A typical Michigan left setup. A Michigan left, sometimes known as a Michigan left turn or a Superstreet, is an automobile traffic maneuver in which a 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.
Michigan lefts occur at intersections where at least one road is a divided boulevard or highway. When left turns in the intersection are prohibited, drivers on major roads that cross the highway are instead directed to turn right. Within 1/4 mile, they go into a designated U-turn lane, and when traffic clears they complete the U-turn, and go back through the intersection.
Similarly, traffic on the highway does not turn left in the intersection. Instead, drivers overshoot the intersection, go into the U-turn lane, come back to the intersection and turn right.
The Michigan left was initially developed along Telegraph Road (U.S. Highway 24) and 8 Mile Road (Michigan State Highway 102) in Detroit in the 1960s, with over 700 similar intersections deployed throughout the state since then.
Advantages
- Safety - eliminates many collisions in the intersection
- Reduces traffic light phases - increases green time for through traffic, and prevents backups in left-turn lanes (which may be replaced with backups in U-turn ramps)
Disadvantages
- Stressful - drivers must quickly move across several lanes of traffic either when getting into or out of the U-turn, though separate traffic lights are sometimes provided at the U-turn ramps
- Safety - while eliminating collisions in the intersection, traffic has to join the opposing traffic flow at the U turn.
- Inconsistent - not all intersections use the system, so drivers approaching an unfamiliar intersection don't necessarily know whether to be in right or left lane
- Confusing - since the scheme is rare outside of Michigan, it is confusing to visitors, who expect to be able to turn left from the left lane
- Requires more land - Fewer lanes are needed at the intersection, but the median of one must widen for the U-turns
See also
External links
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