Double left turns with permissive phasing

[jakeroot]

I'm in Indiana for a couple days, and spotted an intersection with two.

East 116th St @ IKEA Way

The eastbound double left turn is now an FYA, but remains permissive.

When I went through it earlier today, at about 1300, the flashing yellow arrows were active. No idea if they were switched so they could be operated based on the time of day.

[stevashe]

Atlanta, GA at Cascade Road on the onramp to I-285 N. Double doghouse configuration, middle lane is a left/thru lane. Not sure how many more double permissive lefts are there in the Atlanta metro area...

If FYA's were to be used at that intersection with the current lane configuration and phasing, would the leftmost signal be an FYA, middle doghouse, and right 3-section signal consisting of all balls?

Looks like it might have been removed: the green arrow is no longer activating for the right-most doghouse, and the option lane arrow has disappeared from the pavement. But the option lane sign is still overhead (see all three in this link). Honestly, this is how all option lane double left turns onto on-ramps should operate. I've seen some that are split phased. To force through traffic to stop just because you have an option lane seems idiotic, especially with the excellent visibility that left turning traffic would typically have (although the shrubs in this median do hamper visibility a bit).

Typically, with option lanes, I think you'd see it where the left-most signal was an FYA, and middle signal was a doghouse with an FYA instead of regular arrows, and a regular 3-section signal on the right. This is how it's done at this intersection in MN.

It also is totally off here: https://www.google.com/maps/@33.7230047,-84.5022569,3a,75y,117.78h,77.02t/data=!3m6!1e1!3m4!1siQe-f0CXUSJHZZ-DNofe2w!2e0!7i16384!8i8192

The new most recent streetview from March 2020 shows the arrow is back on! https://goo.gl/maps/FX9n1X2jMCCkDn6G8 I assume this wasn't available at the time those messages were posted. Since it's back, I'm thinking the light may have just been burnt out. It also suggests that the lane is indeed still an option lane since the sign was also left up, they must have just opted not to reinstall the arrows after repaving for whatever reason.

Another one in Garden City, same county(Nassau). A lagging double permissive turn, rare for turns onto a 2 way street.

https://maps.app.goo.gl/aW6ujm7BVdTXSD9y5

Another cool find. Although moderately less interesting, given the lack of an opposing left turn. Still, yet another good find in New York.

What I find interesting about this intersection is the double left from Oak St has only 1 receiving lane on Commercial Ave!  Seems like an accident waiting to happen for anyone that doesn't know they have to merge within the intersection. Did anyone else notice that?

[kphoger]

What I find interesting about this intersection is the double left from Oak St has only 1 receiving lane on Commercial Ave!  Seems like an accident waiting to happen for anyone that doesn't know they have to merge within the intersection. Did anyone else notice that?

Tell you what, I wouldn't to be parallel-parked where those pickups are!

[fwydriver405]

Thought I'd NEVER see a double permissive left in New England in person ever. This is in Providence RI at the Empire and Fountain St intersection. Left + left-thru configuration with a 4-section Bimodal PPLT (This signal seems to be very common in RI as much as it is in NH)

[Ned Weasel]

Another one in Garden City, same county(Nassau). A lagging double permissive turn, rare for turns onto a 2 way street.

https://maps.app.goo.gl/aW6ujm7BVdTXSD9y5

Another cool find. Although moderately less interesting, given the lack of an opposing left turn. Still, yet another good find in New York.

What I find interesting about this intersection is the double left from Oak St has only 1 receiving lane on Commercial Ave!  Seems like an accident waiting to happen for anyone that doesn't know they have to merge within the intersection. Did anyone else notice that?

What the hell!?  What traffic engineer allowed that!?  If the receiving area was wider, one could argue that it's two unstriped lanes merging down to one after the intersection (which is actually a thing: https://goo.gl/maps/UkpHrMMGTGRrxzCi7), but from what I can measure on Google Maps, there's only 17 feet between those lane stripes.

[jakeroot]

Thought I'd NEVER see a double permissive left in New England in person ever. This is in Providence RI at the Empire and Fountain St intersection. Left + left-thru configuration with a 4-section Bimodal PPLT (This signal seems to be very common in RI as much as it is in NH)

Intriguing, especially given how new it is! Must be a lagging green arrow? Typically, with turns onto one-way streets in downtown areas in similar situations, the green arrow comes on at the end. Could still be a bimodal signal, that displays simultaneous yellow orb and arrow at the very end of the cycle.

Is New York not usually part of New England? Because NYS seems to have quite a few (note post above mine). There's also been at least one in Mass at one point, as well as that "unsignalized" example in Brunswick, ME you posted about on page 14.

Still, probably the part of the country with the least. Several examples have now been located in California, which is the other area of the country I would have grouped in with New England. Other than that, I'm not aware of any in Utah, Montana, or Wyoming, and I don't believe Florida has any examples anymore. I'm 98% sure every other state has at least one example somewhere. MN is a weird example, with tons of double-left FYA signals, but I don't know if they actually use the flashing phase.

[kphoger]

Is New York not usually part of New England?

[jakeroot]

Another one in Garden City, same county(Nassau). A lagging double permissive turn, rare for turns onto a 2 way street.

https://maps.app.goo.gl/aW6ujm7BVdTXSD9y5

Another cool find. Although moderately less interesting, given the lack of an opposing left turn. Still, yet another good find in New York.

What I find interesting about this intersection is the double left from Oak St has only 1 receiving lane on Commercial Ave!  Seems like an accident waiting to happen for anyone that doesn't know they have to merge within the intersection. Did anyone else notice that?

What the hell!?  What traffic engineer allowed that!?  If the receiving area was wider, one could argue that it's two unstriped lanes merging down to one after the intersection (which is actually a thing: https://goo.gl/maps/UkpHrMMGTGRrxzCi7), but from what I can measure on Google Maps, there's only 17 feet between those lane stripes.

Check out this example of a double-left followed by a merge (jump to 0:55). Insanely short. But still nothing compared to merging in the turn .

[jakeroot]

Is New York not usually part of New England?

Thanks. It's just funny to me think of NYS as being so culturally disassociated from "New England" that fwydriver405 would be so stunned to find an example of a double permissive left, when there are countless examples in NYS, many being far less than a day's drive from all but the northern reaches of Maine. For the purposes of this thread, I would have absolutely grouped NYS with other states in that region.

That would be called "the Northeast", I suppose.

[webny99]

Is New York not usually part of New England? Because NYS seems to have quite a few (note post above mine).

Uh, no, definitely not. Either Northeast or Mid-Atlantic, but never New England. That's exclusive to the six small states east of us.

Also, what post? I'm not seeing any NY examples posted... "post above [yours]" turned out to be pretty vague. 

[jakeroot]

Is New York not usually part of New England? Because NYS seems to have quite a few (note post above mine).

Uh, no, definitely not. Either Northeast or Mid-Atlantic, but never New England. That's exclusive to the six small states east of us.

Also, what post? I'm not seeing any NY examples posted... "post above [yours]" turned out to be pretty vague. 

Yes, I got it. New England is also in the Northeast but not all Northeast states are in New England. Or maybe New York is in the Mid-Atlantic region? The fact that you, as a NYS resident, aren't even sure what region it's in with total certainty, shows that it may not be as clear-cut as some make it out to be.

Reply #443; the original quote (by RestrictOnTheHangar) has an example in Nassau County. There are others on Long Island (such as here and here) and other parts of NYC. Flatbush Ave has at least two (@ Tillary & Ave U), and another at Centre & Chambers in Manhattan; I think there's at least one upstate somewhere.

[Amtrakprod]

Is New York not usually part of New England?

Thanks. It's just funny to me think of NYS as being so culturally disassociated from "New England" that fwydriver405 would be so stunned to find an example of a double permissive left, when there are countless examples in NYS, many being far less than a day's drive from all but the northern reaches of Maine. For the purposes of this thread, I would have absolutely grouped NYS with other states in that region.

That would be called "the Northeast", I suppose.

You'll be mocked pretty hard if you come to the real New England and say that NYS is part of it haha. They don't like us and we don't like them, the red sox rivalry didn't help.

[webny99]

Yes, I got it. New England is also in the Northeast but not all Northeast states are in New England. Or maybe New York is in the Mid-Atlantic region? The fact that you, as a NYS resident, aren't even sure what region it's in with total certainty, shows that it may not be as clear-cut as some make it out to be.

I'm 100% sure that New York is in the Northeast. New England and Mid-Atlantic are both subsets of the Northeast. NY fits into the latter if you have to choose, but it's a bit hard to call Buffalo "Mid-Atlantic", so Northeast is really the only safe bet for the state as a whole.

I guess you could also argue that New York is simply its own subset of the Northeast: it's almost as big as New England, after all.

Reply #443; the original quote (by RestrictOnTheHangar) has an example in Nassau County.

Got it, thank you. I had clicked on his link, but overlooked the one in the nested quote.

[NoGoodNamesAvailable]

What the hell!?  What traffic engineer allowed that!?  If the receiving area was wider, one could argue that it's two unstriped lanes merging down to one after the intersection (which is actually a thing: https://goo.gl/maps/UkpHrMMGTGRrxzCi7), but from what I can measure on Google Maps, there's only 17 feet between those lane stripes.

Honestly, par for the course for Nassau county. Plenty of bad engineering to be found.

[jakeroot]

What the hell!?  What traffic engineer allowed that!?  If the receiving area was wider, one could argue that it's two unstriped lanes merging down to one after the intersection (which is actually a thing: https://goo.gl/maps/UkpHrMMGTGRrxzCi7), but from what I can measure on Google Maps, there's only 17 feet between those lane stripes.

Honestly, par for the course for Nassau county. Plenty of bad engineering to be found.

Maybe so, although Nassau County has quite a few examples of what I'm looking for in this thread. So it's not all bad! Although it depends on your perspective, granted.

I guess you could also argue that New York is simply its own subset of the Northeast: it's almost as big as New England, after all.

I vote for this option.

[mrsman]

Is New York not usually part of New England? Because NYS seems to have quite a few (note post above mine).

Uh, no, definitely not. Either Northeast or Mid-Atlantic, but never New England. That's exclusive to the six small states east of us.

Also, what post? I'm not seeing any NY examples posted... "post above [yours]" turned out to be pretty vague. 

Yes, I got it. New England is also in the Northeast but not all Northeast states are in New England. Or maybe New York is in the Mid-Atlantic region? The fact that you, as a NYS resident, aren't even sure what region it's in with total certainty, shows that it may not be as clear-cut as some make it out to be.

Reply #443; the original quote (by RestrictOnTheHangar) has an example in Nassau County. There are others on Long Island (such as here and here) and other parts of NYC. Flatbush Ave has at least two (@ Tillary & Ave U), and another at Centre & Chambers in Manhattan; I think there's at least one upstate somewhere.

This issue is confused as well on this forum given the way that the states are grouped into different regions.  Traditionally, the states were divided as such:

New England: CT, RI, MA, VT, NH, ME
Mid-Atlantic: NY, NJ, PA
Southeast: DE*, MD, VA, WV, plus other southeastern states.

* DE is sometimes grouped with Mid-Atlantic.

The reason why MD, VA, WV were grouped in the southeast was because they are states that are south of the Mason-Dixon line.  But today, those states have more of a northeastern feel, especially MD.

This forum groups all of the New England and Mid-Atlantic states as Northeastern.  This makes for a huge group with more posts than any other region.  IMO, it would have been better to keep this split as two regions: New England and Mid-Atlantic.  The number of posts in each of these regions would be more manageable.

The forum groups DE, MD, VA, and WV as the Mid-Atlantic group.  These states do belong together as a group as they are distinct from the more southern states and the traditoinal Mid-Atlantic states of NY, NJ, and PA.  The problem is that the name doesn't really fit the group.  A better name would be "near south" or the now popular "Delmarva".

In short, NY, NJ, PA are Mid-Atlantic states even though in this forum MD, VA, and WV are grouped (incorrectly) as Mid-Atlantic states.  Given the new political realities in those three states, they are disctinct from other southern states.

[US 89]

Just remembered a double permissive left I encountered in Parker, Colorado about a month ago. It caught me by surprise, as I don’t routinely drive in areas with them.

https://goo.gl/maps/89js24aYYDRwa3sV8

I am not usually a fan of these, but if we’re going to have them I’d say this type of environment is where they fit best: wide open suburban arterials with good sight lines.

[mrsman]

Just remembered a double permissive left I encountered in Parker, Colorado about a month ago. It caught me by surprise, as I don't routinely drive in areas with them.

https://goo.gl/maps/89js24aYYDRwa3sV8

I am not usually a fan of these, but if we're going to have them I'd say this type of environment is where they fit best: wide open suburban arterials with good sight lines.

While this intersection is signalized with 4 aspect FYA signals, GSV shows a red arrow at the same time as green orb in one of the directions.  To me, it seems like the signal is probably operating with TOD changes.  During part of the day, protected only, and at other parts of the day allowing for the permissive FYA indication.

I feel that this is a reasonable compromise.  In many areas that are uncomfortable with allowing a double permissive turn, they could restrict it based on time of day (or actual traffic levels based on sensor readings).  At busier times, it's a regular double left with protected only operation.  At off times, permissive turns are allowed.

To take it one step further, during off times, the DOT can restrict traffic so that only one of the two left turn lanes is used.  A red X lane (similar to what is used on reversible roads) can restrict traffic from using the rightmost of the two dual left turn lanes during times of permissive signal operation.  I don't know of any place that does that, but the possibility exists.  At any event, this avoids the annoying necessity of waiting forever for a green arrow at 2 a.m.

[fwydriver405]

Intriguing, especially given how new it is! Must be a lagging green arrow? Typically, with turns onto one-way streets in downtown areas in similar situations, the green arrow comes on at the end. Could still be a bimodal signal, that displays simultaneous yellow orb and arrow at the very end of the cycle.

The green arrow is actually leading (bimodal yellow+green arrow) at this intersection - was expecting it to be a lagging green arrow. Could it be because of the short distance between intersections?

Thanks. It's just funny to me think of NYS as being so culturally disassociated from "New England" that fwydriver405 would be so stunned to find an example of a double permissive left, when there are countless examples in NYS, many being far less than a day's drive from all but the northern reaches of Maine. For the purposes of this thread, I would have absolutely grouped NYS with other states in that region.

That would be called "the Northeast", I suppose.

I usually don't get out of Northern New England a lot... I usually don't go farther than Boston or the South Shore in MA (outside of 128), west to Lowell/Nashua, and Portland and Rochester to the north.  But you are correct that NYS from my part of Maine is less that a day's drive - about 5 to 10 hours depending on where you go to in NYS.

At least in my area and in New Hampshire, we don't associate NYS as part of New England but we do consider it part of the Northeast. The regions mrsman mentioned on reply no. 443 is how we view these regions though I'm not sure about DE as I have always put it on the mid-Atlantic segment for some time now. 

You'll be mocked pretty hard if you come to the real New England and say that NYS is part of it haha. They don't like us and we don't like them, the red sox rivalry didn't help.

You're sure right on that part!  Even some of the locals in my city think NYS is a part of New England... 

[RestrictOnTheHanger]

Just remembered a double permissive left I encountered in Parker, Colorado about a month ago. It caught me by surprise, as I don't routinely drive in areas with them.

https://goo.gl/maps/89js24aYYDRwa3sV8

I am not usually a fan of these, but if we're going to have them I'd say this type of environment is where they fit best: wide open suburban arterials with good sight lines.

I second the time of day variable phasing comment above. Navigating around shows that the older setup had doghouses over the left turn lanes, but with red arrows instead of red ball on top (for all directions). The FYAs were probably put in to comply with the MUTCD.

[mrsman]

Just remembered a double permissive left I encountered in Parker, Colorado about a month ago. It caught me by surprise, as I don't routinely drive in areas with them.

https://goo.gl/maps/89js24aYYDRwa3sV8

I am not usually a fan of these, but if we're going to have them I'd say this type of environment is where they fit best: wide open suburban arterials with good sight lines.

I second the time of day variable phasing comment above. Navigating around shows that the older setup had doghouses over the left turn lanes, but with red arrows instead of red ball on top (for all directions). The FYAs were probably put in to comply with the MUTCD.

That's quite interesting.  Do you know what the other indications of the doghouses were?  I don't think I've ever seen a 5 aspect signal with a red arrow.  What would each aspect be?

If I could surmise a guess, RA, YA, GA, YA , FYA.  Two YA indications, one to terminate green arrow and one to terminate FYA.  But I'm glad they changed to the more common 4 aspect FYA signals.

[US 89]

Just remembered a double permissive left I encountered in Parker, Colorado about a month ago. It caught me by surprise, as I don’t routinely drive in areas with them.

https://goo.gl/maps/89js24aYYDRwa3sV8

I am not usually a fan of these, but if we’re going to have them I’d say this type of environment is where they fit best: wide open suburban arterials with good sight lines.

I second the time of day variable phasing comment above. Navigating around shows that the older setup had doghouses over the left turn lanes, but with red arrows instead of red ball on top (for all directions). The FYAs were probably put in to comply with the MUTCD.

That's quite interesting.  Do you know what the other indications of the doghouses were?  I don't think I've ever seen a 5 aspect signal with a red arrow.  What would each aspect be?

If I could surmise a guess, RA, YA, GA, YA , FYA.  Two YA indications, one to terminate green arrow and one to terminate FYA.  But I'm glad they changed to the more common 4 aspect FYA signals.

Looks like they were just regular doghouses, but with an arrow in the top instead of a light. Here's a GSV from 2018, before the FYAs went in.

[jakeroot]

For the record, and I don't mean to sound arrogant: there is no need to point out any in Colorado.

Amongst all 50 states, Colorado seems to be the only one that not only allows double permissive left turns, but seems to encourage them. I have yet to find a major city in Colorado that didn't have at least one example, with many (such as Castle Rock, Arvada, Boulder, or Denver proper) having dozens (if not tens of dozens) of examples.

From what I've seen, quite a few do utilize TOD phasing. Colorado was a heavy user of the 'red-arrow in a doghouse' signal for decades. Although this is not to say that most operate this way. I would guess maybe 1 in 10 had this style of phasing.

[RestrictOnTheHanger]

I never knew that type of doghouse was used before FYAs for TOD. These posts from different parts of the country are useful. Not everyone has been to/driven in every state nor knows generally what each jurisdiction does/not do.

[mrsman]

I never knew that type of doghouse was used before FYAs for TOD. These posts from different parts of the country are useful. Not everyone has been to/driven in every state nor knows generally what each jurisdiction does/not do.

I guess to a degree its kind of like Dallas phasing*.  You focus on the signal that is in front of you.  If you are in the left turn lane, your signal is the doghouse.  Since the only people looking at the doghouse are turning left, a red arrow makes sense.  But I think for this to work, the red arrow is only on when the adjacent signals have red orbs.  (but not vice versa, you could have green arrow when adjacent signals have red orbs)


* But unlike Dallas phasing it doesn't seem to block the thru signals from view, so these should not be used for lagging lefts because of yellow trap issues.