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The
Michigan Left
Introduction | How
it Works | History | Photos & Plans | Other
Thoughts
Often maligned, often misunderstood, the Michigan Left Turn is an
operation which causes much consternation among out-of-state drivers and
nary a second thought from locals. Developed in Michigan in 1960 (see History),
these turning set-ups exist across the entire state, from Niles to Escanaba
and from Detroit to Marquette. (Yes, the Upper Peninsula has Michigan Lefts!)
The Michigan Left was developed to avoid the interlocking left-turn movements
along divided highways. In this way, the only turning movements allowed at
such an intersection are right-hand turns. Traffic lights can be placed at
busier Michigan Left intersections if warranted. For the most heavily-used "crossovers," specialized
traffic signals may be placed to ensure traffic does not back up on the highway
waiting to turn left.
Key
Red Line - divided highway
traffic turning left onto crossroad.
Green Line - crossroad
traffic turning left onto divided highway.
How it Works
Red Line traffic on the divided
highway cannot turn left directly at the crossroad intersection. To accomplish
the left turn, the divided highway traffic moved to the left lane, continues
past the crossroad, and turns left into a "median crossover," usually placed
about 660 feet beyond the intersection. When traffic clears sufficiently,
the left turn onto the opposite direction of the divided highway is completed.
The driver then moves to the right lane and turns right onto the crossroad,
thus completing the traffic movement.
Green Line traffic on the
crossroad wishing to turn left onto the divided highway first turns right
onto that highway, moves to the left lane and turns left into the "median
crossover" approximately 660 feet from the intersection. When traffic clears
sufficiently, the left turn onto the opposite direction of the divided
highway is completed.
History of the Michigan Left Turn
The following is excerpted from the publication "The State of Michigan
Trunk Line Story," Third Edition, by Stanley D. Lingerman, P.E. Fellow
Member, August 15, 1996. From the second chapter titled "U.S. and Super
Highways," Mr. Lingerman relates just how the Michigan Left came to be:
The
Super Highway, which was originally designed for use in the Detroit area
as part of the United States Highway Program of the late 1920s, proved with
time to have some operational problems that developed from the traffic growth
following World War II.
In 1960, in order to avoid the interlocking of left-turn movements, a number
of major intersections along Telegraph Road [US-24]
in Wayne County were designed as Super Highway with directional crossovers.
The purpose of the directional crossovers was to remove the left turns from
the major intersections. The crossovers were placed in the median island about
350 feet from the cross street. Joseph Hobrla, the Department's Signal Engineer,
was dissatisfied with the traffic flow characteristics of these intersections
on Telegraph Road. He and Joseph Marlow, the District Traffic Engineer [for
the State Highway Department], decided to experiment with the westbound Eight
Mile Road[M-102] left
turn at Livernois Avenue in Detroit. A directional left-turn crossover was
constructed in the median of Eight Mile Road at a point 660 feet west of Livernois.
A traffic signal was placed on eastbound Eight Mile Road at Livernois to handle
the right-turn movement. The operation has proved to be so successful that
700 directional crossovers have been constructed on the trunk line system throughout
the state.
The Michigan Left Turn treatment continues to be implemented around the
state whenever deemed necessary to improve the flow of traffic. In the
early 1990s, for example, M-44/East
Beltline Ave in the Grand Rapids area, from I-96 northerly
to Plainfield Ave, was completely re-constructed as a divided highway,
with Michigan Left crossovers. Also in West Michigan, US-31 from
Holland to Grand Haven is slowly being upgraded to include Michigan Lefts
at the busier intersections.
Although Michigan has been using the Michigan Left treatment for over
four decades now, other states have been slow to experiment with this type
of traffic control. However, in recent years other states and municipalities have begun to implement Michigan Lefts due to shrinking transportation budgets and increasing traffic congestion. For example, the North Carolina Department of Transportation has been actively implementing Michigan Lefts as a part of their "Superstreet" program and other municipalities, such as Prescott, Arizona, are contemplating them as well.
Photos & Plans
Other Thoughts
- Experiment
in Reckless Abandon: Michigan Left - a weblog by "Cordelia" who
moved to Michigan from California and, while she loves the "greeness" of
the state, cannot understand the Michigan Left: "'They' - whoever they are
- have decided in their little pointy heads that they can't just allow
anyone to make a left turn when they want to. ... You are often forced
to go down to the next stoplight and make a u-turn and come back. Obviously
that is so much more efficient and better for traffic than just allowing
people to make a left whenever the fancy strikes them." Actually...
it is!
- On the other hand... Joe Varani, a student
at Syracuse University in New York, wishes there were more Michigan Lefts!
On his "Favorites" page, he laments about Syracuse's Erie Blvd: "It's
a large road, and at every major intersection, it seems we have to sit
at the light for about four minutes. Each direction gets its own green
light, and most times, there's a separate time for left-turns to occur.
You know what would really improve the traffic flow on Erie?" (Yep, you
guessed!) Unforunately, Joe's site is now offline!
- The North
Central Section of the Institute of Transportation Engineers (NCITE) Geometrics
Committee noted, in meeting
minutes from August 2005, that "Although committee members
noted incidents of strong public opposition to the access closures
associated with Michigan Left Turn Lanes, Howard presented data from
several states indicating fairly significant decreases in crashes."
- "Turning
Right to Go Left" or "Go Through the Light, Then Left,
Then Right" - another (short) weblog entry from "Swirlspice" summing
up the Michigan Left as "a love-it-or-hate-it gem of traffic
engineering."
- You
know you're from Michigan when.... These jokes have been
going around the Internet for years, but take a look at No. 18 on
this list...
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