Michigan Lefts

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A Michigan Left is an at-grade intersection design that replaces a traditional left turn maneuver with a right turn and a u-turn. Michigan Lefts are predominately found in the state of Michigan. Other states that have been observed to incorporate Michigan Left roadway design include Louisiana, Texas, Utah, North Carolina, and Arizona. Michigan Lefts have also been observed in Australia and Mexico.[1]


Representing Michigan Lefts OpenStreetMap

As mentioned above, the Michigan Left replaces the traditional left turn maneuver with a right turn and u-turn maneuver. Michigan Lefts in OpenStreetMap are digitally represented by (i) adding the u-turn links to the map and (ii) creating No Left Turn turn restrictions. Examples of Michigan Lefts are depicted in the table below.


MichiganLeft Intersection.PNG
To the left is an example of a Michigan Left at an intersection between two (2) divided (aka dual carriageway) roads. Note the "no left turn" restrictions at the intersection. Also note the u-turn links that are a few to several hundred feet north, south, east, and west of the intersection.
MichiganLeft Intersection dualandSingleCarriageway.PNG
To the left is an example of a Michigan Left at an intersection between a two-way (aka single-carriageway) and a divided (aka dual carriageway) road. Like the example above, there are "no left turn" restrictions at this intersection. Also note the u-turn links that are east and west of the intersection and along the divided road.

See also

References

  1. [1],Wikipedia, Michigan Left Locations