Traffic signal

[traffic light guy]

I found a decommissioned Eagle signal in Norristown:

Decommissioned 8-inch Eagle flatback signal by thesignalman, on Flickr

Decommissioned eagle signal by thesignalman, on Flickr

Decommissioned 8" Eagle signal by thesignalman, on Flickr

[ErmineNotyours]

Non-standard arrow on an eight inch head in Edmonds, Washington.  From a distance it just looks like a horizontal line, like a transit signal.

[traffic light guy]

Non-standard arrow on an eight inch head in Edmonds, Washington.  From a distance it just looks like a horizontal line, like a transit signal.

That looks like an MUTCD voilation

[fwydriver405]

Non-standard arrow on an eight inch head in Edmonds, Washington.  From a distance it just looks like a horizontal line, like a transit signal.

Is the turn leading P/P, lagging P/P, or split phase? I am also going to assume that the arrow isn't bimodal...

[jakeroot]

That looks like an MUTCD voilation

There's a few others in WA (here, here to name a few)...that's not to say they're compliant now, but they must have been acceptable at one point.

Non-standard arrow on an eight inch head in Edmonds, Washington.  From a distance it just looks like a horizontal line, like a transit signal.

Is the turn leading P/P, lagging P/P, or split phase? I am also going to assume that the arrow isn't bimodal...

I believe it's split-phased.

There are actually four 8-inch green arrows at this intersection, two for each direction (both with left-pointing arrows).

[Brandon]

Non-standard arrow on an eight inch head in Edmonds, Washington.  From a distance it just looks like a horizontal line, like a transit signal.

That looks like an MUTCD violation

Only a violation of modern standards.  I'd say this is an old signal kept in decent condition.

[jay8g]

There are actually four 8-inch green arrows at this intersection, two for each direction (both with left-pointing arrows).

Bizarrely, it looks like these signals used to have standard (though 8-inch) green arrows and they were changed out at some point in the last few years to these much less legible ones. (Not that the normal ones are particularly legible in 8-inch form either -- I'm quite familiar with that Campus Parkway example, and I always think that those lights look like they're out from a distance...)

[Scott5114]

You guys realize that's a standard Type D arrow, right? Someone flipped to the "signs" chapter of the standards and copied from that instead of the "signals" chapter. Might have been a sign guy getting stuck on signal duty...

[jakeroot]

You guys realize that's a standard Type D arrow, right? Someone flipped to the "signs" chapter of the standards and copied from that instead of the "signals" chapter. Might have been a sign guy getting stuck on signal duty...

Nope! Didn't occur to me for even a second. But that's mostly because I've seen arrows like this before (both U-turn arrows, strangely):

[CJResotko]

does anyone know what brand of traffic light this is
https://goo.gl/maps/ffW4Tfcr9h99LEsU7

Those are Siemens traffic signals.

[jakeroot]

Rather unusual situation. Curious if it's MUTCD compliant?

At this intersection in Tacoma, WA, traffic is permitted to go three directions: straight-on, slight left, and hard left. At the beginning of the phase, there is a protected green arrow for the slight left turn, to coincide with that direction's green movement, but the hard left turn "must yield" (as the slightly-angled green arrow only protects the slight left turn). This is followed by a permissive phase for the slight left (the hard left remaining as fully-permissive).

My question is whether or not it's acceptable to permit this situation. My worries arise because of the green arrow in combination with the "must yield" action for the hard left, and that both movements occur from the same lane.

This signal has been in place for a very long time, as you can tell. All 8-inch incandescent signals, except for the 12-inch signals which are the old round-door Bullseye signals. The bimodal left turn display was recently installed, more than likely to make the signal more compliant with the "two through signals" requirement; formerly, the left signal controlled the left lane, and the right lane was controlled by the green up arrow. The only permissive turn, thus, was the left turn onto Yakima. The slight left was protected only.

Here's a video of the operation:

https://youtu.be/TxW7rb7g5XI

[Revive 755]

Rather unusual situation. Curious if it's MUTCD compliant?

At this intersection in Tacoma, WA, traffic is permitted to go three directions: straight-on, slight left, and hard left. At the beginning of the phase, there is a protected green arrow for the slight left turn, to coincide with that direction's green movement, but the hard left turn "must yield" (as the slightly-angled green arrow only protects the slight left turn). This is followed by a permissive phase for the slight left (the hard left remaining as fully-permissive).

My question is whether or not it's acceptable to permit this situation. My worries arise because of the green arrow in combination with the "must yield" action for the hard left, and that both movements occur from the same lane.

IMHO, I would go with MUTCD compliant, given the angle of the green arrow - but I would love to see FHWA's take on it.  It would be similar to many cases where a left turn would protected, but a U-turn would have to yield.

Hopefully the next edition of the MUTCD will have more discussion of this and other non-standard intersections (such as how to do signal warrants for this intersection and/or those with five or more legs).

[jeffandnicole]

Rather unusual situation. Curious if it's MUTCD compliant?

At this intersection in Tacoma, WA, traffic is permitted to go three directions: straight-on, slight left, and hard left. At the beginning of the phase, there is a protected green arrow for the slight left turn, to coincide with that direction's green movement, but the hard left turn "must yield" (as the slightly-angled green arrow only protects the slight left turn). This is followed by a permissive phase for the slight left (the hard left remaining as fully-permissive).

My question is whether or not it's acceptable to permit this situation. My worries arise because of the green arrow in combination with the "must yield" action for the hard left, and that both movements occur from the same lane.

IMHO, I would go with MUTCD compliant, given the angle of the green arrow - but I would love to see FHWA's take on it.  It would be similar to many cases where a left turn would protected, but a U-turn would have to yield.

Hopefully the next edition of the MUTCD will have more discussion of this and other non-standard intersections (such as how to do signal warrants for this intersection and/or those with five or more legs).

The biggest issue I see is that the green arrow is for traffic in the left lane...but the left lane is also forced to yield for the sharper left turn. That's usually a No-no.  If an arrow is above the lane that lane is exclusively to be used for that movement.

[fwydriver405]

Rather unusual situation. Curious if it's MUTCD compliant?

At this intersection in Tacoma, WA, traffic is permitted to go three directions: straight-on, slight left, and hard left. At the beginning of the phase, there is a protected green arrow for the slight left turn, to coincide with that direction's green movement, but the hard left turn "must yield" (as the slightly-angled green arrow only protects the slight left turn). This is followed by a permissive phase for the slight left (the hard left remaining as fully-permissive).

My question is whether or not it's acceptable to permit this situation. My worries arise because of the green arrow in combination with the "must yield" action for the hard left, and that both movements occur from the same lane.

This signal has been in place for a very long time, as you can tell. All 8-inch incandescent signals, except for the 12-inch signals which are the old round-door Bullseye signals. The bimodal left turn display was recently installed, more than likely to make the signal more compliant with the "two through signals" requirement; formerly, the left signal controlled the left lane, and the right lane was controlled by the green up arrow. The only permissive turn, thus, was the left turn onto Yakima. The slight left was protected only.

Here's a video of the operation:

https://youtu.be/TxW7rb7g5XI

Is this intersection in Nashua NH similar to the one mentioned above:
NH 130 and 101 A

I thought that the 4-section signal is not allowed in exclusive left turn lanes because circular indications were not permitted in in exclusive left turn lanes... the movement from 130 E does not allow left turns, and the movement from 101 E does not allow right turns.

Here's the phasing (order is from top to bottom):

[jakeroot]

IMHO, I would go with MUTCD compliant, given the angle of the green arrow - but I would love to see FHWA's take on it.  It would be similar to many cases where a left turn would protected, but a U-turn would have to yield.

Hopefully the next edition of the MUTCD will have more discussion of this and other non-standard intersections (such as how to do signal warrants for this intersection and/or those with five or more legs).

Interesting that you'd bring up the U-turn comparison. I've never actually seen one of those "U-turn Must Yield" signs in real life. Signalized U-turns in WA never have overlapping right turn green arrows, though I know they exist elsewhere. I've always assumed they weren't MUTCD compliant, honestly. But you're absolutely right, that this situation is very similar!

I too would appreciate further guidance on this kind of situation. I have some ideas of my own, but no idea how the FHWA may approach it.

The biggest issue I see is that the green arrow is for traffic in the left lane...but the left lane is also forced to yield for the sharper left turn. That's usually a No-no.  If an arrow is above the lane that lane is exclusively to be used for that movement.

That was my thought. Even if the green arrow was for a different movement, it's still one lane. The green arrow seems misleading. The hard-left is a fairly uncommon turn, but it's nonetheless permitted, and I feel the current signal is not ideal. It's better than the old setup but still seems problematic.

Is this intersection in Nashua NH similar to the one mentioned above:
NH 130 and 101 A

I thought that the 4-section signal is not allowed in exclusive left turn lanes because circular indications were not permitted in in exclusive left turn lanes... the movement from 130 E does not allow left turns, and the movement from 101 E does not allow right turns.

Here's the phasing (order is from top to bottom):
[snipped]

Fairly similar! Big difference being two possible left turns in my example, versus one in yours. My example would probably be identical, with the constant green up arrow, if not for the road from the left (N Yakima Ave). Oh crap, I didn't see that road on the hard left (Bennett St). Very similar! Although it appears that the "protected" phasing holds traffic along NH-130, whereas mine has them go at the same time, with traffic going to my equivalent of "Bennett St" is required to yield, despite the green arrow.

[kphoger]

Technically, all traffic facing a green arrow of any sort is still required to yield.

Section 4D.04 Meaning of Vehicular Signal Indications

Standard:

03 The following meanings shall be given to highway traffic signal indications for vehicles and pedestrians:

2.  Vehicular traffic facing a GREEN ARROW signal indication, displayed alone or in combination with another signal indication, is permitted to cautiously enter the intersection only to make the movement indicated by such arrow, or such other movement as is permitted by other signal indications displayed at the same time.

Such vehicular traffic, including vehicles turning right or left or making a U-turn movement, shall yield the right-of-way to:

Pedestrians lawfully within an associated crosswalk, and
Other vehicles lawfully within the intersection.

[jakeroot]

Technically, all traffic facing a green arrow of any sort is still required to yield.

But is traffic destined for the hard left (in my example) considered "such vehicular traffic" under Chapter 4D? Since although their lane has a green arrow, their movement does not.

[kphoger]

Technically, all traffic facing a green arrow of any sort is still required to yield.

But is traffic destined for the hard left (in my example) considered "such vehicular traffic" under Chapter 4D? Since although their lane has a green arrow, their movement does not.

Well, yes.  As I read it, "such vehicular traffic" refers to "vehicular traffic facing a GREEN ARROW signal indication".  And, as such, they are required to "yield the right-of-way to ... other vehicles lawfully within the intersection."  However, none of that is relevant.  The same rule applies to circular green signals, besides the fact that the traffic you really have to worry about are the ones not yet within the intersection.

[SignBridge]

The key phrase in that MUTCD section is "lawfully" within the intersection or crosswalk. So for instance a pedestrian crossing against a red light or a "don't walk" signal would be unlawfully in the crosswalk and drivers would not be required to yield to them. At least that's my understanding.

The theory of the green turning arrow is that it's an exclusive right-of-way. The signal will not clear any movement that conflicts with the green turning arrow, and that includes pedestrian signals.

[Revive 755]

Interesting that you'd bring up the U-turn comparison. I've never actually seen one of those "U-turn Must Yield" signs in real life. Signalized U-turns in WA never have overlapping right turn green arrows, though I know they exist elsewhere. I've always assumed they weren't MUTCD compliant, honestly. But you're absolutely right, that this situation is very similar!

The 'U-Turn Yield to Right Turn' signs show up in Illinois every now and then.  Example at the IL 31/Charles J. Miller Road intersection near McHenry.

[roadfro]

Rather unusual situation. Curious if it's MUTCD compliant?

At this intersection in Tacoma, WA, traffic is permitted to go three directions: straight-on, slight left, and hard left. At the beginning of the phase, there is a protected green arrow for the slight left turn, to coincide with that direction's green movement, but the hard left turn "must yield" (as the slightly-angled green arrow only protects the slight left turn). This is followed by a permissive phase for the slight left (the hard left remaining as fully-permissive).

My question is whether or not it's acceptable to permit this situation. My worries arise because of the green arrow in combination with the "must yield" action for the hard left, and that both movements occur from the same lane.

IMHO, I would go with MUTCD compliant, given the angle of the green arrow - but I would love to see FHWA's take on it.  It would be similar to many cases where a left turn would protected, but a U-turn would have to yield.

Hopefully the next edition of the MUTCD will have more discussion of this and other non-standard intersections (such as how to do signal warrants for this intersection and/or those with five or more legs).

I'm not 100% sure it's compliant, but also not 100% sure that it isn't. It's one of those situations that sufficiently unusual that you can't come up with a "typical" scenario to put into the MUTCD. It also doesn't help that both left turns are made from the same lane, so you can't separate the operation.

The only way I can think of to improve this and also remove the ambiguity with the sign is to use a modified doghouse. In the left column would be FYA for the hard left, and the right column would display green and FYA arrows for the slight left. (This solution would need to introduce an additional through signal to maintain compliance with the MUTCD standard about two through signals.)

[fwydriver405]

Rather unusual situation. Curious if it's MUTCD compliant?

At this intersection in Tacoma, WA, traffic is permitted to go three directions: straight-on, slight left, and hard left. At the beginning of the phase, there is a protected green arrow for the slight left turn, to coincide with that direction's green movement, but the hard left turn "must yield" (as the slightly-angled green arrow only protects the slight left turn). This is followed by a permissive phase for the slight left (the hard left remaining as fully-permissive).

My question is whether or not it's acceptable to permit this situation. My worries arise because of the green arrow in combination with the "must yield" action for the hard left, and that both movements occur from the same lane.

IMHO, I would go with MUTCD compliant, given the angle of the green arrow - but I would love to see FHWA's take on it.  It would be similar to many cases where a left turn would protected, but a U-turn would have to yield.

Hopefully the next edition of the MUTCD will have more discussion of this and other non-standard intersections (such as how to do signal warrants for this intersection and/or those with five or more legs).

I'm not 100% sure it's compliant, but also not 100% sure that it isn't. It's one of those situations that sufficiently unusual that you can't come up with a "typical" scenario to put into the MUTCD. It also doesn't help that both left turns are made from the same lane, so you can't separate the operation.

The only way I can think of to improve this and also remove the ambiguity with the sign is to use a modified doghouse. In the left column would be FYA for the hard left, and the right column would display green and FYA arrows for the slight left. (This solution would need to introduce an additional through signal to maintain compliance with the MUTCD standard about two through signals.)

So for both the Nashua, NH and Tacoma, WA intersections, something like this?



The topmost section is a red ball, the upper yellow sections are for clearance, and the bottom green/yellow bimodal section is for the protected and permissive movements. The "LEFT TURN SIGNAL" sign is only there because in the Nashua example, the left turn from WB NH-101A to WB NH-130 cannot proceed when the opposing (eastbound NH-101A) traffic has a green, which results in a red ball for the left turn onto 130, and straight-arrow for traffic proceeding on 101A west.

[jeffandnicole]

Rather unusual situation. Curious if it's MUTCD compliant?

At this intersection in Tacoma, WA, traffic is permitted to go three directions: straight-on, slight left, and hard left. At the beginning of the phase, there is a protected green arrow for the slight left turn, to coincide with that direction's green movement, but the hard left turn "must yield" (as the slightly-angled green arrow only protects the slight left turn). This is followed by a permissive phase for the slight left (the hard left remaining as fully-permissive).

My question is whether or not it's acceptable to permit this situation. My worries arise because of the green arrow in combination with the "must yield" action for the hard left, and that both movements occur from the same lane.

IMHO, I would go with MUTCD compliant, given the angle of the green arrow - but I would love to see FHWA's take on it.  It would be similar to many cases where a left turn would protected, but a U-turn would have to yield.

Hopefully the next edition of the MUTCD will have more discussion of this and other non-standard intersections (such as how to do signal warrants for this intersection and/or those with five or more legs).

I'm not 100% sure it's compliant, but also not 100% sure that it isn't. It's one of those situations that sufficiently unusual that you can't come up with a "typical" scenario to put into the MUTCD. It also doesn't help that both left turns are made from the same lane, so you can't separate the operation.

The only way I can think of to improve this and also remove the ambiguity with the sign is to use a modified doghouse. In the left column would be FYA for the hard left, and the right column would display green and FYA arrows for the slight left. (This solution would need to introduce an additional through signal to maintain compliance with the MUTCD standard about two through signals.)

So for both the Nashua, NH and Tacoma, WA intersections, something like this?



The topmost section is a red ball, the upper yellow sections are for clearance, and the bottom green/yellow bimodal section is for the protected and permissive movements. The "LEFT TURN SIGNAL" sign is only there because in the Nashua example, the left turn from WB NH-101A to WB NH-130 cannot proceed when the opposing (eastbound NH-101A) traffic has a green, which results in a red ball for the left turn onto 130, and straight-arrow for traffic proceeding on 101A west.

You'll have a single signal for each movement, when 2 signals per movement are preferred.

Really, this is an issue regarding lane assignments or phasing.  If you take the right lane and make that the straight/soft left movement, and make the left lane the hard left movement, then you can dedicate the signal for the left lane for the hard left, and dedicate the signals for the right lane for the other two movements, then everything is MUTCD kosher.  Likewise, if you add an additional phase where traffic from the soft left has it's own phase, then traffic in the left lane pictured above can turn left hard or soft without interference.

Yet, there are issues with the above.  If traffic volumes warrant the two lanes, there may be too much traffic going straight and making the soft left to stuff in one lane.  How do you show the signal for the hard left - a solid green arrow indicates they have priority, which isn't true.  This is where a FYA works well, due to the unusual intersection layout.   Also, it may feel unnatural to make that soft left from the right lane, confusing motorists.  Or, if you add an additional cycle, then that creates more waiting time for traffic, adding potential delay and congestion to the intersection.

Intersections like this are tough to deal with, and any option presented has downsides.

[Revive 755]

So for both the Nashua, NH and Tacoma, WA intersections, something like this?





The topmost section is a red ball, the upper yellow sections are for clearance, and the bottom green/yellow bimodal section is for the protected and permissive movements. The "LEFT TURN SIGNAL" sign is only there because in the Nashua example, the left turn from WB NH-101A to WB NH-130 cannot proceed when the opposing (eastbound NH-101A) traffic has a green, which results in a red ball for the left turn onto 130, and straight-arrow for traffic proceeding on 101A west.

Technically those would not be MUTCD compliant either:

A U-turn arrow signal indication pointing to the left shall not be used in a signal face that also contains a left-turn arrow signal indication. A U-turn arrow signal indication pointing to the right shall not be used in a signal face that also contains a right-turn arrow signal indication.

It's kind of a no-win intersection with the current MUTCD.  I would certainly like the above section to be revisited in the next edition so both a green U-turn arrow and green left could be used in areas with a decent number of U-turns and no conflicting right turn overlaps.

[jakeroot]

^^^
For my intersection, it would not be correct to use a U-turn arrow. A regular hard-left arrow would suffice: