Post #400: A few corrections regarding traffic and traffic calming.

Posted on September 29, 2019

When the facts change, I change my mind.  What do you do?”  When seemingly knowledgeable readers offer corrections … I make corrections.

1: The Transportation Safety Commission (TSC) has never been asked to act proactively to prevent a problem.  Implied in Post #394 and Post #395.

False:  An informed reader tells me that the TSC proposed pro-active traffic control measures in at least one situation:  Attempting to limit cut-through traffic in the area around John Marshall Dr NE/MacArthur Ave NE/McKinley St NE (and Talisman Rd.) in anticipation of the road closure and construction improvements of Beulah Rd.  Vienna and Fairfax added speed tables to the area prospectively.

It’s worth putting a pin in this one for several reasons.  First, it shows that TSC can act prospectively, and is not strictly bound by the rules of the Vienna Citizen’s Guide.  Second, you can’t find any trace of this, on-line, on the Town’s website or elsewhere.  (Or, at least, I could not, after considerable searching).  On-line minutes for the TSC only go back to 2017.  This came to light purely by chance, as somebody who knew the facts happened to read my post and was motivated enough to set me straight.  Absent an easily-accessed written record, Vienna’s institutional memory is slowly erased as citizens move onto and off of various boards and commissions.  I think that’s inefficient and unfortunate.

2: There’s no plausible explanation for the contradiction between a) the perceived increase in the length of backups at the Maple/Courthouse light and b) VDOT data that show no increase in traffic on that road.  Implied in Post #396.

False:  A reader sent me one possible explanation.  The white lane striping on Kingsley effectively prevents cars from forming two lines at the Nutley/Kingsley intersection, encouraging traffic to filter through the side streets up to Tapawingo or Courthouse.

In the past, two lines would form, for left turns and right turns.  Now, those turning right (north) on Nutley have to wait in line with those making the much-more-difficult left (south) onto Nutley.  And, in general, the length of the queue at that intersection increased for all individuals.

In the case of my correspondent, he no longer takes Kingsley to get to Nutley northbound in the morning.  Instead, he heads up (north) to Tapawingo or Courthouse, and then to Nutley. If enough people did that, it would increase the traffic entering those roads via the neighborhood streets.

Depending on where VDOT habitually sets up its traffic counter(s) on Courthouse, that traffic filtering up the residential streets, from the south, could plausibly slip onto Courthouse without being counted by VDOT.  At any rate, so far, that’s the only explanation I’ve stumbled across that would explain how the apparent backups at the light appear longer, but the objectively counted traffic has not increased.

3. Stop signs are a cheap and effective means for slowing down traffic and improving pedestrian safety.  This was more or less implied in Post #395.

Maybe yes, maybe no.  For the first time, I heard an explicit contrary view that stop signs control speed:  “People notoriously blow through unwarranted stop signs.”

I have always thought of myself as a fairly mainstream kind of guy, but this shows what a sheltered life I have led.  It never even occurred to me that a significant number of people would simply ignore a stop sign.  I mean, what kind of a person drives through a stop sign?  I’m such a nerd, I stop at stop signs even when I’m bicycling.  Which is hardly the norm for adult bicyclists.  (I use a common motorcyclists’ rule:  one foot must be placed flat on the ground.)

The bottom line is that some stop signs may have little effect without active police enforcement.  And that significantly limits their effective use, and makes them a far more costly control measure as well.  As I calculate it, we have about one police officer, per shift, for every 32 acres of Vienna, assuming all they do is traffic enforcement 24/7.  Given our low crime rate, I wouldn’t exactly say they are spread thin, but clearly they can’t provide much enforcement at the typical stop sign.

That said, while some people will blow through stop signs on neighborhood roads (as was reported on Roland Road in my neighborhood), I bet people would think twice before doing so when there routinely are witnesses.  Which means, in practice, on an arterial roadway.  So while stop signs may not be fully effective in the depths of the neighborhood, when traffic is sparse, I would not ignore their potential along a major thoroughfare like Courthouse.  Certainly, I’ve never seen a car blow through the three-way stop at Courthouse and Locust.  Based on that, I’d bet a stop at (e.g.) Courthouse and Ware would be routinely obeyed.

4:  A double-yellow line indicates a major road, or maybe gets painted as a standard safety measure to “narrow the lanes” visually.  That was in Post #395, in the discussion of traffic on Kingsley.

False:  I have now been told that the Town paints a double-yellow line as a matter of course on all the wider roads.  Because Kingsley is 35′ wide, presumably, it got a double-yellow line without regard to any safety consequences.