AARoads Forum

Left turns are the bane of traffic engineers, ruining the otherwise perfect signal precession that could guarantee drivers green lights.

But in the 60s, Michigan solved that problem by incorporating u turns into the medians of divided highways to allow for left turn movements while prohibiting them from the main intersection
(https://i.imgur.com/FprxMK0.png)

Studies have shown they result in enormous improvements in safety and traffic flow. Because they also require the use of a wide median, they offer space for landscaping and stormwater drainage.

Imagine if this had become the standard design for new arterial streets all over the country, and perhaps the world. Think of all the time, money, and lives saved.

Why the f*ck aren't these everywhere?

Not that I disagree but it is worth noting that there are other factors in play around Metro Detroit where a good chunk of Michigan Lefts are located.  Some of the traffic flow on arterials into Detroit has been impacted by the largely free flowing limited access capacity around them.  With the decline of the automotive industry there just isn't nearly as much traffic in general flowing into Detroit on arterials or limited access roadways. 

That said, Florida leaps off the page in my mind as a state where Michigan lefts could be a huge benefit given there is a huge reliance on timed signals.  One of the most frustrating things about driving around a surface highway in Florida  is waiting for a long left hand turn light to run its cycle.

How about one of its variants, like the Superstreet/J-turn OH 4B uses?

Not on OH 4B, but here's one of the fancier superstreets (https://www.google.com/maps/@39.8678926,-82.9356867,336m/data=!3m1!1e3) in the state.

Even better, use jughandles like in NJ, where not only can you prohibit left turns, but all turning traffic keeps to the right, and faster traffic can pass on the left without anyone slowing down.

The fact that they require a larger median is a negative, not a positive.

Quote from: kernals12 on July 16, 2021, 12:29:35 PM
Left turns are the bane of traffic engineers, ruining the otherwise perfect signal precession that could guarantee drivers green lights.

But in the 60s, Michigan solved that problem by incorporating u turns into the medians of divided highways to all for left turn movements while prohibiting them from the main intersection
(https://i.imgur.com/FprxMK0.png)

Studies have shown they result in enormous improvements in safety and traffic flow. Because they also require the use of a wide median, they offer space for landscaping and stormwater drainage.

Imagine if this had become the standard design for new arterial streets all over the country, and perhaps the world. Think of all the time, money, and lives saved.

Why the f*ck aren't these everywhere?

Michigan Lefts are a pain ... trust me on this:  You don't want them everywhere.

Quote from: kernals12 on July 16, 2021, 12:29:35 PMenormous improvements in safety and traffic flow

*In studies where flow is measured amongst thru traffic only.  These traffic studies often make the assumption that the majority of traffic at an intersection will proceed straight, rather than turning.  This is NOT a safe assumption to make at an impressive percentage of major intersections.

Another issue- Michigan lefts require a wide enough median to facilitate a left turn.  If trucks are involved, that requires an even wider space.  Even in the illustration above, the median appears to be about 36 feet wide.  That's a wide enough corridor to put in three traffic lanes!  Two 12-foot lanes in each direction, plus 36 feet in the median, and say, 20 feet on either side of the road, amounts to 104 feet of right-of-way.  You need a corridor at least 100 feet wide to make this happen.  Michigan planned their roads to be this way from the get-go; good luck retrofitting this scheme somewhere else.

Quote from: paulthemapguy on July 16, 2021, 02:17:37 PM

Quote from: kernals12 on July 16, 2021, 12:29:35 PMenormous improvements in safety and traffic flow

*In studies where flow is measured amongst thru traffic only.  These traffic studies often make the assumption that the majority of traffic at an intersection will proceed straight, rather than turning.  This is NOT a safe assumption to make at an impressive percentage of major intersections.

Another issue- Michigan lefts require a wide enough median to facilitate a left turn.  If trucks are involved, that requires an even wider space.  Even in the illustration above, the median appears to be about 36 feet wide.  That's a wide enough corridor to put in three traffic lanes!  Two 12-foot lanes in each direction, plus 36 feet in the median, and say, 20 feet on either side of the road, amounts to 104 feet of right-of-way.  You need a corridor at least 100 feet wide to make this happen. Michigan planned their roads to be this way from the get-go; good luck retrofitting this scheme somewhere else.

Notice how the title says new arterials.

But it's still a factor.  It probably is a more difficult sell to plan an arterial road with a huge median versus one that follows a more conventional width.  That wide median means less room for development along the arterial highway.

Quote from: renegade on July 16, 2021, 02:10:41 PM

Quote from: kernals12 on July 16, 2021, 12:29:35 PM
Left turns are the bane of traffic engineers, ruining the otherwise perfect signal precession that could guarantee drivers green lights.

But in the 60s, Michigan solved that problem by incorporating u turns into the medians of divided highways to all for left turn movements while prohibiting them from the main intersection
(https://i.imgur.com/FprxMK0.png)

Studies have shown they result in enormous improvements in safety and traffic flow. Because they also require the use of a wide median, they offer space for landscaping and stormwater drainage.

Imagine if this had become the standard design for new arterial streets all over the country, and perhaps the world. Think of all the time, money, and lives saved.

Why the f*ck aren't these everywhere?

Michigan Lefts are a pain ... trust me on this:  You don't want them everywhere.

Try experiencing life without them.

Quote from: Max Rockatansky on July 16, 2021, 07:52:48 PM
But it's still a factor.  It probably is a more difficult sell to plan an arterial road with a huge median versus one that follows a more conventional width.  That wide median means less room for development along the arterial highway.

I didn't think about that. Who needs enormous improvements in throughput and safety? Won't someone think of the strip malls and car dealerships!

MA 9 through the Golden Triangle (https://www.google.com/maps/@42.298945,-71.3983906,185m/data=!3m1!1e3), a massive retail area, in Natick and Framingham, probably has just enough width to accommodate Michigan Lefts. Not to mention how much nicer it would be if the rusty metal guardrail made way a nicely landscaped median that could also serve to drain the enormous volume of stormwater runoff from the massive parking lots in the area that frequently floods the Speen Street underpass

Quote from: kernals12 on July 16, 2021, 07:56:56 PM

Quote from: Max Rockatansky on July 16, 2021, 07:52:48 PM
But it's still a factor.  It probably is a more difficult sell to plan an arterial road with a huge median versus one that follows a more conventional width.  That wide median means less room for development along the arterial highway.

I didn't think about that. Who needs enormous improvements in throughput and safety? Won't someone think of the strip malls and car dealerships!

I mean, those properties do generate money and tax revenue.  Kind of a difficult sell to propose a road that will be more efficient in flowing traffic but attract less develop along side it. 

Another consideration worth noting is how willing the traveling public will be to accept more difficult access to businesses for the sake of better through traffic flow?  Example; on Grand River Avenue one often couldn't just turn left into a business and had to flip a U-turn at the next Michigan left.  That U-turn process isn't as often seamless as you think it is, especially it involves driving several blocks past where you want to go.  People in Metro Detroit might be used to that, but in places like Florida they would lose their minds about not being able to turn left into a business. 

The Michigan Left's waterloo could be its main draw: throughput. Do new arterials really need the capacity offered by Michigan Lefts? Or is a five lane road with TWLTL sufficient?

On top of that, they can get so aggressively wide and take so much land, they simply aren't practical in some areas. Land is so expensive in the Seattle region that building a Michigan Left corridor is basically out of the question. Too much land. WSDOT has already spent 30 years buying land for a new freeway (WA-167), and you'd need to widen a road dramatically to make it a true Michigan Left corridor.

There's also the simple matter of there not being any new arterial streets. Most development in Seattle is infill. The only new roads are neighborhood streets and some arterial widening as necessary.

They are also miserable experiences for pedestrians. The lack of consistent four-way intersections creates long distances between "given" crossing points (those created by the simple intersection of two streets). Speaking of long distance walks: the crossings are very long too, and you often have to deal with double right turns that frequently have only a yield condition.

The only time I think they could be used is along corridors with either a busway in the centre or maybe a rail line down the median (either raised or at-grade).

Quote from: jakeroot on July 16, 2021, 08:22:38 PM
They are also miserable experiences for pedestrians. The lack of consistent four-way intersections creates long distances between "given" crossing points (those created by the simple intersection of two streets). Speaking of long distance walks: the crossings are very long too, and you often have to deal with double right turns that frequently have only a yield condition.

Just cross one direction at a time when it's clear; it will periodically clear out due to the traffic signals. If you're walking along it, it doesn't have to be at an intersection.

Quote from: 1 on July 16, 2021, 08:35:55 PM

Quote from: jakeroot on July 16, 2021, 08:22:38 PM
They are also miserable experiences for pedestrians. The lack of consistent four-way intersections creates long distances between "given" crossing points (those created by the simple intersection of two streets). Speaking of long distance walks: the crossings are very long too, and you often have to deal with double right turns that frequently have only a yield condition.

Just cross one direction at a time when it's clear; it will periodically clear out due to the traffic signals. If you're walking along it, it doesn't have to be at an intersection.

That's what we used to do on Grand River given we would had to walk several blocks to the next pedestrian signal.  In a place like Seattle that lack of pedestrian friendliness would never fly.

Quote from: Max Rockatansky on July 16, 2021, 08:41:03 PM

Quote from: 1 on July 16, 2021, 08:35:55 PM

Quote from: jakeroot on July 16, 2021, 08:22:38 PM
They are also miserable experiences for pedestrians. The lack of consistent four-way intersections creates long distances between "given" crossing points (those created by the simple intersection of two streets). Speaking of long distance walks: the crossings are very long too, and you often have to deal with double right turns that frequently have only a yield condition.

Just cross one direction at a time when it's clear; it will periodically clear out due to the traffic signals. If you're walking along it, it doesn't have to be at an intersection.

That's what we used to do on Grand River given we would had to walk several blocks to the next pedestrian signal.  In a place like Seattle that lack of pedestrian friendliness would never fly.

Let me just roll off this massive AASHTO-style curb...

(https://media1.tenor.com/images/8e174d24dfe30a021e10682589a9e2dd/tenor.gif?itemid=8902077)

Quote from: jakeroot on July 16, 2021, 08:45:47 PM

Quote from: Max Rockatansky on July 16, 2021, 08:41:03 PM

Quote from: 1 on July 16, 2021, 08:35:55 PM

Quote from: jakeroot on July 16, 2021, 08:22:38 PM
They are also miserable experiences for pedestrians. The lack of consistent four-way intersections creates long distances between "given" crossing points (those created by the simple intersection of two streets). Speaking of long distance walks: the crossings are very long too, and you often have to deal with double right turns that frequently have only a yield condition.

Just cross one direction at a time when it's clear; it will periodically clear out due to the traffic signals. If you're walking along it, it doesn't have to be at an intersection.

That's what we used to do on Grand River given we would had to walk several blocks to the next pedestrian signal.  In a place like Seattle that lack of pedestrian friendliness would never fly.

Let me just roll off this massive AASHTO-style curb...

(https://media1.tenor.com/images/8e174d24dfe30a021e10682589a9e2dd/tenor.gif?itemid=8902077)

Heh, it was amusing to see my elderly Grand Father try to run across Grand River.  He wasn't exactly sure footed but as far as I know he never had a serious close calls with traffic.  My Mom certainly didn't like what he was doing but he insisted on not putting miles on the Chevette (later a Malibu). 

Quote from: kernals12 on July 16, 2021, 07:54:48 PM

Quote from: renegade on July 16, 2021, 02:10:41 PM

Quote from: kernals12 on July 16, 2021, 12:29:35 PM
Left turns are the bane of traffic engineers, ruining the otherwise perfect signal precession that could guarantee drivers green lights.

But in the 60s, Michigan solved that problem by incorporating u turns into the medians of divided highways to all for left turn movements while prohibiting them from the main intersection
(https://i.imgur.com/FprxMK0.png)

Studies have shown they result in enormous improvements in safety and traffic flow. Because they also require the use of a wide median, they offer space for landscaping and stormwater drainage.

Imagine if this had become the standard design for new arterial streets all over the country, and perhaps the world. Think of all the time, money, and lives saved.

Why the f*ck aren't these everywhere?

Michigan Lefts are a pain ... trust me on this:  You don't want them everywhere.

Try experiencing life without them.

They're not exactly life support.  Try driving with them.  They're a pain.  Trust me on that.

Quote from: thspfc on July 16, 2021, 01:48:44 PM
The fact that they require a larger median is a negative, not a positive.

MO 141 in Fenton (https://goo.gl/maps/WK6nabosUMA9d4hh7) doesn't have a wide median for its Michigan left. (https://goo.gl/maps/CiQNe58BKJUNRLDH7)

Nor do the medians appear wide (https://goo.gl/maps/GSLzAnPLkwJgRJ3t8) for the one in Fishers, IN (https://goo.gl/maps/31EHAmeLx1e4Pw278)

The disadvantages are they are usually about a quarter of a mile down the street so you have to go about a half mile out of your way in order to make a left turn and you have to stop up to three times to make one left turn.

Quote from: Revive 755 on July 16, 2021, 10:17:06 PM

Quote from: thspfc on July 16, 2021, 01:48:44 PM
The fact that they require a larger median is a negative, not a positive.

MO 141 in Fenton (https://goo.gl/maps/WK6nabosUMA9d4hh7) doesn't have a wide median for its Michigan left. (https://goo.gl/maps/CiQNe58BKJUNRLDH7)

Nor do the medians appear wide (https://goo.gl/maps/GSLzAnPLkwJgRJ3t8) for the one in Fishers, IN (https://goo.gl/maps/31EHAmeLx1e4Pw278)

Grant Rd. in Tucson, AZ has Michigan lefts like Fenton, MO.

https://goo.gl/maps/iUPDEEHVWea7kf5z5 (https://goo.gl/maps/iUPDEEHVWea7kf5z5)

Those are kind of similar to Michigan Lefts, but aren't really the same thing (I think they are called J-turns). Michigan Lefts usually allow right-on-red and then left-on-red for the U-turn, and no bulb-out is required to accommodate the U-turns.

Practically, they are very similar and you can achieve a lot of the same goals with them, but they technically operate a bit differently.

Michigan Lefts are a bit easier to modify too, since you can pretty easily add or delete lanes, U-turn points, and other bits as necessary. And the large bulb-out can be kind of ugly, just from a personal point of view.

Quote from: kernals12 on July 16, 2021, 12:29:35 PM
Left turns are the bane of traffic engineers, ruining the otherwise perfect signal precession that could guarantee drivers green lights.

But in the 60s, Michigan solved that problem by incorporating u turns into the medians of divided highways to allow for left turn movements while prohibiting them from the main intersection
(https://i.imgur.com/FprxMK0.png)

Studies have shown they result in enormous improvements in safety and traffic flow. Because they also require the use of a wide median, they offer space for landscaping and stormwater drainage.

Imagine if this had become the standard design for new arterial streets all over the country, and perhaps the world. Think of all the time, money, and lives saved.

Why the f*ck aren't these everywhere?

I agree that the Michigan Left or similar treatments such as the superstreet should be used everywhere it is possible. The superstreet design used in North Carolina, especially when the road is converted before the commercial development occurs, is what I think should happen on most arterials.

Around here, if you put in a screwy design like that people will just ignore it and turn left anyway. It happened for months on Telegraph Road (VA-241) in Alexandria when they built a new ramp on the right to replace an old left turn at a light–people still illegally turned left–and people still make U-turns two lights down the road instead of using the ramp to South Kings Highway in the same area.

I suspect part of it is outdated sat-navs. If the device says to turn left, some people are flat-out determined to turn left, period.

Edited to add one other thing the OP will never accept: A lot of municipalities do not WANT to "guarantee drivers green lights." Plenty of places view that as anathema.

Quote from: kernals12 on July 16, 2021, 07:56:56 PM

Quote from: Max Rockatansky on July 16, 2021, 07:52:48 PM
But it's still a factor.  It probably is a more difficult sell to plan an arterial road with a huge median versus one that follows a more conventional width.  That wide median means less room for development along the arterial highway.

I didn't think about that. Who needs enormous improvements in throughput and safety? Won't someone think of the strip malls and car dealerships!

If the road isn't a freeway to begin with, then I must assume access is actually important.  Access to what?  Homes and businesses.  Take away the space for said homes and businesses, and you're defeating the function the road serves to begin with.

Quote from: kernals12 on July 16, 2021, 07:49:54 PM
Notice how the title says new arterials.

Quote from: jakeroot on July 16, 2021, 08:22:38 PM
On top of that, they can get so aggressively wide and take so much land, they simply aren't practical in some areas. Land is so expensive in the Seattle region that building a Michigan Left corridor is basically out of the question. Too much land

So it costs more to construct, and it reduces the amount of room for revenue-generating businesses to be built.  Golly, why aren't these things everywhere?

Quote from: kernals12 on July 16, 2021, 07:54:48 PM

Quote from: renegade on July 16, 2021, 02:10:41 PM
Michigan Lefts are a pain ... trust me on this:  You don't want them everywhere.

Try experiencing life without them.

wut

I experience life without them every day.

Quote from: jakeroot on July 16, 2021, 08:22:38 PM
Do new arterials really need the capacity offered by Michigan Lefts? Or is a five lane road with TWLTL sufficient?

An underappreciated point.  Michigan lefts add a layer of complexity for meager (or was it "massive"?) improvement to traffic flow.  The list of places where they're actually needed is smaller than "everywhere".

Lets see, they cost more to build, reduce tax-productive land, increase VMT, decrease bike and ped access.....for a few seconds of travel time savings for other drivers?

Seems like a bad deal.

Quote from: jakeroot on July 16, 2021, 08:22:38 PM
Or is a five lane road with TWLTL sufficient?

I'd really rather move away from the undivided five-laner.  I realize Michigan Lefts take up huge amounts of space and make them infeasible in most places, but, as for the rest of the road design, I'd much rather see a raised median and with the only unprotected cross traffic being well spaced left turns from the arterial.  I'd rather see everything else be RIRO except at signalized intersections.

Quote
They are also miserable experiences for pedestrians. The lack of consistent four-way intersections creates long distances between "given" crossing points (those created by the simple intersection of two streets).

Simple intersections of two streets are not good pedestrian crossing points, though, if you're talking about non-signalized intersections involving an arterial road.  Sure, they often have legal crosswalks, usually unmarked, but it's no fun trying to cross 35-to-50-MPH traffic that isn't going to stop any time soon.

I really would like to see more left turn alternatives to allow two-phase traffic signals, as opposed to three or four phases, on expressways that have signalized intersections.  It's very pertinent to ask, what is the best way to handle left turn phases at signalized intersections on expressways and superstreet arterials?  I feel like a lot of departments of transportation don't spend a lot of time asking this question.  The main downfall to Michigan Lefts and jughandles, however, will generally be the amount of land they require.

Michigan lefts aren't that bad. I went through one yesterday at Rochester and Big Beaver in Troy and just had to wait for the light at Rochester as the one to turn right was green and the turn around was green when I got there. I was going for NB I-75 and the exit at Rochester is closed so I had to go up to the Big Beaver exit.

In 1924, the Rapid Transit Commission proposed the Super-Highway Plan for Greater Detroit which featured 204-foot "Super-Highways" which was enough space to fit 8-lanes of vehicular traffic and inter-urban rail running down the medians.  Then in 1967, decades after the first "Super-Highway" was built, the first Michigan left was installed at 8 Mile & Livernois.  But from the start the wide-medians were designed to move rail and not a design feature of the "Michigan Left".

(https://i.imgur.com/AWfnVtW.png)

Jughandles don't have to take up much space. (https://goo.gl/maps/Mznu1pKtLFSC4oib8) (Note that while it's a large intersection for the Northeast, only a small portion of it is a jughangle. You're looking for the "turn right to turn left" portion.)

Quote from: tradephoric on July 23, 2021, 08:31:03 AM
In 1924, the Rapid Transit Commission proposed the Super-Highway Plan for Greater Detroit which featured 204-foot "Super-Highways" which was enough space to fit 8-lanes of vehicular traffic and inter-urban rail running down the medians.  Then in 1967, decades after the first "Super-Highway" was built, the first Michigan left was installed at 8 Mile & Livernois.  But from the start the wide-medians were designed to move rail and not a design feature of the "Michigan Left".

(https://i.imgur.com/AWfnVtW.png)

You have the right intersection for the first one but it was in the early 60's that this one was built.

The wide streets of Detroit extended into the city center too.  It all harkens back to the Governor and Judge's plan for Detroit introduced by Augustus Woodward in 1807 after a fire in 1805 burned the city to the ground.  The N/S streets were designed at a whopping 200 feet wide with the radial avenues at 120 feet wide.  This is the result of the plan:

(https://i.imgur.com/oj08m.jpeg)

(https://big.assets.huffingtonpost.com/Tr9dAyM.jpg)

Quote from: stridentweasel on July 23, 2021, 06:49:46 AM

Quote from: jakeroot on July 16, 2021, 08:22:38 PM
Or is a five lane road with TWLTL sufficient?

I'd really rather move away from the undivided five-laner.  I realize Michigan Lefts take up huge amounts of space and make them infeasible in most places, but, as for the rest of the road design, I'd much rather see a raised median and with the only unprotected cross traffic being well spaced left turns from the arterial.  I'd rather see everything else be RIRO except at signalized intersections.

I'm fine with that design too. My point wasn't to say that five-lane undivided roads were inherently superior to all other designs, just that it works just as well as Michigan Left corridors under most circumstances. They can be a little sketchy sometimes, but overall are not immediately dangerous and are much more compact and thus significantly cheaper.

Corridors with constant medians and occasional left turn pockets are fine, but they introduce additional issues: drivers have to go further to do simple maneuvers; U-turns are now a required feature, so hopefully the road is wide enough to do that without bulb-out points; U-turns at every intersection also eliminate the possibility for right-turn green arrows, which reduces capacity; worst of all, they reduce crossing points for pedestrians down to just major intersections, where they are likely to interact with other vehicular traffic as well (this can be mitigated with mid-block crossings, but these don't seem to be as common as they should be). That also relates to your second point...

Quote from: stridentweasel on July 23, 2021, 06:49:46 AM

Quote from: jakeroot on July 16, 2021, 08:22:38 PM
They are also miserable experiences for pedestrians. The lack of consistent four-way intersections creates long distances between "given" crossing points (those created by the simple intersection of two streets).

Simple intersections of two streets are not good pedestrian crossing points, though, if you're talking about non-signalized intersections involving an arterial road.  Sure, they often have legal crosswalks, usually unmarked, but it's no fun trying to cross 35-to-50-MPH traffic that isn't going to stop any time soon.

Simple intersections are not perfect, but they at least provide a crossing point for regular, if not agile pedestrians. Michigan Left and RCUT/J-Turn corridors basically force everyone down to the just the major intersections, making walk times much, much longer than skipping across the road at this or that intersection. You can run across the median and hop over whatever may be in the way, but that's not exactly a feature. At least busy non-signalized intersections can have part-time signals or crosswalks painted if they become major crossings over time. No such option along median corridors without comparatively expensive construction.

Quote from: stridentweasel on July 23, 2021, 06:49:46 AM
I really would like to see more left turn alternatives to allow two-phase traffic signals, as opposed to three or four phases, on expressways that have signalized intersections.  It's very pertinent to ask, what is the best way to handle left turn phases at signalized intersections on expressways and superstreet arterials?  I feel like a lot of departments of transportation don't spend a lot of time asking this question.  The main downfall to Michigan Lefts and jughandles, however, will generally be the amount of land they require.

I think it's quite likely that "alternative" options do come up, but they are very quickly eliminated for exactly the reasons you mention. Practically speaking, jughandles and Michigan Left corridors require a lot of land. As previously mentioned by myself, they just aren't practical as a feature for an upgraded urban or even suburban roadway unless land is cheap and there is little in the way of existing structures. Otherwise, the best you can do, realistically, is adding left turn capacity.

One option not considered enough is reducing phases without adding something else to replace it. If you need additional left turn capacity for this approach, maybe reduce the capacity for another approach to make up for it. This was done westbound along BC-97 in Kelowna, at the left turn onto Pandosy: the city added advanced lefts to a few intersections, but had to remove the advanced left (https://goo.gl/maps/fDhrvkjBcKpgVcci9) (original design (https://goo.gl/maps/yPAePVi8b2R3tAsW9)) to make up for the additional green time needed elsewhere. Is this ideal compared to total reconstruction of BC-97 to keep that advanced left? I would argue: yes. Total reconstruction is insanely expensive and intrusive. If you really need that much extra capacity, consider a bypass or new corridor instead. In my humble opinion.

Quote from: 1 on July 23, 2021, 08:34:35 AM
Jughandles don't have to take up much space. (https://goo.gl/maps/Mznu1pKtLFSC4oib8) (Note that while it's a large intersection for the Northeast, only a small portion of it is a jughangle. You're looking for the "turn right to turn left" portion.)

That's about on par with the ones in Spain, which is fine if they're only used to make U-turns.  But if you're using them to connect to a cross-street, you probably want them farther from the main intersection.

Quote from: jakeroot on July 23, 2021, 02:13:07 PM
U-turns at every intersection also eliminate the possibility for right-turn green arrows

I beg your pardon!  https://goo.gl/maps/2Rqzts3Mi96kcTiT6 , https://goo.gl/maps/Ae18hxRUwHwYKGvR7 , https://goo.gl/maps/iaXCscQnstRkuaEYA .  Frankly, though, I prefer FYAs for that purpose, as are now used at this intersection (Street View needs to catch up here): https://goo.gl/maps/dP6beDoG9afRZMSr6

Quote from: tradephoric on July 23, 2021, 12:19:43 PM
The wide streets of Detroit extended into the city center too.  It all harkens back to the Governor and Judge's plan for Detroit introduced by Augustus Woodward in 1807 after a fire in 1805 burned the city to the ground.  The N/S streets were designed at a whopping 200 feet wide with the radial avenues at 120 feet wide.  This is the result of the plan:

(https://i.imgur.com/oj08m.jpeg)

(https://big.assets.huffingtonpost.com/Tr9dAyM.jpg)

Detroit is a very old city and up until about 100 or so years ago only extended out to Grand Blvd. and then to 8 Mile in the 1920's. It was modeled after Washington, DC which had just been planned not too long prior. Downtown can be somewhat tricky to navigate if you don't know where you're going due to the street system. And it's been altered in places as well.

Quote from: stridentweasel on July 23, 2021, 09:03:40 PM

Quote from: jakeroot on July 23, 2021, 02:13:07 PM
U-turns at every intersection also eliminate the possibility for right-turn green arrows

I beg your pardon!  https://goo.gl/maps/2Rqzts3Mi96kcTiT6 , https://goo.gl/maps/Ae18hxRUwHwYKGvR7 , https://goo.gl/maps/iaXCscQnstRkuaEYA .  Frankly, though, I prefer FYAs for that purpose, as are now used at this intersection (Street View needs to catch up here): https://goo.gl/maps/dP6beDoG9afRZMSr6

But we both know that such setups are inadvisable along corridors where there is an expectation of frequent U-turns. Tucson got around this for years using a right-facing FYA that was active during the overlapping left turn green arrow, but I don't know if they still install them.

I think Metro Vancouver does it right. Medians are very common here along arterial corridors, but they don't go for hundreds of meters between gaps in the median (King George Blvd in Surrey (https://www.google.com/maps/@49.1834449,-122.8474662,453a,35y,12.14h,61.56t/data=!3m1!1e3) is a decent example). This is perfect: (1) it doesn't intentionally create lots of need for U-turns (which can become problematic at intersections), (2) it maintains a somewhat-regular interval of crossing points for pedestrians, and (3) somewhat eliminates the free-for-all of two-way turn lanes (though waiting in median gaps to merge is pretty common). Additionally, (4) add-lane-style slip lanes are used at busy intersections, allowing right turns and U-turns to occur simultaneously (example (https://goo.gl/maps/K3bpLxuZK1qMP5iG7)).

What I like about these setups is that they are easily implemented along existing totally-flush corridors but still exhibit some upsides of the Michigan Left-style corridors. You still have some driveways and some streets that require right-in/right-out, but not so many that you need to consciously design every major intersection with the intent to provide U-turns, resulting in an over-abundance of jughandles or bulb-outs which require massive ROW acquisition and can easily skyrocket the cost of a project.

I'm not sure, but I'm starting to think maybe complex intersections for the sake of reducing signal phases really are sometimes more trouble than they're worth.  Most of them require some kind of regulatory control other than a traffic signal, usually a left turn prohibition, and you kind of just have to trust that most people will obey that.  I started changing my mind about this after I started driving through a continuous-flow intersection on a regular basis, and noticing that people really do screw up navigating it in almost every way imaginable.

This honestly makes me wonder how many Michigan Left and/or Jughandle intersections might be better off with a plain old left turn lane and a protected-permissive left turn signal.  My other concern, though, is there still needs to be a good way to facilitate U-turns.  Often, when you're trying to make a left turn from a business, driveway, or minor side street, onto a major arterial, it's so much easier to turn right and take the next U-turn than it is to try to turn left across two directions and several lanes of traffic.  And I still can't say I've seen most places do as good of a job facilitating U-turns as New Jersey and Michigan often do on their arterial highways/major arterials.

Quote from: kernals12 on July 16, 2021, 07:54:48 PM

Quote from: renegade on July 16, 2021, 02:10:41 PM

Quote from: kernals12 on July 16, 2021, 12:29:35 PM
Left turns are the bane of traffic engineers, ruining the otherwise perfect signal precession that could guarantee drivers green lights.

But in the 60s, Michigan solved that problem by incorporating u turns into the medians of divided highways to all for left turn movements while prohibiting them from the main intersection
(https://i.imgur.com/FprxMK0.png)

Studies have shown they result in enormous improvements in safety and traffic flow. Because they also require the use of a wide median, they offer space for landscaping and stormwater drainage.

Imagine if this had become the standard design for new arterial streets all over the country, and perhaps the world. Think of all the time, money, and lives saved.

Why the f*ck aren't these everywhere?

Michigan Lefts are a pain ... trust me on this:  You don't want them everywhere.

Try experiencing life without them.

I do, life goes on without them just fine

After 20 minutes cruising down Woodward Avenue you are about 6 miles ahead of the guy cruising down US 192 in Kissimmee.

https://www.youtube.com/watch?v=FBIR0z5U82M

Quote from: tradephoric on August 18, 2021, 12:38:23 AM
After 20 minutes cruising down Woodward Avenue you are about 6 miles ahead of the guy cruising down US 192 in Kissimmee.

https://www.youtube.com/watch?v=FBIR0z5U82M

US 192 is an orange-picked example; loads of wide intersections, lots more tourist traffic, ginormous distractions, and no timing of lights (something Michigan does well at).

Kissimmee is the worst type of example because it excels at...cheap T-shirt shops and lots of timeshares. Pretty sure putting in a bunch of Michigan Lefts there would just create more uncontrolled U-turns into what appears to be much more traffic for which traffic light timing is an afterthought.

In regards to Florida, they originally had plans to build a Median U-turn at Rinehart Rd & Co Rd 46A as part of the I-4 "Beyond the Ultimate" project.  It sounds like that project is getting scaled back/delayed so we will see if they actually build it or not.  Here was an aerial rendering of the intersection they had originally planned:

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fi4ultimate.com%2Fbtu-emailblasts%2F2018-02%2FCR46A_2017-04-20-mid-block.jpg&hash=df1d67433fabd5ca1bdda5eb329faf9b113d8f6c)

Also, it looks like Pinellas County leaders are considering a Median U-turn at Gulf to Bay Boulevard and Belcher Road.  They were receiving public input on the plan back in September of last year.  Here is a rendering to that project:

County to take traffic solution for Gulf to Bay intersection on test drive
https://www.tbnweekly.com/clearwater_beacon/article_b73b2996-f84f-11ea-875c-cb2ab038a18b.html

(https://bloximages.newyork1.vip.townnews.com/tbnweekly.com/content/tncms/assets/v3/editorial/5/ea/5ea904c8-f850-11ea-adf0-f7ddbec28d89/5f626349b8d62.image.png?resize=750%2C522)

Found a youtube video that includes a model of the Gulf to Bay Boulevard Median U-turn that is being considered:

https://www.youtube.com/watch?v=UJ6vTAhPPPM

Quote from: Ned Weasel on July 23, 2021, 06:49:46 AM

Quote from: jakeroot on July 16, 2021, 08:22:38 PM
Or is a five lane road with TWLTL sufficient?

I'd really rather move away from the undivided five-laner.  I realize Michigan Lefts take up huge amounts of space and make them infeasible in most places, but, as for the rest of the road design, I'd much rather see a raised median and with the only unprotected cross traffic being well spaced left turns from the arterial.  I'd rather see everything else be RIRO except at signalized intersections.

Quote

I think the point Ned Weasel is making is very sound.  I regularly drive on a suburban arterial between home and my son's school.  This is a divided arterial with three lanes in each direction, so it's busy and traffic moves fast.  (Speed limit is now 35, but used to be 40 and one can comfortably go 50 here.)  While there are some signals on the corridor, most of the corridor intersects with smaller streets at T-intersections, where the smaller street is facing a stop sign.  It is certainly fine to have a left turn lane and median breaks on this corridor to allow folks on the main street to turn left onto the small streets.  But it is awful when folks on the small street try to make a left onto the arterial without the assistance of a signal.  There is often never a gap big enough in both directions of traffic to make this turn safely!  I'm constantly dodging folks who are making these lefts and at times either blocking the left lane while waiting for a gap in opposite traffic or coming in with very little gap room making me take evasive maneuvers.  This is really a street where side street traffic should not be forced to make a right and then a u-turn at the next opening, it would be better for everyone.

It should be said, although it's probably apparent to those on this thread, but traffic making a left or a u-turn on the main street without a signal only need to find a gap in one direction of traffic (opposing traffic).  Traffic making a left from the side street need a gap with all cross traffic in the closer direction and at least the left lane in the other direction of cross traffic.  As the signals are not timed very well here, there is a very small time when you have such a gap in both directions of the arterial traffic.  IMO, side street lefts need to be prohibited at non-signalized intersections on such a corridor like this.

And if we take Ned Weasel's idea to a hypothetical rural 4-lane road, you don't really need Michigan lefts at all.  The small amount of traffic that wants side street lefts will simply make a regular u-turn at the next opportunity.  No special road design necessary, unless the roadway has large truck traffic.

Quote from: mrsman on January 16, 2022, 04:47:09 PM
I think the point Ned Weasel is making is very sound.  I regularly drive on a suburban arterial between home and my son's school.  This is a divided arterial with three lanes in each direction, so it's busy and traffic moves fast.  (Speed limit is now 35, but used to be 40 and one can comfortably go 50 here.)  While there are some signals on the corridor, most of the corridor intersects with smaller streets at T-intersections, where the smaller street is facing a stop sign.  It is certainly fine to have a left turn lane and median breaks on this corridor to allow folks on the main street to turn left onto the small streets.  But it is awful when folks on the small street try to make a left onto the arterial without the assistance of a signal.  There is often never a gap big enough in both directions of traffic to make this turn safely!  I'm constantly dodging folks who are making these lefts and at times either blocking the left lane while waiting for a gap in opposite traffic or coming in with very little gap room making me take evasive maneuvers.  This is really a street where side street traffic should not be forced to make a right and then a u-turn at the next opening, it would be better for everyone.

It should be said, although it's probably apparent to those on this thread, but traffic making a left or a u-turn on the main street without a signal only need to find a gap in one direction of traffic (opposing traffic).  Traffic making a left from the side street need a gap with all cross traffic in the closer direction and at least the left lane in the other direction of cross traffic.  As the signals are not timed very well here, there is a very small time when you have such a gap in both directions of the arterial traffic.  IMO, side street lefts need to be prohibited at non-signalized intersections on such a corridor like this.

And if we take Ned Weasel's idea to a hypothetical rural 4-lane road, you don't really need Michigan lefts at all.  The small amount of traffic that wants side street lefts will simply make a regular u-turn at the next opportunity.  No special road design necessary, unless the roadway has large truck traffic.

I have three issues with raised median corridors, although I will admit they are relatively minor.

One, they require fairly significant ROW acquisition at key points along the corridor. Regular non-raised-median corridors do not require the construction of dedicated U-turn points; although three-lane-each-direction raised-median corridors may not require addition widening for U-turns, it may be required at any points where semi trucks are expected to do U-turns. Raised median corridors without three lanes in each direction will logically require widening at the U-turn points, which may be expensive.

Two, they tend to congregate traffic. While the overall corridor may have fewer conflict points as a result of the "untying" of certain junctions, it does make the primary intersections busier and also makes them even more complicated. Consider many of the arterial roads in Orange County, California, where every major intersection will have double left turns and permitted U-turns; the U-turns may not have been required (i.e. "no U-turn" signs could have been installed) along a two-way left turn lane corridor, and steady right green "filter" arrows could be used during the perpendicular left turn phase (they cannot be at junctions with permitted U-turns, or at least shouldn't be).

Three, raised median corridors ultimately require someone to cross (or use) every lane of traffic to make a left turn: traffic first turns right, either into the right lane and then changing lanes, or directly into the far lane; second, they enter the left turn/U-turn lane; third, they perform the U-turn, which requires the clearance of every oncoming lane (generally). Corridors without raised medians only require the clearance of traffic to the left and center turn lane, as you can enter the center turn lane and then merge into the inside lane of the other direction. This issue is certainly geographic; I recognize some states do ban this maneuver. In Washington, it is fully legislated and legal (RCW 46.61.290), and you can drive in the center turn lane for up to 300 feet to merge. Traffic here is well-trained in doing this, even (ironically) to the extent of using oncoming lanes of traffic (i.e. not a center turn lane) to merge.

I would be willing to overlook the first two issues if the third issue didn't exist. For example, if I lived in a state where I wasn't also allowed to turn into the center turn lane (as opposed to just from it, to turn off the main road), I would find turning left onto busy roads to be extremely frustrating and may not even try (instead turning right and doing my own U-turn). In addition to that, corridors without any center lane (except major intersections) may also benefit from roundabouts, which may not require any interim widening, although my first issue above does become dramatically more pronounced along these kinds of corridors.

Quote from: kernals12 on July 16, 2021, 07:54:48 PM

Quote from: renegade on July 16, 2021, 02:10:41 PM

Quote from: kernals12 on July 16, 2021, 12:29:35 PM
Left turns are the bane of traffic engineers, ruining the otherwise perfect signal precession that could guarantee drivers green lights.

But in the 60s, Michigan solved that problem by incorporating u turns into the medians of divided highways to all for left turn movements while prohibiting them from the main intersection
(https://i.imgur.com/FprxMK0.png)

Studies have shown they result in enormous improvements in safety and traffic flow. Because they also require the use of a wide median, they offer space for landscaping and stormwater drainage.

Imagine if this had become the standard design for new arterial streets all over the country, and perhaps the world. Think of all the time, money, and lives saved.

Why the f*ck aren't these everywhere?

Michigan Lefts are a pain ... trust me on this:  You don't want them everywhere.

Try experiencing life without them.

I'd love to!

Quote from: Revive 755 on July 16, 2021, 10:17:06 PM

Quote from: thspfc on July 16, 2021, 01:48:44 PM
The fact that they require a larger median is a negative, not a positive.

MO 141 in Fenton (https://goo.gl/maps/WK6nabosUMA9d4hh7) doesn't have a wide median for its Michigan left. (https://goo.gl/maps/CiQNe58BKJUNRLDH7)

Nor do the medians appear wide (https://goo.gl/maps/GSLzAnPLkwJgRJ3t8) for the one in Fishers, IN (https://goo.gl/maps/31EHAmeLx1e4Pw278)

These are silly.  They still require a signalized left turn, add more signals into a busy, congested area and require a lot of area to the right of the right lane for trucks to make the turn.  Then when in the turnaround area they're going to have to deal with a big blind spot getting back into the traffic lane.

Problems with Michigan Lefts

• Require turning right to go left, which is confusing for drivers because random intersections require you to approach in the right lane to go left
• Require weaving right after turning in order to get in the left lane to perform the U turn
• Require a U turn (without protection) as part of the operation
• Consume land in areas that it may be expensive or hard to acquire

The one area I will grant the Michigan left as a superior design is some rural freeway intersections, in that case land is usually available, one road can maintain full traffic flow at highway speed, and the other road traffic can go right in all cases (which is usually safer as only one set of lanes is involved) then wait in a separate area for a U Turn. For roads that are a T junction no cross traffic at all is needed which is a plus.

Quote from: HighwayStar on January 24, 2022, 07:48:57 PM
Problems with Michigan Lefts

• Require turning right to go left, which is confusing for drivers because random intersections require you to approach in the right lane to go left
• Require weaving right after turning in order to get in the left lane to perform the U turn
• Require a U turn (without protection) as part of the operation
• Consume land in areas that it may be expensive or hard to acquire

The one area I will grant the Michigan left as a superior design is some rural freeway intersections, in that case land is usually available, one road can maintain full traffic flow at highway speed, and the other road traffic can go right in all cases (which is usually safer as only one set of lanes is involved) then wait in a separate area for a U Turn. For roads that are a T junction no cross traffic at all is needed which is a plus.

I don't see where any of this is a problem. Turning right, going up to the U-turn and turning around to make a left turn is a heck of a lot easier than you are making it out to be. There is a traffic light at the U-turn most of the time for one thing and another it doesn't confuse anyone. What do you mean U-turn without protection?

Quote from: Flint1979 on January 25, 2022, 01:48:07 PM

Quote from: HighwayStar on January 24, 2022, 07:48:57 PM
Problems with Michigan Lefts

• Require turning right to go left, which is confusing for drivers because random intersections require you to approach in the right lane to go left
• Require weaving right after turning in order to get in the left lane to perform the U turn
• Require a U turn (without protection) as part of the operation
• Consume land in areas that it may be expensive or hard to acquire

The one area I will grant the Michigan left as a superior design is some rural freeway intersections, in that case land is usually available, one road can maintain full traffic flow at highway speed, and the other road traffic can go right in all cases (which is usually safer as only one set of lanes is involved) then wait in a separate area for a U Turn. For roads that are a T junction no cross traffic at all is needed which is a plus.

I don't see where any of this is a problem. Turning right, going up to the U-turn and turning around to make a left turn is a heck of a lot easier than you are making it out to be. There is a traffic light at the U-turn most of the time for one thing and another it doesn't confuse anyone. What do you mean U-turn without protection?

Is it a "problem?"  No, but it's just a pain the butt.  I understand why under certain circumstances, like HighwayStar's "rural freeway intersections," they make sense.  But otherwise I would much rather just turn left to go left than turn right, switch lanes, and make a U-turn to go left.

Or better yet, I would rather go straight than turn right, switch lanes, make a U-turn, and then turn right to go straight.

Michigan Lefts maximize the green band and allow for impressive travel time runs along the major corridor.  Where else can you drive for nearly an hour and make it through 109 consecutive green lights without getting stopped?  And it's second nature making a left turn at a Michigan left once you are accustomed to it. 

https://www.youtube.com/watch?v=6823U0XJpDo

Quote from: Flint1979 on January 25, 2022, 01:48:07 PM

Quote from: HighwayStar on January 24, 2022, 07:48:57 PM
Problems with Michigan Lefts

• Require turning right to go left, which is confusing for drivers because random intersections require you to approach in the right lane to go left
• Require weaving right after turning in order to get in the left lane to perform the U turn
• Require a U turn (without protection) as part of the operation
• Consume land in areas that it may be expensive or hard to acquire

The one area I will grant the Michigan left as a superior design is some rural freeway intersections, in that case land is usually available, one road can maintain full traffic flow at highway speed, and the other road traffic can go right in all cases (which is usually safer as only one set of lanes is involved) then wait in a separate area for a U Turn. For roads that are a T junction no cross traffic at all is needed which is a plus.

I don't see where any of this is a problem. Turning right, going up to the U-turn and turning around to make a left turn is a heck of a lot easier than you are making it out to be. There is a traffic light at the U-turn most of the time for one thing and another it doesn't confuse anyone. What do you mean U-turn without protection?

The Michigan Lefts I have encountered never had a light at the U turn.
And its easy if you have 1 lane, but when you have 2 or more now there is a weaving problem you have to account for.
And again, even if it is an equal effort, it is considerably more difficult for the driver to know which lane to be in as they approach the intersection, the same reason Jersey Jug handles are bad.

Lights are not needed at the less-busy U turns. Especially if the mainline lights are already given signal progression. Such progression gives a green band for mainline traffic, which usually results in sufficient gaps to make the U turn when the mainline signals are red, or even before they turn red.

Quote from: HighwayStar on January 25, 2022, 03:26:55 PM
And its easy if you have 1 lane, but when you have 2 or more now there is a weaving problem you have to account for.

Agreed with this. Accessing the U-turn point requires merging all the way left to the inside, and then turning across traffic much like you would at a regular left turn...just slower.

Quote from: HighwayStar on January 25, 2022, 03:26:55 PM

Quote from: Flint1979 on January 25, 2022, 01:48:07 PM

Quote from: HighwayStar on January 24, 2022, 07:48:57 PM
Problems with Michigan Lefts

• Require turning right to go left, which is confusing for drivers because random intersections require you to approach in the right lane to go left
• Require weaving right after turning in order to get in the left lane to perform the U turn
• Require a U turn (without protection) as part of the operation
• Consume land in areas that it may be expensive or hard to acquire

The one area I will grant the Michigan left as a superior design is some rural freeway intersections, in that case land is usually available, one road can maintain full traffic flow at highway speed, and the other road traffic can go right in all cases (which is usually safer as only one set of lanes is involved) then wait in a separate area for a U Turn. For roads that are a T junction no cross traffic at all is needed which is a plus.

I don't see where any of this is a problem. Turning right, going up to the U-turn and turning around to make a left turn is a heck of a lot easier than you are making it out to be. There is a traffic light at the U-turn most of the time for one thing and another it doesn't confuse anyone. What do you mean U-turn without protection?

The Michigan Lefts I have encountered never had a light at the U turn.
And its easy if you have 1 lane, but when you have 2 or more now there is a weaving problem you have to account for.
And again, even if it is an equal effort, it is considerably more difficult for the driver to know which lane to be in as they approach the intersection, the same reason Jersey Jug handles are bad.

Which ones have you encountered? Here's just one example at Big Beaver and Rochester Road in Troy. https://www.google.com/maps/@42.563072,-83.1260508,3a,26.9y,4.21h,94.22t/data=!3m6!1e1!3m4!1sUHYjglcGTrtya_fYxe5tgw!2e0!7i16384!8i8192

The less busy intersections probably won't have a light but the busier one's will. It's easy if you have more than one lane, you turn, move over to the far left lane, turn around and you've made your left turn. How is it difficult for the driver to know which lane to be in? https://www.google.com/maps/@42.5629481,-83.1271592,143m/data=!3m1!1e3

But you will find them along streets all over the Metro Detroit area and they have done fine for over 60 years.

I take it you guys just aren't familiar with them on a regular basis. You go through this with people about roundabouts too. Michigan left turns increase traffic flow and reduces accidents. Michigan is still building them where needed too like the US-131 project in Three Rivers last year. It also eliminates a left turn light as well. The only disadvantage is the extra distance a driver has to drive.

In 2019, Elon Musk predicted there would be a million robo taxi's on the road by the end of 2020.  That prediction did not come through.  Now in last night's conference call Musk predicted that they would achieve Full Self-Driving in 2022.

"My personal guess is that we'll achieve Full Self-Driving this year,"  he said. "I would be shocked if we do not achieve Full Self-Driving safer than a human this year. I would be shocked."

Of course juxtaposing that prediction to how much Tesla FSD 10.8.1 currently struggles through a Michigan Left, you really question how attainable Full Self Driving is going to be.  I feel like FSD is always going to be just a "few years out".

https://www.youtube.com/watch?v=-SK48YpIsPI

Quote from: Flint1979 on January 27, 2022, 06:57:08 AM
I take it you guys just aren't familiar with them on a regular basis. You go through this with people about roundabouts too. Michigan left turns increase traffic flow and reduces accidents. Michigan is still building them where needed too like the US-131 project in Three Rivers last year. It also eliminates a left turn light as well. The only disadvantage is the extra distance a driver has to drive.

People don't like Michigan lefts for the same reason they don't like roundabouts.  While sure it increases traffic flow, most drivers just want to go straight without making too many decisions.  So when people have to sit at a light for a couple of cycles, what they WANT is to sit at the light less, NOT a roundabout that they then have to navigate.  (I am not saying this is a rational thought.)

Quote from: tradephoric on January 27, 2022, 07:31:50 AM
In 2019, Elon Musk predicted there would be a million robo taxi's on the road by the end of 2020.  That prediction did not come through.  Now in last night's conference call Musk predicted that they would achieve Full Self-Driving in 2022.

"My personal guess is that we'll achieve Full Self-Driving this year,"  he said. "I would be shocked if we do not achieve Full Self-Driving safer than a human this year. I would be shocked."

Of course juxtaposing that prediction to how much Tesla FSD 10.8.1 currently struggles through a Michigan Left, you really question how attainable Full Self Driving is going to be.  I feel like FSD is always going to be just a "few years out".

https://www.youtube.com/watch?v=-SK48YpIsPI

Elon Musk routinely makes predictions on all sorts of things that fall laughably short of reality.

Quote from: Flint1979 on January 27, 2022, 06:57:08 AM
I take it you guys just aren't familiar with them on a regular basis. You go through this with people about roundabouts too. Michigan left turns increase traffic flow and reduces accidents. Michigan is still building them where needed too like the US-131 project in Three Rivers last year. It also eliminates a left turn light as well. The only disadvantage is the extra distance a driver has to drive.

No, they numerous other disadvantages in terms of land required, weaving, and the turn right to go left conflict which dooms them to being inferior in most applications.

Good golly, the monster is in OH now.
https://goo.gl/maps/AJ57VTaZUQQXhbgj8
Those ugly trusses on Orlando's Orange Blossom Trail exist someplace else.

Quote from: Flint1979 on January 27, 2022, 06:57:08 AM
I take it you guys just aren't familiar with them on a regular basis. You go through this with people about roundabouts too. Michigan left turns increase traffic flow and reduces accidents. Michigan is still building them where needed too like the US-131 project in Three Rivers last year. It also eliminates a left turn light as well. The only disadvantage is the extra distance a driver has to drive.

I think roundabouts are a little different. You can do everything, turns wise, at a single roundabout, whereas a Michigan left turn has at least three intersections, sometimes more, to allow all traffic to perform the necessary maneuvers. Requiring the navigation of more than one intersection to complete a single maneuver is an inherently foreign practice for the vast majority of people in this country.

Quote from: jakeroot on January 27, 2022, 01:33:28 PM

Quote from: Flint1979 on January 27, 2022, 06:57:08 AM
I take it you guys just aren't familiar with them on a regular basis. You go through this with people about roundabouts too. Michigan left turns increase traffic flow and reduces accidents. Michigan is still building them where needed too like the US-131 project in Three Rivers last year. It also eliminates a left turn light as well. The only disadvantage is the extra distance a driver has to drive.

I think roundabouts are a little different. You can do everything, turns wise, at a single roundabout, whereas a Michigan left turn has at least three intersections, sometimes more, to allow all traffic to perform the necessary maneuvers. Requiring the navigation of more than one intersection to complete a single maneuver is an inherently foreign practice for the vast majority of people in this country.

I will add that with a roundabout the convention of "get in the left lane to go left" holds, while that does not hold for jug handles or Michigan left. That is a significant difference.
That said I also hate roundabouts.

Quote from: jakeroot on January 27, 2022, 01:33:28 PM

Quote from: Flint1979 on January 27, 2022, 06:57:08 AM
I take it you guys just aren't familiar with them on a regular basis. You go through this with people about roundabouts too. Michigan left turns increase traffic flow and reduces accidents. Michigan is still building them where needed too like the US-131 project in Three Rivers last year. It also eliminates a left turn light as well. The only disadvantage is the extra distance a driver has to drive.

I think roundabouts are a little different. You can do everything, turns wise, at a single roundabout, whereas a Michigan left turn has at least three intersections, sometimes more, to allow all traffic to perform the necessary maneuvers. Requiring the navigation of more than one intersection to complete a single maneuver is an inherently foreign practice for the vast majority of people in this country.

I'm talking about the people that complain when one is being put in and refuse to learn how to use one.

Quote from: HighwayStar on January 27, 2022, 10:25:02 AM

Quote from: Flint1979 on January 27, 2022, 06:57:08 AM
I take it you guys just aren't familiar with them on a regular basis. You go through this with people about roundabouts too. Michigan left turns increase traffic flow and reduces accidents. Michigan is still building them where needed too like the US-131 project in Three Rivers last year. It also eliminates a left turn light as well. The only disadvantage is the extra distance a driver has to drive.

No, they numerous other disadvantages in terms of land required, weaving, and the turn right to go left conflict which dooms them to being inferior in most applications.

So what? Michigan planned their roads to be this way. Taking up more land to build these roads isn't that much of a disadvantage. These roads were built before development started so how much land they take up doesn't mean much.

Quote from: SEWIGuy on January 27, 2022, 08:48:36 AM

Quote from: Flint1979 on January 27, 2022, 06:57:08 AM
I take it you guys just aren't familiar with them on a regular basis. You go through this with people about roundabouts too. Michigan left turns increase traffic flow and reduces accidents. Michigan is still building them where needed too like the US-131 project in Three Rivers last year. It also eliminates a left turn light as well. The only disadvantage is the extra distance a driver has to drive.

People don't like Michigan lefts for the same reason they don't like roundabouts.  While sure it increases traffic flow, most drivers just want to go straight without making too many decisions.  So when people have to sit at a light for a couple of cycles, what they WANT is to sit at the light less, NOT a roundabout that they then have to navigate.  (I am not saying this is a rational thought.)

What I meant is you get the same argument regarding roundabouts.

Quote from: Flint1979 on January 27, 2022, 05:38:18 PM

Quote from: jakeroot on January 27, 2022, 01:33:28 PM

Quote from: Flint1979 on January 27, 2022, 06:57:08 AM
I take it you guys just aren't familiar with them on a regular basis. You go through this with people about roundabouts too. Michigan left turns increase traffic flow and reduces accidents. Michigan is still building them where needed too like the US-131 project in Three Rivers last year. It also eliminates a left turn light as well. The only disadvantage is the extra distance a driver has to drive.

I think roundabouts are a little different. You can do everything, turns wise, at a single roundabout, whereas a Michigan left turn has at least three intersections, sometimes more, to allow all traffic to perform the necessary maneuvers. Requiring the navigation of more than one intersection to complete a single maneuver is an inherently foreign practice for the vast majority of people in this country.

I'm talking about the people that complain when one is being put in and refuse to learn how to use one.

I think people complain about change in general. But I would still argue that roundabouts are easier to grasp, especially for people not from the area. If people have to 'take a left', most people expect to be able to simply make a left, not a right turn, then a U-turn, then go straight.

Quote from: Flint1979 on January 27, 2022, 05:44:00 PM
Michigan planned their roads to be this way. Taking up more land to build these roads isn't that much of a disadvantage. These roads were built before development started so how much land they take up doesn't mean much.

That's not a very helpful point. The ROW along these corridors are basically twice the width of the standard arterial in my area; most roads don't go beyond about 100'-120'.

Quote from: jakeroot on January 28, 2022, 08:23:11 PM
That's not a very helpful point. The ROW along these corridors are basically twice the width of the standard arterial in my area; most roads don't go beyond about 100'-120'.

This (https://www.google.com/maps/@42.6526593,-71.3102856,3a,75y,315.91h,70.77t/data=!3m6!1e1!3m4!1sWEUGAj4b3PDJ8aKthLuAcQ!2e0!7i16384!8i8192), which is not currently a median U-turn (it's currently authorized vehicles only) but could easily become one, is about 120 feet wide, and it's much narrower at points other than the U-turn itself.

The world if Michigan Lefts were the norm
(https://i.imgur.com/O6Xo7hh.jpg)

Quote from: 1 on January 28, 2022, 09:20:07 PM

Quote from: jakeroot on January 28, 2022, 08:23:11 PM
That's not a very helpful point. The ROW along these corridors are basically twice the width of the standard arterial in my area; most roads don't go beyond about 100'-120'.

This (https://www.google.com/maps/@42.6526593,-71.3102856,3a,75y,315.91h,70.77t/data=!3m6!1e1!3m4!1sWEUGAj4b3PDJ8aKthLuAcQ!2e0!7i16384!8i8192), which is not currently a median U-turn (it's currently authorized vehicles only) but could easily become one, is about 120 feet wide, and it's much narrower at points other than the U-turn itself.

My 100'-120' example was an eight lane road, with three lanes each direction and a double left turn. The vast majority of roads aren't much wider than two lanes and a center turn lane (60 to 70 feet).

My point is that it's hard to create Michigan U-turn corridors outside of Detroit because the ROW acquisition required to do it properly (left on red, no bulb-outs) would be astronomical. They would never be more than a novelty here and there.

I'd like to hear some truck drivers weigh in on this.  And I'm sure there must be others like myself who have been nailed by a semi completing a Michigan left.  And I was on the right shoulder here (https://www.google.com/maps/@42.8881752,-85.5687768,3a,75y,90t/data=!3m7!1e1!3m5!1sWwjzqa0Xks7X1bqLSJ1-7g!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3DWwjzqa0Xks7X1bqLSJ1-7g%26cb_client%3Dmaps_sv.tactile.gps%26w%3D203%26h%3D100%26yaw%3D58.675774%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192).  He said he couldn't see me and I'm sure he couldn't.  I don't think there's any way after turning their cab to the left with the trailer angled behind them that they can see traffic 2 0r 3 lanes behind them to the right (even though seeing traffic in the left lane would be the biggest problem).  There is absolutely nothing safe about Michigan lefts!

Quote from: jakeroot on January 28, 2022, 08:23:11 PM

Quote from: Flint1979 on January 27, 2022, 05:38:18 PM

Quote from: jakeroot on January 27, 2022, 01:33:28 PM

Quote from: Flint1979 on January 27, 2022, 06:57:08 AM
I take it you guys just aren't familiar with them on a regular basis. You go through this with people about roundabouts too. Michigan left turns increase traffic flow and reduces accidents. Michigan is still building them where needed too like the US-131 project in Three Rivers last year. It also eliminates a left turn light as well. The only disadvantage is the extra distance a driver has to drive.

I think roundabouts are a little different. You can do everything, turns wise, at a single roundabout, whereas a Michigan left turn has at least three intersections, sometimes more, to allow all traffic to perform the necessary maneuvers. Requiring the navigation of more than one intersection to complete a single maneuver is an inherently foreign practice for the vast majority of people in this country.

I'm talking about the people that complain when one is being put in and refuse to learn how to use one.

I think people complain about change in general. But I would still argue that roundabouts are easier to grasp, especially for people not from the area. If people have to 'take a left', most people expect to be able to simply make a left, not a right turn, then a U-turn, then go straight.

Quote from: Flint1979 on January 27, 2022, 05:44:00 PM
Michigan planned their roads to be this way. Taking up more land to build these roads isn't that much of a disadvantage. These roads were built before development started so how much land they take up doesn't mean much.

That's not a very helpful point. The ROW along these corridors are basically twice the width of the standard arterial in my area; most roads don't go beyond about 100'-120'.

Uh it's not like it's something new, if you've drove in Michigan on a regular basis you'd be used to them, not the other way around. They are not that hard to get used to and as far as the extra ROW that doesn't make much of a difference.

The width of the median on these streets is about 25-30 feet it's not that big of a deal really and Michigan left turns. The only disadvantage really is that you have to drive an extra half mile to make a left turn. Michigan left's eliminate the need for a left turn light increasing the green light for through traffic, reduces left turn accidents, reduces the number of different traffic light phases increasing traffic flow. They aren't just in the Detroit area either they are all over the state.

Here's an example about 6 miles from my house that you HAVE to make the Michigan left to continue on Freeland Road.
https://www.google.com/maps/@43.5232749,-83.9757339,561m/data=!3m1!1e3

I want someone to defend me as much as Flint defends anything road related in Michigan.

^ Bring up potholes. I bet Flint won't have much good to say about MI then.

I don't have good things to say about Michigan really at all. When are they going to widen US-23 between Flint and the Ohio line? When are they going to widen I-94 pretty much through the entire state?

There are the same or higher traffic volumes on the four lane stretch of US-23 as there is the eight lane stretch of I-75 between Flint and Saginaw. Then I-75 itself narrows down to two lanes in each direction between MM 115 and 111.

For years I was wondering when they were finally going to replace all the old US-10 signs in Detroit after the Lodge Freeway had become M-10 instead of US-10 but into the 2000's there were still US-10 signs up and US-10 hasn't entered Detroit since the mid 1980's.

I don't get what the big deal about the width of the median of these streets is though. So it's an extra 30 feet that really isn't much of a big deal.

Oh when will they tear up the rest of M-58 and repave it? The one way stretch along State Street is in bad shape.

Quote from: Flint1979 on January 29, 2022, 07:44:46 AM
Uh it's not like it's something new, if you've drove in Michigan on a regular basis you'd be used to them, not the other way around. They are not that hard to get used to and as far as the extra ROW that doesn't make much of a difference.

I live in Washington State, mostly around people who come from other western states and Asia. No one here is used to Michigan U-turn corridors or the idea of "right, then U-turn to go left". So yes, it's basically something new.

Widening an arterial to 140 to 160 feet in width (average Michigan U-turn corridor width) would be laughably expensive and destructive. Most arterials around here have development right up to the edges, and the widest they ever really get is 100 to 120 feet; widening this corridor (https://goo.gl/maps/1YwgKf2aynsMMtz19) or this corridor (https://goo.gl/maps/YX3ysYz5wwJLTgna6) (both already quite wide by suburban Seattle standards) to 140 to 160 feet ROW would literally be impossible. The most you'll ever get is an extra lane here, a double turn lane there, or a roundabout.

This all said, it's not unusual to find partial U-turn corridors in parts of the Seattle area, but they are not Michigan style. Canyon Road in Puyallup (https://goo.gl/maps/ysti1fyZ9tnbpoUX7), a good hour south of Seattle, only allows left turns onto the corridor at signals -- all other movements are handled by right turns and/or U-turns. In general, this corridor runs very well; the green-time is coordinated based on time-of-day, and it handles tens of thousands of cars per day, easy. But it's not perfect: the major intersections still all permit left turns as the U-turns are very tight and cannot accommodate either (a) large volumes of vehicles nor (b) semi trucks, a very common vehicle along this corridor thanks to the many factories in the area. So the U-turns are reserved only for movements to/from minor roads. Redesigning this corridor to a level where every intersection was straight or right, and every movement was handled by U-turns, would be outrageously expensive and destructive.

Quote from: tradephoric on January 27, 2022, 07:31:50 AM
Of course juxtaposing that prediction to how much Tesla FSD 10.8.1 currently struggles through a Michigan Left, you really question how attainable Full Self Driving is going to be.  I feel like FSD is always going to be just a "few years out".

https://www.youtube.com/watch?v=-SK48YpIsPI

I've never actually seen a video of a Tesla in FSD mode before. That's scary as shit. The video creator is clearly familiar with the weird behavior the car exhibits and so he can step in and baby it at the appropriate times, but the car drives kind of like a drunk person and does erratic stuff like taking up two lanes. I would hate to be around a car where the driver was using that technology, because I have no idea when it's going to glitch out and do something dumb.

Quote from: jakeroot on January 30, 2022, 12:22:00 AM

Quote from: Flint1979 on January 29, 2022, 07:44:46 AM
Uh it's not like it's something new, if you've drove in Michigan on a regular basis you'd be used to them, not the other way around. They are not that hard to get used to and as far as the extra ROW that doesn't make much of a difference.

I live in Washington State, mostly around people who come from other western states and Asia. No one here is used to Michigan U-turn corridors or the idea of "right, then U-turn to go left". So yes, it's basically something new.

Widening an arterial to 140 to 160 feet in width (average Michigan U-turn corridor width) would be laughably expensive and destructive. Most arterials around here have development right up to the edges, and the widest they ever really get is 100 to 120 feet; widening this corridor (https://goo.gl/maps/1YwgKf2aynsMMtz19) or this corridor (https://goo.gl/maps/YX3ysYz5wwJLTgna6) (both already quite wide by suburban Seattle standards) to 140 to 160 feet ROW would literally be impossible. The most you'll ever get is an extra lane here, a double turn lane there, or a roundabout.

This all said, it's not unusual to find partial U-turn corridors in parts of the Seattle area, but they are not Michigan style. Canyon Road in Puyallup (https://goo.gl/maps/ysti1fyZ9tnbpoUX7), a good hour south of Seattle, only allows left turns onto the corridor at signals -- all other movements are handled by right turns and/or U-turns. In general, this corridor runs very well; the green-time is coordinated based on time-of-day, and it handles tens of thousands of cars per day, easy. But it's not perfect: the major intersections still all permit left turns as the U-turns are very tight and cannot accommodate either (a) large volumes of vehicles nor (b) semi trucks, a very common vehicle along this corridor thanks to the many factories in the area. So the U-turns are reserved only for movements to/from minor roads. Redesigning this corridor to a level where every intersection was straight or right, and every movement was handled by U-turns, would be outrageously expensive and destructive.

It's been around since the 1960's so it isn't something new. Just because you don't have any in your area doesn't mean it's something new. And it's not like they do this in the city of Detroit either it's in the suburbs where they do it for the most part. The only streets in the city would be like 8 Mile and Telegraph two streets that skirt the edge of the city. So this is a suburban thing not a city thing and was done before development started in the suburbs. Yeah if Seattle just now started doing something like that it wouldn't work but if they had done it before development started in the suburbs like Detroit it wouldn't have been much of a problem.

Quote from: Flint1979 on January 29, 2022, 07:56:27 AMHere's an example about 6 miles from my house that you HAVE to make the Michigan left to continue on Freeland Road.
https://www.google.com/maps/@43.5232749,-83.9757339,561m/data=!3m1!1e3

While the concept (for the side street) is similar to a Michigan Left, isn't that setup just a Restricted Crossing U-Turn (https://www.fhwa.dot.gov/publications/research/safety/09059/) (minus the normal left turns on the major road)?

Quote from: fwydriver405 on January 30, 2022, 11:11:09 AM

Quote from: Flint1979 on January 29, 2022, 07:56:27 AMHere's an example about 6 miles from my house that you HAVE to make the Michigan left to continue on Freeland Road.
https://www.google.com/maps/@43.5232749,-83.9757339,561m/data=!3m1!1e3

While the concept (for the side street) is similar to a Michigan Left, isn't that setup just a Restricted Crossing U-Turn (https://www.fhwa.dot.gov/publications/research/safety/09059/)?

It could probably be classified as that but M-84 is only setup like that for about 3 miles Freeland Road used to go through until they made it into what it is today about 20 years ago and no other roads cross it in the 3 miles. I'm not sure what the intention was for that stretch of M-84 anymore.

Quote from: Flint1979 on January 30, 2022, 07:13:16 AM
It's been around since the 1960's so it isn't something new. Just because you don't have any in your area doesn't mean it's something new. And it's not like they do this in the city of Detroit either it's in the suburbs where they do it for the most part. The only streets in the city would be like 8 Mile and Telegraph two streets that skirt the edge of the city. So this is a suburban thing not a city thing and was done before development started in the suburbs. Yeah if Seattle just now started doing something like that it wouldn't work but if they had done it before development started in the suburbs like Detroit it wouldn't have been much of a problem.

My point is just that people around here largely aren't familiar with the driving or engineering practices of Michigan. When we have to turn left, we...turn left. We don't think to do a Michigan Left unless it's expressly stated on a sign or something (R3-2 "no left" sign followed by a designated U-turn point a bit down the road...basically my Canyon Rd example).

The whole "done it before development started" point may have some truth to it, but it still requires a serious amount of forethought, especially urban-planning wise, to turn a two-lane highway into a Michigan Left corridor. My grandparents, curiously enough, have lived on my example road (Canyon Rd) since the early 1960s, when it was literally a two-lane highway with massive ditches on either side. Even then, there were stores abutting the highway that would have needed to be demolished to take the ROW from 60 feet to 140 feet (give or take). It would have been a lot easier then, but back then, Canyon wasn't a major through route -- that was WA-161, a bit further east. That would have a good corridor for some Michigan Left-style development, but even back then, I don't think there was any expectation that such capacity would have ever been necessary. I'm sure the county would love to go back 60 years and build a proper north-south high-capacity corridor, but that's obviously not going to happen.

Detroit and its suburbs absolutely did it right: set the ROW aside early, planned the Michigan Lefts along key corridors, and allowed them to flourish into the basically-freeway roads we see today. But few other municipalities have that level of forethought, and many ultimately pay the price later on -- literally, if they want to widen a roadway, since ROW acquisition is often expensive and would be extensive to build a proper Michigan Left corridor.

Quote from: jakeroot on January 30, 2022, 12:20:35 PM

Quote from: Flint1979 on January 30, 2022, 07:13:16 AM
It's been around since the 1960's so it isn't something new. Just because you don't have any in your area doesn't mean it's something new. And it's not like they do this in the city of Detroit either it's in the suburbs where they do it for the most part. The only streets in the city would be like 8 Mile and Telegraph two streets that skirt the edge of the city. So this is a suburban thing not a city thing and was done before development started in the suburbs. Yeah if Seattle just now started doing something like that it wouldn't work but if they had done it before development started in the suburbs like Detroit it wouldn't have been much of a problem.

My point is just that people around here largely aren't familiar with the driving or engineering practices of Michigan. When we have to turn left, we...turn left. We don't think to do a Michigan Left unless it's expressly stated on a sign or something (R3-2 "no left" sign followed by a designated U-turn point a bit down the road...basically my Canyon Rd example).

The whole "done it before development started" point may have some truth to it, but it still requires a serious amount of forethought, especially urban-planning wise, to turn a two-lane highway into a Michigan Left corridor. My grandparents, curiously enough, have lived on my example road (Canyon Rd) since the early 1960s, when it was literally a two-lane highway with massive ditches on either side. Even then, there were stores abutting the highway that would have needed to be demolished to take the ROW from 60 feet to 140 feet (give or take). It would have been a lot easier then, but back then, Canyon wasn't a major through route -- that was WA-161, a bit further east. That would have a good corridor for some Michigan Left-style development, but even back then, I don't think there was any expectation that such capacity would have ever been necessary. I'm sure the county would love to go back 60 years and build a proper north-south high-capacity corridor, but that's obviously not going to happen.

Detroit and its suburbs absolutely did it right: set the ROW aside early, planned the Michigan Lefts along key corridors, and allowed them to flourish into the basically-freeway roads we see today. But few other municipalities have that level of forethought, and many ultimately pay the price later on -- literally, if they want to widen a roadway, since ROW acquisition is often expensive and would be extensive to build a proper Michigan Left corridor.

So what do drivers in the Pac NW do when they want to turn left and left turns are prohibited? This  (https://www.google.com/maps/@38.5927808,-90.3019113,3a,75y,185.05h,90.18t/data=!3m6!1e1!3m4!1sKtD7IuSluK81CsZBcf0u7A!2e0!7i16384!8i8192?hl=en)is quite  (https://www.google.com/maps/@38.5810041,-90.2675304,3a,75y,46.46h,90t/data=!3m7!1e1!3m5!1sd8u--kZcftFuxxbxpPNy_g!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3Dd8u--kZcftFuxxbxpPNy_g%26cb_client%3Dmaps_sv.tactile.gps%26w%3D203%26h%3D100%26yaw%3D39.436646%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192?hl=en)common in St Louis (https://www.google.com/maps/@38.6045393,-90.2231963,3a,60y,90t/data=!3m6!1e1!3m4!1sRqDr5b0exY5jRc_mfb3v9A!2e0!7i16384!8i8192?hl=en) where I spent most of my career. Locals are used to it and know how to get around on the side streets.  I would have appreciated a Michigan Left in these cases. It did take me a while to learn how to get around with many intuitive left turns being prohibited.

The St Louis Metro also has turns that are similar to Michigan Lefts on Lindbergh (https://www.google.com/maps/@38.6486062,-90.4052452,421m/data=!3m1!1e3?hl=en). I've seen this in a few other places but it wasn't a common MODOT strategy and the turnarounds are well marked.

That last one looks more like a jughandle.

Has anyone ever tried to do a good comparison of a Michgan left with an RCUT or J-turn?

Kentucky is installing RCUTs like crazy, and they all allow left turns from the main road to the side road. What they don't allow is the straight through movement which requires crossing four lanes of traffic. They make through traffic or left-turning traffic on the side road turn right and then do a U-turn to go back to the intersection.

Of course most of these are located in rural areas with highway speed traffic on the main road, and with no traffic signals.

Quote from: skluth on January 30, 2022, 03:33:27 PM
So what do drivers in the Pac NW do when they want to turn left and left turns are prohibited?

In almost every case, left turn prohibitions are replaced by another left turn elsewhere, as opposed to a right-turn/U-turn combo.

Example 1 (https://goo.gl/maps/4amFrtbsX5TpySaJA): you cannot turn left directly into the Shell station, but you can turn left a few driveways later and then come back to the Shell.
Example 2 (https://goo.gl/maps/Zn9Tfna6sjpTX2Ga9): You cannot turn left onto Thomas (although through traffic isn't permitted at all, even along Thomas), but you can turn left either before or after this turn to reach Thomas via Dexter.
Example 3 (https://goo.gl/maps/Xck3ap6wUiGN74oW8): you cannot turn left onto Winona Ave (few people would need to make this turn), but you can make several right turns and then proceed eastbound through the intersection.
Example 4 (https://goo.gl/maps/wLnLRQhTZbrpX25s9): You cannot turn left from Mercer to 6th, but you can turn left either prior to here (at Dexter) or in a few blocks (at 5th) and then return to 6th via Harrison.

Here are some examples where left turns are prohibited from a side street:

Example 5 (https://goo.gl/maps/1vVSeGYWm5x3N64NA): you cannot turn left directly onto Pacific Hwy, but you can turn right and then make a U-turn; reaching the road would require a U-turn as well, and the signals along this stretch specifically permit them.
Example 6 (https://goo.gl/maps/5vtgm9SRVtNJ6YmC9): you cannot turn left directly onto Aurora, but you can turn right and then either make a couple more lefts, followed by a right onto Aurora, or a few rights, and then a left onto Aurora at another signal that permits it.

Quote from: hbelkins on January 30, 2022, 04:55:36 PM
Has anyone ever tried to do a good comparison of a Michgan left with an RCUT or J-turn?

Kentucky is installing RCUTs like crazy, and they all allow left turns from the main road to the side road. What they don't allow is the straight through movement which requires crossing four lanes of traffic. They make through traffic or left-turning traffic on the side road turn right and then do a U-turn to go back to the intersection.

Of course most of these are located in rural areas with highway speed traffic on the main road, and with no traffic signals.

Here's a comparison
(https://i.imgur.com/QsIAGSG.png)

YUMBLtv just designed a Michigan Left on Cities Skylines that doesn't require signalized U-turns.  The main issue i see with this design is that all U-turn traffic is dumped onto the left-most lane along the arterial making it difficult to safely merge to enter a close driveway on the right hand side of the road.  Very cool design though.
.
https://www.youtube.com/watch?v=UfpYi1s0ofk

Quote from: tradephoric on February 02, 2022, 03:42:55 PM
YUMBLtv just designed a Michigan Left on Cities Skylines that doesn't require signalized U-turns.  The main issue i see with this design is that all U-turn traffic is dumped onto the left-most lane along the arterial making it difficult to safely merge to enter a close driveway on the right hand side of the road.  Very cool design though.

I've been building Michigan Lefts for years. Rarely signalize the U-turns or even the right turns:

(https://live.staticflickr.com/65535/51858915376_6e60df16db_o.png)
Michigan U-turn Intersection (https://flic.kr/p/2n1AuNC) by Jacob Root (https://www.flickr.com/photos/62537709@N03/), on Flickr

edit: smaller road intersecting major road:

(https://live.staticflickr.com/65535/51859648815_35c2d4727a_o.png)
Michigan Left Intersection (2) (https://flic.kr/p/2n1EfQ8) by Jacob Root (https://www.flickr.com/photos/62537709@N03/), on Flickr

(https://i.imgur.com/4ImoZG1.png)

(https://i.imgur.com/crWKPGY.png)

Arizona has taken my advice with many of Phoenix's fast growing suburbs planning to implement "Arizona Parkways" which have median u-turns.

Outside of Michigan, Grant Road in Tulsa, Arizona is the best example of a full fledged Median U-Turn corridor.  Most other Michigan Left locations are just spot treatments.

Quote from: tradephoric on February 18, 2022, 02:45:53 PM
Outside of Michigan, Grant Road in Tulsa Tucson, Arizona is the best example of a full fledged Median U-Turn corridor.  Most other Michigan Left locations are just spot treatments.

ftfy

Which is honestly amazing, because Grant Road doesn't have more than a handful of Michigan Left intersections, assuming you discount all of the LI-RI-RO approaches.