Gustav Mississippi

Louisiana evacuees creep northward away from the path of Hurricane Gustav Sunday, Aug. 31, 2008, in the contraflowed southbound lane of U.S. 55 about 10 miles south of Brookhaven, Miss. The influx of evacuees into Brookhaven, the first city after the contraflow ends, caused some church-based shelters in the community to begin reaching capacity by 4:30 p.m. Sunday. (AP Photo/Adam Northam, The Daily Leader) ORG XMIT: MSBRO104

It seems to make perfect sense. When evacuations ahead of hurricanes are needed, transform all lanes of the interstate into one direction to allow as many people to get out as fast as possible – what Louisianans have come to know as contraflow.

But the reality is more complex, and a checklist of conditions must be met before the state can employ contraflow. Otherwise, attempting to put it in place can do more harm than good, state officials say, since it severely limits transportation options. That’s why it hasn’t been used since Hurricane Gustav in 2008.

With hurricane season now underway, here’s an explanation of when contraflow – involving parts of I-10, I-55 and I-59 -- can be used and the complications involved. As Rodney Mallett, spokesman for the state Department of Transportation and Development, recently said: “You can't just run up to your local grocery store and buy contraflow off the shelf.”

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72 hours in advance

The decision to use contraflow must be made a full three days in advance of employing it because of the intensive preparation required. Those preparations include blocking off hundreds of intersections and reprogramming traffic lights. Traffic control equipment such as barrels and cones must also be set out.

The task of transporting evacuees from parish pickup points must also be completed, equipment and personnel must be set up for post-storm response and there must be coordination with neighboring states.

Mandatory evacuation needed

The decision to use contraflow can only follow a mandatory evacuation order for New Orleans and the surrounding parishes – the state’s population center.

Category 3 storm

The storm approaching must be a slow-moving hurricane of at least Category 3 strength. One complicating factor recently is that hurricanes have been undergoing rapid intensification, which does not leave enough time. That was the case with Hurricane Ida in 2021.

DOTD’s explanation of contraflow sums it up this way: “In some situations, it’s far quicker to encourage citizens to evacuate rather than spend time and resources setting up contraflow.”