It’s weird when people think getting places fast or first is the point of driving.
“Safe” is the word you’re looking for. Then, as fast as safe will calmly allow.
Merging at the last minute is the correct way to do it.
Zipper merge, you fucks!
Nothing about the zipper merge says, “last minute”. It is wholly and entirely about matching speeds and making room.
Guess what dictates the speed of the lane that gets to travel forward? The amount of traffic that gets to travel… in that reduced number of lanes.
The people racing to the end of the closing lane are doing nothing but increasing traffic density, which directly hurts the effort of zipper merging. If it’s going from two lanes to one, the density MUST halve somewhere if traffic is full. That’s never going to happen at full speed if there are assholes wedging in at the last second and pushing traffic density past what people comfortably go full speed at.
Hint: it is not bumper to bumper on the highway.
Again: Merging at the last second does nothing but push traffic density up. Often past comfortable densities, which will slow traffic. It’s the exact same reason rolling stops happen even without traffic accidents or lane closures in dense traffic.
Last minute is absolutely part of it. Use the available queueing space to keep congestion from spreading. I don’t know where you drive where bumper to bumper didn’t happen, though.
No it is not. Ever. You cannot magically add throughput by cramming in ahead of the bottleneck. That ONLY increases density, which DEMONSTRABLY reduces speeds.
Guess what happens when speed goes down? Throughput also goes down! You cannot magically add throughput by filling space beyond what is reasonable for the speeds you want to go. That’s not how humans work.
It’s not about throughout. You want previous intersections and ramps to be free. The extra lane is car storage space. If one lane is stopped and the other is free you absolutely move up to the merge point. Safely, mind you. The speed limit is way too fast, 30-40 kph is enough. Merging early causes shockwaves that turn into full blown stops upstream. Plus you block the whole lane until you’ve merged.
I’ve done traffic control systems for almost a decade so I actually know a little about the subject.In some situations, it’s not all about throughput.
Though traffic congestion is ALWAYS about throughput. You want less congestion? Then don’t rush to the end of a closed lane and cram in. That ALWAYS hurts throughput, which ALWAYS increases congestion. Period.
Sure, if traffic IS backed up to other roads, then absolutely, fill up the closing lane and get off those other roads, though understand that filling up that lane will, always, always hurt congestion if throughput is already struggling.
Zooming to the front to try to merge at the last minute and creating a choke point that stops traffic for half a mile is NOT the correct way to do a zipper merge…
You shouldn’t be able to, because both lanes are full and moving at half speed.
Except people do it anyway, I’m surprised so many people are trying to pretend they’ve never seen this.
Traffic isn’t some collective consciousness thing that moves like a well-oiled machine. People are selfish and do what they think is to their best advantage, even if it causes the overall traffic conditions to be worse.
But they’re not. Zipper merges might be the efficient thing to do, but here everyone is taught to merge early so the guy doing 70 km/h in the empty lane when the speed limit is 50 and then demanding to merge is generally seen as an asshole by everyone else, especially because those people usually don’t wait for you to make room either, they often just start merging into other cars knowing someone will hit the brakes.
I would agree with this if literally anyone else knew how to zipper merge
The solution is educating people about zipper merging, not getting angry at those who actually do it.
Here in Poland it works quite well, at least when the merge is expected.
But we have signs reminding people of that and they also display this kind of driving tips on info boards on motorways when there is nothing more important.
We only started seeing signs in my city telling people to zipper merge, but I was never taught it in driver’s ed, and we really should be.
I wish we had better signage here like you have in Poland.
Depends. If there’s lots of traffic, yes. If it’s sparse enough that you can merge without slowing people down too much, just do it early.
If it’s that sparse then the situation in the meme is a non-issue
…until people make it an issue by speeding up and cutting people off, causing it to bottleneck
Yeah, that’s the big asterisk on the “zipper merging is more efficient” premise. It assumes that things are already bottlenecked. If you have the space to merge early without slowing down, you do that. People trying to force their way in at the last minute (when they didn’t have to) is one of the things that triggers the bottleneck in the first place.
I’ll merge early but also try to go a bit slower than the person in front of me to open a gap which allows me to absorb some of the traffic wave (where flow alternatively speeds up and slows down from people trying to get up to speed only to have to slam on the brakes because some car ahead wasn’t going fast enough to maintain that), as well as leave space for others to merge at speed.
Though I sometimes close the gap if I notice people pulling into the right lane to try to skip the line.
K but people don’t tend to complain about those driving down the empty lane if there is no bottle neck.
Obviously if you’re racing down to cut someone off, that’s just as rude as any unsafe merge, but thats not unique to zipper merging, so is it relevant?
Zipper merge is always the most efficient if people dont prevent merges, regardless of road conditions. It means both open lanes are used to move cars forward until the last moment when they cannot. “Move over early” means less throughput in the system, no matter “how open” one lane is at some point.
By blocking merges, you causes braking, which is what causes traffic. You framing people driving efficiently to prevent traffic as “people trying to force their way in last minute” means its you creating traffic, not them.
You’re arguing from a sense of moral suppority, I.e “I got in line early, you should have to,” not from a sense of efficently moving cars down a road.
Agreed on never being the one blocking merges, but for the merging party, “if people don’t prevent merges” is such a huge caveat that I think attempting a zipper merge at a lane ending at any appreciable speed is impractical at best and downright dangerous at worst.
If everyone is traveling slow already, failing to merge quickly at the lane ending isn’t a huge threat to safety and just a slight hit to efficiency. Most merges I’ve experienced are probably in the 40 to 80 mph range though. In that case, you absolutely do want to take the first decent merging opportunity you can, because waiting to do it until the lane ending can have huge safety and/or efficiency consequences if another good merging opportunity doesn’t open up at speed.
Also, I’m pretty sure zipper merging was mentioned zero times in driving lessons and tests where I’m from, so you should basically just assume other drivers don’t even have it as a concept. If you’re from somewhere where more people practice it regularly, then I can see why you are more encouraged to enforce it as a baseline.
This will only be done right by AI.
It’s rare, but I think they’re referring to when it’s open enough and running at optimal speeds. It happened the other day on a side street during an off hour, the free lane couldn’t cut to the front without going like 70mph in a 40mph zone.
Of course a muscle car did just that, but still.
No.
Throughput is determined by number of through-lanes and the speed at which traffic is moving. Period. Completely.
Filling the merge lane when traffic is already slow does nothing but drive density up, which slows traffic further.
Sure, YOU might save some time by passing a bunch of cars, but it DOES NOT IMPROVE THROUGHPUT.
Zipper merging is about NOT having an area of abrupt speed change. It is not about using up a lane that is going away. Period. Ever.
It’s the same as an on-ramp: If you’re speeding up just to slam on your brakes to merge, that’s not zipper merging!
Someone made a simulator for these scenarios where you can adjust on driver behaviour and see metrics in what is most efficient.
And it shows exactly what I’m talking about. When people are more interested in filling lanes than merging efficiently when one is disappearing, they reduce the throughput of traffic over all.
Yes before the lane is closed. They are not doing that.
No. You are explicitly supposed to go to the very end of the closing lane, and then merge, not before it closes.
Well a closing lane would be marked with an arrow pointing to the lane next to it, and if it’s closed it’s a red X. You merge before the red X. I don’t see a closing lane the same as a closed lane. Maybe it’s a translation thing. And every country is different.
Gave a ride to someone who for one hour kept bitching about drivers who use zipper merge properly. didn’t want to tell him he was wrong.
he was so convinced and fuel by hatred of better drivers.
thank you. the math agrees, too. zipper merges are the way to go!
At a respectable speed though, merge lane is not a passing lane. My rule is whatever speed can be maintained stay with the car speed in the lane to be merged into, jamming the front punishes everyone cueing properly.
The the merging lane is empty for a half km, then it’s proper to drive to the front and merge. If you just drive slow, then you’re a problem for the sake of being a problem.
Drive to the front, match speed, zipper merge. It isn’t hard.
Depends on what you mean by “the front”. Too many people do not know how to look thousands of feet down the road. Probably why so many merge too early.
The assholes that also do not know how to look thousands of feet down the road fly to the end and cram in, which does nothing but further reduce throughput because it slows the lane people need to merge into.
That is literally what a zipper merge is, and what you are supposed to do. Go to the end and merge. If they are “cramming” in, then the people in the lane are not doing their part either, because you are supposed to let people merge.
When people properly zipper merge, traffic will keep flowing. Your complaint about reducing throughput is a “well of fucking course it will” because you’re putting more cars through the same space regardless of where they merge. People who slow down with hundreds of meters of space, then stop and wait for someone to let them in makes the problem worse, not better.
Literally, no it is not. Nowhere does it say you have to get to the end before merging. THE WHOLE FUCKING POINT is to MATCH TRAFFIC SPEEDS AND MAKE ROOM to reduce interruptions. NOT to fill up all available space where ever you find it.
If you fly to the front past a bunch of stopped cars, you ARE NOT MATCHING SPEEDS. Those assholes are not zipper merging. Period.
The people who merge early are not utilizing all space, but THROUGHPUT IS ABOUT LANES AND SPEED. When one lane is disappearing, you CANNOT MAGICALLY ADD THROUGHPUT by cramming in before the bottleneck. Period. Ever.
Pretty confidently incorrect there with your capitals and italics.
If you fly to the front past a bunch of stopped cars, you ARE NOT MATCHING SPEEDS. Those assholes are not zipper merging. Period.
You realize if they were to match speed that would mean they must stop in an open lane, and that would just make everything much much worse, yeah? Thats also pretty much illegal everywhere lol.
That was the respectable speed part. I agree too slow is also an issue.
I’ve been reading this for years, and the hypothesis always seems to be that zipper merging is good because it maximizes road usage. You know what else maximizes road usage? Bumper to bumper gridlock.
Zipper merging, when done properly by enough people, prevents (selfish) others from racing past
People cramming in at he last moment on a jammed highway exit is a different story
Gridlock doesn’t maximize it. Bumper-to-bumper at 80mph does, though
Good luck getting humans to do that, though. Bumper to bumper only makes people slow down due to discomfort, so cramming to the front and increasing density to bumper to bumper will only slow traffic further.
It’s the same reason rolling stops happen on highways even without traffic accidents or lane closures. When density gets too high, people will slow down, and the assholes thinking bumper to bumper at the last second is zipper merging are indeed assholes slowing traffic down.
This article falsely assumes the only options are halting traffic to wait for an opening or dash faster than speed of traffic until the end of the lane closure then just expect someone to allow room so kinda a bad explanation of zipper merge and proper driving etiquette
Not sure if you took drivers ed but zipper merging is not zooming past stopped cars to last second dart over in the shoulder, it’s speed matching the lane you are merging into to weave in like a zipper. Crazy how even the name isn’t informative enough for people to understand the concept
Why have two 1 mile long backups when you could have one 2 mile long backup.
*Taps head
Because the consequences is a low trust society where people hate each other
So if the traffic is slowed down you want everyone to just move over early making it even worse…?
No, you populate both lanes than alternate right of way.
If both lanes are stopped, sure.
If you’re zipping past stopped cars in a lane about to close, you’re the asshole, period.
No, those cars merged incorrectly too early, they’re the assholes since they created the traffic first and are now mad other drivers are doing it correctly.
The amount of traffic makes no difference, if the lane is open, fill it up, that’s the most efficient for everyone.
Just because you made a poor choice doesn’t mean everyone else who didn’t is an asshole lmfao.
I remember an article from a certain parody magazine about “the state is introducing the Velcro merge, because majority is to stupid for the zipper merge” and they photoshopped a street sign with cars in random angles honking at each other xD
I let drivers like this in every time.
It doesn’t cost me anything, and avoids a dangerous situation for myself and everyone around when they inevitably push in regardless.My ego isn’t so fragile I have to flex my power, it’s not my job to teach them, and they wouldn’t learn anyway.
My favorite are the people in large vehicles who decide to be the police of this bullshit methodology and straddle the lanes.
Zipper merge mther fcker!
ITT: people too hyped on zipper-merging to read and comprehend the actual issue being discussed.
In addition to the zipper merge arguments, also note that MOT (management of traffic) guys tend to not be the sharpest crayons in the box, nor the most diligent and responsible. I’ve seen enough “lane closed ahead” signs left up in situations where the lane was absolutely not closed, that I don’t even bother reacting until I see some cones or other indication that it actually is closed.
They read them just fine, but they are special
Why is it always boomers that fail to comprehend the zipper merge?
… Is it the lead poisoning??
Who
Boomer humor. Your post. It’s humor for dimwitted old “baby boomers” who don’t understand that it’s better to use both lanes for as long as possible and then zipper merge.
I call it prep and merge…prepare to merge at speed, then merge when it’s needed
What do you mean
Because it’s counterintuitive. You would think that getting people over early means traffic can just flow easier.
Yeah, but into a road that is more narrow. You can’t fit twice the volume into a pipe half the size and expect the same throughput.
You could reduce the gap between the cars by ~half.
Are you referring to stopping distances?
You said it couldn’t be done, you didn’t specify a need for it being safely done.
Ah, this is where mechanical engineering and civil engineering butt heads.
It was in fact, lead poisoning. That’s where all the angry husband stuff comes from too. That whole generation was literally metally challenge due to the poisoning.
That whole generation was literally metally challenge
Ozzy would like a word.
Oh no, they definitely read it. They just don’t care and expect you to let them merge.
Bonus point for the fuckers that speed up in order to pass as many people as possible before forcing their way into the exit
Few things bring me joy like showing just a wee bit of room to bait those fools to try to cut a dozen people off just to slowly close the gap as they approach my blind spot and force them behind me
I watch people get out of line then dash down the single file all to get 4 cars ahead so they get to work 4sec faster. No sympathy for antisocial scum
Which they can’t do if everybody stays in lane and waits till the last moment.
Because that’s the correct procedure
No its not. If all the cars are in one lane and you drive past all of those cars in the empty lane and then expect all those cars you passed to let you merge, you’re a piece of shit.
Yeah you dumbass. So use both lanes and then zipper merge where they merge
In sorry, but if all the cars are in the open lane and you zoom passed in the closing lane, I’m not going to let you merge. Deal with it.
Lane shouldn’t be clear. That’s the issue, here.
OK, that’s not my fault. I just obey traffic. Again, if everyone is in the open lane and you cruise by in the closing lane by yourself, I’m not letting you merge. Obey traffic.
Why is the other lane open, that’s the problem.
Why would all of the cars be in one lane before the other lane closes? That’s silly
I hate to break it to you, but you have to merge before the lane closes. If it’s 20 feet or 200 feet, you’re still merging before the lane is closed.
Guess how fast you eat up hundreds of feet at highway speeds? In seconds.
If you want traffic to stay at highway speeds, you ALWAYS merge before you HAVE to leave your lane.
It’s the same principle with on ramps. The people racing up an on-ramp just to wedge into slower trafdic are helping no one.
Hate to break it to you but literally every other country on earth zipper merges and it’s far more efficient
Yes, they’re more efficient. They’re also more efficient than rushing up to the end of a closing lane and merging into an ALREADY FULL through-lane. That is NOT zipper merging. It is cutting in line. That will always, ALWAYS, reduce throughput. Period.
You cannot cheat physics and human predictability. Rushing to the end of a closed lane WILL NEVER INCREASE THROUGHPUT. Period,
THATS WHAT ZIPPER MERGING IS YOU DUNCE
If you’re talking about doing it at 60 you can still use both lanes as long as you aren’t following the car in front of you dangerously close or jerks who don’t let merges in there’ll already be enough room to merge. Cutting to one lane early is like people who don’t use the on ramp to accelerate and slow everyone down when they merge then accelerate
The vast majority of situations where people are making faces at the assholes sitting at the end of the closed lane is when traffic is already over-dense and going slow.
In those situations, which are often, racing to the end of the closing lane is just being a line-cutting shithead, and has nothing to do with zipper merging. At that point, they’re literally only butting in on through-traffic.
Because the sign clearly says “lane closure ahead merge now.”
No, it doesn’t. It never would, because NHTSA knows that utilizing all lanes during a lane closure reduces backups. Show me a sign where it tells drivers to merge now that isn’t at the actual merge and I will eat a hat
It does NOT reduce backups. You cannot magically increase throughput by cramming in before the bottleneck. It can reduce how physically long a backup gets, which can keep backups from growing off of the highway. Though you still cannot magically add throughput by cramming in ahead of a bottleneck. Ever. Period.
You can add throughput by zipper merging predictably all day long instead of every car jockeying for position and feeling entitled to block other road users from legally merging and causing all kinds of road rage based holdups though
Zipper merge is best merge you dingus.
The issue is this:
A) Your lane is ending. Drive to the end of the lane and then merge. Simplest reason: why the fuck would they build that much lane if you’re not supposed to drive on it? Alternate reason: you’re just stretching the traffic jam farther back where it could be blocking people from exiting or getting on.
B) Your lane is exit only. Get the fuck out of that lane, you’re blocking people legitimately trying to exit. You’re a cheating cheater and you’re clogging the exit lane.
C) Your lane is not an exit and you want to get into an exit lane. Get into the exit lane as soon as possible. Late merge is just going to clog up a lane and you’re a cheating cheater.
These situations are not the same but people think they are.
But this post’s context is only A, right?
yes.
In Australia if your front two wheels are ahead of the other person’s front two wheels, and you’re indicating to move into their lane - you have to let them in. It’s the law.
Takes a lot of the rage out.
Do you mean “they have to let you in”?
Yes. Thanks.
Oh yes, but there is also the rule that if they are driving a ford ranger sized ute or larger they have right of way to floor it and get infront of you so you have to merge behind.
In a civilized country, that might work (Australia though, really?). It would just promote idiots to race ahead of people here in the States. Im kidding btw. Love you Aussies.
many states have laws that require you to let people merge. they don’t.
Like most things, a zipper merge works only if EVERYONE is abiding by it. Much like they tested and found out that a plane can have all passengers boarded and seated with luggage in about 15 minutes…if everyone followed the rules. But know, every damn over-entitled Karen, Jaxson, MacKhenzie and the rest of their ilk feel the rules don’t apply to them.
Yeah…no, I’ve been waiting in line for 15 min and the guy that went on the other lane to skip the line can suck on my zipper merge
You could have waited less time if you also zipper merged ❤️
And saying fuck you to all the people who are lining up because I’m somehow superior to them? Try to do zipper merge in front of people in any other context and see how quickly you get a nice shove and some colorful words.
Yep. Science says OP is wrong: https://www.acg.aaa.com/connect/blogs/4c/auto/zipper-merge-keeps-traffic-moving
ISTR there being some indication that as speeds increase, merging further away from the “final merge point” can help, but that’s for designing roads with permanent lane reductions, not for temporary lane closures due to construction, accident, etc. But, I also couldn’t find that science when I looked for it.
Who?
Sorry, wrong thread mate. The owl mating convention is over yonder. Two flaps, hang a left and Bob’s your uncle.
Zipper merge works best as long as the people involved understand it and actually want to do it.
another failure of human nature. the tragedy of the commons fails us yet again!
The problem is these people won’t zipper merge most of the time. I always leave 2 car spaces, and the asshats want me to come to a complete stop before they do.
Boomers, they’re called boomers
I’m a tax payer and I’m going to drive in all the lanes I paid for then zipper merge when needed. If we all pile up in one lane because we are too collectively stupid to use all our lanes and zipper merge then we are the traffic we deserve.
Spoilers: You are the traffic you deserve.
The ONLY thing occupying both lanes to capacity does is kinda sorta sometimes reduce how physically long the backup is. Though if there is more traffic than the reduced lanes can handle, it WILL back up, and flying to the end of a lane that’s disappearing and merging into already full traffic only makes you a line-cutting asshole slowing more people down.
Upvoting all of OPs posts because you gotta respect the commitment
I don’t know about you guys, but the teeth an my zipper are lined up ahaid of time and “traveling” the same speed. I would be fine with zipper merge if that where the case, but every time i am in the open lane and the other one closes there are 10 jerks who sped to the end and now feel i should have to come to a full stop and let all 10 get in front. Also, my zipper gets joined at the botom and the “merge” point travels back up the the path. we are all going to sqeeze into one lane anyway. Don’t care where it happens as long as everyone maintains speed. If you expect me to stop my lane so 10 can come from yours we have a problem.
The issue is that in backed up traffic, not zipper merging results in a single lane of cars that takes up twice as much road space as zipper merging.
Perhaps the issue is zipper merging not being taught in drivers ed, idk.
It’s taught, but the concept is counter-intuitive, goes against American etiquette for queuing, and puts all of the risk for getting stuck on the driver doing the correct thing (going all the way down to the merge).
The queue is not the lane closing. The queue is the through-traffic. The people racing to the front of an already full queue ARE NOT ZIPPER MERGING. They’re cutting in line.
The point of a zipper merge is to do it cleanly without affecting others’ speeds as much as possible. Flying to the front of a line is not matching speed, and it’s not merging cleanly.
Then it’s not properly taught. You’re still queuing, and if everyone is taught how to do it correctly and is executing it correctly, it works well and everybody gets their turn. Hell, you don’t even need everybody to do it correctly, just most people.
If people don’t fully understand the concept enough to recognize that they are still in line and get their turn, then they were not taught the concept correctly or are not smart enough to be driving a vehicle.
If things are flowing properly and maintaining proper space both lanes would be combining at the end where the closed lane cuts off, they would be moving at the same speed by necessity. No one would have space to zoom to the end because it would be occupied.
If everyone stayed in the lane that’s about to close, your scenario wouldn’t happen. The issue isn’t the people going all the way to the end to merge, it’s everyone merging beforehand that causes the backup.
Traffic waves in that scenario come from people merging. If everyone merged at the end, there would be a small, consistent slowdown there. One small wave being reinforced over time. But, because everyone in the lane about to close merges as soon as they can, there are dozens of waves being generated all at once, which causes the stop-and-go effect. And as the backup becomes worse, more people start merging earlier, causing even more waves and more backup.
