Green Line Reconfiguration

I get that they're different modes, but the Green Line's Central Subway has run with, what, 40-45 TPH with the flat junction at Copley (not that that's anyone's idea of a good junction), would a junction off Worcester to serve Riverside really have that major an impact even at Regional Rail frequencies? (And it's not as if the existing CR system doesn't have any flat junctions of its own *cough*Reading Junction*cough*)
And the GL moves at 35mph
 
Riverside RR is a fever dream. A flat junction would screw up Worcester service. Using the dead space in the 128/90 interchange and a Weston infill is a much more likely outcome. In fact, it should replace Auburndale and West Newton should be moved a little west, with Newtondale moved east closer to NC

This is basically exactly what I proposed a few months ago as "Norumbega Junction" (larger discussion here).

1663159825908.png


(The diagram is a little hard to read, but the mainline has two platforms with a third passing track in between. I'm not married to that layout.)

I get that they're different modes, but the Green Line's Central Subway has run with, what, 40-45 TPH with the flat junction at Copley (not that that's anyone's idea of a good junction), would a junction off Worcester to serve Riverside really have that major an impact even at Regional Rail frequencies? (And it's not as if the existing CR system doesn't have any flat junctions of its own *cough*Reading Junction*cough*)

I'm not an expert in this, but I think differences in junction design between LRT and mainline make this apples to oranges. From what I've seen, most mainline junctions use "ladders", where trains move from track to track through a series of crossovers, while rapid transit junctions have "direct" crossovers, where the train passes through the crossed track, but doesn't actually occupy it. Crude diagram:

1663161081745.png


This means that the diverging crossing mainline train blocks both tracks for a longer period, while the LRT setup reduces conflict time.

But setting aside the flat junction problem, I prefer a transfer station on the Worcester Line directly rather than at Riverside because it allows you to maximize frequencies at the transfer station. A station at Norumbega Junction would be able to reach rapid transit headways with a combination of 4 short-turn trains per hour plus 2 Framingham all-stops locals:

ServiceTime
Framingham Local:00
Norumbega Local:10
Norumbega Local:20
Framingham Local:30
Norumbega Local:40
Norumbega Local:50

And that's before adding any Worcester trains into the mix, which could swap out for two of the Norumbega Locals (depending on how you want to approach providing service to the Newtons), or could be added on top of the services listed above to increase frequencies further.

That all goes out the window if you do a spur to Riverside. At best, you'd see 15-minute headways at Riverside, which isn't turn-up-and-go, and will compete unproductively with the more frequent Green Line service (and likely will have significant walking distance between Green and Indigo platforms.) Keeping everything on the mainline maximizes the usefulness of a frequency layer cake.
 
But neither of them would be possible P&R spots RIGHT OFF THE PIKE

That's what Riverside itself is for, and I think the flat junction would be fine. Rail Vision recommended it. The fever dream, btw, is the idea that Weston will permit TOD or infill.

This is basically exactly what I proposed a few months ago as "Norumbega Junction" (larger discussion here).

View attachment 28406

(The diagram is a little hard to read, but the mainline has two platforms with a third passing track in between. I'm not married to that layout.)



I'm not an expert in this, but I think differences in junction design between LRT and mainline make this apples to oranges. From what I've seen, most mainline junctions use "ladders", where trains move from track to track through a series of crossovers, while rapid transit junctions have "direct" crossovers, where the train passes through the crossed track, but doesn't actually occupy it. Crude diagram:

View attachment 28408

This means that the diverging crossing mainline train blocks both tracks for a longer period, while the LRT setup reduces conflict time.

But setting aside the flat junction problem, I prefer a transfer station on the Worcester Line directly rather than at Riverside because it allows you to maximize frequencies at the transfer station. A station at Norumbega Junction would be able to reach rapid transit headways with a combination of 4 short-turn trains per hour plus 2 Framingham all-stops locals:

ServiceTime
Framingham Local:00
Norumbega Local:10
Norumbega Local:20
Framingham Local:30
Norumbega Local:40
Norumbega Local:50

And that's before adding any Worcester trains into the mix, which could swap out for two of the Norumbega Locals (depending on how you want to approach providing service to the Newtons), or could be added on top of the services listed above to increase frequencies further.

That all goes out the window if you do a spur to Riverside. At best, you'd see 15-minute headways at Riverside, which isn't turn-up-and-go, and will compete unproductively with the more frequent Green Line service (and likely will have significant walking distance between Green and Indigo platforms.) Keeping everything on the mainline maximizes the usefulness of a frequency layer cake.

With all you're proposing I guess it's kind of built in to fix this, but the grade on the Recreation Road straightaway precludes a station there, IIRC. Just like the stretch next to the casino in Everett.
 
Last edited:
With all you're proposing I guess it's kind of built in to fix this, but the slope on the Recreation Road straightaway precludes a station there, IIRC. Just like the stretch next to the casino in Everett.
Womp womp. I'll need to look at that.

As for Weston, you're not wrong!

Like I said in the other thread (I think it was there), I think there's an argument in favor of 15-min headways all the way to Framingham. That could potentially sidestep the entire question of how to turn trains at 128 -- or enable low-frequency short-turns that turn on an improved non-revenue spur to Riverside with no platform, just to buff up frequencies within 128.
 
Like I said in the other thread (I think it was there), I think there's an argument in favor of 15-min headways all the way to Framingham.

They were doing that in 2019 peak (2 Express, 2 Local trains in the 6 and 7 AM hour inbound)
 
They were doing that in 2019 peak (2 Express, 2 Local trains in the 6 and 7 AM hour inbound)
Yeah though to clarify I think there's probably argument as well for 4 tph service to Wellesley and Natick as well. Which would be 4 tph to all local stops from Framingham inward, plus probably at least one Worcester express thrown into the mix.
 
Like I said in the other thread (I think it was there), I think there's an argument in favor of 15-min headways all the way to Framingham. That could potentially sidestep the entire question of how to turn trains at 128 -- or enable low-frequency short-turns that turn on an improved non-revenue spur to Riverside with no platform, just to buff up frequencies within 128.

Yeah...I don't know if the junction of Pike/128 is all that transit-deprived to begin with. You've got 2 consecutive 128 exits with Green Line park-and-rides. If the Fitchburg Line superstation comes in it'll be 3 out of 4 consecutive exits. If GLX-Needham comes in it'll be 4 out of 6 consecutive exits. Then :15 Urban Rail likely coming to Dedham Corporate and Westwood further south. I don't think a Regional Rail stop at Riverside...be it at a GL superstation or a different location against the screams of Weston NIMBY's...is going to uncork anything above-and-beyond for highway users.

The thing the Rail Vision was thinking of by including the spur was more for intra-Newton or Newton-Allston transit. Like...if Riverside TOD took off and that became an employment center people inbound in Newton/Allston needed to get to, or if Riverside superstation became a pooling launchpad from Newton/Allston for 128 biz shuttles shooting north to Waltham/Lexington/Burlington and south to Wellesley/Needham. That kind of thing. The means test for Riverside CR would be the strength of intra-Zone trips (or, conversely, lackthereof)...not extra park-and-riders when there's shaping up to be such bountiful options within spitting distance of 90/128.
 
1. You do realize that the Pike is also at that intersection, right? The combination of a quicker train ride and easier access from the Pike should shave 8-10 mins off the commute.
2. The FRA allows a 1% grade on platforms. That translates to 8ft. The area along Recreation Rd does not vary by more than 8ft, at least not according to USGS.
3. Neither does the area just north of Encore, again, according to the USGS.
 
1. You do realize that the Pike is also at that intersection, right? The combination of a quicker train ride and easier access from the Pike should shave 8-10 mins off the commute.
2. The FRA allows a 1% grade on platforms. That translates to 8ft. The area along Recreation Rd does not vary by more than 8ft, at least not according to USGS.
3. Neither does the area just north of Encore, again, according to the USGS.
Or east, depending on your point of view
 
1. You do realize that the Pike is also at that intersection, right? The combination of a quicker train ride and easier access from the Pike should shave 8-10 mins off the commute.
2. The FRA allows a 1% grade on platforms. That translates to 8ft. The area along Recreation Rd does not vary by more than 8ft, at least not according to USGS.
3. Neither does the area just north of Encore, again, according to the USGS.

I'm curious where you're getting the terrain information (since it's not linked). If it's not railroad-specific, I wonder how well it captures things like the embankments approaching bridges.
 
I'm curious where you're getting the terrain information (since it's not linked). If it's not railroad-specific, I wonder how well it captures things like the embankments approaching bridges.
Put "topo map" or USGS into your search engine. But hey, maybe they don't know what they are doing
 
1. You do realize that the Pike is also at that intersection, right? The combination of a quicker train ride and easier access from the Pike should shave 8-10 mins off the commute.

Wellesley Farms isn't that much further.
 
Wellesley Farms isn't that much further.
But if I live in Sudbury or Northern Natick or a number of other places, I don't want to spend 10 -15 min on town streets. I want to use a ramp that puts me right into a garage.
 
But if I live in Sudbury or Northern Natick or a number of other places, I don't want to spend 10 -15 min on town streets. I want to use a ramp that puts me right into a garage.
The Weston stop only has direct Pike offramps if you're coming from Boston via the Park Rd. exit...and this stop is not meant to capture reverse-commutes from Newton/Boston. From anywhere MetroWest you're getting off to 128N, then MA 30 ramp off the collector/distributor roads, taking a left at the light onto 30, going through the River Rd. set of lights, taking a left at the Park Rd. lights, then arrive at the station. You spend...10-15 minutes on town streets...going that way at peak traffic load. Whereas getting to the existing Riverside stop is: bear right onto 128S, stay in right lane at the merge, get immediately off at the Grove St. loop ramp, arrive at the Riverside lot...no lights. It's a third of a mile shorter physical drive with no traffic lights and significantly fewer turn directions to follow.

The Weston site is the harder one to get to from MetroWest and the current station the easier one...by considerable margin. There may be other factors (TOD, Westonites-willing) to consider here, but ease of Pike/MetroWest driving isn't one of them and is pretty well-settled business with the current stop.
 
Last edited:
The Weston stop only has direct Pike offramps if you're coming from Boston via the Park Rd. exit...and this stop is not meant to capture reverse-commutes from Newton/Boston. From anywhere MetroWest you're getting off to 128N, then MA 30 ramp off the collector/distributor roads, taking a left at the light onto 30, going through the River Rd. set of lights, taking a left at the Park Rd. lights, then arrive at the station. You spend...10-15 minutes on town streets...going that way at peak traffic load. Whereas getting to the existing Riverside stop is: bear right onto 128S, stay in right lane at the merge, get immediately off at the Grove St. loop ramp, arrive at the Riverside lot...no lights. It's a third of a mile shorter physical drive with no traffic lights and significantly fewer turn directions to follow.

The Weston site is the harder one to get to from MetroWest and the current station the easier one...by considerable margin. There may be other factors (TOD, Westonites-willing) to consider here, but ease of Pike/MetroWest driving isn't one of them and is pretty well-settled business with the current stop.
Except there are plans to rebuild the whole area
 
Except there are plans to rebuild the whole area

I know nothing about this area, do the plans have provisions to solve the ramp/traffic issues F-Line identified, or is that something that's not in the plans (regardless if we wished it might be)? Because it's only a valid rebuttal if it's an actual solution; if they're not going to wind up doing the rebuilding in a way that solves the problem, it will remain a problem for trying to access that suggested station site. (Again, I'm asking because I legitimately don't know what the case is here and you seem more knowledgeable about it than me.)
 
At this point, nothing but vague notions that bridges are nearing the end of life. When Allston first came on the radar screen, there was talk about this intersection being next.
 
I know nothing about this area, do the plans have provisions to solve the ramp/traffic issues F-Line identified, or is that something that's not in the plans (regardless if we wished it might be)? Because it's only a valid rebuttal if it's an actual solution; if they're not going to wind up doing the rebuilding in a way that solves the problem, it will remain a problem for trying to access that suggested station site. (Again, I'm asking because I legitimately don't know what the case is here and you seem more knowledgeable about it than me.)

A developer is intending to convert the office complex just north of Rec Road into lab space so this whole discussion is moot anyway.
 

Back
Top