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DART D2 Subway

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TNWE
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Re: DART D2 Subway

Postby TNWE » 14 May 2020 10:17

muncien wrote:
TNWE wrote:
Parker Road wrote: I'm not against D2 at all, but I've come to realize it's a "regional" fix for a "local" problem.


...
Recall that the original D2 plan had a tunnel branch east of Metro Center leading to a station at the Convention center that would have served this exact purpose, but idiots on here and at the public meetings acted like it was the dumbest idea DART ever had because "the tunnel doesn't go anywhere!!!" and DART staff didn't care enough to explain or defend the value of a terminus station to people who've never given even a moment's thought to how a train system operates (hint- trains can and do terminate in the middle of downtowns all over the world).


While I am not generally opposed to the idea of having terminus stations in downtown, I was vehemently opposed to DART's D2 terminus proposal. Having lived in Europe for years and utilized countless such stations, they are typically at the HUB of the city core and that is where most get on and off to access the city. They are beneficial in the fact that you have less pressure to find your train boarding time as there are numerous services at the station and your train will typically sit there for ten mins or so prior to leaving and you can always board early and get situation.
DART's proposal was to put it at the convention center and hotel. A place where six our of seven days any given week, is dead. You can't create a hub out of nothing... and therefore having a majority of inbound and outbound passengers boarding at neighboring satellite stations negates nearly all benefits of the terminus. Instead, it appeared to be a poorly disguised attempt to support (via massive tax $) an already tax $ heavy investment that was the convention center hotel. But instead of boosting the hotel (who does that with transit???), it would have been another massively empty boondoggle that the city is noted for.
Such a station under EMC would be far more beneficial. Or, deferring D2 and the terminus idea altogether until some game changer development like the previously proposed Smart District would make more sense.


In general, the CC Hotel area is pretty dead, sure, but in that case there was still the penultimate stop at Metro Center, where you could interchange with any other bus or LRT line- It's not like they were proposing a terminus in the middle of the Trinity Forest. For the sake of argument let's say that CC stub tunnel was just used for layover track and turning trains around - that makes Metro Center the terminus and it meets all the requirements of a good downtown endpoint.

My problem was with the people at the various planning meetings who couldn't fathom the idea of a train turning around (like they do hundreds of times a day at Parker Road, North Carrolton, DFW, Westmoreland, UNT-Dallas, and Rowlett). Everyone rightly complains about the LRT system being a downtown-centric hub and spoke model, but it's even worse than that - because every line is designed to run through downtown, they can't raise capacity to meet demand on any given spoke without also raising capacity on an opposite spoke that doesn't need the capacity (They do occasionally take SB Red Line trains out of service at Cedars, but that doesn't address the transit mall capacity issue).

Making a capital investment that enables real operational cost savings has a clear ROI, unlike the pie in the sky ridership and TOD projections that usually drive DART's major capital investment proposals. A subway station at Commerce street doesn't generate any new riders (all the AT&T employees are happy to walk from Akard), but makes D2 massively more expensive. The sooner DART builds the infrastructure that allows them to optimize frequency by spoke, the sooner they'll get their operational (i.e. ongoing) costs under control. So far, all their capital projects have steadily added to operational costs as more route miles require more trains and drivers, with no way to constrain added capacity to a single spoke from downtown.

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Tucy
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Re: DART D2 Subway

Postby Tucy » 14 May 2020 13:27

TNWE wrote:
Parker Road wrote: I'm not against D2 at all, but I've come to realize it's a "regional" fix for a "local" problem.


It's not even a *good* fix for the regional problem. The underlying motivation for D2 is that they can't add any more trains on any line because the current transit mall has capacity for 4 lines each at a 15 minute headway. The reason DART needs to add capacity is packed rush-period trains on the Red and Orange line between Downtown <-> Parker Road and the Green Line between Downtown <-> North Carrollton. With the current design, every train into downtown must exit the opposite side, so every additional AM train you add to handle Parker Road <-> Downtown crowds will run largely empty from Downtown <-> Westmoreland as it's going against the flow of commuters. Leaving aside track capacity issues, that's a hugely wasteful use of rolling stock and train operators.

The better solution would be to build underground terminus stations at the East and West Transit Centers (with accommodation for thru-running in the future) and have additional rush-hour trains from the Northwest and North Central lines terminate at those respective stations, then turn back to make additional rush-hour runs. Existing bus services or a future streetcar could connect both of those termini to the general vicinity of the Commerce Street station/Discovery District for far cheaper than the central tunnel section between Metro center and East TC, and when there's sufficient demand for more service outside of rush hour both north and south of downtown, DART can complete that central section and start running thru trains.


Better yet, build surface terminus stations at the east and west ends. Same result/massively lower cost.

And this is assuming that there are capacity issues that need to be addressed. I'm skeptical. I keep seeing references to overcrowded rail cars, but the ridership numbers just don't reflect any significant overcrowding; certainly not to any extent that won't be more than addressed by the completion of the conversion to 3-car trains throughout the red and orange lines.

I hear about overcrowded trains from Parker Road. DART runs 6 trains per hour during peak times. With 3-car trains and with capacity (per DART policy) of 165 per car, they have capacity for 2970 passengers in one hour (at the manufacturer's stated capacity of 279 per car, there's room for 5022 people per hour). In 2019, only 3295 people boarded at Parker Road in an average DAY. DART's trains, at their policy capacity, can handle the entire day's ridership in about 1 hour and 10 minutes.

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Parker Road
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Re: DART D2 Subway

Postby Parker Road » 15 May 2020 14:17

"Crowdedness" is definitely a subjective term that depends on the context of the system.

At least when I think about trains "from Parker Road," that really implies trains on the entire North Central corridor (north of Mockingbird) rather than from Parker Road specifically. As has been mentioned by several of us on this thread DART serves a regional/commuter rail purpose using LRT vehicles, and this is especially the case once you get further away from the core. The 2018 reference book shows about 15,000 average weekday boardings in this section, which is about on par with other regional/commuter oriented rail lines in the US. Nowhere near the amount of a busy local rapid transit line like in many cities. However, commuters and longer-distance regional travelers probably need more space on the train than, say, an urban traveler only going a few stops on a metro, tram, or local bus.

Anecdotally, rush hour trains along the corridor are reasonably busy—often standing room only, but not packed to the gills. I haven't had personal experience on other commuter lines at peak times to see if the situations are similar, but from the limited things I've read online this description seems to match other regional lines with similar ridership. Extra capacity for the sake of more frequent service along the outer corridors would be great for DART and invite ridership, not to mention lightening the crush on the downtown transit tracks, but there really isn't anywhere in the Metroplex where anything needs to be done to reduce heavy passenger loads.

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TNWE
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Re: DART D2 Subway

Postby TNWE » 18 May 2020 15:40

Parker Road wrote:"Crowdedness" is definitely a subjective term that depends on the context of the system.

At least when I think about trains "from Parker Road," that really implies trains on the entire North Central corridor (north of Mockingbird) rather than from Parker Road specifically. As has been mentioned by several of us on this thread DART serves a regional/commuter rail purpose using LRT vehicles, and this is especially the case once you get further away from the core. The 2018 reference book shows about 15,000 average weekday boardings in this section, which is about on par with other regional/commuter oriented rail lines in the US. Nowhere near the amount of a busy local rapid transit line like in many cities. However, commuters and longer-distance regional travelers probably need more space on the train than, say, an urban traveler only going a few stops on a metro, tram, or local bus.

Anecdotally, rush hour trains along the corridor are reasonably busy—often standing room only, but not packed to the gills. I haven't had personal experience on other commuter lines at peak times to see if the situations are similar, but from the limited things I've read online this description seems to match other regional lines with similar ridership. Extra capacity for the sake of more frequent service along the outer corridors would be great for DART and invite ridership, not to mention lightening the crush on the downtown transit tracks, but there really isn't anywhere in the Metroplex where anything needs to be done to reduce heavy passenger loads.


Yes- when I say Parker Road, I mean the entire corridor. Regardless of whether the extra trains are meant to ease crowding, or just increase frequency, there's no benefit to running every single train *through* downtown when the rush-hour ridership patterns are so heavily weighted to the northern part of the metroplex. All things being equal, I'd rather DART use their budget to run extra services on the parts of the line that are standing-room only in at least one direction, as opposed to running almost every train end-to-end. In the case of the Red Line, it takes 2.5 hours with layovers to cover 1 roundtrip (meaning 10 trains are required to run a 15 min frequency). It would be about 90 minutes roundtrip from Parker Road to a downtown terminus, meaning you could double frequency/capacity on the Red Line north of downtown by only adding 6 trains.

They sort of already do this via the Orange Line, but it suffers from the same problem- packed from Parker Road to Downtown, then empty all the way to DFW airport. On the return trip it might fill up some between Bachman and Downtown, but the Green Line typically runs 3 car trains during the peaks, so there's generally more capacity along the NW corridor in the first place. It's still a 3.5 hour roundtrip, with the train running mostly empty probably 2/3rds of that time. "Deadheading" is a necessary evil, but DART's current operations seem to maximize the amount of time peak capacity is running empty.

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electricron
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Re: DART D2 Subway

Postby electricron » 19 May 2020 00:26

TNWE wrote:Yes- when I say Parker Road, I mean the entire corridor. Regardless of whether the extra trains are meant to ease crowding, or just increase frequency, there's no benefit to running every single train *through* downtown when the rush-hour ridership patterns are so heavily weighted to the northern part of the metroplex. All things being equal, I'd rather DART use their budget to run extra services on the parts of the line that are standing-room only in at least one direction, as opposed to running almost every train end-to-end. In the case of the Red Line, it takes 2.5 hours with layovers to cover 1 roundtrip (meaning 10 trains are required to run a 15 min frequency). It would be about 90 minutes roundtrip from Parker Road to a downtown terminus, meaning you could double frequency/capacity on the Red Line north of downtown by only adding 6 trains.

They sort of already do this via the Orange Line, but it suffers from the same problem- packed from Parker Road to Downtown, then empty all the way to DFW airport. On the return trip it might fill up some between Bachman and Downtown, but the Green Line typically runs 3 car trains during the peaks, so there's generally more capacity along the NW corridor in the first place. It's still a 3.5 hour roundtrip, with the train running mostly empty probably 2/3rds of that time. "Deadheading" is a necessary evil, but DART's current operations seem to maximize the amount of time peak capacity is running empty.

DART is presently lengthening all the Blue and Red line platforms to accommodate 3 SLRV trains - just like the Green line. When this work is complete, there should be a 50% increase in capacity for each and every train during rush hours, as long as DART uses the 3rd vehicle. I doubt they really need a 100% increase in capacity considering they are already doubling the number of trains on this corridor with Orange line trains intermixed with Red line trains.

As for shortening the runs of the Red line trains, a pocket track is needed, or a spur off the mainline so the trains can turn around. A pocket track exists just prior to the spur to the south train yard south of Cedars does not shortening the Red line much, and every train turned is one less train servicing West Dallas. Doing so will cause a greater mess in the scheduling of trains than leaving things as they are.

As a reminder where DART has pocket tracks, there are just a few on the system. Green south at Lawnview, Green and Orange north at Bachman, Blue line north at LBJ/Skillman, Red line north at LBJ/Central, Red and Blue south just before spur to maintenance shops.

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Re: DART D2 Subway

Postby northsouth » 19 May 2020 18:40

electricron wrote:As a reminder where DART has pocket tracks, there are just a few on the system. Green south at Lawnview, Green and Orange north at Bachman, Blue line north at LBJ/Skillman, Red line north at LBJ/Central, Red and Blue south just before spur to maintenance shops.


There is also one just north of Victory.

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electricron
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Re: DART D2 Subway

Postby electricron » 20 May 2020 08:19

northsouth wrote:
electricron wrote:As a reminder where DART has pocket tracks, there are just a few on the system. Green south at Lawnview, Green and Orange north at Bachman, Blue line north at LBJ/Skillman, Red line north at LBJ/Central, Red and Blue south just before spur to maintenance shops.


There is also one just north of Victory.

Thanks for the additional pocket track location.

Additionally, I might need to explain why a pocket track is needed. So the train driver/operator/engineer can have the time to walk the length of the train between the cabs on either end of the train and have the time needed to properly turn off one cab and turn on and test the other cab - while not blocking the main lines.

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TNWE
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Re: DART D2 Subway

Postby TNWE » 20 May 2020 12:30

electricron wrote:
northsouth wrote:
electricron wrote:As a reminder where DART has pocket tracks, there are just a few on the system. Green south at Lawnview, Green and Orange north at Bachman, Blue line north at LBJ/Skillman, Red line north at LBJ/Central, Red and Blue south just before spur to maintenance shops.


There is also one just north of Victory.

Thanks for the additional pocket track location.

Additionally, I might need to explain why a pocket track is needed. So the train driver/operator/engineer can have the time to walk the length of the train between the cabs on either end of the train and have the time needed to properly turn off one cab and turn on and test the other cab - while not blocking the main lines.


Pocket tracks aren't strictly necessary for turning a train - almost every station has crossover rails, so as long as there's a back up driver ready at the platform and next train isn't due for more than ~10 mins, it's possible to turn a train at the platform (plus the signaling/ATP will prevent a following train from entering an occupied platform or blocking a crossover).

The primary purpose of a pocket track is for "warm" storage of stock near a station, for example the Victory pocket track stores the trains that will operate post-event Red/Blue Special trains so they don't have to deadhead & reverse trains from the yard near fair park - they can pull empty trains into the platform at Victory, then continue to their Red/Blue line termini. The LBJ Central pocket track stores extra trains during the transition in and out of the peak frequency, rather than having to deadhead everything back to the NWROF or CROF. The LBJ pocket is also used to turn some Orange Line off peak trains, but only because layover times are inconsistent and they don't want delays to cascade. Finally, any movement on to non-revenue track (which includes pocket tracks) requires DART Police/security to clear the train for safety reasons, which is at least as time-consuming as the operator changing cabs.

Bachman Station is unique in that it's not so much a pocket track as an extra track & platform at the station that allows for the Orange Line to operate as a "shuttle" between Bachman & DFW. That way the train can lay over without blocking the mainline operation, but still allow passengers to board at their leisure (e.g. to avoid the weather). DART can also use the central track as a "pocket" to clear the train of passengers and turn around, but that's only required if it's being taken out of service.

If Union & Pearl stations had a similar 3-track layout, DART could add rush hour capacity to Downtown, without adding more trains to the transit mall. There are definitely space constraints near Pearl, but I think there's adequate space near Union Station - they'd just need to take out the parking spots facing the NB Dart platform to add another track.

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electricron
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Re: DART D2 Subway

Postby electricron » 20 May 2020 23:55

TNWE wrote:Pocket tracks aren't strictly necessary for turning a train - almost every station has crossover rails, so as long as there's a back up driver ready at the platform and next train isn't due for more than ~10 mins, it's possible to turn a train at the platform (plus the signaling/ATP will prevent a following train from entering an occupied platform or blocking a crossover).

The primary purpose of a pocket track is for "warm" storage of stock near a station, for example the Victory pocket track stores the trains that will operate post-event Red/Blue Special trains so they don't have to deadhead & reverse trains from the yard near fair park - they can pull empty trains into the platform at Victory, then continue to their Red/Blue line termini. The LBJ Central pocket track stores extra trains during the transition in and out of the peak frequency, rather than having to deadhead everything back to the NWROF or CROF. The LBJ pocket is also used to turn some Orange Line off peak trains, but only because layover times are inconsistent and they don't want delays to cascade. Finally, any movement on to non-revenue track (which includes pocket tracks) requires DART Police/security to clear the train for safety reasons, which is at least as time-consuming as the operator changing cabs.

Bachman Station is unique in that it's not so much a pocket track as an extra track & platform at the station that allows for the Orange Line to operate as a "shuttle" between Bachman & DFW. That way the train can lay over without blocking the mainline operation, but still allow passengers to board at their leisure (e.g. to avoid the weather). DART can also use the central track as a "pocket" to clear the train of passengers and turn around, but that's only required if it's being taken out of service.

If Union & Pearl stations had a similar 3-track layout, DART could add rush hour capacity to Downtown, without adding more trains to the transit mall. There are definitely space constraints near Pearl, but I think there's adequate space near Union Station - they'd just need to take out the parking spots facing the NB Dart platform to add another track.

DART does not own the Union Station building, the City does and it leases it out to several entities that want parking spaces for their employees. DART could gain control of the property needed to run that extra track through eminent domain process, but I doubt the City would roll over. The City controls 8 of the 15 DART board members - and a heavy handed eminent domain attempt by DART would probably lead to 8 DART board members being immediately fired and replaced by the City at its next council meeting. :shock:

Whereas it is true trains can be turned without a pocket track, they would have to be turned on a mainline track. Crossover track switches are not placed between every station. The crossover tracks are located to allow single track operations with the trains moving normally, not with a train remaining stationary for the time needed to properly turn a train. With 20 minute headways on each color line, there is already 2 trains (one in each direction) every 20 minutes - averaging a train once every 10 minutes over a single track. After the color lines merge (at Bachman, 8th and Corinth, and Mockingbird, a single track line within these boundaries would average a train every 5 minutes. A single track line with 4 color lines in operation would average a train every 2.5 minutes. And that's during non-rush hour operations. There isn't 10 minutes between the trains on single track operations except where only one color train runs. Nearer downtown, after color lines merge, pocket tracks are needed - and guess where many of those pocket tracks are located? During rush hours single track operations will always have a potential for operational delays, no matter where or when.

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TNWE
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Re: DART D2 Subway

Postby TNWE » 21 May 2020 11:04

electricron wrote:DART does not own the Union Station building, the City does and it leases it out to several entities that want parking spaces for their employees. DART could gain control of the property needed to run that extra track through eminent domain process, but I doubt the City would roll over. The City controls 8 of the 15 DART board members - and a heavy handed eminent domain attempt by DART would probably lead to 8 DART board members being immediately fired and replaced by the City at its next council meeting. :shock:


I don't particularly care for any of the DART board members appointed by the city of Dallas, so that would be a win-win from my perspective! :lol:

On a serious note, having to find an alternate location for 20-30 parking spots is several orders of magnitude cheaper than the current iteration of D2. If the financial realities mean DART and the City of Dallas have to choose between living with the status quo for the next 10+ years or making a relatively modest investment to add a 3rd track & platform at Union Station (to allow Green/Orange trains from the NE to turn around) and in the vicinity of Pearl (to allow Red trains from the North to turn around), I think the city might find a way to convey a row of parking spots to DART. That would address capacity & frequency concerns on the outer sections of the lines without adding to the transit mall congestion, and there would still be thru trains running on all lines if someone on a terminating train needed to go to Akard or St Paul as their final destination.

But if the city of Dallas stomps their feet and continues with their "D2 or bust" posturing, it will be pretty clear that this 5+ year D2 saga was never actually about transit capacity or mobility, just appeasing a few unelected bureaucrats and activists who want to play SimCity with someone else's money.

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Re: DART D2 Subway

Postby cowboyeagle05 » 27 May 2020 14:48

To give the city council credit we are all playing SimCity with other peoples money. This whole forum is people with priorities, values and goals and desires playing a life long game of SimCity. Some more self beneficial than others. Every part of the bureaucracy is a multi level SimCity game.

For those who love SimCity but want something more up to date try City Skylines. I am addicted to designing my own parks, streets, neighborhood transit systems, street light configurations, road types. The game is so granular most people would laugh at you for caring that much about how many lanes there are and if they have bikes lanes, bus lanes or not. There is a reason I went to college for city planning.
“Growth for the sake of growth is the ideology of the cancer cell”


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