# Left Lane ENDS - 2 Miles Ahead - MERGE RIGHT

**URL:** <https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239>\
**Category:** The BBQ Pit\
**Created:** [May 22, 2002, 3:45am UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239 "2002-05-22T03:45:29Z")\
**Posts on this page:** 20\
**Page:** 4

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**Author:** ![CrankyAsAnOldMan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crankyasanoldman/32/11670_2.png) [@CrankyAsAnOldMan](https://boards.straightdope.com/u/CrankyAsAnOldMan)\
**Post date:** [May 23, 2002, 2:50pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/61 "2002-05-23T14:50:44Z")

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lockfist, did you get hit with any candy? Because that is PRECISELY the stretch of road I was on, Sunday evening, being passed by people on the right.

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**Author:** ![GrizzRich](https://avatars.discourse-cdn.com/v4/letter/g/7ba0ec/32.png) [@GrizzRich](https://boards.straightdope.com/u/GrizzRich)\
**Post date:** [May 23, 2002, 4:03pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/62 "2002-05-23T16:03:31Z")

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> [@](#):
>
> \*Originally posted by zut \*  
> \*\*  
> Astounding. I am completely amazed at the lengths some people will go to justify rude and dangerous behavior. Do you REALLY know why there’s a traffic jam at the merge point? Obviously not. It’s because people like you speed by everyone else, come to the end of the lane, jam on their brakes, and shoehorn themselves in front of some poor unsuspecting sod. Said unsuspecting sod suddenly has his following distance reduced to about 18 inches and has to slam on the binders, making everyone behind him do the same. Wham! Traffic jam.
> 
> The reason construction signs are placed two miles before a merge point is neither to tell you you HAVE to merge immediately, nor (contrary to your antisocial opinion) to allow you to time your swerve at exactly 1.999 miles. It’s to let you know that, sometime in the next couple miles, you need to merge. And, yeah, when exactly one needs to merge is pretty subjective. Some of us can deal with that. Personally, I just try to be considerate of my fellow drivers and not add to the traffic problem. Obviously, you have other priorities.
> 
> I’m surprised that anyone would admit to, let alone take pride in, being a complete asshole. \*\*

…yeah… what zut said!

Besides, if you’re in that much of a hurry, perhaps you should plan your day so that you leave the house sooner!

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**Author:** ![Jodi](https://avatars.discourse-cdn.com/v4/letter/j/7feea3/32.png) [@Jodi](https://boards.straightdope.com/u/Jodi)\
**Post date:** [May 23, 2002, 4:25pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/63 "2002-05-23T16:25:41Z")

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> [@](#):
>
> Jodi, you’re attempts to block a person from merging before you are fruitless at best.

_Au contraire._ They bear full fruit in ensuring that drivers such as you do not merge directly in front of me. Since I can’t run you off the road, it’s the best I can do.

> [@](#):
>
> Furthermore, for every two dozen of you MERGE POLICE, there will be plenty of space a short distance behind you for my vehicle to merge.

Correct. You can merge at will. Any place behind me. Heck, you can merge at some point in front of me, if you can zoom up that far. But you will _not_ be merging directly in front of me. That’s the only part of the scenario I have any control over, and that’s how I choose to control it.

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**Author:** ![Tretiak](https://avatars.discourse-cdn.com/v4/letter/t/a88e57/32.png) [@Tretiak](https://boards.straightdope.com/u/Tretiak)\
**Post date:** [May 23, 2002, 5:20pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/64 "2002-05-23T17:20:18Z")

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I understand how you can show that isfe everyone is nice and all that then mergina t the smae point is most efficient. But take that model and just a little bit of noise to, make one car out of a hundred go a little faster, a little slower. What is interesting is how fast it turns into a fubar situation, becasue it has a cascading effect and then you can see how waiting until the last minute to merge is usually not a good idea becuase the chances of a smooth merge have decreased substantially because it is your last chance. And that then also has a cascading effect, just making the situation worse.

You should always merge when you can do so safely, maintaining your speed and not hindering drivers behind you. Not at the last minute, not right away necessarily, either.

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**Author:** ![wireless](https://avatars.discourse-cdn.com/v4/letter/w/f14d63/32.png) [@wireless](https://boards.straightdope.com/u/wireless)\
**Post date:** [May 23, 2002, 5:28pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/65 "2002-05-23T17:28:24Z")

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Thanks, **Lockfist, Bearflag** , for responding. And for agreeing with me!

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**Author:** ![lezlers](https://avatars.discourse-cdn.com/v4/letter/l/258eb7/32.png) [@lezlers](https://boards.straightdope.com/u/lezlers)\
**Post date:** [May 23, 2002, 6:42pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/66 "2002-05-23T18:42:10Z")

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Lockfist,

Please don’t tell me you’re one of those assholes who cruise in the far left lane on 101 north at the 101/80 split before the Bay Bridge when it’s clear and the lane going towards 80 is backed up and FORCE (I don’t care how polite you SAY you are, when you’re in an empty lane, going into a gridlocked lane, you’re forcing your way in) your way into the middle lane that goes to 80? I was stuck in that lane on Saturday afternoon and watched at least 10 cars zoom past then force their way in to the gridlocked 80 lane. It may not have slowed traffic THAT much because it was gridlocked anyway, but it’s just RUDE.

And a neon yellow mustang? What, you think you’re a schoolbus or something?

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**Author:** ![zut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zut/32/2875_2.png) [@zut](https://boards.straightdope.com/u/zut)\
**Post date:** [May 23, 2002, 7:23pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/67 "2002-05-23T19:23:26Z")

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> [@](#):
>
> \*Originally posted by Lockfist \*  
> **zut** , I really don’t know what you are getting at here. Rude and Obnoxious ? The lane doesn’t not end for 2 miles ! I do not “shoehorn” myself into any oncoming traffic. You wouldn’t realize this busy sitting in an unnecessary traffic jam, but there are PLENTY of cars who leave dozens of feet between them and the car in front. I suppose it is for a variety of reasons – elderly folks, people changing the radio station or dialing their cell phone. Point being, I can easily merge 50 feet before the lane closure and cause absolutely no traffic stoppage whatsoever….

My goodness. I suppose I should have said “rude and obnoxious and oblivious” rather than just “rude and obnoxious”. Of course you don’t cause any traffic stoppage _for you_, it’s the traffic stoppage for the people _behind you_. Sure, you can easily merge into the two-car-length slot in front of the elderly folks, but guess what? They’re gonna hit the brakes because _you_ slipped in out of nowhere. Same goes for the people that look up from their radio tuning to see all bumper in their windshield. And everyone else behind the person you cut in front of has been inconvenienced because of you.

And before you ask, yes, that’s exactly what happens. Every time someone swerves into line at the last minute, a string of tail lights pop on immediately. But you don’t care, do you?

Still, I’m amazed that you can admit to driving on the shoulder _and_ jumping into the slow lane with 50 feet to spare no matter what the traffic conditions _and_ cutting people off by shoehorning yourself into the “dozens of feet” in front of them, yet wonder with a straight face why that irritates people.

Small hint:  
You = inconvenience other people  
People inconvenienced = people peevish  
Making people peevish = rude and obnoxious

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**Author:** ![LordVor](https://avatars.discourse-cdn.com/v4/letter/l/90ced4/32.png) [@LordVor](https://boards.straightdope.com/u/LordVor)\
**Post date:** [May 23, 2002, 7:52pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/68 "2002-05-23T19:52:02Z")

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I’m probably too late into the thread to get many views, but here’s where the late-mergers don’t get it. It’s not about when you merge, it’s about what speed you can merge at.

If you can scream to the end of the merge area and merge at freeway speeds, go ahead and do so. But what happens at the end of the merge area if there isn’t a spot for you to immediately go into? You have to stop. And everybody behind you has to stop. And when somebody does let you in, he has to slow down to 0-5 MPH to let you in. **This is why the lane you’re merging into is going 0-5 MPH in the first place.** And if you’re a semi, or you cut in front of a semi, you’ve just added another minute to the commute of everybody behind you as they’re trapped behind the semi as it tries to get back up to freeway speeds. Multiply your actions by the number of people who repeat them, and you get a real delay.

If everybody would start merging sooner, the chance of merging at a respectible speed would increase, as you’d have more area to do it in, and the total average speed of the cars involved would increase. Your personal speed would drop. Boo hoo.

Lastly, nobody, nobody, **nobody** in the “slow” lane is going 0-5 MPH by choice. They would all rather be going at least 50. They are standing in line to do so, patiently waiting their turn. You, Mr. “I’m gonna go 50 as long as I can” are cutting in front of them in line. There is no real-world example where you should get served before somebody doing a similar thing, unless the store providing the service wishes to go to extrodinary measures to you specifically for some reason. (frequent flyer, express lane at the grocers, etc)

There is no such reason valid for traffic situations.

And there also is a special place in hell for Caltrans, who have put up enough bogus “construction ahead, lane ends in two miles” signs where the lane DOESN’T end in two miles because the construction project was either over months ago or hasn’t started yet has made my first reaction to such signs now be “Yeah, right”.

-lv

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**Author:** ![Lockfist](https://avatars.discourse-cdn.com/v4/letter/l/838e76/32.png) [@Lockfist](https://boards.straightdope.com/u/Lockfist)\
**Post date:** [May 24, 2002, 4:17am UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/69 "2002-05-24T04:17:59Z")

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**mske** , point well taken. I know you won’t believe me but I am a model driver when it comes to allowing others to merge. The car in front of me doesn’t let anyone in ? Well, what do you know, I open up enough room to let two cars in front of me. As to my late-merge techniques I’ll admit that at times I may cause some slow-down of cars behind me but honestly, I am accutley aware of the perception my merge practices have so I am very dilligent to merge at an appropriate time as not to cause any additional congestion.

**kittenblue** , I can do one better for you, my “real” name is the same as a serial killer with 10 movies under his belt 😉 By the way, now I can put a name to the cute girl in the car next to me in the next traffic jam.

**CrankyAsAnOldMan** , Ha ! I was wondering if I would find a person on I-23 Sunday evening. I did pass a lot of cars 😃 You will be happy to know that a rather large red pickup truck forced my speed and merge such that traffic was moving at an orderly pace upon the lane closure. I can’t say I noticed any candy, but – it was a rental after all !

**Jodi** , I’ll have to respect your decision, and from the way you drive I will merge knowing that at least one car in front of is doing their best to make the construction commute that much smoother…

**lezlers** , I know exactly what you are talking about ! However, I approach 80 N from the Bryant St. entrance. I will inform you that if I was taking 101 to 80 N I would NOT cross the white line on the Mission/ Fell exit to try and squeeze back onto the Bridge. In fact, the @ssholes that use that technique are usually blocking my own progress on to Fell St. Regarding the Mustang - I didn’t get the pick the color, but I have a feeling the **Michigan State Police** don’t mind having such an obvious target in the radar scope !

**zut, LordVor** , and everyone else who disagrees with me. Let me just say that I completely understand your point of view. In fact, if more people did know how to merge properly I would have no problem merging early. However, since I know that people \*don’t \* know how this works, I will continue to exploit the weakness to my advantage. Vicious Cycle that it may be…

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**Author:** ![The\_Ryan](https://avatars.discourse-cdn.com/v4/letter/t/7feea3/32.png) [@The\_Ryan](https://boards.straightdope.com/u/The_Ryan)\
**Post date:** [May 24, 2002, 8:57pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/70 "2002-05-24T20:57:03Z")

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[QUOTE]  
\*Originally posted by Billdo \*  
**As someone who has studied traffic engineering,**  
Did you pass any of your classes?

> [@](#):
>
> A key equation in traffic engineering is that volume and speed on a given stretch of highway are inversely proportional. That is to say, the more traffic volume, the lower the speed.

Those two statments mean quite different things.

> [@](#):
>
> In our example, the average speed on the highway might be 60 mph for a volume per lane of 500, and 20 mph for a volume per lane of 1000.

The 500 part is before the 1000 part, right? So if the drivers in the 500 part travel 60 mph while the drivers in the 1000 part travel 20 mph, you don’t have to be a traffic engineer to realize that there’s going to be a massive pile-up.

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**Author:** ![Cheesesteak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cheesesteak/32/3694_2.png) [@Cheesesteak](https://boards.straightdope.com/u/Cheesesteak)\
**Post date:** [May 24, 2002, 9:26pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/71 "2002-05-24T21:26:12Z")

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**The Ryan** I think that is exactly what he meant to say, that when you go from 2 lanes to 1 lane, you can get a pileup regardless of your merging technique. People have been arguing that if drivers were to merge smoothly (instead of at the last minute), there would be no traffic jam, **Billdo** was illustrating that smooth merging has little to do with it, volume alone will cause pileups.

BTW, I always thought that when things were inversely proportional, that meant if one goes up, the other goes down, no? What does your version of inversely proportional mean?

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**Author:** ![The\_Ryan](https://avatars.discourse-cdn.com/v4/letter/t/7feea3/32.png) [@The\_Ryan](https://boards.straightdope.com/u/The_Ryan)\
**Post date:** [May 25, 2002, 12:49am UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/72 "2002-05-25T00:49:56Z")

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> [@](#):
>
> \*Originally posted by Cheesesteak \*  
> \*\ ***The Ryan** I think that is exactly what he meant to say, that when you go from 2 lanes to 1 lane, you can get a pileup regardless of your merging technique.

Uhh… by “pile-up” I meant a traffic acciddent involving many vehicles.

> [@](#):
>
> What does your version of inversely proportional mean?

Their product is equal to a constant.

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**Author:** ![pldennison](https://avatars.discourse-cdn.com/v4/letter/p/9fc29f/32.png) [@pldennison](https://boards.straightdope.com/u/pldennison)\
**Post date:** [May 25, 2002, 1:55am UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/73 "2002-05-25T01:55:53Z")

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> [@](#):
>
> \*Originally posted by The Ryan \*  
> \*\*The 500 part is before the 1000 part, right? So if the drivers in the 500 part travel 60 mph while the drivers in the 1000 part travel 20 mph, you don’t have to be a traffic engineer to realize that there’s going to be a massive pile-up. \*\*

No, you have to be a complete idiot who thinks that the only two available speeds for the car are 60 mph and 20 mph and doesn’t understand that the former can smoothly decelerate to the latter without hitting anything.

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**Author:** ![waterj2](https://avatars.discourse-cdn.com/v4/letter/w/858c86/32.png) [@waterj2](https://boards.straightdope.com/u/waterj2)\
**Post date:** [May 25, 2002, 2:54am UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/74 "2002-05-25T02:54:32Z")

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But that’s not taking **Billdo** ’s words absolutely precisely literally, which is of course how he meant them, because **The Ryan** said so.

As for merging, I just squeeze next to the traffic and pass all the cars on my bike. The only problem is when there isn’t even the 44 or so centimeters my handlebars require. In a car, I’d go for the latest point that I can still find an opening in traffic without causing the person I am merging in front of to have to slow down. This is usually a bit before the last second.

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**Author:** ![Cheesesteak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cheesesteak/32/3694_2.png) [@Cheesesteak](https://boards.straightdope.com/u/Cheesesteak)\
**Post date:** [May 25, 2002, 10:13am UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/75 "2002-05-25T10:13:56Z")

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**The Ryan** Sorry, I thought your “pile-up” reference was in terms of traffic “piling up” behind the merge. It didn’t even cross my mind that you meant a massive accident.

Also still confused as to how “inversely proportional” should be considered “quite different” from **Billdo’s** “the more traffic volume, the lower the speed” statement. Even if **Billdo** meant inversely proportional in the strict mathematical sense, his second statement would be correct, it would only require that the changes in traffic and speed occur in a specific way to force the constant product you mentioned. If **Billdo** meant it in the less strict, general sense, his second statement is fine, and does not require a constant product.

> [@](#):
>
> pro·por·tion·al Pronunciation Key (pr-pôrsh-nl, -pr-)  
> adj.  
> Forming a relationship with other parts or quantities; being in proportion.  
> Properly related in size, degree, or other measurable characteristics; corresponding: Punishment ought to be proportional to the crime.  
> Mathematics. Having the same or a constant ratio.

Obviously, the inverse of this would be a constant product (for the mathematical definition), or just an inverted relationship.

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**Author:** ![LH75](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lh75/32/4438_2.png) [@LH75](https://boards.straightdope.com/u/LH75)\
**Post date:** [May 25, 2002, 3:57pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/76 "2002-05-25T15:57:09Z")

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good morning friends,

as friend **zenith** will attest, the general run of drivers in nebraska are pretty considerate and our traffic is comparitively light.

a couple of years ago, i spent a wonderful week in san juan puerto rico. a beautiful city, about 4 times the population of omaha, the trafiic was intimidating to say the least. 2 miles to a lane ending, warning to merge? forget about it! the way that is handled there is the the lane markers disappear for about a hundred yards, and four lanes become two.

to steal a line from dennis miller: they drive like a kamikazi pilot that has just gotten a dear john letter. shoulders are just traffic lanes. i was waiting patiently in a left turn lane (poorly marked) for a light to change. while i waited for the light, three drivers passed me on the right, turning left in front of us, and two went around the left side. i am sure the traffic laws are regarded as suggestions.

i would move there in a heartbeat. it was beautiful and, when they aren’t behind the wheel, the people were more than friendly. it would take a long time to develop the courage to try rush hour traffic there again.

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**Author:** ![Billdo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/billdo/32/315_2.png) [@Billdo](https://boards.straightdope.com/u/Billdo)\
**Post date:** [May 25, 2002, 9:34pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/77 "2002-05-25T21:34:09Z")

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Yes, **The Ryan** , I passed my transportation engineering course.

As part of my simplification of the analysis, I used the term “inversely proportional” in the more general sense, rather than in a strict mathematical sense. That is to say, when volume increases, average speed decreases (but not necessary in a strictly proportional manner).

The simplification left out a few concepts, and only addressed the condition where traffic flow is below maximum roadway capacity. The problems with early merging are significantly increased when the traffic volume exceeds the highway’s “maximum capacity” with the decreased number of lanes. Where maximum capacity is exceeded, traffic becomes “bumper to bumper” and both traffic volume and speed decline in a chaotic manner.

To make my example more accurate, I need to introduce a few more concepts. I also pulled out a reference work: Transportation Research Board, Highway Capacity Manual, Special Report 209 (1985), chapter 3. I’m afraid that the 1985 Highway Capacity Manual is the latest I have at hand. There has been a revision issued in 1994, and there may have been one since then.

To get really technical, there are actually three major variables at work in Traffic Engineering:

v = rate of flow (volume) in vehicles per hour (vph)  
S = average travel speed in miles per hour (mph)  
D = density in vehicles per mile (vpm)

The basic relationship between these three variables is: v = S x D

The intriguing thing about traffic engineering is that traffic will flow smoothly on a given roadway up to a certain maximum volume, known as the roadway capacity, and after that traffic flow breaks down, and both flow and speed both begin to drop somewhat chaotically. This happens at a density of approximately 67 passenger cars per hour. (This is similar to the concept of laminar and non-laminar flow in fluid dynamics.)

The traffic analyses start with “ideal” conditions and adjust for factors affecting the roadway, including physical highway configuration, vehicle mix, and driver characteristics. “Ideal” conditions are (1) 12-foot minimum lane widths, (2) six-foot minimum lateral clearance between the edges of traffic lanes and nearest roadside/median obstacle, (3) all passenger cars in the traffic stream, and (4) drivers typical of weekday commuters. In addition, these analyses assume (1) good pavement conditions, (2) no traffic incidents, and (3) good weather conditions.

For an “ideal” highway with a 60 mph or 70 mph design speed, the maximum capacity is 2000 passenger cars per hour per lane. In a 70 mph design speed “ideal” highway, the densities, speeds and volumes are as follows (source: Table 3-1, table rounded to nearest 50 vph):

```auto

density speed volume
vpm per lane mph vph per lane

12 60 700
20 57 1100
30 54 1550
42 46 1850
67 30 2000
> 67 * *

* "Highly variable, unstable"

```

Our sample system will again consist of a three mile stretch of highway, with two lanes for the first two miles (mile markers 0 to 2) and one lane for the last mile (mile markers 2 to 3). An illustration follows:

```auto

mile markers:
0 1 2 3
--------------------------------

- - - - - - --------
                       /
----------------------/

```

First, we’ll examine traffic flows below the breakdown volume. For mathematical ease, we’ll assume that the traffic speed/volume relationship per lane is as follows:

750 vph per lane \<–\> 60 mph  
1000 vph per lane \<–\> 57 mph  
1500 vph per lane \<–\> 55 mph  
2000 vph per lane \<–\> 30 mph

(Note that in all of these examples, we’re ignoring the effects of the traffic merge from two lanes to one lane, which should be relatively similar whether the merge occurs at mile marker 0 or mile marker 2. In addition, we’re assuming that the speed/volume relationship is the same for an open one or two lane highway and for a one lane construction zone.)

If the highway is lightly used, when people merge will matter little. For instance, if there are only a total of 1500 cars per hour entering the system, if they wait until mile marker 2 to merge, the speed for the first two miles will be 60 mph (1500 vph over two lanes, or 750 vph per lane), and the speed for the last mile will be 55 mph (1500 vph all in one lane). If they merge at mile marker 0, leaving them all in one lane for the whole system, their speed will be 55 mph throughout. In either event, the whole system can be traversed in a bit more than 3 minutes.

If the highway is moderately used, the effects are more pronounced. If there are 2000 cars per hour entering the system, and they wait until mile marker 2 to merge, the speed for the first two miles will be 57 mph (2000 vph over two lanes or 1000 vph per lane), and the speed for the last mile will be 30 mph (2000 vph all in one lane). If they merge at mile marker 0, leaving them all in one lane for the whole system, their speed will be 30 mph throughout. When they merge at mile marker 2, they traverse the system in approximately 4 minutes (2 miles at 57 mph and 1 mile at 30 mph). If they merge at mile marker 0, however, they will take 6 minutes to traverse the system (3 miles at 30 mph).

Where the traffic exceeds the lane capacity of its most constricted area, the effects will be significant. Because the system simply cannot process more than its maximum capacity, if you try to pack more cars into the system, what was formerly smooth traffic flow will break down, and chaotic “bumper to bumper” traffic will result. In the example above, if more than 2000 vph enter the system, the system will back up.

Though I don’t have time right now to do a full analysis of highway capacity in over-capacity conditions, even where the traffic exceeds capacity it is better to merge at mile marker 2. The beginning of the congestion will occur two miles further down the road, leaving the drivers two more miles to travel at full speed and an additional two miles of two lane roadway to store the backup. In addition, there will only be 1 mile of constricted segment to traverse after merge, rather than 3.

Hope this helps.

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**Author:** ![Typo\_Negative](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/typo_negative/32/484_2.png) [@Typo\_Negative](https://boards.straightdope.com/u/Typo_Negative)\
**Post date:** [May 26, 2002, 10:01am UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/78 "2002-05-26T10:01:04Z")

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> [@](#):
>
> \*Originally posted by Cheesesteak \*  
> \*\ ***The Ryan** I think that is exactly what he meant to say, that when you go from 2 lanes to 1 lane, you can get a pileup regardless of your merging technique. \*\*

I disagree. I think the slowdown is caused by cars in 2 lanes suddenly becoming 1. That is why there’s always a slowdown at freeway interchanges. When the aholes wait till till the last second and force their way in, those already in quite naturally slow down to avoid ending up in the ahole’s back seat.

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**Author:** ![Cheesesteak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cheesesteak/32/3694_2.png) [@Cheesesteak](https://boards.straightdope.com/u/Cheesesteak)\
**Post date:** [May 26, 2002, 12:42pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/79 "2002-05-26T12:42:43Z")

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If traffic is flowing smoothly, I don’t see any reason to wait to the very end of the merge, and would personally merge fairly early. Waiting until the end under those conditions causes the merge to be done in an “emergency” fashion. The driver has no time to pick a good spot to merge, and will cause a disruption. I hate that, bugs me to no end.

When traffic has a major slowdown, the merge at the end doesn’t slow traffic too much because they are already at a crawl. Under those conditions, I don’t see the point of leaving a mile’s worth of empty roadway between myself and the merge, just so I can take my place in the queue. It’s just too damn tempting…

**longhair** you should see the traffic in Brazil. I spent a week down there a few years ago, traffic jams were an unbelievable chaotic mess. Even regular traffic was nuts, you hit a stoplight, and all bets are off. Nobody stays in their lane, people go on the shoulder, the whole bit. I got so used to it, when I got back to the States, I kind of drove like them. Came up to a stoplight, 2 lanes going my way, and a couple of cars waiting. I just cruised up onto the shoulder next to them, waited for the green, and zoomed off! Five seconds later, I said to myself “What were you doing back there???”

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**Author:** ![LH75](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lh75/32/4438_2.png) [@LH75](https://boards.straightdope.com/u/LH75)\
**Post date:** [May 26, 2002, 1:22pm UTC](https://boards.straightdope.com/t/left-lane-ends-2-miles-ahead-merge-right/110239/80 "2002-05-26T13:22:27Z")

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friend cheesesteak,

> [@](#):
>
> Came up to a stoplight, 2 lanes going my way, and a couple of cars waiting. I just cruised up onto the shoulder next to them, waited for the green, and zoomed off! Five seconds later, I said to myself “What were you doing back there???”

we now refer to incidents like that as “normal puerto rico traffic”

driving to the mall the other night, a car ahead of us moved into the curb lane without checking and forced another car into a lilac bush along the road. my wife commented “he must have learned to drive in puerto rico!”

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