Slip lanes with stop signs

[PHLBOS]

^^
A ramp meter might be more desirable in these locations, if the merging issues occur primarily during rush hour.

At present, I don't believe NJDOT, NJTA (NJ Turnpike & GSP) and/or SJTA (AC Expressway) has/uses any on their roadways.

[kphoger]

On an intersection in Mexico posted by kphoger in another thread: https://goo.gl/maps/o8HULPQXedF2

The ALTO sign is a bit ahead of a slip lane by a signal.

That seems like odd placement for the sign. I hope they don't intend for traffic to stop at that point. Nevermind stopping at all.

My friend, if weird placement of stop signs is something that bothers you, then please do not drive in Mexico.

[jakeroot]

My friend, if weird placement of stop signs is something that bothers you, then please do not drive in Mexico.

Point taken.

Are there any roundabouts in Mexico with yield signs? Seems like they all have stop signs, from what I've seen.

[kphoger]

Are there any roundabouts in Mexico with yield signs? Seems like they all have stop signs, from what I've seen.

Not sure.  I've only driven through a handful of traffic circles in Mexico and, as I recall, they all were either uncontrolled or had stop signs on some but not all of the approaches (essentially designating a through-route).

[jakeroot]

So this is fucked.

The off-ramp from the eastbound Boeing Freeway (Hwy 526) to Evergreen Way in Everett, WA has a double right turn: one via a slip lane, another via the intersection (for traffic turning left immediately to the right). The right turn at the intersection is, as you might imagine, signalized. But the right turn via the slip lane has a stop sign. This means that traffic turning right with a green light can proceed without stopping, but traffic via the slip lane must stop...over, and over, and over. Ridiculous.

https://goo.gl/maps/bv6DREFexGH7qK686

[Amtrakprod]

So this is fucked.

The off-ramp from the eastbound Boeing Freeway (Hwy 526) to Evergreen Way in Everett, WA has a double right turn: one via a slip lane, another via the intersection (for traffic turning left immediately to the right). The right turn at the intersection is, as you might imagine, signalized. But the right turn via the slip lane has a stop sign. This means that traffic turning right with a green light can proceed without stopping, but traffic via the slip lane must stop...over, and over, and over. Ridiculous.

https://goo.gl/maps/bv6DREFexGH7qK686

The hell? My god WSDot what were y'all thinking, I'd remove the slip lane tbh.


iPhone

[MNHighwayMan]

I'd remove the slip lane tbh.

No. You re-stripe it to eliminate the movement through the signal, and replace the stop sign with a yield sign (or perhaps just remove it entirely).

[jeffandnicole]

Just after that turn is this odd side.  So they don't mind if you just sit around in the grass and weeds prior to this sign?    https://goo.gl/maps/UXShAXU59vqoom6ZA

[webny99]

If we're including on-ramps, then one example I know is the EB on-ramp for Highway 58 from Pine St in Thorold, ON. The merge is short (especially for Ontario), but there's okay visibility leading up to the merge. I'm not sure how I feel about this one.
https://goo.gl/maps/3j7H9aDP3yE2

Plenty of room for a proper merge. That goes into the "silly" bin.

Just seeing this now.. I actually use that ramp with some frequency. The problem is that, because of the tunnel, there's no shoulder or any extended margin for error if something goes off the rails. I personally would be fine with a regular merge, or even a yield sign, but I can see why they might not trust the competence of the average driver.

[1995hoo]

I'd remove the slip lane tbh.

No. You re-stripe it to eliminate the movement through the signal, and replace the stop sign with a yield sign (or perhaps just remove it entirely).

You don't eliminate the movement through the signal because it's needed to allow for proper access to the left-turn lane. In the screenshot above, the Jeep Cherokee (or similar) beyond the white van is waiting in a left-turn-only lane. There's at least one more vehicle behind the Jeep. If the minivan driver wanted to turn left, he'd have to stop in a thru lane and then try to cut the line (that's what people around here would do!), so the proper way to do it is to turn right at the light so you're at the end of the line waiting to turn left.

I suspect the stop sign is there because people not wanting to go to the turn lane will turn right at the light when it's green (I would, if I knew there were a stop sign!), such that having a "Yield" sign might result in too many crashes? I sort of wonder whether the slip lane is there for times when the left-turn lane around the corner is full and people wanting to access it are unable to turn right, so they provide an alternate movement? But there's really only room for one vehicle to the left of the pork chop island anyway, so who knows how helpful that is.

[MNHighwayMan]

You don't eliminate the movement through the signal because it's needed to allow for proper access to the left-turn lane. In the screenshot above, the Jeep Cherokee (or similar) beyond the white van is waiting in a left-turn-only lane. There's at least one more vehicle behind the Jeep. If the minivan driver wanted to turn left, he'd have to stop in a thru lane and then try to cut the line (that's what people around here would do!), so the proper way to do it is to turn right at the light so you're at the end of the line waiting to turn left.

Huh? There's a dedicated left-turn lane, a straight-through/left turn option lane, and the weird right-turn lane. How does the right-turn lane affect the left-turn lane two lanes away? All I was suggesting was making the right-turn lane only use the slip lane.

[1995hoo]

You don't eliminate the movement through the signal because it's needed to allow for proper access to the left-turn lane. In the screenshot above, the Jeep Cherokee (or similar) beyond the white van is waiting in a left-turn-only lane. There's at least one more vehicle behind the Jeep. If the minivan driver wanted to turn left, he'd have to stop in a thru lane and then try to cut the line (that's what people around here would do!), so the proper way to do it is to turn right at the light so you're at the end of the line waiting to turn left.

Huh? There's a dedicated left-turn lane, a straight-through/left turn option lane, and the weird right-turn lane. How does the right-turn lane affect the left-turn lane two lanes away? All I was suggesting was making the right-turn lane only use the slip lane.

I'm talking about access to the left-turn lane around the corner–the one you might want to reach AFTER you turn right. Not the left-turn lanes on the ramp. The slip lane doesn't provide proper access to the turn lane on the other street.

[MNHighwayMan]

I'm talking about access to the left-turn lane around the corner–the one you might want to reach AFTER you turn right. Not the left-turn lanes on the ramp. The slip lane doesn't provide proper access to the turn lane on the other street.

Ooh, okay. That makes much more sense. I didn't see that.

[1995hoo]

I'm talking about access to the left-turn lane around the corner–the one you might want to reach AFTER you turn right. Not the left-turn lanes on the ramp. The slip lane doesn't provide proper access to the turn lane on the other street.

Ooh, okay. That makes much more sense. I didn't see that.

I didn't see it at first either until I looked at Street View, although jakeroot did mention it in the original post about that spot (reply #57 in this thread). Once I saw it on Street View, the separate turn lane via the signal made more sense.

[jakeroot]

Jesus, my link got a fair amount of traction.

I would say the easiest fix would just be to replace the right turn with a yield sign. Ideally, both turns would have a signal, but it's fine as-is (minus the STOP sign).

Now that I'm thinking about it from a technical standpoint, right turns (and left turns) are required to "follow the curb" (RCW 46.61.290) but the law does allow exceptions, such as when markings dictate a different maneuver. That's not the case here. If someone turned right from the left-most right turn lane, directly into the right lane, would traffic using the stop sign be required to yield to the other right turn lane?

[ErmineNotyours]

You don't eliminate the movement through the signal because it's needed to allow for proper access to the left-turn lane. In the screenshot above, the Jeep Cherokee (or similar) beyond the white van is waiting in a left-turn-only lane. There's at least one more vehicle behind the Jeep. If the minivan driver wanted to turn left, he'd have to stop in a thru lane and then try to cut the line (that's what people around here would do!), so the proper way to do it is to turn right at the light so you're at the end of the line waiting to turn left.

I suspect the stop sign is there because people not wanting to go to the turn lane will turn right at the light when it's green (I would, if I knew there were a stop sign!), such that having a "Yield" sign might result in too many crashes? I sort of wonder whether the slip lane is there for times when the left-turn lane around the corner is full and people wanting to access it are unable to turn right, so they provide an alternate movement? But there's really only room for one vehicle to the left of the pork chop island anyway, so who knows how helpful that is.

One alternative is to put in a small curb/divider (whatever they're called) to keep motorists from cutting into the turn lane from the slip lane, like here.

[jakeroot]

One alternative is to put in a small curb/divider (whatever they're called) to keep motorists from cutting into the turn lane from the slip lane, like here.

I got totally thrown by that exact curb/divider a few months ago. I didn't see anything mentioning turning right at the signal for that left turn (and it doesn't seem designed for it either); ended up doing a U-turn, though other cars knew what they were doing and turned at the signal.

[1995hoo]

You don't eliminate the movement through the signal because it's needed to allow for proper access to the left-turn lane. In the screenshot above, the Jeep Cherokee (or similar) beyond the white van is waiting in a left-turn-only lane. There's at least one more vehicle behind the Jeep. If the minivan driver wanted to turn left, he'd have to stop in a thru lane and then try to cut the line (that's what people around here would do!), so the proper way to do it is to turn right at the light so you're at the end of the line waiting to turn left.

I suspect the stop sign is there because people not wanting to go to the turn lane will turn right at the light when it's green (I would, if I knew there were a stop sign!), such that having a "Yield" sign might result in too many crashes? I sort of wonder whether the slip lane is there for times when the left-turn lane around the corner is full and people wanting to access it are unable to turn right, so they provide an alternate movement? But there's really only room for one vehicle to the left of the pork chop island anyway, so who knows how helpful that is.

One alternative is to put in a small curb/divider (whatever they're called) to keep motorists from cutting into the turn lane from the slip lane, like here.

Yup. Here's one local to my area: https://goo.gl/maps/eJ4jjPNymeKwTi1aA  I just assumed for whatever reason the local DOT in jakeroot's link had ruled out that option.

[kphoger]

Now that I'm thinking about it from a technical standpoint, right turns (and left turns) are required to "follow the curb" (RCW 46.61.290) but the law does allow exceptions, such as when markings dictate a different maneuver. That's not the case here. If someone turned right from the left-most right turn lane, directly into the right lane, would traffic using the stop sign be required to yield to the other right turn lane?

Yes.

[jakeroot]

Now that I'm thinking about it from a technical standpoint, right turns (and left turns) are required to "follow the curb" (RCW 46.61.290) but the law does allow exceptions, such as when markings dictate a different maneuver. That's not the case here. If someone turned right from the left-most right turn lane, directly into the right lane, would traffic using the stop sign be required to yield to the other right turn lane?

Yes.

Outrageous. Would never happen IRL but it's funny to think about.

[tolbs17]

We really need some of those here,

https://www.google.com/maps/@35.5909846,-77.3782451,3a,75y,266.09h,88.82t/data=!3m6!1e1!3m4!1sWKrk47xEcghFqLyM-jFiMQ!2e0!7i13312!8i6656

Because look at this. I'm sure slip lanes with stop signs will do for this intersection! This one is clogged.

[ozarkman417]

We really need some of those here,

https://www.google.com/maps/@35.5909846,-77.3782451,3a,75y,266.09h,88.82t/data=!3m6!1e1!3m4!1sWKrk47xEcghFqLyM-jFiMQ!2e0!7i13312!8i6656

Because look at this. I'm sure slip lanes with stop signs will do for this intersection! This one is clogged.

Yield signs would work better on this one.

SM-G965U

[tolbs17]

We really need some of those here,

https://www.google.com/maps/@35.5909846,-77.3782451,3a,75y,266.09h,88.82t/data=!3m6!1e1!3m4!1sWKrk47xEcghFqLyM-jFiMQ!2e0!7i13312!8i6656

Because look at this. I'm sure slip lanes with stop signs will do for this intersection! This one is clogged.

Yield signs would work better on this one.

SM-G965U

Guess so, because some times of the day it's clear, and it's crowded. NCDOT needs to come up with an improvement of that intersection or make it a continuous flow intersection. that intersection carries more than 40,000 vehicles per day.

[jakeroot]

We really need some of those here,

https://www.google.com/maps/@35.5909846,-77.3782451,3a,75y,266.09h,88.82t/data=!3m6!1e1!3m4!1sWKrk47xEcghFqLyM-jFiMQ!2e0!7i13312!8i6656

Because look at this. I'm sure slip lanes with stop signs will do for this intersection! This one is clogged.

Yield signs would work better on this one.

SM-G965U

Guess so, because some times of the day it's clear, and it's crowded. NCDOT needs to come up with an improvement of that intersection or make it a continuous flow intersection. that intersection carries more than 40,000 vehicles per day.

If you have a slip lane, they either need to be signalized (a la Wisconsin practice) or posted with yield signs. The idea is for them to be separate from the main intersection, but drivers can clue-into their priority at the yield point based on the adjacent signal. With stop signs, you'd just have a bunch of drivers who would either ignore the stop sign and turn if safe, or drivers who would turn at the intersection instead, cutting off the slip lane traffic because the stop sign is needlessly slowing traffic down.

With this all in mind, slip lanes are becoming less common. Places like Washington State and British Columbia continue to construct them along expressways and freeway interchanges, but they are becoming less common in urban areas because they A) make intersections quite large, and B) conflict with pedestrians with disabilities, plus drivers a tendency to ignore people waiting to cross the slip lane anyway.

[tolbs17]

We really need some of those here,

https://www.google.com/maps/@35.5909846,-77.3782451,3a,75y,266.09h,88.82t/data=!3m6!1e1!3m4!1sWKrk47xEcghFqLyM-jFiMQ!2e0!7i13312!8i6656

Because look at this. I'm sure slip lanes with stop signs will do for this intersection! This one is clogged.

Yield signs would work better on this one.

SM-G965U

Guess so, because some times of the day it's clear, and it's crowded. NCDOT needs to come up with an improvement of that intersection or make it a continuous flow intersection. that intersection carries more than 40,000 vehicles per day.

If you have a slip lane, they either need to be signalized (a la Wisconsin practice) or posted with yield signs. The idea is for them to be separate from the main intersection, but drivers can clue-into their priority at the yield point based on the adjacent signal. With stop signs, you'd just have a bunch of drivers who would either ignore the stop sign and turn if safe, or drivers who would turn at the intersection instead, cutting off the slip lane traffic because the stop sign is needlessly slowing traffic down.

With this all in mind, slip lanes are becoming less common. Places like Washington State and British Columbia continue to construct them along expressways and freeway interchanges, but they are becoming less common in urban areas because they A) make intersections quite large, and B) conflict with pedestrians with disabilities, plus drivers a tendency to ignore people waiting to cross the slip lane anyway.

That's great to know, because that intersection is a dangerous stretch.