MBTA Buses & Infrastructure
- Thread starter Arlington
- Start date
The EGE
Senior Member
- Joined
- Jun 29, 2013
- Messages
- 1,614
- Reaction score
- 4,022
Automation for heavy rail (or fully-grade-separated light rail, like the subway portion of Muni Metro in SF) is easy as noted. Fixed right-of-way, no cross traffic. Platform screen doors are desirable for fully driverless operation, but not required (Vancouver doesn't have them; BART has always had an operator for the doors.)
Light rail (either on-street or private ROW with grade crossings) and bus routes are definitely a promising possibility for driverless operation. While most of the general challenges of AVs are there, because crossings and traffic mean you have to identify and track moving objects, you're still dealing with a more limited physical area that it has to navigate. Bus route is all local streets and no expressways? Great, your AI doesn't have to have the ability to go on them.
With driverless operation and electric buses, there's an opportunity to greatly increase service at lower cost than today. Your per-mile costs drop down to electricity (relatively cheap) and maintenance/replacement cost of buses. Imagine routes that currently have 30-minute headways instead having a driverless shuttle every 5 minutes - the density threshold for "able to support transit good enough that you don't need a car" suddenly includes a lot of the suburbs.
Light rail (either on-street or private ROW with grade crossings) and bus routes are definitely a promising possibility for driverless operation. While most of the general challenges of AVs are there, because crossings and traffic mean you have to identify and track moving objects, you're still dealing with a more limited physical area that it has to navigate. Bus route is all local streets and no expressways? Great, your AI doesn't have to have the ability to go on them.
With driverless operation and electric buses, there's an opportunity to greatly increase service at lower cost than today. Your per-mile costs drop down to electricity (relatively cheap) and maintenance/replacement cost of buses. Imagine routes that currently have 30-minute headways instead having a driverless shuttle every 5 minutes - the density threshold for "able to support transit good enough that you don't need a car" suddenly includes a lot of the suburbs.
lainpimicaja
Active Member
- Joined
- Jun 28, 2021
- Messages
- 145
- Reaction score
- 552
I really think that chasing after driverless buses is terrible for addressing the short-term crisis. Why would you want to work somewhere (or be invested working somewhere) when the goal is to make your job obsolete? For the foreseeable future, we are going to need human operators, and the "what-if we replace these people with robots" conversation (on top of having a difficult, low-paying, under-appreciated job) encourages employees to leave very quickly. It's counter-productive for turning around transit and expanding service.
lainpimicaja
Active Member
- Joined
- Jun 28, 2021
- Messages
- 145
- Reaction score
- 552
Bus lanes going down on Huntington Ave near Brigham Circle, LMA, and Northeastern:
Yeah, it's fully a solved problem, and rather strange the new red/orange rolling stock with their associated new signaling systems don't support it. Another miss like not having the married pairs articulated.
Brattle Loop
Senior Member
- Joined
- Apr 28, 2020
- Messages
- 1,163
- Reaction score
- 2,077
This is more for the RL/OL transformation thread - but I believe F-line discussed how the new cars have to run on fixed-block ATO for the time in order to interlace with the existing older trains, but have the technology in order to run full-automated CBTC in the future. We might still always have a human operator on board to close/open the doors however..
MBTA "Transformation" (Green Line, Red Line, & Orange Line Transformation Projects)
An interesting tidbit from the B Branch upgrades: the old wooden ramps at Washington Street were removed. I don't think I ever saw those ramps actually used for access on the Type 7 cars once the worst of the bugs of the Type 8s got worked out. Given the mid-90's wood construction, almost...
archboston.com
And re: huntington bus/bike lanes.. this is a great step and I can think of plenty of 4-lane parkway-stroads in the area where two of the lanes should be converted in the same way. Just off the top of my head:
- Mass ave Bridge (convert the bike lane cones)
- Longwood Riverway and Jamaicaway
- Arsenal St in Watertown
- Mass Ave North of Porter Square
- D Street from Seaport to Southie
F-Line to Dudley
Senior Member
- Joined
- Nov 2, 2010
- Messages
- 9,185
- Reaction score
- 8,950
No, the system is still the same-old ATO it ever was...just optimized with more fine-tuning. You'd still have to install CBTC (and its considerable back-office computers) from-scratch if we were to ever do that. Where RLT/OLT makes things a lot easier is that it's replacing the copper cable backplane of the ATO system with high-bandwidth fiber to do the ATO optimizations. Fiber optic has the bandwidth to do all of the CBTC tricks when the time comes, so we get a large measure of down payment on the necessary field infrastructure. CBTC will still be very complicated in the back office, but the field hardware installations go a lot swifter and cheaper with pre-existing fiber bandwidth availability.
I keep on wanting a shared bus/streetcar transitway on Huntington where the buses and streetcars can share a transitway all the way from South Huntington to MFA. Hopefully this proves that they can reallocate the street space. then later do a shared bus-streetcar transitway and change the shared bus-bike lane to a full bike lane.
Has been discussed here pretty thoroughly, but, trying to put buses into the E's ROW would really degrade the E's service. It would be a pretty bad idea to share the green line with buses.
i saw some of the conversation, but, it seems like the issue is not really that a shared transitway is a bad idea, rather, the T is incapable of managing headways and service quality in an integrated manner.
Charlie_mta
Senior Member
- Joined
- Jul 15, 2006
- Messages
- 4,323
- Reaction score
- 5,940
Shared busses and LRVs are being done successfully in the downtown Seattle bus/LRV tunnel. The Harvard Square bus tunnel used to do this back in the 1950s, and hopefully the Silverline Bus tunnel to the Seaport district will do this someday.
Did they go back to that? I thought they stopped that practice.
Last edited:
I wonder if that calculus changes when comparing the radial 39 to the circumferential T39. A same platform transfer would be very useful rather than having people crossing the street to transfer from the T39 to the E to get to Copley/downtown.
Charlie_mta
Senior Member
- Joined
- Jul 15, 2006
- Messages
- 4,323
- Reaction score
- 5,940
Ha, you're right. I hadn't been there in a few years but they stopped bus usage in 2019 (which were several bus lines), so it's LRV only, in anticipation of the expanded LRV system currently under construction. I still think a shared roadway LRV/bus lane could work for one LRV line and one bus line.
Interesting. I always figured that if the transitway had rails added that would mean taking out the buses. SL1 really should be Logan Express, SL2 would get gobbled by the LRT, but I could see the argument for continuing to run the SL3 through the transitway. (I also think that Red-Blue + Logan Peoplemover would result in a decent decrease in SL demand through the Ted.)
Last edited:
Summer Street Pilot Program
The South Boston Seaport Strategic Transit Plan (SBTAP) is an ongoing planning effort. That planning effort will make recommendations for bus and rail access improvements to the Seaport. Early community feedback has highlighted the need for near-term improvement along Summer Street. We plan to...
www.boston.gov
In a world where LRT has connected to the transitway I'd assume that means SL2 is getting green'd...would it make more sense to run airport/chelsea service in the transitway or in the center running bus lanes mentioned above?
Fwiw, my understanding is that this is something the city really wants to do but massport is doing a lot of hand wringing.
Summer Street Pilot Program
The South Boston Seaport Strategic Transit Plan (SBTAP) is an ongoing planning effort. That planning effort will make recommendations for bus and rail access improvements to the Seaport. Early community feedback has highlighted the need for near-term improvement along Summer Street. We plan to...
In a world where LRT has connected to the transitway I'd assume that means SL2 is getting green'd...would it make more sense to run airport/chelsea service in the transitway or in the center running bus lanes mentioned above?
Fwiw, my understanding is that this is something the city really wants to do but massport is doing a lot of hand wringing.
LRT in the Transitway notwithstanding, airport service should run via Summer St directly into downtown. Very few SL1 riders disembark in the Seaport, so there's no particular priority in serving the Transitway, but a combination of Summer St and Congress St bus lanes could provide a one-seat link between the Airport, the Seaport, South Station, the Financial District, Haymarket, and North Station, and provide direct transfers to all commuter rail lines, and all rapid transit lines.
I'm more on the fence about SL3. A decent number of SL3 riders do disembark in the Seaport. But as for Chelsea-Downtown commuters (ie those who could benefit from surface-running along Summer to enable through-running to Downtown), it's a pretty roundabout route to go via Eastie and the Ted Williams Tunnel, especially when there is a long-established, more-direct route that also serves more areas within Chelsea -- the 111 -- and which itself has a very clear path to improved access to downtown: transit lanes on the Tobin. (Beyond which you could extend the 111 from Haymarket to South Station and even Summer St -- see my first link above). But given that there does appear to be a legitimate Chelsea-Seaport and Eastie-Seaport market, and that through-running SL3 seems less beneficial, I think probably it's worth keeping SL3 in the Transitway for now. (Of course, if LRT service levels ever rise high enough, that would provide go reason for displacement.)