MBTA "Transformation" (Green Line, Red Line, & Orange Line Transformation Projects)

jass

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Presentation for B Line stop consolidation project, from last week's virtual meeting. . .


Includes construction schedules and staging details.
The slide on map 9 indicates that the 2 new stations will still be comically close together, to the point that I wonder if a single station between St Paul and Pleasant would have been even better.
 

The EGE

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The nearest entrances are about 800 feet about, but the platforms are midblock. Actual stopping point to stopping point distance is about 1400 feet, perfectly reasonable for surface light rail.
 

F-Line to Dudley

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The slide on map 9 indicates that the 2 new stations will still be comically close together, to the point that I wonder if a single station between St Paul and Pleasant would have been even better.
Not really. St. Paul to Babcock is 1500 ft. crosswalk egress to crosswalk egress, which is right about ideal for LRT spacing. On platform tip to platform tip it's 1250 ft, but there won't be a mid-cycle crosswalk at the east tip of Babcock so the shorter tip-to-tip length doesn't count for accessibility.

Compared to today (crosswalk egress to crosswalk egress). . .
BU Central-BU West: 1925 ft.
BU West-St. Paul: 550 ft.
St. Paul-Pleasant: 750 ft.
Pleasant-Babcock: 750 ft.
Babcock-Packards Corner: 1000 ft.

. . .you net:
BU Central-*new* St. Paul: 1950 ft.
*new* St. Paul-*new* Babcock: 1500 ft.
*new* Babcock-Packards Corner: 1050 ft.

All of the sub-1000 ft. spacers are gone, but the two longest only change by a rounding error on which side of same intersection they're placed. Way cleaner, way more logical. If you went with increments between ⅓ and ½ mile you'd be way off-scale long even by average subway spacing. This is about as spot-on equitable as it gets. Just about the only quibble I'd have is that offset platforms either side of the intersection may have worked better for signal timing vs. doing facing platforms, but that's a small quibble because if Armory St. isn't going to become a thru street facing platforms are basically neutral-performance for 1 of the 2 stops...which doesn't leave any schedule-meaningful bolt-tightening left for the other.


Now...keep in mind BU East/BU Central spacing is still all fucked up at 500 ft. apart and no room on BU East to extend the platforms for Type 10 'supertrains' sans permit to close the Cummington Mall grade crossing. So spacing does need further refinement in ways TBD. If they eventually square-up the BU Bridge intersection clusterfuck into a single-point intersection w/ turn lanes and zap the Carlton St. grade crossing, BU Central would be a shoo-in to move to facing platforms abutting the revamped Bridge intersection at a more equitable 1600 ft. from East and less over-long 1000 ft. from *new* St. Paul. And then closure of the Cummington grade crossing would extend the East platform, while the end result would be -2 traffic signals (Cummington & Carlton) on the Kenmore-BU Bridge stretch vs. today at large schedule savings and elimination of bunching. Remains to be seen when MassHighway will come to its senses on squaring-up that godawful intersection, but all else falls into place after that.
 

jass

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Copley to Hynes is 3,000. Could be 2,500 if they could be bothered to open the existing closed entrance. Clearly, they dont care, so why is it so important to keep the B stops at ~1,000?

Just because its easier to build stops above ground doesnt mean its needed. Ive never heard anyone complain that the subway stops are too far apart. D line stops are all over 2,000 apart, and everyone agrees it's the best line. Additionally, South Street to BC is 2,500, with a closed station in the middle. That was also a well-liked change.
 

whighlander

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Copley to Hynes is 3,000. Could be 2,500 if they could be bothered to open the existing closed entrance. Clearly, they dont care, so why is it so important to keep the B stops at ~1,000?

Just because its easier to build stops above ground doesnt mean its needed. Ive never heard anyone complain that the subway stops are too far apart. D line stops are all over 2,000 apart, and everyone agrees it's the best line. Additionally, South Street to BC is 2,500, with a closed station in the middle. That was also a well-liked change.
Jas -- that's a one dimensional view of spacing
It depends a great deal on what has been or can be built in the "catchment" of the stop -- if you have single family or couple of family homes on the prime street and nearby 2ndary streets then 1/2 mile might be almost too close together
On the other hand -- if your "catchment" includes numerous multifamily, multistory buildings then 1/4 mi be to far apart

You can see this phenomenon on the 77 bus which used to be a streetcar run [there were until recently still some tracks buried in Mass Ave in Arlington]
There are several 5 or 6 story apartment / condo blocks along Mass Ave west of Arlington Center -- at 77 bus stops in that area the bus can fill/empty in a couple of stops

even for a large metropolitan university like BU or Northeaster -- the density of "commuting" varies a considerable amount throughout the campus -- and since that part of the B Line is all about servicing BU -- the stops should be appropriate to the demand
 

jass

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Jas -- that's a one dimensional view of spacing
It depends a great deal on what has been or can be built in the "catchment" of the stop -- if you have single family or couple of family homes on the prime street and nearby 2ndary streets then 1/2 mile might be almost too close together
On the other hand -- if your "catchment" includes numerous multifamily, multistory buildings then 1/4 mi be to far apart

You can see this phenomenon on the 77 bus which used to be a streetcar run [there were until recently still some tracks buried in Mass Ave in Arlington]
There are several 5 or 6 story apartment / condo blocks along Mass Ave west of Arlington Center -- at 77 bus stops in that area the bus can fill/empty in a couple of stops

even for a large metropolitan university like BU or Northeaster -- the density of "commuting" varies a considerable amount throughout the campus -- and since that part of the B Line is all about servicing BU -- the stops should be appropriate to the demand
The thing is, in the BU area, there are a lot of options. BU runs (or at least was running) a shuttle that basically replicated the B line+ went to the med campus. On top of that, the 59 makes even more stops. And theres Hubway as well. Never mind most students walk.

That doesnt take into account services aimed exclusively to those with disabilities, which provide door-to-door service.

Edit: Free BU service


Schedules
Charles River – Medical Campus (1BU)

Monday Friday: 6:00am to midnight, 10 minute peak service, 20 minute off-peak service
Saturday: 6:30am to 7:00pm, 30 minute service

Comm Ave Loop (COMM)
Monday – Friday: 7:00am to 7:00pm, 10 minute service


Night (NITE)
Monday – Thursday: 10:00pm to 12:30am, 15 minute service
Friday: 11:30pm to 12:30am, 15 minute service
Saturday and Sunday: 7:00pm to 12:30am, 15 minute service
 

F-Line to Dudley

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Copley to Hynes is 3,000. Could be 2,500 if they could be bothered to open the existing closed entrance. Clearly, they dont care, so why is it so important to keep the B stops at ~1,000?

Just because its easier to build stops above ground doesnt mean its needed. Ive never heard anyone complain that the subway stops are too far apart. D line stops are all over 2,000 apart, and everyone agrees it's the best line. Additionally, South Street to BC is 2,500, with a closed station in the middle. That was also a well-liked change.
The Green Line isn't amenable to flat-world stop spacing, assuming demand even skewed across all 4 branches to total generica there...which it most certainly does not.

(1) The stops are variable on demand, so dwells--even on a longer platform with all-doors--start to become an issue around BU if you combine too many stops and too much multi-stop demand in one place. It's already an issue, for example, at Harvard Ave. which does the second-highest boardings behind Longwood of any reservation stop and has some particularly nasty time-of-day crush loading. The Comm Ave. Phase III Reconstruction design is going to have to find a way to come up with a wider platform, because the minimum-width current platforms choke on simultaneous boarding/alighting movements in such a way that more doors are not going to help enough with all foot-traffic converging on one set of crosswalks at one single end of the platforms. BU Central and Packards--the stations abutting this current consolidation zone--are at risk for much the same congestion backfires if consolidation goes too aggressive in-between...and both of those sitting at busy intersections means dwell management is all the more critical for hitting a transit priority-signal + queue-dump slot. I think you can argue about +1/-1 stations within those margins...but total scorched-earth will most definitely impale itself as far as the dwells v. transit priority dance is concern.

(2) On the shared-traffic branches you eventually get diminishing returns the more traffic signals you have to time going commando between stops. It's why expressing was never thoroughly deployed back in the day even with a BERy/MTA that was way ops-smarter about that kind of stuff. With proper stop priority you are going to need to tap a queue-dump timing mechanism every few signals to set the table, or else you're simply not taking full enough advantage of that priority. Carlton, BU Bridge, St. Paul, Pleasant, and Packards are the 5 mixed-traffic signals you must engage to traverse the consolidation zone. Under optimal timing you're probably not going to be able to barrel through any more than 2 of those most of the time...3 maybe *some* of the time...without hitting a red that exceeds the window for transit priority.

(3) The last round of "well-liked" stop consolidation 20 years ago hit stations that were genuine ridership craters compared to their adjacents, signaling a dead-obvious utilization problem calling for culling. The Blue Book shows no similar-size craters here with exception of South vs. Chestnut Hill Ave. (reposition to Foster St. is probably in order for the future), which brings Problem #1 to the fore if there's too much over-consolidation. And that last round of cuts were largely stops between traffic signals, where there were no signaling speed-ups to be had and the open-running actively cut against future signal priority gains. Greycliff Rd., the spacer you cite between South & BC, has a traffic signal only for the ped crossing and Evergreen Cemetery private driveway. It's always a green light absent extreme low-volume force changes from the driveway or crosswalk, and in a future-phase Comm Ave. reconstruction would be a grade crossing targeted for outright elimination. There's no comparison to the cross street signals between BU Bridge and Packards Corner.


If speeding the time-on-clock across the entire corridor to BC were the be-all/end-all goal here--which it isn't, because only a fraction of riders go that far--that's what something like supplemental D's via Reservoir & Chestnut Hill Ave. are for rather than bludgeoning the roster of well-patronized intermediate stops. But there isn't enough demand to initiate an alt-pattern like that, because the corridor is so thoroughly hyper-local. The best solution they can reach for amid conflicting audience aims is to tighten the bolts while toeing a line that does not veer off into extremes. You're not going to ever get reference-spec perfection in the B line; it has to serve too many masters. Just tighten its very loose set of bolts with optimizations so it runs the best it can for all it has to do and so it stops creating chaos upon entering the subway. That's the middle ground GLT shoots for.
 
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HenryAlan

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Now...keep in mind BU East/BU Central spacing is still all fucked up at 500 ft. apart and no room on BU East to extend the platforms for Type 10 'supertrains' sans permit to close the Cummington Mall grade crossing.
Would it make sense to eliminate the Blanford stop, and shift BU East to the block between Silber Way and Granby?
 

whighlander

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Would it make sense to eliminate the Blanford stop, and shift BU East to the block between Silber Way and Granby?
Henry -- if this is verging into "Crazy Transit Pitch" territory

the T should just dig a deep tunnel to go under the Turnpike all past PACKARDS CORNER [the fork between Comm Ave and Brighton Ave] with:
Station just before BU Bridge [about where the current BU Central]​
Station just before the current Packards Corner surface station​
Station at Harvard Ave​
coming up to a surface station at or near to the Griggs St surface station​


That would get rid of most of the light-related problems as well as the issues with small platforms
 

F-Line to Dudley

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Would it make sense to eliminate the Blanford stop, and shift BU East to the block between Silber Way and Granby?
No. (1) Blandford Yard makes shifting the BU East platform impossible. (2) If you've ever been around Kenmore after a Sox game you know how much Blandford (and, correspondingly, Blandford Yard) is absolutely needed. That and the swells of BU students between classes give it a robust 1500+ daily ridership. (3) Distance-wise it's a league-average 1350 ft. nearest Kenmore headhouse to Blandford crosswalk, so also isn't an outlier on spacing. The only consolidation you'd ever see here is if Urban Ring LRT built the subway out to BU Bridge with a BU East intermediate stop...in which case the would-be flanking egresses of BU East Under would probably hit Marsh Plaza and Hinsdale St. closing up the between-stop spacing in a way that crosswalk positioning does not. But of course you have to be committed to building the UR as an LRT appendage for that to go on the table.


The GLT working group hasn't publicly announced their slate of changes for platform lengthenings east of BU Bridge, in part because the will-they/won't-they question of MassHighway squaring up the BU Bridge intersection makes said Green Line plans highly variable. If you're operating on assumption that MassHighway is eventually going to come around to the intersection do-over, then Blandford-BU Central probably shape up like this in the future:
  • Blandford. Grade crossing closed, platforms extended west over the crossing footprint to 250 ft. regulation 'supertrain' length (i.e. extension to about dead-center of the current crossing). Fencing installed at left-lane curbs, plantings berm eaten to widen platform to fullest extent. Crosswalk retained at north side of intersection, Comm Ave. EB drivers directed to Kenmore uey lane for reaching Silber Way; Comm Ave. WB drivers directed to new-graded uey lane (i.e. curb turnout so explicitly separate from crosswalk) at Granby St. Intersection stoplight changed to on-demand ped signal. Subway signal system extended from portal to Granby St. so Blandford Yard goes under direct control of central dispatch, is more easily available as a run-as-directed staging area for plugging headway gaps without needing to stage an inspector onsite at the switch hut.
  • BU East. Close Cummington Mall grade crossing...extend west (double-egresses @ Granby & St. Mary's grade crossings). As per Blandford, new graded uey lane on the east (non-station) side of the Granby intersection. Delete old BU Central. Replace with graded Comm Ave. EB-to-WB uey ramp (more on that next).
  • BU Central. Change BU Bridge/Mountfort intersection to single-point with left-turn lanes. Mountfort becomes full 2-way. Comm Ave. WB reduced from 4 lanes to 3 (1 protected left, 2 thru, 1 permissive right) with eliminated weaving. Carlton St. grade crossing closed, Carlton St. reduced to right-turns only (same Comm Ave. EB-to-BU Bridge NB and Mountfort-to-Comm. EB movements as today). Univ. Rd./Storrow EB access uses the new St. Mary's uey lane. BU Central rebuilt as facing platforms abutting the compacted intersection, 250 ft. platform spreading across sealed Carlton intersection. Way more equitable spacing, both to BU East and to *new* St. Paul. TOD jump-start to air rights parcel over Pike on Carlton and BU Academy with the sprawl compacting.
So in addition to the 'feng sui' re-spacing, you also net -3 traffic lights (Blandford, Cummington, Carlton) for a LARGE performance improvement on this extremely congested stretch.


Alas...if MassHighway doesn't bite the bullet on an intersection compacting the Plan B options are a lot kludgier all-around, at least as East/Central go.
 

F-Line to Dudley

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Henry -- if this is verging into "Crazy Transit Pitch" territory

the T should just dig a deep tunnel to go under the Turnpike all past PACKARDS CORNER [the fork between Comm Ave and Brighton Ave] with:
Station just before BU Bridge [about where the current BU Central]​
Station just before the current Packards Corner surface station​
Station at Harvard Ave​
coming up to a surface station at or near to the Griggs St surface station​


That would get rid of most of the light-related problems as well as the issues with small platforms
Not totally Crazy Pitch. To interface with the Grand Junction at all with LRT for the Urban Ring, you are required to extend the subway to BU Bridge with a junction popping 1 portal out shallow-level to the hillside on the SW corner of BU Bridge, and another at Amory St. for the B and *new* St. Paul after it slices under the Pike. Simply no other way to square the level difference for an LRT interface, so that's an ironclad requirement (BRT Ring would have to plow under on different trajectory and portal-up on Mountfort, so construction costs in this area are either mode-neutral or slightly more favorable to LRT). Would be a cheap dig because it's 90% a dig under the 1890 reservation footprint with minimal utility relocation and would only have one inermediate station--BU East "Under"--spanning egresses built at Marsh Plaza and into Warren Towers. Flying junction somewhere right past the station as the UR stays level and cuts diagonal under Comm Ave. WB to hit the shallow bridge portal and the B descends down and straight for the underpin of the Pike. Assume Kenmore-BU Bridge then becomes some extension of Comm Ave. Mall with a cycle track on the restored surface.

If Kenmore-St. Paul are traversable in 3 minutes instead of 12+ you've solved 100% of the B's performance issues because all west of there is a piece of cake compared to getting between Kenmore and the other side of the bridge. There simply aren't enough nasty traffic signals past there to make the remaining 12+ surface stops any challenge worth continuing the subway any further past that. The biggest bang-for-buck with widest project synergies (B + UR-Kendall + UR-Harvard) is BU Bridge subway extension w/ flying junction...no shorter, no further.


Note also that if Comm Ave. Phase III reconstruction ever gets its act together on whether to center the reservation past Packards, you would have enough room to widen the problematically narrow Harvard Ave. platforms for dwell taming AND install another Blandford-style turnback yard past Harvard (eating the space for Griggs, and further consolidation maybe replacing the Griggs+Allston spacers with a *new* Long Ave. stop with revamped curb cuts). It would then be possible to stiffen headways on the busiest inner stretch, reduce them slightly on the ridership crater up the hill, and re-stiffen on the BC end with C's extended up Chestnut Hill Ave. to BC (doable with the -3 most obvious stop consolidations on the C trading out to +3 pickups on the outermost B). You would only need to flip Chestnut Hill Ave.'s facing platforms to the opposite side of the intersection and fix the too-close South St. spacer with a more equitable Foster St. one (swapping out deleted South grade crossing for addition of Foster grade crossing).

So there's also easy-reach future throttles for managing demand simply by diversifying the flexi-turn options.
 

jass

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The Green Line isn't amenable to flat-world stop spacing, assuming demand even skewed across all 4 branches to total generica there...which it most certainly does not.

(1) The stops are variable on demand, so dwells--even on a longer platform with all-doors--start to become an issue around BU if you combine too many stops and too much multi-stop demand in one place. It's already an issue, for example, at Harvard Ave. which does the second-highest boardings behind Longwood of any reservation stop and has some particularly nasty time-of-day crush loading. The Comm Ave. Phase III Reconstruction design is going to have to find a way to come up with a wider platform, because the minimum-width current platforms choke on simultaneous boarding/alighting movements in such a way that more doors are not going to help enough with all foot-traffic converging on one set of crosswalks at one single end of the platforms. BU Central and Packards--the stations abutting this current consolidation zone--are at risk for much the same congestion backfires if consolidation goes too aggressive in-between...and both of those sitting at busy intersections means dwell management is all the more critical for hitting a transit priority-signal + queue-dump slot. I think you can argue about +1/-1 stations within those margins...but total scorched-earth will most definitely impale itself as far as the dwells v. transit priority dance is concern.
Some if this is self-inflicted, with front-door boarding creating a full decade of extended dwell times. All door boarding (and vehicles with more doors) would help massively. Also adding frequency would as well. No reason you cant have a trolley every 4 minutes. But I agree that narrow stations are an issue as well. With Harvard, you could fix that by creating a crosswalk on the other end.

Of course, making the whole thing underground to Packards Corner, as was originally proposed 100 years ago is the best solution, and I hope no one would disagree with that. Shame our officials only care to make marginal improvements rather than real transformations.

Overall, these changes are good. They just could be better.
 

HelloBostonHi

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No reason you cant have a trolley every 4 minutes.
That would combine to a trolley a minute in the core section. Even with CBTC you'd struggle to run those headways smoothly without inevitable bunching and slowdowns.
 

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