My point of zippering is not only to increase throughput (although it seems it does increase throughput–see studies above). But also to increase fairness and decrease anger on the roadway. Fact is, with a congested area with no clear singular merge point, people are going to merge all over the place and there will always be drivers who take advantage of the open lane. Some will merge at the merest hint of a lane closure, some will ride the lane closure a mile or so, others will zip past everyone and merge at the very end. The net result is everyone is jumbled out of order, perceived slights cause stress and irritation on the roadway, and the earliest mergers end up being the ones screwed the most for what I would perceive as their lack of common sense, while others would perceive as common courtesy. If everyone agrees to merge at one point (and the variable merge proposal that covers both congested and non-congested traffic flow seems the most comprehensive option), we don’t have these problems.
can’t believe this is even a question.
Zipper merge. I drive in Europe a lot and it is common and works well.
One of the added benefits is that if you try to keep a single long line of early mergers it ends up blocking other intersection and exits. Using both lanes fully makes this less likely.
The rule that we all learned in childhood, which applies here, is “take turns.” Left lane, right lane.
The fact that one driver contributed to slowing the right lane down by merging earlier does not give that driver a privileged claim on that lane.
Depends. I know quite a few roads (State Highways) that go from 2 lanes to one lane (in each direction of course). For the most part, it is no problem to merge early and continue going the speed limit. Some folks see this as an invitation to pass people until they get to the merge point. Where they slow down or practically stop. At that point, the THROUGH traffic that performed a merge in time has to slow down for the idiot to get in, or he barges in from a slow speed and causes everyone else to hit the brakes.
Those are the idiots that I deal with more than the city, construction problems.
Agreed. This whole mess and who’s right/wrong would be completely solved with better signage.
“Left lane ends- Merge right” is just too vague. Merge now? Merge when I can? Merge at my convenience? Get in line behind everyone else?
Maybe something like “Left lane ending- merge immediately to form line” would direct people better if that’s what they want them to do.
Or if they prefer people to use the zipper system don’t even tell the drivers which lane is ending. “Caution- Lanes merging ahead- use both lanes until merge point”.
Leaving it vague like it is just asking for trouble.
And where did you wait for your turn?
Whats that you say? In the queue? Correct. Have a dead kitty.
Er, I also learned how to take turns by sharing. You can also share the road by taking turns to merge.
Everyone seems to select between the options of get in line asap or wait to the merge and use a zipper but I’m wondering why there has to be a line at all. Certainly for not all cases (very high traffic density), but for many it seems to me that the line is being caused precisely because people slow down to let the people who drove to the merge point in. I mean, if there is just a single lane of cars with no physical obstructions, why would it creep along at stop and go rates?
Basically, I’m reiterating pyromyte’s view that the important thing is to keep the traffic flow steady. The best method I can see of doing this is what I would call a “rolling zipper” where each cars slows down just enough to open up extra space ahead of him for another car. Then the merging can happen with barely any slow down.
Thought experiment: what would happen if I got into the non-line lane, but matched the speed of the traffic in the queue and zippered at the merge point? Would the lane next to me start to speed up?
But that’s exactly the case discussed in the OP. Note:
I would suggest that a line is not an indicator of a true traffic bottleneck as it’s possible the (optimal) outbound traffic flux is still greater than the inbound. It’s just that someone slowed down at some point, which sent the whole thing to hell. But yeah, I was just talking generally (and specifically about a situation I was in about a week ago).
I think there are too many variables to declare simple strategies like wait to the merge point, or get in line as soon as you see signs to be the most effective. I should probably spend time reading the cites people have given.
Where’s the “raising my hand” emoticon when you need it!
I don’t mind if the person is obviously stuck in that lane and you can tell they are honestly trying to get over whenever they can, but there are the ones racing down the lane with no intention of doing anything but cutting to the front of the line. Fuck 'em!
Both sets of dumbasses should be beaten severely about the kidneys with rubber truncheons.
Yep. Exactly the sort of attitude that could be avoided with a single merge point solution. I can see you getting upset if somebody is using the shoulder to jump the queue–that annoys me, too (although I would never block them because, for all I know, they have a serious emergency.) But in a perfectly legal situation (and one where our instructor in drivers ed specifically told us to use the merge lane until the merge point)? Nah.
Generally speaking, this is always what is best, at least when traffic is heavy, regardless of what nay-sayers in this thread who think that merging is like queuing in any way at all. However, some states ARE starting to use language like what you have suggested for clarity. See this report, this one, and this one. And There are numerous others.
Multiple studies agree that in heavy traffic you should use both lanes to the merge point and then zipper. Late merging works, and it is better at overall reducing slowdowns and decreasing collisions.
Blocking people from doing that is most assholish behavior and is very dangerous.
This is what Oklahoma requires as far as signage, and there are multiple signs and warnings-to-merge placed over a couple miles prior to the linked sign (usually). There is zero doubt as to the point when one line should be formed. I laugh my ass of when there’s a cop sitting there waiting for those who blaze on by a formed line - cop just steps out of car and waves 'em over to have a little get-together. It is not infrequent to have a cop car w/ off-duty officer present at area of merge point with lights flashing to help prevent accidents (paid for by construction company, iirc).
From the website of that image (mid-page, fwiw): * However, a research paper from the University of Kansas found that the “merge now state law” signs do not result in earlier merges, but do reduce conflicts at the merge point and that improves the flow of traffic. The new signs carry the weight of law, that’s why they are partially in black and white. *
Ignore those merge signs at your own risk here in Oklahoma. Towns want their income, trust me…
If anyone’s interested, there’s a urban planning/social psychology book called Traffic that claims the zipper method is hands down the most efficient way of dealing with merges. It blames people who refuse to let people ‘‘cut in’’ as the most significant source of traffic congestion.
I agree! 
Though I almost got rammed by someone trying to butt in front of me the other day.
Yep, I have seen folks get out of the line of steadily flowing traffic and try to move up 10 or 20 cars and try to merge back in. That slows everyone down.
It causes terrible surge in the traffic flow and in general screws everything up.
Those idiots should not be let back in. Let them learn their lesson.
I too have driven in Europe and can agree. However, one of the significant differences between drivers in Europe and America is education and experience. In Europe, getting a driver’s license is expensive and difficult. In America, it is nearly a birthright.
Like all of you, I have seen quite a bit of stupidity and careless driving in situations like this. Light traffic and an obvious lane closure a quarter of a mile ahead and yet people will drive right up to the huge flashing arrow and seemingly suddenly realize that they have to change lanes.
Here’s another idiotic thing I can’t fathom: people who drive behind a city bus who are apparently shocked when it stops in the middle of traffic at a bus stop. They frantically attempt to pass the bus at the last second or sit behind it with their turn signal on pathetically waiting for someone to rescue them from their stupidity.
I feel no sympathy for them. They do, however, make me nervous because I feel that if they’re stupid enough to get into such a fix, they might be equally stupid trying to get out of it.
Okay, getting out of line to try to jump the queue a bit is totally over-the-top asshattery, far and above and beyond the people who drive up an open lane as in the OP. At that point, the rubber and the beating and the kidneys mentioned upthread can be involved.