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Post by metrocenter on Mar 26, 2010 9:18:47 GMT -8
The Downtown Connector project will extend from 7th Street/Metro Center to Little Tokyo, but the track by these lines will includes more than just this new track. It will also include the Flower Street segment between 7th Street and Washington Street. In particular, I am very concerned about Pico Station. This station is at-grade in a very busy part of Downtown L.A. In particular, I have three sets of concerns: - Capacity - The platforms at Pico Station are too small to handle large crowds. Unlike the current situation, once Expo and the Connector open, people are going to be riding multiple lines, going in different directions. This means far higher ridership than that station currently sees. This will be especially problematic on nights when multiple events are happening (game at Staples, concert at Nokia, convention, etc.).
- Traffic Impacts - 12th and Pico Streets are going to feel double the impact due to the high throughput of trains from multiple lines. With double the trains of typical Expo and Blue Line stations, there will be double the impact on cross streets. This not only affects cars but pedestrians as well.
- Access - Entering and exiting Pico Station by foot is awkward, due to the single entrance/exit that comes off the side. With more trains and larger crowds, it will only become more awkward and potentially dangerous.
I think Pico Station should be put underground, sooner rather than later. Making these changes will have the following benefits: - Capacity - An underground station at Pico would benefit from a larger center platform that can more flexibly accomodate large crowds.
- Traffic Impacts - An underground station at Pico would remove all impacts from 12th and Pico Streets, allowing better car and pedestrian access between South Park and the Convention Center district.
- Access - An underground station at Pico would have at least one (maybe two) entrances at key corners. One of these could be on the west side of the street, which would remove the need for people to cross Flower Street when going to/from events.
I don't know what the cost of such a project would be. But I think that if this is not done, Pico Station could become a big operational and safety problem within this decade.
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Post by ieko on Mar 26, 2010 9:57:04 GMT -8
I have to disagree with the traffic impact, the Pico Station actually doesn't see a lot of heavy traffic, even on event nights. Most of it is on Figueroa.
Beyond that though, something really does need to be done to that station, the entrance is awful for large crowds and the capacity of the station is too low. It may be unrealistic to put it underground for the near future though, that'd have to come with a massive overhaul of the downtown tracks, perhaps combined with a bigger push to put that segment underground.
Maybe there should be split platforms? There seems to be space for one on south of Pico.
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Post by bluelineshawn on Mar 26, 2010 11:46:52 GMT -8
I agree with metrocenter and disagree with ieko. Pico station ridership seems to me to have at least doubled in the last 2 years. Add in Expo and I expect that the current number will double again. Next add in the people of some number that will be transferring between blue and expo. It most likely won't be a huge number, but there will be some. Finally add in all of the new riders from the massive development projects proposed around the station (timeline uncertain) and the station will be very crowded. And it can sometimes already get bad trying to cross Flower on the 12th street side. When there are events you have not only train riders, but large groups of people walking from the various lots. Very often I see people start to cross against the light and then see how fast cars are coming and then stop. And when they do that they are standing on the tracks. I think that the sight lines are good enough that they probably won't get run over, but they will screw up the train schedule. That being said I think that the existing geometry would make it hard to add an underground station without severly disrupting both the blue line and Flower for a long period of time. It might be better to reconstruct the existing platform/station to make it wider and even add a pedestrian subway.
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Post by JerardWright on Mar 26, 2010 13:04:18 GMT -8
I agree with metrocenter and disagree with ieko. ... It might be better to reconstruct the existing platform/station to make it wider and even add a pedestrian subway. Recycling a post made on the vvery topic. I took this picture at the 2008 Laker Season openerHere's the adjacent property. It's the blue boxes in the image. Currently it is parking on the 12th Street side. The same can be made for the NE corner of Pico/Flower. The yellow zone is the second platform location. All Metro would need is a chunk of it as a Fare-control plaza. As there are large loads during and after games using the TVM's it maybe needed to have a larger zone like this to handle that demand. Adding on to Shawn's pedestrian tunnel idea, I was thinking would it be easier for patrons to purchase tickets AT Staples Center and or LA Live before walking to the station? Having a Metro Kiosk with a number of TVM's with Metro investing in good clear signage from Staples Center/LA Live to the Pico Station. This maybe something that can be utilized to reduce the demand for the TVM's at the station it doesn't fully solve the problem of pedestrians crossing 12th/Flower one that can be mitigated with traffic officers moving pedestrians crossing the tracks at busier Staples/LA Live events.
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Post by Jason Saunders on Mar 26, 2010 14:29:09 GMT -8
Under the "Not going to Happen" category I would take the TBM for the Downtown Connector and send it all the way down to Washington. Perhaps the new Pico Station could be built on Figueroa and a new portal built for the 7th Metro Transit center for the new tunnel.
In this manner the Blue Line can stay open while a new tunnel and Pico Station are built a block over and the same TBM machine could be used for this segment
Once the downtown connect is operational perhaps the former Blue Line Platform at 7th and tunnel segment leading to it could be used, with modification, for the new Pacific Electric downtown circulator Trolley. Trolley cars could be stored in the tunnel when not in use.
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Post by wad on Apr 1, 2010 4:01:38 GMT -8
Under the "Not going to Happen" category I would take the TBM for the Downtown Connector and send it all the way down to Washington. Perhaps the new Pico Station could be built on Figueroa and a new portal built for the 7th Metro Transit center for the new tunnel. One catch ... what about the slope where the Blue Line emerges to the surface? I think there's a way still to have the Flower stations undergrounded without having to close down Metro Center for years. You're right about keeping the TBMs. They will be put to good use. What could be done is to do the project in phases. The first phase would be to make the Blue Line temporarily above-ground for a few years. Build a set of tracks above the tunnel along Flower Street. Build a temporary platform next to Macy's Plaza and remove the left-most three lanes to use for the Blue Line above-ground. The next phase would be to seal off the portal near Pico and reinforce the tracks to tunneling can proceed beneath. The third phase is to build the stations. This way, the Blue Line can run mostly intact with little service disruption and a minimal need to terminate outside of downtown and run bus bridges. Once the trains are undergrounded, the tracks can either be removed or preserved for future streetcar service. Two other things I would add to this project: 1. A new Olympic Boulevard station. Yes, it would place a lot of stations close together, but it is downtown, where close stations are needed, and second, we need to relieve crowding pressure from a sole Pico station. With L.A. Live, the Nokias and the Staples Center, Pico can't handle the burdens of so many major public venues on a comparatively small platform. 2. A single Blue/Expo platform for the Grand/Trade Tech College station.
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Post by JerardWright on Apr 1, 2010 5:51:01 GMT -8
As I'm thinking about this post regarding a Pico Station upgrade. A thought occured to me, the only way this Pico station can be done is through a new grade separated alignment to replace the at-grade Washington Blvd Blue Line portion between LA Live/Staples/Convention Center to the Right of Way. Utilizing 12th Street with a stop or two in the Fashion District as shown in the sketch (a cleaner graphic will appear this weekend) and on Broadway this can tie that portion of Downtown with the rest of the transit network With the multiple LRT routes running to the area with the Regional Connector in place will help serve as an important connecting function. This will strengthen the link between FIDM, Fashion District and the Convention Center when they have Fashion Week as well as add capacity to the lines.
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Post by metrocenter on Apr 1, 2010 9:58:10 GMT -8
Jerard, I'm all for additional routes through Downtown. But it seems to me that a project like won't have a realistic chance, given the number of other projects in the region waiting for approval, and the near universal hatred of Downtown by people in the regions suburbs.
(Of course, undergrounding the Flower Street segment is expensive too, so maybe you're right.)
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Post by metrocenter on Apr 1, 2010 9:59:50 GMT -8
The first phase would be to make the Blue Line temporarily above-ground for a few years. Build a set of tracks above the tunnel along Flower Street. Build a temporary platform next to Macy's Plaza and remove the left-most three lanes to use for the Blue Line above-ground. The next phase would be to seal off the portal near Pico and reinforce the tracks to tunneling can proceed beneath. The third phase is to build the stations. This way, the Blue Line can run mostly intact with little service disruption and a minimal need to terminate outside of downtown and run bus bridges. I'd been racking my brain trying to figure out how construction of this thing might be done. Your solution is very good. Another way is to bore the new tunnel just west of the current tunnel, still under Flower Street, but all the way to Metro Center station. The tracks could then merge with the existing tracks before getting to Metro Center. Or, (more useful and for more $$$$), they could pass through an expanded light-rail concourse in Metro Center, at the beginning of a 4-track Downtown Connector.
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Post by ieko on Apr 1, 2010 11:55:46 GMT -8
It would be nice if the downtown connector had a small spur before 7th/metro so that future tunneling could be done with little disruption to service.
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Post by JerardWright on Apr 1, 2010 17:26:34 GMT -8
The first phase would be to make the Blue Line temporarily above-ground for a few years. Build a set of tracks above the tunnel along Flower Street. Build a temporary platform next to Macy's Plaza and remove the left-most three lanes to use for the Blue Line above-ground. The next phase would be to seal off the portal near Pico and reinforce the tracks to tunneling can proceed beneath. The third phase is to build the stations. This way, the Blue Line can run mostly intact with little service disruption and a minimal need to terminate outside of downtown and run bus bridges. I'd been racking my brain trying to figure out how construction of this thing might be done. Your solution is very good. Another way is to bore the new tunnel just west of the current tunnel, still under Flower Street, but all the way to Metro Center station. The tracks could then merge with the existing tracks before getting to Metro Center. Or, (more useful and for more $$$$), they could pass through an expanded light-rail concourse in Metro Center, at the beginning of a 4-track Downtown Connector. Folks, How much distance are we really talking about here? The existing tunnel for the Blue Line from 7th Street Metro Center to the 12th Street Portal is cut-cover. There are knockout panels at Flower and Olympic. It is all of 3 blocks between Olympic to Pico Blvd. They would have to construct the new underground station as cut-cover and they have to transition the line from this new underground back to at-grade before Venice since the distance between Venice and 18th Street I-10 on ramp is too short a distance. Also by the time they drop the TBM in they'll have to take it right out. So you're left with doing this segment as Cut-cover construction. But as I'm thinking of this, I need to take a trip to San Diego and see how San Diego Trolley does it for the Padres Home games at night at Petco Park Downtown. How do they manage to swallow the large pedestrian crossing demands of their at-grade station?
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Post by mattapoisett on Apr 1, 2010 22:41:41 GMT -8
The reason at grade for MTS and Petco Park works is there are 2 stations in proximity with 2 lines which go in 5 directions [The orange line loops around downtown and comes in on the back side of Petco as well] I am not sure if they run their special service from Petco to Qualcomm on Padres game days or only on Charger Game days that would technically add a 6th line. Plus there is a storage yard adjacent to the 12th and Imperial [Petco] transit center, which means they have the space and time to implement a plan of action. This is something Metro doesn't have at Pico Station
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Post by wad on Apr 2, 2010 3:02:38 GMT -8
But as I'm thinking of this, I need to take a trip to San Diego and see how San Diego Trolley does it for the Padres Home games at night at Petco Park Downtown. How do they manage to swallow the large pedestrian crossing demands of their at-grade station? I went last year to a day game and saw how it worked. (I didn't write up about it because the Surfliner broke down and took nearly 8 hours to go between San Diego and Los Angeles. All is well now. Amtrak refunded me ... twice.) San Diego has fortunately or fortuitously built in redundancies to handle crowds from Petco Park. The 12th/Imperial transit center has two separate boarding areas. The mainline area has at least 3 tracks. (I found this out the hard way as I saw the first track empty and a Trolley parked on the second track. I boarded the awaiting Trolley. I didn't realize there was a third track until I saw a northbound Trolley pull in. I got on a southbound train by accident.) This is where the Blue and Orange lines meet. There's also an east-west platform for the Orange Line that serves as its layover area. So Orange Line trains serve 12th/Imperial twice. The redundant stations are Park/Market, immediately north of 12th/Imperial. This is served by all trains. There's also the Gaslamp Quarter station for the Orange Line about 4 blocks west of the 12th/Imperial layover platform. Jerard, there's also this redundancy principle at AT&T Park in San Francisco. There's a main AT&T Park platform, there's 4th/King where the N and T lines split and meet Caltrain. There's also another station about 3 blocks east of the ballpark.
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Post by wad on Apr 2, 2010 3:07:27 GMT -8
I am not sure if they run their special service from Petco to Qualcomm on Padres game days or only on Charger Game days that would technically add a 6th line. I think the special event service is meant more for Petco Park service. San Diego told the ballpark to keep downtown parking to a minimum and use the existing downtown parking stock for games. In exchange, the Trolley would allow patrons to park at the old venue, Qualcomm, for free but pay a Trolley fare to ride in to downtown. I've seen Charger game days, and I've recalled the Trolley running extra-long trains.
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Post by wad on Apr 2, 2010 3:08:49 GMT -8
With the multiple LRT routes running to the area with the Regional Connector in place will help serve as an important connecting function. This will strengthen the link between FIDM, Fashion District and the Convention Center when they have Fashion Week as well as add capacity to the lines. I worry, though, that you get less ridership with this because you sacrifice the busy Grand station with Trade-Tech students and people going to the court on Hill Street.
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Post by JerardWright on Apr 2, 2010 8:33:44 GMT -8
With the multiple LRT routes running to the area with the Regional Connector in place will help serve as an important connecting function. This will strengthen the link between FIDM, Fashion District and the Convention Center when they have Fashion Week as well as add capacity to the lines. I worry, though, that you get less ridership with this because you sacrifice the busy Grand station with Trade-Tech students and people going to the court on Hill Street. Less ridership to maybe to Traffic Court. Expo would still serve LATTC at the 23rd Street Station the loss of ridership there will be MORE than made up for it through Ridership at Fashion District.
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Post by JerardWright on Apr 2, 2010 9:23:17 GMT -8
But as I'm thinking of this, I need to take a trip to San Diego and see how San Diego Trolley does it for the Padres Home games at night at Petco Park Downtown. How do they manage to swallow the large pedestrian crossing demands of their at-grade station? I went last year to a day game and saw how it worked. (I didn't write up about it because the Surfliner broke down and took nearly 8 hours to go between San Diego and Los Angeles. All is well now. Amtrak refunded me ... twice.) San Diego has fortunately or fortuitously built in redundancies to handle crowds from Petco Park. The 12th/Imperial transit center has two separate boarding areas. The mainline area has at least 3 tracks. (I found this out the hard way as I saw the first track empty and a Trolley parked on the second track. I boarded the awaiting Trolley. I didn't realize there was a third track until I saw a northbound Trolley pull in. I got on a southbound train by accident.) This is where the Blue and Orange lines meet. There's also an east-west platform for the Orange Line that serves as its layover area. So Orange Line trains serve 12th/Imperial twice. The redundant stations are Park/Market, immediately north of 12th/Imperial. This is served by all trains. There's also the Gaslamp Quarter station for the Orange Line about 4 blocks west of the 12th/Imperial layover platform. Jerard, there's also this redundancy principle at AT&T Park in San Francisco. There's a main AT&T Park platform, there's 4th/King where the N and T lines split and meet Caltrain. There's also another station about 3 blocks east of the ballpark. That's why I posed the question, because it will enable us to step back and analyze what the true issue here for Pico Station is and how that can be mitigated. Large Queues for purchasing fares:* Move the fare control since it is honor based using TVM rather than a paid staffperson, this maybe this can be placed in a special Metro Kiosk inside LA Live/Staples Center, similiar to what I hear is done at Charger Games at QualComm Stadium in San Diego. You take the bulk of those fares at the heart of the destination thus moving more people safely through the intersection and crossing. * Emphasize or adjust the Day Pass fare so it is more of bargain which would reduce the number of patrons needing to purchase one-way fares thus utilizing the TVM's. Platform Capacity:Platform waiting right now there is only one small platform to handle all the trips. The thing that can be approached is adding that redundancy by building a second platform, thus splitting the loads by 50%, reducing the risk of pedestrian collisions by that same 50% and adding significant capacity that is needed for these events. Train Storage/Operations:The bulk of these pieces have to do with operational methodology as shown with San Diego its a location where they can add extra relief trains as needed at special events. With the Regional Connector provides an opportunity to do that. One way is through the advocacy of having a long pocket track north of the 7th Street Metro Center station that will enable storage of a couple of trains, as the project has been further refined there's showing a greater need to include this into the project. Though it is not as close to the storage yards as the ones in San Diego it is a small piece that helps in the first bits of action. We'll have at least one storage yard north of Chinatown that can dispatch the extra trains (though it may take 12-15 minutes to get there) to relieve the gaps in the service and train loads in that one-hour window after the event. Another storage yard is the planned one north of the Washington Station on the Blue Line that can be used to handle extra demand to first shuttle patrons who will use it to transfer to the Red/Purple lines and then reverses back at 7th Street to continue to either Blue Line or Expo. These shuttle runs can be just that, trains that are not going the full trip but only go to the key load demand for example for the Blue Line they may only need to go to the Green Line or Del Amo (where there's a train yard). The key to this is effective communications and dispatching between the train operators, supervisors and storage yards. Even if this is an underground station, this would still pose the same headaches because at its core it's how the service is operated that makes the difference. A related example was when I lived in Chicago. The Red Line 'L' is the main transit corridor in Chicago it serves both Wrigley Field (Cubs) and US Cellular Field (White Sox). When both events let out at roughly the same time, the Red Line 'L' comes to a scretching halt though the line is grade separated. From experience having to come home from Crown Hall at night during the summer as a White Sox game ends usually added 20 extra minutes to my ride home because of operational delays of the operators not efficient in dispatching the train runs or having extra trains at a nearby sidings ready after the event.
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Post by wad on Apr 3, 2010 4:32:10 GMT -8
Less ridership to maybe to Traffic Court. It also handles overflow cases from the Superior Court in the Civic Center.
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Post by jeisenbe on Apr 7, 2010 17:55:03 GMT -8
I'm thrilled that the current alternatives for the Regional Connector include the excellent fully-underground option. But these discussions make me wonder if 2 light rail track through downtown are sufficient for demand. I keep hearing that the Blue Line is near capacity during rush hour. Of course, rush hour trains on the Blue Line run only every 5 minutes right now, so we can actually run twice as many 3-car trains if we want to.
But once Expo is finished, if the expected demand materializes, we will need trains every 5 minutes on Expo and every 5 minutes on Blue during peak hours. If everything works perfectly (which might require signal preemption for trains in Long Beach and Santa Monica, to avoid delays from traffic signals), we might be able to run trains every 2 minutes on the shared section, or every 4 minutes. So we can only increase capacity about 20%, if that. If the Regional Connector stations are built for 4 car trains, we could spend millions of dollars and enlarge blue line platforms to allow 4 car trains, to increase capacity another 33%, but the platforms in Downtown Long Beach and other places would have to be moved, due to the blocks being too short for 4-car platforms.
So what are we going to do if transit trip share increases from 11% to 20% in the next 20 years? The Blue Line and Expo line will be absolutely packed, which will make it even harder to stick to tight headways.
It would be relatively easy to add 2 more tracks to Flower by closing the street to car traffic, or 1 block over on Figueroa, if you don't mind building several new stations and platforms. However, the underground route from north of Pico to Little Tokyo is going to be carved into the rock at the cost of 2 billion dollars.
Let's not save 1 billion now, only to spend 4 billion in 20 years to build a third downtown subway.
Can someone at Metro talk to the Feds, and ask if we can recalculate the cost-effectiveness of a 4-track Regional Connector to take future growth and oil prices into account?
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Post by jamesinclair on Apr 7, 2010 19:04:04 GMT -8
Light rail can run more frequently that 2 minutes in a tunnel. Usually 90 seconds with a signaling system, 30 seconds or so with a visual system.
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Post by metrocenter on Apr 7, 2010 19:21:16 GMT -8
Will the tunnels for the regional connector be bored or cut-and-cover? Also, is Metro planning side platforms or center platforms?
If the tunnel is cut-and-cover with side platform stations, it would be easy at (comparatively) minimal cost to widen the tunnel for a third track down the middle, to allow for one-way express service between Little Tokyo and Seventh/Metro. Even better would be to add two express tracks. Little Tokyo Station could be designed with two platforms.
If this were done, the only bottleneck would be at the southern end, starting at Seventh/Metro. Eventually Metro would want to add a second north-south platform to that station, and give Expo a dedicated pair of tracks down Flower Street. But at least a major part of the system would be express-ready, when that day comes.
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Post by Justin Walker on Apr 7, 2010 23:45:36 GMT -8
Will the tunnels for the regional connector be bored or cut-and-cover? Also, is Metro planning side platforms or center platforms? As you can see below, for both underground emphasis options, the Flower St. segment would be mostly cut-and-cover and the 2nd St. segment would be mostly deep-bored. All the stations, except for maybe 2nd/Hope, would also be cut-and-cover. (Map from November 2009 DEIR/DEIS update presentation.) Based on project renderings and on AA report preliminary engineering plans, it seems that Metro is favoring center-platform stations, as well.
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Post by jeisenbe on Apr 8, 2010 1:17:02 GMT -8
Jamesinclair, I haven't heard of any system that runs light rail trains every 30 seconds. Our trains stop for about 20 seconds at each station, and the downtown stations will be busy. I know the Moscow subway runs some lines with 1 minute headways, but they are fully grade-separated and do not have branches.
The Regional Connector will have two separate routes meeting up. Both lines will be long and busy, and will be less than perfectly reliable due to traffic at cross-streets in Santa Monica, Long Beach, East LA and Highland Park. Each line will be 20 to 30 miles long (pretty impressive for light rail, compared to many systems around the world). It will be hard to stick to a 2 minute headway without tons of schedule padding. If the at-grade section along Flower, or at the Pico station, suffers from cross-traffic, it may be hard to run trains even every 5 minutes on each line.
Metrocenter, I think the plan is for deep, bored tunnels with deep cut-and-cover stations, though Little Tokyo will be a more shallow cut-and-cover station plus Y. So adding 2 more tracks would require TBMs with twice the diameter, or twice as many machines. Full cut-and-cover through that part of Downtown would be disruptive, to say the least. So I understand why Metro is reluctant to put in 4 tracks, although it think it would be wise based on a long-term outlook.
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Post by jeisenbe on Apr 8, 2010 1:19:57 GMT -8
Thanks for the clarification, Justin. What are you doing up this late? :-) Well, if the route thru the CBD is going to be cut-and-cover anyway, we really should advocate for 4 tracks. Little Tokyo got the all-underground alternative included. With the new federal standards for New Starts, it would probably still get a federal match, even with the extra expense for two platforms and four tracks at each station.
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Post by JerardWright on Apr 8, 2010 11:19:11 GMT -8
I'm thrilled that the current alternatives for the Regional Connector include the excellent fully-underground option. But these discussions make me wonder if 2 light rail track through downtown are sufficient for demand. I keep hearing that the Blue Line is near capacity during rush hour. Of course, rush hour trains on the Blue Line run only every 5 minutes right now, so we can actually run twice as many 3-car trains if we want to. That capacity shock is due to the layout of the platforms at 7th Street and the train crossovers and short pocket track area. There's not much room to manuever one busy line let alone two with such services with Expo Line to Santa Monica, so in essence the Regional Connector will relieve that key capacity bottleneck. Its the same thing that was done in San Francisco with their Muni Metro. Once they built the Embarcadero extension and added the long pocket track for turn back, that relieved capacity strains and significantly reduced delays for FIVE light rail lines. Or operate a "Drop and Catch" style at Willow Station, where demand south of this station for capacity beyond 3 car trains is very limited. "Drop and catch" works like this, when a full 4 car train enters the station, the last LRV car(or un-needed) is unhooked or Dropped from the main train. That car is taken to the turnback facility and switches to the opposite track and waits for the next train OR it holds at the pocket track north of Willow Station in order to catch the next train. The 4 track connector will balloon the costs of the project for the same number of riders as the current design with emphasis of crossovers at stations and the added long pocket track north of 7th Street Metro Center, which negatively impacts the Cost-effectiveness number. In addition, this will effect how much local money that needs to be contributed to the project in order to have the feds give a local match. The Regional Connector under Measure R has only $160 M allocated from it, with the rest coming from other projected sources such as HSR, so that extra $1B to the project will need to come from another source. One other logisitical issue to contend with and that is once the 4-tracks are reduced to 2 tracks at 7th Street Metro Center, where is your bottleneck still going to be? You guessed it, 7th Street Metro Center. Which means this will easily balloon to a $4 billion dollar project (based on the figure you used) because of unforseen pieces, such as; where do we continue this tunnel? How do you tie it into the existing tunnel? Where will the trains portal and how does that effect the existing operations? Where can we build temporary surface tracks. Also given how large Downtown LA is, we'll need a third subway or elevated line through to serve another area anyways.
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Post by crzwdjk on Apr 8, 2010 14:34:36 GMT -8
Moscow's Metro has a peak scheduled service of 39 trains per hour, and this is on lines with no branches. I would expect that for a properly designed, grade-separated Regional Connector, 24-30 tph should be possible. Designing for anything above that doesn't really make sense, because then you start to get problems with the lines feeding it anyway, with both the Blue and Expo lines having significant portions of street running, which limits headways. Increasing service enough to require a 4-track connector would imply some massive reconstruction of the existing lines first.
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Post by jamesinclair on Apr 8, 2010 15:34:10 GMT -8
Jamesinclair, I haven't heard of any system that runs light rail trains every 30 seconds. Boston, for one, in the underground section where the 4 branches meet. Trains frequently have to stop in the tunnel for a few seconds while the one in front closes the doors. As one train departs the station, the next will simultaneously enter. At stations with longer platforms, more adventurous conductors will edge in to try to fit. In san francisco, market street sees 30 second frequencies with buses and the f-line, and many times a bus and a tram will unload at the same time and then proceed through the light together. Again, this is without a capacity-crippling signaling system. The biggest bottleneck will be the blue/expo crossover because it is at grade and not a flyover. Trains in all directions will probably have to stop. I think the design was badly done.
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Post by erict on Apr 8, 2010 19:22:24 GMT -8
The biggest bottleneck will be the blue/expo crossover because it is at grade and not a flyover. Trains in all directions will probably have to stop. I think the design was badly done. I know the blue/expo crossover will be a bottleneck and an issue that will have to be addressed at some point. Add traffic at the intersection at Washington and Flower that can be backed up during rush hour and it just can't be good. But, we will have what we have I suppose, and it will just have to work until a solution presents itself. I suggested sinking Washington under Flower, but I bet there is a better way to deal with this yet-to-be problem.
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Post by jamesinclair on Apr 9, 2010 15:52:22 GMT -8
The biggest bottleneck will be the blue/expo crossover because it is at grade and not a flyover. Trains in all directions will probably have to stop. I think the design was badly done. I know the blue/expo crossover will be a bottleneck and an issue that will have to be addressed at some point. Add traffic at the intersection at Washington and Flower that can be backed up during rush hour and it just can't be good. But, we will have what we have I suppose, and it will just have to work until a solution presents itself. Yes, I dont quite understand where the signals will be and how they will work with the vehicle signals. Who will get priority?
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Post by Jason Saunders on Apr 11, 2010 13:10:09 GMT -8
How about this hypothetical:- Same TBM all the way. - Minimal disruption to blue/expo while under construction. - New larger pico station - closer to Staples/convention Center - Shared track is now grade separated. - Use existing 7th Metro station, just punch a new hole in the station.
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