Like many northern states we are in the midst of road construction season in Minnesota and of course that comes with the local news outlets obligatory story about how people just can’t seem to get on board with the zipper merging. Even after PSAs aired people still were reluctant to follow step and now traffic cams showing road rage incidents of those not letting other “cut” into the line.
I see this as more of a failure of the current signage they use. They seem to either be “left lane ends ahead, merge right” or “right land ends ahead, merge left” which is just a mess waiting to happen IMHO. The righteous rule followers will immediately get over as instructed and then start to get peeved as others speed on by.
Couldn’t this all just be resolved by changing the signage to “lanes merge ahead, use both lanes”?
You wouldn’t have people thinking they were in the “proper” instructed lane and people would be more likely to stay in both down to the zipper point.
Oh, you sweet summer child.
For several years now we’ve had “USE BOTH LANES” signs leading up to zipper merge locations, and still there are lots of people who merge early and then get pissed off at people who don’t and expect to be let in when the other lane actually closes, at the big sign that says “MERGE”. There’ve been PSAs on the subject as well.
I have no idea what the solution is, aside from hammering on the point in driver ed and waiting several decades for driving culture to change.
As the linguist Geoff Pullum once pointed out, “USE BOTH LANES” has its own problems:
Since each reader of the sign is an individual driver (it really isn’t a driver’s business whether other drivers are reading particular signs or not), no driver who sees this sign is capable of obeying it. Setting aside lane straddling, we can assume each driver is in a given lane. What is the sign telling her to do? Switch to the other lane? Merely be aware that she could have chosen the other lane? What purpose does that serve? The authors of the sign have lost sight of the difference between their view of the scene (they would like traffic to be moving smoothly with 50% of the cars in each lane) and the individual driver’s view (I’ve chosen this lane; is that permitted?).
I wonder if there’s a cultural difference between California and Minnesota. In my observation in places where the road narrows from two lanes down to one, people here are totally on board with the zipper merge. Maybe it has something to do with our infamous traffic, which almost necessitates utilizing all the lanes.
Maybe change it to “Don’t merge yet!”
If they want drivers to behave in a symmetric fashion, perhaps they should set up a system that’s actually symmetrical. Or at least a system that looks symmetrical to the people merging. Instead of having one lane that obviously continues and one lane that obviously ends, they might squeeze both lanes into one new temporary lane that straddles the two permanent lanes (repainting the markings as required). Then, a few hundred feet farther down the road, make that temporary lane diverge right or left again as the situation requires (preferably but not necessarily out of sight of the merge spot).
The Tappet Brothers, Click and Clack, of NPR’s Car Talk fame, argued the problem with the zipper procedure is the engineers hold that efficiency–zippering–is the important issue, while many drivers hold that the moral issue–wait your turn–is more important. The brothers sided with morality. My view depends on which lane I’m in.
There’s a zipper merge for a lane closure over a bridge on the highway about 15 or so miles out of town. They close the left lane and merge to the right but then shift the one lane to the middle of the bridge. It would make a lot more sense to merge both lanes to the center from the get-go. (Although that would mean having to change the lane markings further out.)
As far as signage goes, they have “Late Merge Ahead” a mile or so out, then the “Take Turns” signs closer to the merge point.
I see signage like that occasionally.
My solution is that I just use the lane to the end. Somebody will let me in. I’m in Chicago, so you’d think there are some hotheads here, but so far, after so many years, nobody gives a damn. I get irritated when people decide not to wait back with everyone merging onto, say, the Stevenson to the Kennedy (I-55 to I-90/94). There will literally be a line of cars about 50 deep and a few jackasses will scoot along the left and sneak in at the last possible second. And there will always be vehicles happy to let them in. So, yeah, when I merge properly, I don’t give a rat’s ass, and someone will always let me in.
I think something like, “Stay in lane until merge”, followed by “Merge” might do the trick. Signs like, “Left lane closed ahead” just encourage (some) drivers to cut right immediately and then get annoyed when someone uses the left lane to get ahead of everyone and then expects to zipper merge.
I’ve never understood the alleged advantages of the late-merge. Smooth zippering, yes. But not the as-late-as-possible part.
The speed of traffic will be limited by the single lane ahead. And it will have the most throughput when cars are moving at speed and nicely compacted. A late merge seems less likely to accomplish this than if the cars had done their jostling for position ahead of time. Making maximal use of the two lanes doesn’t accomplish anything if they’re going at half the speed.
Which is another disadvantage of a late merge. A single lane at 60 mph is better than two at 30 mph, since individual cars will spend less time on the stretch. But with a late merge, cars could be stuck for many miles at the 2-lane speed before they get to the single lane and speed up again.
I think I have the solution. As soon as the first Merge Ahead sign appears, put rumble strips on the lane that’s ending. As you get closer to the actual merge point, make the rumble strips more frequent and more obnoxious. That encourages the zoomers to merge earlier in the process, thereby satisfying the moral righteousness of the through-laners, who want everyone to merge at the first chance.
The problem is that for a zipper merge to work, both lanes have to be going approximately the same speed, and adjust the speed to make gaps for the people needing to merge. Unfortunately, this is not what happens. Instead, the ass-clowns in the “open” lane use it as an opportunity to shorten their journey by rapidly passing all the cars in the “waiting their turn” lane. If the ass-clowns would just get on board with actually using the disappearing lane with courtesy, zipper merge would work. Alas, that is not human nature. Human nature is to be an ass-clown.
This is the answer. Different signage won’t do anything for drivers who think the ones who zip to the end of an empty lane are cheating.
I don’t understand what zipper merge is supposed to accomplish. How does it increase the throughput of the single lane? That’s the limiting factor when there’s a contentious merge point. I don’t see how people lining up in both lanes to take turns is faster than people trying to merge as soon as they’re aware of the lane ending. The only thing that I see zipper merge doing is moving some of the backed up traffic from one lane to the other. If you say “well at least there’s less wasted roadway” - so what? What purpose is there in having 10 cars in each lane waiting to merge? If people merge early there’s at least a chance that traffic flows at the best rate possible. If people wait to merge until the end, whether because there’s a line of cars doing a zipper merge or not, then doesn’t traffic necessarily have to slow when they’re changing lanes from a stop? If traffic can flow naturally such that no traffic is stopped in the merge, I don’t see why it would matter.
That’s how I view the situation, and yet we’re constantly pelted with PSAs to tell us to zipper merge, as if it’s been proven that it’s better and there’s no real debate over that. Please, let me know in what way it’s better and why my reasoning is wrong.
Those are not mutually exclusive.
But this is exactly why using both lanes until the merge point solves the problem, or would, if people would actually do it. Because then no one is zipping to the end in an empty lane. There is no empty lane.
An illustration:
When this discussion on zipper merging arises in my local subreddit, r/Saskatoon, people will frequently comment, “I don’t know why people don’t understand how to zipper merge, because they do it all the time at Spadina and 25th.” If you click on my google maps link, you’ll see that Spadina northbound must turn onto 25th eastbound and cross the bridge. (If you didn’t want to cross the bridge, you turned a block earlier and took the bypass under the bridge to proceed north.) Those making this right turn have a yield sign, and must give way to through-traffic on 25th. However, at busy times there is unbroken traffic on 25th, and by convention in that circumstance traffic in the right lane of 25th will alternate with traffic entering from Spadina. There’s no signage to that effect, nothing to enforce this convention, and yet it happens without fail. Of course, because of the structure of the road, no one here is seen as “cheating”, and so people are perfectly happy to zipper flawlessly.
I submit that if you placed barriers to prevent lane changes for the last km or so prior to a freeway zipper merge and before the ‘lane closed ahead’ signs, and only allowed merging at the point where the lane actually closed, then traffic would zipper perfectly with no fuss.
If traffic is light enough that it can all merge into the remaining lane/lanes without backing up, then merging early is fine and even preferable. But if it cannot, and traffic is going to back up, then merging early creates the situation where early merging causes the continuing lane to be more backed up than the ending lane, resulting in “cheaters” who drive to the end of the empty but ending lane, and then conflict when people who merged early try not to let the “cheaters” in. This doesn’t change the total traffic throughput of the remaining lane/lanes, but can result in road rage and actual accidents if people force the issue. It can also cause upstream traffic issues, such as if the continuing lane backs up much further than it would if both lanes continued to be used to the point that upstream exits/turns are blocked.
I don’t have anything to add, I just always feel compelled to post in threads about zippers.
You’d have to close the lane to create the rumble strips and then again to smooth them out. The closure would keep “backing up” until you fell off the edge of the earth!
hmmm, this is all very enlightening. I for one thought that we were supposed to merge early and I definitely get pissed at the cheaters. So I guess I am part of the problem.
But the psychology goes even further for me. Even with this new enlightenment, I will still be reluctant to merge late for fear of being seen as a cheater and for others refusing to let me in. And god forbid I actually have to come to a full stop at the end of the open lane while the traffic in the other lane is still advancing. It would be really difficult to get in then.
Kind of a game of chicken.