MBTA Buses & Infrastructure

whighlander said:
Build the next -- Super Station -- Underground Silver Line Way Station connecting with the tunnel under D Street -- this is a small amount of digging which can easily be packaged into Air Rights development of the existing Silver Line Way surface station and accompanying parking lot [Massport]
Some bureaucratic mumbo-jumbo is needed to merge properties from the two parts of the Commonwealth ostensibly in the transportation business [Massport and the MBTA] both technically report through the same chain to the governor
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RFP for Parcel H is already out from Massport. it includes air rights over the existing Silver Line way station.

Massport Puts Out RFP for Parcel H in Seaport

Massport's latest news and press releases.
www.massport.com
About Parcel H:
  • Parcel size of 46,500 square feet (1.1 acres);
  • Site is bounded by Congress Street, Starboard Way, Silver Line Way, and Port Lane;
  • Potential to expand the project site by an additional 62,000 square feet (1.4 acres) by overbuilding the Silver Line;
  • Overall potential for up to 600,000 square feet of transit-oriented, mixed‐use development;
  • Building height up to approximately 240 feet above mean sea level (approximately 230 feet above grade);
  • Opportunity for public realm improvements, including improvements to the MBTA Silver Line Way stop;
  • Parking available in Massport’s South Boston Waterfront Transportation Center (SBWTC), a 1,550‐parking space facility.
 
Is this Crazy: Build the Silver Line Way Station as a two-level station?

Lower Level "Inbound" from TWT...low enough that you could actually punch through the sidewall of the TWT (about here) and pull directly in from the Tunnel, rather than doing today's blocks-long loop on Congress St.

Upper Level "Outbound" to The Ramp...either surface level, or just a few feet under (with the new builder getting more street-level retail)

Both Levels connected to a D-Street tunnel.
 
Arlington said:
Is this Crazy: Build the Silver Line Way Station as a two-level station?

Lower Level "Inbound" from TWT...low enough that you could actually punch through the sidewall of the TWT (about here) and pull directly in from the Tunnel, rather than doing today's blocks-long loop on Congress St.

Upper Level "Outbound" to The Ramp...either surface level, or just a few feet under (with the new builder getting more street-level retail)

Both Levels connected to a D-Street tunnel.
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It would need to include a grade-changing, fully electrified loop-back for the SL0 transitway vehicles though.
Can the mode change be done at WTC? I was under the impression that Silver Line Way exists solely for that purpose and doesn't catch too much ridership.
 
sneijder said:
It would need to include a grade-changing, fully electrified loop-back for the SL0 transitway vehicles though.
Can the mode change be done at WTC? I was under the impression that Silver Line Way exists solely for that purpose and doesn't catch too much ridership.
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Yes. SL Way is just for the mode change...although the ridership isn't totally useless at about 900 and rising (vs. ~1200 & ~1600 for the other two non-terminal stops). That's where you get off to go to the Pavillion to see a show, visit Harpoon, stay at Renaissance Waterfront, work at the office towers on D, or hoof it to Black Falcon/Design Ctr. if you're not being picky about waiting for SL2 and just grabbing the first bus that arrives. It's going to trend towards more parity with the other stops the more that end of the neighborhood (and esp. all the commercial jobs TBD at Marine Terminal) gets built up. What'll happen is that if T-under-D ever happens you'll see a third full-on prepayment subway station built underneath 601 Congress, and the SL Way platform relocated about 200 ft. west under the 601 air rights so the existing open-air platform space can be cannibalized for a new incline up to the Haul Rd. light. They'd probably do the power switch there. By virtue of dropping the roadway into a deeper cut under 601 they'd buff out more side room for the platforms and the passing wires needed to protect headways should a bus happen to get stuck raising/dropping poles. That would be much harder to attempt at a WTC retrofit vs. clean construction because the wire turnouts in the tunnel are mostly there for rarer emergencies, not mundane everyday glitches like the three full sets of wire at SLW provide redundancy against.
 
Probably stupid question: Is there clearance/head room in TWT for the SL's overhead catenary to be run?
 
bakgwailo said:
Probably stupid question: Is there clearance/head room in TWT for the SL's overhead catenary to be run?
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No. Not with big rigs already running so close to the ceiling. The Ted is definitely where the battery buses will prove their mettle being able to continue to run on traction power after they detach from the continuous-charging tunnel wire.
 
F-Line to Dudley said:
No. Not with big rigs already running so close to the ceiling. The Ted is definitely where the battery buses will prove their mettle being able to continue to run on traction power after they detach from the continuous-charging tunnel wire.
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Ok, yeah, that is what I figured. Shame, though, as it would have been cool with Arlington's idea of directly tying in the inbound from the TWT to a new Silver Line Way stop (the switch to catenary could be done at the airport before entering the TWT). If say everything pre-TWT is wired up, and then the Airport is wired up, is there anyway to design the busses so that they don't need to manually switch from the pole? Then the battery could be for just the tunnel portion.
 
bakgwailo said:
Ok, yeah, that is what I figured. Shame, though, as it would have been cool with Arlington's idea of directly tying in the inbound from the TWT to a new Silver Line Way stop (the switch to catenary could be done at the airport before entering the TWT). If say everything pre-TWT is wired up, and then the Airport is wired up, is there anyway to design the busses so that they don't need to manually switch from the pole? Then the battery could be for just the tunnel portion.
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There's induction charging tech where driving over a metal plate in the road will do the charging. Dodgy prospect out in open air with the climate we have here, but would definitely work in the tunnel. The main questions are:
  1. Why change the catenary if you don't have to. The pole raise/drop is improvable with technological automation advancements like camera/sensor precision way better than when the current "fumble in the dark" method was designed in the very early-2000's, so the solution for making it go faster can be entirely self-contained on the vehicle and a 12 ft. length of overlead "sled". Jackhammering that infamous pavement for charging plates, running the trunk cabling, and safeguarding against all possible reliability intrusions (such as that infamously crumbling pavement eventually making the plate interface behave wonkily) is a very high-cost proposition for moving the same amount of electricity to the bus.
  2. If we truly want the Green Line to direct-connect to the Transitway to complete the festering-sore broken link to downtown after SL Phase III definitively proved itself unbuildable at acceptable cost, we'll need the dual-mode cat because the induction plates (and probably some other indirect-charging means) won't play nice with the return current on trolley tracks. Therefore if sensor tech can make the pole raise/drop "good enough" for the dual-modes, that's precisely what we need for future-proofing. And this doesn't require prognostication on when the Green Line is going to come to the rescue of canceled Phase III; Transitway future-proofing is an end unto itself as we chew on solutions for the Seaport mobility problem.
  3. Pure onboard regenerative braking charging is probably not good enough to 100% retire the tunnel wiring. Obviously battery bus tech is trending healthily more towards that direction, but there's been a lot of pushback to the overoptimism that they're a 2020's cure-all from case studies--particularly in cold/damp-climate cities--that charging efficiency still underperforms reference expectations due to overly variable ambient conditions (temps, HVAC load) and that adopting transit agencies have habitually underestimated equipment requirements (and thus costs for fleet sizes and maint facilities) due to the higher downtime of the vehicles. So cutting the cord is really not wise. If we've ruled out the Green Line for 30 years from now and then have flexibility to take down the overhead without causing future-proofing problems...2-3 generations from now the batt buses may be able to robustly handle it. But this is a decision we have to make sooner, so we don't know the future trajectory with anywhere near enough certainty.
All told, we're probably much better staying conservative here and keeping the overhead. As well as--if Urban Ring light rail is still a burning 20-year study consideration--stringing up cat on the Chelsea busway if a charging strip is needed at the other end of SL3. For the same future-proofing reasons as gee-whiz charging plates in the road are going to have to go away if trolley tracks get laid in that pavement from the Somerville side. As for Logan I'd love to see more effort at creating a traffic-separated busway at the terminals that's restricted to SL1, Massport shuttles, and Massport-blessed rental car shuttles only instead of running in mixed traffic with single-occupancy vehicles. That too could have charging overhead since a trolley plug-in from the UR is a natural far-future maximizing of that infrastructure. But it doesn't look like they're going there at all as the latest master plan is trotting out that nebulous APM concept and pushing the limits of single-occupancy traffic co-mingling to the terminal curbsides.
 
Yeah, I meant keeping the catenary (and possibly wiring up the airport) and make the pole switch automatic/not requiring a stop to switch to either battery (hopefully) or diesel for the tunnel portion, which would in theory at least allow a bus to exit the TWT right into Silver Line Way as proposed by Arlignton without having to worry about the switch over. Really doesn't seem like it should be difficult to have it full automated.
 
bakgwailo said:
Yeah, I meant keeping the catenary (and possibly wiring up the airport) and make the pole switch automatic/not requiring a stop to switch to either battery (hopefully) or diesel for the tunnel portion, which would in theory at least allow a bus to exit the TWT right into Silver Line Way as proposed by Arlignton without having to worry about the switch over. Really doesn't seem like it should be difficult to have it full automated.
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It probably would still require a pause because in-motion capture of swaying poles vs. swaying wires is asking for trouble even with Jetsons Shit computer tech assisting it. But unlike the extended layover baked in today at SL Way it can happen many times faster. One, the battery means the traction power can keep going and the hot-start of the diesel engine can be deferred to later (and that truly can be done in-motion). Two, the computers and sensors can manipulate the poles so much quicker. It's the same tech that you can buy in cars/trucks today for rear-view cams, semi-automated parallel parking, and hazard avoidance when backing into a garage and/or parking spot. Only here it's strictly applied to the pole lift motors and a sensor-guided visual of the overhead. 15-25 seconds is probably an effective target range for that unlike the 1-2 minutes it takes today. As schedule savings projected across headways projected across service day goes that is a LARGE increase in throughput.
 
F-Line to Dudley said:
It probably would still require a pause because in-motion capture of swaying poles vs. swaying wires is asking for trouble even with Jetsons Shit computer tech assisting it. But unlike the extended layover baked in today at SL Way it can happen many times faster. One, the battery means the traction power can keep going and the hot-start of the diesel engine can be deferred to later (and that truly can be done in-motion). Two, the computers and sensors can manipulate the poles so much quicker. It's the same tech that you can buy in cars/trucks today for rear-view cams, semi-automated parallel parking, and hazard avoidance when backing into a garage and/or parking spot. Only here it's strictly applied to the pole lift motors and a sensor-guided visual of the overhead. 15-25 seconds is probably an effective target range for that unlike the 1-2 minutes it takes today. As schedule savings projected across headways projected across service day goes that is a LARGE increase in throughput.
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And there is no reason why the changeover, with proper design, could not just be baked into the normal deboarding/boarding at the stop. Seamless.

It is a long separate kludge today, precisely because it is a kludge.
 
Worthwhile to point out that thus far what I've read from the T their goal is to 100% eliminate catenary from the whole route remember. According to the slides it's too expensive to maintain and causes operational issues. It also requires procuring special buses. That's why we have the pure battery buses and extended range hybrids testing on the SL trunk at the moment.
 
HelloBostonHi said:
Worthwhile to point out that thus far what I've read from the T their goal is to 100% eliminate catenary from the whole route remember. According to the slides it's too expensive to maintain and causes operational issues. It also requires procuring special buses. That's why we have the pure battery buses and extended range hybrids testing on the SL trunk at the moment.
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Irrespective of the way an electric motor on a bus is powered the Importance of SL-0 is that you can loop from South Station to an Underground Silver Line Way without interfacing with surface traffic once you get rid of the D-Street Crossing
 
whighlander said:
Irrespective of the way an electric motor on a bus is powered the Importance of SL-0 is that you can loop from South Station to an Underground Silver Line Way without interfacing with surface traffic once you get rid of the D-Street Crossing
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Absolutely, no dispute there. Was simply responding to some of the other discussion about wiring up SL3 or TWT etc.
 
Any desire to tear down the overhead has to be backed up by engineering analysis that the charging range can cover the whole route. Otherwise they won't do it. A lot of study refinement is having to take place for the batt bus adoption, because worldwide adoptions-to-date have grossly underestimated climate effects on charging ranges compared to optimistic reference examples.

The T doesn't know if they can take down the overhead, irrespective of that being a want.
 
Screenshot_20190923-175342_Drive.jpg
Screenshot_20190923-175728_Drive.jpg

Of general interest, the plans for new bus lanes look good for SL4/5 riders, although I take issue with them including Essex St in the "new bus lane miles" category when it's been a bus lane for over a decade just no one ever bothered to paint it.

And to F-Line, here's the slide from today's presentation about the plans for the new SL procurement. It's of note they didn't *once* mention dual mode fleets. They already have battery buses out there operating the whole route and they seem optimistic about the extended range electric hybrid which gets a whopping 4.8mpg.
Screenshot_20190923-180935_Drive.jpg
 
What is the "Alewife Access Ramp" mentioned as a planned 2019 project?
 
Arlington said:
What is the "Alewife Access Ramp" mentioned as a planned 2019 project?
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Based on description, I suspect they are going to try to restripe the Rt 2 off-ramp heading in to Alewife with a 2nd lane so buses can skip the traffic. Might be a tight fit.
 
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