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Old 05-21-2019, 11:51 AM   #681
F-Line to Dudley
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Re: MBTA Bus & BRT

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In Pittsburgh, buses merge into the *center* lane of an interstate highway from a full stop sign.

https://goo.gl/maps/8zNgCpT9oJ3f41oFA
Spurious comparison; that roadway in PA is grandfathered to fuck. The geometry on that whole deck is cosmically substandard by today's regs.

To add an all-new regular-service merge at the Ted it would have to be up to modern standards, or up to no later than the (99% modern) standards of 1995 when the roadway was built.
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Old 05-21-2019, 01:43 PM   #682
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Re: MBTA Bus & BRT

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Spurious comparison; that roadway in PA is grandfathered to fuck. The geometry on that whole deck is cosmically substandard by today's regs.

To add an all-new regular-service merge at the Ted it would have to be up to modern standards, or up to no later than the (99% modern) standards of 1995 when the roadway was built.
The complaint was that there would be a collision and MBTA would be liable.

If this was actually an issue, dont you think Pittsburgh would have rerouted the buses to avoid all these collisions? Or is the mayhem and carnage ok because its grandfathered in?
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Old 05-21-2019, 01:56 PM   #683
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Re: MBTA Bus & BRT

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The complaint was that there would be a collision and MBTA would be liable.

If this was actually an issue, dont you think Pittsburgh would have rerouted the buses to avoid all these collisions? Or is the mayhem and carnage ok because its grandfathered in?
Life is cheap on the mean streets of Pittsburgh!
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Old 05-21-2019, 08:14 PM   #684
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Re: MBTA Bus & BRT

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The complaint was that there would be a collision and MBTA would be liable.

If this was actually an issue, dont you think Pittsburgh would have rerouted the buses to avoid all these collisions? Or is the mayhem and carnage ok because its grandfathered in?
You're also comparing 40ft Diesel buses to heavy, dual mode, articulated, 60ft buses. Not only are they significantly slower (even slower than standard 60ft hybrids like SL4/5) they're longer and more difficult to merge. Same with the comparison to the 111 merge.
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Old 05-21-2019, 09:42 PM   #685
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Re: MBTA Bus & BRT

^ Ari Ofsevit had a long tweetstorm (and CommonWealth Magazine column) about MassDOT's "study" of the Seaport ramp.

He makes a bunch of great points, but one of his strongest (to me) is that a whole bunch of existing MBTA-used ramps (e.g., from Newbury St onto the Pike or from Chelsea onto the Tobin) are way shorter and have far worse sight-lines than the Silver Line Seaport ramp does.
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Old 05-21-2019, 11:10 PM   #686
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Re: MBTA Bus & BRT

Ari has been using a lot weird arguments on this issue, like saying that if 60ft bus can use a city street, it can use this ramp, or that if a 60ft bus can't use a ramp of a certain length, we should close all ramps of that length to all vehicles. Until he can stop using such hyperbolic comparisons, I'm going to tune him out on this issue.

Edit: And also saying that someone who doesn't have a commercial driver's license can't make any judgements about the safety.
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Old 05-22-2019, 06:20 AM   #687
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Re: MBTA Bus & BRT

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Dude take it from someone who's been at the conversations, state police have literally approved the use its just push back from some dudes at bus ops who are concerned about liability. Nothing would look worse than opening the ramp and getting into a crash, no matter how minor it would probably be. The MBTA has taken the position that its better to do this the safe and slow way, it has nothing to do with state police at this point. MassDOT owns the emergency ramp, they have the final say in who uses it.
For someone who’s “at the conversations” you seem fairly naive about this.
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Old 05-22-2019, 09:08 AM   #688
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Re: MBTA Bus & BRT

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You're also comparing 40ft Diesel buses to heavy, dual mode, articulated, 60ft buses. Not only are they significantly slower (even slower than standard 60ft hybrids like SL4/5) they're longer and more difficult to merge. Same with the comparison to the 111 merge.
The bus I was on when we went through that stop was a 60-foot bus. I dont recall what powered it.
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Old 05-23-2019, 08:33 AM   #689
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Re: MBTA Bus & BRT

Saw a trolleybus on the 72 (not in service) on the way to work this morning. It's been so long, that I honestly thought that the mbta quietly dropped the whole notion of using trolleybuses for diesel on that route.
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Old 05-23-2019, 11:49 AM   #690
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Re: MBTA Bus & BRT

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Saw a trolleybus on the 72 (not in service) on the way to work this morning. It's been so long, that I honestly thought that the mbta quietly dropped the whole notion of using trolleybuses for diesel on that route.
There was a wire issue that they had been chasing for over a year since the Huron Ave project finished. With the Harvard Tunnel rehab coming up soon, I'm not sure what their plan is.
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Old 06-03-2019, 06:26 AM   #691
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Re: MBTA Bus & BRT

https://commonwealthmagazine.org/opi...lectric-buses/

Comm Mag op-ed by Aloisi & gang urges reinvestment in the T's trackless trolleys, since full-on fleet turnover to battery-only buses needs to be slower to safeguard against implementation issues--mostly climate-related--that other cities have experienced. (Also a direct reply to last month's hot garbage op-ed from some think tank hacks arguing fact-free that we're not adopting batteries fast enough.)


I think it's a very solid piece.
  • The effects of New England winters on charging efficiency is a lede that should not be buried. Cold/wet is physically not a vehicle battery's friend, and heat--unlike AC--is the climate control power draw that can't by-physics see much additional efficiency gains. And it's worse for batt buses than diesels, because diesels use the engine's very energy inefficiency to recapture waste heat for keeping the passengers warm at lower electric load for the heating system. Electric engines, somewhat counterintuitively, are so efficient the heating system has to do all the heavy-lifting inside at much higher power. Technological evolution around these climate issues is still a work-in-progress. It's a favorable rate of progress, but still in-progress.
  • In no way/shape/form is it administrative cowardice to acknowledge that there are basic risks here, and to make damn sure that the battery pilots they order and test have an operating range sustainable long-term in all forms of weather. You can't figure that out without some substantial duty cycles on a smallish initial fleet with data collected over a several-year span (which the authors endorse). That's the practical prerequisite before plunking down on triple-digit yearly unit orders to overturn the diesel-hybrid fleet. Speeding it up because batts = ¡kewl! is irresponsible. As long as the FCMB is being realistic and honest at executing a sketched-out transition plan, there's no reason to get bent out of shape by the fact that this will take 13 years, not 2, to implement fleet-wide.
  • We also need time for a gap analysis of battery range shortfalls vs. the rate that battery bus tech is rapidly improving. The Moscow example cited of bus charges crapping out early (i.e. weather), high offtime for charging leading to daily fleet shortages, significantly higher number of buses required to cover the schedules vs. cycled charging uptime, etc. shouldn't terrify anyone because the tech is catching up. But Moscow (and Shenzhen) are big cautionary tales of taking the plunge too fast, without analyzing how the difference in uptime affects operating costs, and without doing systemic analysis of how long-haul vs. short-haul routes fare. In Shenzhen's case the costs in # of units was so much higher than planned that fleet-wide adoption is behind-schedule by years and are having subsidy curtailed for continued purchases. Purchasing batt buses at breakneck pace for the sake of fleet turnover Now!Now!Now! risks buying 1-2 technological generations of vehicle too soon for reliable systemwide deployment on a really big system.
  • The authors argue against the T's planned "batt"-stitution of the Cambridge TT's as a case of moving too fast. They cite:
    • Dirt-cheap operating costs, because TT vehicles are so mechanically simple and longer-lasting (up to 2-1/2 times) than regular buses that they more than absorb the premium from maintaining the overhead.
    • Superior all-weather performance. Because of deletion of fuel/battery bulk there's more room underneath and more weight savings to trade for additional wheel motors. 60-footer TT's wouldn't have to be banned in snow like their diesel/dual counterparts because there'd be more powered wheel sets gripping the road.
    • In-wire charging, in which a battery bus running on TT wires is charging the whole time while it's on-grid, is a potential solution to the range & offtime problems. And it limits the amount of trolley wire needed by concentrating that capital expenditure to mainlines, while branching routes can go off-wire. SL1/2/3 are dead-obvious applications because of the Transitway's existing overhead. But if the 77A wires, for example, were extended a shortish distance to Alewife (via the mythical Mass Ave. busways) the 77 could drop its poles at the Alewife Brook Pkwy. and run on battery to Arlington Heights and back without any range/downtime concerns. To counter the argument "Why build even a *little* more TT wiring if we're just going to be debating tearing it down in 20 years?"...this is why you *selectively* go for it: the more electric buses you can get sooner that don't have charging downtime between runs, the lower the overall Yellow Line's operating cost is going to be. If there is any idle charging whatsoever required, which figures to be the case for at least the next few batt bus generations because regenerative braking can't do it all...you will always need more units of batt buses than the equivalent diesels or TT's. The tech is quickly moving to a sweet spot where that units overage is trending from "stiff" to "very tolerable", but it's still an overage. The routes that can do absolute 100% in-wire charging will be significantly cheaper to run. Wires in Cambridge aren't icky-poo relics; they're money saved to reinvest in the system!
    • The authors argue for some places where in-wire charge TT's can be implemented on trunklines. Some of them, like the 28X, were proposed as TT's long ago. I'm not sure their analysis there is all that precise, because trolley wire is only cheap when a 600V DC source is nearby and I don't think they were thinking too closely about that. It's literally live under-street on the 57 (say, for a 71 extension to Newton Corner), the 39, and Washington St. south of Forest Hills. Places there's any nearby rapid transit hook-ins (e.g. spanning 77A/North Cambridge to Red Line/Alewife power sources) are also easily doable. This is because if there's an available 600V plug, any required substation upgrades can be distributed systematically (e.g. Red Line subs @ Alewife & Porter getting boosted for any Cambridge add-ons, or any number of Green Line subs slated to be upgraded for the GLT project being able to also power upgraded interconnects). But you have to be very choosy and limited with the candidate routes, because it's proximity to those interconnects that'll determine if the capital cost stays nice and low and lets the lower ops cost pay it back. They're out there, but it's a selective bunch.
  • The authors duly acknowledge that they EXPECT batt buses will close the gap as technology improves by leaps-and-bounds. But as response to that other op-ed, they stress the timeframe is what it is and that a stepped-out transition bridging the next +1-2 vehicle generations where they will be truly ready is paramount. In that transition the T should be covering all corners with the bus fleet, including another generation of the 100-years-proven TT's in increased numbers and concession that a share of diesel-hybrids will have to be strategically placed for some time to come. With the TT's it's primarily because their longer lifespan cover 2+ more generations of batt bus tech to where the batteries probably will have caught up. Instant gratification procurement is too likely to land us in Moscow's predicament.
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Old 06-03-2019, 09:10 AM   #692
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Re: MBTA Bus & BRT

100% agreed.

Trackelss trolleys are fantastic. Their biggest issue is if there is a crash or disabled vehicle and they cant get around it. A battery allowing 1 mile of off wire movement is all thats needed to make them perfect.
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Old 06-03-2019, 09:18 AM   #693
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Re: MBTA Bus & BRT

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100% agreed.

Trackelss trolleys are fantastic. Their biggest issue is if there is a crash or disabled vehicle and they cant get around it. A battery allowing 1 mile of off wire movement is all thats needed to make them perfect.
San Fran does that with their network. They need TT's because traction power + rubber tires slay all other modes on some of the steepest hills hosting thoroughfares. Since their streets are decently well-gridded a lot of the TT lines run parallel and are easily reachable via unwired cross streets. When they have to do scheduled wire maintenance they use the aux battery to triage between cross streets linking an alt-routed wired line. It's been a feature on their fleet through couple generations of purchases, though it's more limited in range than the full-on on-wire charging described here...owing to the older tech.

Definitely applicable here in some form or another.
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Old 06-03-2019, 12:22 PM   #694
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Re: MBTA Bus & BRT

This reminds me of a thing I've been wondering sometimes while sitting in overcrowded buses in the Transitway tunnel: Would it be possible to run both TTs and Green Line trains through the Transitway, if the Green Line was extended out that way? Unsure how the overhead would work, unless they put pantographs on the TTs and some kind of return contact on one of the rails.
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Old 06-03-2019, 01:21 PM   #695
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Re: MBTA Bus & BRT

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Old 06-03-2019, 01:51 PM   #696
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Re: MBTA Bus & BRT

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This reminds me of a thing I've been wondering sometimes while sitting in overcrowded buses in the Transitway tunnel: Would it be possible to run both TTs and Green Line trains through the Transitway, if the Green Line was extended out that way? Unsure how the overhead would work, unless they put pantographs on the TTs and some kind of return contact on one of the rails.

Dual panto/pole compatible hangers on the power wire (used on the Green Line mid-70's to mid-90's during the LRV/PCC overlap era). And TT return wire that's raised a few inches out of arc range from a trolley pantograph's surface. Used in several dual-mode installations worldwide with success.
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Old 06-03-2019, 02:42 PM   #697
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Re: MBTA Bus & BRT

A double articulated bus would provide a quicker, off the shelf solution to the problem and with platooning can actually provide even more capacity, without the years of disruption caused by a LRV conversion.




Just hope they don't drive them like this I already get my luggage flung everywhere on the Silver Line
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Old 06-03-2019, 03:03 PM   #698
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Re: MBTA Bus & BRT

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A double articulated bus would provide a quicker, off the shelf solution to the problem and with platooning can actually provide even more capacity, without the years of disruption caused by a LRV conversion.


Just hope they don't drive them like this I already get my luggage flung everywhere on the Silver Line
That's not the point of bringing LRV's into the Transitway. It's the one-seat to downtown and avoidance of crushing Red to death with double-transfers. They couldn't build SL Phase III because of the cost blowouts, wouldn't have been able to operate it thru-and-thru anyway (Washington and Seaport ends are forced loops at Boylston because of the excruciatingly slow speeds), wouldn't have been able to include Blue or northside Commuter Rail transfers as any part of the overall load relief, and wouldn't have been able to include much routing variance to offset the other demerits.

Since a second stab at correcting Phase III's fatal flaws must hook into something, and that something happens to be the LRV'ed Green Line...duh, the mode from the downtown direction is going to be LRV. It has nothing to do about gee-whiz vehicle tech or someone's personal favorite mode, and everything about having to be anchored to an extant 'thing'--and the mode that thing runs on--to do its stated job in a way that's can actually get built at all this time. I'm baffled as to why that's so hard to understand. Nobody's proposing operating the as-is Transitway route as a detached LRV dinky. The aim is to end its days as a malformed stub by hooking it into the integrated downtown transit system...not mulling a mode change while keeping the malformed stubbiness.
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Old 06-03-2019, 03:26 PM   #699
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Re: MBTA Bus & BRT

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That's not the point of bringing LRV's into the Transitway. It's the one-seat to downtown and avoidance of crushing Red to death with double-transfers. They couldn't build SL Phase III because of the cost blowouts, wouldn't have been able to operate it thru-and-thru anyway (Washington and Seaport ends are forced loops at Boylston because of the excruciatingly slow speeds), wouldn't have been able to include Blue or northside Commuter Rail transfers as any part of the overall load relief, and wouldn't have been able to include much routing variance to offset the other demerits.

Since a second stab at correcting Phase III's fatal flaws must hook into something, and that something happens to be the LRV'ed Green Line...duh, the mode from the downtown direction is going to be LRV. It has nothing to do about gee-whiz vehicle tech or someone's personal favorite mode, and everything about having to be anchored to an extant 'thing'--and the mode that thing runs on--to do its stated job in a way that's can actually get built at all this time. I'm baffled as to why that's so hard to understand. Nobody's proposing operating the as-is Transitway route as a detached LRV dinky. The aim is to end its days as a malformed stub by hooking it into the integrated downtown transit system...not mulling a mode change while keeping the malformed stubbiness.
That goal leaves low income SL4/SL5 riders with pretty poor options. My wild dream is that Phase 3 could be made to work, maybe not as originally planned, but in such a way that people at Dudley can get a one seat ride to the Seaport/Airport. Specifically Dudley to Logan which is a rather high demand route for airport employees. Going LRV makes that pretty impossible in the next 40 years until idk maybe an F branch to Dudley?

Other point, a large portion of the Silver Line's funding comes from Massport, and they can and do offer up the big bucks to improve service. They want more capacity to Drydock and Logan and they want it now, as nice as LRV may be for a Focus40 goal, improving BRT can and should happen now.
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Old 06-03-2019, 05:34 PM   #700
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Re: MBTA Bus & BRT

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That goal leaves low income SL4/SL5 riders with pretty poor options. My wild dream is that Phase 3 could be made to work, maybe not as originally planned, but in such a way that people at Dudley can get a one seat ride to the Seaport/Airport. Specifically Dudley to Logan which is a rather high demand route for airport employees. Going LRV makes that pretty impossible in the next 40 years until idk maybe an F branch to Dudley?
Since when did Roxbury have an unnaturally high travel orientation to the Seaport and Airport? Sorry...that's a wild reach of magical thinking right there. Thru-and-thru demand was one of the smelliest things about the shotgun marriage of "equal-or-better" Orange Line replacement and Seaport transit when they first came up with it. Then they stopped promoting that utility altogether when the tunnel design started going underwater on schedule performance and everyone was forced into a bus-to-bus transfer at Boylston Under Loop. It became a two-seat trip whether you built Phase III with its loop transfer or built off the Green Line outer tracks with a cross-platform transfer. The powers that be obviously weren't believing their own hype that Dudley-Logan or Dudley-Seaport one-seat was some #1-with-a-bullet travel pattern. And two decades of time passed has not given any additional credence to it in the form of tangible number projections. Logan--BECAUSE of broken links in the neighborhood-to-Downtown transit connections--still retains a workforce that tilts a little heavier to the North Shore than any other single region of the metro area...because there are fewer broken links/transfers on that end of the compass vs. some of the other neighborhoods and innermost 'burbs.

40 years? I fucking hope not, because that means we've failed to connect the Seaport to all the downtown transfers and you can kiss further growth in the CBD goodbye as everything gridlocks. If, in your own words, a do-over of Phase III that actually works at a buildable price qualifies as the stuff of "wild dreams", then we better be willing to widen the search for a solution rather than getting too-precious about mode choices. As I said, LRV is only the prevailing consideration because the Green Line is the closest thing to hook it into. If some other extant BRT thing were the closest available, then obviously that would be the choice instead. That shouldn't be so hard to understand. Something/anything downtown that's already there with some available orientation to hook it to means interlining is possible in a way Phase III and the forced loop transfer totally belly-flopped on. Kvetching about price is also a useless exercise here; the BRT tunnel already suicided itself on design-related cost blowouts. If picking back up, it's quite literally impossible to do worse than Phase III did on cost scoring or project timeframe. Anything that attempts to be an undead project by direct-addressing what killed Phase III so very dead will start out in a more favorable place by default.

Quote:
Other point, a large portion of the Silver Line's funding comes from Massport, and they can and do offer up the big bucks to improve service. They want more capacity to Drydock and Logan and they want it now, as nice as LRV may be for a Focus40 goal, improving BRT can and should happen now.
Completely and utterly irrelevant statement, because tracks aren't going to get laid in the Ted. SL1 will continue as BRT looping at South Station, with Massport funding shares probably being much the same as ever. Airport travel from downtown was never a problem because the Blue Line has always been there (excepting Red which still lacks the Blue connection, but SL1 plugs that gap). Seaport travel from downtown is where growth is gridlocking everything. Interlining into the Transitway stops and SL2 with higher-capacity vehicles directly addresses that. SL1 by and large works as intended for the audience it's intended for (unless you've got real math to show for that supposed top-priority Roxbury-Logan demand).

SL1's not the last word on Logan connectivity for everyone. Red-Blue offers up more balance. Hooking Green to Dudley sends those schedules into Gov't Ctr. where hitting Blue serves the same need for those Logan employees from Roxbury. And the Urban Ring NE quadrant--fileted either from downtown thru Lechmere/Sullivan (maybe even interlined with the Seaport) or from Cambridge on the Ring NW quadrant--eventually opens up the third direct option complementing the mix. I expect that particular build to take awhile, but the existence of the UR's northern quadrants as--surprise!!!--an easiest-feasible Green Line tie-in means there isn't some modal game-changer lurking inside an SL1 bus forcing reconsideration of how/where we hook all the other pieces together. Personally liking buses better than trolleys or wondering what decade we're going to wake up and fund something doesn't change what the interfacing mode is for actually getting somewhere through the transfers on the system.
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