Green Line Reconfiguration

[vanshnookenraggen]

Huh? Green to Green to Green? Why? Say you're on a train from BU and you want to go to the Seaport. Take the train to Boylston. Get off. Board a Seaport-bound train. Voila. Two-seat ride.

This assumes there is a north side to Seaport service and I really doubt this will or should happen. Lets say for sake of example that the Huntington Ext is built via the Bay Village station. That gives you the D,E and F trains coming up on the outer tracks and then through to GC. At Park St you then have to cut back both B and C trains AND if we want to throw in and A train to Harvard. Not terrible but at rush hour at least one of those is going to have to be extended to GC or North Station. That's 4 busy lines through GC, doable but it is as tight as service is today.

So now you want to add this reverse service from the north to the seaport and somehow fit it through this tight window. But wait, you already have some Back Bay Green Line service running to South Station which is going to take pressure off of Red-Green transfers at Park St. So instead of trying to ram an additional route through GC why not just have the small amount of people that need to get from the north side to the Seaport change at Park St where there is now more room (for passengers) and save the hassle.

This is why I see a Boylston-Seaport route as superior. It has less moving parts and connects more of the GL branches in one place. As with my argument for a new tunnel under the Charles to Harvard, I think the benefit will justify the cost.

 

[George_Apley]

^ A fully upgraded system, the likes of which we've discussed here and elsewhere, ought to be able more lines through the Central Subway than we currently have. But given your opinion on the matter, I see your point.

 

[vanshnookenraggen]

Most of what we have discussed is everything south of Park St along the Central Subway. The Park-GC bottleneck is a real killer for more service north of Park St. Even just having a second set of tracks to GC would do wonders.

It's fun to think about but had the Post Office Sq branch ever been built this would have given up the second set of tracks we'd need to get north of Park St. The POS branch originally terminated at POS but would have most likely been extended up Devonshire and Congress Sts to Adams Sq and beyond. Such an alignment would have balanced the load of the downtown transfers better as the POS branch would have had connections to DTX and State St (whatever those stations used to be called).

Map

Unfortunately today with the Seaport being built out and Adams Sq totally demolished that routing won't be an option.

 

[F-Line to Dudley]

There could be a new new light rail/pedestrian bridge instead. I see using the existing bridge with street running along JFK St a non-starter. It's already bad on the 66, imagine what traffic will be like when the Allston campus starts to grow.

Maybe, but you've got to be realistic here. If you want grade separation at all, that branch is going to get a hell of a lot more expensive to build. And it will get kicked much further down the priority pile. And now preserving the ROW through Allston becomes dicier because Harvard is not going to keep that reservation reserved forever if there's no action plan or timetable for using it.

Does 1000 ft., no stops, 2 traffic lights from a right turn at the northernmost corner of Ohiri Field to that Memorial Dr. corner entrance to the JFK Park really matter enough to bloat the cost, put it off, and risk having nothing ever? Because that's what the pearl-clutching about bridge gets you.

I have a really hard time seeing the doomsday scenario in that when it's 100% grade separation everywhere but that thousand feet. The branch-headway schedule can be predicated around absorbing the uncertainty on that 1000 ft.

Also...consider how much the asinine ex-MDC traffic signaling and road layouts pointlessly congest that intersection. How could this intersection possibly still be without full protected left cycles in every direction in the year 2015? How much more pain and suffering is that causing? Hell...there's room on the west side of the intersection both JFK directions to lane-shift to full-on left turn lanes.

We don't even know what the real traffic loads here because DCR signaling throughout the whole Charles Basin is a wholly arbitrary exercise in masochism.

 

[F-Line to Dudley]

I've also given the Kenmore loop that F-Line designed more thought that while I still think a slingshot service that flips back down the D line is too much, it still may be worthwhile to somehow connect the existing loop to the B line. This would give any UR service a proper terminal. It may be that to keep headways on track you'd need to build a 4 track extension of the Comm Ave subway to BU Bridge but since that subway isn't even built yet that might be totally feasible. Basically connect the new outer tracks coming in from Comm Ave to the C/D junction at Kenmore and loop any UR trains there. Have the 4 tracks go to BU Central, possibly having a pocket track built, so that you can stage the trains better. Also if the Huntington Ave extension is built and most D line trains are rerouted then you'd be able to fit more UR trains on the outer/C line tracks at Kenmore.

The current loop is not configured to ever interface with the B. Structurally it just can't be reworked where it currently is and B vs. C/D have already split before entering the platforms so re-interfacing from the west won't work. That was the reason I proposed the duck-under loop east of the station in the cavernous footprint where Beacon and Comm Ave. are splitting off. It can be as shallow as the upper loop is a mere 1 ft. over the station roof and not too expensive to build, but that's the only place you can do it. (Note: This would NOT foul any future Blue Line/Riverbank "Kenmore Under" because that's clipping at an angle from the Beacon side and this loop is basically straddling the Kenmore St./Comm Ave. intersection on that side at shallower depth than the Riverbank Subway would be going).


If the engineering is thumbs-up, you might want to do that whether there are any plans to use it for more than a terminating loop. It's not like there has to be a boomerang. I was only positing that as the lone construction-feasible possibility for actual thru Cambridge-Longwood service per the T's own Urban Ring plan...because a cut-over anywhere east of St. Mary's St. is physically and financially impossible to an extreme, the Amory St./I-695 routing is physically and financially impossible to an extreme, and Park Dr.--while physically reasonable for the dig--has so many problems with the D interface and flood mitigation the engineers are going to have a real problem with it. And I wasn't gonna do it unless the old loop could be decommissioned to put passing tracks on the wall side so UR trains only stopped on the B platforms and avoided any intermixing with mainline traffic.

So, really, the boomerang is just the last hope for the T's own UR trajectory. And that's the whole point of the thinkpiece. It may well be infeasible. And may well not be needed at all, because note that the T's own UR study made some far-leaping assumptions about one-seat ridership crossing between quadrants of the Ring to justify the overly complex moving parts of that build. Further study may not serve up a compelling reason for run-thrus being non-optional when each NW/NE/SW/SE quadrant of the Ring has a super-node to tie into. It may very well be that step-off/step-on transfers pooled at the Kenmore/Dudley/Transitway/Lechmere super-nodes cover the need within a rounding error of equally well. That all needs further study. They were trying awfully hard to justify the existence of that cross-Brookline dig. Those numbers need to be refreshed to make sure they weren't lightly cooked the first time around.

Any which way, the mobility to Longwood is stratospherically better and every 66 rider needing to get between the Harvard and LMA pairs is going to get there faster and more frequently with a Kenmore step-on/step-off than they do taking the slow bus to hell. We're splitting hairs about degrees of difference. Everything isn't terrible and the Ring doesn't fall apart if run-thrus can only happen on halves of the Ring.

 

[F-Line to Dudley]

This assumes there is a north side to Seaport service and I really doubt this will or should happen. Lets say for sake of example that the Huntington Ext is built via the Bay Village station. That gives you the D,E and F trains coming up on the outer tracks and then through to GC. At Park St you then have to cut back both B and C trains AND if we want to throw in and A train to Harvard. Not terrible but at rush hour at least one of those is going to have to be extended to GC or North Station. That's 4 busy lines through GC, doable but it is as tight as service is today.

So now you want to add this reverse service from the north to the seaport and somehow fit it through this tight window. But wait, you already have some Back Bay Green Line service running to South Station which is going to take pressure off of Red-Green transfers at Park St. So instead of trying to ram an additional route through GC why not just have the small amount of people that need to get from the north side to the Seaport change at Park St where there is now more room (for passengers) and save the hassle.

This is why I see a Boylston-Seaport route as superior. It has less moving parts and connects more of the GL branches in one place. As with my argument for a new tunnel under the Charles to Harvard, I think the benefit will justify the cost.

^This is also important to consider. The system as it is today with never-changing end-to-end schedules and inbound termini is not how the Green Line worked through much of its history. The art of effective load-balancing short-turns was completely abandoned and now they're so inflexible they don't even remember how they did it 30 years ago on the same exact system. And in the MTA days when there was still a skeletal grouping of surviving streetcars through the 50's alt routing and branch run-thrus mixed up the service as regular practice. It was a lot like what we're proposing for the N-S Rail Link...a blender of service. Something light rail is ideally suited for.

You can't understate the importance of the interconnections. Or assume that Bostonians won't adapt like New Yorkers have to trains that don't always run on the same route every single headway to reach a same destination. This was old hat in Boston for 60+ years. Hell...it was old hat in 1985 when Arborway went Arborway-Park all day and simultaneous and overlapping Heath-Lechmere service ran on the 9-to-5. As is, T and T riders can't even fathom the low-hanging-fruit concepts of:
-- Building a short-turn pocket track at Harvard Ave. to load-manage the B.
-- Running C's thru from Cleveland Circle to Boston College
-- Short-turning at Reservoir.
-- Running thru from Reservoir to BC.
-- Chucking down some street-running tracks from the corner of S. Huntington to Pearl St. and BV and having some very limited BV-turning E bootstraps (more headways than Heath Loop's limited storage allows), or even continuing to Reservoir on that unused capacity.

I mean, that's something $10M in cumulative construction can accomplish ALL OF right now if they wanted.


A reimagining like this is not going to involve destination pairs poured in concrete. You have north, west, and south branches joined at nodes. You have:
-- Brookline Village run-thrus on to 2 different downtown subways.
-- Brookline Village pingback for 'circuit' service between the 2 downtown subways.
-- Brickbottom Jct. run-thrus from Union/Grand Junction to Lechmere, Chelsea to Lechmere, or Chelsea to Union/Grand Junction.
-- BU Bridge Jct. for Grand Junction-Central Subway, Central Subway-Harvard, Grand Junction-Harvard
-- South End Jct. for the big tie-in to downtown, or running thru Back Bay-Seaport, or doing MULTIPLE alt. route legs using any 2 of the system's multi-directional junctions.
-- Copley Jct. is still there for service disruptions.
-- Park loop, GC loop (both directions), and North Station are still there as turnbacks. South End Jct. would create a de facto around-the-block loop for any Tufts short-turns. The mid-line carhouses--Reservoir and Brickbottom--still allow for Reservoir-turning (or BV-turning, since the car supply isn't far away) or Lechmere-turning.


And this is all without building the Kenmore boomerang.


There is almost no limit to Crazy Destination Pair Pitches you can draw up with these options. Obviously there will be majority-prevailing patterns equivalent to the current letter-line destination pairs. But it'll be back to the future on a grand scale with short-turns and alt. routings once again becoming a significant part of the picture. And significant amount of the rush hour load-balancing (e.g. a Seaport-North Station short-turn acting as the rapid transit N-S Link) fine-tuning the loads. And all the newly gained line transfer nodes are going to reduce the crowding at Park and GC (and NS to lesser extent) because those are no longer the be-all/end-all points where everything must transfer.

That's the crux of the reimaging. It's all fluid. You can draw whatever service patterns you want on the canvas to narrow-target specific demand patterns when they're needed, how often they're needed, for how many hours they're needed. And this will not be a concept Bostonians have any trouble adjusting to. This was the public transit rule not the exception for their ancestors who rode BERy, the MTA, and the early MBTA.

 

[Shepard]

I just want to put it out there: all these "full build" systems seem to serve Watertown and/or Waltham via Porter and Somerville. I get the reasons of course. But I think that service pattern is fairly ridiculous and won't generate anywhere as much ridership as a straight shot somehow through Allston.

 

[FK4]

^ yeah Ive never been much for restoration of anything on the watertown branch. it swings way north before coming way back down toward the river. what might work better is a streetcar running down western ave... but if we have a harvard line, there wont be enough room to accomodate one more line there, i dont think....


SPEAKING OF WHICH
there is some massive clearance soon-to-be construction I saw at the western and northern end of arsenal st today - appeared to obliterate even more of the rail ROW. hopefully not, could be at least a good bike route.

 

[F-Line to Dudley]

I just want to put it out there: all these "full build" systems seem to serve Watertown and/or Waltham via Porter and Somerville. I get the reasons of course. But I think that service pattern is fairly ridiculous and won't generate anywhere as much ridership as a straight shot somehow through Allston.

It's the only route with grade separation that doesn't require hugely-expensive tunneling. Tunneling the B straight up Brighton Ave. through to N. Beacon St. or under the B&A starts adding more billion-dollar appendages with big Charles Basin flood mitigation issues to plot vs. sea level rise.

Unfortunately there were no direct-connecting historical rail ROW's serving up a north-south leg because of the historical private RR competition. And the Newton city line was the dividing line between private streetcar companies. BERy went no further west than Watertown Sq. where the 57, 71, and 70 meet, and the Oak Sq.-Watertown stretch of the ex- A Line required trackage rights sharing with Middlesex & Boston Street Railway between Newton Corner and Watertown. The only such instance of 'foreign' travel on BERy, for sake of completing a circuit to Watertown Carhouse. The sharp divide in bus route orientation at Corner and H2O Sq. is the legacy of that, since Middlesex & Boston stayed independent as a bus company until the T was formed in '64 and bought their routes. That whole end of the Yellow Line system grew up apart as if the proverbial Route 128 dividing line between inner 'burbs and outer 'burbs ran straight down Galen St. And since that was the fringe, there weren't a lot of wide boulevards built serving up a reservation like there was on a lot of streets that acted as BERy 'mainlines' for diverging routes.

It's a tough stitch job when all the growth late-19th to prewar-20th c. got baked in around that divide. You have to fashion this out of the paths we were given to work with. And that unfortunately doesn't favor a path through Allston. It never did.

 

[vanshnookenraggen]

A Waltham>Watertown>Allston>Central Sq route would actually be a great place for BRT. Not that the roads are wide enough for a dedicated ROW but certainly an express bus would be a step up. It isn't a corridor that could support the cost of rail rapid transit but improving the already popular bus routes is a good first step. I'm not against BRT but rather I'm against using it as a band aid when rail rapid transit is preferable. I feel like the Silver Line sunk any chances to properly utilize BRT in Boston given the way the T forced used it as a catch all for Roxbury, the South End, and SBW. This should be in another thread but it's something that should be looked at as a way of improving existing heavily used bus lines.

 

[F-Line to Dudley]

A Waltham>Watertown>Allston>Central Sq route would actually be a great place for BRT. Not that the roads are wide enough for a dedicated ROW but certainly an express bus would be a step up. It isn't a corridor that could support the cost of rail rapid transit but improving the already popular bus routes is a good first step. I'm not against BRT but rather I'm against using it as a band aid when rail rapid transit is preferable. I feel like the Silver Line sunk any chances to properly utilize BRT in Boston given the way the T forced used it as a catch all for Roxbury, the South End, and SBW. This should be in another thread but it's something that should be looked at as a way of improving existing heavily used bus lines.

That and whoo-boy would the Indigo Line at real 15 min. headways and fare equitability to Riverside on the Worcester Line and Waltham on the Fitchburg Line really help.

-- Riverside w/Newton Corner infill could consolidate all those Pike express buses.

-- Extend the 71 to loop at Corner. Would take only 1/2 mile of TT wire hooked up to the ex- A Line feed still live under the street as a B<-->TT interconnection. Maybe get some articulated TT's. String up a couple wire 'passing sidings' en route, then introduce "SL71" express BRT service from Harvard. In addition to carrying heavy local ridership, that BRT pattern could also divert some conventional commuter rail riders (esp. in the A.M.) bound for Harvard, especially the ones who work at Mt. Auburn Hospital or any of the med office buildings out there. 2003 PMT pegged that capital cost at $1.5M for the infrastructure and 1 extra bus, with +600 daily increase in transit riders not currently taking public transit (that figure NOT making any assumptions about a commuter rail transfer).

-- Bank some freed-up equipment and slots to fashion some stiffer-headway N-S routes. The Pike express buses no longer needed. The 553, 554, 556, 558 out of Waltham are mostly stand-ins for nonexistent train service at the 3 Newton intermediates. There's resources available here for brisk headways on a N-S/cross-Newton BRT with some route consolidation, room for a little more local bus variety on under-served areas, and definitely a lot more cross-Allston possibilities.

-- If you're hedging on future rapid transit considerations the expunging of the Needham Line off of the NEC and commuter rail serves up some obvious BRT nodes. The 59 would truncate at Newton Highlands (the Riverside-Needham Jct. branch transfer station) with that Green branch, and the 52 would be be peeled 1 block off Baker St. in West Roxbury into the Orange Line station's busway. I see some sort of Waltham<-->Newtonville<-->Newton Highlands<-->W. Rox BRT corridor possibilities fashioned out of the 556, 59, and 52 routing. Or an easterly flank more faithful to the 52's route into Watertown.



A lot of these routes were streetcars back in the day. The north-south routes well-represented on the Middlesex & Boston system. Moody St. was the north-south 'mainline' that forked onto River St. and Lexington St. (553, 554, 558). Washington St. and Main St. were the E-W mainlines...553, 554, and the 70. With the big transfers into the BERy system at H2O Sq. and Corner. The 59 was theirs, pretty much on the same routing. So look where the trolley suburbs grew out. These north-south bus routes surviving from the M&B system all seem to intersect east-west RR lines: Fitchburg RR @ Waltham, Fitchburg RR Watertown Branch @ H2O Sq., B&A @ the Newtons, B&A Highland Branch @ Riverside and Newton Highlands, Needham Branch, and the E-W mainline out of W. Rox and Needham Jct. All seem to pool at the transfer nodes with the BERy district which also clustered at the RR stations on the B&A and Watertown Branch of the Fitchburg RR. And all seem to follow a distinct mainline + branching pattern out of Waltham and Watertown to do it.

Follow the development of the streetcar suburbs. The reimagined Green Line (and it's Indigo stand-in on the B&A) is what used to be high-frequency local RR service, on an east-west orientation. Those are the ROW's we are left to play with. The north-south routes binding Waltham and Newton together were the streetcar mainlines. Those are the mixed-traffic boulevards wide enough for BRT to play with. It was a hub<-->transfer<-->spoke system of interconnections when it was built, and these very neighborhoods grew up around that spine.

Don't fight the history. This pattern of movement worked for a very long time, from the horsecar era until the early bustitution era. And really didn't come unglued until the 50's when the RR's went splat and MassDOT started eminent domaining residential property for pending expressways. In other words, it worked that way for more decades than it didn't work that way. There's a pretty natural fit here for transfers from rapid transit to streamlined bus routes that don't require us to warp this GL system map with one-seats everywhere. There never were one-seats everywhere. That was a mentality the MBTA concocted for itself as one of its well-worn excuses for not doing obvious things.

 

[davem]

I agree that Watertown via Porter is really roundabout. While I think a line there would eventually make sense to distribute loads, I do not think it should be the first build, since it makes no sense to get downtown that way.

It's the only route with grade separation that doesn't require hugely-expensive tunneling. Tunneling the B straight up Brighton Ave. through to N. Beacon St. or under the B&A starts adding more billion-dollar appendages with big Charles Basin flood mitigation issues to plot vs. sea level rise.

Unfortunately there were no direct-connecting historical rail ROW's serving up a north-south leg because of the historical private RR competition. And the Newton city line was the dividing line between private streetcar companies. BERy went no further west than Watertown Sq. where the 57, 71, and 70 meet, and the Oak Sq.-Watertown stretch of the ex- A Line required trackage rights sharing with Middlesex & Boston Street Railway between Newton Corner and Watertown. The only such instance of 'foreign' travel on BERy, for sake of completing a circuit to Watertown Carhouse. The sharp divide in bus route orientation at Corner and H2O Sq. is the legacy of that, since Middlesex & Boston stayed independent as a bus company until the T was formed in '64 and bought their routes. That whole end of the Yellow Line system grew up apart as if the proverbial Route 128 dividing line between inner 'burbs and outer 'burbs ran straight down Galen St. And since that was the fringe, there weren't a lot of wide boulevards built serving up a reservation like there was on a lot of streets that acted as BERy 'mainlines' for diverging routes.

It's a tough stitch job when all the growth late-19th to prewar-20th c. got baked in around that divide. You have to fashion this out of the paths we were given to work with. And that unfortunately doesn't favor a path through Allston. It never did.

There are a ton of options that don't require all that much tunneling to get to Watertown from Allston, if you split off at the BU Bridge:

Click for annotated map

If it's going to be converted to heavy rail eventually (blue line), I favor the path through the middle of the Arsenal Mall.

If it's going to always be a trolley, then running on Talcott Ave is a lot cheaper.

Either way, the only tunnel is a cut-and-cover job to get to the other side of the Pike. Then a new bridge across the Charles, either reusing the historic location of the old N. Beacon St bridge, or a new one using the embankment where the stock yards used to be.

You could also not cross the Charles at all by running along side the Pike, then take advantage of space freed up by the lane-drop on Nonantum Road to Watertown Yard. Only issue there is it's a dead-end, no future extension to Waltham.

 

[George_Apley]

I agree that Watertown via Porter is really roundabout. While I think a line there would eventually make sense to distribute loads, I do not think it should be the first build, since it makes no sense to get downtown that way.



There are a ton of options that don't require all that much tunneling to get to Watertown from Allston, if you split off at the BU Bridge:

Click for annotated map


You could also not cross the Charles at all by running along side the Pike, then take advantage of space freed up by the lane-drop on Nonantum Road to Watertown Yard. Only issue there is it's a dead-end, no future extension to Waltham.

What future extension to Waltham? I don't think the Watertown Branch is any good between Watertown and Waltham unless it's grade-separated.

 

[Shepard]

The Talcott routing is rather brilliant. You can eat a lot of the redundant Birmingham Parkway for the ROW adjacent the pike, after the short tunnel you picture. And, you have excellent riverfront TOD potential where the IHOP/McDs/Staples/Martignettis is now. Cutting up to Arsenal street over Talcott never occurred to me, but it's so obvious when you see it mapped.

 

[davem]

The Talcott routing is rather brilliant. You can eat a lot of the redundant Birmingham Parkway for the ROW adjacent the pike, after the short tunnel you picture. And, you have excellent riverfront TOD potential where the IHOP/McDs/Staples/Martignettis is now. Cutting up to Arsenal street over Talcott never occurred to me, but it's so obvious when you see it mapped.

Iterative process FTW!

I've always done the routing through the Arsenal Mall, but to better debate F-Line I took the time to see if there were other options, and there are a ton.

I also really like the Talcott Ave routing, since it would open that closed street for some use (the gates could be automated to keep cars out), and would be very low impact (probably would just have to remove the parallel parking). It's also a beautiful little street for some picturesque street-running, AND you can get a station in to serve the Market Street area, plus the TOD potential you mentioned. Permitting for a new Charles River crossing adjacent to the N. Beacon St bridge would also not be as difficult as other options, since there was a historic bridge there before the current one was built.

Spitballing, but I think it could probably all be done for under 100M.

 

[vanshnookenraggen]

If it's going to be converted to heavy rail eventually (blue line), I favor the path through the middle of the Arsenal Mall.

If it's going to always be a trolley, then running on Talcott Ave is a lot cheaper.

These are the most realistic options.

The biggest hurdle I see with a routing like this is that it takes priority away from the B line. If you look at the bus routes from Watertown they mostly go to Harvard or Central. The 57 still goes to Kenmore but most of that traffic isn't from Watertown and is picked up through Brighton. This means that you still have most of the demand of Brighton>Downtown via the B line.

Lets say to build out the Watertown line. Is there are Harvard Line too that branches off at West Station? That's two more lines feeding into the Central Subway and even if there was a Huntington Ext to take the load off that still leaves the branches going out of Kenmore at a lower headways to get all the branches to fit. This means that the C line is going to have to be run as a shuttle to Kenmore and that is going to piss a lot of people off.

Keep in mind that the demand off the C line is going to be higher than any demand from a Watertown or Harvard branch for a long time to come. This is why I think BRT is a better option especially given current demand.

Also I'd like to have a better idea of where the Watertown>Cambridge commuters are going. If their destination is downtown then the Green Line would work. But if they are working in Cambridge, Harvard or Kendall area, then a route that runs along the GJ would work better.

 

[Shepard]

Van - not sure if the station layout of a hypothetical BU Bridge would allow this, but it could be that this new A routing might routed over the Grand Junction - which, boom, maintains the historical connection of Watertown and Cambridge. And then, at BU Bridge, A line riders can change for B line service through the central subway.

Again, I'm not sure there's a station layout that can easily allow this, but that's what I'd aim for.

 

[vanshnookenraggen]

Van - not sure if the station layout of a hypothetical BU Bridge would allow this, but it could be that this new A routing might routed over the Grand Junction - which, boom, maintains the historical connection of Watertown and Cambridge. And then, at BU Bridge, A line riders can change for B line service through the central subway.

There can't be any station at BU Bridge if you are going to have branches. What could be done is rerouting the B line up to the West Station, making West a 4 track transfer station like Kenmore, so that Harvard and B trains run via Central Subway and Watertown trains run up the GJ. The issue then is where do Watertown trains go? If they go via Green Line then you'd loop them at Gov't Center.

This then brings me back to one of my early Blue Line proposals which would extend the BL to Cambridge via a new tunnel to Binney St where it would follow the GJ to West Station.

While way more expensive then a simple Green Line route it do cover all the bases:
- Red-Blue connected.
- Lower Red Line congestion given alternative Cambridge service (although this isn't a huge reduction)
- Back Bay Bypass + connection to Green Line in Allston which could scoop up a lot of B line riders.
- Simplified Green Line extension to West Station + faster Green Line service by eliminating street running service through BU.
- Connecting Watertown and Allston commuters to "downtown" Cambridge and Gov't Center faster than a bus>Red Line transfer.

Obviously the cost is greater with tunneling but look at what the Blue Line would do for the GJ that Green Line propositions don't. Green Line/UR routings supposed that the GJ would be totally converted to light rail and all CR opps would have to be transferred to other facilities (new, billion dollar facilities). Since the Blue Line along GJ would require tunneling, at least below grade along Vassar St, this gives you the opportunity to build a 3 track line with space for CR movements that removed grade crossings. There is space along the line for 3 tracks, especially if you are going to tunnel under the Red Line, but it would require a new rail bridge where the existing BU Bridge is... but keep in mind any new rapid transit expansion over the GJ is going to require a new bridge. This is a much more expensive proposition BUT it has so many benefits by eliminating grade crossings and still allowing CR movements (and thus not requiring new CR facilities) that the benefit would justify the cost.

The Blue Line would also be a better balance than an additional Green Line branch. More GL branches from the west would only cause more congestion in the Central Subway. Any riders using the BL to Watertown would be getting off either in Cambridge or Boston with few (non-Logan bound) riders staying on to Eastie or Revere.

Blue Line via the Back Bay and D line would take pressure off the Green Line but it wouldn't really serve anyone new, thus requiring new Green Line branches and thus making more congestion in the Central Subway. Running it via the GJ would serve new areas, reduce congestion, and speed travel from the west to downtown Boston.

Additionally, and this is really thinking far ahead, if there was a one seat ride from Cambridge/MIT to Lynn via both Blue Line extensions then I can totally see Lynn becoming a hot spot for workers and students priced out of Cambridge. That would really help grow the economy even more than a simple BL extension to Lynn alone.

Map.

Edit: I'm going to x-post this to Crazy Transit so any Blue Line discussions can happen there.

 

[F-Line to Dudley]

I agree that Watertown via Porter is really roundabout. While I think a line there would eventually make sense to distribute loads, I do not think it should be the first build, since it makes no sense to get downtown that way.

This isn't the Crazy Transit Pitches thread. Tunneling money gets allocated to the trunks that distribute downtown load. We can't be wasting it on branchlines or else major chunks of the system can't be built with all the big-money diversions to pet branch projects. We're already facing that dilemma with the Harvard Branch and whither 1000 ft. of street-running + the JFK front lawn or hold out 20 years for the money for a Charles crossing and risk Harvard cannibalizing the path through Allston.

Watertown goes considerably lower on the list. If it takes tunneling to get there from Allston, then it doesn't get built at all. Just restore the entire A Line streetcar if it's that important. We want to get something built. When it's a non- load-bearing branch, find the surface routing that gets it built or else it won't get built.

There are a ton of options that don't require all that much tunneling to get to Watertown from Allston, if you split off at the BU Bridge:

Click for annotated map

If it's going to be converted to heavy rail eventually (blue line), I favor the path through the middle of the Arsenal Mall.

It's not, because you can't eliminate the Main St. grade crossing on the Grand Junction. That's a a forever-LRT, and so is the subway out to BU Bridge if it's going to interface with the GJ.

If it's going to always be a trolley, then running on Talcott Ave is a lot cheaper.

I can get behind this if you are forking as-streetcar off Union Sq. and up N. Beacon the whole way. But that probably means you are 1:1 trading in Oak Sq. for this, since it's one too many branches to have both. I think the density and destinations out to Oak outslug Watertown, but I can be sold on this if there's a demographic argument.

Sold on it as 100% surface. It's a lesser branch; it doesn't make the cut if there's digging involved.

Either way, the only tunnel is a cut-and-cover job to get to the other side of the Pike. Then a new bridge across the Charles, either reusing the historic location of the old N. Beacon St bridge, or a new one using the embankment where the stock yards used to be.

Your surface jaunt on the B&A isn't going to work because the addition of a Pike EB breakdown lane planned with the interchange project, West Station, New Balance, the commuter rail layover yard planned for Beacon Park, and the passing track planned spanning these two CR stations (needed for juggling Indigoes, Worcesters, and Amtraks hopping over each other here) eats up all the room. Would-be tunnel has to be half-mile longer. 2-1/2 times the distance, 2-1/2 times the cost. If that didn't cost too much before, it definitely does now.

If you have to go this way, you're better off pulling off the Harvard Branch in the middle of Harvard-Allston, slipping under the Cambridge St. underpass, and just making Lincoln St. a one-way with a trolley reservation shoved off on the Pike side. Slip under the Market St. overpass (may have to hollow it out on that side, but that's an old span well overdue for replacement). Then decommission Birmingham Pkwy. to get on N. Beacon. All-surface and grade separated till you're at the rotary (overpass SFR on the east side to keep it short) and can slip off the grass onto the existing Charles bridge. No new Charles bridges, please...if you build a new Charles Basin crossing the EIS'ing is costlier and there's a wonderful extra "DCR tax" lathered on top and however many more power-struggling bureaucrats that entails trying to get their friends paid to design-build the prettiest signature crossing.

You could also not cross the Charles at all by running along side the Pike, then take advantage of space freed up by the lane-drop on Nonantum Road to Watertown Yard. Only issue there is it's a dead-end, no future extension to Waltham.

Not enough ridership served hugging Nonantum all the way. There isn't a direct shot on the street grid to Newton Corner the way Nonantum is on the bottom of that steep hill, so it's abdicating 90% of the potential ridership there despite the close crow-flies distance. That's going to create NIMBY's on the side streets because it's there...but it's not usefully there, and those who have to use it are going to be wandering aimlessly past their houses on 1 of 5 side streets to work their way down the hill. If it's not going right to Galen it creates more problems than it solves by getting close...but so indirectly close.

If you're going to miss Corner, might as well miss it cleanly and stay bolted to N. Beacon.


Also...that section of Nonantum floods. Expect there to be a lot of "E trains turning at Brigham Circle" days on the calendar for this branch when Charles Basin is feeling all bloated and crampy.



Waltham is never ever ever ever going to get served out of Watertown. Just count how many bad-angle grade crossings there are on the Watertown Branch. It would take 20 minutes and get FUBAR'ed by a trolley-vs.-car collision twice a week. Waltham is only reachable bolted to the Fitchburg Line.

 

[Matthew]

BTW, MassDOT is quietly moving plans forward to do deck replacement on the Market Street overpass.