MBTA Buses & Infrastructure

HelloBostonHi said:
Regenerative braking doesn't really care what speed you're stopping from or how often, it works on simple energy conservation formulas at the end of the day. And the MBTA already has tons of data on it, every hybrid mbta bus uses regenerative braking.
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Wrong!-- Google Michael Faraday or pull the trigger on a variable speed drill while holding onto the chuck

Regenerative braking occurs when the kinetic energy of the vehicle is put back into the battery [or the external power system] -- but in reality its the rotational energy of the wheels being converted into electrical energy by using the motors as generators. -- this is known as electrodynamic braking

This in electrodynamic braking -- if the wheels are not turning there is no generation -- and as the wheels turn faster the generation increases or vise versa as the wheels turn slower the generation decreases. To be regenrative the generated energy is used to recharge the batteries or fed back into the power supply through an overhead centenary or a third rail. The path from the generation to regenerative requires control electronics and lots of wiring all of which have electrical losses converting electrical energy to heat.

Eventually losses in the system means that there is no net transfer of energy to the battery [or external power system] -- at that point regenerative braking is useless. Note that you can continue to extract energy from the wheels at ever decreasing amounts as long as you just dissipate it as heat in a resistor. *1

However -- At some point the residual rotational energy can only be dissipated by friction [traditional brakes] if you want the vehicle to come to rest in a controlled manner

*1 -- the people who designed the PCC cars nearly 100 years ago knew all this except that they just used the generated electricity to brake electrodynamicly by dissipating the energy into a big honking resistor" -- it was electodynamic braking -- but not regenerative. At the end of the electrodynamic braking a cylinder pushed a brake shoe against the wheel
 
F-line, if you go back my apples to broccoli comparison was in response to jass asking why the MBTA is treating bus electrification differently than rail electrification. My response stated that it was because they are two completely different things. You've completely misunderstood me here, so I'm not even going to read that crap pile of text above this because it's based on inherently flawed interpretation of what I was saying. I rest my case, let's get back to discussing buses for the Christ's sake.


Arlington said:
What is the "Alewife Access Ramp" mentioned as a planned 2019 project?
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Noted on the MBTA alerts today that "On Saturday, October 19, the main entrance to the Alewife parking garage will close and temporarily relocate for repairs and upgrades."

Perhaps a correlation?
 
HelloBostonHi said:
F-line, if you go back my apples to broccoli comparison was in response to jass asking why the MBTA is treating bus electrification differently than rail electrification. My response stated that it was because they are two completely different things. You've completely misunderstood me here, so I'm not even going to read that crap pile of text above this because it's based on inherently flawed interpretation of what I was saying. I rest my case, let's get back to discussing buses for the Christ's sake.
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Your original response stated that BEB's were "ready to roll" while railway electrification was not, and tried to justify it with very spurious comparison of the top-line complexity of completely alien projects with completely alien amortization rates for paying off their investments. Don't mistake criticism of a deeply, deeply flawed argument rife with factual inaccuracies for "misunderstanding". Start by turning that personal aversion to crap piles of text to a little more self-awareness, first.

When you have real-world BEB installations that are missing their range targets by 30%+ in some cities but not others and no one has a good enough idea why to prevent the same mistake from happening, they aren't "ready to roll" on a wide scale. At all. There is no other modal comparison that fits, because no other mode is going through the technological growing pains of BEB first-adopters. You tried to twist an over-optimistic take on BEB suitability into direct comparison with unfinished decisions in the RER implementation study--which is still answering existential questions about what strategic direction they go, NOT what they could buy after they decide--as if those were question marks about the technology itself and product availability. That's utter bunk. This, this, and this have sterling service reputations in electric push-pull and are catalog-orderable right this second; the latter's compatible EMU power car variant is already on-order for large quantities from 2 agencies. There'd be more to shop around if Caltrain weren't running its Stadler KISS order of EMU's straight into the ground with dual-height door overcustomization and running the risk of having to cancel the order. Other Euro import possibilities also await under the new FRA regs if they don't want to take the easy/least-customizing way out by ordering 200 MLV's for the upcoming procurement then laundering some slush NJ Transit options to plug some EMU power cars into those coaches. Lineside it's all world-generic components following a federal specs manual...and infrastructure that fits entirely on the ROW property except for 30-mile spaced substations, to counter your wild overestimates of required property acquisition.


Then we've got this whole top-line cost fixation bereft of any underlying context. Yes, the whole package for CR electrification is expensive because--shocker!--it's an enormously higher-capacity mode shooting for an enormously-higher range. An armada of 20 BEB's doing Boston-Worcester at evening rush at equivalent of one Worcester train's capacity is not surprisingly going to have a vastly higher top-line price tag for adoption than just working some Key Routes in the Yellow Line's home district. Pricey lineside electrification also has decades-longer longer shelf life than the vehicles that run below the wire, with externally-powered vehicles longer lasting than their internally-powered counterparts (witness: TT's with a reliable lifespan of 25-30 years while all other buses are pretty thoroughly shot around 15 years), with readily midlife-rebuildable stock than buses that are slated to move to a more disposable 12-year replacement cycle. And given the rapid evolution of battery power, the garages (and possibly even the offline charging tech) are going to have to be re-equipped more frequently with each generation. Amortization ends up almost as important in the long run as top-line price on the initial capital procurement. That should be self-evident, but apparently not.

As before, we have no problem paying for pricey things if they are stepped out in advance on a CIP and can hold to their budget. We have enormous difficulty paying for things that blow out their projected budgets by several orders of magnitude. GLX pre- and post-reboot pretty much tell both sides of that story. The whole conundrum with 1st-gen BEB's is the debt-spending cities like Shenzhen--which even the Chinese gov't said "Enough is enough" on bailing out the overruns--are having to do covering the range shortfalls of their early-adopter fleets. And why no one's been able to wrap brain with certainty over why some cities have fared so very very poorly on charging ranges while some using the same bus makes have done better. It is pretty hard to see how railway electrification--higher top-line price and all--has similar catastrophic blowout potential unless we mismanage it two hands around necks like Caltrain is doing on all facets--lineside and vehicle--for its project. The smaller (but let's be clear: it's still all high-stakes $$$) top-line project that can't hit its projected budget on a dartboard is going to wither under scrutiny vs. the pricier (but 1000% differently-amortized) project that has little guesswork and a dead-easy chain of project mgt. blame if it does blow its budget.


That does not mean these projects SHOULD be compared...at all. Attempting to compare them is how the crap piles of text started flowing in first place. But if you are going to attempt to compare, exercise a little bloody context about the gigantic honking differences between the two and refrain from cherry-picking superficial garbage factoids.
 
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I see 14th St in NYC as being analogous to Congress St from Bullfinch Triangle to B St in the Seaport. I'd love to see a car ban on it in favor of bus, bike, delivery & "car pick up and drop off only"

Bus from NS/Haymarket to Seaport would be the missing link from everyplace that isn't South Station or the Airport.

www.nytimes.com

Relaxing, Weird, Beautiful: Riding the Bus on the New 14th Street (Published 2019)

All but banning cars on one of Manhattan’s busiest streets makes for a magical journey for buses. On another critical artery, they still crawl.
www.nytimes.com www.nytimes.com
 
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This is going back to a discussion on page 38/39 so I apologize for the late revival, but I stumbled across something relevant to the question of if the "State Police Ramp" onto the Ted Williams Eastbound was actually made for the Silver Line as has been strongly asserted by many. With the ramp being finally "piloted", it's less of an issue to debate, but the idea that the ramp was meant for the SL was hotly contested by some:
bakgwailo said:
I don't know if that is actually true and/or can be proven.
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This Boston Globe archive document describes (in the present-tense) the plan for Silver Line Phase 3, where the buses heading from Dudley would go below ground just North of the Mass Pike, tunneling under Boylston and Chinatown stations to continue on to South Station and then Logan. A relevant excerpt:
sl phase 3.PNG
 
I would question whether an MBTA/MassDOT press agent (I'm assuming the source for the story) saying there was an expectation the ramp would be used by the MBTA says anything about the intent of the design/construction from a decade before.
 
whittle said:
I would question whether an MBTA/MassDOT press agent (I'm assuming the source for the story) saying there was an expectation the ramp would be used by the MBTA says anything about the intent of the design/construction from a decade before.
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Yet, I would seriously question - first and foremost - the integrity of any design intent that didn't emphasize MBTA access
 
whittle said:
I would question whether an MBTA/MassDOT press agent (I'm assuming the source for the story) saying there was an expectation the ramp would be used by the MBTA says anything about the intent of the design/construction from a decade before.
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As mentioned before, the Federal DOT report on the Silver Line Project specifically called out that ramp as the Silver Line Ramp, and shows its use on the route.

I think the Feds know which ramp was meant for the SL (which they paid for) onto their interstate highway.
 
As it happens, this past week I've massively expanded the Wikipedia article about the Silver Line. (Comments, criticisms, and additional sources welcomed!)

As designed in the 1989 DEIR/1992 DEIS/1993 FEIR-FEIS, the Transitway was only to go to D Street; the documents don't mention access to I-90. (The possibility of Logan service directly from the South Station bus terminal is mentioned.) Not until 1997 when the Logan people-mover was cancelled was the D Street-Silver Line Way surface segment and the need to run to Logan added. The ramp, meanwhile, was mostly complete by 1995 (per aerials). The 1985 FEIR-FEIS for the Big Dig had very different ramp configurations in the Seaport than were actually built; unfortunately, I can't find any notices of project change that explain the reasons.

So if the ramp was designed for buses, it was probably done so unofficially, long before any actual plans for SL1. But we've known for a long time that it works with buses, even in traffic. The 2008 Urban Ring DEIR indicated that the ramp would be used, and a 2010 study found that it was safe to use.
 
The EGE said:
As it happens, this past week I've massively expanded the Wikipedia article about the Silver Line. (Comments, criticisms, and additional sources welcomed!)

As designed in the 1989 DEIR/1992 DEIS/1993 FEIR-FEIS, the Transitway was only to go to D Street; the documents don't mention access to I-90. (The possibility of Logan service directly from the South Station bus terminal is mentioned.) Not until 1997 when the Logan people-mover was cancelled was the D Street-Silver Line Way surface segment and the need to run to Logan added. The ramp, meanwhile, was mostly complete by 1995 (per aerials). The 1985 FEIR-FEIS for the Big Dig had very different ramp configurations in the Seaport than were actually built; unfortunately, I can't find any notices of project change that explain the reasons.

So if the ramp was designed for buses, it was probably done so unofficially, long before any actual plans for SL1. But we've known for a long time that it works with buses, even in traffic. The 2008 Urban Ring DEIR indicated that the ramp would be used, and a 2010 study found that it was safe to use.
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In 2006 after the Ted Williams Tunnel ceiling collapse -- only one lane was available as the TWT had a temporarily supported ceiling. During this phase of the reconstruction of the ceiling the normal access ramps from I-90 and the Seaport area to the TWT were closed and the SilverLine buses ran down the "Special Ramp" I made two round trips via the Silver Line during that period and there were no issues -- of course there was no merging as the regular I-90 traffic was absent
 
George_Apley said:
I'm going to suggest that bus reconfiguration convo redirect to MBTA Bus & BRT. Great convo, but at this point, this thread is best used for construction updates, images, etc.
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I actually took the 80 from Lechmere up to Pats towing on Mystic last Thursday. At 11 am the bus had 10 people on or off the route; especially along Main St.. I thought that was good ridership for the middle of the morning. The customer base was parents/nannies/babysitters with strollers. The route winds through amazingly tight streets, the driver was impressive.
 
HelloBostonHi said:
Finally news on the SL4/5 bus lane extensions and improvements. Full details are here: https://www.boston.gov/departments/transportation/silver-line-improvements-downtown but in summary all the SL4/5 bus lanes are being repainted, the lanes are being extended through Chinatown station and new restrictions through Downtown Crossing. Also new TSP along the route.
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is there someplace that shows a map/plan view of the changes (and not just a sample cross section)?
 
https://twitter.com/x/status/1192823277846220801

Did anyone go to this?
Of all the bus lanes, I think Warren St and Blue Hill Ave would be the most beneficial. They have some of the highest ridership paired with some of the highest delays. The streets seem to lend themselves well to bus lanes as well.

There also needs to be more than two bus lane enforcement workers. I took the Washington St one in Rozzie square every morning and I cannot think of a time where there weren't multiple cars, trucks etc. parked in the lane essentially making it useless (and honestly the commute longer because the bus would struggle to merge into traffic and back into the bus lane).
 
HelloBostonHi said:
MIT is doing some research on perceptions of bus infrastructure if you have a spare 5 minutes for a survey: https://urbanx.mit.edu/share/5AKIQS
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Shockingly poor survey design.

They ask my primary mode of transport: train. Now Im supposed to rank how safe these photos are but none of them include trains. Ok, fine, I can pick bus, ped, car or bike, but how do they know which one Im thinking about?

They dont define safety -traffic, crime or both?
 
It was a survey about BRT, so they weren't going to ask train questions. They just wanted to know what train people thought about the presented BRT scenarios, and whether that was different from what bike people thought, and what bus people thought, and etc. The only issue I had with it is that I couldn't accurately describe my transit usage. It's not as frequent as 2-3 times a week, but it is more frequent than 2-3 time a month.
 
Yeah I was noticing that as well. I think it could have used some more refinement.
 
HenryAlan said:
It was a survey about BRT, so they weren't going to ask train questions. They just wanted to know what train people thought about the presented BRT scenarios, and whether that was different from what bike people thought, and what bus people thought, and etc. The only issue I had with it is that I couldn't accurately describe my transit usage. It's not as frequent as 2-3 times a week, but it is more frequent than 2-3 time a month.
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I get its a bus survey, but thats not the question prompt.

The question says to answer from the point of view of your most used mode.
 
I was about half way through when I realized I was supposed to be viewing these pictures through the lens of my primary mode.
 
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