Crazy Transit Pitches

[BeyondRevenue]

Throwing this over the transom and running...

 

[Teban54]

I will say, from reading your post I still get the idea that you're at least partially in the mindset of a heavy rail line, with large, complex stations. This would not be that. This would be an at-grade tram route, like the rest of the C Branch already is. A new station at Landsdowne would not be a complex structure, just a basic median street stop, same at Science Park.

I admit that I was indeed in the mindset of a "heavy metro" line, or thinking that your proposal was replacing a BLX via Storrow. But that's primarily because I think Blue Line deserves to be extended beyond Charles/MGH, or at least there should be another heavy metro line to the west.

"Heavy metro" here refers to @Riverside 's terminology in this post: either HRT, high-capacity light rail with largely grade-separated ROW and longer stop spacing (GLX and the D branch may count), or regional rail with rapid transit frequencies.

• In that same post, @Riverside explained the need for a heavy metro line to the west better than I could: There's a dearth of heavy metro service there between the Red and Orange lines, which include places like Kenmore, BU, Longwood, Allston, Brighton, Newton Corner, Watertown and maybe even Waltham, all with good density and high demands. It just happens that whatever routing you take, BLX is the best way to address them in the long term, as opposed to creating a new line.

What you proposed is a textbook example of a "light metro" line, or basically a streetcar route. This brings a few subtle distinctions, regardless of whether it's connected to the C branch:

• For one, its purpose is very different from a BLX. The latter brings passengers through Storrow, for a rapid ride to Kenmore (and possibly points further west). The former seems to aim more at bringing passengers to Storrow or the revamped Charles River esplanade.
• For another, catchment along the route suddenly becomes super important in assessing its effectiveness - and this is where I think this corridor doesn't quite make the cut. Storrow doesn't have great density nearby, and is too far from the commercial districts around Copley. Realistically, its demand will primarily rely on park-goers to the Charles River esplanade. And while that's not a bad idea in itself, I'm not sure if it's sufficient to support a light rail line (especially when there are many other established bus routes that make a stronger case for light rail conversion).

While a light metro Storrow streetcar shouldn't replace a heavy metro BLX, I think having both co-exist isn't out of the question. Put BLX in a shallow cut (like F-Line suggested), cover it up, and put the streetcar on top with pedestrian crossings. The question is whether the need is there to justify both.

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Forcing the C branch to feed into the Storrow streetcar can indeed be a way to improve the latter's patronage (and is certainly better than cutting the C back to Kenmore), but you run into political issues such as...

quite simply good luck telling all those rich Brooklineites that no, if you want to get to Malden now you've got to change trains twice. Not happening.

I would imagine those "rich Brooklineites" would be more concerned with losing their OSRs to the Central Subway - as well as a longer, slower ride to GC - than having to transfer twice to Malden instead of once.

----------------------------------

If you do want to put light metro on Storrow though, here's an alternative idea.

@Riverside once proposed a "Rose Line" that explicitly serves as a tourist trolley, through the Greenway and North End:

A route like this serves basically the same purpose as the Kenmore-Storrow-North Station streetcar line: Primarily tourist and recreational destinations (which the Charles River esplanade is one), and secondarily filling gaps in transit coverage that don't deserve a full subway line (North End, West End and northern Back Bay). It also allows you to care much less about speed and efficiency.

So I think through-running the Storrow streetcar line with this Rose Line is probably the best choice. Whether you want to also through-run this with the C branch is another question, but the route will likely be too long.

 

[Riverside]

The reason I think option C is what should be done is not necessarily because it's the best, a terminus at Charles/MGH would likely make more sense in that regard and neatly cap the service, but because quite simply good luck telling all those rich Brooklineites that no, if you want to get to Malden now you've got to change trains twice. Not happening.

While I agree with @Teban54 that the bigger concern probably is the loss of the OSR to Back Bay, I take your point.

That being said, I think the bigger point here is that the only way C-to-Esplanade happens (in my opinion) is if the C gets kicked out of the Boylston Street Subway — ie in that scenario, Brookline would likely be choosing between

A) Forced transfer at Kenmore
or
B) Transfer at Kenmore, or transfer at Charles/MGH

In which case option B would probably seem preferable. But as long as the option exists to send C through the Boylston St Subway, then a reroute on Storrow seems less likely.

@Teban54 love the shoutout on the Rose Line, thank you thank you. Yeah, I think South Station <> North Station <> Cleveland Circle would indeed be too long, but you could layer staggered services on top of each other to make a continuous corridor.

 

[thepixelnation]

The reason I think option C is what should be done is not necessarily because it's the best, a terminus at Charles/MGH would likely make more sense in that regard and neatly cap the service, but because quite simply good luck telling all those rich Brooklineites that no, if you want to get to Malden now you've got to change trains twice. Not happening.

But you're right that it's not a "load-bearing" service. It's not designed to be, just like the current C branch isn't. It's more of a hybrid between a local bus service and a cross-city rapid transit line. I'm also less concerned about the isolation problem seeing as the route would not use the central subway, which is by far where the worst delays occur and where contagion is incredibly bad. The line also still functions well without the turn into downtown should it suddenly become necessary because of service interruptions, but this should obviously be avoided whenever possible to minimize crowding at Charles/MGH and State/DTX.

I don't think there are a bunch of rich Brooklineites who are really taking the T to Malden, or even considering the thought.

 

[Riverside]

Throwing this over the transom and running...

View attachment 43871

I like how it looks, looks cool!

 

[Teban54]

Coming back to this silliness, and partially inspired by an alternative @Teban54 put forward here, I've been noodling around with using a short tunnel under Fitchburg St to connect the Grand Junction line with the Medford Branch's yard leads, from which a flying junction could then grab the New Washington St alignment described above.

View attachment 43523
[...]

The two things that terrify me about this version of the silly idea:

1. The silliness that would be needed to maintain the yard connections
2. Tunneling under Squires Bridge, particularly trying to thread a needle between the support pillars -- I think there's a path but...

I double checked the support pillars, and mapped them below:

The pillar locations are best guesses, based on Google 3D satellite, street views (north of bridge, underneath bridge, south of bridge), and this front view video of the Union Square branch.

Here's a Google Maps link with all of the above.

The yellow lines show a possible Urban Ring tunnel. This should allow a maximum width of likely about 45-50 ft (at least 40 ft) between pillars 2 and 4, well above the 33 ft width that GLX and Fitchburg ROWs have (at their narrowest points that I can find).

Spoiler: How did I determine the locations of pillars?

Pillars 1, 2, 3, 6, 7, 8 can be seen using Google 3D satellite views (south, north):

Pillar 4 sits between the WB and EB Green Line tracks (as seen from the video), so their intersection with McGrath determines its location. (In fact, this is likely the reason why the two GL tracks diverge when approaching the bridge, and why EB Green Line makes a slight turn left under the bridge before starting the ascent.) This street view also shows that relative to the bridge, 4 is slightly west of 6.

Pillar 5 is perpendicular to pillar 3 as seen from street view. The street view and video also confirm that pillar 5 is right next to Fitchburg EB (which confirms its location), and show that Grand Junction merges with Fitchburg EB at or just before pillar 5, so I used that to estimate GJ's track.

Spoiler: Potential impacts of pillar 6 on a WB spur of Union Square branch

@Riverside proposed a way to create a WB Lechmere -> Grand Junction branch, by diverging just east of the bridge and digging a short tunnel that turns south:

Pillar 6 kind of blocks this proposal. Looking at street view, it's not clear whether there's enough space between the current WB tracks and pillar 6 for a spur and subsequently a portal. If there is, it's probably barely enough.

If the spur goes to the north of pillar 6, looks like you will need to run a short stretch on this part of Somerville Ave Extension around the corner of pillar 6, then put a portal on the same road. However, this will necessitate closing this stretch of Somerville Ave Extension, and I'm not sure if the bottleneck at pillat 6 has enough width.
Note that whatever you do, you can't cut off the narrow path between current WB tracks and the building to the north, which leads to parking lots for the building and possibly an entrance.


[Aside] Looking at Riverside's post above (linking East Somerville tracks to Union Square tracks), it appears that if you can cut off a few more parking spots from the building, you can still fit a 82' curve to the SB Medford branch track:

Without touching the triangular parking lots, you would fall way short of the curve radius, anyway. So there doesn't seem to be a scenario where you end up linking NB Medford to WB Union Square: it's either in the correct orientation or bust.

 

[Teban54]

Anyway, the point of revisiting this discussion is that I wanted to consider yet another alternative Urban Ring routing between Sullivan and Kendall.

So far, we have:

• The traditional routing, via Grand Junction and Green Line Maintenance Facility (GLMF)
  • Need a way to go across Squires Bridge and GLMF
  • Many proposals, such as this one from Riverside (I may add more proposals to this post later)
• @Riverside 's alternative routing, via East Somerville and an infill interchange with the Union Square branch
  • Original post here, refined approach with short tunnel here

But here's another thought. I know it's probably a bad proposal - and I'm ready for people to call it as such - but:

High-level description:

• From Grand Junction, turn to Binney St and then Edwin H Land Blvd, where trains run either in a viaduct or on the surface (with dedicated ROWs from a road diet)
• Build "Lechmere" station at the intersection with GLX, with a long out-of-station transfer (900')
• Turn towards Commuter Rail ROW near Gilmore Bridge, and get to Sullivan using a combination of non-revenue tracks and/or viaducts

The primary goal and motivation: Connect Urban Ring to the Lechmere area.

• Of course, what we hope is a connection to both GLX branches. This is important for Urban Ring, but the GLMF alignment makes it impossible. The East Somerville alignment achieves this, but requires two close stops on Urban Ring and an infill on the Union Square branch.
• However, let's be real: Even in my proposal, the transfer to GL Lechmere is very far. At 900', it's longer than the State walkway (about 700' from my best guess), and on par with a would-be walkway from Copley to Back Bay (860'). It's also very challenging to build a transfer behind "paid" areas.
• But there's another benefit: Serving the developments around Lechmere. There are already many residential and office buildings, with likely more to come thanks to GLX. It's as much of a destination node as a transfer node.

Other benefits:

• Bringing rail to overly wide streets. Binney St and Land Blvd are both too wide and unfriendly to pedestrians by Cambridge standards, and putting rail either above or along them is a good opportunity to redesign them into urban boulevards.
  • My preference is a viaduct along the entire stretch, but obviously that would greatly increase the cost, so surface running is also an alternative. Fortunately, both roads definitely have room for transit lanes, but I'm concerned with the number of crossings on Binney St (and the expected amount of pedestrians).
  • Taking away lanes from Gilmore Bridge may be hard due to its traffic volumes, but in the Silver Line Extension Alternatives Analysis, Alt 5 runs via Gilmore Bridge and "almost the entirety of this alternative would operate on dedicated bus lanes". So it's not without precedent.
• A station at Binney/Third to serve the northern part of Kendall, massively increasing catchment. Binney St hosts many labs and offices, which is partially why EZ-Ride goes there, and is also much closer to the apartments in East Cambridge.
• Avoids any tunneling, since both the GLMF and East Somerville alignments will likely require a short tunnel (and the former needs to cut through Brickbottom Junction).
  • However, the potential need for viaducts may make this point moot.

Obviously, there are significant drawbacks:

• Longest route and traveling time. It also has the greatest number of grade crossings by far.
  • GLMF: 1.92 miles from Sullivan to Main St, 4 grade crossings north of Main St (some of them can be eliminated with a viaduct in East Cambridge)
  • East Somerville: 2.00 miles, 5 grade crossings (via Fitchburg St tunnel)
  • Land & Binney: 2.41 miles, surface running has 8 grade crossings
    • 2 other intersections do not allow either cars or pedestrians to cross today (Binney/5th and Land/Rogers), but may need to be brought back if we're talking about an urban transformation
    • A long viaduct can possibly bypass all of these
• (Potential) lack of cost savings from using existing railroad ROWs. That's the reason why GLMF is the standard for Urban Ring crayon proposals in the first place. My proposal basically requires greenfield ROW from Gilmore Bridge all the way to Kendall.
• Lack of track connection to Green Line (revenue or non-revenue). This can introduce operational challenges, and make a phased build less plausible.
• Potential opposition to viaducts from condos along Land Blvd.

Edit: Discussion continued here, a few comments below, due to character limit.

 

[Charlie_mta]

Anyway, the point of revisiting this discussion is that I wanted to consider yet another alternative Urban Ring routing between Sullivan and Kendall.

So far, we have:

• The traditional routing, via Grand Junction and Green Line Maintenance Facility (GLMF)
  • Need a way to go across Squires Bridge and GLMF
  • Many proposals, such as this one from Riverside (I may add more proposals to this post later)
• @Riverside 's alternative routing, via East Somerville and an infill interchange with the Union Square branch
  • Original post here, refined approach with short tunnel here

But here's another thought. I know it's probably a bad proposal - and I'm ready for people to call it as such - but:
View attachment 43925

High-level description:

• From Grand Junction, turn to Binney St and then Edwin H Land Blvd, where trains run either in a viaduct or on the surface (with dedicated ROWs from a road diet)
• Build "Lechmere" station at the intersection with GLX, with a long out-of-station transfer (900')
• Turn towards Commuter Rail ROW near Gilmore Bridge, and get to Sullivan using a combination of non-revenue tracks and/or viaducts

The primary goal and motivation: Connect Urban Ring to the Lechmere area.

• Of course, what we hope is a connection to both GLX branches. This is important for Urban Ring, but the GLMF alignment makes it impossible. The East Somerville alignment achieves this, but requires two close stops on Urban Ring and an infill on the Union Square branch.
• However, let's be real: Even in my proposal, the transfer to GL Lechmere is very far. At 900', it's longer than the State walkway (about 700' from my best guess), and on par with a would-be walkway from Copley to Back Bay (860'). It's also very challenging to build a transfer behind "paid" areas.
• But there's another benefit: Serving the developments around Lechmere. There are already many residential and office buildings, with likely more to come thanks to GLX. It's as much of a destination node as a transfer node.

Other benefits:

• Bringing rail to overly wide streets. Binney St and Land Blvd are both too wide and unfriendly to pedestrians by Cambridge standards, and putting rail either above or along them is a good opportunity to redesign them into urban boulevards.
  • My preference is a viaduct along the entire stretch, but obviously that would greatly increase the cost, so surface running is also an alternative. Fortunately, both roads definitely have room for transit lanes, but I'm concerned with the number of crossings on Binney St (and the expected amount of pedestrians).
  • Taking away lanes from Gilmore Bridge may be hard due to its traffic volumes, but in the Silver Line Extension Alternatives Analysis, Alt 5 runs via Gilmore Bridge and "almost the entirety of this alternative would operate on dedicated bus lanes". So it's not without precedent.
• A station at Binney/Third to serve the northern part of Kendall, massively increasing catchment. Binney St hosts many labs and offices, which is partially why EZ-Ride goes there, and is also much closer to the apartments in East Cambridge.
• Avoids any tunneling, since both the GLMF and East Somerville alignments will likely require a short tunnel (and the former needs to cut through Brickbottom Junction).
  • However, the potential need for viaducts may make this point moot.

Obviously, there are significant drawbacks:

• Longest route and traveling time.It also has the greatest number of grade crossings by far.
  • GLMF: 1.92 miles from Sullivan to Main St, 4 grade crossings north of Main St (some of them can be eliminated with a viaduct in East Cambridge)
  • East Somerville: 2.00 miles, 5 grade crossings (via Fitchburg St tunnel)
  • Land & Binney: 2.41 miles, surface running has 8 grade crossings
    • 2 other intersections do not allow either cars or pedestrians to cross today (Binney/5th and Land/Rogers), but may need to be brought back if we're talking about an urban transformation
    • A long viaduct can possibly bypass all of these
• (Potential) lack of cost savings from using existing railroad ROWs. That's the reason why GLMF is the standard for Urban Ring crayon proposals in the first place. My proposal basically requires greenfield ROW from Gilmore Bridge all the way to Kendall.
• Lack of track connection to Green Line (revenue or non-revenue). This can introduce operational challenges, and make a phased build less plausible.
• Potential opposition to viaducts from condos along Land Blvd.

More edits coming later.

One sub-option would be to run the new line up Rutherford Ave instead of next to the OL, and provide a station on Rutherford Ave just west of Austin St to provide part of Charlestown with walkable access.

 

[Teban54]

One sub-option would be to run the new line up Rutherford Ave instead of next to the OL, and provide a station on Rutherford Ave just west of Austin St to provide part of Charlestown with walkable access.

That's an interesting choice too! My concern would be how you get back to the Eastern Route ROW, and how you place a Sullivan station that still has good transfers to the Orange Line.

Once you get on Rutherford, there's not really a good place to merge back to OL until Sullivan itself. Depending on alignment, your station at Sullivan can possibly end up being too far from OL. A surface-running route may also take too much time through the many intersections there (especially given the number of potential grade crossings it already has south of Lechmere).

North of Sullivan, there's no room to expand the ROW east of the Rockburyport tracks, as they're adjacent to Sherman St and this building. So you need to either move OL and Rockburyport tracks west to take over the current GJ ROW, or have Urban Ring cross over to the west only to cross OL again immediately after. Another option is to run on Alford St and Lower Broadway, but it faces similar challenges with ROW, grade separation and Sullivan station placement, if not worse.

 

[TheRatmeister]

That's an interesting choice too! My concern would be how you get back to the Eastern Route ROW, and how you place a Sullivan station that still has good transfers to the Orange Line.

Once you get on Rutherford, there's not really a good place to merge back to OL until Sullivan itself. Depending on alignment, your station at Sullivan can possibly end up being too far from OL. A surface-running route may also take too much time through the many intersections there (especially given the number of potential grade crossings it already has south of Lechmere).

North of Sullivan, there's no room to expand the ROW east of the Rockburyport tracks, as they're adjacent to Sherman St and this building. So you need to either move OL and Rockburyport tracks west to take over the current GJ ROW, or have Urban Ring cross over to the west only to cross OL again immediately after. Another option is to run on Alford St and Lower Broadway, but it faces similar challenges with ROW, grade separation and Sullivan station placement, if not worse.

I'll just throw my hat in the ring here and say I'm not sure an urban ring route should be trying to string together random bits of surface ROWs through the city, I think they're too limiting in this case. I'd say an ring line should look like Copenhagen's M3/M4, with a fully bored underground route running small automated trains at high frequencies, since the line would be used for a lot of smaller journeys involving transfers, so minimizing the amount of time spent waiting for a train is more important here than aiming for full RL/OL sized trains. Given the size of the project, the fixed costs of a bored tunnel such as the TBM(s) required don't impact the cost per mile nearly as much, and the freedom of a bored route deeper underground allows for a good chunk of the soil/utilities problems immediate underneath the streets to be bypassed, and gives flexibility for deciding a route.

 

[Teban54]

I'll just throw my hat in the ring here and say I'm not sure an urban ring route should be trying to string together random bits of surface ROWs through the city, I think they're too limiting in this case. I'd say an ring line should look like Copenhagen's M3/M4, with a fully bored underground route running small automated trains at high frequencies, since the line would be used for a lot of smaller journeys involving transfers, so minimizing the amount of time spent waiting for a train is more important here than aiming for full RL/OL sized trains. Given the size of the project, the fixed costs of a bored tunnel such as the TBM(s) required don't impact the cost per mile nearly as much, and the freedom of a bored route deeper underground allows for a good chunk of the soil/utilities problems immediate underneath the streets to be bypassed, and gives flexibility for deciding a route.

Well, to be honest, I'm a fan of TBM tunnels for the most part. But the reasons why most people here don't suggest a fully TBM-ed Urban Ring are:

• Cost concerns (especially for the US and Boston - see costs for Red-Blue)
• Existing railroad ROWs for the northern half from BL Airport to BU Bridge, via Eastern Route and Grand Junction, which also forms the ideal route for northern Urban Ring
  • Current grade crossings on Eastern Route can be eliminated, will need to be for 15-min Regional Rail frequencies, and IIRC there are actual plans for them
• Crossing Kendall and Red Line, where @F-Line to Dudley has repeatedly said that a tunnel under RL will likely be very costly due to flooding mitigations (unless you tunnel all the way across the Charles towards BU, I think)
  • I found this and this; both comments are in context of a Regional Rail tunnel via Grand Junction, but I think most arguments still apply for a LRT tunnel except that you can have steeper grades

So for the northern Urban Ring, it seems much more cost-effective to utilize the railroad ROWs for surface routes, and deal with grade separation as much as possible using viaducts and open cuts. Even in my Binney & Land proposal above, you'll notice that I worded it in favor of an El and treated street-running as a compromise. With maximum grade separation, you can probably achieve the same reliability as a TBM tunnel while saving cost.

Now, as for southern Urban Ring, I fully agree with you. To hit the main destinations (BU, Longwood, Ruggles, Nubian, BMC, somewhere on the Red Line, Seaport, and preferably back to Logan), there are virtually no good ROWs. This might be where TBM tunnels give you much better route and service than trying C&C under the street grids (that give windy routes like this), or even running surface LRT/BRT that you'll see in a lot of "dollar store" proposals on this forum.

A cross-Longwood tunnel is where I think a deep-bored tunnel will see the greatest benefits, assuming it's feasible. If there's one rapid transit (i.e. non-NSRL) TBM tunnel in the city that's worth going big on, I think that's it. F-Line has also spoken against feasibility in the past, but I dunno.

FYI, I think the default assumption here is for Urban Ring to be built (or at least start off) as light rail with short headways, instead of heavy rail.

 

[Teban54]

But here's another thought. I know it's probably a bad proposal - and I'm ready for people to call it as such - but:
View attachment 43925

High-level description:

• From Grand Junction, turn to Binney St and then Edwin H Land Blvd, where trains run either in a viaduct or on the surface (with dedicated ROWs from a road diet)
• Build "Lechmere" station at the intersection with GLX, with a long out-of-station transfer (900')
• Turn towards Commuter Rail ROW near Gilmore Bridge, and get to Sullivan using a combination of non-revenue tracks and/or viaducts

[...]

A summary table comparing the three alignments:

Alignment	GLMF	East Somerville	Binney & Gilmore
Length and Speed	Good Shortest route (1.92 mi) 4 grade crossings 1 stop Fastest (gentle curves)	Medium Slightly longer (2.00 mi) 4 grade crossings 2 stops Medium speed (several curves near East Somerville and McGrath)	Medium for a viaduct, Bad for surface Longest route (2.41 mi) 8 grade crossings 2 stops (corrected) Slowest speed (primarily due to route length and possible grade crossings)
Ridership and Transfers	Bad Low catchment (1 stop at Cambridge St and/or Twin City Plaza) No GLX transfer No Lowell transfer	Medium to Good Medium catchment (Twin City Plaza (McGrath) and East Somerville) Easy GLX transfers Possible Lowell transfer (via East Somerville infill)	Medium to Good High catchment (Lechmere and Kendall North) GLX transfer, but long walk No Lowell transfer
Feasibility and Cost	Medium to Good Tricky infrastructure (Brickbottom Junction) Reuse most surface railroad ROWs Short tunnel likely required Reconfigurations for GLMF and CRMF needed Politically feasible	Medium to Good (without Brickbottom connection) No major difficulties Reuse most surface railroad ROWs, but may need viaduct over Yard 10 lead Short tunnel required No or less impacts to GLMF and CRMF Politically feasible	Medium for a viaduct, Good for surface No major difficulties Greenfield ROW No tunnels, but may need long viaducts No impacts to GLMF and CRMF May face political challenges (Land Blvd El, Gilmore Bridge)
Operational Flexibility	Good Easy access to Green Line and GLMF Possible Phase 1 for GJ service (as GL branch)	Medium Can access GLMF, but tedious GJ Phase 1 less likely	Bad No access to Green Line and GLMF GJ Phase 1 unlikely

Spoiler: Feasibility of Binney & Gilmore Alignment

I'll primarily focus on the section between Gilmore Bridge and Sullivan. South of Gilmore Bridge, there doesn't seem to be major engineering challenges. The curve from Binney St to Land Blvd is doable with 82' radius.

Heading north, whether coming from an El over Gilmore or surface transit lanes, we will enter the Commuter Rail ROW at higher elevation. So building a viaduct above the CR tracks all the way till Grand Junction may be an option... But let's see if there are less costly ones.

There are a few non-revenue tracks within the ROW:

Yellow, cyan and lime green indicate non-revenue tracks that do not appear to be related (or at least not crucial) to the CR Maintenance Facility.

I'll admit: I have no idea what functions they serve today, and whether they are still needed for freight operations. I've found earlier proposals like this one from ceo (with a separate comment about Yard 10 lead) and this one from F-Line that still preserved several tracks near Grand Junction for freight, but not specific to this ROW. So feel free to educate me.

I'll make a best guess that the cyan tracks are more likely to be free. Luckily, that also gives us the easiest proposal:

Here, Urban Ring will land directly on the cyan tracks after making the turn from Gilmore Bridge. It needs to cross the Rockburyport tracks, but there's more than enough room to go either above or below them (in a shallow open cut for the latter). You can cross the GJ-Rockburyport connection tracks the same way, then either land on the 2-track Grand Junction to Sullivan, or go even further west if you want to preserve the wye to the north as in F-Line's proposal.

If we can (only) take the yellow tracks instead, it's a bit more tedious, but you can still get the following:

The existing yellow track has a single-track bottleneck between CRMF and the Lowell Line tracks, but it may still be salvageable. The trick here is, there's a small gap between Lowell and Rockburyport tracks, as the former rises up for an overpass across Grand Junction (seen here). I think (but am not sure) we can shift the Lowell tracks further north where the bottleneck is, and then have it come back to the overpass as it gets closer. This opens up room to double track the yellow track at grade north of CRMF.

South of CRMF, you may have to cross from west of Lowell to east of the cyan tracks, the only "free spot" in this area. Perhaps it might even be possible to just build above the CRMF leads to avoid the back-and-forth, but I don't see a good place for support columns.

In case we can't touch either cyan or yellow tracks, there may still be a way that "threads the needle":

To be honest, I'm not sure if this is actually feasible... But it's basically taking whatever gaps we can find: east of the cyan tracks near Gilmore bridge, between yellow tracks and Lowell, then east of Rockburyport.

 

[TheRatmeister]

Well, to be honest, I'm a fan of TBM tunnels for the most part. But the reasons why most people here don't suggest a fully TBM-ed Urban Ring are:

• Cost concerns (especially for the US and Boston - see costs for Red-Blue)

Any urban ring project will need substantial cost control measures implemented, regardless of the tunneling method, and any urban ring project will be extremely expensive just because of the scale. With that along with the importance of the project in mind, I do not think that design decisions should immediately compromise on the route because of cost concerns. The route should make the most important connections, and if there's existing infrastructure to use then that's a nice bonus, not a prerequisite.

• Existing railroad ROWs for the northern half from BL Airport to BU Bridge, via Eastern Route and Grand Junction, which also forms the ideal route for northern Urban Ring
  • Current grade crossings on Eastern Route can be eliminated, will need to be for 15-min Regional Rail frequencies, and IIRC there are actual plans for them

Is it really the ideal urban ring route? Going a bit further out, more following the 66 route, could allow for areas like Allston to be included. And then there's the Grand Junction. Everyone always likes to dream about rapid transit over it, but what would that look like? Obviously the line would need to be double tracked and grade-seperated, most likely in the form of trenching it given that it passes under/through some buildings, and new stations would need to be built underground in a way that avoids demolishing a bunch of buildings on the surface, likely somewhat deep. By the time we're this far, why are we even using the Grand Junction in the first place? Why burden the construction of the project by forcing it along a route that frankly isn't even that good when we're basically building 80% of a bored tunnel subway anyways? I will say though, once you reach Sullivan the argument for popping above ground to cross the Mystic into Everett or Chelsea is much stronger, and given that the best route through Everett would be right under Broadway, if that can be done cut and cover that's obviously a nice bonus.

• Crossing Kendall and Red Line, where @F-Line to Dudley has repeatedly said that a tunnel under RL will likely be very costly due to flooding mitigations (unless you tunnel all the way across the Charles towards BU, I think)
  • I found this and this; both comments are in context of a Regional Rail tunnel via Grand Junction, but I think most arguments still apply for a LRT tunnel except that you can have steeper grades

Lots of the urban ring would be challenging from a flood perspective, especially the portion near the airport. But as I said, I think a tunnel across the river makes more sense anyways, and it seems that avoids most of the immediate problems.

FYI, I think the default assumption here is for Urban Ring to be built (or at least start off) as light rail with short headways, instead of heavy rail.

I'll just be blunt here, I think that's a stupid assumption. Orbital light rail often suffers from its own success, with the inherently limited capacity of tram-like vehicles hamstringing rapid transit service. Look no further than the GL today to see why that's a problem. Not to mention that grade separation will be necessary, across the entire route, for headways to be short, consistent, and generally well suited for the service provided. That's the hard part of building any transit, and the only reason why light-rail should be considered in this context (IMO) is to allow for at-grade street/median running and local service, neither of which suit a subway line and would severely constrain any conversion attempts in the future. If we're already building a new right-of-way, let's run a metro or light-metro on it.

 

[F-Line to Dudley]

Any urban ring project will need substantial cost control measures implemented, regardless of the tunneling method, and any urban ring project will be extremely expensive just because of the scale. With that along with the importance of the project in mind, I do not think that design decisions should immediately compromise on the route because of cost concerns. The route should make the most important connections, and if there's existing infrastructure to use then that's a nice bonus, not a prerequisite.

What about the rail ROW's compromises the routing??? The UR was subject to a Major Investment Study that ID'd the stops that would haul in the most ridership and capture the most transfers from other modes, and that study did not leave any huge catchments on the table. You're going to have to square your preference for an off-ROW routing with the MIS results. This isn't crayon vs. crayon; there's meaty study results informing the routing choice, and a large consensus on the general routing vis-a-vis stop selection.

Is it really the ideal urban ring route? Going a bit further out, more following the 66 route, could allow for areas like Allston to be included. And then there's the Grand Junction. Everyone always likes to dream about rapid transit over it, but what would that look like? Obviously the line would need to be double tracked and grade-seperated, most likely in the form of trenching it given that it passes under/through some buildings, and new stations would need to be built underground in a way that avoids demolishing a bunch of buildings on the surface, likely somewhat deep. By the time we're this far, why are we even using the Grand Junction in the first place? Why burden the construction of the project by forcing it along a route that frankly isn't even that good when we're basically building 80% of a bored tunnel subway anyways? I will say though, once you reach Sullivan the argument for popping above ground to cross the Mystic into Everett or Chelsea is much stronger, and given that the best route through Everett would be right under Broadway, if that can be done cut and cover that's obviously a nice bonus.

Again...the 66 didn't chunk out in the MIS to the mega ridership nodes that following the rail ROW's did. If you want that as an alternative, you have to show the math on the cost-benefit.

The GJ is a double-track ROW...that's trivial. And all of the grade crossings excepting Main & Broadway are trivial eliminations on LRT with rail-over-road bridges...no trenching needed. Being able to share signal cycles at Main and Broadway inoculates the worst of the traffic impacts, as the trolleys would just get a dedicated phase in the overall churn. I'm not sure where you're getting the idea that punitive tunneling is needed here. This was studied.

I'll just be blunt here, I think that's a stupid assumption. Orbital light rail often suffers from its own success, with the inherently limited capacity of tram-like vehicles hamstringing rapid transit service. Look no further than the GL today to see why that's a problem. Not to mention that grade separation will be necessary, across the entire route, for headways to be short, consistent, and generally well suited for the service provided. That's the hard part of building any transit, and the only reason why light-rail should be considered in this context (IMO) is to allow for at-grade street/median running and local service, neither of which suit a subway line and would severely constrain any conversion attempts in the future. If we're already building a new right-of-way, let's run a metro or light-metro on it.

HRT doesn't do branching as well as LRT does, and the MIS-studied Urban Ring did have 2 branches: a Harvard Square spur off the BU Bridge junction and a JFK/UMass spur off of Nubian Sq. The patterns would be mixed and overlapping to capture the full spectrum of destination pairs. It's not intended as a uni-line route, because hardly anyone is going to be riding it from end-to-end; the destination pairs take big dumps at roughly the quadrant points on the map. For mixing and matching it's hard to do better than flexible LRT. We've spent pages and pages in the Green Line Reconfig thread putting those patterns into a blender and interfacing them with a capacity-expanded, double-trunked greater Green Line. The possibilities are almost endless on that mode.

 

[Teban54]

For this comment only, I'm limiting the scope to northern half of Urban Ring - keep in mind, that's like 50% of the whole route.

And then there's the Grand Junction. Everyone always likes to dream about rapid transit over it, but what would that look like? Obviously the line would need to be double tracked and grade-seperated, most likely in the form of trenching it given that it passes under/through some buildings, and new stations would need to be built underground in a way that avoids demolishing a bunch of buildings on the surface, likely somewhat deep. By the time we're this far, why are we even using the Grand Junction in the first place? Why burden the construction of the project by forcing it along a route that frankly isn't even that good when we're basically building 80% of a bored tunnel subway anyways?

The two bolded parts are not equivalent. A double-tracked and completely grade-separated ROW can run service just as effectively regardless of whether it's at the surface, in a subway (C&C or TBM), or in an elevated structure like these.

And the first bolded part is not exactly obvious. If you can afford, say, 1-2 grade crossings in a way that hugely reduces the cost, then as long as you're still running light rail, those 1-2 grade crossings don't significantly reduce your reliability. That basically describes Grand Junction. Main St is a constraint as you have buildings above and Red Line below, but to the north, you can start rising into a viaduct or descending into a tunnel or trench, however you wish.

Grand Junction is the most popular choice not just because it's already there, but because it connects Kendall, one of the biggest employment centers outside of the downtown core. Looking at how many people dream of BLX to Kendall only reinforces this idea. And it also nicely brings you to Sullivan, a major transit hub that's at the doorsteps of Kendall and begging for a one-seat ride.

I'm by no means married to Grand Junction (which is why I made the Binney & Gilmore proposal in the first place). But for the purpose of bringing Urban Ring to Kendall, I honestly think an almost-grade-separated surface light rail line with a single grade crossing at Main St offers the best service-cost tradeoff, by far.

I know you're asking... Why Kendall?

Is it really the ideal urban ring route? Going a bit further out, more following the 66 route, could allow for areas like Allston to be included.

Most Urban Ring proposals that use Grand Junction - both crayons and the official Urban Ring study - do have a spur from Harvard that goes south to meet the ring, most frequently via West Station. That can take care of Allston with simple changes.

Yes, Harvard is another major transit hub and commercial destination. And yes, going from Sullivan to Harvard doesn't require as much engineering headache as crossing under the Red Line in the flood-prone area that's Kendall. But Harvard-Sullivan is still not trivial either, and a comparison needs to be made between tunneling through the entire Sullivan-Harvard-(somewhere near BU and Allston) and likely much cheaper ways of Sullivan-Kendall-BU Bridge with a single grade crossing.

I'm not saying "Kendall good, Harvard bad", but unless you're dead set on total grade separation, the benefits that Harvard brings need to be bigger than Kendall to justify the cost. I don't know the answer myself, but the studies that F-Line mentioned above seem to imply that's not the case. This map that Riverside mentioned also shows that while they're both notable employment centers outside of downtown, Kendall seems to provide more jobs:

Bottom line is, Kendall vs Harvard is a question that needs detailed analyses, and neither should be discounted completely.

Lots of the urban ring would be challenging from a flood perspective, especially the portion near the airport. But as I said, I think a tunnel across the river makes more sense anyways, and it seems that avoids most of the immediate problems.

The problem isn't tunneling under the river, it's tunneling under the old Red Line tunnel in a flood-prone area that Kendall is.

Even for the river crossing itself, while I'm not opposed to a tunnel under the Charles, there is already existing rail infrastructure across the river: the BU bridge.

I'll just be blunt here, I think that's a stupid assumption. Orbital light rail often suffers from its own success, with the inherently limited capacity of tram-like vehicles hamstringing rapid transit service. Look no further than the GL today to see why that's a problem. Not to mention that grade separation will be necessary, across the entire route, for headways to be short, consistent, and generally well suited for the service provided. That's the hard part of building any transit, and the only reason why light-rail should be considered in this context (IMO) is to allow for at-grade street/median running and local service, neither of which suit a subway line and would severely constrain any conversion attempts in the future. If we're already building a new right-of-way, let's run a metro or light-metro on it.

You might be misinterpreting what I implied by Urban Ring being light rail. I was saying most people imagine it will use light rail vehicles akin to GL Type 10s. I was not saying most people want Urban Ring to be a glorified streetcar route running in street medians like the B, C and E branches are.

I think there's a general consensus that Urban Ring, at least in its "final" form, should have as much grade separation as possible. But I think it's reasonable to start off with light rail vehicles running on a mostly "heavy metro" route, if there are a handful places where grade separations may not be achievable yet (e.g. Main St in Kendall). Especially when you factor in the operational flexibility with the Green Line (and a potential future Huntington Ave subway as part of a reconfigured GL system), as F-Line mentioned above. And if we're designing Urban Ring from scratch without being limited to Green Line's platform lengths, you can increase capacity by running longer train sets where possible.

Given the current political climate for transit, it's probably better to have something up and running first (as long as they do provide good grade separation initially even if not perfect). In the event that Urban Ring does become that much of a success (which I certainly hope!) that it's worth converting to heavy rail at the cost of separating from the Green Line system, then we can figure out the last few pieces of grade separations (which do include viaducts like the ones I proposed).

(While that means we may end up having to revisit grade separation through Kendall again, if the cost will be there regardless, I think it will be much more feasible to leave the problem for the future, rather than having to figure it out on day 1 and potentially killing the project. And I mean, some people did propose an El on Vassar St.)

I'll conclude by saying this: I want to see more heavy rail systems not just in Boston, but across the US. I really do. But the trend of brand new transit lines across the nation generally lean more towards light rail than heavy rail.

 

[TheRatmeister]

Again...the 66 didn't chunk out in the MIS to the mega ridership nodes that following the rail ROW's did. If you want that as an alternative, you have to show the math on the cost-benefit.

What about the rail ROW's compromises the routing??? The UR was subject to a Major Investment Study that ID'd the stops that would haul in the most ridership and capture the most transfers from other modes, and that study did not leave any huge catchments on the table. You're going to have to square your preference for an off-ROW routing with the MIS results. This isn't crayon vs. crayon; there's meaty study results informing the routing choice, and a large consensus on the general routing vis-a-vis stop selection.

The route is only the best if you do what (it seems as far as I can tell) the study did and ignore places like Coolidge Corner, Brookline Village, Brighton, Cambridgeport, etc. If we don't ignore those places, I'd be quite surprise if the answer is exactly the same. The other thing to consider is that the study really focused on BRT as the mode choice, because 2000s. (And it still wasn't cheap) If we don't make that assumption right out of the gate, some of the design choices make way less sense, like essentially paralleling the OL between Community College and Wellington, and some extra squiggly and double-backed service patterns to Union Sq. (Also, most of the "BRT" they propose runs in mixed traffic, which then makes it not BRT. Like I said, 2000s things.)

HRT doesn't do branching as well as LRT does, and the MIS-studied Urban Ring did have 2 branches: a Harvard Square spur off the BU Bridge junction and a JFK/UMass spur off of Nubian Sq. The patterns would be mixed and overlapping to capture the full spectrum of destination pairs. It's not intended as a uni-line route, because hardly anyone is going to be riding it from end-to-end; the destination pairs take big dumps at roughly the quadrant points on the map. For mixing and matching it's hard to do better than flexible LRT. We've spent pages and pages in the Green Line Reconfig thread putting those patterns into a blender and interfacing them with a capacity-expanded, double-trunked greater Green Line. The possibilities are almost endless on that mode.

And? We're not trying to build a city-wide tram network here, we're trying to build an orbital line. The first one would definitely be nice, but it's not the priority here. This image from the MIS study shows quite nicely I think that you do not need much branching to hit basically all the major points of interest.

As a side-note, I didn't mention the other major problem with using the Grand Junction, which is that now there isn't a (somewhat) good rail link between North Station and South Station for things like rolling stock transfers, which means that unless NSRL happens as far as I can tell any reuse of the alignment is dead in the water. If NSRL does happen, I think reusing the route as a busway/bike path/linear park actually makes more sense than rail service, as this is an area where feeding many local buses into enhanced local stops for the MIT campus and bajillion lab buildings nearby would make more sense then a couple consolidated stops.

 

[Riverside]

Ugh this is such an excellent discussion, so many things I want to reply to, let's see what I can get to... [this has not been proofread]

I double checked the support pillars, and mapped them below

This is excellent work, and is incredibly useful for all the wacky discussions we have here. And it's pleasant to see that the straight-shot alignment could actually be the most parsimonious! Certainly it looks the prettiest on the map.

@Riverside proposed a way to create a WB Lechmere -> Grand Junction branch, by diverging just east of the bridge and digging a short tunnel that turns south:

[snip]
Pillar 6 kind of blocks this proposal. Looking at street view, it's not clear whether there's enough space between the current WB tracks and pillar 6 for a spur and subsequently a portal. If there is, it's probably barely enough.

Yes, good catch. The exact alignment of a spur off of the Union WB branch has a lot of open questions around it. I generally assume that potentially all of Somerville Ave Extension under the bridge might eventually be reclaimed for a transit ROW; either way, a spur branching off between pillars 4 and 6 could, I think, potentially thread the needle needed here.

Looking at Riverside's post above (linking East Somerville tracks to Union Square tracks), it appears that if you can cut off a few more parking spots from the building, you can still fit a 82' curve to the SB Medford branch track

Thank you for looking more closely at this.

But here's another thought. I know it's probably a bad proposal - and I'm ready for people to call it as such - but:

High-level description:

• From Grand Junction, turn to Binney St and then Edwin H Land Blvd, where trains run either in a viaduct or on the surface (with dedicated ROWs from a road diet)
• Build "Lechmere" station at the intersection with GLX, with a long out-of-station transfer (900')
• Turn towards Commuter Rail ROW near Gilmore Bridge, and get to Sullivan using a combination of non-revenue tracks and/or viaducts

I like the thinking, particularly for its effort to break out of the mold of "Grand Junction or bust" -- not that the Grand Junction alt needs to be jettisoned or anything, just that the extra perspective is always valuable to make sure we are checking our underlying assumptions.

One notion to consider: you could make this a branch that coexists with either the GLMF or East Somerville alignment (especially if you took @Charlie_mta's suggestion and instead routed it through Charlestown proper). Some more thoughts on this idea below.

I'll just throw my hat in the ring here and say I'm not sure an urban ring route should be trying to string together random bits of surface ROWs through the city, I think they're too limiting in this case. I'd say an ring line should look like Copenhagen's M3/M4, with a fully bored underground route running small automated trains at high frequencies, since the line would be used for a lot of smaller journeys involving transfers, so minimizing the amount of time spent waiting for a train is more important here than aiming for full RL/OL sized trains. Given the size of the project, the fixed costs of a bored tunnel such as the TBM(s) required don't impact the cost per mile nearly as much, and the freedom of a bored route deeper underground allows for a good chunk of the soil/utilities problems immediate underneath the streets to be bypassed, and gives flexibility for deciding a route.

While I ultimately agree with @Teban54's conclusions later on, I do want to say that I think this is a really important perspective to continue to keep in mind. It's way too easy to fall prey to "building where it seems easy" instead of "building where it's needed", and in general I think we actually need to dream bigger with our proposals -- capture the imagination of the public, that kind of thing. To wit:

So for the northern Urban Ring, it seems much more cost-effective to utilize the railroad ROWs for surface routes, and deal with grade separation as much as possible using viaducts and open cuts. Even in my Binney & Land proposal above, you'll notice that I worded it in favor of an El and treated street-running as a compromise. With maximum grade separation, you can probably achieve the same reliability as a TBM tunnel while saving cost.

Bottom line, I agree with you. But I am increasingly wary of the idea that "Urban Ring = Grand Junction". The Grand Junction was a freight railroad, and it accordingly runs away from where people live, especially northeast of Sullivan. It looks super tempting because there is this uninterrupted ROW that runs from Airport to Sullivan to Kendall, but I really think it's important to consider each segment carefully on its own merits.

 

[Riverside]

A summary table comparing the three alignments:

Alignment	GLMF	East Somerville	Binney & Gilmore
Length and Speed	Good Shortest route (1.92 mi) 4 grade crossings 1 stop Fastest (gentle curves)	Medium Slightly longer (2.00 mi) 4 grade crossings 2 stops Medium speed (several curves near East Somerville and McGrath)	Bad Longest route (2.41 mi) 8 grade crossings 3 stops Slowest speed (primarily due to route length and possible grade crossings)
Ridership and Transfers	Bad Low catchment (1 stop at Cambridge St and/or Twin City Plaza) No GLX transfer No Lowell transfer	Medium to Good Medium catchment (Twin City Plaza (McGrath) and East Somerville) Easy GLX transfers Possible Lowell transfer (via East Somerville infill)	Medium to Good High catchment (Lechmere and Kendall North) GLX transfer, but long walk No Lowell transfer
Feasibility and Cost	Medium to Good Tricky infrastructure (Brickbottom Junction) Reuse most surface railroad ROWs Short tunnel likely required Reconfigurations for GLMF and CRMF needed Politically feasible	Medium to Good (without Brickbottom connection) No major difficulties Reuse most surface railroad ROWs, but may need viaduct over Yard 10 lead Short tunnel required No or less impacts to GLMF and CRMF Politically feasible	Medium for a viaduct, Good for surface No major difficulties Greenfield ROW No tunnels, but may need long viaducts No impacts to GLMF and CRMF May face political challenges (Land Blvd El, Gilmore Bridge)
Operational Flexibility	Good Easy access to Green Line and GLMF Possible Phase 1 for GJ service (as GL branch)	Medium Can access GLMF, but tedious GJ Phase 1 less likely	Bad No access to Green Line and GLMF GJ Phase 1 unlikely

Excellent summary. The only points I'd disagree on is the Feasibility & Cost of the GLMF alignment and the E Somerville alignment: I would probably put GLMF at Bad to Medium because you need to tunnel under the densest part of the junction with a longer tunnel under active tracks that the East Somerville alignment's tunnel under Squires Bridge, with another tunnel west of the bridge to go from Lechmere -> Grand Junction.

The E Somerville alignment I would probably stick at Medium because you would still need to tunnel under active rails (just fewer of them) and under the bridge, and then again under the Medford Branch viaduct.

(Actually, I just realized: are you assessing the Fitchburg St alt, or the "harmonized" alt?)

I'll just be blunt here, I think that's a stupid assumption. Orbital light rail often suffers from its own success, with the inherently limited capacity of tram-like vehicles hamstringing rapid transit service. Look no further than the GL today to see why that's a problem. Not to mention that grade separation will be necessary, across the entire route, for headways to be short, consistent, and generally well suited for the service provided. That's the hard part of building any transit, and the only reason why light-rail should be considered in this context (IMO) is to allow for at-grade street/median running and local service, neither of which suit a subway line and would severely constrain any conversion attempts in the future. If we're already building a new right-of-way, let's run a metro or light-metro on it.

@Teban54's response to this is right on the money. The Urban Ring would be "light rail" in the trivial sense that it would use vehicles that can interface with the surface street environment (e.g. grade crossings), as opposed to heavy rail which simply cannot. Most of the Urban Ring would still be grade-separated, in a dedicated ROW, with high-capacity vehicles that could barely be called "streetcars". I would 100% describe the proposals as "light metro". Grade crossings would of course be kept at a minimum as much as possible, but the difference between LRT and HRT is the difference between a few difficult-to-grade-separate grade crossings killing the project or not.

 

[Riverside]

Is it really the ideal urban ring route? Going a bit further out, more following the 66 route, could allow for areas like Allston to be included. And then there's the Grand Junction. Everyone always likes to dream about rapid transit over it, but what would that look like? Obviously the line would need to be double tracked and grade-seperated, most likely in the form of trenching it given that it passes under/through some buildings, and new stations would need to be built underground in a way that avoids demolishing a bunch of buildings on the surface, likely somewhat deep. By the time we're this far, why are we even using the Grand Junction in the first place?

No. Hear me out: the Grand Junction is not the ideal Urban Ring route. I agree with you that a circumferential service would be better run further to the west in Cambridge -- Harvard is a little far, but Central would seem right on the money.

BUT the thing is... the "Urban Ring" really isn't a circumferential service proposal (despite its name and how we've been talking about it for 30 years). Really, it's an effort to build two new subnetworks: a Kendall subnetwork, and a Longwood subnetwork. And, as @Teban54 lays out, the Grand Junction is shockingly good as a north-south axis of a Kendall subnetwork. (And that branch via Binney St could be just that -- a branch.)

The UR was subject to a Major Investment Study that ID'd the stops that would haul in the most ridership and capture the most transfers from other modes, and that study did not leave any huge catchments on the table. You're going to have to square your preference for an off-ROW routing with the MIS results. This isn't crayon vs. crayon; there's meaty study results informing the routing choice, and a large consensus on the general routing vis-a-vis stop selection.

Can you lay your hands on this doc? Would be great to read.

You might be misinterpreting what I implied by Urban Ring being light rail. I was saying most people imagine it will use light rail vehicles akin to GL Type 10s. I was not saying most people want Urban Ring to be a glorified streetcar route running in street medians like the B, C and E branches are.

I think there's a general consensus that Urban Ring, at least in its "final" form, should have as much grade separation as possible. But I think it's reasonable to start off with light rail vehicles running on a mostly "heavy metro" route, if there are a handful places where grade separations may not be achievable yet (e.g. Main St in Kendall). Especially when you factor in the operational flexibility with the Green Line (and a potential future Huntington Ave subway as part of a reconfigured GL system), as F-Line mentioned above. And if we're designing Urban Ring from scratch without being limited to Green Line's platform lengths, you can increase capacity by running longer train sets where possible.

Given the current political climate for transit, it's probably better to have something start and running first (as long as they do provide good grade separation initially even if not perfect). In the event that Urban Ring does become that much of a success (which I certainly hope!) that it's worth converting to heavy rail at the cost of separating from the Green Line system, then we can figure out the last few pieces of grade separations (which do include viaducts like the ones I proposed).

(While that means we may end up having to revisit grade separation through Kendall again, if the cost will be there regardless, I think it will be much more feasible to leave the problem for the future, rather than having to figure it out on day 1 and potentially killing the project. And I mean, some people did propose an El on Vassar St.)

I'll conclude by saying this: I want to see more heavy rail systems not just in Boston, but across the US. I really do. But the trend of brand new transit lines across the nation generally lean more towards light rail than heavy rail.

Big agree on all this. When I first rode the LA Metro's light rail lines (in particular the line out to Santa Monica), it really changed my conception of what light rail can be. I think the Urban Ring would be much more like that.

The route is only the best if you do what (it seems as far as I can tell) the study did and ignore places like Coolidge Corner, Brookline Village, Brighton, Cambridgeport, etc. If we don't ignore those places, I'd be quite surprise if the answer is exactly the same.

Yeah, like I said -- I think the practical reality is that the Urban Ring isn't and never has been about serving those places -- it's been about building subnetworks for Kendall and LMA. To me, those are clearly the top priorities. Proper circumferential service is a different beast.

 

[TheRatmeister]

No. Hear me out: the Grand Junction is not the ideal Urban Ring route. I agree with you that a circumferential service would be better run further to the west in Cambridge -- Harvard is a little far, but Central would seem right on the money.

BUT the thing is... the "Urban Ring" really isn't a circumferential service proposal (despite its name and how we've been talking about it for 30 years). Really, it's an effort to build two new subnetworks: a Kendall subnetwork, and a Longwood subnetwork. And, as @Teban54 lays out, the Grand Junction is shockingly good as a north-south axis of a Kendall subnetwork. (And that branch via Binney St could be just that -- a branch.)


Can you lay your hands on this doc? Would be great to read.

Big agree on all this. When I first rode the LA Metro's light rail lines (in particular the line out to Santa Monica), it really changed my conception of what light rail can be. I think the Urban Ring would be much more like that.

Yeah, like I said -- I think the practical reality is that the Urban Ring isn't and never has been about serving those places -- it's been about building subnetworks for Kendall and LMA. To me, those are clearly the top priorities. Proper circumferential service is a different beast.

I was able to find parts of the study here, obviously the whole thing would be nice though. Anyways, I think building out stronger subnetworks is a good idea. Kendall, Longwood, Nubian, etc are all good places to do that. But the urban ring proposal doesn't do that very well either. Instead of building local transportation hubs they're used as nodes in a long, strung out, and (relatively) low capacity circumferential route. A much better place to start would be to use infrastructure like Roxbury's wide streets or Cambridge with the Grand Junction (Assuming NSRL gets built) as corridors for local service like buses and/or streetcar/tram routes, not as weird piecemeal bits of a franken-line.