Lovely.

by j on Oct 13, 2009 10:32 am  

Although it's a beautiful plan, in the wake of this summer's crash, I doubt WMATA will have enough confidence in its signaling system to allow this anytime soon.

by Reid on Oct 13, 2009 10:39 am  

"There would be little downside."

As long as you have tremendous confidence in Metro's signaling systems.

In Chicago, the L makes 15 stops after O'Hare before it reaches the Loop. The Silver Line will make 14 stops after the Dulles before reaching downtown DC.

Additionally, lost ridership from intermediate stops would mean reduced frequencies.

In order for something like this to work, the Silver Line would probably need to put something like 500,000 daily riders into the system, not 70,000.

by David on Oct 13, 2009 10:42 am  

What time savings will this service offer?

It's a nice idea, but I suspect that it's probably not worth it.

by Alex B. on Oct 13, 2009 10:48 am  

If he had decent leadership, and good technology on the tracks, this would be completely possible. However, we are building tracks that should have been built 20 years ago, and have WMATA bozos who worry about getting money for schedules.

Conclusion: Never gonna happen.

by Jasper on Oct 13, 2009 10:51 am  

So, closed the italics.

by Jasper on Oct 13, 2009 10:51 am  

nothing is better in the long run than more redundancy.

If we have more tracks- and do not take the cheapskate route- we have more options.

Third tracks are a must for a system as busy as the the DC area system.

It would be the smootheset and most efficient way to increase ridership, put more trains on the tracks, and provide express service- and alternatives in case of emergencies. The resistance to having 3 or more tracks is ridiculous- and it stems from a wimpy mentality of not be willing to ask for the VERY BEST WE CAN POSSIBLY HAVE.

I say- give us 4 tracks on the Silver Line, and a separate commuter line on the WO&D.

This area needs more rail- not cheapskate penny pinching while we waste billions on new & extravagant highway projects.

Oh yes- and while we are at it- let's open the DC area Metro system 24 hours a day- especially for weekends- so that we can make drunk driving disappear.

by w on Oct 13, 2009 10:57 am  

So what's the pricetag on an extra express track? It's a given that it's cheaper to buy one now than ten years down the line, but how much will it cost in today's dollars? Because I don't see this region getting any LESS dense.

by monkeyrotica on Oct 13, 2009 11:05 am  

I agree on the signaling issue being a huge hurdle. Pehaps an express train could skip only the few lightly used stations.

by David on Oct 13, 2009 11:19 am  

I like the idea of a 3rd track being used like the directional center lanes of expressways that switch directions at rush-hour. In general terms how much more is it to build three tracks instead of two?

I understand there will be extra material costs, but all of the support costs and grading costs should only be marginally more as they are being done anyway (That being said tunneling would be much more expensive than above ground trains). Also, the administrative costs shouldn't be nearly as much as constructing a third line at a later date.

by Rob on Oct 13, 2009 11:20 am  

With four lines like that, you shouldn't need crossing over:

1) The Blue Line train peels off from in front of an Express at Rosslyn
2) This allows the Express to make up 2-3 minutes by East Falls Church, as it wouldn't have that train in front of it.
3) Then the Orange Line train peels off, and the Express can make up another 2-3 minutes.

That much can be achieved simply by having the trains in the right order. And I don't suspect you'd get more time savings than that regardless of what else you did.

But it still doesn't make it a good idea: I doubt there'd be enough capacity on the locals.

by James D on Oct 13, 2009 11:23 am  

Dan, I think you have good ideas, but in this case I don't think it's feasible.

When some in the Chevy Chase area called for a single-tracked Purple Line, MTA studied it. With six minute headways, they determined that any delay at all would cause major backups. That meant that someone holding the doors (or a door malfuntion, for that matter) at one station could start a cascading delay.

Now, I know you're not proposing a single-tracked Silver Line. But in effect, you are reducing the line to one track in several places by using the opposing track as a passing siding. With the Silver Line also having six minute headways, this proposal looks dead in the water. Think about how quickly delays start on the current lines when single-tracking goes into effect. Trust me, WMATA won't institute that as a regular rush-hour practice.

The only feasible way to make this work, I think, would be to install real passing loops at certain stations.

If the Phase II stations were designed with express tracks, your proposal might make sense. Express trains could leave Dulles Airport and have their own tracks to Wiehle Avenue. Merging back onto the local tracks, they could serve the platform there, allowing Tysons-bound passengers to transfer. Staying in the median of the Toll Road through Tysons (as Sandbox John proposed in one of the Silver Line threads) would also quicken the trip. Even better would be a redesign of the Wiehle Avenue stop to have local and express platforms and tracks.

But even with those improvements, without extra capacity in the core and Arlington, Dulles Express trains only serve to severely reduce capacity on the "local" Silver Line.

With the 135 second constraint at switch points (at Rosslyn and EFC), every 12 minutes, you can have 5.3 trains on each track. (Over 36 minutes, you get one extra train, so 16 instead of 15).

If we don't separate the Blue and Orange lines downtown, this means that every 12 minutes at Rosslyn, rush-hour makeup of trains (in each direction) would be 1 Franconia, 2 Vienna, and 2 Dulles/Ashburn. That means that the Blue (via Arlington Cem) would operate at 12 minute headways. The Orange and Silver Lines would each operate at a maximum of 6 minute headways. (12/1, 12/2, 12/2)

If you suddenly add a Dulles Express train to the mix, the formula is much worse. 1 Blue, 2 Oranges, 1 Silver, and 1 Dulles Express. I'm sorry, but 12 minute headways as a maximum for the rest of the Silver Line seems a bit low. Of course, you could sacrifice one Orange line train as an alternative, but then Vienna trains would come every 12 minutes, and that won't go over well, either.

by Matt Johnson on Oct 13, 2009 11:24 am  

What the stations need is a bypass track. With high speed switches, it would provide express service that could hop over local trains in a station. It would also provide a place to park a broken train. All it requires is a wider station design now or a tunnel under island platforms.

I also think stations should be raised up a bit, it would allow energy to converted into potential energy by climbing an incline rather than braking.

by shy on Oct 13, 2009 11:46 am  

skip stop is a disaster if there is no capacity for passing - skipping Tysons completely is the right thing to do! (as is upgrading Metro signaling...)

But to Matt's point on capacity: It should be noted that passengers taking the Silver line to Dulles would have a very different temporal ridership profile than typical commuters. The 66,000 passengers flying in and out of Dulles daily don't all need to get there at 9am or want to leave at 5pm and airport employees tend to work non-standard hours as well. Ridership to Dulles will be less "peaky" than the rest of the system.

This means that express service could be built and run to great advantage, even working around around current peak-hour capacity limitations (for example, an express Silver line could run at reduced frequencies frequently during the two daily peak of peak hours when Metro is at capacity, leaving more capacity for commuters).

by egk on Oct 13, 2009 12:26 pm  

with all of the naysayers against the idea of adding track capacity- I think it makes it even more of a desirable and possible alternative than the idiotic two track system designed for a city of the 1960's and a customer/user base way below our present day 700,000- 800,000 passengers.

I love it when people say it cannot be done- that is an automatic green light for any self-respecting American engineer or inventor with vision. And this is what we need- is VISION- not a lot of un-imaginative naysayers and book keeper types.

We in DC are second in passengers per day only to NYC and we need to be thinking not only of expanding lines to far flung suburbs but retro fitting existing lines in the core with more capacity- even if if means tunneling deeper, going below existing lines or whatever.

It has been done elesewhere and it can be done here.

People always forget how many billions we waste on roads and airports in the USA and how little pittance we actually are wiling to put out on more important projects like this idea.

by w on Oct 13, 2009 12:40 pm  

Additional track capacity isn't a technical problem that can be overcome with creative engineering. It's a bureaucratic/political problem.

On the other hand, squeezing capacity or speed out of an existing system *is* a technical problem that can be overcome with innovation.

by BeyondDC on Oct 13, 2009 1:09 pm  

yes - I totally agree- it is a bureaucratic /political problem.

However- adding lanes on a local highway does not seem to cause the same problems that adding tracks on our subway system seems to elicit.

We have to stop thinking in terms of roads and highways as the only viable transportation- and then all of this suddenly becomes feasable.

by w on Oct 13, 2009 1:16 pm  

w, adding lanes to roads is almost always contentious, as is building new roads. It is sometimes, but not always, easier than rail, but the widening of 66 or the ICC have been battles for nearly as long as the Silver Line has.

I'd love to have 4 tracks on the silver line, but it just doesn't seem practicable to me. I'd also like to have it tunnel under Tysons. That said, I'd much prefer to have 2 above ground tracks rather than nothing at all. I suspect that's the real choice we've been faced with.

The skip stop express sounds really good to me, though I question Metro's ability to implement it successfully. It seems to me it would require a massive signaling upgrade, and I just don't think they have the funds for it.

by jcm on Oct 13, 2009 1:55 pm  

If skip-stopping is possible in rush hour and at other times w/ minimal disruption, I don't see any reason not to do it, but I have a feeling it would be tough to implement and seem like a more bastardized solution in real-life.

by Vik on Oct 13, 2009 1:58 pm  

Small suggestion, but one that could increase ridership. Rename the Dulles Airport Station to "Dulles Airport/National Air & Space Museum" to point out to riders and tourists that the Udvar-Hazy center is right there. The fact that people have to drive out there and it still gets over 30,000 visitors a week leads me to believe that with the metro the number of visitors could double.

by Brian on Oct 13, 2009 2:08 pm  

The Air & Space museum is waaaayyyy at the south end of the airport, at the corner of 28 and Route 50. You'll still need a road shuttle to get there.

by BeyondDC on Oct 13, 2009 2:12 pm  

So who would you have to talk to (in one form or the other) to express this idea too?

by Zac on Oct 13, 2009 3:07 pm  

I love "shy's" suggestion that all stations should be elevated, in order to use gravity to aid braking and acceleration. I've thought of this myself, and can't believe it isn't standard practice.

As for the Silver Line express, yes, skipped stations ought to have a set of track hopping around the station, so non-express trains can wait in the station as the express trains pass. The time to decide is now, before construction starts! But it would be worth it.

And the Metro really should include stops for the Air & Space annex. Wolf Trap currently has a shuttle service from Metro, but I suspect the inconvenience makes it seldom used.

by Michael on Oct 13, 2009 4:54 pm  

The distance between the Dulles Airport station and the Air & Space museum is approximately the same as the distance between Georgetown and Capitol Hill.

They're not remotely close. Building a station to serve the museum would be like building a whole new line.

by BeyondDC on Oct 13, 2009 5:16 pm  

To do it right you'd need to do something like this that I just drew up: http://yfrog.com/ccdullesrapidmetroplanp

Create a separate boarding/charge areas for the rapid trains between Dulles and Ballston that you have to swipe through before entering the rest of the Metro system.

by NikolasM on Oct 13, 2009 7:07 pm  

Last link is not working... try this one. http://img444.imageshack.us/img444/1624/dullesrapidmetroplan.png

by NikolasM on Oct 13, 2009 7:10 pm  

@nikolasm I'm going to take issue with passing sidings at east falls church being easy or cheap to install. The station takes up the entire median of I-66 and would require eminent domain to obtain more right of way.

by Michael Perkins on Oct 14, 2009 2:43 am  

A few points:

*Right now, there are six places that require regular merging, and this would increase that to 26.

A track merge requires much more supervision and planning than managing an individual train - and WMATA didn't even feel comfortable leaving those to automated control.

*Adding tracks to built underground stations is quite hard. Adding tracks to built highway-center stations in the middle of the biggest traffic jams in the world is a lot harder.

*There will be conflicts between local and express trains. This will result in slowdowns or stops at times, for both. There is already a lot of adjustment because of the orange line merge and the Rosslyn bottleneck, this would make the system more chaotic (in the mathematical sense).

*In light of the rolling stock shortage, this would hurt frequency at the other stops.

*The Blue/Orange/Silver line has lots of stops. Do you propose to install passing loops there as well, or just shave 20 minutes off the trip to Rosslyn?

---

I'm all in favor of passing loops for redundancy and service de-interruption, I just don't think using them for a silver express service is all that practical. The net amount of rider time saved is probably quite small if it's even positive. Modifying the interior of the Dulles-serving cars for more cargo space is about the extent of the customization that seems feasable. Adding a third track seems like a much more productive activity, and adding a fourth has a lot bigger payoff than the third. Four-track lines with bypass switches at every station, and the potential to branch off or express wherever needed, seems like a good development model for future WMATA expansion through the core.

There is potential for a significant urban corridor to form around VA-28, if a strong enough trunk of bus routes is established(with a dedicated lane on 28) and enough office park sprawl is rezoned. The transit line would run from Manassas to Dulles Town Center, hitting the Silver Line, an expanded Orange Line, Udvar-Hazy, and about a hundred large parking lots. This would form the western border of the "urbanized" metropolitan area. Politically... Well, it's more likely than them building a rail siding specifically for Udvar-Hazy that gets 30 million additional riders over the next twenty years, which costs more than the $311M museum itself did.

by Squalish on Oct 14, 2009 4:52 am  

PS: It would have been nice if they could have curved the Silver Line south at VA-28 to meet the orange at Centreville, and turned it into one Big Orange Loop. If they'd done that, trains could operate as express in one direction, and all-stops in another direction. Once the Separate Blue line is built, trains could have operated on a Big Orange Loop with five minute headways in both directions, with significantly decreased trip times for most.

by Squalish on Oct 14, 2009 5:13 am  

Wouldn't be able to get the Silver Line up into Loudoun in that scenario, which if I'm not mistaken is one of the objectives of building the Silver Line...

by Froggie on Oct 14, 2009 8:43 am  

If you want to get into real long term planning, there's the Dulles Airport long term plan that includes (eventually) a southern terminal, fairly close to the Udvar-Hazy Center. That terminal would occupy the bottom half of the potential loop for Dulles' new people mover.

http://www.committeefordulles.org/pdf/080429_lebegern.pdf

Then, an Orange line extension might make more sense, along the rest of 66 and up 50. But this is a loooong time out, and Dulles still has a lot of room to grow within its current framework...

by Alex B. on Oct 14, 2009 9:26 am  

James D pretty much explains how the schema would likely work on the east end from Rosslyn to Tysons Corner, adding to that, Dan M. thinking, that locals should get out of the way of the express train make more sense then the express trains going around the locals.

As to the less then enthusiastic confidence in the signaling system voiced here. That in my opinion is a non issue.

Contrary to the believe of many here, the routing of trains around each other can be done automatically. All of the main line tracks are configured for bidirectional operation. Hell, the whole railroad could be switched to left hand running overnight.

The signaling system is designed to prevent head on coalitions. When a train enters a track traveling in the reverse direction of travel the next interlocking will automatically lock out any attempt to enter that section track by a train traveling in the normal direction of travel.

At present time WMATA has 12 unused destination codes in the 100 destination code table. 2 of the codes were assigned to the Dulles route when the destination code table was created back in the 1970s. At least 4 of the 12 codes will be used for the various other Silver line terminals. The 8 remaining codes could be used to route the local trains out of the way of the express train.

As far as I know there is no function built into the train board control system to automatically skip a station stop, there is however a manual function that cancels station stops.

by Sand Box John on Oct 14, 2009 10:13 am  

Michael, I drive by it everyday. There is enough room for a track around each side of the station.

by NikolasM on Oct 14, 2009 10:32 am  

An idea I have not seen discussed would be to run an express orange/silver line in the I-66 median (which I believe was the original proposal for the orange line) between East Falls Church and Rosslyn. And from East Falls Church again run an express line in the Dulles access road median that bypasses the Tyson stops and relinks with the Silver Line at the Wiehle Avenue Station.

From there to Dulles I'm not sure how to handle it but perhaps by the time they actually start building that part of the line the money/commitment will be there to have a third line combined with some of the ideas here to creatively build by-passes at the stations.

It is already a public right of way and you would not be building any stations and it is above ground so there is no tunneling either so this should cost a lot less than the current Dulles extension.

And funding wise it could be sold as an alternative to widening I-66 inside the beltway.

But the big catch here, and this is an issue that has been talked about rarely, is what to do with this line after it gets to Rosslyn.

But the problem of the Rosslyn tunnel and Orange/Blue line congestion there is a significant issue today and could threaten the success of the silver line assuming WMATA cannot sort out how to get these extra riders into the city.

So the primary conversation we need to be having is how to to get a new Rosslyn crossing built and a new Blue line through the northern part of downtown DC with stops in Georgetown, the West End, Farragut North and NoMa to connect with Union Station.

This new line could be built with 4 tracks to accommodate the local and express service.

So the express service would have stops at Dulles, Wiehle Avenue, East Falls Church, Rosslyn, Farragut North and Union Station.

This gets you fast single seat service from Dulles to downtown and I think enough riders would hop off the locals to the express trains that it would still leave some capacity for existing riders between Ballston and Rosslyn and it also adds enough capacity that you could begin a conversation about extending the existing Orange line from Vienna out to Centreville. A separate heavy rail line provides none of those benefits and of course is also not as integrated with the current system.

Cost wise 90% of the cost is in the new Rosslyn tunnel and stops in downtown DC. But I think those costs are inevitable anyhow as that part of the system is essentially at capacity now.

And I would pay for it by setting up a London style congestion tax in the core of downtown DC - this way the drivers paying the tax would see their money go to reducing congestion and thus rewarding them.

by TomQ on Oct 14, 2009 10:33 am  

Squalish, If your comments were directed at my drawing, I would not extend the Dulles Express past Ballston. It would be a Ballston to Dulles extra that works around the local silvers and oranges stopping at each end station in their own tracks. Users would have to transfer to a regular silver or orange line train (whichever was coming up next) to continue on into DC. I certainly understand that switching could be complex and perhaps a third/maybe fourth track in the Dulles Toll Road Median would be better, though it would be more expensive.

by NikolasM on Oct 14, 2009 11:05 am  

TomQ: the idea of metro running within the I-66 median towards Rosslyn has come up in the past on this forum. In a nutshell, it's a lot more difficult than you suggest because 66 has a narrow median east of Fairfax Dr, which would require a good bit of reconstruction to fit in Metrorail tracks. And then east of Lee Hwy/Sprout Run, the right-of-way gets really narrow so you'd have right-of-way impacts east of that point.

by Froggie on Oct 14, 2009 12:10 pm  

Here is the satellite view around EFC. In my opinion there is room for tracks around the station. http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=1900+N+sycamore+St+Arlington+VA&sll=38.885872,-77.156403&sspn=0.003178,0.004646&gl=us&ie=UTF8&hq=&hnear=1900+N+Sycamore+St,+Arlington,+Virginia+22205&t=k&z=17

by NikolasM on Oct 14, 2009 12:31 pm  

I'm pretty sure that the type of service suggested by Dan M (trains passing each other at stations on a two track bi-directional system) does not exist in the US or Canada. Is it used overseas???

I'm not an expert in these matters but it seems really tough. First, note the problems with cascading delays on a system like this. But also, how much time would you save? Metro switches are mostly quite low-speed diverging. Higher-speed turnouts require more maintenance ($, maintenance delays). Then, after you get the 8 car train through the interlocking, it has to go slow through the station, and back across another interlocking.

The scheduling gets pretty intricate, which can affect all the other lines.

I can see a skip-stop system, but as Matt J points out, this leads to infrequent service for others along the silver or orange lines. Ultimately the silver line is not about Dulles, it is about commuters in Tyson's and elsewhere, and Dulles. I hope WMATA keeps their focus on commuters, for a bunch of reasons.

Having said that, S Box John's Tyson's bypass is too logical to ignore!!! It would be really lovely to see the MWAA build the infrastructure in a way that this could be added on later without a lot of disruption!

It would be very cool to get Metro to think about trains that do not stop at every station. For Metro, this is like thinking about trains that fly. Trains stop at every station, period. At times, like after a disruption or during Obama's inauguration, this is ridiculous, but at Metro, trains stop at every station. WMATA is now deflecting the idea of adding (express) tracks to the core by saying it would be better to add parallel tunnels.

by DavidDuck on Oct 14, 2009 11:08 pm  

It is an interesting idea. I don't see how you could implement skip-stop on the Ballston to Rosslyn segement; I think there is too much train traffic.

The comments responding to this post, and also to the posts by Spencer and Matt, support a consensus that there are two distinct markets being served by the Silver Line, namely local and airport.

The Hong Kong MTR Airport Express potentially serves as a model for what the Silver Line might be. The Wikipedia entry is here - http://en.wikipedia.org/wiki/Airport_Express_(MTR)

The Airport Express is branded differently than the local Tung Mung line with which it shares track. Dedicated trainsets are utilized, and a premium fare is charged. Airport Express trains operate once every 12 minutes.

If the Tysons Bypass were built, it's possible for the only stop between between Dulles and Ballston to be Wiehle Avenue. That would result in significant time savings.

by PATCOrider on Nov 7, 2009 6:56 pm  

I was not an advocate of the 1/9 skip stop in NYC and I don't think it would have its intended goals met due to the confusion it would cause. Travelers need - very simple services. Complications lead to lost ridership.
I would advocate that the first step is to get the silver line in. The second step is to split the blue line out - but make the silver line run through it and keep the blue where it is.
The third step is to build express tracks on 66 between Rossyln and east of Ballston. As part of this build one single turn-back center track to allow some trains to terminate and increase the lines capacity.
Bottom line is each incremental improvement needs to then study how the rideship responds. An express service or skip stop to Dulles sounds like a good idea to pursue, but I would take reasonable steps with capital funds and make sure we are getting the biggest ridership gain with each investment and step we take.

by bob previdi on Nov 11, 2009 5:00 pm  

I have written to WMATA, as a former resident of the DC area, I have written MetroRail plenty of times over the years.
The problem, LOCAL trains are too dang slow.

The proposed idea on this blog is not new, in fact every single day it works perfectly in the Tokyo Metro area. I have lived in Tokyo after moving from the DC area, I have written WMATA letters saying they need to send inspectors out to Tokyo and see how they run their trains. IT IS AMAZING. Makes DC Metro trains look like toy kid trains. Many trains on the Tokyu Toyoko line run double track only, but with good proper scheduling, good signalling you can run express/rapid trains past local trains that are parked at local stations.

by tokyorailway on Jan 5, 2010 11:04 am