MBTA Red Line / Blue Line Connector

[stefal]

The problem with that, is I don't think that's actually where the tunnel is, at least if Google Maps is accurate, which places it under Water St. at the intersection with Orange.

Google Maps is not accurate. The Blue Line runs from Govt Center down Court St to State and then down State St. to Aquarium. I think Google Maps just set the main entrance for State @ a headhouse that's not close to the intersection, and in order to show its a transfer stop, they had to alter how the blue line is geographically positioned.

 

[Riverside]

By my reckoning, based on the MBTA neighborhood map for that area, a pedestrian connection from Government Center to State would add about 200 feet to the walk. The longest journey — to State southbound (erstwhile Milk station) would be about 900 feet. That’s about twice as long as the Winter Street Concourse. The existing journey from Devonshire to Milk is about 700-odd feet.

So, it wouldn’t be awful. On the other hand, that would be an awful lot of throughput at Government Center.

 

[JeffDowntown]

I'll disagree there, as I believe that passenger loads that would result on the platforms are something the system wouldn't be able to handle.

Bowdoin gets barely any ridership, so it's irrelevant for that. Gov Center + State split ridership about 50/50.

Agree. The State BL platform gets packed. No way you could transfer all those passengers to Government Center.

Also, the State BL to OL connection is already quite long for Forest Hills trains. Adding the distance to Government Center BL platform to the Forest Hills connection seems pretty objectionable, particularly is you expect people to use the BL to the Airport (we are promoting transit ridership to the Airport, right?).

 

[F-Line to Dudley]

Google Maps is not accurate. The Blue Line runs from Govt Center down Court St to State and then down State St. to Aquarium. I think Google Maps just set the main entrance for State @ a headhouse that's not close to the intersection, and in order to show its a transfer stop, they had to alter how the blue line is geographically positioned.

The tunnels aren't level, either. There's a pretty steep grade on Orange making the whole walkway thing trickier than it looks in 2D (i.e. the walkway can be level, but in places it would be above tunnel level in a utilities layer at added relocation cost/complexity and potentially constricted dimensions).

 

[MjolnirMan]

Google Maps is not accurate. The Blue Line runs from Govt Center down Court St to State and then down State St. to Aquarium. I think Google Maps just set the main entrance for State @ a headhouse that's not close to the intersection, and in order to show its a transfer stop, they had to alter how the blue line is geographically positioned.

It wasn't always like this, and I've submitted corrections multiple times to Google Maps about this to no avail. If you have better luck, godspeed. For some reason they have set the primary station marker for State Street Station to the frequently-closed entrance on Devonshire, rather than, you know, the one at State Street at the State House. Doing this has warped the algorithm responsible for drawing the line. The actual Blue Line tunnel (as anyone who's been in the area knows) crosses the harbor at Long Wharf with the emergency exit "house" at the tip, and continues in a very straight line up past Aquarium up State Street to the station, continues to round Court Street to Scollay Under, and then goes down Cambridge Street to terminate at Bowdoin. Meanwhile the erroneous line actually bypasses Maverick, swings through Christopher Columbus Park, weaves under buildings on Milk Street, and travels under the Old City Hall.

How about this...

I love this. I've previously suggested for many reasons that City Hall Plaza should be totally razed, but the part relevant to your post is the more Crazy Transit Pitch bonus consolidation of the far too many stops on the Orange and Blue lines in the area into a single super-station, to improve travel and minimize walking distance for transfers (all existing entrances could of course still be used for routing to the station). Current conditions are roughly this (yellow indicates the old fountain and a disused tunnel):

Much as you did, I suggested huddling as much as possible towards the Court Street side of the plaza, where yellow represents the approximate area of a multi-level station (in yellow), though I didn't sketch platform locations:

Obviously, the rest of the plaza would be completely demolished and repurposed for something like a series of skyscrapers.

 

[JumboBuc]

Vanshnookenraggen has the best platform map (large pdf), if you're looking for one.

Consolidating the BL platforms at State and Govt Center seems like a ton of work for very little gain.

Blowing through the Bowdoin loop in order to line up with the old path towards the Cambridge St portal seems like a worthwhile trade-off to me. Too bad since density is increasing rapidly there (e.g., the whole Govt Center Garage project) but that stretch of the line is already crowded with State + Govt Center + Bowdoin before Charles/MGH, so redesigning Bowdoin doesn't seem worth it. Maybe as a consolation for losing Bowdoin we could open the Govt Center BL emergency access on Cambridge St as a full headhouse.

 

[Equilibria]

I'll disagree there, as I believe that passenger loads that would result on the platforms are something the system wouldn't be able to handle.

Bowdoin gets barely any ridership, so it's irrelevant for that. Gov Center + State split ridership about 50/50.

I've thought about that since writing it, and you may be right. Of course, that problem is ideally solved by making the platforms wider rather than by making the train stop more often, but I was already into crazy pitch territory .

The important part is that the Red/Blue Connector is not a crazy pitch, nor is the elimination of the redundant Bowdoin in the process.

 

[HenryAlan]

Google Maps is not accurate. The Blue Line runs from Govt Center down Court St to State and then down State St. to Aquarium. I think Google Maps just set the main entrance for State @ a headhouse that's not close to the intersection, and in order to show its a transfer stop, they had to alter how the blue line is geographically positioned.

Okay, that's what I always had thought (the State/Court St. routing), but didn't realize Google just made things up. That said, I don't think this plan makes a lot of sense, as it's a solution in search of a problem. Indeed, it may in fact create problems and at tremendous cost. I'd rather see that money go toward the extension than an unneeded super station.

 

[F-Line to Dudley]

Vanshnookenraggen has the best platform map (large pdf), if you're looking for one.

Consolidating the BL platforms at State and Govt Center seems like a ton of work for very little gain.

Blowing through the Bowdoin loop in order to line up with the old path towards the Cambridge St portal seems like a worthwhile trade-off to me. Too bad since density is increasing rapidly there (e.g., the whole Govt Center Garage project) but that stretch of the line is already crowded with State + Govt Center + Bowdoin before Charles/MGH, so redesigning Bowdoin doesn't seem worth it. Maybe as a consolation for losing Bowdoin we could open the Govt Center BL emergency access on Cambridge St as a full headhouse.

The reason for plowing through the loop to realign is that even a half-trip through the extremely tight curvature of the existing infrastructure is such a speed restriction that it makes balancing IB-OB headways from Charles very difficult. Covering the distance would take markedly different time each direction because of the different IB vs. OB curvatures, and that introduces enough inefficiency to require offsets elsewhere on storage space and for load-balancing the line if/when the Lynn extension is built. Plus the Bowdoin platforms themselves would have to be structurally modded to fit 6 cars on both sides, and the station retrofitted for ADA. All told it's a lot of cost chew just for getting Bowdoin up to snuff as a low-use 'tweener station, plus taking on the inconvenient ops quirk of the asynchronous trip through the half-loop. For the same money as modding the station you can just straighten the alignment to keep traffic management dirt simple, invite longer/higher-capacity cars on a future order by whacking the ruling curve on the line, and upgrade the GC emergency exit into that full-service Blue-only entrance that they were originally supposed to build before that got chopped from the renovation budget. All told, the package of upsides you get from demolishing Bowdoin for the straight alignment outslugs the alternative handily. When Suffolk Downs explodes and Lynn is a major ridership pipe, you'll want those longer cars that seat 45 instead of 35. You'll want bi-directional headways that can shrink to same as Orange level instead of having to leave a forever extra minute's padding as compensation for the Bowdoin half-loop asynchronicity. And you'll want all of those things on the capacity & ops side if you ever envision it eventually going Charles-Kenmore as a Storrow Drive trade-in.

 

[whighlander]

I'm with you. They missed the chance to render Bowdoin truly redundant when they made the northern BL platform access emergency-only. Nonetheless, the Blue Line has an absurd number of stops Downtown - 0.6 miles between the Marriott Long Wharf and Bowdoin Square, 4 sets of platforms. Honestly, the T should be looking into eliminating State as a platform stop as well. Rename the State OL stop "Government Center" and connect it to the rest of the station with pedestrian tunnels.

Super Bad Idea -- State's Orange Line platform provides an ideal connection to DTX Orange Line Platform -- very short amount of tunneling is needed

Make the connection NOW and then plan for an upgrade that will make DTX the true Master Station

From one entry point on Washington St a T commuter would have access to :

• All Green Line Trains at Park via the existing pedestrian tunnel
• All Orange Line Trains at DTX [existing Platforms]
• All Red Line Trains {except Mattapan Line] at DTX or Park depending on crowding, etc.
• All Blue Line Trains at State via the new pedestrian tunnel and existing pedestrian connections at State
• All Washington St Silver Line Service at DTX or Park
• All other Silver Line Service via one stop on the Red Line to South Station

After a period of time to try this out -- the next phase is moving walkways to expedite service
Final phase of the DTX Master Station Project -- provide a connector with moving walkways from the Summer St end of the Red Line platform to a new Head House near to Winthrop Square

The T and most transit systems are way way behind airports in the use of moving walkways -- which now can climb and descend and go around curves

 

[F-Line to Dudley]

Super Bad Idea -- State's Orange Line platform provides an ideal connection to DTX Orange Line Platform -- very short amount of tunneling is needed

Make the connection NOW and then plan for an upgrade that will make DTX the true Master Station

From one entry point on Washington St a T commuter would have access to :

• All Green Line Trains at Park via the existing pedestrian tunnel
• All Orange Line Trains at DTX [existing Platforms]
• All Red Line Trains {except Mattapan Line] at DTX or Park depending on crowding, etc.
• All Blue Line Trains at State via the new pedestrian tunnel and existing pedestrian connections at State
• All Washington St Silver Line Service at DTX or Park
• All other Silver Line Service via one stop on the Red Line to South Station

After a period of time to try this out -- the next phase is moving walkways to expedite service
Final phase of the DTX Master Station Project -- provide a connector with moving walkways from the Summer St end of the Red Line platform to a new Head House near to Winthrop Square

The T and most transit systems are way way behind airports in the use of moving walkways -- which now can climb and descend and go around curves

Let's please not say the word "moving walkways" like it's some sort of magic accessibility pixie dust for the excess walking distance until the T is shown capable of keeping a mission-critical escalator in-service for more than a week at a time. There is nothing superbadder than the moving walkway that never moves because it's always blocked off with traffic cones. If that's the veneer needed to keep the ADA at-bay, moving-parts uptime becomes an immediate legal concern for the whole dubious Master Station concept.

At a more practical level it is very unlikely that all parts of these 21st-century graft-on concourses to century-old subway tunnels will afford anywhere close to the width allowances of the lucky repurposing we got out of the Winter Street Concourse subway tunnel bore. That's not a reliable dimensional reference point for a proposal that hasn't been engineering-scoped at any level. You need very wide concourses to stick a pair of single-direction ADA-compliant moving walkways next to a bidirectional ADA-compliant floor. Unlike the geometric near-perfection of a pre-planned airport terminal connecting concourse or above/below-street city skyway where pretty much all extant examples are uniform-dimension (and where Winter St. serves up a too-optimistic local example), you can't count on this ped tunnel network being doable without pinch points. It is by its very nature a quick-and-dirty retrofit where we have to take what the subterranean spaghetti layers give us for space. Probabilities are overwhelming that it'll be far from uniform, and if having to bore through an inconvenient utility layer means choosing (A) lots of pain and cost blowouts for uniform dimensions, or (B) accepting a single-point pinch as a compromise...you better make sure the $$$ allocated to that answer leaves you in ADA compliance if you're also taking some ped accessibility away by having further-spaced stations. It's not hard to accommodate an inconvenient pinch as no big deal when it's just a static floor between the existing accessible stations adding purely net-gain access. It is very hard when Jetsons Shit walkway tech is what you're betting on to duct-tape the Master Station concept together around the accessibility demerits of the longer walking distance around consolidated stations. Because even the transit system that's GOOD at repairing its elevators/escalators can't physically achieve unblemished pure 100% machine uptime.

ADA seeks accessibility as near to 100% of the time as humanly possible, and that means no moving parts when a simple ramp will do and having no-moving-parts backups to the moving-parts primary access when possible. The problem with nearly all wild-and-kwaaaazy technological kludges to a public services accessibility mandate is that the kludge is almost always chasing lower odds of real-world reliability than the mandate requires. If the underground moving walkway-a-thon is the accessibility prerequisite for downtown station consolidation, it's not going to work if construction hits a pinch point that narrows the concourse. Because then when a moving walkway is out-of-service 0.001%, 0.1%, 1%, or 10% of the time...it's non-compliant and whatever squished-width flooring is left alongside it isn't enough to back it up on the accessibility mandate. Whereas if you just made static concourses between the existing all-accessible stations you probably can do it all-accessible width without squeezing blood from stone on the underground urban spaghetti infrastructure allowances, and be able to sanely bargain around compromises to make sure it gets built at all with available funds.

I think the walkways are definitely buildable, though nowhere near a first priority as duh-obvious load-spreaders like Red-Blue or targeting individual station egresses that are longstanding festering sores on constipated ped movements. Study them, and if there's no nightmare blockers take what they can grab for space and get it done because it'll all be substantially net-positive. But I can't take this Master Station scheme seriously in any form where the ped concourses are the accessibility glue that allows for closing other stations. That's too much higher a standard to reach for when needing to compensate for displaced accessibility, and the dimensional/throughput requirements of the ped tunnels have to get a lot closer to perfect than "grab-and-go" in that scenario vs. as a pure augmentation. If the distances are long enough that you need Jetsons Shit tech to overcompensate...forget it. That's asking for too much perfection on both the available dimensions and technological reliabilities when the real-world probabilities say perfection's never practically going to be achievable to that degree.

 

[ulrichomega]

Vanshnookenraggen has the best platform map (large pdf), if you're looking for one.

Consolidating the BL platforms at State and Govt Center seems like a ton of work for very little gain.

Blowing through the Bowdoin loop in order to line up with the old path towards the Cambridge St portal seems like a worthwhile trade-off to me. Too bad since density is increasing rapidly there (e.g., the whole Govt Center Garage project) but that stretch of the line is already crowded with State + Govt Center + Bowdoin before Charles/MGH, so redesigning Bowdoin doesn't seem worth it. Maybe as a consolation for losing Bowdoin we could open the Govt Center BL emergency access on Cambridge St as a full headhouse.

My issue with blowing up Bowdoin and not replacing it with anything is that you then create the longest stretch of no-station anywhere downtown other than Park-Charles, and given how isolated Charles already is, why are we isolating it even more? It's a half mile between GC and Charles. A better solution, especially to help crowding at adjacent stations, would be to just rebuild a simple station under Cambridge St at roughly Staniford St. (assuming the grades work out to make that possible).

 

[millerm277]

My issue with blowing up Bowdoin and not replacing it with anything is that you then create the longest stretch of no-station anywhere downtown other than Park-Charles, and given how isolated Charles already is, why are we isolating it even more? It's a half mile between GC and Charles. A better solution, especially to help crowding at adjacent stations, would be to just rebuild a simple station under Cambridge St at roughly Staniford St. (assuming the grades work out to make that possible).

The emergency exit for the Blue Line gets you ~250ft closer to the current Bowdoin entrance, though. If that's reopened, I think you're only around 600ft from the current Bowdoin entrance.

Not that I have any idea what the design ideas are like, but assuming they aren't sticking the Blue Line platforms in the river, there's likely going to be an opportunity to build Blue Line entrances/headhouses for the new Charles Station that are a few hundred feet closer down the street (and don't require crossing Charles Circle on foot).

If you do both of those things, it would mitigate that to a degree.

 

[Equilibria]

My issue with blowing up Bowdoin and not replacing it with anything is that you then create the longest stretch of no-station anywhere downtown other than Park-Charles, and given how isolated Charles already is, why are we isolating it even more? It's a half mile between GC and Charles. A better solution, especially to help crowding at adjacent stations, would be to just rebuild a simple station under Cambridge St at roughly Staniford St. (assuming the grades work out to make that possible).

I don't think Bowdoin does much for that isolation today, though. It's not a station for Cambridge Street but for a different edge of City Hall Plaza (and the Government Center complex).

If we assumed headhouses 500 feet apart (as is the case at Alewife, for example), the eastern entrance would be at Anderson Street, hopefully integrated into one of the new MGH buildings. That's a ways down the street. No idea what they do on the other side of Cambridge, FWIW. They'd need to buy out a store and be able to punch through the basement - that's never been attempted in modern Boston, AFAIK.

 

[ulrichomega]

The emergency exit for the Blue Line gets you ~250ft closer to the current Bowdoin entrance, though. If that's reopened, I think you're only around 600ft from the current Bowdoin entrance.

Not that I have any idea what the design ideas are like, but assuming they aren't sticking the Blue Line platforms in the river, there's likely going to be an opportunity to build Blue Line entrances/headhouses for the new Charles Station that are a few hundred feet closer down the street (and don't require crossing Charles Circle on foot).

If you do both of those things, it would mitigate that to a degree.

I'll grant that the Charles end is going to be a lot closer than the current position of the Charles station (assuming the new headhouses actually get built), but I was measuring from what I think are the emergency exits. I say think because I'm honestly not sure where they actually are.

From main headhouse to main headhouse the distance is 3000ft. If you lop off some at either end for smaller headhouses at the opposite ends of the platforms, that nets you about 500 ft. That still leaves 2500 feet between your two stations. And that's as the crow flies, not actual walking. It's about a five minute walk from the GC emergency exits to the Staniford St, where I'd put a NeoBowdoin station. That's not a lot of time saved, but it's something. A new Bowdoin station right in the middle of the two would also give the Blue line comparable stop spacing to the other lines in downtown (at least between those stations), so I'm not sure why it's considered too close. At the very least, I'd expect the tunnel to be built with provisions for a future station.

I'll grant that Bowdoin station probably isn't worth the cost, but I also don't agree that it would be unreasonable to build.

 

[Equilibria]

Standard 1/4-mile walkshed for an Anderson St. entrance nets you essentially all of the Cambridge Street corridor. Note that the equivalent circle for Government Center overlaps with this one.

Stations are expensive, and decel-dwell-accel takes time. That's the case against.

 

[ulrichomega]

Standard 1/4-mile walkshed for an Anderson St. entrance nets you essentially all of the Cambridge Street corridor. Note that the equivalent circle for Government Center overlaps with this one.

Stations are expensive, and decel-dwell-accel takes time. That's the case against.

I don't disagree with the cost-benefit analysis, but this same logic points to shutting down Chinatown as well. It's well within the catchment of Tufts/DTX and adds travel time to Orange Line travellers. It's not a matter of drawing circles on a map and pointing out what's within them, it's a matter of looking at projected usage of the station and measuring how much time you're saving the people getting off there versus how much time you're wasting for people going through.

EDIT: An analysis that I don't think the Bowdoin station would do well on at the current time, but if development in that area picks up I think it would do well eventually. Not building the station means you have large swathes of the West End pretty far from a station by downtown terms.

 

[JeffDowntown]

Standard 1/4-mile walkshed for an Anderson St. entrance nets you essentially all of the Cambridge Street corridor. Note that the equivalent circle for Government Center overlaps with this one.

Stations are expensive, and decel-dwell-accel takes time. That's the case against.

View attachment 195

At what point does the 1/4 mile catchment logic break down (asking legitimately)?

The Green Line and the Orange Line have numerous stations within 1/4 mile of each other, and I don't hear cries to shut down one of the lines (or eliminate many of the "duplicative" stations) for efficiency.

Government Center/State
Park/DTC
Boylston/Chinatown
Copley/Back Bay Station
Symphony/Mass Ave
Northeastern & MFA/Ruggles

 

[JumboBuc]

^ Equilibria's whole efficiency point applies to one line. It often doesn't make sense to space stops along a line really close to each other, because the benefits you get from shorter walks are offset by the accumulated time lost to decel/dwell/accel and its associated congestion.

None of this applies across separate independent lines. Riders on the Green Line, for example, don't have to wait when the Orange Line is decelerating/dwelling/accelerating. And if Symphony station were closed, for example, GL riders couldn't just wait a stop and get off at Mass Ave instead. That's not how any of this works...

All that being said, the biggest loser from a Bowdoin closure would be the (booming) Bulfinch Triangle / West End area S and W of the Garden. That's currently in the Blue Line catchment area of Bowdoin, but would lose that coverage with Bowdoin closed.

 

[Arlington]

The emergency exit for the Blue Line gets you ~250ft closer to the current Bowdoin entrance, though. If that's reopened, I think you're only around 600ft from the current Bowdoin entrance.

...upgrade the GC emergency exit into that full-service Blue-only entrance that they were originally supposed to build before that got chopped from the renovation budget. All told, the package of upsides you get from demolishing Bowdoin for the straight alignment outslugs the alternative handily.

Yes. GC Emergency Exit is located here.(https://goo.gl/maps/UJmRi6bUZasZRX7B6). Entrances on the "Bowdoinside" of both MGH and GC are a better solution than keeping a curve-crippled Bowdoin. And if we're crazy-wrong, in 40 years, you can come back and do an infill on its site. When they straighten things out and eliminate Bowdoin they should put it in a place that doesn't rule out a Future Straight Bowdoin.

Depending on what AFC 2.0 looks like, you could probably push the front doors /canopy to the headhouse another 50 feet closer to Bowdoin/Sudbury/Bullfinch Place for a psychological win.

And, yes, build/provision MGH Blue as a two-ended platform