Dr. Gridlock Tackles Your Traffic and Transit Issues

Robert Thomson
Washington Post Columnist
Monday, July 20, 2009; 12:00 PM

Robert Thomson is The Washington Post's Dr. Gridlock. He was online Monday, July 20, at Noon ET to diagnose all of your traffic and transit issues.


Robert Thomson: Hello, travelers. No summertime lull in our mail today. Lots of good issues about traffic, transit, walking and biking. Early on, I'll try to post some on which I -- and the questioner -- could use your advice. Keep them coming.


Washington, D.C.: Hey, Dr. G - Ever since the Metro accident, I've noticed fewer 8-car trains on every line... mostly because trains are pulling up to the front end of the platform. Anyone else noticed the same thing?

Robert Thomson: Metro says there has been no cutback in eight-car trains since the June 22 crash. There wouldn't be any reason to cut back.

Certainly, it has become a lot easier to tell whether a six car or eight car train is arriving. If it's a six car, the people at the end of the platform are going to run forward, because all the trains are stopping at the front of the platform.

Do other riders think they're seeing fewer eight-car trains?

Do you have difficulties with the trains stopping at the front of the platforms?


Downtown Silver Spring: Who in Montgomery County government is responsible for deciding where stoplights and Walk/Don't Walk signs go where?

The crosswalk on East-West Highway at the Summit Hills apartments/Chevy Chase Crest condos is one that needs one badly. The high pedestrian volume crossing the road with bus stops on both sides mixed with the high amount of traffic and the long distance between lights makes for quite a long wait to cross sometimes. To make matters worse, the "Slow down" signs in the median often get run over several times a week.

The intersection would be perfect for a pedestrian-controlled stoplight that would turn red only when persons are crossing. Only problem is who would be in charge of getting it done (that is if Montgomery County has the money).

Robert Thomson: This is a very challenging area for pedestrians, and I completely understand why you would want some help there.

To ask about the possibility of installing a pedestrian signal on East-West Highway, write to the regional office of the Maryland State Highway Administration at 9300 Kenilworth Avenue, Greenbelt, MD 20770

Attention: Jeffrey Wentz, Assistant District Engineer of Traffic for Montgomery County

All across the region, there's a tension between the needs of pedestrians and the need to keep traffic flowing on major roads. Engineers would study the location -- if they haven't already -- and evaluate the safety issues, the location of other traffic signals nearby and the options for dealing with the issue.

They don't always go for a new signal. For example, they didn't put one at another crosswalk in Silver Spring on Colesville Road near the Silver Spring Library after evaluating the traffic issues and the proximity of the signalized intersection at Colesville and Spring Street.

I think there's an example of the type of signal you have in mind on New Hampshire Avenue at Quaint Acres Drive in Silver Spring. SHA felt a full red/yellow/green signal was not appropriate there, so it installed a signal that turns red only when activated.


Manassas, Va.: Hello Dr. Gridlock,

I've got a few rants. Maybe you could comment on them.

1st in Chantilly, the Willard Rd exit to get to the Capital Expo Center. What a disaster! You can take WestFields east or West to get there but there is NO SIGN telling you the shortest way to go (from 66 and Manassas). Not only that but if you take the exit from the airport, its difficult to make out how to go across because its not clear with all the barrels and such! Gad, how much longer is THAT going to last?!

2. Unairconditioned Orange Line cars! It was unbearable coming back from the Billy Joel Concert! It didn't matter how many people were in the car there was no air circulation until the doors opened and let some in.

3. Any shuttles being arranged for the Paul McCartney Concert at FEDEX?


Robert Thomson: Okay, here's one where I could use some further commentary from drivers on the Willard Road situation. Later this week, I'll try to get out there, too. But the first drive I need to take this afternoon is to further explore the new Beltway configuration at the Eisenhower Connector.

A crowded Metrorail car in the summer can be stifling. Sometimes, you'll see an empty car on a train that's been shut off because the air conditioning isn't working. If you are unlucky to find yourself on a malfunctioning car, so everyone a favor: Get the number of the car and report it to Metro, at 202-637-1328. Do yourself a favor and switch cars at the next station. The experience may be very different from car to car.

Paul is going to play FedEx on Saturday, Aug. 1, at 7:30. I think it's very unlikely there will be a shuttle bus service. The best transit option, in my opinion, is Metrorail to Morgan Boulevard and then follow the sidewalk north to FedEx. That's about a mile.


Silver Spring, Md.: Why is the Metro accident investigation taking so long?

Robert Thomson: It's very frustrating, isn't it? Wednesday is the one-month anniversary of the crash. Still, all Red Line riders are affected by the slow movement of trains through the crash zone between Takoma and Fort Totten.

That said, I'd really like the investigators to get this right. The track circuit in the crash zone continues to malfunction. They've got to figure out why. It's not only for the safety of riders between Takoma and Fort Totten. There may be some issue that could potentially affect other track circuits as well. They just don't know yet.

Also, on Saturday when the Red Line was shut between Silver Spring and Fort Totten, the investigators were doing something else very necessary: They were checking the sight lines in the crash zone, to see if that might have been a factor in the crash.


Gaithersburg, Md.: After reading about the ICC this weekend, I was wondering if the toll for the highway would include the portion of the road that goes from Sam Eig Highway to the Shady Grove metro. That would cause a terrible burden on metro riders. Thanks.

Robert Thomson: No, I'm pretty sure that stretch is outside the toll zone. The state wants to improve access to the Metro station without imposing a new burden on transit users.

I did a Commuter page feature in Sunday's Post describing progress on construction of the Intercounty Connector, which is now about a third done. The first part, the western part, is scheduled to open in fall 2010, and electronic tolling would start right away.


Wheaton: Dr G: How about a little palate cleanser question to take a break from Red Line woes? Here's something I've been wondering for a while.

Ever been in the elevator at the Wheaton station? There are more than buttons for street level and platform level. In fact, there are four other buttons, each with its own keyhole, I guess so someone authorized can access them. They are labeled, in order as you descend the depths that is Wheaton: SV, A1, A2 and A3.

What are these levels? What's in them? Dick Cheney's secret bunker? A portal to Narnia?

Robert Thomson: Most riders are going to say, circles of hell.


Ballston, Va.: Could the Tour D France wannabes in their lycra shorts and shaved legs please give it up riding double file down a hill at 25mph on road with a posted speed limit is stupid and dangerous and upsets those of us in cars who are stuck behind your Lance Armstrong wannabe bike. I realize you spent over $7k on your carbon fiber road bike from Trek but it still doesn't give you the right to obstruct traffic on winding two-lane roads, especially when you are climbing at less than 5mph. Go play somewhere else besides the back roads of Loudoun, PW, and Fauquier counties. Better yet take up mountain biking where you aren't endangering yourself and others and you can also wear baggy shorts. Real men mountain bike! I do.

Nothing worse than spending a Sunday morning worrying about these spandex-clad fools. And yeah I follow the rules of the road, laws etc. You roadies don't!

Robert Thomson: I think riding double is legal everywhere in our region -- if it doesn't impede traffic. Passing cyclists on winding, two-lane roads in the suburbs is difficult, so I understand drivers' frustration with this.


Rockville, Md.: Why can't metro get their Web site straight??

Right now (12:14pm), the lower left corner says "Red Line: On Time" but then to the right, the news has "Expect fewer trains, slower service to continue on Red Line"

Which is it - on time or fewer and slower??

If Metro people are reading this, I know of 5 people who work downtown, have been taking Metro for years, but are now driving and will not take Metro to work again.

Robert Thomson: If you changed your commuting habit following the crash, let me hear from you, both here on the chat and at drgridlock@washpost.com.

I also have noticed the mixed message you're referring to. On Metro's home page (www.wmata.com), the transit authority is doing a good job highlighting the Red Line troubles on its central display. Meanwhile, the Service Status indicator to the left of that display is showing the Red Line as "On Time." Given what Metro itself is saying about the state of the Red Line, that seems unrealistic, though as I recall, Metro's definition of "On Time" is a bit more flexible than the average commuter's.


Washington, D.C.: A comment. Dr. Gridlock you said:

"All across the region, there's a tension between the needs of pedestrians and the need to keep traffic flowing on major roads."

That is the understatement of the day. Why is it that we'll slow traffic for construction, emergency vehicles, the motorcade, schools buses, and ducklings but we are loathe to do it for pedestrians?

Safety and Mobility are two things that should never be pitted against each other. But that is exactly what is happening: we are trading the safety of pedestrians for the mobility of drivers.

When are we going to get it into the heads of the engineers, the cops, and the driving public that the world isn't going to end if 6 lanes of traffic on Connecticut Avenue have to halt to let grandma cross the road safely?

Robert Thomson: One of the most promising developments in transportation over the past decade has been an increased focus on pedestrian safety. It also has led to a lively debate about rights to use the streets.

On this particular point, I think many traffic engineers would argue that if you force drivers to stop too often, you're creating a safety hazard. Also, pedestrian safety advocates speak about a variety of dangers at crosswalks on multi-lane roads (like East-West Highway in our current example) and they are cautious about changing the configurations.


Springfield, Va.: The split at Eisenhower is a mess. Why does the contractor need to redeck the overpass so quickly? There's plenty of space at that interchange to do a standard 1-year incremental shift technique to redeck the bridge.

The signage in that are is plentiful, but not very useful. If a driver hasn't driven through that area before, it would be very easy to get confused and either miss the exit at Telegraph or get into the wrong lanes at the Wilson Bridge local/thru split.

I was surprised that VDOT did actually repave the ramp lane so it's actually pretty smooth, but I still believe that contractors have slacked off in their planning after getting such great reviews and accolades for the Wilson Bridge construction. The contractors just are not doing the same amount of consideration for the rest of the work in this area.

Robert Thomson: I'm hearing a lot from Beltway drivers about this new lane configuration on the outer loop at the Eisenhower Connector. My plan is to use next Sunday's Commuter page in The Post to explain what's going on and address some of these concerns.

The basic idea is that the Wilson Bridge Project is redecking an overpass there. So the project has created a new lane configuration during this work. Two outer loop lanes to the left go through. The one to the right uses the Eisenhower Connector ramps as a third through lane.

That area, generally around the Telegraph Road interchange, is the lingering nightmare for drivers out of the Wilson Bridge Project. The project was done in stages. This is the last big stage.


Alexandria, Va.: I saw the question from the Franconia Rd. biker, and took a look at the Fairfax City bike map. With the Clermont connector to Eisenhower Ave. closed temporarily, bikers from Franconia and Springfield are really out of luck. The only way that I can see to get to the Mount Vernon trail is going to be a circuitous route through residential streets to get to Beacon Hill road. Or maybe Belle Haven Road would work - I don't know if there is a safe way to cross the GW parkway from there. Anything else leads to busy Rt. 1 or Telegraph Rd. - not safe. Glad I live INSIDE the beltway.

Robert Thomson: I know that the Wilson Bridge Project is suggesting Van Dorn Street as the alternative Beltway crossing now that the Eisenhower Avenue Connector is out of action (for drivers, bikers and walkers). I'm asking cyclists to suggest other alternatives, but think they're going to be limited.

If you've got ideas, drop me a line at drgridlock@washpost.com. I'll make that part of the Commuter page feature I mentioned above.


Arlington, Va.: I was interested in the Wheaton elevator question and this caused me to think of another issue relating to the buttons: in the darkness of the station, the buttons are the same color as the surrounding metal and sometimes people can't push the right button in the darkness. In the streets, you occasionally see a paper sign appended by a station manager pointing exactly to the correct button. It seems easy to correct.

Robert Thomson: Much of interior Metro is too dark.


Olney, Md.: Have they started turning trains back at Silver Spring and Grosvenor again? I'm fortunate to be on the Glenmont side and haven't experienced the sardine-can rides that the Shady Grove folks have had, but we do have to deal with the slow-downs from Takoma to Ft. Totten in the morning. All in all it hasn't been too bad lately. Summer helps. Glenmont parking garage never seems to fill up, even with the continued construction!

Robert Thomson: Yes, I think this situation would be far worse if we were in September, with everyone back at work.

The turnbacks at Glenmont and Silver Spring have been suspended since the crash. The train controllers need more flexibility to make frequent adjustments in the Red Line to compensate -- sort of -- for the slow movement of trains through the crash zone.

The adjustments might include the frequent halts to even out the space between trains. Or -- even less popular -- a sudden announcement by the operator that everyone has to get off so the train can be sent back in the opposite direction to pick up more passengers at crowded stations.


Kevin, Alexandria, Va.: Good day Dr Gridlock!

Was wondering about suggestions for those of us who used to bike through the Eisenhower connector. Will that really be closed until September? Will there be a new path put in place to allow us to get around the beltway without risking our lives on Van Dorn or Telegraph? Thank you in advance for your answer!

Robert Thomson: Through September, I think. No, there's no special bike path to compensate for the loss of access to the Eisenhower Connector.


Re: cyclists: As I was driving in Arlington yesterday, I passed two cyclists (who were staying toward the right side of the road) without any problem. A few blocks later I came to a red light and was thinking how the cyclists would be catching up to me soon so I would have to be careful as we all proceeded forward when the light turned green. It wasn't an issue as the cyclists proceeded to go through the red light where I was stopped and the red light at the next intersection. Please remind cyclists that red lights (and stop signs) apply to them too.

Robert Thomson: Constant problem. I think travelers would show more respect for each other if they saw each other following the rules of the road. If people are going to seek the protection of some rules, they should be following them all.


'If you stop cars too often' BUT if you make pedestrians wait too long: When standing at a 'red hand' pedestrians can now tell how long they have to wait to cross a road - they just look at the countdown from pedestrians crossing the other crosswalk. Often, waiting to walk across a busy intersection, when the metro is facing you and you're in a rush a person will jaywalk dangerously when they have to wait 70 seconds. Obviously someone shouldn't jaywalk - but lets face it such a long wait will make people more likely to jaywalk. Making pedestrians wait a really long time at a light - there are huge numbers of 70 and 90 second lights in DC - will make pedestrians less inclined to wait. 90 seconds is an very long time to make pedestrians wait. Given how many pedestrians are in DC it's shamelessly favoring cars.

Robert Thomson: It comes down to a war over the distribution of seconds. This is one of those balancing acts for safety experts -- and for the rest of us, too. People are going to do what seems most reasonable for them.

I see it on the narrow, lettered streets that intersect with 16th Street NW, a heavily used commuter route. Who's going to wait 60 seconds to walk across a lightly used and narrow, one-way cross street? But the signals are timed for drivers, not pedestrians.


Springfield, Va.: Does Metro take into consideration possible major events when they schedule their repairs on the system? For example, last weekend, the concert at Nationals Stadium had a large crowd, many from out of the area and not familiar with the rail system. Yet the Blue line had to exit the cars at King Street and wait for a Yellow line, confusing and disruptive.

Robert Thomson: Yes, Metro generally does try to balance the maintenance schedule with the events schedule. This weekend, for example, the Green Line, which includes the closest stop to Nationals Park, was the only one without scheduled maintenance. Same thing happens when there are marathons, or big events at Verizon Center. Metro limits work on the lines that have stations closest to the events.


Red light running: A friend's brother, who was 25 and a super cyclist (won all sorts of races) was killed last year because he ran a red light at an intersection and was hit by an SUV crossing on the green. She shot out in front of her, she didn't see him and then couldn't stop. It was awful for everyone. It is just stupid to assume cars see you, bikers (and the same applies to pedestrians. I was hit while running by a car making a right on red without stopping. I now always look to be sure no one is turning before I cross). Is that extra 30 seconds or so worth your life?

Robert Thomson: Intersections are the most dangerous point for all: drivers, walkers and bikers. Don't be lulled because you've got the right of way. Even smart travelers can become victims that way.


Potomac, Md.: I drive home from work through Georgetown outbound on M Street to Canal Road. Almost every day there are cars illegally parked or double parked in the right lane. This causes needless congestion. I think the DC government should do something about this issue.

Robert Thomson: That's only one of many locations where DC should improve its traffic enforcement on illegally parked cars or delivery trucks. I think that out of all of them, I hear the most about 14th Street NW.


Changed commuting: Since you asked about changing commutes, I'm a daily Red Line rider from Van Ness to Judiciary Square. Since the accident, because of the rush hour congestion, I switched my hours at work so now I get on the Metro around 6:50 instead of 7:40 previously. I'm grateful that my workplace allows me to change my schedule in this manner, for it's really made a difference (although it still can be really crowded sometimes, even that early).

Robert Thomson: Thanks. I think the people who are most frustrated by the current situation are the riders on the western side of the Red Line. It's still difficult for them to see how a problem on the other side, between Takoma and Fort Totten, could have such a constant impact on their own trips.


More red light running: I notice a frightening number of bicyclists that run red lights and stop signs without stopping. Isn't that prohibited here? It was where I grew up.

Robert Thomson: Yes. You have not entered a parallel universe. The same traffic rules apply to drivers and to cyclists.


Rockville, Md.: I drove through the Arena Drive/Landover Road interchanges for the first time in a while this weekend, and was wondering if the construction was finished. If the work there is indeed done, I'm very disappointed. The work was supposed to improve flow through the area to allow for the exit at Arena Drive, but all they have done is made it worse! There's not barricade between the "exit lanes" and travel lanes, and the main travel lanes of the beltway are reduced from 4 to 3 (see the term bottleneck). One of the "exit lanes" does continue straight through to remerge with the travel lanes, but only the drivers that have been through there a couple of times would know that, and that lane still gets tied up with merging traffic from the exits.

I'm hoping that they still have some more work to do through there, but from what I can tell, this 2-year construction project has just made things worse!!

Robert Thomson: There's something very odd about that configuration. I need to take another look. Here's what I found on a recent drive along the outer loop: You come to a point where three through lanes go off to the left, then there's a broad white line, and then there's another lane off to the right that looks like it's going to be an exit-only lane. But it isn't exit only. You can stay in that and go through.

Many of the locals would get used to that. But this is the I-95 corridor. Lots of drivers will use it a couple of times a year, and will get confused, hit the brakes and move left quickly.

This reconstruction is part of the plan to make Arena Drive accessible year road, not just for FedEx events. To accomplish that, the Beltway lanes had to be reconfigured. But this issue about the confusing lane divide is coming up a lot.


Arlington, Va.: RE: Fewer 8 car trains

The Orange line has many fewer 8 cars trains running. What is really frustrating is that the "next car" signs will post an 8 car train, then a 6 car will pull in, forcing everyone at the end to rush towards the middle to get on an already extremely crowded train.

There have also been a lot of "corrections" on the next car signs where it shows cars coming quickly every few minutes during rush hour, then revising the information to show longer delays.

Just because the signs say a lot of 8 cars trains are coming regularly, doesn't mean we don't notice they're not, Metro.

Robert Thomson: That was one of several responses to my question about whether riders think they're seeing fewer eight-car trains since the crash.


Eight car trains: There are definitely fewer 8 car trains on the red line during the evening rush. Every other train seems to be a 6-car. This is making it dangerous to change trains at Gallery Place as the crowding on the platform has been terrible -- on Thursday I was almost not able to walk to the end of the platform to get to the yellow line.

Robert Thomson: But this one confuses me a bit. If indeed every other train is an eight-car, that's really good. In fact, I think it might be an improvement in service.

On Gallery Place: Right now, I think there's a problem on the Red Line level because all the trains are pulling to the front of the platform, and people who entered the platform at the rear are rushing forward to catch up with the last cars of the six car trains. Metro needs to engage in more platform management there.


Arlington, Va.: Forgive my upcoming rant, but can I just say how much I hate 95?

Yesterday, on a Sunday, I drove from Pentagon City to Woodbridge, and what should normally be a 25-minute drive door to door took me an hour and 15 minutes! No accidents were visible on 95 southbound, but traffic was at a virtual standstill from the Springfield Interchange all the way down to the Occaquon River Bridge, where traffic inexplicably picked up again, with no backups, accidents, or heavy volume to speak of.

I know that 95 south of D.C. is notorious for this kind of erratic traffic behavior, but I genuinely cannot understand why. Trying to get down 95 yesterday afternoon was about as bad as trying to drive it during evening rush hour! The only thing I can think of that could halt traffic to this extent would be the lane drop at the Fairfax County Parkway exit, but how, I ask you how, could traffic crawl and crawl to an arbitrary point along the highway, then suddenly thin out, with no visible cause for a backup?

Again, please forgive my rant, but this is just one more reason I try to avoid 95 southbound like the plague.

Robert Thomson: I-95 in Northern Virginia doesn't do very well under any circumstances. The current widening project should help somewhat. So should the proposal to convert the HOV lanes into High Occupancy Toll lanes and extend them toward Fredericksburg (eventually).

But it's hard to design the roadway for its many purposes. It's a Washington commuter route and the East Coast Main Street.


Wheaton, Md.: re: Extra elevator buttons.

At least in the case of Forest Glen; there are several "safe havens" between the surface and the platform. These are rooms with separate ventilation, with stairwell & elevator access.

The idea is you could evacuate from a trackside fire, climb part way up; then take refuge.

A further possibility is the elevators stop at intermediate floors with mechanical equipment, such as air condition units, etc.

Robert Thomson: Thanks Wheaton.

Off and on during the chat, we've been exploring the mystery of the Wheaton elevator buttons.


Nat's Game: I went to a Nat's game on Saturday. Drove to Greenbelt so I would not have to switch trains. Getting there was fine. Because my back was hurting left at 8th inning so I would not have to stand. First there was someone telling me where I had to stand to wait for train. (Okay I could live with that even though I might not want to ride in first car). However the train that was marked for Greenbelt made us all get off at Mt Vernon Square and wait for a packed Greenbelt train. (So I ended up standing anyway) The Nats have enough problems getting fans without the Metro discouraging people.

Robert Thomson: At the ends of the games, Metro sends a bunch of eight-car shuttles through Navy Yard to Mount Vernon Square. There, everyone has to get off and wait for a through train to Greenbelt, which is likely to be a six-car train. The eight car train turns around and goes back to Navy Yard for a repeat.

This makes sense to me. It cuts down on the crowding on the Navy Yard platform. Also, it maximizes the number of cars serving the big transfer points at L'Enfant Plaza and Gallery Place. The train displays should say "Mount Vernon," and the train operator should be making frequent announcements.


Red line: It does seem that there are fewer 8 car trains, though that might just be bad luck in my timing in the mornings.

The only time I've seen the "pull up to the front of the station" practice be a problem is at Gallery Place on the westbound Red Line because that pushes the train and people well past the transfer escalators to the green/yellow lines.

Robert Thomson: Yes, that's a better description of the Gallery Place problem than the one I tried higher up in the chat.


Alexandria, Va.: Cyclists are vehicles--so they have the right to be on the roads. Following the rules of course. The trails have a speed limit and most of those riders travel too fast for the trails. Cyclists have the right to travel in the lane. Passing on a twisting road is a bad idea period. If you're in a hurry pick another road.

Robert Thomson: That's fair. Maybe idealistic, but fair.


Centreville, Va.: Is it illegal to use a divided exit/entrance lane as a "piggyback" to get ahead of traffic? On 28N going towards the toll road interchange, traffic often backs up to the exit for the Udvar-Hazy Air & Space museum, waiting for Frying Pan road traffic light. I see a regular stream of cars taking that exit, but they do not go on to Air & Space parkway, but instead head up and merge back into traffic, having leapt past 20-30+ cars.

The completion of the Frying Pan interchange should halt this, but this is not the only place in the area I've seen it happen.

Robert Thomson: I think that is legal. (Others can correct me, but I don't read a traffic violation in that.) It's just more trouble than I'd go to -- the merging back into traffic part -- for a slight gain.

By contrast, this is illegal: Pulling into a left turn lane at an intersection. Then pulling ahead of drivers in the through lane when the light turns green.


Arlington, Va.: I'd like to reintroduce the need for "walk left, stand right" signs on Metro escalators, especially for those stations frequented by tourists and non-locals.

From the tourists I've talked to who have been caught off-guard by this commonly understood yet unadvertised rule, they think it's a logical and rational approach to traveling the escalators, and would be more than willing to abide but it--as long as they're made aware of it in the first place!

Robert Thomson: Metro is circumspect about publicizing our way of doing things, because the transit authority would prefer that you not walk on the escalators, for safety.

But we do have those announcements that say something like: New to Metro? You'll notice that most people stand to the right on escalators.

My real peeve is people who come to a complete stop as they step off the escalator. Now, there's a safety hazard.


parking meters: Dr. Gridlock- I recently had to start driving to work, and am a bit amazed by the city's assumptions of drivers who park on the street. The new fee machines don't appear to be as wide-spread across the city as one would hope, and they raised the parking meters to 8 minutes for a quarter. Who in these days travels with a sack of change? It would take 15 quarters to park for 2 hours at a 2-hour meter. I'm not criticizing the city for making ends meet, but do they really think people have pounds of change in their cars or wallets? J

Robert Thomson: The green fee machines are becoming more common. Odd that they don't take green. It is indeed an inconvenience to haul so many coins. As an infrequent user, I also find the instructions a bit complicated.


Response to the comment on pedestrian waiting times: It's true that pedestrians are more likely to jaywalk at a long light. But it's equally true that if you try to force drivers to stop at every block you increase speeding (as people floor it to try to get through as many lights as possible), you increase red-light running (as people get fed up with being stopped all the time), and you increase pollution (from idling vehicles) and traffic congestion (because the ideal is to synchronize lights in a "green wave" on main thru streets to promote keeping the traffic moving).

I think the problem we have is that so many people adopt an "either/or" mentality instead of trying to look at the whole picture. You can't argue with a straight face that cars should be required to stop immediately whenever a pedestrian presses the button at a traffic-light-controlled intersection--otherwise nobody would ever get anywhere.

Robert Thomson: Ask a traffic engineer about how traffic signal time should be distributed, and he or she is most likely to start the answer with an exasperated version of, "We can't manufacture seconds."

Drivers coming to intersections from different directions and walkers on the corners all want a bigger share of time.


Robert Thomson: Travelers, Thanks for all your questions and comments. I'm going to head off now to check those issues you raised about the Beltway at the Eisenhower Connector in Virginia and around Route 202 in Maryland.

Please come back and join me again next Monday. Meanwhile, I'll look over the many questions and comments that I didn't get a chance to publish today.

During the week, join me on the Get There blog. And stay safe.


The Dr. Gridlock column receives hundreds of letters each month from motorists and transit riders throughout the Washington region. They ask questions and make complaints about getting around a region plagued with some of the worst traffic in the nation. The doctor diagnoses problems and tries to bring relief.

Dr. Gridlock appears in The Post's Metro section on Sunday and in the Extra section on Thursday. His comments also appear on the Web site's Get There blog. You can send e-mails for the newspaper column to drgridlock@washpost.com or write to Dr. Gridlock at 1150 15th St. NW, Washington, D.C. 20071.

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