Longest turns at intersections (excluding SPUIs)

[jakeroot]

I was making a left turn a few days ago from southbound I-5 in Tacoma, to eastbound WA-512, when it occurred to me (after having shifted into 3rd before I was finished turning) just how long of a turn it is. It replaced a congested loop about twenty years, and has three left turn lanes (unusual in WA), so it was important to make the turn fairly long and not tight.

Measured out, from the center of the stop line, to the point where the dashed markings become regular lane lines (usually after a crosswalk), the turn is about 180 feet in length (longer for the outside lane @ 188 feet).

So, can you guys think of any exceptionally long turns in your area?

Only rule (right now) is that it's not a SPUI (since those always have long turns). No rules about number of crossed lanes, etc. I'm just looking at length.



For an idea of how this would be measured, just use the Google Maps measuring tool. If there's two lanes, an average would be nice.

[tradephoric]

Does this count?  It takes drivers about 420 feet to clear the intersection at the University Parkway DDI in Florida.  If you look on street view, traffic is expected to clear the SB I-75 off-ramp intersection if they make it through the light (as there is no far side traffic lights; even though the SB I-75 off-ramp traffic has dedicated signal heads).  How long would the all red time have to be?  This really isn't even a turn, but it's just interesting to me.


https://www.google.com/maps/@27.388669,-82.4511866,3a,60y,68.81h,90t/data=!3m6!1e1!3m4!1seCykPojVVwGal02v15Hj1g!2e0!7i16384!8i8192

[jakeroot]

No, only because it's a straight-through maneuver.

But it is indeed quite interesting! Must be an insane all-red phase, especially as drivers have to clear the crosswalks first.

The off-ramp right turn would count though. And it looks pretty lengthy.

[MNHighwayMan]

Any intersection with an acute intersecting angle is going to have a long clearing distance.

SE 14th St/US-69 and Indianola Ave, Des Moines

[jakeroot]

Any intersection with an acute intersecting angle is going to have a long clearing distance.

Indeed. I'm willing to count those.

[jeffandnicole]

CR 555 onto NJ 42 North is about 335 feet.  https://goo.gl/maps/KsEDa7j7UqM2 (distance doesn't appear to come up in the link)

Big bonus points for this:  It's a double left turn lane WITHOUT guiding dots to keep you in your lane as you turn!

[roadfro]

Las Vegas Blvd (the Strip) & Harmon Ave, Las Vegas, NV

This intersection (previously discussed in a separate thread about the most signal heads at an intersection) is very wide. Harmon Ave also comes in at a somewhat acute angle.

I measured the NB LVB to WB Harmon left turn distance at around 330 feet from the center of the middle of three turn lanes (the satellite image was kinda grainy so I couldn't see lane lines well, and there are no crosswalk lines--so this is very approximate).

[jakeroot]

Both of those look like I could be in 4th by the time I leave the intersection!

I measured the NB LVB to WB Harmon left turn distance at around 330 feet from the center of the middle of three turn lanes (the satellite image was kinda grainy so I couldn't see lane lines well, and there are no crosswalk lines--so this is very approximate).

Looks good to me. I measured the turn myself and got very nearly the same distance.

Big bonus points for this:  It's a double left turn lane WITHOUT guiding dots to keep you in your lane as you turn!

That is a surprisingly common trait in my area. Not wicked common, but probably 1 in 5 double lefts, maybe. Though a turn that long would almost certainly have them!

[index]

Some of the turns here are 300ish feet.


https://www.google.com/maps/@32.9960109,-80.0388114,207m/data=!3m1!1e3

[Michael]

There's quite a few I found in my area, but for some reason, a lot of them are east of Syracuse.  I looked for ones that were at least 150 feet.  Old Wikimapia uses better quality Google imagery and the measure tool is more accurate, so I used that and used my ad blocker to block the watermark on Google's imagery.  To make the links visible, I had to use new Wikimapia with Bing imagery, but it looks like you have to manually switch to satellite view and may have to zoom out.

NY 326 to NY 5/US 20 west in Auburn, 156 feet

Lodi St to I-81 north, 197 feet

North Salina St to Hiawatha Blvd, 155 feet (same intersection as the previous one)

US 11 south onto Lemoyne Ave, 251 feet (if you start measuring at the split instead of from the stop line)

Taft Road eastbound to US 11 north, 154 feet (the opposing left turn is shorter)

Taft Road eastbound to South Bay Road northbound, 168 feet (just east of the previous one, the opposing left turn is slightly shorter at 157 feet)

Bridge Street to Erie Blvd, 158 feet

I-690 east to Bridge Street northbound

NY 5/Erie Blvd eastbound at Kinne Road, 158 feet

NY 5/Erie Blvd eastbound at NY 92, 246 feet from the gore (151 feet from the stop line)

NY 5 east at it's split from NY 92, 210 feet

NY 92 west at NY 5, 207 feet (same intersection as the previous one)

NY 5 east in Chittenango, 171 feet

NY 5 east to NY 365A in Oneida, 192 feet

NY 5 east to Middle Settlement Road in New Hartford, 152 feet (Bing's imagery shows the turn a bit longer than what I measured)

NY 12 north to NY 5 west, 177 feet (the separate left turn lane is to prevent weaving to NY 12B just to the west of this intersection)

NY 5 west to NY 12 south, 152 feet (same intersection as the previous one)

This one may count: NY 46/49/69 east at NY 26 north in Rome, 592 feet (426 feet if you start measuring from where the curve starts)
(Note that Bing's imagery is a bit off compared to the Google imagery I used to measure)

Lastly, if you're willing to count the entire ramp for this turn, NY 365 east/NY 26 north to South James Street is 717 feet!

[tradephoric]

The intersection of Bee Line Hwy and Northlake Blvd in Florida was mentioned in the longest crosswalk in America thread.  It has a continuous crosswalk of roughly 230 feet and a turning distance of roughly 330 feet.  Florida intersections at their finest...


https://www.google.com/maps/@26.8103964,-80.15265,279m/data=!3m1!1e3

[tradephoric]

Lastly, if you're willing to count the entire ramp for this turn, NY 365 east/NY 26 north to South James Street is 717 feet!

I got that beat.  There is a "Michigan Left" in Concord, North Carolina where drivers have to travel 3,200 feet to complete their left turn.  That's over 0.6 miles!  Compare that to the "Michigan Left" along Woodward Avenue outside Detroit where drivers only have to travel 750 feet to complete their left.

[kphoger]

should have been a b4

[tradephoric]

should have been a b4

Here's a Florida jughandle intersection that looks similar to a Parclo B4.  It also includes lengthy direct left turns. 




https://www.google.com/maps?ll=26.23213,-80.18549&z=17&t=h

[kphoger]

should have been a b4

Here's a Florida jughandle intersection that looks similar to a Parclo B4.  It also includes lengthy direct left turns. 

[img

Sorry, I tried subtly indicating snark by using all lowercase and no punctuation.  Should have been more explicit.   

[riiga]

So, can you guys think of any exceptionally long turns in your area?

No, I can't. It seems my area just doesn't have any intersections wide enough.

EDIT: This previously allowed left turn has a replacement turn that is 550 meters long, but I think it hardly counts.

[Revive 755]

A couple of the longer ones for Chicagoland:

* NB Barrington Road to WB IL 72, around 240 feet.

* EB US 14 to EB Euclid Avenue in Arlington Heights, around 250 feet.

[jakeroot]

Obviously indirect lefts don't count, but they're still an interesting case of how adding more mileage to vehicle trips can improve traffic flow (sometimes).

* EB US 14 to EB Euclid Avenue in Arlington Heights, around 250 feet.

This one seems like it would be easy to hit the curb Euclid Ave if you entered the left turn on a green arrow at-speed (rather than with a green orb, AKA more slowly and more straight-on).

Here's a Florida jughandle intersection that looks similar to a Parclo B4.  It also includes lengthy direct left turns. 

https://i.imgur.com/TO3feyo.jpg
https://i.imgur.com/SKcTgMz.jpg

https://www.google.com/maps?ll=26.23213,-80.18549&z=17&t=h

Looks more like an A4 to me.

So, can you guys think of any exceptionally long turns in your area?

No, I can't. It seems my area just doesn't have any intersections wide enough.

No worries, European engineers instead try to be creative with the little space they have, which I appreciate almost as much. And I'm sure they could have found a way to configure a massive intersection to allow simultaneous left turns, unlike a certain Florida intersection directly above^^.

[MCRoads]

Here is one north of Denver:

[tradephoric]

I know the rule was no SPUI's, but this has got to be worth a mention.  Drivers exiting the freeway have to travel roughly 550 feet before clearing the opposing off-ramp intersection.  Now many would argue that would be considered a separate intersection entirely, but if you look on streetview there are no signal heads directing SB Telegraph traffic south of the freeway bridge (so drivers turning left off the freeway are expected to clear the opposing off-ramp intersection).


https://www.google.com/maps/@42.2641346,-83.2706031,3a,60y,190.73h,88.52t/data=!3m6!1e1!3m4!1swdIIQPWgN4HfheIpGztgWA!2e0!7i16384!8i8192

[jakeroot]

Here is one north of Denver:

https://i.imgur.com/BCsf2NG.jpg

Impressive that they designed the left turns to run concurrently, which a lot of these angled intersections seem to lack.

I know the rule was no SPUI's, but this has got to be worth a mention.  Drivers exiting the freeway have to travel roughly 550 feet before clearing the opposing off-ramp intersection.  Now many would argue that would be considered a separate intersection entirely, but if you look on streetview there are no signal heads directing SB Telegraph traffic south of the freeway bridge (so drivers turning left off the freeway are expected to clear the opposing off-ramp intersection).

https://i.imgur.com/zRe0JKL.jpg
https://www.google.com/maps/@42.2641346,-83.2706031,3a,60y,190.73h,88.52t/data=!3m6!1e1!3m4!1swdIIQPWgN4HfheIpGztgWA!2e0!7i16384!8i8192

Fair enough. That must be a crazy-long all-red phase!

This half-SPUI in Langley, BC has a relatively long stretch to clear as well (Google Maps). The signal to the north creates some pretty significant backups, so you get a fair bit of this.

[tradephoric]

This half-SPUI in Langley, BC has a relatively long stretch to clear as well (Google Maps). The signal to the north creates some pretty significant backups, so you get a fair bit of this.

That's a great example Jake!  That streetview link with traffic backing up through the offf-ramp intersection sums up perfectly the concern i have regarding this type of SPUI design.  Also in that streetview i noticed there is a no right on red sign.  It's fine getting a green when traffic along the arterial is backed up through the intersection (and the arterial traffic that cleared the SPUI are given no indication that the off-ramp traffic has a dedicated green arrow) but don't turn right on red!

[jakeroot]

This half-SPUI in Langley, BC has a relatively long stretch to clear as well (Google Maps). The signal to the north creates some pretty significant backups, so you get a fair bit of this.

That's a great example Jake!  That streetview link with traffic backing up through the offf-ramp intersection sums up perfectly the concern i have regarding this type of SPUI design.  Also in that streetview i noticed there is a no right on red sign.  It's fine getting a green when traffic along the arterial is backed up through the intersection (and the arterial traffic that cleared the SPUI are given no indication that the off-ramp traffic has a dedicated green arrow) but don't turn right on red!

Yeah, it would be nice if they converted it to a permitted turn-on-red. I seem to recall a fair number of cars turning on red anyways. Or at the very least, completing their turns after through traffic finally "cleared the intersection", regardless of the state of the light.

In British Columbia, for the most part, double right turns do not permit moving on red. I can't readily think of any that allow it, although I don't know of any stern rule that outlaws it. Many right turns are via slip lanes with yield signs, but the ones that are signalized (not too many, but some) seem to almost always deny turns on red. I don't know why this is.

[TBKS1]

The measurement is not that great on this, but here's one of the furthest I can find here in Little Rock. I tried to maximize the distance by using the rightmost left turn lane, and turning into the lane that's the furthest to the right side of the road. After that, I found the intersection of Wellington Hills Road and Chenal Parkway in West Little Rock to probably be one of the longest turns over here, at a distance of about 216 feet.

[jakeroot]

The measurement is not that great on this, but here's one of the furthest I can find here in Little Rock. I tried to maximize the distance by using the rightmost left turn lane, and turning into the lane that's the furthest to the right side of the road. After that, I found the intersection of Wellington Hills Road and Chenal Parkway in West Little Rock to probably be one of the longest turns over here, at a distance of about 216 feet.

I think it's a bit more ideal to follow the center line of dual or triple left turns, to get an average. Still, these are a couple of good examples!