Displaced Left Turn Crossover Lane

[AZjeff]

We're spending a week in and around Fort Collins Colorado and came across an intersection configuration I've never seen before called a displaced left turn. Hard to explain but I found a diagram of the traffic pattern. A short left turn lane starts back 50 yards or so from the intersection with a stop light or a yield sign. You have to wait until oncoming traffic clears then cross over the opposing lanes into a turning lane between the opposing lanes and the right turn lane from the traffic going from your left to right through the intersection. You can then sit there with traffic going past you on both sides until you get a green arrow to turn left. I completely missed the first time I should have used one and continued straight on. Came to another one and got a chance to study it and figure out what to do. I asked a local about them and was told they're something fairly new and studies show they reduce accidents at intersectons so more will be created around FoCo. We heard the same about traffic circles when they started putting them in at home. They may reduce accidents right up until a visitor finds one and gets it wrong. Gotta stay on your toes.

 

[Nukeman7]

That looks like a limited and modified version of a diverging diamond intersection which is becoming more prevalent in the U.S.

 

[eljefino]

Seems like a good way to attract headlight glare at night, with oncoming traffic to one's right vice left.

 

[PimTac]

I would think this will cause accidents especially at night during low traffic periods.

 

[Aredeeem]

Gee. Sounds like fun. You notice on the video that not one of these DDI’s has been implemented in New Jersey. Traffic would be reduced by 50% in the first week but only because half of us would kill the other half. We’re still figuring out round a bouts here.

 

[PimTac]

For decades and decades we have been driving using the same rules wherever we go. Suddenly in the last several years they are blowing all that up because a computer model says it’s more efficient.

 

[Hermann]

@AZjeff

There is a very similar intersection over I-35 at MO Hiway-152 (Exit 16) I like the layout but I feel claustrophobic because walls are built on each side 2 lanes wide. Under construction on the way to my lady friend's there is a unique intersection being built on a two lane highways with a 60 mph speed limit. Doesn't look like a roundabout, doesn't look like a diverging diamond, I guess I'll know soon as the wrap up date is targeted for Sept 22

Experienced my first DDI in about 2010 at the I-44, MO Hwy 13 in Springfield MO. They are somewhat common in MO.

 

[KGMtech]

This is weird, now I appreciate the New Jersey left turn even more.

 

[swampdodo]

We're spending a week in and around Fort Collins Colorado and came across an intersection configuration I've never seen before called a displaced left turn. Hard to explain but I found a diagram of the traffic pattern. A short left turn lane starts back 50 yards or so from the intersection with a stop light or a yield sign. You have to wait until oncoming traffic clears then cross over the opposing lanes into a turning lane between the opposing lanes and the right turn lane from the traffic going from your left to right through the intersection. You can then sit there with traffic going past you on both sides until you get a green arrow to turn left. I completely missed the first time I should have used one and continued straight on. Came to another one and got a chance to study it and figure out what to do. I asked a local about them and was told they're something fairly new and studies show they reduce accidents at intersectons so more will be created around FoCo. We heard the same about traffic circles when they started putting them in at home. They may reduce accidents right up until a visitor finds one and gets it wrong. Gotta stay on your toes
View attachment 114384

There is something similar in Atlanta...at least one on exit 104 off of I-85

 

[miden851]

Atlanta's area has built multiple of these intersections in past 5-6 years (diverging diamond intersection), yet they are not the same as the one from the very top

 

[AZjeff]

It looks like the displaced left turn only requires new striping and signage and those cricket bat reflector sticks. "Progress" done cheap.

Have to admit the traffic circles do reduce congestion at some of the high volume intersections around our area. Just have to be real aware of other drivers. The last ones put in were a modified design, the road fades left going in then swings around and the exit is straightened out. slows you down but more gradual turns.

 

[PimTac]

I have a intersection not too far away that has three left turn lanes. It’s nerve wracking just going through that. They must have narrowed the lanes to make them fit. If there is a big truck or something then it’s impossible for everyone to go through together.

 

[wwillson]

We have several of the DDIs here and after a couple weeks of people getting used to them they are great. They flow a lot more traffic than the standard freeway interchanges of yesteryear.

 

[Aredeeem]

I’m sure DDI’s are not a bad idea. But in The state of insanity I drive in there would be a long learning curve. Went out to pick up dinner last night and noticed two cars at the extreme far end of the lot with no other vehicles around. Looks like out of state Marine guy parked first to avoid any dings and of course New Jersey Nissan guy had to “cozy” up to break his chops. This is how we behave out here when we’re standing still. A DDI would be like a Roman chariot race.

 

[64bawagon]

Hard to imagine this in a state (Michigan) where many people cant even pull off a 3 or 4 way stop intersection without freezing up

 

[MNgopher]

Have not come across one of those left turn lanes before...

I am a big fan of roundabouts and DDI intersections. Former employer installed roundabouts at multiple intersections that had a thru road and a stopping road. Every couple of years, someone would blow a stop sign, and fatalities ensued. Once the roundabouts went in, we still have accidents at the intersection, but they have changed from fatalities to fender benders...

And the DDI interchanges can flow a significant amount of traffic much more efficiently. We are using them in more places...

 

[MNgopher]

Hard to imagine this in a state (Michigan) where many people cant even pull off a 3 or 4 way stop intersection without freezing up

Old joke here - 4 Minnesotan's all pull up to a stop sign at the same time. They all die of starvation...

 

[tyman]

Old joke here - 4 Minnesotan's all pull up to a stop sign at the same time. They all die of starvation...

ope

 

[Aredeeem]

That is funny. In New Jersey the first two drivers give each other the finger, and proceed aggressively. They’re lives saved only because they’re making opposing turns. Driver #3 proceeds cautiously into the intersection, closes his eyes and darts across. Driver #4, who is 95 years old and got his license when Herbert Hoover was President breaks off the pattern and returns home, hoping that tomorrow he can remember why he went out in the first place. Turn signals?? That’s something you do in your driveway after you get home.

 

[Pew]

Colorado has some rather weird road rules that I have rarely come across in other states. I got rear ended at the "right-turn on red and merge into traffic" and one that I rarely come across in other states except busy national/state parks.

We have several of the DDIs here and after a couple weeks of people getting used to them they are great. They flow a lot more traffic than the standard freeway interchanges of yesteryear.

DDIs helped the rt59/i88 alot and it looks like they're almost done with the Weber/I55 one too. Thank god because those intersections are getting a nasty amount of traffic.

ope

'scuse me, I'm just gonna sneak on by you.