Tobin Bridge Relocation/Replacement

[Vagabond]

That's probably one of my favorite bonkers crayon drawings ever... like, who cares that Sullivan Square Redevelopment or the Everett Lower Broadway District dreams exist! Screw 'Em!

I had the same thought - then fell in love with the idea of trashing route 1 through chelsea and charlestown...

 

[kingofsheeba]

Should we move this to Transit/Infrastructure?

 

[Equilibria]

Should we move this to Transit/Infrastructure?

It's being discussed there already in General Infrastructure, but this feels like enough of a visioning exercise (even as a real study) that it belongs here. It's not at all imminent.

I guess it's up to @BeeLine and @vanshnookenraggen whether to move this thread and merge in the posts on the General Infrastructure thread...

 

[TomOfBoston]

Why not relocate the port facilities upriver so that a high bridge is not needed!

 

[Stlin]

Why not relocate the port facilities upriver so that a high bridge is not needed!

Now that's a god mode pitch. But in all seriousness, how badly would we snarl traffic if we went with a modern moveable bridge?

 

[Charlie_mta]

I would shift the Tobin Bridge to the west on the Chelsea side. Here's a map of my idea. The red is the elevated bridge and expressway, and the green is cut-and-cover tunnel. Yellow are the portals. The pink road and ramps on the left side of the map is a new approach road connecting to Beacham St and 2nd St. The bridge over the Mystic River would be double deck, but change to standard side-by-side expressway at the north end of the bridge above Island End River,

 

[Teban54]

Question: Realistically speaking, what's the likelihood of the replacement being a tunnel?

 

[393b40]

Question: Realistically speaking, what's the likelihood of the replacement being a tunnel?

0.0%

Also this thread is pure wish casting . There's not going to be highway rerouting or LRV. The only feasible line is basically eminent domain the properties on the western side of the bridge to build the replacement then tear the old one down.

 

[vanshnookenraggen]

Yeah, it's getting foamy in here.

 

[Equilibria]

Question: Realistically speaking, what's the likelihood of the replacement being a tunnel?

75-100%, assuming (a) there is ever a replacement and (b) development of the Mystic waterfront doesn't eliminate the need to keep the industrial waterway clear.

What is the chance of any replacement of the Tobin occurring before at least 2040? 0%.

 

[ritchiew]

Where could one find the actual RFP? MassDOT said they would release one this week, and it should give a lot more parameters for what they're looking for.

 

[Highwayguy]

Question: Realistically speaking, what's the likelihood of the replacement being a tunnel?

0.0%
Also this thread is pure wish casting . There's not going to be highway rerouting or LRV.

Given the difficulty of finding a parallel alignment for a new bridge without eminent domain-ing 5 blocks of Downtown Chelsea, I think there is at least a 15% chance that a tunnel emerges as the preferred alternative; unlikely but not outlandish. No way that the existing structure isn't retained during the construction of Tobin 2.0.

Also per current DOT policy, the new structure would have to have bus lanes. So it is possible (if unlikely) that they are future proofed like the Champlain bridge in MTL to accommodate light rail.

 

[JeffDowntown]

Given the difficulty of finding a parallel alignment for a new bridge without eminent domain-ing 5 blocks of Downtown Chelsea, I think there is at least a 15% chance that a tunnel emerges as the preferred alternative; unlikely but not outlandish. No way that the existing structure isn't retained during the construction of Tobin 2.0.

Also per current DOT policy, the new structure would have to have bus lanes. So it is possible (if unlikely) that they are future proofed like the Champlain bridge in MTL to accommodate light rail.

The downtown Chelsea issue has always been my reasoning about why a tunnel might be considered.

 

[RandomWalk]

The issue with a tunnel is that it will inevitably become a Big Dig 2.0, which will make it a political non-starter.

The potential to transform Chelsea is like catnip for all the urban design ideas that haven’t gotten traction. Once they get included, the scope and budget will grow to a level that will not get funding unless Tip O’Neill rises from the dead to reclaim his gavel.

 

[stefal]

The 2-year community input period will result in a half-tunnel, half-bridge structure with the portal in the middle of the Mystic.

 

[stick n move]

The 2-year community input period will result in a half-tunnel, half-bridge structure with the portal in the middle of the Mystic.

Haha. Dont forget that theyre also gonna need to knock a few floors off the top of that bridge proposal too to appease the neighbors for… reasons.

 

[bigpicture7]

Haha. Dont forget that theyre also gonna need to knock a few floors off the top of that bridge proposal too to appease the neighbors for… reasons.

And with 7 units of affordable housing squeezed into the foundations of one pier, and 700 parking spaces in the other.

 

[Teban54]

Amid all the talks of how to put a transit service (whether BRT, LRT or HRT) on Tobin's replacement and where it should be, I think there's a related question: Which transit route should be there?

Obviously, the most realistic near-term answer is the (T)111. But what if we actually manage to put in tracks?

Looking at the recent discussions, an Orange Line branch seems like the most popular choice. But I don't think that's the right one: doing so halves (maximum) capacity on the main OL route north of Community College, including Sullivan, Assembly, Wellington and Malden Center, each one of which can't afford to lose service. It's even worse than the more common proposal of branching OL at Sullivan via the Eastern Route, which at least maintains full service to Sullivan.

In the medium term, there's another option: What if we make it a branch of the Green Line from North Station?

The tunnel that leads to Tobin Bridge is already very close to North Station. Build a tunnel that takes a turn and go under the Charles, build a flying junction at GL North Station (which will hopefully be easier than otherwise would, given that the two GL tracks are on different levels there), and you're there. Northside Green Line has much more spare capacity than southside today (and remains so under most GL Reconfiguration proposals), so you can easily extend, say, the C trains to take on this branch to Chelsea.

If the GL flyover at North Station is infeasible, another potential idea is to use the old center tracks at Haymarket (with a crossover north of the present-day station to get to the center tracks), though I'm not sure how much of those structures remain intact today. For a cheap build, you can either use the portal to get to street level, and follow the route of the 111 bus today. For a more expensive build, use the center tracks to separate from the main GL tracks, but stay underground with separate North Station platforms somewhere.

(@vanshnookenraggen , you need to update your track map to make the C terminate at Government Center.)

In the long/fantasy term, I think the route that makes the most sense is what I called the "5th trunk in downtown Boston": A route from North Station that follows Congress St, through State (BL/OL), the heart Financial District (Post Office Square), and South Station (RL). This route can be either LRT or HRT, and both have merits:

• LRT allows the route to absorb other streetcar/bus routes immediately to the north and south of downtown, in addition to the Chelsea branch via Tobin. Examples include the 93/T7 route through Charlestown, Everett (Broadway), the (T)7 route through Summer St to South Boston, etc. This can be an LRT version of the downtown transit corridor that's planned in the Bus Network Redesign, and the second LRT trunk similar to what the Green Line does today.
• HRT allows a longer radial route that can possibly extend beyond Chelsea, such as to Everett and Revere, both of which need better, faster transit options. On the southern end, options beyond South Station also exist, such as F-Line's "Red X" proposal that absorbs one of the Red Line branches, or - likely in a fantasy world - proper rapid transit conversion of the Fairmount Line.

I made this God-mode proposal a while back with more explanations there, and a sketch of the downtown route is shown below. If we can get HRT on the Tobin ROW (which is ambitious, I know), it may bring the proposal one step closer from fantasy range.

 

[tysmith95]

The issue with a tunnel is that it will inevitably become a Big Dig 2.0, which will make it a political non-starter.

The potential to transform Chelsea is like catnip for all the urban design ideas that haven’t gotten traction. Once they get included, the scope and budget will grow to a level that will not get funding unless Tip O’Neill rises from the dead to reclaim his gavel.

Modern tunnel boaring machines would make this less disruptive and expensive compared to the cut and cover big dig.

It would be a similar project to the Alaska Viaduct project in Seattle. That cost around 3 billion.

Monetizing real estate gained would help defer some of the cost.

Anyhow, I think downgrading the Tobin to a boulevard and adding some light rail to the project would be a better use of funds.

 

[JeffDowntown]

Amid all the talks of how to put a transit service (whether BRT, LRT or HRT) on Tobin's replacement and where it should be, I think there's a related question: Which transit route should be there?

Obviously, the most realistic near-term answer is the (T)111. But what if we actually manage to put in tracks?

Looking at the recent discussions, an Orange Line branch seems like the most popular choice. But I don't think that's the right one: doing so halves (maximum) capacity on the main OL route north of Community College, including Sullivan, Assembly, Wellington and Malden Center, each one of which can't afford to lose service. It's even worse than the more common proposal of branching OL at Sullivan via the Eastern Route, which at least maintains full service to Sullivan.

In the medium term, there's another option: What if we make it a branch of the Green Line from North Station?
View attachment 43002
The tunnel that leads to Tobin Bridge is already very close to North Station. Build a tunnel that takes a turn and go under the Charles, build a flying junction at GL North Station (which will hopefully be easier than otherwise would, given that the two GL tracks are on different levels there), and you're there. Northside Green Line has much more spare capacity than southside today (and remains so under most GL Reconfiguration proposals), so you can easily extend, say, the C trains to take on this branch to Chelsea.

If the GL flyover at North Station is infeasible, another potential idea is to use the old center tracks at Haymarket (with a crossover north of the present-day station to get to the center tracks), though I'm not sure how much of those structures remain intact today. For a cheap build, you can either use the portal to get to street level, and follow the route of the 111 bus today. For a more expensive build, use the center tracks to separate from the main GL tracks, but stay underground with separate North Station platforms somewhere.
View attachment 43003
(@vanshnookenraggen , you need to update your track map to make the C terminate at Government Center.)

In the long/fantasy term, I think the route that makes the most sense is what I called the "5th trunk in downtown Boston": A route from North Station that follows Congress St, through State (BL/OL), the heart Financial District (Post Office Square), and South Station (RL). This route can be either LRT or HRT, and both have merits:

• LRT allows the route to absorb other streetcar/bus routes immediately to the north and south of downtown, in addition to the Chelsea branch via Tobin. Examples include the 93/T7 route through Charlestown, Everett (Broadway), the (T)7 route through Summer St to South Boston, etc. This can be an LRT version of the downtown transit corridor that's planned in the Bus Network Redesign, and the second LRT trunk similar to what the Green Line does today.
• HRT allows a longer radial route that can possibly extend beyond Chelsea, such as to Everett and Revere, both of which need better, faster transit options. On the southern end, options beyond South Station also exist, such as F-Line's "Red X" proposal that absorbs one of the Red Line branches, or - likely in a fantasy world - proper rapid transit conversion of the Fairmount Line.

I made this God-mode proposal a while back with more explanations there, and a sketch of the downtown route is shown below. If we can get HRT on the Tobin ROW (which is ambitious, I know), it may bring the proposal one step closer from fantasy range.

Quick comment on the Orange Line split "halving capacity". Nothing I have ever seen in proposed train headways for the current Orange Line ever comes close to using the new capacity of the downtown Main Line tunnel once signal modernization is completed. So what you really need to keep both branches at reasonable service levels is more cars (and operators).