Striping at beginning of turn lanes

[1995hoo]

I found myself thinking of this issue yesterday after discovering that a repaving project had resulted in a change in turn lane striping. What I'm wondering is whether there is a standard or guideline for when the beginning of a turn lane is striped off in a way intended to discourage people from driving there. I can think of some situations where this sort of thing is logical, and in one of those cases the striped area is emphasized with plastic bollards. That particular turn lane (on westbound VA-236 between Woodburn Road and Prosperity Avenue in Fairfax County, Virginia) is one where there are two right turns in rapid succession onto two different streets and VDOT wanted to discourage people from using the first turn lane to turn at the second road, essentially as a lane to bypass traffic. If you're in a right-turn-only lane, you're supposed to turn at the first street you reach, but since Prosperity is the more important thru route there, more people turn onto that road. (Street View of Woodburn/Prosperity here. Note beat-up plastic bollards on far side of first intersection.)

The turn lane that prompted me to think of this is on Manchester Boulevard in Fairfax County. First, a satellite view of how it looked prior to the repaving. The turn lane in question is on the road running across the photo (Manchester Boulevard) and it's the right-turn lane on the westbound lanes to the left of the intersection at the center of the image. Notice how there was nothing legally preventing you from making a right turn out of the shopping center and going directly into the turn lane.



Within the past week or two, the road was restriped following a paving project and the turn lane has now been truncated. See image below.




Similarly, on the far side of the next intersection to the west on the south side of the road, there are two turn lanes and their start is striped off in yellow:



This yellow-striped area is routinely ignored by almost everyone, such as the guy to my left this morning:




What I'm wondering is, what prompts this sort of design? I can understand how in the first example above there might be a desire to emphasize to people that it's illegal to get into the right-turn lane prior to the shopping center entrance and then to go straight in order to turn right at the next light (similar to the example I noted earlier in this post), although that sort of thing isn't really a big problem at that location. Let's be realistic, too—anyone who makes a right out of that shopping center and wants to go into the right-turn lane is going to ignore that striping and will just drive through there. It's really the second example that has made me scratch my head ever since it was paved and striped that way because there doesn't seem to be much need for, nor benefit from, that yellow-striped area, and indeed when the left-turning traffic backs up far enough to fill the turn lanes, I think people who pull onto the striped area to queue up are doing the courteous thing because it gets them out of the way of drivers who want to go straight.

[briantroutman]

I can't comment on whether there is a standard or guideline, but in general, I imagine the reason for restricting a turn lane through striping would be to consolidate lane entry movements to a single point (where the lane is at its full width) rather than allowing motorists to try to squeeze through a too narrow space as the lane slowly transitions to its full width.

While I don't like lanes being restricted needlessly, I do appreciate when markings are decisive.

My read of the particular situation pictured above is that the striping is precisely to discourage motorists in the rightmost lane from continuing straight through to the right turn lane on the other side.

That does beg the question, though, if the entrance to the shopping center is essentially a driveway and if the lane is not restricted through striping, how else do you know that a turn lane is for this intersection? I've sometimes been in situation where a minor intersection preceded a much larger signalized intersection, but it seemed pretty obvious that the turn lane was for the larger intersection.

[1995hoo]

I can't comment on whether there is a standard or guideline, but in general, I imagine the reason for restricting a turn lane through striping would be to consolidate lane entry movements to a single point (where the lane is at its full width) rather than allowing motorists to try to squeeze through a too narrow space as the lane slowly transitions to its full width.

....

Ah, yes, that is very sensible, though of course we all try to squeeze through anyway because of people who leave way too much space between cars when they stop for a red light such that it's hard to get into the turn lane! Striping the area clearly establishes that if you drive there and cause an accident, you're in the wrong for driving where you weren't supposed to. Good point.

That does beg the question, though, if the entrance to the shopping center is essentially a driveway and if the lane is not restricted through striping, how else do you know that a turn lane is for this intersection? I've sometimes been in situation where a minor intersection preceded a much larger signalized intersection, but it seemed pretty obvious that the turn lane was for the larger intersection.

In that particular case, where there is a traffic light at the shopping center intersection (you can see the mast arms' shadow in the first image above), presumably the idea is that you know you're supposed to turn because you have to turn at that light. The average driver doesn't see it that way, of course! "It's a right-turn-only lane and I'm turning right up ahead."

[Big John]

For the right side.  It helps channelize traffic so only turning traffic is in that lane with less confusion.  And better for maintenance for having full-out pavement with a short hatched-out area.

The left side makes no sense to me as it is a widening anyway for left-turning traffic.