Double left turns with permissive phasing

[Amtrakprod]

it also has dallas phasing!

Are we sure? Because it could be split phasing. Dallas phasing can have that appearance, unless Google Street View shows (within the same set of images) a permissive mode, followed by a protected green arrow for only one of the movements. Seeing only one direction with a green arrow (at a typical 5-section display), when the other direction also has a ton of waiting cars, is either caused by one of the directions having a lagging protected green arrow (fully protected left turn), no protected turn at all, or (rarely) the intersection operating protective/permissive most of the time, and split-phased during other times.

Check out the 360 views here. it's not in the split phase phase.

https://www.google.com/maps/@30.2633489,-97.7445113,3a,15y,97.94h,98.25t/data=!3m6!1e1!3m4!1sK-JcQoBYswEgWMahpYmrAQ!2e0!7i13312!8i6656

[jakeroot]

it also has dallas phasing!

Are we sure? Because it could be split phasing. Dallas phasing can have that appearance, unless Google Street View shows (within the same set of images) a permissive mode, followed by a protected green arrow for only one of the movements. Seeing only one direction with a green arrow (at a typical 5-section display), when the other direction also has a ton of waiting cars, is either caused by one of the directions having a lagging protected green arrow (fully protected left turn), no protected turn at all, or (rarely) the intersection operating protective/permissive most of the time, and split-phased during other times.

Check out the 360 views here. it's not in the split phase phase.

https://www.google.com/maps/@30.2633489,-97.7445113,3a,15y,97.94h,98.25t/data=!3m6!1e1!3m4!1sK-JcQoBYswEgWMahpYmrAQ!2e0!7i13312!8i6656

Oh, yeah. You can see it pretty clearly here too. Of course, it's operating that way during the single-left-turn mode.

I did a bit more sleuthing. Look at this image from Sep 2016; if you look at the traffic waiting across from the Street View car, we can see a Chevy Tahoe or Suburban, as well as a 1st-gen Ford Fusion. To our right, we can see a whole load of cars waiting to proceed straight. There's also two guys walking southbound on Congress way off to the left, and a runner going eastbound along Cesar Chavez (behind, left).

Now, jump ahead one click to follow the camera car through the left turn. First, note that westbound Cesar Chavez has a red light while our left turn has a green arrow. The cars that were to our right have set off (you can see most of them well ahead at the next signal or approaching it); the two guys walking are waiting at the corner; the runner has crossed Cesar Chavez by about five car-lengths; there's other stuff too, I'm sure. But what has changed is the oncoming cars: all of them are completely different.

Note that the camera car has not made any progress relative to most of the cars that were originally to the right. This tells me that the Street View vehicle started with a solid green (yield signal), while traffic to its right proceeded off. But by the time the image was taken, the green arrow had activated for our left turn, indicating a lagging green arrow. But there is no yellow trap for one important reason: apparently, when that double left turn was installed, a fourth signal was installed on the mast. It appears that, during some hours, they run the double left turn from the 5-section signals as a protected-only turn, and the two three-section signals (one overhead, one on mast) become the through signals.

That was really hard to explain; I hope it makes some sense.

[Amtrakprod]

it also has dallas phasing!

Are we sure? Because it could be split phasing. Dallas phasing can have that appearance, unless Google Street View shows (within the same set of images) a permissive mode, followed by a protected green arrow for only one of the movements. Seeing only one direction with a green arrow (at a typical 5-section display), when the other direction also has a ton of waiting cars, is either caused by one of the directions having a lagging protected green arrow (fully protected left turn), no protected turn at all, or (rarely) the intersection operating protective/permissive most of the time, and split-phased during other times.

Check out the 360 views here. it's not in the split phase phase.

https://www.google.com/maps/@30.2633489,-97.7445113,3a,15y,97.94h,98.25t/data=!3m6!1e1!3m4!1sK-JcQoBYswEgWMahpYmrAQ!2e0!7i13312!8i6656

Oh, yeah. You can see it pretty clearly here too. Of course, it's operating that way during the single-left-turn mode.

I did a bit more sleuthing. Look at this image from Sep 2016; if you look at the traffic waiting across from the Street View car, we can see a Chevy Tahoe or Suburban, as well as a 1st-gen Ford Fusion. To our right, we can see a whole load of cars waiting to proceed straight. There's also two guys walking southbound on Congress way off to the left, and a runner going eastbound along Cesar Chavez (behind, left).

Now, jump ahead one click to follow the camera car through the left turn. First, note that westbound Cesar Chavez has a red light while our left turn has a green arrow. The cars that were to our right have set off (you can see most of them well ahead at the next signal or approaching it); the two guys walking are waiting at the corner; the runner has crossed Cesar Chavez by about five car-lengths; there's other stuff too, I'm sure. But what has changed is the oncoming cars: all of them are completely different.

Note that the camera car has not made any progress relative to most of the cars that were originally to the right. This tells me that the Street View vehicle started with a solid green (yield signal), while traffic to its right proceeded off. But by the time the image was taken, the green arrow had activated for our left turn, indicating a lagging green arrow. But there is no yellow trap for one important reason: apparently, when that double left turn was installed, a fourth signal was installed on the mast. It appears that, during some hours, they run the double left turn from the 5-section signals as a protected-only turn, and the two three-section signals (one overhead, one on mast) become the through signals.

That was really hard to explain; I hope it makes some sense.

I understand this:
During peak periods, when the lane control lane is a left turn only, it operates in a split phase. During off-peak hours, it uses Dallas phasing and the lane control lane is straight only, to prevent double left turn permissive.

[jakeroot]

I understand this:
During peak periods, when the lane control lane is a left turn only, it operates in a split phase. During off-peak hours, it uses Dallas phasing and the lane control lane is straight only, to prevent double left turn permissive.

Actually, what I'm thinking is that the left turns operate as lead/lag during peak hours, but the double left turn is protected-only during these peak hours. This is evidenced by the extra through signal that was installed; when the two left turn signals are red, there are still two through signals for the straight-ahead movement along Cesar Chavez.

[Amtrakprod]

I still think the Lead-Lag is midday because of the sun's position:
https://www.google.com/maps/@30.2633489,-97.7445113,3a,66.7y,210.93h,129.85t/data=!3m6!1e1!3m4!1sK-JcQoBYswEgWMahpYmrAQ!2e0!7i13312!8i6656

[Amtrakprod]

https://www.google.com/maps/@30.2633509,-97.7445162,3a,25.4y,318.47h,96.02t/data=!3m7!1e1!3m5!1svZNy0kdk4G8v9WqEOfk0-g!2e0!5s20170101T000000!7i13312!8i6656
Woah! The cycle isn't split phased! It's Protected left!

[jakeroot]

https://www.google.com/maps/@30.2633509,-97.7445162,3a,25.4y,318.47h,96.02t/data=!3m7!1e1!3m5!1svZNy0kdk4G8v9WqEOfk0-g!2e0!5s20170101T000000!7i13312!8i6656
Woah! The cycle isn't split phased! It's Protected left!

Right, right. That's what I was saying:

what I'm thinking is that the left turns operate as lead/lag during peak hours, but the double left turn is protected-only during these peak hours. This is evidenced by the extra through signal that was installed; when the two left turn signals are red, there are still two through signals for the straight-ahead movement along Cesar Chavez.

[stevashe]

While this is your thread Jake, I would prefer that examples like this not be included.  There are probably many intersections out there with some form of double left that doesn't need to yield to vehicular traffic, but yields to pedestrians.  Basically, T-intersections or one-way streets.  But these are really different from situations where you would yield to vehicles in the way that you approach them. 

If there is no opposing traffic, in what sense are you making a permissive turn?  The turn is functionally equivalent to a right turn, as you have to watch for pedestrians, but during green ball phase you have no vehicles to watch out for.

In those situations, the vast majority will be turns with green ball (or perhaps FYA to highlight yielding to peds).  Very few of this situation would involve a red arrow, protected only turn (such as very high pedestrian volume).

No, it's good. You make a legitimate point. I'm sure they're far more common than regular dual-permissive left turns. I don't personally know of any that work this way in WA (all my local examples are from British Columbia), which is why I was initially fine with their inclusion. But all things considered, traffic control-wise, it's certainly not as interesting as a dual permissive left across traffic.

Nevertheless, if someone wanted to share a location where a traffic light works in this fashion, I'm not sure where else they'd post about it. Another reason I was fine with it. If I ran into one in Washington, I might have considered posting it here with the caveat that it's not a true "double permissive left turn" in the sense that there is no "oncoming" vehicular traffic.

Bit late to reply on this, but given a strict reading of the thread's title, a left turn against a crosswalk displaying the walk signal would count. While I agree that it is quite a different in operation due to not needing to yield to opposing traffic, in Traffic Engineering terms this is still considered a permitted/permissive left turn. In fact, the "normal" right turn you mention is also considered a permitted right. (A protected right with a green arrow requires both crosswalks to be Don't Walk and is usually shown with the opposing protected left.)

[Amtrakprod]

While this is your thread Jake, I would prefer that examples like this not be included.  There are probably many intersections out there with some form of double left that doesn't need to yield to vehicular traffic, but yields to pedestrians.  Basically, T-intersections or one-way streets.  But these are really different from situations where you would yield to vehicles in the way that you approach them. 

If there is no opposing traffic, in what sense are you making a permissive turn?  The turn is functionally equivalent to a right turn, as you have to watch for pedestrians, but during green ball phase you have no vehicles to watch out for.

In those situations, the vast majority will be turns with green ball (or perhaps FYA to highlight yielding to peds).  Very few of this situation would involve a red arrow, protected only turn (such as very high pedestrian volume).

No, it's good. You make a legitimate point. I'm sure they're far more common than regular dual-permissive left turns. I don't personally know of any that work this way in WA (all my local examples are from British Columbia), which is why I was initially fine with their inclusion. But all things considered, traffic control-wise, it's certainly not as interesting as a dual permissive left across traffic.

Nevertheless, if someone wanted to share a location where a traffic light works in this fashion, I'm not sure where else they'd post about it. Another reason I was fine with it. If I ran into one in Washington, I might have considered posting it here with the caveat that it's not a true "double permissive left turn" in the sense that there is no "oncoming" vehicular traffic.

Bit late to reply on this, but given a strict reading of the thread's title, a left turn against a crosswalk displaying the walk signal would count. While I agree that it is quite a different in operation due to not needing to yield to opposing traffic, in Traffic Engineering terms this is still considered a permitted/permissive left turn. In fact, the "normal" right turn you mention is also considered a permitted right. (A protected right with a green arrow requires both crosswalks to be Don't Walk and is usually shown with the opposing protected left.)

Agreed


iPhone

[jakeroot]

While this is your thread Jake, I would prefer that examples like this not be included.  There are probably many intersections out there with some form of double left that doesn't need to yield to vehicular traffic, but yields to pedestrians.  Basically, T-intersections or one-way streets.  But these are really different from situations where you would yield to vehicles in the way that you approach them. 

If there is no opposing traffic, in what sense are you making a permissive turn?  The turn is functionally equivalent to a right turn, as you have to watch for pedestrians, but during green ball phase you have no vehicles to watch out for.

In those situations, the vast majority will be turns with green ball (or perhaps FYA to highlight yielding to peds).  Very few of this situation would involve a red arrow, protected only turn (such as very high pedestrian volume).

No, it's good. You make a legitimate point. I'm sure they're far more common than regular dual-permissive left turns. I don't personally know of any that work this way in WA (all my local examples are from British Columbia), which is why I was initially fine with their inclusion. But all things considered, traffic control-wise, it's certainly not as interesting as a dual permissive left across traffic.

Nevertheless, if someone wanted to share a location where a traffic light works in this fashion, I'm not sure where else they'd post about it. Another reason I was fine with it. If I ran into one in Washington, I might have considered posting it here with the caveat that it's not a true "double permissive left turn" in the sense that there is no "oncoming" vehicular traffic.

Bit late to reply on this, but given a strict reading of the thread's title, a left turn against a crosswalk displaying the walk signal would count. While I agree that it is quite a different in operation due to not needing to yield to opposing traffic, in Traffic Engineering terms this is still considered a permitted/permissive left turn. In fact, the "normal" right turn you mention is also considered a permitted right. (A protected right with a green arrow requires both crosswalks to be Don't Walk and is usually shown with the opposing protected left.)

Here I am being late myself.

My original idea with creating this thread was to discuss this style of phasing, not exactly to list each example. But that's what ended up coming from that, and that's totally cool because there really should be a database of these for future study.

At any rate, I think what makes oncoming vehicles more interesting is that they are approaching at various speeds, with varying gaps, and require drivers to give a bit more thought than yielding to pedestrians (who, walking, all travel around the same speed and are certainly less dangerous to cars than the other way around). There is still something very interesting about double left turns yielding to pedestrians, as they are decidedly quite rare, but they are a bit more mundane compared to left turns where yielding to pedestrians and vehicles is required.

Now, in light of there not being a thread for listing those situations, I am fine with them being posted here. It's just that they weren't in the original spirit of the thread (which I had in my head as being "against traffic" but didn't necessarily specify, beyond the listed examples thus far all being against traffic).

[mrsman]

While this is your thread Jake, I would prefer that examples like this not be included.  There are probably many intersections out there with some form of double left that doesn't need to yield to vehicular traffic, but yields to pedestrians.  Basically, T-intersections or one-way streets.  But these are really different from situations where you would yield to vehicles in the way that you approach them. 

If there is no opposing traffic, in what sense are you making a permissive turn?  The turn is functionally equivalent to a right turn, as you have to watch for pedestrians, but during green ball phase you have no vehicles to watch out for.

In those situations, the vast majority will be turns with green ball (or perhaps FYA to highlight yielding to peds).  Very few of this situation would involve a red arrow, protected only turn (such as very high pedestrian volume).

No, it's good. You make a legitimate point. I'm sure they're far more common than regular dual-permissive left turns. I don't personally know of any that work this way in WA (all my local examples are from British Columbia), which is why I was initially fine with their inclusion. But all things considered, traffic control-wise, it's certainly not as interesting as a dual permissive left across traffic.

Nevertheless, if someone wanted to share a location where a traffic light works in this fashion, I'm not sure where else they'd post about it. Another reason I was fine with it. If I ran into one in Washington, I might have considered posting it here with the caveat that it's not a true "double permissive left turn" in the sense that there is no "oncoming" vehicular traffic.

Bit late to reply on this, but given a strict reading of the thread's title, a left turn against a crosswalk displaying the walk signal would count. While I agree that it is quite a different in operation due to not needing to yield to opposing traffic, in Traffic Engineering terms this is still considered a permitted/permissive left turn. In fact, the "normal" right turn you mention is also considered a permitted right. (A protected right with a green arrow requires both crosswalks to be Don't Walk and is usually shown with the opposing protected left.)

Here I am being late myself.

My original idea with creating this thread was to discuss this style of phasing, not exactly to list each example. But that's what ended up coming from that, and that's totally cool because there really should be a database of these for future study.

At any rate, I think what makes oncoming vehicles more interesting is that they are approaching at various speeds, with varying gaps, and require drivers to give a bit more thought than yielding to pedestrians (who, walking, all travel around the same speed and are certainly less dangerous to cars than the other way around). There is still something very interesting about double left turns yielding to pedestrians, as they are decidedly quite rare, but they are a bit more mundane compared to left turns where yielding to pedestrians and vehicles is required.

Now, in light of there not being a thread for listing those situations, I am fine with them being posted here. It's just that they weren't in the original spirit of the thread (which I had in my head as being "against traffic" but didn't necessarily specify, beyond the listed examples thus far all being against traffic).

What makes specific examples interesting is the extent that they are exceptions to a rule.  And to the exent that they are exceptions, we try to discuss why they are present and what circumstances would lead to their being exceptions to the rule.

In most cases when you have a two-way street with a double left turn lane, the vast majority of cases will have a protected only left turn set up.  Left turn permitted only with a protected left turn arrow, and left turns not permitted when opposing traffic has green.  Exceptions to that occur in certain more liberal jurisdictions (like Tucson), or in situations where there are unusually good sight lines, especially if opposing lefts are also prohibited.  These generally provide for a protected left, but also allow for left turns to be made during the phase of opposing traffic as well.  These are interesting as they vary from the expectation.  These are the main subject of this thread.

A special subset of the above can also occur without provision of any left turn protection at all and sometimes even without signals at all. You still have two left turn lanes that can turn left at times other than the protected phase.  Also very unique.

With a dual left turn, where one is an option straight/left lane, the expectation is also generally a protected only turn, but for the most part, these present as split-phased signals (to avoid blocking straight traffic on green ball lights).  Split-phase is a special example of protected left turn.  To the extent that any of these signals are designed to allow a permitted turn while opposing traffic has right of way is also a special exception worthy of discussion (like 1st/Main in L.A. in the 1980's as Jake posted recently).

A dual left turn from a one way street to a one way street does not face opposing traffic other than pedestrians.  Yes, you have to yield to pedestrians so in a technical sense it is a permitted turn.  But the vast majority of these intersections permit the turn at all times.  Occasionally, there may be signage (or state law) prohibiting turn on red [or prohibiting turn on red from the rightmost left turn lane].   But it is extremely rare to find a left from one way to one way that doesn't allow the turn during green ball phase.  In fact, most of these do not even provide any protected left turn at all.  A left turn on arrow only setup is rare and generally only present in very heavy pedestrian crossings or in the presence of protected bike lanes.

Here is an example of a left turn lane and left turn option lane from one way to one way controlled only by regular signal in Downtown Sacramento.  Left turns are even permitted from both lanes on red signal.  Signage reminds drivers that are turning to yield to pedestrians.  Even in a downtown with a significant (but not extreme) level of pedestrian activity, no protected left is provided.  Examples like this abound in Sacramento and many other cities.  A protected left turn in this situation is quite rare.  Those are more noteworthy than the protected/permitted left in such a case.

https://www.google.com/maps/@38.5822031,-121.5004067,3a,75y,100.9h,79.31t/data=!3m6!1e1!3m4!1sOeDqLTJ1MZbCgX-xsfn4Yg!2e0!7i13312!8i6656

Here's a similar example in Baltimore.  No turn on red, and perhaps a leading pedestrain interval, but left turns are permitted without a protected left:

https://www.google.com/maps/@39.2874062,-76.6232488,3a,75y,254.33h,80.99t/data=!3m6!1e1!3m4!1sYB0-4vXZRCqp9CADR9Lozg!2e0!7i13312!8i6656


Similarly with T-interesections.  If one street ends at another at a T-intersection where the terminating street has two left turn lanes, we expect the left turn to be permitted at all times that the signal is green, even if there is a pedestrian crossing.  A left turn on arrow only situation is more rare, usually only used with heavy pedestrian crossings or a bike lane setup or some other unusual hazard.

Here's an example in Los Angeles, Century Park W at Olympic:

https://www.google.com/maps/@34.0532311,-118.4163626,3a,75y,114.07h,76.99t/data=!3m7!1e1!3m5!1segXAI0GciMXMGOBcJb9X7g!2e0!6s%2F%2Fgeo2.ggpht.com%2Fcbk%3Fpanoid%3DegXAI0GciMXMGOBcJb9X7g%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D305.7235%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192

Again, I don't find any of these above examples noteworthy since they don't defy the expectation.  The expectation is that in situations with dual left turn lanes that only need to yield to a pedestrian crossing (and not uncoming vehicles), left turns are allowed during the permitted phase and protected lefts aren't generally even provided.

[jakeroot]

Found another in Chicago: https://goo.gl/maps/Zn42Wji2djFMVPdd9

This brings the Chicago area to three four known installations:

N Sheridan Road @ W Bryn Mawr Ave (option lane)
N Columbus Drive (NB) @ E Grand Ave (former option lane, now two dedicated turns) (NEW)
N Columbus Drive (SB) @ E Illinois Street (former option lane, now two dedicated turns) (NEW)
Thorndale Ave @ Park Blvd, Itasca (true double left) (removed, now an off-ramp from the 390 Toll Road)

[deathtopumpkins]

If you turn around in that new one you'll find another: Columbus SB @ Illinois St

There MAY also be another in Chicago on Sheridan at Devon: https://goo.gl/maps/zTfUKoWth4HEGsUW7

I can't recall the phasing off the top of my head, and Streetview is inconclusive, but I suspect it may just be split phased.

[jakeroot]

If you turn around in that new one you'll find another: Columbus SB @ Illinois St

There MAY also be another in Chicago on Sheridan at Devon: https://goo.gl/maps/zTfUKoWth4HEGsUW7

I can't recall the phasing off the top of my head, and Streetview is inconclusive, but I suspect it may just be split phased.

Guess I need to look around a bit more! Thanks for that fourth one.

The one at Devon looks to be split-phased. Old imagery shows both directions with 4-section signals, which (from what I can tell) are only used in Illinois at split-phased intersections or one-way streets.

[Amtrakprod]

These setups are ALL OVER in TX along I35.
https://www.google.com/maps/@29.4388701,-98.4505458,3a,75y,194.04h,84.4t/data=!3m6!1e1!3m4!1sNj5vp60yDorsCzV_1agVpw!2e0!7i16384!8i8192
https://www.google.com/maps/@29.5102392,-98.3973887,3a,75y,78.86h,90.08t/data=!3m6!1e1!3m4!1sUplL-Jex1X2S_FepM8GBJA!2e0!7i16384!8i8192
https://www.google.com/maps/@29.5400891,-98.3792572,3a,66.8y,11.44h,85.27t/data=!3m6!1e1!3m4!1sJ-qXMICqvlIdN_BAbKOQgw!2e0!7i16384!8i8192
https://www.google.com/maps/@29.552288,-98.3554288,3a,33.9y,340.29h,91.59t/data=!3m6!1e1!3m4!1s0oTChvoS5crsnfABISmdSA!2e0!7i16384!8i8192
https://www.google.com/maps/@29.6002848,-98.2770688,3a,39.6y,321.97h,91.74t/data=!3m6!1e1!3m4!1sQw_svlCdMGP4rMIFgyW2WQ!2e0!7i16384!8i8192
And this!!!!
https://www.google.com/maps/@29.4387288,-98.4609631,3a,31.7y,3.23h,91.26t/data=!3m6!1e1!3m4!1sEnNKghe8vkX2j_TSRMDKgw!2e0!7i16384!8i8192
Flashing yellow arrow and doghouse combo! Shared permissive left turn lanes are strange but common out here!

[jakeroot]

In terms of states with the most number of these, Texas and Colorado might be the leaders. Both are the only states that I've seen that seem to not only permit it, but actively encourage it.

The reason that neither state is mentioned in this list is simply because there are too many to list. Colorado was the first place I saw the setup, and I saw many in Texas when I was there in 2013.

As an example from Colorado, one needs only to take a glance around Castle Rock. At least 90% of their double left turns use permissive phasing (and there are a lot of them). And it's not like they're relics of the past; basically all of them are FYA installations that mostly date from the last 10 years (many which replaced double-doghouse setups).

[Revive 755]

The one at Devon looks to be split-phased. Old imagery shows both directions with 4-section signals, which (from what I can tell) are only used in Illinois at split-phased intersections or one-way streets.

Rockford has plenty of four sections with bimodal arrows for left turns.  The Chicagoland IDOT District doesn't allow them, but since Chicago doesn't follow a lot of IDOT's policies (or the national MUTCD either) anyway . . .

Found another in Chicago: https://goo.gl/maps/Zn42Wji2djFMVPdd9

This brings the Chicago area to three four known installations:

N Sheridan Road @ W Bryn Mawr Ave (option lane)
N Columbus Drive (NB) @ E Grand Ave (former option lane, now two dedicated turns) (NEW)
N Columbus Drive (SB) @ E Illinois Street (former option lane, now two dedicated turns) (NEW)
Thorndale Ave @ Park Blvd, Itasca (true double left) (removed, now an off-ramp from the 390 Toll Road)

NB Sunset Ridge Road at Skokie Boulevard in Northbrook, IL used to have one (left + left-thru-right)
Did Joliet Street at Cass Street in downtown Joliet get removed? (left + left-thru)

[jakeroot]

The one at Devon looks to be split-phased. Old imagery shows both directions with 4-section signals, which (from what I can tell) are only used in Illinois at split-phased intersections or one-way streets.

Rockford has plenty of four sections with bimodal arrows for left turns.  The Chicagoland IDOT District doesn't allow them, but since Chicago doesn't follow a lot of IDOT's policies (or the national MUTCD either) anyway . . .

Good to know. Did not realize that bimodal signals were used in Illinois in any capacity.

Found another in Chicago: https://goo.gl/maps/Zn42Wji2djFMVPdd9

This brings the Chicago area to three four known installations:

N Sheridan Road @ W Bryn Mawr Ave (option lane)
N Columbus Drive (NB) @ E Grand Ave (former option lane, now two dedicated turns) (NEW)
N Columbus Drive (SB) @ E Illinois Street (former option lane, now two dedicated turns) (NEW)
Thorndale Ave @ Park Blvd, Itasca (true double left) (removed, now an off-ramp from the 390 Toll Road)

NB Sunset Ridge Road at Skokie Boulevard in Northbrook, IL used to have one (left + left-thru-right)
Did Joliet Street at Cass Street in downtown Joliet get removed? (left + left-thru)

Another two, that's great! I remember Brandon mentioning the one in Joliet way back when, but there was a bunch of confusion over whether it was split-phased or permissive, with the consensus being that it was permissive. If that street view image is to be believed, there's no question (and I'm sure, with you being familiar with the area, are already well aware of that). Since the image was from September of last year, I highly doubt it has been removed. I had simply forgotten about it (both it, and that Joliet was so close to Chicago).

[deathtopumpkins]

That one from Northbrook, IL reminded me of one I had forgotten about in Cambridge, MA, that I don't think has been mentioned:
https://goo.gl/maps/6nZKYFeKn2PTUmtm9

If it's not clear from the streetview imagery, the dual left from Cambridgeside Pl onto Land Blvd runs concurrently with the signal for the hotel driveway across Land Blvd.

Is this the first "pure" example (i.e. not LTOR) from Mass?

[jakeroot]

That one from Northbrook, IL reminded me of one I had forgotten about in Cambridge, MA, that I don't think has been mentioned:
https://goo.gl/maps/6nZKYFeKn2PTUmtm9

If it's not clear from the streetview imagery, the dual left from Cambridgeside Pl onto Land Blvd runs concurrently with the signal for the hotel driveway across Land Blvd.

Is this the first "pure" example (i.e. not LTOR) from Mass?

Nice find. Judging by that imagery, not everyone is yielding properly!

I think it was mentioned that there was a temporary variation in either Springfield or Worcester (or somewhere else), but that it was removed. That would make this the only permanent one that I know of.

[deathtopumpkins]

And I realized yesterday that there's an almost identical setup downtown that hadn't occured to me either! So I guess it's not the only one.

https://goo.gl/maps/gxEd538jb4eEPbhF9

The dual left from North St to Congress St runs concurrently with the City Hall garage exit across the street.

[jakeroot]

And I realized yesterday that there's an almost identical setup downtown that hadn't occured to me either! So I guess it's not the only one.

https://goo.gl/maps/gxEd538jb4eEPbhF9

The dual left from North St to Congress St runs concurrently with the City Hall garage exit across the street.

Bit awkward with the RHD setup leaving City Hall. Still would count, since left turns yield to everything else, no matter how awkward.

[Revive 755]

Another one that may not have been previously mentioned for Chicagoland:  SB IL 31 at Chicago Street near Downtown Elgin (left plus left-thru).

[jakeroot]

Another one that may not have been previously mentioned for Chicagoland:  SB IL 31 at Chicago Street near Downtown Elgin (left plus left-thru).

That one even has a double 5-section tower, unlike the others from Chicago. Extra cool.

It would seem that Chicago is actually full of these things.

[mrsman]

DC is going through a process of adjusting the signals on all double turns to avoid conflict with pedestrians.  I don't believe there were any double lefts permissive against opposing traffic [which is the main emphasis of this thread], but there were double lefts and double rights against pedestrians that are now going to become protected only turns to separate turning traffic from pedestrians.

In the name of Vision Zero.

https://ddot.dc.gov/page/intersections-dual-turn-lanes