Crazy Transit Pitches

[Teban54]

Some super-quick math (~250 feet tall, ~3500 feet of travel from first channel to underground segment of the roadway) shows a grade steeper than any on the MBTA system: 7% versus about 6.5% on the Causeway Street Tunnel up to the Lechmere viaduct. That doesn't bode well for anything other than BRT.

IIRC, I think one of the documents that @Riverside found showed that 7% grade is almost exactly the maximum grade that LRT can run on. So there might still be hope, I guess...?

But for HRT, yes it will probably have to be underground if it happens. The problem then becomes that it will have to be a standalone project, instead of being tied to the bridge replacement, which means very little chance of materializing.

 

[vanshnookenraggen]

Go under not over the channel.

Then it wouldn't be a bridge. And if it's not a bridge, it's not getting built.

 

[ulrichomega]

Ah, I think I was misinterpreting numbers. The clearance height is only about 135 feet, giving a much more reasonable grade of under 4% for the point I selected. The overall height is the number I was quoting before, which makes more sense. Those grades do seem to give some wiggle room for where a portal could be located, though I'm still not sure what we'd be talking about for HRT grade limitations.

 

[ritchiew]

Some super-quick math (~250 feet tall, ~3500 feet of travel from first channel to underground segment of the roadway) shows a grade steeper than any on the MBTA system: 7% versus about 6.5% on the Causeway Street Tunnel up to the Lechmere viaduct. That doesn't bode well for anything other than BRT.

Ah, I think I was misinterpreting numbers. The clearance height is only about 135 feet, giving a much more reasonable grade of under 4% for the point I selected. The overall height is the number I was quoting before, which makes more sense. Those grades do seem to give some wiggle room for where a portal could be located, though I'm still not sure what we'd be talking about for HRT grade limitations.

Good catch. Also, I think that ~3500ft is an underestimate. The bridge climbs consistently until basically the very center, which is >5000ft from the Charlestown portal. (The bridge isn't at full height at the channel I think you were measuring to.) Even if you just measure to the bank of the Mystic, that's only a ~3% grade, which works for any rapid transit.

 

[HenryAlan]

Ignoring the fact that the design process has already started and any major additions to the design requirements are unlikely to be added: What kind of transit could we even expect to add to such a new structure? Bus lanes for a Silver Line/BRT addition are obvious, but do the grades of the structure even vaguely support any sort of rail transit? I've often toyed with the idea of an Orange Line branch over a NuTobin ala the Ben Franklin Bridge, but that thing is so high I don't know that you can do much with it.

We can probably expect bus lanes, and some sort of path for bikes and pedestrians. The article states that these are mandated by current MassDOT guidelines:

MassDOT's updated design standards would require adequate facilities for bike and pedestrian traffic, as well as accommodation for bus traffic, on any new replacement bridge.

Although it sounds like it theoretically could include rail, that's not mandated, and therefore very unlikely to be funded.

 

[JeffDowntown]

Then it wouldn't be a bridge. And if it's not a bridge, it's not getting built.

We'll that's a defeatist attitude.

Of course if you only envision a bridge that is certainly all that will ever be build.

 

[king_vibe]

Boston Planning & Development Agency planners, as seems to be their wont (sorry, folks - if the shoe fits...) threw a bunch of wild-eyed, long-term transit visioning into the latest East Boston rezoning study, including this crayon of alternatives for extending the Blue Line:

View attachment 42553

FYI: If you see the map in context (page 87 of the PDF, 169-170 of the printed doc: https://www.bostonplans.org/getattachment/64e6e176-1936-46e7-abb2-bf131fdca6fe), it's clear that crayon is options, not a vision for an octopus-like line.

Other notable ideas and/or intent expressed about use of streets in the area:

• advocating for using the 1A corridor as some kind of additional bus highway and adding Revere<>Eastie<>Chelsea bus service (PDF pages 80-83)
• Redrawing Day Square to put the SL3 and T104 on dedicated surface lanes (PDF pages 51-53)**
• Fairly lengthy bus lanes up Meridian (PDF pages 45-50)
• A whole mess of cycling improvements (scattered throughout, PDF page 34 and onwards)

**Wouldn't that run afoul of the vehicular access detailed in the 355 Bennington St. project presentations from last year? https://www.bostonplans.org/projects/development-projects/355-bennington-street

A Blue Line extension through Kenmore, Fenway, and LMA via Brookline Ave would be an lifesaver for those areas and would provide critical redundancy for the creaky Green Line. It makes too much sense to ever do it.

 

[Charlie_mta]

https://mass.streetsblog.org/2023/09/20/massdot-starts-planning-for-tobin-bridge-replacement

Looks like it's time to revive our earlier discussion of just what you could do with a project like this...

The new bridge absolutely needs to have a separate ped/bike path, a wide one. Also I'm thinking an exclusive busway, strong enough to convert to light rail in the future, for an LRV to Chelsea.

 

[Riverside]

Dipping in for a briefer-than-usual-for-me comment: yes, IIRC the max grade for LRT is 7%, although I believe that comes with the caveat that the incline not be longer than 500 feet. That being said, a very quick Google suggests that highway grade requirements are similar, so in theory if cars can get from the CAT up to the top of the Tobin, then the Green Line should too.

But yeah, my vote would be for a dedicated busway that can be converted to mixed LRT/BRT. Even just a dedicated busway would be transformative.

 

[Delvin4519]

Dipping in for a briefer-than-usual-for-me comment: yes, IIRC the max grade for LRT is 7%, although I believe that comes with the caveat that the incline not be longer than 500 feet. That being said, a very quick Google suggests that highway grade requirements are similar, so in theory if cars can get from the CAT up to the top of the Tobin, then the Green Line should too.

But yeah, my vote would be for a dedicated busway that can be converted to mixed LRT/BRT. Even just a dedicated busway would be transformative.

Would this mean the 111 will finally make stops at the Spaulding Hospital, or the Navy Yard @ Chelsea St., 40 - 50 years from now? This would increase transit service in a transit desert southwest of Chelsea by like 600%.

One of the routes that I crayoned out with no transit route today is Chelsea -> Kendall -> Central, via Navy Yard & Austin St, highlighted in Pink. I suppose a majority of the service would still go to Haymarket, but perhaps some should divert to Main & Austin St. and run towards Lechmere and Kendall to reach Central Sq.

 

[Teban54]

Would this mean the 111 will finally make stops at the Spaulding Hospital, or the Navy Yard @ Chelsea St., 40 - 50 years from now? This would increase transit service in a transit desert southwest of Chelsea by like 600%.

One of the routes that I crayoned out with no transit route today is Chelsea -> Kendall -> Central, via Navy Yard & Austin St, highlighted in Pink. I suppose a majority of the service would still go to Haymarket, but perhaps some should divert to Main & Austin St. and run towards Lechmere and Kendall to reach Central Sq.

View attachment 42871View attachment 42872

FWIW, Chelsea-Kendall will likely be served by one of the several SL3/6 proposals that are in planning. Alt 7 calls for a Chelsea-Kendall OSR, while all other alternatives allow Chelsea riders to transfer between an extended SL3 and the new SL6 at Everett. On the other hand, Charlestown-Kendall will get its own OSR via the T101 in the redesign.

While a route like what you suggested would be nice, I have doubts on it materializing, especially given that it doesn't serve the major transfer hub Sullivan. I can totally see Tobin continuing to be used exclusively for the T111.

 

[Delvin4519]

FWIW, Chelsea-Kendall will likely be served by one of the several SL3/6 proposals that are in planning. Alt 7 calls for a Chelsea-Kendall OSR, while all other alternatives allow Chelsea riders to transfer between an extended SL3 and the new SL6 at Everett. On the other hand, Charlestown-Kendall will get its own OSR via the T101 in the redesign.

While a route like what you suggested would be nice, I have doubts on it materializing, especially given that it doesn't serve the major transfer hub Sullivan. I can totally see Tobin continuing to be used exclusively for the T111.

Yea. The T101 and the SL3/SL6 routing is kind of very indirect, going out of their way and then doube backing to serve Community College making twisty turns and an indirect route, which kind of leaves no direct connection from the Spaulding Hospital to the Community College station. These two are in the same neighborhood but are about 32 minutes apart by walking, since the current 92/93 buses barely even run hourly with no Sunday service.

Past Community College, to get to Spaulding Hospital from Lechmere is 40 minutes, and Kendall MIT station is 1 hour, due to lack of bike lanes on the straight line direct connection to Cambridge via Gilmore Birdge as well as the overwhelming amount of cars and their speed in Charlestown. Existing transit options are much longer, meaning car-free or transit-dependent people are effectively stuck at no more than walking speed in the insular hilly neighborhood, which is woefully inadequate in a a sprawing car-centric city. The proposed T101's routing in Charlestown is very poor in that way, effectively duplicating the Orange Line.

From Everett and Winter Hill/Assembly. Something like merging with the CT2 from Sullivan to get to Kendall would've made more sense, while Chelsea/Revere should've use the Charlestown routing. That plus the 92/93/OL/GL would form a gridded service, vs. the hub and spoke model at Sullivan Sq. 109/CT2 would run NE/SW, and 111/Kendall would also run NE/SW. Then the 92/93/OL/GL running NW/SE.

These are the most direct routes to serve Kendall Sq., much more direct than the SL3/SL6, or the T101. It would connect Union Sq., directly with Assembly Row, and shorten travel times to Winter Hill and Medford Sq., from Kendall, instead of diverting to the Chelsea routing. I suppose Everett could divert to Community College, but that would make serving Sullivan Sq. station a lengthy detour from the route. I wanted to preserve some of the proposed T109 by running to Union Sq. before diverting to Kendall. There's also the GLX, but the Medford routing diverts after Magoun Sq. to serve Main St, so there's only overlap from East Somerville, to barely Magoun Sq., with the GLX.

While the T111 would likely continue serving Haymarket, it is kind of a missed opportunity to straighten as many bus lines as possible. Two branches from Chelsea to split into Haymarket or Kendall bound service would provide a lot more one seat rides in Chelsea and Revere, potentially allowing through running from Revere Center, down Broadway to Kendall, to complement the T111 from Woodlawn to Haymarket. This would allow two routes to use the Tobin routing through Charlestown. It would also turn 3 seat rides in Revere and Chelsea into one seat rides, massively cutting down travel time.

 

[Aprehensive_Words]

Most Chelsea residents don't work in Kendall, though. They work blue- and pink-collar jobs downtown, in hospitals and industrial areas, and at the airport.

It doesn't do them much good to make their commutes longer when, to @Teban54's point, they'll get Kendall connectivity through the SL3 extension and new SL6/7. Given how heavily the route is used, it seems pretty obvious to me, at least, that it ought not be tinkered with, save maybe adding a couple stops to things already on the way (e.g. Navy Yard and the Bunker Hill housing redevelopment) if infrastructure permits.

Here's the Census On the Map view of the top 25 employment destinations for the census tracts that most closely follow the 111's route:

Because this isn't a great graphic, here's what those tracts/worker numbers correspond to:

1. Chelsea industrial area west of Route 1: 1,017 workers
2. Financial District/Leather District/South Station: 645
3. Everett industrial areas south of Revere Beach Parkway and between the Malden River and the Northern Strand bike path (includes the casino): 631
4. Logan: 493
5. Haymarket/Gov't. Center/State Street: 489
6. MGH+Charles River Plaza (Whole Foods): 426
7. Southern half of Longwood Medical Center: 270
8. Prudential Center+Hancock+Old Hancock: 242
9. Woburn industrial area @95/93: 241
10. Core Harvard University+Spaulding Cambridge: 211
11. Malden industrial area along Commercial Street and the Northern Strand: 196
12. Brickbottom/Inner Belt/Union Square industrial east of Webster Ave.: 184*
13. Newton Wellesley Hospital/Lasell University/Wellesley Lower Falls: 182
14. Park Plaza Hotel/Four Seasons/etc. immediately around the Columbus-Arlington-Stuart intersection: 180
15. Seaport District+Fort Point: 175
16. Northern half of Longwood: 160
17. Chelsea industrial area north of the SL3 and south of Crescent Ave.: 159
18. Eastie industrial area along 1A: 142
19. MIT+Kendall south of Broadway: 141
20. Assembly: 138
21. Kendall north of Broadway: 138
22. Southie industrial area around the Reserved Channel+Flynn Marine Park: 133
23. Boston Landing+Brighton north of the Pike: 127
24. Chelsea south of Beacham+Marginal Street: 111
25. North Station/Suffolk County Jail/West End west of Causeway and Staniford: 110

*The Census data is from 2020, so before the commercial laundry, etc. in this bit of Union Square were torn down in favor of lab space.

TLDR:
279 people need to get to Kendall; 2,559 people need to get out of Chelsea to places that are at most a 2-seat ride away from home based on the current 111 alignment. If you still want to connect the 111 to Kendall, do it via Causeway, Staniford, Cambridge Street and the Longfellow Bridge.

 

[Teban54]

Most Chelsea residents don't work in Kendall, though. They work blue- and pink-collar jobs downtown, in hospitals and industrial areas, and at the airport.

It doesn't do them much good to make their commutes longer when, to @Teban54's point, they'll get Kendall connectivity through the SL3 extension and new SL6/7. Given how heavily the route is used, it seems pretty obvious to me, at least, that it ought not be tinkered with, save maybe adding a couple stops to things already on the way (e.g. Navy Yard and the Bunker Hill housing redevelopment) if infrastructure permits.

Here's the Census On the Map view of the top 25 employment destinations for the census tracts that most closely follow the 111's route:
View attachment 42879

Because this isn't a great graphic, here's what those tracts/worker numbers correspond to:

1. Chelsea industrial area west of Route 1: 1,017 workers
2. Financial District/Leather District/South Station: 645
3. Everett industrial areas south of Revere Beach Parkway and between the Malden River and the Northern Strand bike path (includes the casino): 631
4. Logan: 493
5. Haymarket/Gov't. Center/State Street: 489
6. MGH+Charles River Plaza (Whole Foods): 426
7. Southern half of Longwood Medical Center: 270
8. Prudential Center+Hancock+Old Hancock: 242
9. Woburn industrial area @95/93: 241
10. Core Harvard University+Spaulding Cambridge: 211
11. Malden industrial area along Commercial Street and the Northern Strand: 196
12. Brickbottom/Inner Belt/Union Square industrial east of Webster Ave.: 184*
13. Newton Wellesley Hospital/Lasell University/Wellesley Lower Falls: 182
14. Park Plaza Hotel/Four Seasons/etc. immediately around the Columbus-Arlington-Stuart intersection: 180
15. Seaport District+Fort Point: 175
16. Northern half of Longwood: 160
17. Chelsea industrial area north of the SL3 and south of Crescent Ave.: 159
18. Eastie industrial area along 1A: 142
19. MIT+Kendall south of Broadway: 141
20. Assembly: 138
21. Kendall north of Broadway: 138
22. Southie industrial area around the Reserved Channel+Flynn Marine Park: 133
23. Boston Landing+Brighton north of the Pike: 127
24. Chelsea south of Beacham+Marginal Street: 111
25. North Station/Suffolk County Jail/West End west of Causeway and Staniford: 110

*The Census data is from 2020, so before the commercial laundry, etc. in this bit of Union Square were torn down in favor of lab space.

TLDR:
279 people need to get to Kendall; 2,559 people need to get out of Chelsea to places that are at most a 2-seat ride away from home based on the current 111 alignment. If you still want to connect the 111 to Kendall, do it via Causeway, Staniford, Cambridge Street and the Longfellow Bridge.

I think there's a balance between "taking people where they already work at" and "enabling new connections to major and growing job destinations, so that Chelsea residents are better equipped for Kendall jobs, and/or people getting a job in Kendall see Chelsea as a viable option". In other words, it's not clear if employment at Kendall is suppressed for Chelsea residents because of how difficult it is to get there.

But I agree with your overall point: given that SL3/6 already improves Chelsea-Kendall connectivity significantly, it's probably better in the short term to focus on existing destinations. In the long term, they'll probably have an Urban Ring connection to Kendall anyway.

 

[ulrichomega]

Dipping in for a briefer-than-usual-for-me comment: yes, IIRC the max grade for LRT is 7%, although I believe that comes with the caveat that the incline not be longer than 500 feet. That being said, a very quick Google suggests that highway grade requirements are similar, so in theory if cars can get from the CAT up to the top of the Tobin, then the Green Line should too.

But yeah, my vote would be for a dedicated busway that can be converted to mixed LRT/BRT. Even just a dedicated busway would be transformative.

I'm seeing 4% on level terrain, with a 1% increase allowed in urban areas. Let's call it 4% for now because I'm not sure if "parking lot next to river" counts as urban, and I'm not sure what sustained LRT grades are allowed to be for lengths this long.

From the point where the Tobin goes over the Mystic to the eastern corner of Barry Field is 1630 ft. That allows for a 65ft drop in height down from 135 feet, giving a platform height of 70ft, one of the tallest in the world (though not the tallest by any stretch). This is comparable to Smith-9th on the F/G lines in NYC. but far less than Hualongqiao station in Chongqing. The current road surface seems to try and stay very level between these two points, though I'd presume that's because the toll booth used to be located there, and so in the name of conserving height the new design could dip down there. Obviously a station right on the water there isn't the best location for service, but it would allow for a reasonably spaced station in City Square (the actual siting and building of a station there are an entirely different story, however). After a Little Mystic Channel station, presumably you could zoom the bridge down to standard road clearance levels pretty fast, somewhere around Vine St, removing more of the existing viaduct and prepping for your City Square Station, wherever that ends up.

I'm now more supportive of a rail design, though I still question the connections made on either end. A BRT reservation with provisions for LRT conversion seems like the best way forward.

 

[Riverside]

I'm looking more carefully at a "Bury the B" Comm Ave subway, which has often been tossed around here on aB but I can't figure much detail on. One thing I'm doing is comparing a Comm Ave radial tunnel to a Mass Pike circumferential tunnel. The possibility of a Comm Ave subway has often been tossed around relatively casually, but it seems to me that conditions probably are similar under the Mass Pike? (Which has been railroad tracks or highway since forever.)

(Specifically I am looking at a Mass Pike subway that runs between Comm Ave and Beacon St [the C/D Beacon Junction].)

So, two questions:

1) In general are there any formalized details on a "Bury the B" Comm Ave subway?

2) What would difference in engineering complexity be between a Comm Ave subway and a Mass Pike subway?

 

[JeffDowntown]

I'm looking more carefully at a "Bury the B" Comm Ave subway, which has often been tossed around here on aB but I can't figure much detail on. One thing I'm doing is comparing a Comm Ave radial tunnel to a Mass Pike circumferential tunnel. The possibility of a Comm Ave subway has often been tossed around relatively casually, but it seems to me that conditions probably are similar under the Mass Pike? (Which has been railroad tracks or highway since forever.)

(Specifically I am looking at a Mass Pike subway that runs between Comm Ave and Beacon St [the C/D Beacon Junction].)

So, two questions:

1) In general are there any formalized details on a "Bury the B" Comm Ave subway?

2) What would difference in engineering complexity be between a Comm Ave subway and a Mass Pike subway?

Comm. Ave. has a much higher ridership in walking distance score. Under the Pike has all the bad characteristics of center median transit outside the urban core.

 

[Riverside]

Comm. Ave. has a much higher ridership in walking distance score. Under the Pike has all the bad characteristics of center median transit outside the urban core.

For more detail, I'm not necessarily suggesting a Mass Pike subway instead of a Comm Ave subway -- really I'm just using the Comm Ave subway as a point of comparison to evaluate a Mass Pike subway.

This is what I've been thinking about:

• Gold: Kendall <> West Station
• Gold: Kendall <> Brookline Village
• Crimson: Harvard <> Allston <> West Station <> Longwood
• Blue: Kenmore <> West Station

I think all of that would be too much to try to funnel underneath Comm Ave, plus Comm Ave still doesn't actually get you over to Longwood. The Mass Pike provides a ROW connecting BU Bridge with Beacon Junction, and does so directly and on land that -- as far as I know -- has been railroads/highways since it was filled in, and so shouldn't have any surprise utilities etc etc.

Anyway, I'm saying that we've often talked about "Bury the B" as if it were relatively simple, and I'm saying -- other than needing to shut down part of the Pike during construction -- that it looks like, on spec, it should be equally easy/difficult to dig under the Pike.

Also, though:

Comm. Ave. has a much higher ridership in walking distance score. Under the Pike has all the bad characteristics of center median transit outside the urban core.

What ultimately matters here is the location of the stations, not the paths. With rapid transit stop spacing, there would only be one BU station, probably somewhere near St Mary's St; to me, I don't see a huge difference in walkshed between Comm Ave @ St. Mary's and Mass Pike @ St Mary's, and indeed depending on headhouse locations they could easily be near-identical. (Plus, a Mass Pike station could have a second headhouse to the south of the Pike, improving access from there as well.)

 

[ritchiew]

2) What would difference in engineering complexity be between a Comm Ave subway and a Mass Pike subway?

Sorry if I'm missing what you're getting at here, but these seem really different. Going under the Pike, I assume you'd be tunneling. But you could maybe, plausibly cut and cover a Comm Ave subway.
Right out of the Blandford Portal, you could divert the B line onto temporary tracks on Comm Ave Westbound, and move all car traffic into the current eastbound lanes. Cut and cover the median, and the only bit of tunneling would be under the highway. Setting up temporary tracks and cutting car lanes like that is roughly what they did for the Longfellow rehabilitation, isn't it? Anyways, if there is space for that, it ought to be way cheaper and faster than tunneling the whole length.

 

[Koopzilla24]

What ultimately matters here is the location of the stations, not the paths. With rapid transit stop spacing, there would only be one BU station, probably somewhere near St Mary's St; to me, I don't see a huge difference in walkshed between Comm Ave @ St. Mary's and Mass Pike @ St Mary's, and indeed depending on headhouse locations they could easily be near-identical. (Plus, a Mass Pike station could have a second headhouse to the south of the Pike, improving access from there as well.)

People are very fickle and the path matters a lot more than numbers on paper would suggest. Not having to cross over a very unpleasant highway is make or break for many. Placing it in a highway median-like location also restricts the useful catchment on both sides of the station instead of just one as it would be adding an additional 100ft of walking from each head house to cross the lanes. More people on the St Mary’s side would likely go to Park Dr, and for that reason I’d suggest if it is going to cross under the Pike anyway I’d put the station under St Mary’s @ Mountfort. That would put it closer to the residents of Fenway-Kenmore/Brookline extending its catchment there, and have the BU catchment that’s limited by the Charles and Storrow anyway have to cross the Pike. Either way someone’s crossing the highway and I’d make the demographically slightly more youthful one be the only one to do so.