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"Michigan Left" Comes To.....Louisiana?!?!?

Started by Anthony_JK, June 10, 2011, 11:15:57 AM

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Anthony_JK


Just found this particularly interesting snippet over at the LADOTD website concerning a recent intersection improvement on the newly completed Ambassador Cafferty Parkway southern extension in Lafayette. It seems that LADOTD is adopting the "Michigan Left" concept for themselves.

http://www.dotd.la.gov/administration/public_info/projects/ambassadorcaffrey/

Quote

This project will construct a J-Turn intersection, which have been used across the country to help traffic flow, increase safety, and reduce travel time.

When the J-Turn intersection is complete, traffic approaching Ambassador Caffery on Chemin Metairie Road will no longer have to wait for a signal to change, but will yield to traffic coming from the left before they pull out and turn right. Once they pull out, traffic will cross to the newly-constructed far left lane where they can wait safely until it is clear to conduct a U-turn to turn back on Ambassador Caffery. At this point they will be able to remain on Ambassador Caffery or turn right to continue on Chemin Metairie

The movement of the J-Turns reduces the likelihood of crashes, especially severe crashes such as side-collisions. Also, where the conventional intersection has 32 conflict points, where crashes can occur, a J-Turn intersection has only 14 conflict points.

Also, because this intersection will not require a signal, drivers will see a decrease in travel time because they will not have to wait on the signal when it is clear to proceed.

Of course, not allowing the cross street (Chemin Metarie Road) to have through access across Ambassador Cafferty probably saves the cost of having a signal there..but how will the locals adapt to having to go through essentially a U-turn and weaving through two lanes of traffic just to continue on??

At least, though, they're not plopping roundabouts on Ambassador Cafferty yet...oh, wait.....


Anthony


dfilpus

The original Michigan Lefts did not block the cross traffic. Cross traffic would just flow through.
The cases I've seen for eliminating the cross traffic here in North Carolina have been for roads that do not have a lot of cross traffic flow. For instance, if both legs of the cross road go into shopping or residential areas where they end then most traffic is going to turn one way or another. There are instances of this in the Superstreet in Chapel Hill, on the US 1 Vass Bypass and US 17 in Leland.

NE2

Haven't there been Michigan Lefts in New Orleans for a long time? To continue westbound on US 90 at the south end of US 61, you have to go straight, U-turn, and then turn right.
pre-1945 Florida route log

I accept and respect your identity as long as it's not dumb shit like "identifying as a vaccinated attack helicopter".

brownpelican


NE2

Quote from: brownpelican on June 11, 2011, 11:33:06 AM
New Orleans never had Mich. lefts.
Then how do you turn left at the intersection of Broad and Tulane?
pre-1945 Florida route log

I accept and respect your identity as long as it's not dumb shit like "identifying as a vaccinated attack helicopter".

Alex

Quote from: NE2 on June 11, 2011, 06:34:47 PM
Quote from: brownpelican on June 11, 2011, 11:33:06 AM
New Orleans never had Mich. lefts.
Then how do you turn left at the intersection of Broad and Tulane?

NE2 is correct, there are no left-hand turns permitted at the junction of US 61/Tulane and US 90/Broad. Unless they have changed it since 11/20/08, when we photographed all perspectives of the U.S. 61 southern terminus.

cjk374

^^^It hasn't changed.  I was there this past April, and you still can't make U-turns.
Runnin' roads and polishin' rails.

NE2

Quote from: cjk374 on June 11, 2011, 10:52:23 PM
^^^It hasn't changed.  I was there this past April, and you still can't make U-turns.
U-turns or left turns?
pre-1945 Florida route log

I accept and respect your identity as long as it's not dumb shit like "identifying as a vaccinated attack helicopter".

froggie

J-turns are a Superstreet concept, not a Michigan Left concept.  Also, if left turns from the main road to the side road are still allowed, this makes the intersection what MnDOT calls a "3/4-intersection".

Anthony_JK

@Froggie:  I stand corrected.

The LADOTD page doesn't say if left turns will be permitted from Ambassador Cafferty to Chemin Metarie Rd; I'm guessing that since there is no signal there, this will be more of a RIRO than anything else.


Anthony

UptownRoadGeek

Quote from: brownpelican on June 11, 2011, 11:33:06 AM
New Orleans never had Mich. lefts.

New Orleans have had "Michigan" lefts since... forever. I once read an article that debated who actually used it first, not sure how accurate it is. Regardless, turn right + u-turn and keep straight + u-term + turn right have been the default left turn procedure in New Orleans for decades.

brownpelican

#11
Quote from: UptownRoadGeek on June 12, 2011, 01:56:08 PM
Quote from: brownpelican on June 11, 2011, 11:33:06 AM
New Orleans never had Mich. lefts.

New Orleans have had "Michigan" lefts since... forever. I once read an article that debated who actually used it first, not sure how accurate it is. Regardless, turn right + u-turn and keep straight + u-term + turn right have been the default left turn procedure in New Orleans for decades.

I stand corrected. I'm getting the Michigan left confused with the J-turn, which is this:



I haven't seen the J-turn anywhere in NOLA.

And yes, you still can't make a left turn anywhere at Tulane & Broad. You gotta take the U-turn (not recommended on Tulane because the median is very narrow and you risk being hit from behind).

UptownRoadGeek

Quote from: brownpelican on June 13, 2011, 03:44:30 PM
I haven't seen the J-turn anywhere in NOLA.

They're all over Jefferson Parish.

Grzrd

LaDOTD recently added a "J-Turn Projects" page on its website, with LaDOTD videos explaining J-Turns and a link to a MoDOT video about J-Turns:
http://www.dotd.la.gov/administration/public_info/projects/j-turn/

Brandon

Quote from: froggie on June 12, 2011, 12:05:32 PM
J-turns are a Superstreet concept, not a Michigan Left concept.  Also, if left turns from the main road to the side road are still allowed, this makes the intersection what MnDOT calls a "3/4-intersection".

And yet many Michigan Lefts along Telegraph act as J-Turns.
"If you think this has a happy ending, you haven't been paying attention." - Ramsay Bolton

"Symbolic of his struggle against reality." - Reg

US71

There is at least one in Missouri: near Osceola on MO 13
Like Alice I Try To Believe Three Impossible Things Before Breakfast



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