Regional Rail (RUR) & North-South Rail Link (NSRL)

[HenryAlan]

Re: North-South Rail Link

I would think under the proposed scheme, all Northside trains could theoretically go through, since there would be 1:1 matching with lines on the Southside portal. Although maybe it's more complicated than that.

 

[F-Line to Dudley]

Re: North-South Rail Link

So which northside lines will use the link under this proposal? Clearly half the southside lines will continue to terminate all trains at SS.

Don't know, but the 4-on-2 mismatch of mainlines means a whole lot of destinations are going to get stiffed with sub-RER level schedules in the tunnel nullifying a lot of the cross-platform transfer utility. And it is doubleplusbad now that NS Under has zero connection to NS Upper, because surface backfill is the only way to implement RER on the lines that don't pair well or often in the tunnel...surface backfill to upstairs/downstairs transfers. Oops!...can't do that without a subway double-transfer! This scheme ends up taking a steaming crap on northside mobility, and is basically self-crippled against receiving fed funds because the NH/ME interstate schedules needing jobs access to both halves of 128 are the first victims. It'll then lose lots of political support in Worcester and Middlesex Counties because Fitchburg and Haverhill are the next most-likely victims.

Great big ugly self-fulfilling prophecy. At least with the option to defer the Southampton portals in the CA/T plan it was with the understanding that some northside lines would take longer to electrify than others, and thus they could buy time to pay for the last wire-ups + the Fairmount/OC portals on the installment plan before they had to see it to completion for mainline-on-mainline parity. Here you never have that option, so there's conflicts galore.


But...wait!...it gets worse:

Remember how constrained the Southwest Corridor tunnel is on the NEC, and how accommodating T growth within projected 2040 Amtrak service levels means they have to vacate 2 branchlines (Needham and Franklin) off the Corridor. The Needham solution is the same as it was before: convert to rapid transit. But what about Franklin now if Fairmount can't reach the tunnel? It's no longer open-shut to move it permanently over. Tunnel slots will be hellbound to the NEC, and Foxboro--which was never intended to use the NEC at all--must start bogarting NEC slots for any tunnel access. So you haven't reduced the branchline load at all, just traded one problem for another. It means all 4 NEC Purple Line schedules are going to have to sacrifice frequencies for run-thru representation, and all 4 will have quite less than RER-level representation in the Link. Who loses now when Providence is a hot destination and the Link is one of the few things out there that could eventually goose South Coast demand to actually paying back some of the SCR investment? And who in Norfolk County loses now when so many of their slots have to be backfilled on the surface because their few token run-thrus are infrequent and sardine-packed?

I hope the critics who see SSX as somehow competing directly against NSRL get a load of these self-inflicted wounds, because if you have to backfill that much Franklin Line RER frequencies to the surface from it getting peanuts for tunnel slots you better have all those Dot Ave. platforms built.


As I said the other day, this makes a mockery of the RER operating practices that we know to be the only prerequisite that'll actually justify the cost. Break transfer connectivity for too many people and run headfirst into a capacity brick wall and you end up with something too far less than the sum of its parts. This $9B shit sundae should get graded an automatic F for being so thoroughly anti-RER in the choices its makes.

 

[F-Line to Dudley]

Re: North-South Rail Link

I would think under the proposed scheme, all Northside trains could theoretically go through, since there would be 1:1 matching with lines on the Southside portal. Although maybe it's more complicated than that.

They can't. It's a capacity mismatch with Fairmount and Old Colony forever omitted. See previous post on how the SW Corridor capacity constraint bites them in the ass all over again where in a Fairmount/OC-connected universe it would work just fine.

The pairings end up so constrained that if we are running RER frequencies, 2 northside lines (probably Firchburg and Haverhill) will end up turning on the surface most of the time, some northside "Indigo" schedules short-turning at 128 will be mostly surface-bound, and you'll have to expand NS surface with extra platforms and build Drawbridge #3 all the same to possibly absorb all the surface backfill. And none of those surface users will ever ever be able to make a direct transfer to the other side of 128 because of the separated stations, meaning deep political skepticism everywhere north of Boston on the price tag for this.

And if there's no intention of doing RER...you still need the current-sized NS, will have the same knives-out political opposition to the project, AND there'll be no change in the complaints and creeping economic stagnation over crap frequencies.

 

[F-Line to Dudley]

Re: North-South Rail Link

Here's the actual Preferred Alignment report: https://www.mass.gov/files/documents/2018/12/11/NSRL_FinalReport_20181210_Ch8_0.pdf

You'll notice that most of the 20 pages are dry technical evals of TBM diameters applicable to any of the alignments...but everything about the actual alignment choice is relegated to 2-1/2 flimsy pages, with flimsy explanation devoted to why the scoring weights that delivered the win for Congress were construed the way they were.

I can't even begin to describe how un-serious this is. $9B for a 2-track alignment with just the NEC/Worcester south portal. If they desire to add the optional +2 tracks and the Fairmount/OC portal, they must construct the CA/T alignment wholly separately. You heard that right...to get the full capacity they have to build the same project TWICE. Not just on the other side of a dividing wall like a 4-track C/AT, but on wholly separate alignment to different destinations because the +2 on the C/AT alignment would actually hit the real North Station. All of that demographic blah blah blah about jobs being closer to State-Haymarket station (nevermind the fact that CA/T-alignment NS Under would've hit Haymarket all the same), and only some people would get access. And you'd need a paper schedule to tell which from which.

And yet, their main beef with the C/AT alignment is that the stations had to be pre-provisioned for 4 feeder tracks of tunnel capacity even if they started with only 2 and added 2 later. That one-time future-proof charge was somehow a disqualifying problem...but building the whole fucking thing twice with whole fucking separate stations was somehow not. The hostility to RER service levels just oozes from all this pretzel logic.

They also 'think' that Congress has less flood risk...but then didn't even score it to demonstrate and blanketed it with an "all locations are [50-year] problematic" statement. 'Think' Congress is better, but also think C/AT is fine for the +2 track expansion. Really, guys...there's reams of active studies going on all around re: Boston flood resiliency and you took a big ol' punt on that???


As preordained conclusions go, this is one very undercooked can of Alpo.

 

[fattony]

Re: North-South Rail Link

With 17 trains per hour per direction going into the tunnel, what is the continued purpose of north station at the surface? It doesn’t handle anywhere near that kind of traffic now does it? The red line doesn’t handle that. What precludes just shuttering north station entirely? (Please phrase your answer in the form the English language without all the jargon. We know you know all about railroads. You aren’t communicating to us if you don’t make your points in terms we understand)

 

[jass]

Re: North-South Rail Link

Theres no reason to keep North Station as a train depot, but it could be used for other stuff.

See also: Redding Terminal in Philadelphia.

 

[CSTH]

Re: North-South Rail Link

With 17 trains per hour per direction going into the tunnel, what is the continued purpose of north station at the surface? It doesn’t handle anywhere near that kind of traffic now does it? The red line doesn’t handle that. What precludes just shuttering north station entirely? (Please phrase your answer in the form the English language without all the jargon. We know you know all about railroads. You aren’t communicating to us if you don’t make your points in terms we understand)

let me take a crack at this:

The purpose of NS at the surface in a world where 17 trains per hour go through the tunnel would be....to allow the northside system to handle more than 17 trains per hour.

Consider that there are 4 branches on the north side - (or 5 if you count newbury/rock as 2). 17 tph works out to about 4 per hour per branch - or one train every 15 minutes.

That's about 1/5 of what the red line does.

There are good reasons to believe that will be demand to support capacity in excess of one train every 15 minutes for large sections of each of those 4 branches.

Does that help?

 

[F-Line to Dudley]

Re: North-South Rail Link

let me take a crack at this:

The purpose of NS at the surface in a world where 17 trains per hour go through the tunnel would be....to allow the northside system to handle more than 17 trains per hour.

Consider that there are 4 branches on the north side - (or 5 if you count newbury/rock as 2). 17 tph works out to about 4 per hour per branch - or one train every 15 minutes.

That's about 1/5 of what the red line does.

There are good reasons to believe that will be demand to support capacity in excess of one train every 15 minutes for large sections of each of those 4 branches.

Does that help?

Bingo. The NSRL is a giant white elephant if the Purple Line hasn't implemented Regional Rail-level frequencies of significantly more than twice today's overall levels, per the TransitMatters recs. This 'preferred' NSRL plan assumes sucky status quo frequencies forever to keep the price tag from ever being worth it.

• The 4-on-2 mismatch of northside vs. southside mainlines means a jarring inequity in the line pairings that can regularly match up in the tunnel.

• This gets worse when you've increased the number of branchline schedules that have to run smack into the SW Corridor's capacity constraints on the NEC. We're supposed to be relocating branches like Franklin off the NEC so Amtrak and Providence/Stoughton can breathe well into 2040 and into the Link era, not add to the problem by forcing Foxboro and under-duress northside schedules to thread through there.

• Because of these mismatches and constrictions, some very large-ridership lines will have skewed majorities of schedules turning on the surface forever because the pairings can't be distributed equitably through the constrictions and priority must be given to the least-brittle schedules.
  • In practical sense this means less oft-delayed Lowell + Eastern Route slots are going to dwarf Fitchburg + Haverhill slots by an enormous margin, which is going to be extremely problematic for political support in those northside Legislative and Congressional districts.
  • South it means Franklin/Foxboro get boned because of the SW Corridor's inability to juggle early-splitting branchlines. These very high-ridership trains will be limited to mostly surface turns via the Fairmount Line, with inadequate breadcrumbs thrown for tunnel slots.

• For the northside, the 'losers' on tunnel pairings will almost never get a chance to direct-transfer to jobs south of the city because their terminal will be sheared off from State-Haymarket on all schedules except a token handful of sardine cans.
  • Direct blunted economic impact to whichever of the Fitchburg, Haverhill, Lowell, North Shore, and/or Norfolk County corridors get the short end of the stick. And shredded political support.
  • Interstate trips won't fit, so no Concord-Westwood, Downeaster-South Station, and probably only the barest token representation of Portland NE Regionals. Will be tough to solicit fed funding for this having New England interstate coattails if NH and ME no longer have quantifiable economic upside.
  • 128-to-128 "Indigo" schedules set to subway fare largely can't run through the tunnel at all, because Riverside is the only such proposed route that can interline. This is a brutal concession that shreds a lot of intra-128 political support.

• Makes a mockery of RER operating principles.
  • The skewing of schedules means what trace tunnel slots do get apportioned to the 'losers' will be very rush-hour oriented, overcrowded, and inefficient on dwell times.
  • The need to give some 'breadcrumbs' to the 'losers' means that even the 'winners' like Providence or Lowell will suffer from lower tunnel frequencies than their true demand, particularly at peak.
  • RER practices would normally keep dwells minimized by running regularly-spaced high frequencies using easy-boarding single-level, three-door EMU's so higher-demand trains don't need to be overcrowded.
  • With overly sparse representation on some 'loser' schedules and less-than optimal peak density on the 'winner' schedules, there's no choice but to run very irregular schedules (i.e. don't toss that paper schedule) with sardine-can bi-levels at a steep dwell penalty.
  • Run at a dwell penalty because crowd-swallowing is prioritized over schedule parity, and tunnel capacity is reduced by the much-increased loading times. At only 2 tracks, it is CRITICAL that they do everything in their power to speed platform dwells to max efficiency. But that's functionally impossible when certain destinations have to suffice on overcrowded breadcrumbs and others have to donate breadcrumbs they can't afford to lose from their own crowd control.

• Bullshittery at its smelliest. . .
  • They claim the only fix for the broken capacity of the Congress alignment is building the same project AGAIN later on on the CA/T alignment, for sake of including the Fairmount & OC portals for mainline parity.
  • In the state's pretzel logic, building it twice on 2 alignments is somehow 'preferred' to building it 2 x 2 tracks on the installment plan on only 1 alignment in the CA/T tunnel.
  • In the state's pretzel logic, building SS and NS on the CA/T alignment is 'non-preferred' because they'd have to be provisioned for 4 tracks even if there's initially only 2, and that's too expensive. But building SS Under + State-Haymarket, then later a wholly separate SS Under + NS Under...that's 'preferred', because reasons.
  • The head-exploding illogic of those build recs means there's no intention to ever go back and balance the pairings, fix the line-by-line inequities, or perma-fix the capacity constraints that erode RER operating practices.
  • Ergo, they're sandbagging RER ops right up-front to ensure they can't ever be implemented in the Link, tanking the Link's entire value proposition and political coalition.

They're also throwing chum in the water at the crowd who listened to now-absentee Seth Moulton bloviate last year about how surface terminals are icky-poo obsolete by pitching the plan that cripples NS surface from being able to transfer elsewhere on the Purple Line. This further aids the sandbagging of RER service levels, because if you want to close NS surface you are explicitly calling for sucky status quo service levels forever. It's impossible to double systemwide frequencies without surface slots, impossible to equitably distribute frequencies with this crippled Congress build overreliant on the SW Corridor and picking some steep losers on pairings, and impossible to equitably integrate a system of across-the-board increased frequencies with Purple-to-Purple transfers intentionally severed at one of the terminal stations.

So...be careful what you ask for if your own sense of transpo facility feng shui gets you advocating for a closure of North Station. It means you're inadvertently advocating for service levels to suck forever. Closing it with a non-broken NSRL alternative is bad enough because it caps the growth potential or RER service levels much too low for true midcentury demand, but closing it with this disaster of a Link plan means not only are service increases impossible...but service cuts and economic ruination go widespread across the north.

Read between the lines; the FCMB is trying to bury the knife in both this project and in the TransitMatters recs for RER practices in one stealth press release.

 

[fattony]

Re: North-South Rail Link

I'm curious - where is the demand for so many trains? The entire CR system carries 122,000 daily riders today. Probably 1/3 of that is on the north side, or about 42,000. Someone feel free to supply a more accurate number. Can we agree those are pretty much all peak riders today?

If we quadrupled the peak rush hour purple ridership to 168,000 riders over the next 50 years, that would be amazing and it would transform Boston. I'm not entirely sure we could generate that many peak CR riders simply because the towns won't allow development patterns to support it, but that is beyond this discussion. In that scenario we wouldn't even have 1 red line worth of passengers on the north side (280,000 riders on RL daily) and the red line only runs 13 tph (or less in practice) to carry 280,000. 17 tph to carry 168,000 riders seems pretty darn comfortable by comparison.

So you are saying 15 minute headways (which qualifies as rapid transit in my book) on the 4 lines merging into the tunnel isn't enough. I would like something to substantiate that. Are you suggesting the NSRL is going to increase CR ridership by more than 4x IN THE PEAK? How much then?



That is all just talking about the tunnel capacity. You can run more trains that terminate at NS surface and a considerable percentage of riders will be happy to grab those trains as well. The longest wait for a tunnel train (with transfer to any south side line at SS) is 15 minutes. Not too shabby, IMO.

 

[CSTH]

Re: North-South Rail Link

Are you suggesting the NSRL is going to increase CR ridership by more than 4x IN THE PEAK? How much then?

Well - a big part of what changes is that we're no longer talking about commuter rail ridership, because we're no longer talking about commuter rail service.

The scenario F-Line is describing is essentially several legs of rapid transit extension to 128 (and beyond). The model is:

- Electric traction (faster and smoother acceleration, for faster overall average speeds and a more comfortable ride, especially if standing).
- Level boarding
- Frequent service, so you can just show up at most times of day instead of consulting a schedule
- strong connectivity to mbta subway lines


If that sounds like the red, orange and blue lines, it should. But in this scenario it also describes rail service at places like chelsea, porter sq, swampscott, salem, waltham...and also at new alewife-style park & rides in Woburn, Reading, and Beverly (insha'allah). And its giving you service directly to financial district & backbay & most of the seaport, among others.

Now: also assume that Boston continues growing at a steady pace, but the highways don't get expanded any more (i'll give you another lane on the northern segment of 128 and maybe 93 up near NH...but that just puts more pressure on the inner spokes anyway).

I think its a slam dunk that a lot of people are going to use that service, even if they don't currently take the commuter rail.

Again - ' NSRL increasing commuter rail ridership' is entirely the wrong way to look at it. Its about replacing commuter rail with new rapid transit lines on the old rail ROWs, and the NSRL tunnel is just one part of making that happen.

Can't be emphasized enough. NSRL is not the project. Regional Rapid Transit is the project, and NSRL is a key element of it.

 

[bigpicture7]

Re: North-South Rail Link

Well - a big part of what changes is that we're no longer talking about commuter rail ridership, because we're no longer talking about commuter rail service.

The scenario F-Line is describing is essentially several legs of rapid transit extension to 128 (and beyond). The model is:

- Electric traction (faster and smoother acceleration, for faster overall average speeds and a more comfortable ride, especially if standing).
- Level boarding
- Frequent service, so you can just show up at most times of day instead of consulting a schedule
- strong connectivity to mbta subway lines


If that sounds like the red, orange and blue lines, it should. But in this scenario it also describes rail service at places like chelsea, porter sq, swampscott, salem, waltham...and also at new alewife-style park & rides in Woburn, Reading, and Beverly (insha'allah). And its giving you service directly to financial district & backbay & most of the seaport, among others.

Now: also assume that Boston continues growing at a steady pace, but the highways don't get expanded any more (i'll give you another line on the northern segment of 128 and maybe 93 up near NH...but that just puts more pressure on the inner spokes anyway).

I think its a slam dunk that a lot of people are going to use that service, even if they don't currently take the commuter rail.

Again - ' NSRL increasing commuter rail ridership' is entirely the wrong way to look at it. Its about replacing commuter rail with new rapid transit lines on the old rail ROWs, and the NSRL tunnel is just one part of making that happen.

Can't be emphasized enough. NSRL is not the project. Regional Rapid Transit is the project, and NSRL is a key element of it.

100%. Everyone I know who lives on a commuter rail line, and works in Boston, but doesn't take the commuter rail has the same excuse: trains don't come frequently enough / take too long, thus, the CR doesn't offer the flexibility they need to integrate their work into their lives. Imagine: you usually work until __pm, but if you're 10 mins late getting out of the office one day, you miss your usual CR train home, then have to wait 30-45min for the next one. This alone dissuades workers from taking the CR...it impacts dinner with their families, picking up/seeing their kids, evening time etc.
People crave flexibility of frequent service, and are willing to take an inferior commuting option so long as it preserves that flexibility/autonomy.

Regional Rail would completely change this, and get more people off the roads.

 

[fattony]

Re: North-South Rail Link

The missing piece in your grand plan is that this system serves commuter rail stations in low density suburbs, not rapid transit stations in urban areas (I'll grant you a small handful like Porter and Chelsea). How are you going to get 10x more passengers in and out of those suburban stations? You can't build enough parking or enough walkable homes to make that work. Bus feeders? We have anemic buses feeding our current rapid transit lines and are struggling to make it work in real dense urban areas. How are you going to replicate that in even less dense areas that are actively hostile to any mode but automobile?

I'm a little worried that you guys might be putting the cart way in front of the horse. You have this plan for extremely high-level rapid transit service to places that don't have and WON'T have that many riders in the next century. The ridership I sketched out above at least passes the smell test and isn't exactly a drop in the bucket. It would completely transform Greater Boston. You are talking about a whole other leap BEYOND that. You are talking about giving the same service level to Ayer as to Cambridge. What sense does that make?

 

[DominusNovus]

Re: North-South Rail Link

The missing piece in your grand plan is that this system serves commuter rail stations in low density suburbs, not rapid transit stations in urban areas (I'll grant you a small handful like Porter and Chelsea). How are you going to get 10x more passengers in and out of those suburban stations? You can't build enough parking or enough walkable homes to make that work. Bus feeders? We have anemic buses feeding our current rapid transit lines and are struggling to make it work in real dense urban areas. How are you going to replicate that in even less dense areas that are actively hostile to any mode but automobile?

I'm a little worried that you guys might be putting the cart way in front of the horse. You have this plan for extremely high-level rapid transit service to places that don't have and WON'T have that many riders in the next century. The ridership I sketched out above at least passes the smell test and isn't exactly a drop in the bucket. It would completely transform Greater Boston. You are talking about a whole other leap BEYOND that. You are talking about giving the same service level to Ayer as to Cambridge. What sense does that make?

Doesn’t branching take care of this?

 

[CSTH]

Re: North-South Rail Link

I'm not entirely sure we could generate that many peak CR riders simply because the towns won't allow development patterns to support it, but that is beyond this discussion.

...The missing piece in your grand plan is that this system serves commuter rail stations in low density suburbs, not rapid transit stations in urban areas (I'll grant you a small handful like Porter and Chelsea). How are you going to get 10x more passengers in and out of those suburban stations? You can't build enough parking or enough walkable homes to make that work. Bus feeders? We have anemic buses feeding our current rapid transit lines and are struggling to make it work in real dense urban areas. How are you going to replicate that in even less dense areas that are actively hostile to any mode but automobile?

One additional point I feel compelled to make:

It may be true that places like Belmont, Winchester and Concord aren't likely to go for dense multi-story apartments and condos in walking distance to regional rapid transit stations.

However...

There's a whole constellation of honest-to-god cities on the Eastern Mass rail network here that already have very dense and highly walkable develop patterns, and that can nonetheless also support even denser rapid-transit-oriented development.

Just on the Northside, we're talking about:

- Chelsea
- Salem
- Beverly
- Lowell
- Lawrence
- Haverhill
- Lynn
- Waltham
- Swampscott

That's like 500,000+ people. (Yes, I know that not all 500,000 are going to be in walking distance of the train.) That's a lot of people.

And all of those places will (and already are) enthusiastically embracing dense, multi-story downtown apartments & condos.

 

[F-Line to Dudley]

Re: North-South Rail Link

I'm curious - where is the demand for so many trains? The entire CR system carries 122,000 daily riders today. Probably 1/3 of that is on the north side, or about 42,000. Someone feel free to supply a more accurate number. Can we agree those are pretty much all peak riders today?

If we quadrupled the peak rush hour purple ridership to 168,000 riders over the next 50 years, that would be amazing and it would transform Boston. I'm not entirely sure we could generate that many peak CR riders simply because the towns won't allow development patterns to support it, but that is beyond this discussion. In that scenario we wouldn't even have 1 red line worth of passengers on the north side (280,000 riders on RL daily) and the red line only runs 13 tph (or less in practice) to carry 280,000. 17 tph to carry 168,000 riders seems pretty darn comfortable by comparison.

So you are saying 15 minute headways (which qualifies as rapid transit in my book) on the 4 lines merging into the tunnel isn't enough. I would like something to substantiate that. Are you suggesting the NSRL is going to increase CR ridership by more than 4x IN THE PEAK? How much then?



That is all just talking about the tunnel capacity. You can run more trains that terminate at NS surface and a considerable percentage of riders will be happy to grab those trains as well. The longest wait for a tunnel train (with transfer to any south side line at SS) is 15 minutes. Not too shabby, IMO.

See the other responses as those accurately describe the RER element. RE: tunnel capacity, you are NOT getting 15 min. headways per line. That calculation was Trains Per Hour. 4 TPH per line isn't a 15-min. headway because those 4 slots are divvied up EACH direction. 4 TPH means a maximum 30-min. headway per mainline if all is divided equally. Right then and there you can't implement "Indigo" service to 128 on subway fare through the tunnel because the headways WON'T be good enough for 15-20 mins. each direction.


Also...if things aren't divided equally you get more service in one direction, less in the other...which is antithetical to RER practice because it bottles up equipment rotations. And apportioned by winners/losers it means Providence & Lowell might have decent slotting while Fitchburg and Forge Park live in a desert of hour-plus headways that have to be backfilled on the surface (where NS Purple-to-Purple transfers are impossible.


It's horribly skewed and impedes the only service levels--RER--that'll justify the cost.

 

[bigpicture7]

Re: North-South Rail Link

The missing piece in your grand plan is that this system serves commuter rail stations in low density suburbs, not rapid transit stations in urban areas (I'll grant you a small handful like Porter and Chelsea). How are you going to get 10x more passengers in and out of those suburban stations? You can't build enough parking or enough walkable homes to make that work. Bus feeders? We have anemic buses feeding our current rapid transit lines and are struggling to make it work in real dense urban areas. How are you going to replicate that in even less dense areas that are actively hostile to any mode but automobile?

I'm a little worried that you guys might be putting the cart way in front of the horse. You have this plan for extremely high-level rapid transit service to places that don't have and WON'T have that many riders in the next century. The ridership I sketched out above at least passes the smell test and isn't exactly a drop in the bucket. It would completely transform Greater Boston. You are talking about a whole other leap BEYOND that. You are talking about giving the same service level to Ayer as to Cambridge. What sense does that make?

fattony, it's a coupled system; a RR concept would induce all kinds of demand that we're not presently seeing from medium-density nodes. I used to live in Andover, which has tons of homes walking distance from the CR stop, yet my neighbors would have all kinds of excuses why they didn't take the train.

I agree with you that demand might not be there at every stop, but there's a lot more than is being tapped right now. Neither of us could answer this without some complex systems modeling.

 

[fattony]

Re: North-South Rail Link

See the other responses as those accurately describe the RER element. RE: tunnel capacity, you are NOT getting 15 min. headways per line. That calculation was Trains Per Hour. 4 TPH per line isn't a 15-min. headway because those 4 slots are divvied up EACH direction. 4 TPH means a maximum 30-min. headway per mainline if all is divided equally. Right then and there you can't implement "Indigo" service to 128 on subway fare through the tunnel because the headways WON'T be good enough for 15-20 mins. each direction.

From the report:

All Two-Track alignments are assumed to have capacity for up to 24 trains per hour in each direction. In this analysis, it is assumed that two to three of those trains are Amtrak Regional services (other Amtrak services are assumed to terminate at South Station). That leaves 21-22 train “slots” per hour for MBTA services, however upstream constraints limit the actual throughput to 17 trains per hour, per direction from both the northern lines and the southern lines merging at Back Bay Station.

It's horribly skewed and impedes the only service levels--RER--that'll justify the cost.

Would you mind defining what you keep yammering about "RER service levels"? If you mean a specific headway, just say the number.

 

[fattony]

Re: North-South Rail Link

fattony, it's a coupled system; a RR concept would induce all kinds of demand that we're not presently seeing from medium-density nodes. I used to live in Andover, which has tons of homes walking distance from the CR stop, yet my neighbors would have all kinds of excuses why they didn't take the train.

I agree with you that demand might not be there at every stop, but there's a lot more than is being tapped right now. Neither of us could answer this without some complex systems modeling.

I understand and I agree. I'm suggesting that a 2-track concept that misses North Station isn't exactly a useless piece of crap as F-Line has expressed so verbosely.

• You get 15 minute headways from every station on the north side through the tunnel
  
• You get maybe 7.5 minute headway from every station on the north side to North Station
  
• You get 12-ish minute headways from the southern/western tunnel lines to the tunnel (not sure how all the splits would go)
  
• OC and Fairmount get stuck with transfers at SS, but they get all north side lines there (not to mention red and silver)

That's not exactly a crap system. Adding more terminal terminating trains on each line can give service level approaching RL/OL level. Not every train will hit the tunnel, but you will have rapid transit headway to tunnel as well. All purple connections are possible at South Station and every subway line touches the tunnel.

Believe me, my preferred alternative is the 4 track CAT route. I'm just trying to figure out what is the potential with the recommended alternative.

 

[bigpicture7]

Re: Regional Rapid Transit Plan (including the North-South Rail Link)

^ thanks for clarifying / offering this breakdown of what you meant.

 

[Shepard]

Re: North-South Rail Link

One additional point I feel compelled to make:

It may be true that places like Belmont, Winchester and Concord aren't likely to go for dense multi-story apartments and condos in walking distance to regional rapid transit stations.

However...

There's a whole constellation of honest-to-god cities on the Eastern Mass rail network here that already have very dense and highly walkable develop patterns, and that can nonetheless also support even denser rapid-transit-oriented development.

Just on the Northside, we're talking about:

- Chelsea
- Salem
- Beverly
- Lowell
- Lawrence
- Haverhill
- Lynn
- Waltham
- Swampscott

That's like 500,000+ people. (Yes, I know that not all 500,000 are going to be in walking distance of the train.) That's a lot of people.

And all of those places will (and already are) enthusiastically embracing dense, multi-story downtown apartments & condos.

YES. And add to that the populated and walkable areas on the south side - including the entirety of the Fairnount line, Needham line, and Worcester Line out to Auburndale... along with Brockton, Stoughton, Canton, Legacy Place, University Ave, Norwood, Walpole, Hyde Park... that's huge.