Idea for different speed limits per lane

[hotdogPi]

The freeway would have the left lane with a sign saying "For passing only", the second to left lane "60-70 MPH", the second to right lane "50-70 MPH", and the right lane "40-65 MPH".

Would this be possible? Would the wording have to change to be enforceable?

As an added possibility, these signs could change during traffic. The left lane would say "Left lane 10¢ per mile EZPASS", and the other lanes would say "Free lane", as well as the second to right lane saying "X minutes to [next freeway]" and the right lane saying "X minutes to next exit". The signs can also say "CLOSED" during construction of those lanes.

[corco]

It would work if speed limits reflected actual driving speeds. As it is, if the speed limit is 65 and everybody goes 75, speed limits per lane would likely make things worse since you'd ostensibly get a bigger ticket for driving in the "slow" lane, since 75 in a 55 is a bigger ticket than 75 in a 65.

[froggie]

Probably easier to do (because there's already precedent) is restricting traffic that cannot maintain a given speed from using the far left lane.  I want to say I've seen this somewhere in the Northeast (can't remember where), but it also exists on the Like Like Hwy on Oahu approaching the Wilson Tunnels from K-Bay (iirc, traffic under 40 MPH restricted to the right lane).

[jakeroot]

I think a speed limit for each lane is a bit too much regulation. Studies have proven over and over again that people go the speed they feel is reasonable. With that in mind, perhaps we ought to start looking into de-restricting speeds along certain stretches of roadway. Speed limits have been the same since Interstates were invented (and have in fact decreased since creation, i.e. Penn State Turnpike), so we should look into changing the policy. I hate the term "speed limit" and "maximum speed" anyway.

On restricting slower traffic to the right lanes, we could just take the UK's approach:

Motorways MUST NOT be used by pedestrians, holders of provisional motorcycle or car licences, riders of motorcycles under 50 cc, cyclists, horse riders, certain slow-moving vehicles and those carrying oversized loads (except by special permission), agricultural vehicles, and powered wheelchairs/powered mobility scooters (see Rules 36 to 46 inclusive)

I'm sure we already have laws like those, however.

[vdeane]

Blame NMSL.  We still haven't escaped its legacy.

[Dr Frankenstein]

Doesn't Italy have something like that?

[Scott5114]

I want to say this was tried in California, and was found either unconstitutional or violated the MUTCD, and the scheme was cancelled, resulting in a curious assembly where there are multiple speed limit signs, one per lane, all now reading the same speed.

[briantroutman]

Apparently, it at least was tried in Washington.



I thought I had seen variable per-lane limits on German Autobahns (with the illuminated numbers above each lane), but every picture I could find showed the same speed across the board. It definitely has been done in Italy, though.

[Scott5114]

I think the 60 in that Washington photo is over a HOV lane, which is a somewhat different scenario.

[TEG24601]

I think the 60 in that Washington photo is over a HOV lane, which is a somewhat different scenario.

True enough, but in theory, if there was a backup on one of the ramps, that was then flowing into the freeway, they could have the left general purpose lane at 60 as well.


This might work, but would likely work better as having posted minimum speeds for each lane, so those going 55 in the left lane could be ticketed for impeding traffic.  Of course, that will only really be useful when they stop using speed limits as a money-making enterprise and return to the 85/15 (or 80/20) speed law.

[Kniwt]

I want to say this was tried in California, and was found either unconstitutional or violated the MUTCD, and the scheme was cancelled, resulting in a curious assembly where there are multiple speed limit signs, one per lane, all now reading the same speed.

The study was of variable minimum speed limits per lane back in 1966 and was found not to work, at least back then:
https://archive.org/stream/califvol4546orniahighwa6667calirich#page/38/mode/2up

[jakeroot]

Apparently, it at least was tried in Washington.

Actually, it works pretty well. I drive through Seattle regularly, and they're pretty helpful. They don't necessarily regulate speed, more than they just let you know the speed up ahead, so you don't "panic brake" and cause another accident. And of course, as Scott5114 said, the far left lane is HOV, and ***typically*** they move faster, hence the 60. They also have this "Active Traffic Management" system on I-90 crossing Lake Washington.

[Kacie Jane]

They also have this "Active Traffic Management" system on I-90 crossing Lake Washington.

And on 520, where due to construction, there's not currently any HOV lanes west of 405. It's surely far more rare than the HOV lane on 5 or 90 having a different speed, but I swear at least once or twice I've seen them out the two lanes at different speeds.

[JoePCool14]

That has to be super expensive!

[jakeroot]

That has to be super expensive!

According to WSDOT:

The I-5 Active Traffic Management project is funded as part of WSDOT's Alaskan Way Viaduct and Seawall Replacement project.

The same page also says it costs $101.197 million to install.

It's also worth mentioning that it isn't always on:

[1995hoo]

I'd worry about going too much faster in the left HOV lane than heavy traffic in the adjacent lane regardless of variable speed limits, especially if the traffic in the lane to my right is heavy and slow. I'd be afraid of someone pulling out into my lane suddenly (legally or not). We have some left-lane HOV facilities around here, without the variable speed limits shown above, and even in the rare event the HOV lane is clear enough to move at full speed, if the lane to my right is crawling at 10 mph I'm not too likely to do 55 in the HOV. Feels too dangerous. If there were buffer space or a physical barrier, I'd feel differently about it.

Regarding the OP's suggestion that the left lane have a higher speed limit coupled with a toll, we have something slightly similar to that on I-495 in Virginia. The two left lanes are HO/T lanes with a 65-mph speed limit, while the four "free" lanes have a 55-mph limit. It's not quite the same thing the OP suggests because there is a barrier (plastic bollards) separating the HO/T lanes from the "free" lanes. Hence why I used the phrase "slightly similar."

[jakeroot]

Regarding the OP's suggestion that the left lane have a higher speed limit coupled with a toll, we have something slightly similar to that on I-495 in Virginia. The two left lanes are HO/T lanes with a 65-mph speed limit, while the four "free" lanes have a 55-mph limit. It's not quite the same thing the OP suggests because there is a barrier (plastic bollards) separating the HO/T lanes from the "free" lanes. Hence why I used the phrase "slightly similar."

I love the HO/T lanes along the 495 in Virginia. They are really pushing you all to use them, aren't they? I hope my inquiry isn't far off topic, but I haven't met anyone yet who has used them. From the perspective of a civil engineering student, the whole project was quite the feat.

[1995hoo]

Regarding the OP's suggestion that the left lane have a higher speed limit coupled with a toll, we have something slightly similar to that on I-495 in Virginia. The two left lanes are HO/T lanes with a 65-mph speed limit, while the four "free" lanes have a 55-mph limit. It's not quite the same thing the OP suggests because there is a barrier (plastic bollards) separating the HO/T lanes from the "free" lanes. Hence why I used the phrase "slightly similar."

I love the HO/T lanes along the 495 in Virginia. They are really pushing you all to use them, aren't they? I hope my inquiry isn't far off topic, but I haven't met anyone yet who has used them. From the perspective of a civil engineering student, the whole project was quite the feat.

I use them fairly frequently, in part because I often go to Falls Church for business and the HO/T exit at US-29 (which has no equivalent from the general-purpose lanes) speeds my trip big-time, especially on the way home at rush hour when I-66 inside the Beltway is off-limits due to HOV. Plus, since I'm self-employed I can write off the toll on Schedule C at tax time.

I love the lanes. I don't always use them, especially because if I go to visit my parents in Fairfax it makes no sense (first exit is too far out of the way since they live off Route 236 near Guinea Road and the first HO/T exit is another three miles to the north). But the way I see it is, non-HO/T traffic has the same number of lanes as before, so there are four new lanes you can use if you like, but if you don't want to use them or can't afford to use them you aren't losing anything. The other HO/T project on I-95, which involves converting existing HOV lanes that are open to everyone outside rush hours (except for trucks at the southern end due to a weigh station), is a very different beast and I'm not sure what I think there.

But anyway, that's getting off-topic. To return to the tolling question, one "objection" some people raised to the I-495 project was that they feared the tolling equipment could not be trusted to read E-ZPass transponders only from HO/T lane users. They feared that people passing by in the left lane of the general-purpose lanes might be incorrectly charged. I think it's pretty clear that hasn't happened, as I'm absolutely certain the local media would have been in a frenzy if it had!

[froggie]

I'd worry about going too much faster in the left HOV lane than heavy traffic in the adjacent lane regardless of variable speed limits, especially if the traffic in the lane to my right is heavy and slow. I'd be afraid of someone pulling out into my lane suddenly (legally or not).

Speaking from admittedly-limited experience, they're a lot better about not crossing the double-white line in Seattle than they are in the DC area...

[Kacie Jane]

I'd worry about going too much faster in the left HOV lane than heavy traffic in the adjacent lane regardless of variable speed limits, especially if the traffic in the lane to my right is heavy and slow. I'd be afraid of someone pulling out into my lane suddenly (legally or not).

Speaking from admittedly-limited experience, they're a lot better about not crossing the double-white line in Seattle than they are in the DC area...

But the double-white line is only* for HOT lanes, which are only on SR 167 at the moment, which doesn't have variable speed limits.

(*There are a small handful of places where a regular HOV lane has double "do not cross" lines, but only in the vicinity of HOV on-ramps, only for short distances, and coincidentally, also outside the variable speed zones.)

[KEK Inc.]

Washington usually makes it pretty clear not to cross double white lines, but they're not really common in the state. 
http://goo.gl/maps/fzuyf

North of Ventura County, there's no HOV lanes that you can't merge in and out of in the West Coast.

[1995hoo]

Washington usually makes it pretty clear not to cross double white lines, but they're not really common in the state. 
http://goo.gl/maps/fzuyf

....

That is MUCH more prominent and easy to read than the dinky little signs VDOT posted on I-66 (not that it'd matter, people would still ignore them). They're small enough that I haven't gotten a good picture yet.

What's weird about our double white lines is that the lanes they border are not 24/7 HOV lanes. Outside rush hour, they operate as the regular left lane, but it's still illegal to cross the double white lines (which are located only where the HOV lane passes through interchanges, although one of those interchanges is quite long due to a C/D road system).

[froggie]

But the double-white line is only* for HOT lanes, which are only on SR 167 at the moment, which doesn't have variable speed limits.

Thought I remembered a couple sets of double-white line on the I-5 HOV lanes, both south of downtown (where the above picture was taken), and also north near the I-405 interchange.

[jakeroot]

But the double-white line is only* for HOT lanes, which are only on SR 167 at the moment, which doesn't have variable speed limits.

Thought I remembered a couple sets of double-white line on the I-5 HOV lanes, both south of downtown (where the above picture was taken), and also north near the I-405 interchange.

I-5 does not presently have any HOT lanes, though they are in the books if the 167 is extended.

[KEK Inc.]

But the double-white line is only* for HOT lanes, which are only on SR 167 at the moment, which doesn't have variable speed limits.

Thought I remembered a couple sets of double-white line on the I-5 HOV lanes, both south of downtown (where the above picture was taken), and also north near the I-405 interchange.

And again, Washington doesn't restrict lane changes for HOV.