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Right on Red Arrow

Started by doogie1303, May 30, 2016, 09:30:01 AM

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jakeroot

Quote from: NoGoodNamesAvailable on October 11, 2018, 04:51:25 PM
Quote from: jeffandnicole on October 11, 2018, 01:40:52 PM
Across the street, there is a bad MUTCD violation though...Here's an example of a shared thru/right turn lane with a turning signal arrow directly above the lane: https://goo.gl/maps/hRFt2Jq2Aft .  This seems to be a holdover from when the lane was truly a right turn only lane, as seen in this 2009 GSV: https://goo.gl/maps/obz3stv18xm . When converted to a shared lane the signal should've been modified but wasn't.  Even more oddly: The next intersection continues the shared thru/right turn lane with another non-MUTCD permitted signal.  And that lane instantly becomes a street parking lane, so the lane shouldn't have thru access at that point to begin with!

Which paragraph(s) does this violate?

Yeah, I'm not sure this is technically a violation of the MUTCD. It's a tough situation due the rail lines, but since the rail lines always have ROW (or usually do, in most cities), they have no choice but to fully protect all movements going across that road.

There is a seldom-used option that permits both a red arrow and red orb. When the light turns green, the red orb stays lit for whatever direction to protect another movement. Spokane, WA has this for a pedestrian crossing: https://goo.gl/kD6L5X. It would be a good option for these right turns.

The only "improvement" that could be made would be to make the right lanes exclusive right turn lanes, but I don't see how that helps the situation, besides reducing the chance that a driver might get stuck behind someone turning.


roadfro



Quote from: jakeroot on October 11, 2018, 05:07:16 PM
Quote from: NoGoodNamesAvailable on October 11, 2018, 04:51:25 PM
Quote from: jeffandnicole on October 11, 2018, 01:40:52 PM
Across the street, there is a bad MUTCD violation though...Here's an example of a shared thru/right turn lane with a turning signal arrow directly above the lane: https://goo.gl/maps/hRFt2Jq2Aft .  This seems to be a holdover from when the lane was truly a right turn only lane, as seen in this 2009 GSV: https://goo.gl/maps/obz3stv18xm . When converted to a shared lane the signal should've been modified but wasn't.  Even more oddly: The next intersection continues the shared thru/right turn lane with another non-MUTCD permitted signal.  And that lane instantly becomes a street parking lane, so the lane shouldn't have thru access at that point to begin with!

Which paragraph(s) does this violate?

Yeah, I'm not sure this is technically a violation of the MUTCD. It's a tough situation due the rail lines, but since the rail lines always have ROW (or usually do, in most cities), they have no choice but to fully protect all movements going across that road.

There is a seldom-used option that permits both a red arrow and red orb. When the light turns green, the red orb stays lit for whatever direction to protect another movement. Spokane, WA has this for a pedestrian crossing: https://goo.gl/kD6L5X. It would be a good option for these right turns.

The only "improvement" that could be made would be to make the right lanes exclusive right turn lanes, but I don't see how that helps the situation, besides reducing the chance that a driver might get stuck behind someone turning.

Actually, it's a violation, at least in the 2009 MUTCD...

Quote
Section 4D.21 Signal Indications for Right-Turn Movements — General
...
Standard:
...
05 A protected only mode right-turn movement that does not begin and terminate at the same time as the adjacent through movement shall not be provided on an approach unless an exclusive right-turn lane exists.

Probably the kosher solution here is to use an activated blank out "no right turn" symbol sign when the train is approaching.
Roadfro - AARoads Pacific Southwest moderator since 2010, Nevada roadgeek since 1983.

ErmineNotyours

Quote from: jakeroot on October 27, 2017, 12:25:52 AM
Hmm. More common than I realized. Unless another PNW user knows of one that I can't think of, I am certain that no electronic prohibition signs exist in my area for purposes other than railways or crosswalks. Still seems a bit odd.

There's this one in Renton, where traffic coming down hill from around the corner may not be visible to cars turning right.  https://goo.gl/maps/m5zfhW5grEk

jakeroot

Quote from: ErmineNotyours on October 13, 2018, 11:45:52 PM
Quote from: jakeroot on October 27, 2017, 12:25:52 AM
Hmm. More common than I realized. Unless another PNW user knows of one that I can't think of, I am certain that no electronic prohibition signs exist in my area for purposes other than railways or crosswalks. Still seems a bit odd.

There's this one in Renton, where traffic coming down hill from around the corner may not be visible to cars turning right.  https://goo.gl/maps/m5zfhW5grEk

Very nice. I appreciate them not immediately using a NTOR sign. What does it say when activated?

MNHighwayMan

It's definitely a "No Right Turn" sign. You can kind of see a faint outline of the symbol in this image here.

1995hoo

Found this today exiting the Fairfax County Parkway (VA-286) to Telegraph Road. Virginia normally doesn't allow right on red arrow, but this is an interesting exception. I've used that exit before (not often, though, just because of where it is) but I had not noticed this sign. Don't know whether there are any other places like this. (The arrows were flashing red when I took the picture. I guess they were dark when I snapped it.)

"You know, you never have a guaranteed spot until you have a spot guaranteed."
—Olaf Kolzig, as quoted in the Washington Times on March 28, 2003,
commenting on the Capitals clinching a playoff spot.

"That sounded stupid, didn't it?"
—Kolzig, to the same reporter a few seconds later.

kphoger

Quote from: 1995hoo on October 14, 2018, 04:10:34 PM
Found this today exiting the Fairfax County Parkway (VA-286) to Telegraph Road. Virginia normally doesn't allow right on red arrow, but this is an interesting exception. I've used that exit before (not often, though, just because of where it is) but I had not noticed this sign. Don't know whether there are any other places like this. (The arrows were flashing red when I took the picture. I guess they were dark when I snapped it.)



Gotta love having to read nine words in order to know what to do.
Keep right except to pass.  Yes.  You.
Visit scenic Orleans County, NY!
Male pronouns, please.

Quote from: Philip K. DickIf you can control the meaning of words, you can control the people who must use them.

plain

Quote from: 1995hoo on October 14, 2018, 04:10:34 PM
Found this today exiting the Fairfax County Parkway (VA-286) to Telegraph Road. Virginia normally doesn't allow right on red arrow, but this is an interesting exception. I've used that exit before (not often, though, just because of where it is) but I had not noticed this sign. Don't know whether there are any other places like this. (The arrows were flashing red when I took the picture. I guess they were dark when I snapped it.)



Definitely the first time I've heard of flashing red arrows in Virginia. Do they always flash during the red cycle?
Newark born, Richmond bred

1995hoo

#233
I don't know simply because I don't use that exit often enough. Also, when I do use that exit I've always turned left (as I did today–I was going from my parents' house to Wegmans and I just didn't feel like taking the Beltway), so I'm usually not paying attention to the right-turn lights (if I can even see them, depending on which lane I'm in). Today I was in the right lane of two left-turn lanes and I had a fairly long wait for a green, which is why I noticed it this time.
"You know, you never have a guaranteed spot until you have a spot guaranteed."
—Olaf Kolzig, as quoted in the Washington Times on March 28, 2003,
commenting on the Capitals clinching a playoff spot.

"That sounded stupid, didn't it?"
—Kolzig, to the same reporter a few seconds later.

jakeroot

Quote from: kphoger on October 14, 2018, 04:57:17 PM
Gotta love having to read nine words in order to know what to do.

It's definitely self-explanatory, but even as implemented, it's a massive improvement compared to 99% of VA's double right turns, which inevitably ban RTOR from the left lane.

Quote from: plain on October 14, 2018, 04:59:57 PM
Definitely the first time I've heard of flashing red arrows in Virginia. Do they always flash during the red cycle?

Flashing red arrows are pretty rare, period (except in Maryland). I suspect it goes to solid red following the green cycle, before switching to flashing red after a couple moments. Similar to an FYA cycle.

Roadsguy

Quote from: jakeroot on October 14, 2018, 05:22:50 PM
Quote from: kphoger on October 14, 2018, 04:57:17 PM
Gotta love having to read nine words in order to know what to do.

It's definitely self-explanatory, but even as implemented, it's a massive improvement compared to 99% of VA's double right turns, which inevitably ban RTOR from the left lane.

Despite the two signals, it's actually only a single lane, unless they widened it since the Street View was taken (which 1995hoo didn't mention having been done).
Mileage-based exit numbering implies the existence of mileage-cringe exit numbering.

1995hoo

Quote from: Roadsguy on October 14, 2018, 08:52:29 PM
Quote from: jakeroot on October 14, 2018, 05:22:50 PM
Quote from: kphoger on October 14, 2018, 04:57:17 PM
Gotta love having to read nine words in order to know what to do.

It's definitely self-explanatory, but even as implemented, it's a massive improvement compared to 99% of VA's double right turns, which inevitably ban RTOR from the left lane.

Despite the two signals, it's actually only a single lane, unless they widened it since the Street View was taken (which 1995hoo didn't mention having been done).

When I went through there today, there were two right-turn lanes and two left-turn lanes. I haven't looked at Street View (including your link) to see if it's been revised over the years. Too lazy and more interested in the can of DC Brau that's sitting over here.
"You know, you never have a guaranteed spot until you have a spot guaranteed."
—Olaf Kolzig, as quoted in the Washington Times on March 28, 2003,
commenting on the Capitals clinching a playoff spot.

"That sounded stupid, didn't it?"
—Kolzig, to the same reporter a few seconds later.

Roadsguy

Quote from: 1995hoo on October 14, 2018, 09:15:53 PM
Quote from: Roadsguy on October 14, 2018, 08:52:29 PM
Quote from: jakeroot on October 14, 2018, 05:22:50 PM
Quote from: kphoger on October 14, 2018, 04:57:17 PM
Gotta love having to read nine words in order to know what to do.

It's definitely self-explanatory, but even as implemented, it's a massive improvement compared to 99% of VA's double right turns, which inevitably ban RTOR from the left lane.

Despite the two signals, it's actually only a single lane, unless they widened it since the Street View was taken (which 1995hoo didn't mention having been done).

When I went through there today, there were two right-turn lanes and two left-turn lanes. I haven't looked at Street View (including your link) to see if it's been revised over the years. Too lazy and more interested in the can of DC Brau that's sitting over here.

Huh, interesting. The pavement was definitely there for two lanes, though even in the old Street View before the flashing red arrow, there were two signals.
Mileage-based exit numbering implies the existence of mileage-cringe exit numbering.

ErmineNotyours

Quote from: jakeroot on October 14, 2018, 12:40:00 AM
Quote from: ErmineNotyours on October 13, 2018, 11:45:52 PM
Quote from: jakeroot on October 27, 2017, 12:25:52 AM
Hmm. More common than I realized. Unless another PNW user knows of one that I can't think of, I am certain that no electronic prohibition signs exist in my area for purposes other than railways or crosswalks. Still seems a bit odd.

There's this one in Renton, where traffic coming down hill from around the corner may not be visible to cars turning right.  https://goo.gl/maps/m5zfhW5grEk

Very nice. I appreciate them not immediately using a NTOR sign. What does it say when activated?

It has a symbolic no right turn prohibition, like this one.  In this intersection in Kirkland the prohibition comes on not on the walk sign, but when opposing left turning traffic is in the protected phase.  It turns off when it is in the permissive phase.

Blankable right on red restriction by Arthur Allen, on Flickr

Roadsguy

Quote from: ErmineNotyours on October 14, 2018, 10:41:46 PM
Quote from: jakeroot on October 14, 2018, 12:40:00 AM
Quote from: ErmineNotyours on October 13, 2018, 11:45:52 PM
Quote from: jakeroot on October 27, 2017, 12:25:52 AM
Hmm. More common than I realized. Unless another PNW user knows of one that I can't think of, I am certain that no electronic prohibition signs exist in my area for purposes other than railways or crosswalks. Still seems a bit odd.

There's this one in Renton, where traffic coming down hill from around the corner may not be visible to cars turning right.  https://goo.gl/maps/m5zfhW5grEk

Very nice. I appreciate them not immediately using a NTOR sign. What does it say when activated?

It has a symbolic no right turn prohibition, like this one.  In this intersection in Kirkland the prohibition comes on not on the walk sign, but when opposing left turning traffic is in the protected phase.  It turns off when it is in the permissive phase.

Blankable right on red restriction by Arthur Allen, on Flickr

Seems like it'd make more sense for the LED display to say No Turn On Red.
Mileage-based exit numbering implies the existence of mileage-cringe exit numbering.

1995hoo

Quote from: Roadsguy on October 14, 2018, 10:27:17 PM
Quote from: 1995hoo on October 14, 2018, 09:15:53 PM
Quote from: Roadsguy on October 14, 2018, 08:52:29 PM
Quote from: jakeroot on October 14, 2018, 05:22:50 PM
Quote from: kphoger on October 14, 2018, 04:57:17 PM
Gotta love having to read nine words in order to know what to do.

It's definitely self-explanatory, but even as implemented, it's a massive improvement compared to 99% of VA's double right turns, which inevitably ban RTOR from the left lane.

Despite the two signals, it's actually only a single lane, unless they widened it since the Street View was taken (which 1995hoo didn't mention having been done).

When I went through there today, there were two right-turn lanes and two left-turn lanes. I haven't looked at Street View (including your link) to see if it's been revised over the years. Too lazy and more interested in the can of DC Brau that's sitting over here.

Huh, interesting. The pavement was definitely there for two lanes, though even in the old Street View before the flashing red arrow, there were two signals.

You know, upon reflection I think I should amend my comment to say the people turning right had formed two lanes, so I assumed there were two. That's not always a valid assumption, of course! I did not look over to see the actual pavement markings.
"You know, you never have a guaranteed spot until you have a spot guaranteed."
—Olaf Kolzig, as quoted in the Washington Times on March 28, 2003,
commenting on the Capitals clinching a playoff spot.

"That sounded stupid, didn't it?"
—Kolzig, to the same reporter a few seconds later.

US 89

Quote from: Roadsguy on October 15, 2018, 08:21:12 AM
Quote from: ErmineNotyours on October 14, 2018, 10:41:46 PM
Quote from: jakeroot on October 14, 2018, 12:40:00 AM
Quote from: ErmineNotyours on October 13, 2018, 11:45:52 PM
Quote from: jakeroot on October 27, 2017, 12:25:52 AM
Hmm. More common than I realized. Unless another PNW user knows of one that I can't think of, I am certain that no electronic prohibition signs exist in my area for purposes other than railways or crosswalks. Still seems a bit odd.

There's this one in Renton, where traffic coming down hill from around the corner may not be visible to cars turning right.  https://goo.gl/maps/m5zfhW5grEk

Very nice. I appreciate them not immediately using a NTOR sign. What does it say when activated?

It has a symbolic no right turn prohibition, like this one.  In this intersection in Kirkland the prohibition comes on not on the walk sign, but when opposing left turning traffic is in the protected phase.  It turns off when it is in the permissive phase.

Blankable right on red restriction by Arthur Allen, on Flickr

Seems like it'd make more sense for the LED display to say No Turn On Red.

Why? Symbol signs tend to be more easily readable than text-based signs, which can get a little bit wordy.

Here's an example of a text "No Right Turn on Red" electronic sign. It turns off only when either the green or yellow arrow in the doghouse is on. Oddly, it doesn't turn off if only the actual through light is green, and not the arrow (which only happens if someone activates the pedestrian crossing on the right). While that's technically correct, I think it just invites confusion to leave the "NRTOR" sign up while right turns are allowed on a green light. If they could reprogram the sign to turn off on any green light or arrow, it would almost certainly work better as a symbol No Right Turn sign.

That Washington example is very similar to this one in Utah: the electronic No Right Turn sign is only on when the opposing left turn light is green. Right turns are allowed while traffic coming off the freeway has a green light (and of course, with the eastbound green light).

jeffandnicole

Quote from: US 89 on October 15, 2018, 09:45:07 AM

Here's an example of a text "No Right Turn on Red" electronic sign. It turns off only when either the green or yellow arrow in the doghouse is on. Oddly, it doesn't turn off if only the actual through light is green, and not the arrow (which only happens if someone activates the pedestrian crossing on the right). While that's technically correct, I think it just invites confusion to leave the "NRTOR" sign up while right turns are allowed on a green light. If they could reprogram the sign to turn off on any green light or arrow, it would almost certainly work better as a symbol No Right Turn sign.


Why did they even bother with the electronic sign? Panning the GSV to the right there's a traditional NTOR sign posted, so regardless if the electronic sign is on or off, no one is permitted to turn on red anyway.

hotdogPi

I believe that turning on a solid red arrow should not be allowed, and flashing red arrows should be the primary way to distinguish between whether RTOR is allowed or not, instead of using signs.
Clinched

Traveled, plus
US 13, 44, 50
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NH 27, 111A(E); CA 133; NY 366; GA 42, 140; FL A1A, 7; CT 32; VT 2A, 5A; PA 3, 51, 60, QC 162, 165, 263; 🇬🇧A100, A3211, A3213, A3215, A4222; 🇫🇷95 D316

plain

Quote from: jakeroot on October 14, 2018, 05:22:50 PM
Quote from: plain on October 14, 2018, 04:59:57 PM
Definitely the first time I've heard of flashing red arrows in Virginia. Do they always flash during the red cycle?

Flashing red arrows are pretty rare, period (except in Maryland). I suspect it goes to solid red following the green cycle, before switching to flashing red after a couple moments. Similar to an FYA cycle.

Yeah the only other state I've seen them in is Delaware and I don't think they even have them there anymore.
Newark born, Richmond bred

Brandon

#245
Quote from: Roadsguy on October 15, 2018, 08:21:12 AM
Quote from: ErmineNotyours on October 14, 2018, 10:41:46 PM
Quote from: jakeroot on October 14, 2018, 12:40:00 AM
Quote from: ErmineNotyours on October 13, 2018, 11:45:52 PM
Quote from: jakeroot on October 27, 2017, 12:25:52 AM
Hmm. More common than I realized. Unless another PNW user knows of one that I can't think of, I am certain that no electronic prohibition signs exist in my area for purposes other than railways or crosswalks. Still seems a bit odd.

There's this one in Renton, where traffic coming down hill from around the corner may not be visible to cars turning right.  https://goo.gl/maps/m5zfhW5grEk

Very nice. I appreciate them not immediately using a NTOR sign. What does it say when activated?

It has a symbolic no right turn prohibition, like this one.  In this intersection in Kirkland the prohibition comes on not on the walk sign, but when opposing left turning traffic is in the protected phase.  It turns off when it is in the permissive phase.

Blankable right on red restriction by Arthur Allen, on Flickr

Seems like it'd make more sense for the LED display to say No Turn On Red.

Michigan seems to use them extensively where they light up for while the opposing left turn is protected.
https://goo.gl/maps/K4dHu6f7MJG2
"If you think this has a happy ending, you haven't been paying attention." - Ramsay Bolton, "Game of Thrones"

"Symbolic of his struggle against reality." - Reg, "Monty Python's Life of Brian"

jakeroot

Quote from: ErmineNotyours on October 14, 2018, 10:41:46 PM
Quote from: jakeroot on October 14, 2018, 12:40:00 AM
Quote from: ErmineNotyours on October 13, 2018, 11:45:52 PM
Quote from: jakeroot on October 27, 2017, 12:25:52 AM
Hmm. More common than I realized. Unless another PNW user knows of one that I can't think of, I am certain that no electronic prohibition signs exist in my area for purposes other than railways or crosswalks. Still seems a bit odd.

There's this one in Renton, where traffic coming down hill from around the corner may not be visible to cars turning right.  https://goo.gl/maps/m5zfhW5grEk

Very nice. I appreciate them not immediately using a NTOR sign. What does it say when activated?

It has a symbolic no right turn prohibition, like this one.  In this intersection in Kirkland the prohibition comes on not on the walk sign, but when opposing left turning traffic is in the protected phase.  It turns off when it is in the permissive phase.

https://farm2.staticflickr.com/1928/30388024057_c1d885be56_c.jpg

That's my favorite intersection in Kirkland! (For undisclosed reasons). Never noticed that sign before. Kind of odd they'd bother with that sign at all, given the total lack of a crosswalk. It's only purpose would be for what it's being used for (NTOR during oncoming left turn), but I can't figure out why that phase needs such total exclusivity. If there's cars coming, no one's going to turn on red anyways.

US 89

Quote from: jeffandnicole on October 15, 2018, 10:10:32 AM
Quote from: US 89 on October 15, 2018, 09:45:07 AM

Here's an example of a text "No Right Turn on Red" electronic sign. It turns off only when either the green or yellow arrow in the doghouse is on. Oddly, it doesn't turn off if only the actual through light is green, and not the arrow (which only happens if someone activates the pedestrian crossing on the right). While that's technically correct, I think it just invites confusion to leave the "NRTOR" sign up while right turns are allowed on a green light. If they could reprogram the sign to turn off on any green light or arrow, it would almost certainly work better as a symbol No Right Turn sign.


Why did they even bother with the electronic sign? Panning the GSV to the right there's a traditional NTOR sign posted, so regardless if the electronic sign is on or off, no one is permitted to turn on red anyway.

That brings up a good point, what do you do if you’re looking at a NTOR sign and a green arrow at the same time? Even if the electronic sign didn’t turn off for the arrows, it’s clearly obvious that you’re intended to go on a red light/green arrow combination. I wonder what the MUTCD says about setups like this.

Looking at it more, that’s a really weird intersection in more ways than that. Looking at this GSV frame, it appears that there’s an extended green to allow eastbound traffic to turn left. That’s something I’d never seen or heard of in Utah before, despite the fact that I’ve been through that intersection more times than I can count.




Quote from: jakeroot on October 15, 2018, 01:57:32 PM
That's my favorite intersection in Kirkland! (For undisclosed reasons). Never noticed that sign before. Kind of odd they'd bother with that sign at all, given the total lack of a crosswalk. It's only purpose would be for what it's being used for (NTOR during oncoming left turn), but I can't figure out why that phase needs such total exclusivity. If there's cars coming, no one's going to turn on red anyways.

I disagree. Yes you aren’t supposed to, but the stupidity level of many drivers is quite high. I’ve had several close calls with idiots who made a right turn on red in front of me, not realizing I had a green arrow. This specific intersection may have had a high enough crash rate from this that they just put up the sign and called it good.

jakeroot

#248
Quote from: US 89 on October 15, 2018, 02:08:30 PM
Quote from: jakeroot on October 15, 2018, 01:57:32 PM
That's my favorite intersection in Kirkland! (For undisclosed reasons). Never noticed that sign before. Kind of odd they'd bother with that sign at all, given the total lack of a crosswalk. It's only purpose would be for what it's being used for (NTOR during oncoming left turn), but I can't figure out why that phase needs such total exclusivity. If there's cars coming, no one's going to turn on red anyways.

I disagree. Yes you aren't supposed to, but the stupidity level of many drivers is quite high. I've had several close calls with idiots who made a right turn on red in front of me, not realizing I had a green arrow. This specific intersection may have had a high enough crash rate from this that they just put up the sign and called it good.

Thinking again, it might be due to capacity. The oncoming left turn, logically, has less opportunity to turn, compared to the opposing right turn (the movement with the electronic no-right-turn sign). To reduce the chance that drivers turning right would fill up the ramp meters for the ramps to 405 as they would be constantly turning (more or less), they limit turns on red when oncoming traffic is turning to reduce the opportunity for that right turn to saturate the capacity of the ramps.

WA barely bans turning on red except in cases of reduced visibility, but one example I'm familiar with is the eastbound Valley Ave right turn onto southbound WA-161 in Puyallup. Yes, it's a double right turn, but that's not the reason for the NTOR restriction. There is a freeway entrance just after the right turn, and it's a popular destination for this right turn. But the other movements at the intersection also like entering the freeway at this point. To avoid the right turn constantly going on red and using all available capacity on 161, they deny turns on red, so the oncoming left turn and the perpendicular straight movement have more of an opportunity to go.




Quote from: US 89 on October 15, 2018, 02:08:30 PM
That brings up a good point, what do you do if you're looking at a NTOR sign and a green arrow at the same time? Even if the electronic sign didn't turn off for the arrows, it's clearly obvious that you're intended to go on a red light/green arrow combination. I wonder what the MUTCD says about setups like this.

Right turns on green arrows are not considered a violation of NTOR. Such combinations are very common in PA.

mrsman

Quote from: jakeroot on October 15, 2018, 03:10:16 PM
Quote from: US 89 on October 15, 2018, 02:08:30 PM
Quote from: jakeroot on October 15, 2018, 01:57:32 PM
That's my favorite intersection in Kirkland! (For undisclosed reasons). Never noticed that sign before. Kind of odd they'd bother with that sign at all, given the total lack of a crosswalk. It's only purpose would be for what it's being used for (NTOR during oncoming left turn), but I can't figure out why that phase needs such total exclusivity. If there's cars coming, no one's going to turn on red anyways.

I disagree. Yes you aren't supposed to, but the stupidity level of many drivers is quite high. I've had several close calls with idiots who made a right turn on red in front of me, not realizing I had a green arrow. This specific intersection may have had a high enough crash rate from this that they just put up the sign and called it good.

Thinking again, it might be due to capacity. The oncoming left turn, logically, has less opportunity to turn, compared to the opposing right turn (the movement with the electronic no-right-turn sign). To reduce the chance that drivers turning right would fill up the ramp meters for the ramps to 405 as they would be constantly turning (more or less), they limit turns on red when oncoming traffic is turning to reduce the opportunity for that right turn to saturate the capacity of the ramps.

WA barely bans turning on red except in cases of reduced visibility, but one example I'm familiar with is the eastbound Valley Ave right turn onto southbound WA-161 in Puyallup. Yes, it's a double right turn, but that's not the reason for the NTOR restriction. There is a freeway entrance just after the right turn, and it's a popular destination for this right turn. But the other movements at the intersection also like entering the freeway at this point. To avoid the right turn constantly going on red and using all available capacity on 161, they deny turns on red, so the oncoming left turn and the perpendicular straight movement have more of an opportunity to go.



The NTOR also provides pedestrians a safe opportunity to cross the right turn lanes.  This shouldn't be a big deal, since it seems that right turners here have a lot of time to make their turn, both the time that EB Valley faces green as well as the time that NB Meridian makes the left turn to WB Valley. 



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