Dr. Gridlock

Feb 24, 2014

The Washington Post's Dr. Gridlock, Robert Thomson, will be online to take all your questions about Metro, traffic throughout the region and other transportation issues.

Can you explain the phenomenon behind the hurricane-force winds I often experience when entering or exiting underground metro stations?

I think you're feeling what engineers call the "piston effect" of the trains moving through the tunnels. In those confined spaces, the trains push air ahead of them and pull it in from behind.

Ventilaton shafts along the tunnels reduce the effect, but it's still easy enough to notice. I think it's stronger at some stations than others, or perhaps it's just the time of day or weather conditions. I've noticed it especially, for example, at the entrance to Eastern Market station. It might be stronger at stations with only one entrance/exit, or where that entrance/exit has a fairly direct line toward the tunnel.

The piston effect influences the temperature in the station.

I'm traveling from Northern Va into to Takoma Park Md weekdays and need to arrive by 10am. When is the best start time to avoid the worst delays?

Depends a great deal on your starting point in Northern Virginia. Generally speaking, your worst travel days are going to be Tuesdays through Thursdays. Travel on the Capital Beltway is easier near the Wilson Bridge than near the Legion Bridge.

The 14th Street Bridge is the worst of the lot.

But on any day, for a trip like that, you're going to need to build in buffer time -- extra time to allow unexpected delays.

Currnetly, the Orange Line trains eastbound during AM rush seem to get backed up often between Courthouse and Rosslyn in competition with the Blue Line trains approaching Rosslyn. Has Metro addressed the likelihood of additional backups approaching East Falls Church when the Silver Line opens?

I think it could be possible for backups to occur on either the Silver or Orange lines near where the Silver Line will join the Orange Line tracks. Silver Line trains are scheduled to operate every six minutes at rush hours.

One thing that will reduce the likelihood of that happening: There will be fewer trains on the Orange Line between Vienna and East Falls Church. When the Silver Line starts, Metro will eliminate the Rush Plus Orange Line trains. That'st to keep the number of trains entering the tunnel at Rosslyn to 26 per hour, which is the max Metro says the tunnel can accommodate.

Does OPM coordinate with local highway departments before making the decision to open/close the government? I assume they do, but recently I've seen OPM keep the government open only to have major roads (BW Parkway & Beltway) closed due to accidents and poor road conditions. Additionally, a two hour delay seems meaningless. The worker who would normally travel at 8:00 am is being told the roads won't be safe until 10:00, but the 6:00 am traveler is told the raods should be fine at 8:00. Which is it?

When severe weather is expected, OPM typically engages in a huge overnight conference call with the highway departments, local governments, schools, Metro, weather service officials and other parties who either provide transportation services or have to deal with the consequences of bad weather and delays.

I once asked the OPM official in charge of making the open/close/delay call which scenarios are the most difficult. They're all difficult, he said.

I understand that. OPM often has to make its call based on weather that hasn't arrived yet. And it needs to make one decision based on a forecast that may vary greatly across the DC region.

When the decision is make, OPM can't anticipate that a particular road will be closed by crashes at a particular time.

Depending on how close to a Metrorail station your start and end places are, you may want to check out using rail instead of driving.

For sure. Note that it's going to mean a transfer at some point, since Takoma station is on the Red Line.

If the Silver Line is complete, why can't the testing be conducted by having real passengers using the trains?

At this point, I think they'd be more likely to use crash test dummies than humans.

This is still the phase when the airports authority is trying to determine whether the builder has met the goals of the construction contract. Once the airports authority says yes, then Metro decides whether to accept the line as its own. Then it should take about 90 days for Metro to do its own tests on the line before opening.

I'm not sure how much actual passengers add to the testing process. One thing: You could test how long the doors need to remain open at each station, or how passengers flow through the stations. But that's a lot of testers. I have a feeling we won't be able to judge those things till the line is open for business.


You mentioned on a recent chat that I-66 west in the morning is one of the "traffic mysteries" you're working on solving with the traffic analysts at INRIX. Could you also look into the actual data for other commutes from VA to DC in the morning? Every article I see talks about how congestion in the DC area has gone down over the last few years. My commute from Falls Church just inside the Beltway on Rt 50 to the Navy Yard area (usually via Wash Blvd and I-395) has done the opposite and now takes 30% longer than it did a year and a half ago. What do the data show?

Our folks are working with INRIX on a first round of "traffic mystery" questions that readers submitted. Let's see how that one comes out, before we start a second round. (The analysis is complicated, and we're going to try to address all the "mysteries" in the original round at once, rather than one by one.)

Metro Board Member and Mayoral Candidate Muriel Bowser has posted campaign ads on Metro buses. Isn't this a huge conflict of interest?

I don't see how Metro, or its advertising agency, could deny any candidate the right to buy campaign ads to post on buses, trains or in stations.

I haven't seen these ads and don't know what they say, but it strikes me that it's a little risky for a candidate to be identified with the bus service. A rider who may be having a bad day on the bus might choose to take that out on the candidate.

This also strikes me as interesting in light of the proposed fare increases that the Metro board will take up in March. Bowser has said at the Metro board meetings that she is reluctant to raise fares for bus riders. So in March, we may see a positive association between her candidacy and the bus ads, as far as bus riders are concerned.

Do you know who we can contact to report a stoplight that is out of synch with the other lights during rush hour? The recently installed light at Brentwood Road and Rhode Island Ave NE (right in front of the infamous non-responsive fire station) is not aligned with the other lights, causing backups and gridlock with Rhode Island Ave traffic backing into the intersection with 14th Street and Montana.

It's the same as for other city services: You call 311 to report the problem.

Dr. G - When is the escalator construction at L'Enfant going to be finished? The lower platform gets dangerously crowded at rush hour because there aren't enough escalators to handle all the passengers, and the blue boxes take up so much space on the platform. (Frankly, this is insult to injury - us Blue Line riders are told to take Yellow rush plus trains and transfer, and then the transfer process is utterly miserable.)

Looking at the list of Metro escalator outages, I see that five are out of service at L'Enfant Plaza station. (This is what strikes me when I look at Metro's quarterly reviews of service. The report will say that escalator availability averaged over 90 percent. But that won't match up with the experience of many riders. If you use L'Enfant Plaza today, you're very likely to encounter an out of service escalator.)

Three of the five are out for modernizations. One is due back in service this week, another in March and a third in April. One is turned off for use as a walker, something Metro does when a nearby escalator is being worked on.

The fifth is out for a service call and is scheduled to be back in service Wednesday.

Metro couldn't keep any particular candidate from advertising, but they could they ban equally ALL political or campaign advertising? Apart from the issue of selling space to their regulators, riders are a captive audience while they are on the train or bus. They can't change the channel or turn the page.

Many of you have seen the sorts of ads that a public agency like Metro is required to permit within the transit system. Some of them have been quite repulsive, but they are protected speech. I don't believe Metro would have any right to ban either one politician or a class of politicians from advertising.

Have you noticed that various stations on the Blue/Orange line have these very clear, brightly lit signs showing the set of stations that the Blue/Orange and Silver Lines stop at. Except that all of them show the Blue Line going straight from Foggy Bottom to Arlington Cemetery and not stopping at Rosslyn. How much money and time was wasted preparing these signs, and how could no one have noticed that such a simple set of signs had such an obvious error?It's not a big thing, but it's definitely symbolic of something.

Now, this I have not seen. I know that some incorrect signs were posted in January at Metro Center, but were taken down.

Where did you see your sign?

(There's no change in the plan. The Blue, Orange and Silver lines will stop at Rosslyn.)

Dr Gridlock, How would one request that the Circulator extend its night route to union station. With all the Condo's going up near Mount Vernon and the growth of population around Chinatown/ PQ I would think this area could now fully support the whole route for the full service. Currently the 9 PM cutoff time for any buses past McPherson Square limits its use. It would be great to be able to take it back from Georgetown on a weekend night.

You could make that request on Tuesday, when the DC Circulator officials are scheduled to hold one of their semi-annual meetings with riders. This one is scheduled for 6 to 8 p.m. Tuesday at the North Hall of Eastern Market, 225 Seventh St. SE.

I wonder if anyone has thought of the idea of building the Purple line as a metre-gauge railroad, with slightly narrower cars. Then there might be room for all those paths in Bethesda that people are want, and there would be more space for auto lanes on Wayne Avenue, and to pass through the Univ. of MD. "Normal" tracks are 4 ft, 8.5 inches wide, and this would change it to about 3 ft, 4 inches, but it could be enough to make more things feasible along the right-of-way. It's been done in Europe for over a century, and it just makes the system more versatile.

In all our discussions of the Purple Line, I don't recall getting down to the width of the light rail. Width consideration is certainly a legitimate concern, considering the traffic and trail impacts, but I don't know whether a narrow gauge would change the outcome.

When wet (or even just a bit damp) the floor tiles in metro stations are incredibly slippery. Do you know if Metro is aware of this problem or if they have any plans to address it? Putting up 'Wet Floor' signs is the best they've managed so far.

Metro has been aware of this problem for many years, though transit officials are more likely to refer to it delicately, as in: "The tiles have a poor coefficient of friction."

They hate those old tiles for many reasons. At outdoor stations, Metro is replacing the old tiles with a new style that has several advantages. They come in big panels that are easier to replace than the individual tiles. And they're much less slippery.

Hi Dr. Gridlock. Do you have any idea why all of the fare gates were closed at Rosslyn station this morning? Everyone entering in or out of the station went thorough the emergency gates, so no one swiped their smart trip card.

I don't know what caused that problem. From your description, it sounds like a power problem isolated to Rosslyn, but I'm not sure.


What do you think the potential of I-66 inside the beltway switching from an HOV to a HOT lane model?

I think you could see a HOT lane outside the Beltway but not inside.

Inside the Beltway, you have two lanes in each direction. I don't see VDOT or the feds approving the conversion of one lane out of two to high-occupancy toll. And I don't believe it's workable to have the entire highway converted to HOT.

Outside the Beltway, where you have at least three lanes each way, that's a different story. I think VDOT is interested in the idea of converting the HOV lanes to HOT lanes. That would be similar set up to the Beltway and I-95 HOT lanes: All-electronic tolling, drivers could carpool for free, with the proper E-ZPass, druvers who don't meet the HOV requirement would pay a variable toll.


last Monday was at Foggy Bottom and at Federal Center SW.

Thanks, I'll look for them -- if they haven't bee replaced already.

Dr. G., any idea why one of the Bethesda escalators from mezzanine to platform is being redone again? Is it repair or replacement? We endured a year (6 months for each escalator) of crowding and chaos not too long ago when these escalators were replaced. How can it require major shutdown so soon? It's a good thing stairs were added to the station, as that helps some. But the cutting in line and me-first attitude of ignoring the fact that both the stairs and escalator must have 2 way traffic is getting on my nerves. And Bethesda is supposed to be the model station of the future!

One escalator between the mezzanine and platform is undergoing a modernization and is scheduled to be back in service March 21. The other one is stopped so people can use it in both directions.

A "modernization" isn't exactly a repair and it isnt' a replacement. A repair typically occurs when the thing breaks down. A modernization is a scheduled upgrade of the equipment. Metro plans to replace a lot more of the escalators in the next few years, basically giving up on some of that old equipment that breaks down so frequently.

Like you, I remember that it wasn't very long ago that Metro did major work on those platform-mezzanine escalators. There were long lines of people to get on and off the platform every time a train arrived. (This was before the stairway was built.)

I'll check on why this modernization is underway now.


Have you thought about the Yellow line to Ft. Totten or Chinatown to the red line? From Huntington it should take 50 minutes and may be way less stressful than driving.

I don't ride Metro every day, but I often encounter stations where two escalators are running one way (usually the wrong way for the time of day) and the third isn't running at all. Last week I entered Metro Center at F street at about 11 p.m., and the only two operating escalators were both running up. I had a fairly animated conversation with the attendant (at least she wasn't asleep) who insisted that she had no control over the escalators, and that she had called a technician who had yet to appear. Can this be correct? The attendant can't reverse one escalator when another is shut down? Technicians aren't required to adjust the directions as needed? This just seems hard to believe, yet, knowing Metro, it's entirely believable. The attendants don't have access to the buttons? What do you know?

That doesn't sound exactly right. For example, I've seen station managers restart escalators after they were shutdown because a stroller or a walker banged against the steps.

Metro does have a general approach to the escalator directions, and we've talked about that here before: The bias is toward getting people out of the stations, so that the platforms don't become dangerously crowded. Nats fans may see that after the game at the Half Street entrance.

This annoys many riders, but the intention is safety.

I can imagine a station manager saying she has no control over Metro policy in the escalator's direction, or no ability to fix an escalator that is busted. But the station manager does have the ability to push the buttons.

A recent post mentioned tomorrow's Circulator Forum at Eastern Market. The post linked to a Transit Development Plan that while quite informative is three years old. Although disconnected from the Metro fare increase process, there has been talk of increasing Circulator fares effective July 1 to as much as $2 cash and $1.50 Smartrip. Part of the attraction of Circulator has to be the $1 fare (and only 50c w/rail transfer) making some SmarTrip rail+Circulator trip costs competitive with rail-only. Do you have insight into whether this increase is still being considered?

Here's a link to the posting I did about the Tuesday night forum on Circulator service.

Yes, Circulator fare increases are still under consideration. Circulator managers, like other transit managers, have to consider what they would call their "farebox recovery ratio." Or to put it another way, how much of a subsidy do the taxpayers need to contribute to maintain that number of buseson that route?

But there are other issues, too. After years of growth, Circulator ridership declined somewhat in the past several years, according to DC figures. (See the posting.) There's bound to be some shrinkage in ridership of the fare goes up.

And there's a political issue: DC is likely to resist the proposed increase in the Metrobus fare. Does it make political sense to oppose the Metrobus fare increase, and then say okay to a fare increase for the Circulator?


Thanks for joining me today. Stay safe out there and come back for our chat next Monday. We may have more news on the Silver Line schedule by then.

In This Chat
Robert Thomson
Robert Thomson is The Washington Post's Dr. Gridlock. He offers therapy for that most intimate relationship: the one between you and your commute. You can read his work on his namesake blog, as well as in the Metro section of The Washington Post.
Recent Chats
  • Next: