/downtown running) true demand will quench 3 min. tippy-top headways in a way that no other service fork possibly could. Because no other potential service fork has the density of terminal transfers...or the exponential higher service gear uncorked by enabling denser last-mile service.

So even in a battle of unbuilt 'hypotheticals', you can't find a branching pair match for Lynn anywhere on the map. Not even Chelsea. The deck stacks too high for full-on mainline frequencies to the North Shore's mega bus terminal, or a punitive apportionment of two-thirds frequencies to the mega terminal and paltry one-third on the comparatively transfer-poor branch which starts aggressively undercutting the value proposition of forking at all.


(2) Environmental practicalities. Now...even while talking some megaproject tag-team of underwater Tobin replacement tube'd out next to an underwater HRT transit berth, there's not a lot of new--or newly scary--climate change considerations with sinking another set of tubes across the Harbor. There's terra firma to anchor to on both the Charlestown and Chelsea ends, and the basic build is not a whole lot different than what's already been done 4 times prior with East Boston Tunnel, Sumner, Callahan, and Ted. It's fucking expensive because it's fucking expensive at baseline...not because it's any order-of-magnitude more difficult to do than it was those 4 other times. You could bring the Northeast "X" through the City Square + Navy Yard alongside 1 and take the flying leap at the new Tobin combo-replacement underwater crossing to implement the biggest unique-routed leg in EGE's map. Figure the scruples behind that big build are all tied up in the greater Tobin Next debate and won't be a solo effort in the slightest.

But you can't really say the same (i.e. "big $$$ isn't a commentary on feasibility") about crossing the marsh when the pants-shitting terrifying flood profile looms as a brand new impediment never before tackled to such severe degree before. As is, BLX-Lynn is going to have to make some hard choices because the "skip everything" Alt. that cuts straight from Revere St. right past Wonderland on a 2000 ft. long trestle across Diamond Creek, over 1A, then over the first slab of marshland to the Eastern Route figures to be an EIS'ing cost meltdown. It's quite likely that the "split the difference" Alt. to Oak Island + curbing along the Little League outfield fence to the scaffolding supply lot is going to be such enormously lower-impact that engaging the kinda-close abutters at the Satter House overrules the all-NIMBY's avoidance "skip everything" because that swamp trestle vs. 50-year flood drainage risk assessment makes it a neutron-bomb level blowout.

I think you're looking at very nearly the same no-practical-go environmental assessment if crossing any of the wider swath of swamp between the Eastern and MA 107. If it's not on the Route 1 ghost ramp grading that whole basin is a practical no-go. And of course...avoiding the basin as no-go means likely forking the branch earlier. In absolute terms that's a bad idea because of #1...but if you have to jump at, say, Suffolk Downs, that's really going to weaken things a ton because the 110, 117, 119 all hit Revere Beach and Beachmont as trans-Revere/Chelsea routes which weakens the ecosystem around a Chelsea-leaning branch.


Now...say that "Reddish-Orange" sideloading to Malden Ctr. does succeed at threading something onto the Saugus Branch and opposite-world Malden history isn't that of an El killer. Between Saugus Branch to 1 and the ghost-ramp grading to Saugus River you might be able to supernode 'em both at Lynn Terminal without incurring an EIS'ing blowout because the berm's already built up by the ancient I-95 extension grading. So for crayon-draw purposes your general route still has an intact trajectory free from sinking under the weight of its own EPA permit via the MC/Saugus Br. tie-in, and with cut-rate construction costs on the Sullivan-MC double-up. Just...again...how many abutters do you have to knife-fight for a variable-height El across Malden grade crossing hell? Build-feasible verily...politically doable narily.

 

[George_Apley]

^ This, by the way, is probably the best proposal I've read during my time on this board -- certainly the most original. I actually mocked up some maps of this, but can't lay my hands on them right now.

Here's a visualization for the 'Red X' I made a while ago.

 

[Charlie_mta]

Here's a visualization for the 'Red X' I made a while ago.

View attachment 7184

I really like that: convert the GLX branch to Medford into a Red Line HRT. I would also extend that HRT line along the existing rail corridor all the way to Woburn Anderson TC. The one huge NIMBY blockage would be Winchester, which may not welcome a Red Line "crime train" (just like Arlington didn't).

 

[George_Apley]

I really like that: convert the GLX branch to Medford into a Red Line HRT. I would also extend that HRT line along the existing rail corridor all the way to Woburn Anderson TC. The one huge NIMBY blockage would be Winchester, which may not welcome a Red Line "crime train" (just like Arlington didn't).

Yeah. Arlington would likely welcome an RLX with open arms in 2020s compared to 1980s. Winchester will probably be happy with RUR frequencies and potentially a GLX that eats Wedgemere and stubs out before the overpass in the town center.

 

[Charlie_mta]

Looking at Google Maps, the ROW narrows to 2 tracks as it approaches the Winchester town line, so HRT conversion would only work through Winchester if freight rail and AMTRAK were rerouted to other rail lines.

 

[George_Apley]

Looking at Google Maps, the ROW narrows to 2 tracks as it approaches the Winchester town line, so HRT conversion would only work through Winchester if freight rail and AMTRAK were rerouted to other rail lines.

The rapid transit tracks would need to duck into a short tunnel under Winchester Center to get past it. No way to widen the viaduct or reroute the locomotive ROW.

 

[Wash]

Yeah. Arlington would likely welcome an RLX with open arms in 2020s compared to 1980s.

In Arlington. Can confirm.

My crazy transit pitch is that the only extension that's really in the cards in the near future is a fully underground one to Arlington Center. The parking situation at Arlington Heights was never really resolved, and the Minuteman Bikeway is too valuable to convert into a transitway without significant (if technically meaningless) community opposition.

 

[F-Line to Dudley]

Looking at Google Maps, the ROW narrows to 2 tracks as it approaches the Winchester town line, so HRT conversion would only work through Winchester if freight rail and AMTRAK were rerouted to other rail lines.

That's from the 1955 grade separation that created the viaducted station (and separated Wedgemere in the process). The line harrowingly used to split smack through the center of the rotary on grade crossings prior to that (see Historic Aerials).

The rapid transit tracks would need to duck into a short tunnel under Winchester Center to get past it. No way to widen the viaduct or reroute the locomotive ROW.

You also have to switch sides because GLX comes up on the westerly side, and north of Winch. Ctr. the freight sidings are all on the west side (but none on the east). So basically when the viaduct starts rapid transit would ramp down into the parking lot, temp-close Laraway Rd. while they cut-and-covered for the rapid transit station site, then slip under the rotary piers to Shore Rd. and incline back up. As you can see by the ped underpass between the high school and the football field it's back to quad-width after the '55 grade separation zone.

On the '45 BTC expansion plan, GLX was supposed to take the Woburn Branch from here...but that's obliterated. The mainline is wide because it used to have crazy quantity of freight customers through Woburn.

 

[F-Line to Dudley]

In Arlington. Can confirm.

My crazy transit pitch is that the only extension that's really in the cards in the near future is a fully underground one to Arlington Center. The parking situation at Arlington Heights was never really resolved, and the Minuteman Bikeway is too valuable to convert into a transitway without significant (if technically meaningless) community opposition.

Tunnel was always to continue to Mill St. then pop up behind the high school. It's so buffered with so much adjacent greenspace and city parks that rail-with-trail the 1 mile to Heights is no issue. Lexington is probably beyond hope, but just get it to Heights first before worrying about them.

 

[F-Line to Dudley]

RE: the "Red X", also keep in mind that the switch-off allows for more flexibility in variable-length "X" legs than the current branching scheme where longer Braintree has to remain in perfect balance with shorter/stop-denser Ashmont. Such that a Mattapan swallow w/ Milton intermediate by Ashmont would practically have to be compensated with a Neponset/Port Norfolk infill on Braintree to keep similar semblance of schedule parity to JFK where 6-on-6 min. headways = 3 min. mainline headway and straight-up alternating Braintree/Ashmont on the 3's.

You have a little more flexibility with the switch off to alternating legs of the "X" because the line is instead being dispatched much more as two independent end-to-enders that just so happen to cross via Columbia grade separation. So for example, a Phase I Congress St. subway to Community College doesn't have to worry excessively about matching Alewife exactly in schedule length. There can be more bunching/gapping within the 3 min. reference headway at the JFK-proper platforms (which can more than handle it @ quad-track w/ crossovers) on the trading-off maneuver than the immaculate balance that has to be retained for today's service. That aids future planning in:

• No excessive urgency to know where you're extending ASAP from the northside portal. As mentioned, the studies really have to be thorough to pick the best choose-your-adventure route so rushing it only invites unintended consequences.
• Being able to plan the past-CC route without having to worry about lengthening past Alewife in tandem for schedule balance. Or vice versa. Woburn is longer than Arlington Heights, for instance...but there's no dependency on how you chunk out the builds if Lexington is still a longshot or Winchester Ctr. is an easier Phase I'ing of the GLX Medford conversion than Anderson. This gets even more important when studying out the other crayon-draw build Alts.
• Southern extension possibilities no longer have to schedule-balance Braintree vs. Ashmont. Braintree basically has no further extension possibilities...it's already hit 128, side room along any of the Old Colony branches is wildly unrealistic, density drops way off in Weymouth or Randolph past that stop. But Ashmont arguably still has life in it past Mattapan as 1/2 mile of stationless subway under River St. anchored to a hard Neponset granite seam opens up the quad-track Fairmount Line grading south of Blue Hill Ave. to Readville for side-by-siding of rapid transit through Hyde Park. And possible continuation to Dedham Center on the grade-separated Dedham Branch ROW. This would make Ashmont significantly longer on the schedule than Braintree because there's some very high-leverage new destinations tapped like HP/Cleary Sq. and Dedham C. But that ceases to be any concern when branch schedules no longer have to be pair-matched at all from a single northern main.
• Run-as-directeds are way easier to plug if there is a (temporary or permanent) jarring mismatch in end-to-end'er lengths. For example, if Phase I of the "X" build has to terminate at North Station or Community College, you may be backfilling some headways through JFK to adjust for the longer travel times on the Alewife leg. So maybe for the (more important) sake of just upholding the 3 min. overall churn the pair-offs feature a higher ratio of one point of origin/destination over another through JFK. It's a kludge in the sense that it's less 'elegant' than a straight faithful ALW-ASH / NS-BRN / ALW-BRN / NS-ASH rotation and some pairings may notice a little 'wobble' in end-to-end frequencies. But in the end everyone's still pounded out to rote "3-min. any-train" frequencies from their local platform as most important consideration. If the base frequency is upheld, then a little necessary schedule-churn 'wobble' on the 4-way pairing rotation is a tradeoff riders will happily take.

In short, for ops it's basically like you have two totally different end-to-end color lines run no different than self-contained linear Orange or Blue...like a "Magenta" line and a "Pink" line. Only because of the properties of Columbia Jct. on one trip "Magenta" is Arlington Heights-Braintree and "Pink" is Woburn-Dedham Center...but on the next trip "Magenta" is "Arlington Heights-Dedham" and "Pink" is "Woburn-Braintree". Still run like self-contained end-to-enders agnostic to needle-threaded timing of branch splits, but almost like the "X" is a spinning wheel of changing 'color' lines instead. It's a very elegant layout on scalability and flexibility.

 

[Wash]

Tunnel was always to continue to Mill St. then pop up behind the high school. It's so buffered with so much adjacent greenspace and city parks that rail-with-trail the 1 mile to Heights is no issue. Lexington is probably beyond hope, but just get it to Heights first before worrying about them.

Those same red line plans depended on the station itself being plopped down on a parcel of land currently occupied by a three-story nursing home. Without tearing the nursing home down, the only way to build any Arlington Heights station on the surface is to take land on the Arlington Coal and Lumber lot. Also, the original study planned for a three-story parking garage and locals were still concerned about people driving in from Lexington. Unless paired with a major bus redesign (and there's no room for bus lanes on Mass Ave west of Arlington Heights), the project is infesible.

All that is to say that RLX-Arlington Center is *far* easier than RLX-Arlington Heights, and offers many of the same benefits.