 A typical Michigan left setup. A Michigan left, sometimes known as a median U-turn[1] or median U-turn crossover,[2] is an automobile traffic maneuver in which a unidirectional U-turn and a right turn replace a prohibited left turn. The term comes from the fact that the arrangement is quite common along Michigan roads and highways, and extremely rare anywhere else in the United States. This is a file from the Wikimedia Commons, a repository of free content hosted by the Wikimedia Foundation. ...
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Interstate 80, a freeway in California with many lanes and heavy traffic. ...
Official language(s) None (English, de-facto) Capital Lansing Largest city Detroit Area Ranked 10th - Total 97,990 sq mi (253,793 km²) - Width 239 miles (385 km) - Length 491 miles (790 km) - % water 41. ...
Description
Michigan lefts occur at intersections where at least one road is a divided highway or boulevard. Left turns onto the divided highway are prohibited. Instead, drivers on roads that cross the highway are directed to turn right. Within a 1/4 mile (400 m), they queue into a designated U-turn lane in the median. When traffic clears they complete the U-turn and go back through the intersection. For additional safety purposes, the U-turn lane is designed so traffic only flows through it one-way. In the field of road transport, an intersection is a road junction where two or more roads either meet or cross at grade (they are at the same level). ...
Divided Highway is the fourteenth studio album by American rock band The Doobie Brothers, released in 2003. ...
The examples and perspective in this article or section may not represent a worldwide view. ...
On an expressway, motorway, or autobahn, the median (North American English) or central reservation (British English) is the strip of grass or the wall which separates opposing lanes of traffic. ...
It has been suggested that this article or section be merged with U-Turn. ...
Similarly, traffic on the divided highway cannot turn left at an intersection with a cross street. Instead, drivers are instructed to overshoot the intersection, go through the U-turn lane, come back to the intersection from the opposite direction and turn right.
Locations The Michigan left was initially piloted by MDOT at the intersection of 8 Mile Road (M-102) and Livernois Avenue(map) in Detroit in the early 1960s. The increase in traffic flow and reduction in accidents was so dramatic that over 700 similar intersections have been deployed throughout the state since then. The Michigan Department of Transportation (MDOT) is a government agency in the U.S. state of Michigan. ...
Eight Mile Road Exit off of I-94 Eight Mile Road forms the boundary between the city of Detroit, Michigan (and Wayne County) and Detroits northern suburbs in Oakland and Macomb Counties. ...
M-102 is a highway in the U.S. state of Michigan, running along the northern boundary of Detroit. ...
Motto: Speramus Meliora; Resurget Cineribus (We Hope For Better Things; It Shall Rise From the Ashes - this motto was adopted after the disastrous 1805 fire that devastated the city) Nickname: The Motor City and Motown Location in Wayne County, Michigan Founded Incorporated July 24, 1701 1815 County Wayne County Mayor...
The 1960s decade refers to the years from 1960 to 1969, inclusive. ...
The Michigan left is also common in New Orleans, Louisiana[citation needed], in South Korea[citation needed], and in Taiwan[citation needed]. Nickname: The Crescent City, The Big Easy, The City That Care Forgot Location in the State of Louisiana and the United States Coordinates: Country State Parish United States Louisiana Orleans Founded 1718 Mayor Ray Nagin (D) Area - City 350. ...
Pros and cons
 Two versions of signs posted along an intersecting road or street at a Michigan left intersection. Top: most commonly used; Bottom: lesser-used variant. This type of intersection configuration, as with any engineered solution to a traffic problem, carries with it certain advantages and disadvantages and has been subject to several studies. Image File history File links MichiganLeftSigns. ...
Image File history File links MichiganLeftSigns. ...
Advantages - Safety — potentially provides a major reduction in left-turn collisions and a minor reduction in merging and diverging collisions, due to the shifting of left turns outside the main intersection[2]
- Reduced travel times — Reduces the number of different traffic light phases, increasing traffic flow. Since separate phases are no longer needed for left turns, this increases green time for through traffic. The affect on turning traffic is mixed.[2]
- More options for turning — At intersections where both roads have Michigan Lefts, there is more than one way to turn left. For example it is possible to either turn right at the intersecting road, and use the U-turn to go left, or go past the intersecting road, use the U-turn on the original road, and make a right on the intersecting road. This is very useful when trying to avoid traffic lights provided there isn't a "No turn on red" sign. It also allows for an alternate path in case of a traffic-blocking incident.[original research?]
- Cost — U-turn lanes are often already present on divided highways to provide for access to businesses in the opposing direction. Hence the addition of the Michigan left turnaround is essentially free.[original research?]
- Enhanced progression — The timing of traffic signals along a highway featuring Michigan lefts is made easier by the elimination of left-turn phases both on that highway and along intersecting roadways. Thus, traffic progression through the timed signals in enhanced, contributing further to the reduction of travel times and the increased capacity of those roadways.[2]
- Fewer threats to pedestrians — Pedestrians crossing either street at an intersection featuring Michigan lefts only encounter through traffic and vehicles making right turns. The left-turning movement, having been eliminated, removes one source of potential vehicle-pedestrian conflict. However, the major roadway typically has a wider cross section, making said crossing longer.[2]
A stoplight in Mexico City. ...
Disadvantages - Confusing — since the scheme is rare outside of Michigan, it can be confusing to visitors expecting to be able to turn left from the left lane.[2]
- Inconsistent — not all intersections use the system, so drivers approaching an unfamiliar intersection do not necessarily know whether to be in right or left lane, although signage is generally placed in advance of intersections requiring such a maneuver.[original research?]
- Land use — Depending on the width of the existing median, extra land may be needed for large vehicles to make the U-turn. Additionally it may be harder to access local businesses.[2]
- Cycling - the increased number of right turns means more conflicts with bicycle lanes.[2]
- Stress — drivers may need to quickly move across several lanes of traffic when getting into or out of the U-turn, although if traffic does not permit, typically another U-turn is available within less than a mile. The need to "quickly" move across several lanes is negated, however, when making the right turn on a green light, whereby all traffic on the cross-street is stopped.
- Expense — On high traffic roads, Michigan lefts may require an additional pair of traffic lights at each of the turnarounds. This is offset, however, by the much simpler traffic signal set-up at the primary intersection, largely due to the removal of the left-turn movement and all dedicated signals and left-turn lane allowances.[original research?]
- Visibility — Drivers inching up in the right lane of a Michigan Left may block the visibility of drivers attempting to make a turn from the left lane. The problem also sometimes happens when there is a backup in an opposing Michigan Left.[original research?]
- Safety – while eliminating collisions in the intersection, traffic has to join the opposing traffic flow at the U turn in the fast lane.
On an expressway, motorway, or autobahn, the median (North American English) or central reservation (British English) is the strip of grass or the wall which separates opposing lanes of traffic. ...
This article or section should include material from Cycle path debate Segregated cycle facilities may consist of a separate road, track, path or lane that is designated for use by cyclists and from which motorised traffic is generally excluded. ...
See also Hook turn sign, Melbourne A hook turn is a special right-turn manouvre required in parts of Melbourne, Australia. ...
A typical jughandle setup, with one standard jughandle and one reverse jughandle. ...
At a superstreet, all traffic on the side road must turn right, where it can access a U-turn ramp. ...
A continuous flow intersection, also called a CFI, is an at-grade intersection that moves the turn conflict (to the left where traffic drives on the right and vice versa) out of the main intersection. ...
References - ^ North Carolina State University, Unconventional Left-Turn Lanes Reduce Traffic Accidents, Congestion, August 1, 1999
- ^ a b c d e f g h Federal Highway Administration, Alternative Intersection Treatments - Median U-Turn Crossover
North Carolina State University is a public, coeducational, extensive research university located in Raleigh, North Carolina, United States. ...
August 1 is the 213th day of the year in the Gregorian Calendar (214th in leap years), with 152 days remaining. ...
1999 (MCMXCIX) was a common year starting on Friday, and was designated the International Year of Older Persons by the United Nations. ...
The Federal Highway Administration (FHWA) is a division of the United States Department of Transportation that specializes in highway transportation. ...
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