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Old 12-18-2018, 10:32 PM   #3421
Wash
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Re: Crazy Transit Pitches

I was talking with TransitMatter's regional rail director earlier today, and asked him how he'd solve the Braintree chokepoint on the old colony lines.

He suggested ripping out red entirely and converting the whole thing to a two-plus 1 express track regional rail corridor. This seems like a bad solution at first, but with the new room we can talk seriously about SCR via Old Colony, and if we run that plus the other three lines we're talking ten minute headways.

Yes it's a very radical change, but could it work?
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Old 12-19-2018, 12:31 AM   #3422
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Re: Crazy Transit Pitches

Well, I could see the Red Line as three tracks instead of the current four, with the middle track reversible, AM northbound and PM southbound. That would free up space for a second track for the Old Colony line.
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Old 12-19-2018, 06:58 AM   #3423
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Re: Crazy Transit Pitches

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Originally Posted by Wash View Post
I was talking with TransitMatter's regional rail director earlier today, and asked him how he'd solve the Braintree chokepoint on the old colony lines.

He suggested ripping out red entirely and converting the whole thing to a two-plus 1 express track regional rail corridor. This seems like a bad solution at first, but with the new room we can talk seriously about SCR via Old Colony, and if we run that plus the other three lines we're talking ten minute headways.

Yes it's a very radical change, but could it work?
No, it would not work and it's a horrendously bad idea. It would worsen headways to Dorchester and Quincy, because they can't be dispatched as tightly out of an open-network terminal like South Station with interdependencies on every other train in/out of SS. RER is very, very good frequencies but it is NOT the same as thing as a closed-system heavy-rail subway that only has to dispatch itself between Alewife and Columbia Jct. to meet an aggressive frequency target. And those Red frequencies to the branches are set to get a lot better with the new cars, signal renewal, and dwell-taming practices anyway so the gap is set to widen in 3 years.

I can't believe a TM flak would be whispering about robbing someone's frequencies to either pay for someone else's or uphold one's own integrity-of-concept. Talk about loose lips sink ships...that is lethal for coalition-building. This better not become a habit of them.

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

SCR via the Old Colony is utter swill anyway with worse travel times, worse frequencies, and transit loss to boot (Cape rail, Middleboro station) compared to the only half-broken Stoughton Alternative. It'll never work as useful transit, and they've got threatened lawsuits from (so far) Towns of Middleboro and Taunton to stop it dead if it proceeds any further than the enriching-consultants PowerPoints stage it's in now. I firmly believe that because of the threatened lawsuits it's still Stoughton-or-bust, though they have to challenge the Army Corp's faulty DEIR on the single-track swamp trestle and factor in some serious NEC upgrades if they want to un-break the artificial capacity pinch.

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

There are only 3 OC branches, and flights-of-fancy about SCR aside there's only going to be 3 OC branches. You can run 3 branches of RER on 2 tracks; the Eastern Route is going to do exactly that without need to add tracks if Peabody/128 comes online, so nothing's unprecedented here. And the OC's not going to get bogged down on 2 tracks because the 3 inside-128 stops are all majority exit-only transfers to Red and buses with very low dwell times. Something the TM flak should've been aware of before proposing to go against the grain.

Also, density on the 3 branches has to be factored in. You can run near-"Indigo" 15-20 minute all-day frequencies to Brockton because it's the largest city en route and has a very large bus terminal. But...
  • Middleboro/Buzzards Bay isn't going to fetch crumbs at 15-20 min. levels because those are a semi-rural to rural bedroom communities comprising very spread-out geographic area. This is typical "495-land", more appropriate for 30+ min. turns. Service throttling at Brockton is going to be necessary.
  • Cape Cod is so detached from Greater Boston, with stagnant long-term population growth and transit demand that's so dependent on bridge traffic by time of day that it probably can't justify more than hourly service with maybe a slight peak surge. Probably another service throttle looming at Buzzards Bay before crossing the bridge.
  • The Plymouth Line intermediates likewise lose their quasi-"Indigo" demand south of Weymouth, and go semi-rural south of Whitman (though Abington & Whitman can be boosted on all-day demand if they joined the BAT bus district full-time). Plymouth is a decent-size city...but also physically large and very spread out, and well-detached from Greater Boston. Some service densification with the northern half of the line (possibly with infill stops) is plausible, but it's not nearly as clear-cut as the "Indigo-Brockton" example. Everywhere else is pretty clearly "495-land".
  • Greenbush's only dense region in Weymouth is well within reach of the Quincy Center bus routes, then the density falls way off around Hingham as the rest of the corridor becomes bedroom communities. Not sure there's even a clear dividing line for a mid-line service throttle here, so might as well all be considered a single "495-land" schedule.
Keep in mind that RER practices don't mean a flat hyper-dense headway everywhere to everywhere on a large, sprawling system. Under no circumstances do those practices ask the operator to bleed itself dry running the same homogenous service levels to places of heterogeneous demand. That's an essential difference from the flat headways on rapid transit & branches.

So it's fully OK if the Old Colony only has full-on "Indigo"-branded 15-20 min. headways to Brockton at the single largest multimodal and density demand catchment, but everywhere else gets grouped in with the 30+ minute schedules. It's not at all incongruous if service levels to the exurbs get throttled down, because that's what we'll be doing anyway for 128 vs. 495 terminating runs. And not incongrous if Hyannis has to throttle down some more for being very far-detached from Boston, because that's what we'll be doing for interstate destinations equally far like Wickford Jct. Middleboro/Cape isn't even an outlier at having multiple throttles, because if you consider Haverhill/Reading as 1 line instead of 2 separate ones it'll have the same number of throttles: Reading for "128/Indigo" frequencies, Haverhill for "495-land" frequencies, and Dover, NH for regional intercity frequencies.

What makes it all still RER-practice is that:
  • ...the schedules are clock-facing at the given headway so riders do not have to be shackled to the paper schedule to plan trips.
  • ...the schedules enhance transfer utility with last-mile transit like feeder buses (also prioritizes clock-facing).
  • ...the given headway is run bi-directionally to keep equipment efficiently in rotation instead of bottled up in layover yards as happens with peak-direction schedules.
  • ...if peak augmentation is needed, those slots should try to fit in between the clock-facing headway and disrupt it as little as possible.

It's not as complicated--or compromising--as it sounds. There's a general understanding with RER that "inside-128" is going to have more frequent service than "128-to-495" is going to have more frequent service than "intrastate intercity/across state lines". Simply because that's the broad-based way demand is organized across the system. And that's completely consistent with how the OC would get sliced/diced.
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Old 12-19-2018, 09:29 PM   #3424
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Re: Crazy Transit Pitches

Quote:
Originally Posted by Riverside View Post
Everything else you said makes perfect sense, particularly given the other freight customers that I didn't know about (and thanks for all the detail!). I also like your suggested reconfiguration around JFK/UMass, although I wonder if it might be simpler just to add a flying junction south of Savin Hill, at the location of the old Harrison Square station, where the Ashmont Line turns west, freeing up the Braintree tracks north of there?
  1. Savin Hill is a very low-ridership station (2nd-lowest on all Red), so full-on mainline frequencies are a big waste there.
  2. For taking ailing trains out-of-service from the subway you need crossover options and most conflict-free pick of empty platform berths at a location closest to the portal in order to dump passengers and/or minimize delays reversing to Cabot Yard. Busting JFK down to a single island platform is going to hurt recovery time from a disablement by lots vs. being able to pick which nearby platform berth will be unoccupied the longest.
  3. Not a lot of room between Savin Hall and the Freeport St. bridge to split tracks and flyover. And extremely little lateral room in that stretch. Flying over closer to Clayton St. split is going to punish someone with an ill-advised slow zone by tacking on a graded incline in close proximity to a curve.
Of those #2 is the one that'll burn most frequently.

Quote:
But the quoted above is interesting. I'm not surprised to hear in general, but if memory serves, the CTA in Chicago has a couple of heavy rail grade crossings -- I think on the Ravenswood Line? That was what I had in mind when suggesting the same here. How does Chicago make it work? (Or am I misremembering?)
All of CTA's remaining grade crossings are grandfathered. And they've been trying to get rid of their last remainders for years, but can't come to a consensus on how to do it. While there's no FRA-type body lording over rapid transit, the NTSB would have a field day with that so there'll never be any allowances for new-construction HRT to have public crossings. As late as the 70's they were still considering building the Orange Line to Reading with some of the Western Route's grade crossings retained...but that was several lifetimes ago for the phenomenon of distracted driving/walking.

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Follow-up idea: in a post-Link (with an OC portal) Regional Rail world, what's the argument against converting the Red Line tracks on the Braintree Line to mainline, and running Regional Rail on them, through-running the tunnel downtown out to Porter and Waltham, or some other northside line? You still get the peak-express track, especially for south-of-Middleboro service, but get a lot more capacity overall, plus a faster ride downtown for Quincy and Braintree riders.
Quincy losing their one-seat to Kendall and Harvard is an immediate disqualifier politically, because nothing else can approximate ease of access to Cambridge. Forced transfer to a sardine can at JFK is an unacceptable substitute. Also...RER makes no assumptions that NSRL is getting built, so the wholly-future Porter possibility is irrelevant today. You must implement RER frequencies or the Link has no basis for getting built, and if RER frequencies must pre-date the Link to get it built then so must the fix for OC single-track. You can't sell RER or the track fix on the back of immediate transit loss to Cambridge or you'll get skinned alive in Quincy.

Also, in terms of raw frequencies...not all 3 OC lines qualify for the maximal 15-min. RER headway we call "Indigo" for the 128-turning lines. See my previous post for how hyper-dense service is differentiated from suburban service (or pull up the TransitMatters website where they make the same exact distinction in bullet form) while still following RER operating principles. It's probably only short-turns to Brockton can support all-day demand at 15-min. headways. The other two lines, and service past Brockton slot demographically much firmer in the 30-min. headway category. 30 minutes being pretty damn great in terms of feasible all-day demand from Greenbush, Plymouth, and Middleboro/Buzzards Bay. But it's not going to be Red frequencies, which'll be 3 minute headways to JFK and 6 to Braintree in 2021 after the signal upgrade + car procurement projects are complete.

And even if you could tweak those RER schedules to draw close to par, it's never going to be 6 mins. with a one-seat to Kendall, Harvard, MGH, and all the other big destinations inbound of JFK. That simply can't be done on any Purple Line routing current or future, and that is the be-all/end-all for (substantial!) Quincy/Braintree transit demand.
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Old 12-20-2018, 12:19 PM   #3425
datadyne007
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Re: Crazy Transit Pitches

Hey there, I have a statement from Ethan Finlan, the TM Regional Rail Lead:

Quote:
Originally Posted by Ethan Finlan
"I mentioned that in the context of something that would be worth studying long-term as an option, with a need to carefully study it. I certainly did not intend to suggest that it was an official TransitMatters consideration and am very sorry for the misunderstanding. I appreciate your feedback, F-Line."

Ethan Finlan
Regional Rail Lead
TransitMatters
This was not an official TransitMatters position and should not be construed as such.

Best,
Tim L.
VP of Operations
Communications Director
TransitMatters
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Commuter Rail. Reimagined. Read the report: regionalrail.net
Electrification + High Platforms + Infrastructure + Frequent Service + Free Transfers = #REGIONALRAIL
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Old 12-21-2018, 10:35 PM   #3426
Wash
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Re: Crazy Transit Pitches

Quote:
Originally Posted by datadyne007 View Post
Hey there, I have a statement from Ethan Finlan, the TM Regional Rail Lead:

This was not an official TransitMatters position and should not be construed as such.
Sorry I didn't make this clear in my original post.
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Old 12-22-2018, 01:46 PM   #3427
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Re: Crazy Transit Pitches

Quote:
Originally Posted by F-Line to Dudley View Post
RER makes no assumptions that NSRL is getting built, so the wholly-future Porter possibility is irrelevant today. You must implement RER frequencies or the Link has no basis for getting built, and if RER frequencies must pre-date the Link to get it built then so must the fix for OC single-track. You can't sell RER or the track fix on the back of immediate transit loss to Cambridge or you'll get skinned alive in Quincy.
To be clear, as I said above, this is very explicitly only an idea floated for a post-NSRL world -- something that might be circled back to after many other things. But your point is taken about the sequence of dependencies (OC single-track -> RER -> NSRL), makes sense.

Quote:
Also, in terms of raw frequencies...not all 3 OC lines qualify for the maximal 15-min. RER headway we call "Indigo" for the 128-turning lines. See my previous post for how hyper-dense service is differentiated from suburban service (or pull up the TransitMatters website where they make the same exact distinction in bullet form) while still following RER operating principles. It's probably only short-turns to Brockton can support all-day demand at 15-min. headways. The other two lines, and service past Brockton slot demographically much firmer in the 30-min. headway category. 30 minutes being pretty damn great in terms of feasible all-day demand from Greenbush, Plymouth, and Middleboro/Buzzards Bay.
So here is a question that I don't understand: you've outlined the following mainline rail services north of Quincy Center:
  • 2 tph from Greenbush
  • 2 tph from Kingston/Plymouth
  • 2 tph from Middleboro/Buzzards Bay
  • 2 tph short-turning from Brockton
which adds up to 8 tph, which would, if evenly distributed (and I'm guessing that's the kicker?) translate to headways of 7.5 minutes, which actually is better than the 9-minute peak headways the Red Line currently enjoys.

The way you framed your point here suggests that you think RER frequencies could never come close to Red frequencies, given how few of the OC lines actually qualify for 4 tph service. But this corridor is far enough upstream that it still would be 8 tph for most of it, so I guess my question is, am I missing something here? (Aside from the future Red upgrade to 10 tph.)

Is OC RER likely to be non-clock-facing, with clustering arrivals followed by 25-minute lulls? Is the assumption that the trains will be mostly full by the time they hit Quincy?

Quote:
But it's not going to be Red frequencies, which'll be 3 minute headways to JFK and 6 to Braintree in 2021 after the signal upgrade + car procurement projects are complete.
This was something else I didn't know -- yes, that, particularly combined with one-seats to MGH, Kendall etc., clearly makes a mainline conversion of the Braintree Line a non-starter, that makes sense.
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Old 12-23-2018, 11:20 AM   #3428
F-Line to Dudley
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Re: Crazy Transit Pitches

Quote:
Originally Posted by Riverside View Post
To be clear, as I said above, this is very explicitly only an idea floated for a post-NSRL world -- something that might be circled back to after many other things. But your point is taken about the sequence of dependencies (OC single-track -> RER -> NSRL), makes sense.



So here is a question that I don't understand: you've outlined the following mainline rail services north of Quincy Center:
  • 2 tph from Greenbush
  • 2 tph from Kingston/Plymouth
  • 2 tph from Middleboro/Buzzards Bay
  • 2 tph short-turning from Brockton
which adds up to 8 tph, which would, if evenly distributed (and I'm guessing that's the kicker?) translate to headways of 7.5 minutes, which actually is better than the 9-minute peak headways the Red Line currently enjoys.

The way you framed your point here suggests that you think RER frequencies could never come close to Red frequencies, given how few of the OC lines actually qualify for 4 tph service. But this corridor is far enough upstream that it still would be 8 tph for most of it, so I guess my question is, am I missing something here? (Aside from the future Red upgrade to 10 tph.)

Is OC RER likely to be non-clock-facing, with clustering arrivals followed by 25-minute lulls? Is the assumption that the trains will be mostly full by the time they hit Quincy?



This was something else I didn't know -- yes, that, particularly combined with one-seats to MGH, Kendall etc., clearly makes a mainline conversion of the Braintree Line a non-starter, that makes sense.
It's the combination of these factors that make it a nonstarter:
  • Red is evolving faster than the RER implementation, with those 6-min. headways coming in only 3 years...keeping it at king-of-heap on frequencies.
  • Because East Braintree Jct. splits those Greenbush frequencies off before Braintree Station, Braintree Station sees a 4 TPH decrease.
    • ↑Maths Note↑: Make sure to multiply your TPH's by 2 to reflect track occupancy for bi-directional service. e.g. 30 minute frequencies going both directions = 2 TPH x 2 directions = 4 TPH. In reverse, factor half of the total TPH for figuring the headway, since headway reflects unidirectional frequency to a constant destination/direction. e.g. 4 TPH 2 equal-balanced directions = 2 TPH per direction = 30-min. headway each direction
  • Quincy's commute orientation is to downtown and Cambridge, so the line-in-sand dealbreaker for them is anything that cuts them off from DTX, Park, MGH, Kendall, and Harvard. Since RER cannot make assumptions of an NSRL, transfer at JFK or South Station is acutely harmful to their commute patterns honed over nearly 50 years. And if NSRL ever does happen, transfer at Porter is no substitute for the lost one-seat destinations. That's a multi-municipality lawsuit right there drawing in many Legislators and a couple Congressional districts. A paper study has no ability to graduate to a build rec with all the opposition it'll stir up. In terms of showstoppers, loss of the one-seat job centers is bigger than raw frequencies.
  • Quincy Ctr. is the South Shore's primary bus terminal, and most bus terminals of that size are attached to rapid transit. Shearing it off to another mode with destination (primarily) and frequency compromises risks another neverending quagmire like the "equal or better" debate after Dudley bus terminal lost its rapid transit anchor with the Orange Line relocation in '87. Quincy isn't nearly Dudley's heft in sheer size so the impacts may not dominate to the degree of that 3-decade festering sore in Roxbury, but the controversies and equity debates will rage...and will dovetail with the primary objection to loss of one-seat to key downtown and Cambridge stops. If the one-seat hornet's nest doesn't kill it dead by lonesome, then the Yellow Line coattails feeding to those same destinations are the clincher.
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