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Posts about Separate Yellow Line


AskGGWash: Why are Yellow Line trains terminating at U Street?

During rush hour, Yellow Line trains usually run between Huntington and Mount Vernon Square. But beginning in August, I noticed that many went all the way to U Street, two stops north of their usual ending point. The reason is a mechanical malfunction with a track at Mount Vernon Square that lets trains change direction, and the issue highlights just how important that track is to the entire system.

Photo by the author.

In technical lingo, the problem is called a "bobbing track circuit." The issue is typically considered more of a nuisance than an actual danger, but it's been preventing rush hour Yellow Line trains from accessing their usual turnaround point (the Mount Vernon pocket) for several weeks.

According to WMATA operations guru Stephen Repetski, a track circuit is described as "bobbing" when it erroneously flips back and forth between registering that a train is occupying its block when it might not actually be. This may occur because the circuit is too sensitive, or it may be due to old equipment that needs to be replaced.

A bobbing track circuit can cause trains to lose their speed commands. This forces the operator to stop and wait for permission from the Rail Operations Control Center to proceed to the next signal block, which they must do at a reduced speed. This significantly delays train operations.

WMATA signaling infrastructure. Photo by Matt' Johnson on Flickr.

Usually, rush hour Yellow Line trains reverse direction at Mount Vernon Square because there's a pocket track there-- a short third track located between the two main tracks, which allows trains to reverse direction without blocking trains on the mainline. In normal rush hour operation, Yellow Line trains use this pocket track to short turn, e.g. to turn around without running all the way to the end of the line at Greenbelt.

Since Yellow Line trains currently have to turn around using the crossover at U Street* (or run all the way out to Greenbelt), fewer trains are operating on the Green/Yellow Lines every rush hour. This is due to the fact that when trains have to short turn without the use of a pocket track, they cause delays by blocking trains in both directions, as Matt Johnson detailed in a 2010 post on the issue.

*There are crossovers that allow trains to turn around between every station from Gallery Place to Fort Totten, but Metro seems to have chosen U Street as the temporary turnaround point.

Trains that have to short turn without the use of a pocket impede through trains in both directions. Graphic by the author.

However, a pocket between the mainline tracks allows short-turning trains to be taken off the mainline while reversing direction, thus allowing through trains to proceed unobstructed. Thus, when rush hour Yellow Line trains turn back toward Huntington using the pocket track at Mount Vernon Square, they are allowing through trains (e.g. Green Line trains) to pass unimpeded on the mainline while the reversal procedure is carried out.

A pocket allows trains to reverse direction without blocking the mainline tracks. Graphic by the author.

This temporary "extension" of Yellow Line service did get a few Greater Greater Washington contributors thinking: could Metro ever permanently extend the Yellow Line past Mount Vernon Square during rush hour? Doing so would provide booming stations like Shaw, U Street, and Columbia Heights with increased service and a direct connection to Virginia at all hours.

There are, however, several financial and logistical problems standing in the way.

The obstacles: lack of a pocket track, railcars, and funding

After 15 years of short-turning Yellow Line trains at Mount Vernon Square at all hours, Metro began running off-peak Yellow Line trains all the way to Fort Totten in December 2006. The service started as a pilot program, but was quickly made permanent due to high demand.

However, there are three major obstacles preventing Yellow Line trains from running to Fort Totten during peak hours: there's no a pocket track at Fort Totten, Metro only has so many trains, and Metro doesn't have the money (Matt explored these factors in depth in his 2010 post).

An above-ground pocket track north of Silver Spring. Image via Wikimedia Commons.

Turning some trains around at pocket tracks (like the one at Mount Vernon Square) rather than running them all the way to the end of the line allows more trains to run on the given section of the Metro system because it keeps terminal stations like Greenbelt from getting overwhelmed.

For example, 50% of rush hour Red Line trains only run between Grosvenor-Strathmore and Silver Spring (rather than all the way from Shady Grove to Glenmont), using the pocket tracks at these stations to reverse and head back in the other direction. This means that Shady Grove and Glenmont only have to handle turning around 13 trains per hour, rather than the maximum of 26.

There is excess rush hour capacity on the Green/Yellow Line tracks north of Mount Vernon Square, as you can see in Matt Johnson's graphic below, and extending the Yellow Line to Fort Totten would take advantage of it (as the four hourly Rush+ Yellow Line trains to Greenbelt already do).

Metro service vs. capacity. Graphic by Matt Johnson.

But without building a pocket track somewhere between Mount Vernon Square and Greenbelt (such as at Fort Totten), it is impossible to take full advantage of this capacity without overwhelming operations at the busy Green Line terminal. Unfortunately, there are significant obstacles standing in the way of this.

In addition to the cost of the pocket track itself, Metro would have to pay for additional rolling stock in order to operate the extended Yellow Line service full time. As Matt explains, the increased service would require 30 additional railcars at a cost of approximately $100 million, plus $3 million per year in operating costs. The new railcars would have to come from Metro's order for the 8000 series, which aren't expected to begin delivery until at least 2023.

Is it possible to build an extra pocket track between Mount Vernon Square and Greenbelt? And how come one didn't go in in the first place? I'll take a look at that in a post next week.

Correction: This post initially said there are crossovers at every station between Gallery Place and Fort Totten. That isn't the case, and given where the crossovers are, U Street makes sense for the current Yellow Line issue.


Three ways Metro's loop proposal could get better

Metro's proposed loop has generated much discussion about the future of the transit system. While new capacity is an important goal, it's not the only goal. Metro should also try to avoid designing in problems. A few tweaks could greatly improve the proposal.

Gallery Place crowding. Photo by the author.

One of the challenges of adding in a new crosstown line where one was never envisioned is dealing with transfers.

It's absolutely essential that Metro get these transfer stations right. Today, Gallery Place is a nightmare due to its flawed design. That station was designed with two major flaws. The off-center meeting of the Green and Red Lines is due to the Red Line swinging south to Judiciary Square. The narrow platforms are because of the historic art museum upstairs. We're still paying for a design decision made 40 years ago, and it really illustrates the need to get it right this time.

Metro's loop proposal is still very nebulous because it's so early in planning. Much could change. But the conceptual alignments shown in their map suggest the potential for inefficient transfer stations.

Building better transfer stations

At Waterfront, for example, the Green Line follows M Street. The proposed loop would run under Eye Street, 3 blocks north. Right now, riders from Alexandria and South Arlington have a straight shot on the Yellow Line to the 7th Street subway and the eastern side of downtown.

See the Waterfront station under: Eye Street M Street. All graphics by the author.

If the new loop station is built at 4th and Eye, those riders will have to walk over 1,000 feet to change from the Yellow to the Green. That's as long as the walk from Metro Center to Gallery Place. The additional inconvenience and time it takes to transfer will make transit less competitive for many riders. And it may create future crowding issues, like those faced at Gallery Place.

Locating the new station adjacent to the existing Waterfront stop would make transferring much easier and less time-consuming. And that would be a boon for many riders, especially those who would need to transfer under the new scheme, like anyone who takes the current Yellow Line from Virginia to downtown DC.

There's an even better solution than just building the new station next to the old one: Build a new station for the Green Line and the loop line.

A four-track design like the one above would make transferring very easy. Many riders wouldn't even need to use an escalator. Inbound trains would be on one level and outbound trains would be on another. This is exactly like the design of the Lionel-Groulx transfer station in Montreal.

This would probably not be possible as a reconstruction of the existing Waterfront station, but would probably need to be new construction adjacent to the current stop.

In this design, a commuter riding from Suitland to Union Station could simply exit her Green Line train at Waterfront and walk across the platform to board a Loop train on the outer loop headed toward Capitol South and Union Station.

Similarly, a person commuting from Huntington to Archives could get off his Yellow Line train at Waterfront and just walk right across the platform to a waiting Green Line train headed toward L'Enfant and Gallery Place.

Similar situations exist where the proposed loop line crosses the Red Line. Metro's proposal seems to keep the new line under H Street near Union Station and under M Street where it crosses Connecticut Avenue.

The Red Line is currently Metro's busiest line, and it provides access to many destinations. Forcing riders to make long walks is inefficient, and if the tunnels deposit riders at one end of the platform, a situation similar to the one at Gallery Place is likely to arise again.

The transfer at Farragut North/Longfellow isn't as bad as the potential one at Waterfront. But the walk between the stops would still be almost 750 feet. Instead of keeping the line under M Street, the loop could swing down Vermont Avenue to either K or L Street. That would allow a much shorter transfer between the Red Line and the Orange Line as well.

See the Farragut station under: M Street K Street

At Union Station, Amtrak has grand plans to expand the station and create a second front along H Street on the north side of the complex. In that regard, Metro's loop wouldn't be too inconvenient to commuter and Amtrak trains. Of course, if the redevelopment of the station doesn't happen, riders would have a less pleasant trek to connect to their trains.

But the walk to connect to the congested north end of the Red Line platform is over 600 feet. And that means that riders connecting to trains bound for Metro Center or Silver Spring would also have an inconvenient transfer.

Locating the new loop station on the south side of the station, under Massachusetts Avenue, could make transfers much easier, and it wouldn't sacrifice access to commuter or Amtrak trains either.

See the Union Station station under: H Street Massachusetts Avenue

The Massachusetts Avenue alternative also seems to make it easier to extend the M Street subway east across Capitol Hill and/or the 2nd Street subway up North Capitol Street should future demand warrant that expansion. Ideally, the station under Massachusetts Avenue would include 4 tracks and 2 platforms so that if the loop were split into an east-west and a north-south line trains wouldn't have to share tracks.


One of the bigger tradeoffs is the discussion of whether increasing the area within a 5 or 10 minute walk of transit is more important than easy transfers.

For example, if the new loop line is pulled down to K Street at Farragut Square, the West End station would be farther south, closer to the existing Foggy Bottom station. That means that less new territory would be within a 5 minute walk of Metro. On the other hand, essentially all of the West End is already within a 10 minute walk of Metro.

Compare some alternatives below. Note that the tan and gray areas are within 10 and 5 minute walks of existing stations. Light pink areas would be new areas within 10 minutes of Metro and dark pink areas would be new areas within 5 minutes of Metro.

Walksheds from existing stations.

Walksheds from Metro's loop proposal.

Walksheds from a K Street/Mass Ave alternative.

Better transfer stations could mean fewer headaches for future commuters. But it might also mean less area is available for new development in the core, lowering tax revenues for the District. Co-locating stations is also likely to be more expensive and disruptive to riders. But in many cases, it may well be worth it. It's certainly worth having the discussion.


How would Metro's loop work with an Arlington express line?

Last week, we discussed Metro's proposed new downtown loop line in terms of the Blue and Yellow lines. Metro also plans to feed the loop with a new "express" line along I-66 in Arlington.

While Metro's plans are still in the early stages, at the moment, they seem to be focusing on a new line that would follow I-66 between East Falls Church and Rosslyn, bypassing the crowded Rosslyn-Ballston corridor.

All graphics by the author.

Metro's 2040 projections indicate the need for a new line in Northern Virginia. They estimate that by 2040, there will be significant crowding aboard inbound Silver Line trains before they even get to Tysons, but sharing track with the Orange Line constrains its capacity. They also estimate that by 2040, passengers in the Rosslyn-Ballston Corridor will find it difficult to board trains, with crowding conditions beyond what is considered acceptable today.

The new express corridor would run alongside the Orange Line in the median of I-66 from the junction with the Dulles Airport Access Road until the Orange Line splits off to follow Fairfax Drive. The new line would stay in the median of I-66 to bypass the Rosslyn-Ballston corridor.

The new line would allow up to 26 trains per hour (TPH) to run on the Silver Line as well as on the Orange Line, for a total of 52 TPH passing through East Falls Church. It would feed the proposed downtown Metro loop, along with the Blue and Yellow Lines.

The map above shows one way the new line could operate. Under this scenario, the Silver Line would have a companion, which I'm dubbing the Gold Line for the purposes of this discussion.

The downtown loop would have a capacity of 26 TPH in each direction. The Blue and Yellow lines would use 13 TPH of that capacity in each direction, leaving 13 TPH available on the inner loop and 13 TPH available on the outer loop. For this reason, half of the trains on what I'm calling the North Arlington Express line would need to run counterclockwise and half would need to run clockwise, at least to use the loop to its full capacity.

To avoid confusion, it is likely that Metro would use two different colors for the express line. In the scenario outlined in the map above, half of the trains coming from Dulles would be colored Silver, while the other half would be Gold. Each would alternate, going around the loop in the opposite direction.

Of course, it would also be possible to "transform" the lines as I described with regard to the Blue and Yellow lines on the loop in the last post. That way, riders would be used to taking the same color in the morning as the evening. But I did not illustrate that in a map, because with four lines on the loop, it becomes increasingly complex to show the transforms.

Running trains from the North Arlington Express onto the loop would maximize the capacity of the Dulles/Tysons line, the Orange Line, and the loop line at 26 TPH each.

Metro is not wedded to running the line down I-66. As planning continues, WMATA will do studies to determine the best location for the new line. It could be along I-66, or it could follow another corridor, but the concept is the same. By separating the Silver and Orange lines, WMATA can increase capacity to match the expected demand in northern Virginia.


How might the new Metro loop work?

Last week, WMATA planners released a proposal for a new Metro loop downtown to help relieve capacity issues on the other lines. How might this new line operate? Details are scarce, but we can talk about some possibilities.

Map from WMATA.

The proposal is to build a new Metro line that would loop through downtown DC. Starting at Rosslyn, the tracks would tunnel under the Potomac to Georgetown. They would then follow M Street and New Jersey Avenue to Union Station. The tracks would turn south along 2nd Street to cross Capitol Hill, and then parallel the Green Line under I Street. The loop would complete itself by joining to the existing Yellow Line bridge over the Potomac River.

Metro's proposal indicates that the loop line will be fed by the current Blue and Yellow lines, which would enter at the Pentagon station, and a new "express" line in northern Arlington, which would enter near Rosslyn.

Why build a loop?

Metro's team of planners looked at a variety of solutions to the core capacity issues, including new lines. The alternative they settled on was this loop. Why did they pick a loop?

Essentially, a loop solves most of Metro's problems relatively cheaply. The primary issue facing Metro over the next few decades is core capacity, espcially in terms of train throughput. The Blue/Orange subway through downtown is at capacity, and no more trains can be added.

Untangling the Gordian knot at Rosslyn is the most complicated part of this. What is most clear is that Metro needs a new Potomac crossing near Rosslyn to increase capacity on the Blue, Orange, and Silver lines.

But Metro also needs more capacity around the southern side of downtown DC. Because the Green and Yellow Lines share the 7th Street subway, which is operating very close to capacity, each line can only be increased at the expense of the other line. In other words, WMATA can't add Green trains without subtracting Yellow trains. So Metro also needs a new subway for the Yellow Line.

However, Metro's studies found little need for a new subways outside of downtown based on the expected travel patterns in and density of those areas in 2040.

Essentially, Metro sees the need to build an east-west subway across the north side of downtown and a north-south subway across the east side of downtown. But they don't see a need for the east-west subway to continue east or the north-south subway to continue north.

For that reason, Metro thinks it makes the most sense to just connect the east-west and north-south subways at Union Station and operate them as a loop.

Operating patterns

It's not exactly clear how the new subway loop would work, and since this project is decades away from completion much could change. But there are a few likely ways it could operate.

For now, let's only consider the Blue and Yellow Lines. We will discuss the proposed North Arlington Express line in a later post.

Operating an inner and outer loop is one of the obvious choices. In this scenario, one of the lines would run clockwise around the inner loop, while the other line runs counterclockwise around the outer loop.

Scenario 1. All maps by the author unless noted.

So Yellow Line trains coming from Huntington would cross the Potomac north of the Pentagon, as they do today. Then they would continue east to Capitol Hill before turning north toward Union Station and going around the loop to return to Huntington via Arlington Cemetery. Blue Line trains would do the reverse.

One of the advantages of operating the Yellow and Blue lines as a loop through downtown is that the loop can actually carry more capacity. If the Blue and Yellow didn't need to share tracks with the Orange and Green lines, each could run at a frequency of 13 trains per hour (TPH) in each direction. And that means that the outer loop would have 13 TPH, as would the inner loop. Since Metro's track capacity is 26 TPH, there's actually room to add two more lines to the loop.

One of the disadvantages, though, is that riders who have a short one-seat ride in the morning have a long one-seat ride in the afternoon. Someone who commutes from Franconia to Georgetown has a pretty direct trip in the morning. But in the afternoon, they either have to face a long ride on the Blue Line via Union Station and Potomac Park or take a two-seat ride by riding the Yellow Line to Pentagon and changing.

"Transforming" loop trains would resolve that problem, though it would be more complicated and difficult to show on the map.

Scenario 2.

In this scenario, a Blue Line train leaving Franconia would run as far as Pentagon and then continue toward Arlington Cemetery. At some point on its journey, the train would magically transform into a Yellow Line train bound for Huntington. Yellow Line trains would operate similarly, becoming Blue Line trains during their journeys.

This way, a person who commutes from Franconia to Georgetown would have a short, one-seat ride on the Blue Line in both directions. The same would be the case for Yellow Line riders.

For anyone waiting for trains at a station on the loop, trains on the outer loop would always be bound for Franconia, but would have come from Huntington. On the inner loop, trains would be bound for Huntington, but would have come from Franconia.

To avoid confusion, trains bound for the loop would just be signed with their color and a destination of "Downtown." The change of color and destination on the loop wouldn't matter for the passengers on board, since the train would continue around the loop. This is, incidentally, what Chicago L trains do as they arrive at the Loop: they change their headsigns from "Loop" to whichever destination they're headed back to.

Alternatively, trains don't have to "loop" all the way around the loop. Instead, the Blue and Yellow lines could just be interlined on the new tracks.

Scenario 3.

In this scenario, Blue Line trains would operate onto the new tracks for a certain distance. On the map above, I've shown trains going as far as 4th & Eye, but they could stop at any point along the line (Union Station, for example). Then trains turn back around and run over the same tracks back to Franconia. Yellow Line trains would operate similarly.

Anywhere the two lines overlap would max out the capacity of the new line, just as the other lines in the core are currently topped out at 26 TPH. The reason this is true for the interlined scenario but not for the loop scenarios is because in the loop scenarios, trains run around the loop once. In the interlined scenario trains run over the tracks twice, once inbound and once again outbound.

North Arlington Express trains

As noted above, the new loop would also carry trains from the North Arlington Express line. We haven't discussed those trains yet, but we're going to cover how they might work with the loop in another post soon.

Metro's vision for the future is still decades away, so we have no idea what the final product will look like exactly. It might look like one of the operating patterns shown here, but then again, lots can change in 25 years. But Metro's core is approaching capacity, and expansion is desperately needed. Metro's new vision will set the stage for building the system's next generation.


Metro maps out loop line between DC and Arlington

To relieve congestion on the Orange and Blue lines and support future growth in the region's core, Metro is proposing a loop line between downtown DC and Arlington. They've just created a map of what the service might look like.

Detail of Metro's proposed downtown loop from PlanItMetro.

The loop is part of Metro's Regional Transit System Plan, which lays out a vision of how the transit system should expand over the next three decades to accommodate predicted regional growth. It incorporates previously studied ways to expand Metro in downtown DC, including new Blue and Yellow lines.

The loop line would go to areas that don't have Metro service, like Georgetown, while adding new connections to existing transfer points like Farragut Square and Union Station. It's unclear how Metro's service patterns would change to serve the loop. Right now, the map shows the Blue, Orange, Silver, and Yellow lines all running on the loop.

WMATA planners are also considering an express line on I-66.

Metro's also looking at a new express line along I-66 between Rosslyn and East Falls Church, which could give the Silver Line an alternate, faster path to downtown DC. This isn't a new idea, either.

What do you think of Metro's loop line?


Metro beyond 2025, part 2: The Blue Line to Georgetown

Yesterday, we discussed how Metro could grow its core capacity if it chooses to build a Rosslyn wye in the short run. Today we'll look at how a terminal for the Blue Line could fit into the picture.

Photo by tracktwentynine on Flickr.

Today, Rosslyn is the biggest bottleneck in the system, which will only get worse when the Silver Line opens. Three lines vie for space in one tunnel from Rosslyn eastward, which limits trains on the Blue, Orange, and Silver Lines.

Metro could relieve the pressure for now by either building a new terminal for the Blue Line at Rosslyn, or a "wye" to let some trains from Tysons go to Arlington Cemetery and farther south in Virginia. But in the long run, Metro needs more capacity over the Potomac River.

Post-2025 solutions with a Rosslyn terminal

The Rosslyn terminal would enable Blue Line trains to terminate at Rosslyn without interfering with the Orange or Silver Lines. This would allow more Orange and Silver trains from Tysons and the Rosslyn-Ballston corridor. But it also means that all Blue Line riders going to DC would need to transfer at Rosslyn or Pentagon.

That solution might work for a few years, but if Metro ridership continues to grow, the Rosslyn terminal would need to become the first phase of a new Potomac crossing.

A separated Blue Line: Metro could easily expand a Rosslyn Terminal into a new line to DC. A likely path would take the line under the river to Georgetown and then east into the downtown core.

In addition to the 26 trains per hour (TPH) running between Rosslyn and Downtown on the Orange/Silver subway, an a separated Blue Line to Georgetown and into downtown would allow 12-16 additional trains to cross the Potomac at Rosslyn.

This would increase the number of trains running between Virginia and DC per hour during the peak from 40 to 52.

However, because the Blue Line shares with the Yellow Line, the new subway across downtown Washington would only be able to operate at roughly half of its maximum capacity. That's probably fine in terms of ridership for a while (and off-peak for much longer), but in order to get the full potential out of the new line, it would need to be separated from the Yellow Line.

A separated Blue Line could also allow for more service on the Green Line through the Waterfront or Capitol Riverfront areas, which are quickly adding jobs. Metro could get some additional Green capacity by shifting some Huntington trains to the new Blue subway via Rosslyn (a sort of reverse Rush Plus).

Shifting some Huntington trains to run through Rosslyn would not increase the number of trains crossing the Potomac beyond what could cross under the first separated Blue Line scenario, but it would enable more service on the Green Line.

Two new subways?

What about both a separated Blue Line and a separated Yellow Line? Two new subways in the core would be very expensive. But if Metro wants to maximize the capacity on its system, it has to separate each line in the core.

One way to do this is to build a new terminal for the Blue Line at Pentagon. The Blue Line could have its own platforms, and trains from Franconia-Springfield (now all colored Yellow, or perhaps a new color) and Huntington would all cross the 14th Street bridge.

This would also have the advantage of reducing the amount of interlining in the system. With the lines no longer sharing with each other, delays wouldn't cascade across multiple lines if a train were to break down or some other mishap were to occur.

But the real issue is being able to have the flexibility to balance trains across the different lines. Right now, the Blue and Orange must be balanced based on ridership demand, as do the Green and Yellow. The problem is that Metro is bumping up against the absolute capacity of both subways.

With just a separated Blue, there would still be demand for a direct trip across the 14th Street Bridge. And once that demand outstrips Metro's ability to provide supply, Metro won't be able to do anything (because the Yellow shares with the Green). With just a separated Yellow, service between Pentagon and the western side of downtown is constrained by demand for the Orange/Silver.

At some point in the future, if Metro keeps growing, it may become necessary to build the other separated line. With both a separated Blue and a separated Yellow, the number of trains crossing the Potomac would increase to a maximum of 78.

Other improvements would probably be necessary to enable a full 26 trains per hour to run on the Green Line. It's not clear if the terminals at the end of each line could handle turning 26 trains each hour. Metro would probably need places for trains to turn around short of the terminals, like the pocket tracks at Silver Spring and Grosvenor on the Red Line. Alternatively, Metro could look into rebuilding the terminals, Branch Avenue and Greenbelt, with more capacity.

It's hard enough to say if we can get one new subway by 2040, given the funding picture today. But a second new subway might be in the cards farther down the line, and now is the time to start planning for it.


Metro beyond 2025: Possible futures with new connections

Last week, we talked about plans to give Metro the capacity it needs to get through 2025. What about beyond? The primary issue after 2025 will be cross-Potomac capacity.

Photo by the author.

Metro will likely choose to build, hopefully by 2025, either a new terminal for the Blue Line at Rosslyn that doesn't share tracks with the Orange or Silver Lines, or a "wye" so trains from Vienna and Tysons can turn toward the Pentagon.

However, neither solution increases the number of trains that can cross the Potomac River. Metro will need to start planning for the next phase very soon, since it takes so long to plan and build transit. Also, Metro's plan beyond 2025 could influence which of the options (terminal or wye) it chooses for 2025. Let's look at how Metro might expand its core capacity starting with each of the 2 primary Rosslyn alternatives.

Post-2025 solutions that go with a Rosslyn wye

Without construction in the core, a Rosslyn wye alone can't add any cross-Potomac capacity. Metro could build a second wye at Pentagon, for trains from Vienna and Tysons to cross the 14th Street bridge. However, the 7th Street tunnel, which carries the Green and Yellow Lines through downtown, can't take any more trains.

Wyes at Pentagon and L'Enfant: If Metro builds a total of 3 wyes, at Rosslyn, Pentagon, and L'Enfant Plaza, it could fit a few more trains across the river. Trains from Arlington Cemetery could cross the 14th Street Bridge, then continue east onto the Green Line toward Branch Avenue.

This scenario would let Metro fill unused capacity in the system without building any new trunk lines. However, much of this new capacity would go on the Green Line south of Waterfront station. Customers wanting to get to the downtown area would have to transfer.

It would, however, significantly add service to the growing Waterfront and Capitol Riverfront areas. DC has zoned much of these areas for downtown densities, but instead of the 5 lines that serve downtown or 3 in the Golden Triangle, this area has just one. This option would beef up service there, though many of the people riding there would want to come from downtown, and this doesn't boost that connection.

To absolutely max out capacity, Metro would need to run a line, like the lime-colored line on the map above, from Franconia to Branch Avenue. It's not completely necessary, but it would allow more full use of the capacity.

Unfortunately, this would increase the amount of interlining in the system, because trains would be running across multiple lines. The complex scheduling it would take to run this sort of service pattern might actually lower the total number of trains Metro can run through a tunnel.

This scenario would increase trans-Potomac capacity from 40 to 52 trains per hour, or just to 46 TPH without the Franconia-Branch Avenue Line.

Pentagon wye and separate Yellow Line: Metro has talked about building a separate tunnel for the Yellow Line. It's not clear where it would go yet. It could run north along 9th or 10th Street, or it could run east toward Capitol Hill before turning north.

This subway would separate the Yellow and Green Lines. That would allow Metro to run additional Green Line service between Greenbelt and Branch Avenue, including more service between downtown and the Waterfront/Riverfront areas.

It would also allow more service across the Potomac by decoupling the Green and Yellow Lines. However, since the Yellow Line shares tracks with the Blue south of Pentagon, this new subway would not be used to its full capacity.

Metro could get some additional capacity by routing some trains from Tysons via Arlington Cemetery over the 14th Street Bridge and into the new subway, if it built a wye at Pentagon. This would increase service across the Potomac to 52 TPH. Without the line running from Tysons through Arlington Cemetery, that would drop to 46 TPH.

Splitting Yellow Line service: Another option Metro studied for the Yellow Line is a new tunnel through the Capitol Riverfront, past the Capitol, and north to Union Station. This would increase service at Union Station, a major bottleneck, and give riders two ways to get downtown from the Waterfront/Riverfront area.

However, a lot of the riders in Alexandria and southern Arlington don't want their train to go so far east. They want to get to the 7th Street corridor. Therefore, Metro studied the idea of splitting the Yellow Line, with some trains taking their current path through L'Enfant Plaza and Archives while others would go to Union Station.

This operating plan makes a lot of sense with the Rosslyn wye, because those trains can fill the "gap" left on the 14th Street Bridge by Blue Line trains running north toward Rosslyn. With a new path for some Yellow trains, there would be room to add more Green Line service.

This approach would allow 52 trains per hour to cross the Potomac.

Tomorrow, we'll look at another set of long-term solutions, which Metro might pursue if it builds a new Blue Line terminal and then can send the Blue Line across the river toward Georgetown.


WMATA wants longer trains, more tunnels, better service

WMATA hopes to lengthen all its trains to 8 cars, add pedestrian connections at downtown stations, and maybe build new rail tunnels for the Blue and Yellow Lines in the region's core. That's part of a strategic plan which its media relations team showed only to the Washington Post this week, and which board members will see at a meeting today.

The potential for new downtown tunnels (left) and connections between existing lines (right).

More broadly, the agency will focus on safety, service quality, better regional mobility, and its own financial stability in the strategic plan. Besides a set of still somewhat amorphous connections and service improvements, the plan calls for building a system where riders can more easily "plan, pay, and ride" in a smoother customer experience.

The big money, up to $20 billion, in the plan would be for tunnels to separate the Blue Line at Rosslyn and the Yellow Line at L'Enfant Plaza, the two major chokepoints, as part of a vision for Metro by 2040. Silver Line trains from Dulles Airport could also turn at Rosslyn to go toward Arlington Cemetery, then stop at Pentagon before crossing the Yellow Line bridge into DC.

Map by the author, from 2009.

By 2025, Metro wants to have the railcars and power stations to run all trains with the full 8 cars. It would like to build pedestrian tunnels to link Farragut North with West and Metro Center with Gallery Place, and a train tunnel so that some Dulles trains can go down to Franconia-Springfield, which would relieve some of the immediate Blue Line problems of Rush Plus, which will only get worse once the Silver Line opens.

Potential connections between existing lines (left) and stations (right).

WMATA Media Relations team makes transit supporters' task harder

This plan covers a lot of ground, and is at times very detailed yet at others quite vague. I wasn't able to get all of the details, because WMATA decided to give an exclusive look at the plan to the Washington Post.

This has been the agency's practice every since Barbara Richardson, Lyn Bowersox, and Dan Stessel took over at WMATA communications and media relations. This isn't a matter of blogs versus traditional media, though that's been an ongoing problem as well; WMATA also does not tell the Washington Examiner about its major initiatives.

This seems inappropriate, and really disrespects the journalists and bloggers who care about transit in the region. It's also pretty foolish, because it forces others to write about the plan in a more hurried way than they otherwise would.

WMATA planning head Shyam Kannan spent an hour talking to me after midnight last night, and this post was still not done by 4:30 am as a result. Still, there are plenty of questions I did not have time get answered.

What will happen with Union Station and commuter rail?

While the plan goes into a fair amount of detail about how there could be a second Pentagon station for the trains making the new track connection, the plan does not talk about whether the new lines would serve Union Station, the system's biggest point of overcrowding. It seems obvious for any separated Blue Line to go there.

One of the biggest opportunities to improve regional travel would be to let MARC trains reach L'Enfant Plaza, where riders can transfer to all four lines that don't serve Union Station, and onward to Virginia. Unfortunately, perhaps bowing to political realities, the plan just calls for WMATA to play a role of supporter and advocate.

Finally, the plan shows some diagrams with vague arrows depicting potential extensions to the ends of lines, regional transit in the suburbs, and streetcars crossing the river:

Vague arrows showing possible line extensions (left) and surface transit connections (right).

All of these ideas and more were part of a study WMATA has been working on for a few years, called the Regional Transit System Plan. That also included proposals to send the Yellow Line through the rapidly-growing Capitol Riverfront and up to Union Station.

According to Kannan, the RTSP study is still going on, and even many decisions about which routes WMATA wants to pursue in the future are not fully set.

Customer service, trip planning are even more central to the plan

Kannan emphasized that the rail expansions and connections are not the "real meat" of the plan, despite what was in the Post article; instead, it really focuses on "an improved customer service experience today" that will let riders plan, pay, and take transit more smoothly than today. The vision for 2025, which is not far away, is fundamentally about "the completion of a journey to a self-service system. He explained:

Imagine, for a moment, walking into a Metrorail station or a Metrobus platform and not needing to ask for assistance in either route planning, fare payment, and even walking to or from your bus or train. There would be improved lighting so you can read your book, mobile payment options so you can use your smartphone to pay your fare.
With these added services, Kannan said, station agents will not need to sit in their booths all day to handle everyday needs. Instead, Metro could dedicate its staff to "customer-facing ambassadors" who could roam around and help people, and choose people for those jobs best suited to a customer service role, which as we all know is not always the case with today's station agents.

Another big element of this self-service world is better trip planning. Kannan talked about having a "unified regional trip planning technology" so a rider can use a desktop computer, smartphone, or other device, pick where he or she wants to go, and get transit suggestions that could use Metro, commuter rail like VRE or MARC, or regional buses like Ride On and DASH.

The plan describes that as "Provide transit riders with a regional trip planning system that is mobile-device friendly." Hopefully this language does not lead the agency to decide it should issue a procurement for a big IT project to build one single integrated trip planner that works on today's mobile devices, and that's all. WMATA is not in a position to be a good customer-facing software company, and a big contracted software project will build something that will likely be obsolete as soon as it launches.

Rather, the agency needs to offer open data and support open source projects to create the building blocks of trip planning. VDOT funded a grant, which I wrote for Arlington County, to make progress on some open source technology for trip planning. If WMATA can support the efforts of the people who are going to do this work, and other developers who contribute and create other tools of their own, it will do far more to "provide" this kind of "unified regional trip planning technology."

The plan is not very detailed about how to reach this or most other goals, from "Educate the customer about transit coverage and usage in regional emergencies" to "Work with partners to ensure seamless connections between Metro and other transit systems in the region." Those are fodder for future plans. Meanwhile, though, if top management buys in and directs the organization to follow this plan, it can get the 13,000-person organization moving all together in some important directions.

The WMATA board will discuss the document at a meeting today. As usual with WMATA's process, since staff don't release anything until the very last minute before a board meeting, that means board members won't have the opportunity to hear any considered feedback from riders, to the extent they are interested in riders' views, as some are, while others are not.

Matt Johnson and I have also been working on some posts about the core capacity Metrorail proposals, and will try to better illuminate what kinds of tradeoffs Metro faces as it tries to deal with its bottlenecks and overcrowded segments.


Metro planners contemplate system's second generation

By 2040, Metrorail ridership is expected to top 1 million daily rides and the system's core will be severely crowded. To cope, Metro has been looking at long-term possibilities for expanding transit, whether on the Metro system itself or in other modes, like streetcars or BRT.

Photo by sabine01 on Flickr.

A "second generation" of the system might bring new lines to the region and extensions of lines beyond their current terminals. None of the plans are concrete right now, but the first step toward system expansion involves studying of multiple possible concepts and determining which make sense.

These projects are still very much in the planning phase. At this point, for Metro planners, it's mostly about modeling ridership and attempting to find ways to optimize operations and redundancy in the system.

If this second generation system is constructed, only some of the lines and extensions up for consideration today will become a reality. And, before the work is complete, they may look significantly different than they do at this early stage. However, while changes to the current proposals are to be expected, these suggestions are noteworthy, nonetheless, as one or more of these scenarios likely represents the future of Metro.

Separated Yellow Line: As we've discussed before, Metro is looking at ways to separate the Yellow and Green lines. Mainly, this will allow for capacity increases on the Green Line, since the Yellow will still have to share with the Blue Line.

One concept involves building a new line under 10th Street SW/NW parallel to the existing Green/Yellow subway. This line would likely end near Thomas Circle. An alternative would take the line further east, crossing the Blue/Orange subway at Capitol South and ending at Union Station.

Potential separated Yellow Line alignments. Click to enlarge (PDF).

Separated Blue Line:
This idea is not a new concept. Metro has been talking about it for several years. It would greatly expand core capacity, especially on the Orange Line. Additionally, it would open up new areas of the core, such as Georgetown and Logan Circle, to rail service.

With regard to a separated Blue Line, Metro has looked at 2 basic concepts. Both would involve a new separated Blue Line from Rosslyn to the Anacostia River.

One option would be a subway roughly following M Street. From Rosslyn, it would cross the Potomac River to Georgetown, and then proceed east, toward Thomas Circle, Mount Vernon Square, and Union Station. It would rejoin the current Blue/Orange rail line at River Terrace, where the existing Blue and Orange lines diverge.

First potential separated Blue Line alignment. Click to enlarge (PDF).

An alternative vision also takes the Blue Line from Rosslyn to Georgetown, as described above. Then the line would turn south toward the State Department. It would run through Federal Triangle and Archives before curving north toward Union Station. It would then head east to rejoin the Blue/Orange lines at River Terrace.

Second potential separated Blue Line alignment. Click to enlarge (PDF).

Separated Silver Line: This option would shave a few minutes off of trips from Downtown to Tysons Corner and Dulles, but it would not add much capacity to the system. Instead of a new Blue Line subway along M Street, that line would be given over to Silver Line trains. Blue and Orange Line trains would continue to share tracks in DC.

The Silver Line would also get its own tracks in much of Arlington. After Rosslyn, the line would run "express" along I-66, with East Falls Church as its first stop after Rosslyn. It would share tracks with the Orange Line along I-66 before diverging to head out along the Dulles Toll Road toward Tysons.

Separated Silver Line. Click to enlarge (PDF).

"Brown" Line: The study is considering some completely new lines, as well. One, dubbed the "Brown Line," would start at Friendship Heights and run down Wisconsin Avenue to Georgetown. It would then turn southeast, passing the State Department, before heading east toward Federal Triangle and Archives. It would stop at Union Station and continue north toward the Washington Hospital Center, Petworth, and Silver Spring. North of Silver Spring, the line would follow US-29 to White Oak and the Cherry Hill Employment District.

"Brown Line." Click to enlarge (PDF).

Beltway Line: Another possibility is a heavy rail line circumnavigating the region. It would mostly follow the Beltway, but would deviate from that alignment to serve areas like Wheaton and National Harbor.

It would not replace the Purple Line light rail currently in the design phase. In the northern suburbs, the Beltway Line would be north of the Purple Line alignment, intersecting the existing rail lines at New Carrollton, Greenbelt, Wheaton, and Grosvenor.

Beltway line. Click to enlarge (PDF).

National Harbor spur:
Metro is also considering building a spur off of the Green Line, connecting Congress Heights to the National Harbor development on the Potomac River. This line would primarily follow MLK Avenue. Since it would be sharing the Green Line, it would constrain headways on both branches south of Anacostia.

Possible National Harbor spur and extensions. Click to enlarge (PDF).

Extensions: The planning group is also looking at extensions to some of the existing lines. Elected officials in outer areas and people on our "fantasy map" discussions have often suggested them.

Without additional core capacity, though, these additions will only further burden the system. Although not all of these extensions will be built, Metro is looking at a variety of options for modeling purposes. They're considering how many new trips are generated, as well as how these extensions affect crowding in the core.

Potential extensions include:

  • Red Line: Western extension from Shady Grove to Metropolitan Grove
  • Green Line: Northern extension from Greenbelt to BWI Airport
  • Orange Line: Eastern extension from New Carrollton to Bowie
  • Blue Line: Eastern extension from Largo to Bowie
  • Green Line: Southern extension from Branch Avenue to Waldorf
  • Yellow Line: Southern extension from Huntington to Lorton, via US 1
  • Blue Line: Southern extension from Franconia to Dale City
  • Orange Line: Western extension from Vienna to Gainesville
  • Silver Line: Western extension from Route 772 to Leesburg
None of these are about to be built or even necessarily things Metro believes are good ideas. The study is simply evaluating options with an open mind. They generated some projections around ridership, which we'll look at in more detail, and are also studying light rail and BRT options alongside or instead of Metrorail.


Metro ponders new tunnels and connections

Before long, the Metro system will be bursting at the seams, besides those spots where trains are already stuffed to the gills. What can we do?

Photo by ep_jhu on Flickr.

To figure out some solutions, Metro's planning department has been analyzing many different alternatives for fixing the capacity bottlenecks. They've been posting the presentations to their Technical Advisory Group on PlanItMetro, allowing us to get a look at some of the possibilities even before they're fully analyzed.

To start with, Metro definitely needs to upgrade power systems to accommodate more 8-car trains, and build enough railcars to make up those trains. Other key capacity fixes that have been talked about for years include pedestrian walkways between Farragut North and West, and between Metro Center and Gallery Place.

Even with all of this and the "Yellow and Orange Line Service Increase" plan, trains will have 22% more demand than capacity by 2040, particularly on the Orange Line between Court House and Rosslyn, Yellow between Pentagon and L'Enfant Plaza, and Green between Congress Heights and L'Enfant, especially the segments around Waterfront and Navy Yard.

In the past, we've discussed some of the possibilities. One long-discussed option is to separate the Blue Line into a new tunnel of its own through Georgetown, the Mount Vernon Triangle, and H Street.

Left: Possible separate Blue Line. Right: Possible separate Yellow Line.
Click on an image to enlarge.

Another would be to build a separate tunnel for the Yellow Line next to the current Yellow and Green tunnel between L'Enfant and Mt. Vernon Square. This would allow more Yellow and Green trains since ethey would no longer have to share tracks.

However, it would cost a lot of money yet not provide access to any new areas or deal with the growing transit demand as Southwest and Near Southeast become dense residential and job centers. Nor would it do anything about the heavy demand at Union Station, which will only increase as MARC and VRE add capacity.

Another option would be to route the new tunnel through SW and SE, along I Street SW/SE, then turning north past the Capitol to Union Station. Some trains over the bridge could take this route, while others could take the current route. Already, Metro plans to make some of the trains from Franconia-Springfield go over the bridge, so the Franconia trains could be the ones to take the 7th Street route while the Huntington trains went to Union Station, for example:

Click to enlarge.

One drawback of this option is that this new tunnel will not carry the maximum frequency of trains. That's because there's a limit to the number of trains through the King Street-Pentagon route, some of which would go to Rosslyn, some to L'Enfant, and the rest in the new tunnel.

The study estimates 6-minute headways during peak and 12-minute off-peak. By comparison, the Red Line has 2.5-minute headways peak and 6-minute off-peak.

In general, this is a drawback of the way the system was originally designed where different lines (except Red) share tracks. Many links don't get the maximum possible number of trains. To fix that, Metro could separate more lines with new tunnels. Or, they could add more switches so that different routes could use the available capacity:

Click to enlarge.

This option adds four track connections. Three, between Waterfront and the 14th Street bridge, between the bridge and Arlington Cemetery, and between the cemetery and Court House, would enable a new service between Branch Avenue and Dulles Airport.

A fourth lets trains on the Dulles line turn toward Vienna to maximize trains on both of the northern Fairfax branches. New stations connected to West Falls Church and Pentagon for the new lines would also accommodate transfers.

This option gives Virginia a lot more service and the whole system more flexibility to route around problems. On the other hand, it's likely to lead to more people transferring at more stations, and creates more crowding at Rosslyn since many trains will now bypass it. (Or can Rosslyn get another station like Pentagon does in this option?)

The clear question with all of these is whether Metrorail expansion is even right to consider, or whether money is better spent on light rail and bus service. Dan from BeyondDC always argues that for the cost of one heavy rail line, you can get streetcars and light rail all over the place.

Metro planners also took a look at many of these options, some of which are in the presentation already online while others will come up in future phases of this plan. Stay tuned for more great nuggets of information as the study progresses.

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