Crazy Transit Pitches

(Also, not for nothing, but if that 170' limit is non-negotiable and the need to provide ~170' of vertical clearance over the water is also non-negotiable, that pretty much rules out a light rail bridge.)

Those lift statistics are interesting though. If you could build high vertical-lift bridge high enough to clear the tugboats, most of the problem would seem to be eliminated with less than one opening per day. It's probably expensive though, which is where the Massport dollars could come in handy. To my point the other day about building Elevated on already-blighted areas, you could probably snake across 1A like you have even with the height restrictions to a station where the police station is like the original APM concept had.
 
Just as a cable-car related aside, I have been thinking about where one might be practical. It feels like there should be some route possible that makes a useful transport link while also feeding into the more touristy appeal of a cable car, like some combination of Jeffries Point, Seaport, Long Wharf, and Charlestown Navy Yard. Something over the Charles might also be possible but I don't think that would really be useful, more just neat. (I'm also not sure if the airspace above the Charles is heavily used for helicopters/light aircraft like the Hudson or Thames are in NY/London respectively.)
I was thinking about this more, and realized that the corridors I sketched out for Charles River Ferry service might actually fit the bill.

1704135578000.png


Some possible ideas might be:
  • North Station <> Kendall
    • less keen on this one, there are a number of less expensive ways to do this
  • Kendall <> Back Bay
    • if you are willing to run a cable car further inland in Back Bay (EDIT: which, to be clear, I realize people would lose their minds over) such that it's truly an OSR between Back Bay station and Kendall, this could be interesting, as this particular corridor is very very hard to serve with either the current or future infrastructure
  • Harvard <> BU
    • not shown on the map above, but as I discuss in the linked post, the river is actually the most direct route between the two
 
How exactly are you going to make a cable car route that goes from the Airport to Chelsea "touristy". Chelsea and touristy usually don't go into the same sentence.
Different cable car, I was referring to my half-serious pitch of a cross-harbor tourist cable car between Seaport and Eastie.
 
Happy new year everyone! This is certainly a very interesting line of discussions.

Goal of cable cars: transit/parking vs. tourism?
I think @TheRatmeister brought up a curious point of building a cable car route that has tourism appeals, though to some extent they were conflating it with the original intent that started the discussion (i.e. connections to remote parking and transit facilities, hence to Chelsea). But how about we separate the two goals altogether, and build a dedicated "line" to a destination that actually has tourism value, but not just that:
1704141968265.png


All points west of Terminal A indicate potential tower locations. All of them are within 1970 ft, which @Riverside found to be the standard maximum distance between towers. Maverick may or may not have a station (I doubt there's enough space for one).

To be clear: Battery Wharf is clearly not the best insertion point downtown, but it's not intended to be the terminal. The reason I chose it is that it gives the shortest distance for harbor crossing: the corners of Battery Wharf and LoPresti Park that I indicated are only 1530 ft apart. (This also alleviates some of the clearance issues.)

From Battery Wharf, there are two ways you can continue within downtown:
  • South to Aquarium
    • Direct airport-downtown connection with rapid transit
      • Thus, can also be used by Boston residents heading to airport, and airport employees
      • Probably the least useful downtown corner and the most redundant rapid transit connection, but still
    • Connects to a major tourist destination
    • Likely offers better aerial view than the next option
    • If you're feeling really ambitious, can extend even further to South Station via Greenway (which would be quite a ride)
  • West to North Station
    • Regional Rail connection and better rapid transit connection
      • With NSRL, this may even absorb most or all of RR-airport traffic, reducing the need for SL1
    • But connects to less ideal parts of downtown Boston
    • Can potentially continue west to Kendall like @Riverside suggested
    • Can potentially be rerouted via Charlestown Navy Yard rather than Battery Wharf, like @TheRatmeister suggested
Of course, you will need to deal with the political challenges of running a cable car above the neighborhoods in Jeffries Point. Another concern with using cable cars for airport transportation is dwell time, as @TheRatmeister mentioned. Because most (modern/efficient) cable car systems are always moving, it can be hard for people with luggage to board and alight in time. (As a side note, systems that do not come to a full stop can still have intermediate stations.)
 
Last edited:
Vertical clearance for Chelsea Creek
Back to the original topic of a Chelsea Creek crossing for any mode (cable car, LRT, etc).

Unless I'm mistaken, I think the limiting factor along the river may not actually be the Chelsea St bridge (175'), but actually the McArdle bridge further west. Wikipedia suggests McArdle only has a clearance of 157 ft when open, though I'm not sure about its accuracy due to it being a bascule bridge. So while the contradiction between the 175' Chelase St clearance and 170' Logan restriction is interesting, at the moment I'm not too worried with a bridge that doesn't reach the full 175'.

However, I am more concerned about neighborhood impacts of such a bridge for LRT. The Tobin Bridge, which has a clearance of only 135 ft, already has significant impacts to Charlestown an Chelsea, basically segregating Navy Yard and Admiral's Hill from the rest of the neighborhoods. From the discussions on Tobin Bridge grades last time, it looks like the maximum grade for highways is 4% (maybe 5%). (FYI, for rapid transit grades: Most info I can find online for railways say 4%, NYC's heavy rail system has the steepest grade being 5.5%, and Riverside said LRT can handle 7%.)

This means if the Chelsea St bridge is rebuilt to support both cars and rapid transit, with a vertical clearance of 170 ft, the lead needs to be 4250 ft for 4% grade - almost getting to Bellingham Square station:
1704144508936.png


(A Tobin-equivalent clearance of 135' would mean 3375' lead, which starts from between Broadway and Box District station. An LRT-only bridge with 7% grade and 170' clearance needs 2428', starting a bit east of Box District near the MWRA building. 7% and 135' needs 1928', which starts at Marlborough St and avoids most of the neighborhoods.)

While I guess a good thing is that the northeast side of this ROW is nothing to worry about, looks like this will still have significant impacts to residents in east Chelsea around the Box District station's area. However, this is turning out a bit better than I thought. And it will probably be much more manageable with a cable car.

So this seems to disagree with @TheRatmeister's opinion that anything other than a tunnel is ruled out: it's technically feasible, the question lies more in politics. However, I think a new bridge will likely have to be for transit (and bike trail) only, as the rail ROW doesn't have the width to support both transit and cars. This points to keeping Chelsea St bridge untouched for cars, and building an adjacent bridge dedicated to transit.

(On the other hand, I do think any above-water crossing not using this ROW is out of question due to neighborhood impacts, even though they would be closer to density.)


Miscellaneous
  • Kendall <> Back Bay
    • if you are willing to run a cable car further inland in Back Bay (EDIT: which, to be clear, I realize people would lose their minds over) such that it's truly an OSR between Back Bay station and Kendall, this could be interesting, as this particular corridor is very very hard to serve with either the current or future infrastructure
This is actually an interesting connection that I've been thinking about lately.
  • There's a great argument for treating Back Bay as part of downtown. In that case, northside Red Line probably has the worst possible connection to Back Bay systemwide.
  • Hot take: This is also the best way to improve trips served by the T1 bus (from a demand-only standpoint). Not a route along Mass Ave, and not a route further west. My anecdotal observation is that many T1 riders seem to be going to Back Bay (and not, or at least in addition to, transferring to the Green Line further west), so a more direct connection to the heart of Back Bay area, rather than on the periphery like Hynes station, would really help.
  • And of course, an additional connection to regional rail and Amtrak.
I had been crayoning a rapid transit route like this - you may call this a "mini ring":

1704146053220.png


This may not look like an obvious "Urban Ring" at first, but it's really a hybrid between a circumferential route and a "radial" route centered at Back Bay. Short and sweet. (You can extend it further into Charlestown and South Boston, of course.)

The obvious problem is... $$$$$$. Not only does most of the line need to be deep bored (C&C under Third St, Dartmouth St, E Berkeley St etc may all be technically feasible, but between utility relocation, landfill, and political challenges due to impacts to residents, I doubt it), but it involves a new Charles River crossing (that has to be a tunnel unlike BU Bridge), abutting tall and/or historic buildings in Back Bay... etc.

But yeah, back to your point, a cable car between Kendall and Back Bay may be a very intriguing way of serving the main purpose of this line while potentially having a much lower cost.

(Edit: On second thought, I'd combine the Copley and Back Bay stations into one. The platform can be placed on Dartmouth St between St James Ave and Stuart St, which avoids the Pike and most historical buildings in this area (Boston Public Library, Old South Church, Trinity Church). Short pedestrian tunnels connect the Pink Line station to OL Back Bay (370') and GL Copley (310' for GL outbound). This reduces cost and travel time, although may increase traffic at the station. It also offers an in-station transfer between GL and OL/GLR, which is valuable in a GL Reconfiguration world.)
 
Last edited:
I had been crayoning a rapid transit route like this - you may call this a "mini ring":

View attachment 46315

This may not look like an obvious "Urban Ring" at first, but it's really a hybrid between a circumferential route and a "radial" route centered at Back Bay. Short and sweet. (You can extend it further into Charlestown and South Boston, of course.)
I like the route. I would extend it to the north via a new combo road/transit Tobin Bridge replacement, extending the line to Chelsea and possibly Everett. Also, at its southern section, I'd run it instead down Dedham St and Malden St to cross over the Widett Circle area to serve future development there, and thrn curve up to the RL Broadway Station.
 
Last edited:
I like the route. I would extend it to the north via a new combo road/transit Tobin Bridge replacement, extending the line to Chelsea and possibly Everett.
The only reason why I didn't include it was that in my "ultimate fantasy plan", I have another route serve Chelsea via Tobin Bridge: the Red X, via Congress St downtown. I think it offers a much more direct connection to other lines, all things considered.

But yeah, in a world where only one of these two downtown routes can be built (and even that is still too ambitious or maybe God Mode), whatever gets built should be sent to Chelsea. If two lines get built, the other can still go from Community College via Rutherford Ave and Broadway to Everett, Glendale, etc.

(Though, thinking about it again, maybe I should have the two fantasy routes cross at Community College to offer a transfer to each other. Otherwise, the Everett-Back Bay route won't connect to the Chelsea-Congress St route at all.)

Also, at its southern section, I'd run it instead down Dedham St and Malden St to cross over the Widett Circle area to serve future development there, and thrn curve up to the RL Broadway Station.
Do we know if anything is planned to be developed at Widett Circle? Last time I heard of it was MBTA planning on eminant domain to build a rail yard there.
 
FC
Do we know if anything is planned to be developed at Widett Circle? Last time I heard of it was MBTA planning on eminant domain to build a rail yard there.
I believe you are correct. It's somewhat wishful thinking on my part that Widett Circle could be developed into medium/high rise residential served by a rapid transit station.
 
FC

I believe you are correct. It's somewhat wishful thinking on my part that Widett Circle could be developed into medium/high rise residential served by a rapid transit station.
Do we know if anything is planned to be developed at Widett Circle? Last time I heard of it was MBTA planning on eminant domain to build a rail yard there.
From what I understand the MBTA has already acquired the land. They have left open the possibility of air rights development, so I wouldn't count it out just yet. Hudson Yards in NYC is a high rise residential area on top of a rail yard, it can be done.
 
Last edited:
Vertical clearance for Chelsea Creek
Back to the original topic of a Chelsea Creek crossing for any mode (cable car, LRT, etc).

Unless I'm mistaken, I think the limiting factor along the river may not actually be the Chelsea St bridge (175'), but actually the McArdle bridge further west. Wikipedia suggests McArdle only has a clearance of 157 ft when open, though I'm not sure about its accuracy due to it being a bascule bridge. So while the contradiction between the 175' Chelase St clearance and 170' Logan restriction is interesting, at the moment I'm not too worried with a bridge that doesn't reach the full 175'.

However, I am more concerned about neighborhood impacts of such a bridge for LRT. The Tobin Bridge, which has a clearance of only 135 ft, already has significant impacts to Charlestown an Chelsea, basically segregating Navy Yard and Admiral's Hill from the rest of the neighborhoods. From the discussions on Tobin Bridge grades last time, it looks like the maximum grade for highways is 4% (maybe 5%). (FYI, for rapid transit grades: Most info I can find online for railways say 4%, NYC's heavy rail system has the steepest grade being 5.5%, and Riverside said LRT can handle 7%.)

This means if the Chelsea St bridge is rebuilt to support both cars and rapid transit, with a vertical clearance of 170 ft, the lead needs to be 4250 ft for 4% grade - almost getting to Bellingham Square station:
View attachment 46314

(A Tobin-equivalent clearance of 135' would mean 3375' lead, which starts from between Broadway and Box District station. An LRT-only bridge with 7% grade and 170' clearance needs 2428', starting a bit east of Box District near the MWRA building. 7% and 135' needs 1928', which starts at Marlborough St and avoids most of the neighborhoods.)

While I guess a good thing is that the northeast side of this ROW is nothing to worry about, looks like this will still have significant impacts to residents in east Chelsea around the Box District station's area. However, this is turning out a bit better than I thought. And it will probably be much more manageable with a cable car.

So this seems to disagree with @TheRatmeister's opinion that anything other than a tunnel is ruled out: it's technically feasible, the question lies more in politics. However, I think a new bridge will likely have to be for transit (and bike trail) only, as the rail ROW doesn't have the width to support both transit and cars. This points to keeping Chelsea St bridge untouched for cars, and building an adjacent bridge dedicated to transit.

(On the other hand, I do think any above-water crossing not using this ROW is out of question due to neighborhood impacts, even though they would be closer to density.)


Miscellaneous

This is actually an interesting connection that I've been thinking about lately.
  • There's a great argument for treating Back Bay as part of downtown. In that case, northside Red Line probably has the worst possible connection to Back Bay systemwide.
  • Hot take: This is also the best way to improve trips served by the T1 bus (from a demand-only standpoint). Not a route along Mass Ave, and not a route further west. My anecdotal observation is that many T1 riders seem to be going to Back Bay (and not, or at least in addition to, transferring to the Green Line further west), so a more direct connection to the heart of Back Bay area, rather than on the periphery like Hynes station, would really help.
  • And of course, an additional connection to regional rail and Amtrak.
I had been crayoning a rapid transit route like this - you may call this a "mini ring":

View attachment 46315

This may not look like an obvious "Urban Ring" at first, but it's really a hybrid between a circumferential route and a "radial" route centered at Back Bay. Short and sweet. (You can extend it further into Charlestown and South Boston, of course.)

The obvious problem is... $$$$$$. Not only does most of the line need to be deep bored (C&C under Third St, Dartmouth St, E Berkeley St etc may all be technically feasible, but between utility relocation, landfill, and political challenges due to impacts to residents, I doubt it), but it involves a new Charles River crossing (that has to be a tunnel unlike BU Bridge), abutting tall and/or historic buildings in Back Bay... etc.

But yeah, back to your point, a cable car between Kendall and Back Bay may be a very intriguing way of serving the main purpose of this line while potentially having a much lower cost.

(Edit: On second thought, I'd combine the Copley and Back Bay stations into one. The platform can be placed on Dartmouth St between St James Ave and Stuart St, which avoids the Pike and most historical buildings in this area (Boston Public Library, Old South Church, Trinity Church). Short pedestrian tunnels connect the Pink Line station to OL Back Bay (370') and GL Copley (310' for GL outbound). This reduces cost and travel time, although may increase traffic at the station. It also offers an in-station transfer between GL and OL/GLR, which is valuable in a GL Reconfiguration world.)

Can someone explain what the difference between a cable car and an automated people mover(APM) is in the context of this conversation?

I am getting lost in the terminology here. I’ve always understood a cable car to be more like a tram that is pulled by a cable, like the San Francisco Cable Cars.

Sorry for the uneducated question. I hope it isn’t taken the wrong way!
 
Can someone explain what the difference between a cable car and an automated people mover(APM) is in the context of this conversation?

I am getting lost in the terminology here. I’ve always understood a cable car to be more like a tram that is pulled by a cable, like the San Francisco Cable Cars.

Sorry for the uneducated question. I hope it isn’t taken the wrong way!
"Cable car" refers to a billion different things which makes it quite unhelpful as a term, unfortunately. In general, (I can only speak for myself, it's possible others have also gotten a different impression) In this discussion, "Cable Car" refers to one of these, also called an aerial/urban gondola or aerial tram. (Still confusing) "Cable car" can also refer to cable trams or a cable railway, used as you said in San Francisco or, even more confusingly, in some airport people-mover systems such as at Oakland Airport, although for the purposes of this discussion to latter simply fall into the category of "Automated People Movers", (APMs) which can use a variety of different technologies. Many are more like guided buses, some are cable hauled, the one at JFK is actually quite similar to the Vancouver Skytrain, and there are probably more types I missed.

I think "Light Rail" or "LRT" also got thrown around a bit, which (From what I understand) has mainly been in reference to a direct connection to the airport terminals as part of an urban ring/UR adjacent scheme.

TL;DR

"Cable car" refers to this
"APM" refers to this (or similar)
"Light rail" refers to this
 
Can someone explain what the difference between a cable car and an automated people mover(APM) is in the context of this conversation?

I am getting lost in the terminology here. I’ve always understood a cable car to be more like a tram that is pulled by a cable, like the San Francisco Cable Cars.

Sorry for the uneducated question. I hope it isn’t taken the wrong way!
No worries. The "cable cars" that we refer to in this conversation should technically be called gondola lifts, which consists of many small vehicles supported by a continuously moving cable hanging from above, with no rails underneath.

What you linked to be "cable cars" are basically trams running on rails similar to LRT. Looks like they're typically referred to as "cable trams" outside of North America, whereas the more international description of "cable car" is probably the ones in the sky.

(To make things even more confusing, there's a third thing called "aerial trams", which look like gondola lifts but operate differently. While gondolas have a single, circuitous, continuously moving cable, aerial trams typically have one or two parallel end-to-end cables shuttling the car back and forth. The car can therefore have higher capacity, but limited in frequency and intermediate stops - think of a shuttle railway without crossovers to turn the trains around.)

One advantage of gondolas is that they can operate wherever cables can be hung between towers, which can be far apart and/or differ in altitude, without building a surface ROW underneath. This makes them attractive for hilly terrains and river crossings (the latter is relevant in the context of Logan), as well as potentially being a low-cost form of transportation with less disruptions on the surface. Additionally, they are also much more frequent than most other means of transit.

Their downsides are much lower capacities per vehicle, typically in single digits; and the need for cars to be constantly moving, which isn't ideal for passengers with disability needs or bulky items. For both reasons, whether they make sense for Logan Airport here remains the question.
 
What you linked to be "cable cars" are basically trams running on rails similar to LRT. Looks like they're typically referred to as "cable trams" outside of North America, whereas the more international description of "cable car" is probably the ones in the sky.
I believe that a cable tram is distinct from modern LRT in that the former is propelled by "grabbing onto" an externally-powered cable that is running underneath the street, whereas the latter has an engine on board.

In that sense, cable trams and gondolas are both "cable cars" whereas LRT is not. However, unlike gondolas, all remaining cable trams are legacy/historical--nobody would make a new cable tram as part of a modern LRT network.
 
Apologies for not being clearer in my terminology! Yeah, @TheRatmeister, @Teban54, and @kdmc are all correct in their interpretations.
Their downsides are much lower capacities per vehicle, typically in single digits; and the need for cars to be constantly moving, which isn't ideal for passengers with disability needs or bulky items. For both reasons, whether they make sense for Logan Airport here remains the question.
Yeah, this is where my lack of knowledge is. I was envisioning something where the cars stop entirely, but the image in my mind was of something like London's; sure enough, while their cabs do slow down a huge amount, it looks like they remain in constant motion.

Ironically, I had figured they'd have a system like (street-running) cable cars, where the cab "unclamps" from the cable when halting in order to decelerate and stop. But I guess probably they don't want to make it physically possible for a cab to disconnect from the cable, lest a failure occur midair. (Still seems like it should be a solvable problem, but...)

It sounds like we would need an aerial tram in order to provide a viable passenger experience. But, it also sounds like aerial trams would be too slow and too infrequent to provide a viable service.

So. This idea is probably DOA.
 
Apologies for not being clearer in my terminology! Yeah, @TheRatmeister, @Teban54, and @kdmc are all correct in their interpretations.

Yeah, this is where my lack of knowledge is. I was envisioning something where the cars stop entirely, but the image in my mind was of something like London's; sure enough, while their cabs do slow down a huge amount, it looks like they remain in constant motion.

Ironically, I had figured they'd have a system like (street-running) cable cars, where the cab "unclamps" from the cable when halting in order to decelerate and stop. But I guess probably they don't want to make it physically possible for a cab to disconnect from the cable, lest a failure occur midair. (Still seems like it should be a solvable problem, but...)

It sounds like we would need an aerial tram in order to provide a viable passenger experience. But, it also sounds like aerial trams would be too slow and too infrequent to provide a viable service.

So. This idea is probably DOA.
I'm sure you could come up with some system to have all cars come to a stop, but now you're looking at developing a niche, one off system when you could also just not and put the parking somewhere else and save loads of money.

In the event someone does invent such a system, maybe it would be practical. But until then, yeah probably not.
 
How sufficient would it be to just have the cable car move slowly enough while in the station, so that passengers with luggage have enough time to get on and off?
 

Back
Top