Contraflow lane reversal

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Contraflow lane reversal is a program designed for quick emergency evacuation of an area. Incoming highway lanes to a city are changed to outbound lanes. This doubles the number of lanes available for outbound evacuation traffic. Crossover sections are used to move outgoing traffic to these lanes. All incoming traffic is blocked until the end of the program. Usually, the term is used to refer to reversal of lanes which are normally only configured for travel in one direction; changing the configuration of reversible lanes such as for rush hour is not normally considered contraflow lane reversal.

Contraflow lane reversal is usually done to freeways and other controlled-access roadways. Use of contraflow lane reversal is generally considered to be an emergency measure only, as the contraflow lanes (and any associated ramps at interchanges) lack proper signage, signals, and other traffic control devices needed to orderly conduct traffic in the opposite direction. Generally, a significant number of police officers, or other officials, are needed to manually direct traffic during a lane reversal (especially at interchanges, where ramp traffic in the wrong direction must intersect with other roadways operating normally).

Contents 1 For use in emergency evacuation 1.1 Hurricane evacuation 1.1.1 Louisiana 1.1.2 Mississippi 1.1.3 Texas 1.1.4 Georgia 1.1.5 Florida 1.1.6 South Carolina 1.1.7 Alabama 1.2 Contraflow lane reversal in movies 2 Other uses 2.1 Sports culture 2.2 Highway reconstruction situations 2.2.1 2-lane arterials 2.2.2 Roads with four or more lanes 2.2.3 Freeways and expressways

For use in emergency evacuation

Read the article on Interstate highway for more information on facilitation of emergency evacuation plans for the United States.

Hurricane evacuation

Louisiana

Southeast Louisiana has an active program first used during evacuation for Hurricane Ivan in the summer of 2004. The program was designed to quickly evacuate the New Orleans metropolitan area and its out-lying regions through Interstates 10, 12, and 55. This, however, was a complete failure due to the lack of communication with the neighboring parishes and the "bottleneck effect" in the capital city of Baton Rouge. The normal commute time of two hours increased dramatically to 14 hours.

The plan was changed for the summer of 2005 into a phased program sponsored by the Louisiana State Police.

The Louisiana state contraflow program was activated at 4:00pm CDT on August 27, 2005, in advance of the approaching Hurricane Katrina.

Mississippi

Mississippi's contraflow plan was activated at the same time. The Mississippi program affects Interstates 55 and 59 in southern Mississippi. Contraflow along Interstate 59 continued from the Mississippi-Louisiana border, and stopped about 21 miles north near the town of Poplarville. Louisiana's program ended at 4:00pm CDT on August 28, 2005. Initial reports indicate that this activation has occurred much more smoothly than that of 2004.

Texas

Authorities in Texas activated a contraflow plan in order to evacuate Houston and other coastal cities in anticipation of the arrival of Hurricane Rita. This was done on Interstate 45 northbound to a point just over halfway to Dallas, and on Interstate 10 most of the way to San Antonio.

Georgia

Georgia has a plan to reverse Interstate 16 west to near Dublin, in order to evcuate Savannah. As with other states, it fails to go the entire way to the next Interstate highway (in this case, Interstate 75 in Macon), potentially leaving traffic backed-up where there are little or no services available to evacuees.

Florida

The Florida Turnpike and Interstate 95 parallel each other for some time along the east coast of south Florida, and the southbound lanes of at least one of them are made contraflow for major storms. Tolls are also lifted along the turnpike in the event evacuations are called for.

South Carolina

In South Carolina, Interstate 26 may be used in contraflow to evacuate Charleston, heading northwest toward Columbia.

Alabama

In Alabama, Interstate 65 may be used in contraflow to evacuate Mobile, headed northeast toward Montgomery. This has been done for both Ivan and Katrina.

Contraflow lane reversal in movies

• In the movie Deep Impact, cars that were evacuating major cities near New York and New Jersey were jammed up even though they were going south in both sides of the freeway.
• In the movie Atomic Train, people were trying to leave Denver as a precaution to the explosion of the atomic bomb that was being hauled on a train.
• In a deleted scene from the movie Independence Day, two characters (who are trying to drive to Washington D.C.) almost crash their car when the highway is suddenly opened to contraflow lane reversal.

Other uses

Sports culture

At the beginning and end of major sporting events, the center turn lanes of roads around a stadium or arena may be used to accommodate sporting event traffic. As these lanes are typically not subject to lane control, this can be considered a limited form of contraflow reversal.

Highway reconstruction situations

Sometimes when roads are being worked on and traffic is rather heavy, one lane will be blocked off but the other one however may be reversed.

2-lane arterials

A construction worker direct traffic with a sign with "STOP" on one side and "SLOW" on the other. The sign flips, and the other side proceeds. Traffic signals are also sometimes used, especially when it involves bridge construction, or any situation where a lane must be closed during times when construction crews are not at work.

Roads with four or more lanes

Roads consisting of four lanes or more will usually have two-lane two-way traffic on one half if the road needs to be reconstructed so that rush-hour traffic can flow smoothly.

Freeways and expressways

Freeways (usually 4 lanes or more) that are undergoing reconstruction reduce both sides to one lane. In some cases, they will shift traffic onto one half making it a temporary super-2 corridor. (Another technique used is treating the rightmost hard shoulder as a travel lane.) In the case of 6-lane freeways (3 in each direction), the third lane is often kept for the busier direction or the shoulder is opened up to allow for 4 lanes of traffic, but with little or no shoulder space (emergency breakdown areas are sometimes added, however). Usually, merge ramps on freeways and non-freeways with interchanges have temporary "YIELD" signs for these situations.