An evacuation that sent more than two million people out of Hurricane Gustav's path last week had its challenges.

Drivers in contraflow and gas stations along the interstate ran out of fuel, exits shut down and many were caught off guard by the hours-long trek from state to state.

Mississippi transportation leaders want to learn from the experience so they can help improve emergency traffic flow next time.

"We had numerous people running out of gas, on the road, I can tell you that happened through the state," said Louis Calato, Louisiana State Trooper with Troop L based in Mandeville. "A lot of breakdowns because cars were overheating because they weren't maintained."

The way contraflow worked, as hundreds of thousands of people were evacuated from the coast of Louisiana, taking them out of the path from Hurricane Gustav. Trooper Calato said that contraflow was set up to send traffic east-bound through New Orleans, into St. Tammany and Slidell, allowing cars to travel Interstate 10 East toward Mobile, until it hit a major snag.

"We started having back-ups, problems, especially in Mobile at the tunnel where you go from a four lane to a two-lane, it was a major choking point for us," he said.

The mishap sparked wrecks for miles on end, as traffic piled up.

"As we saw this happening, we were notified by Mississippi Department of Transportation and asked to shut down that corridor heading I-10 eastbound into Bay St. Louis," said Calato.

That diverted traffic onto Interstate 59 North.

Danny Manley, Emergency Management Director for Pearl River County in Mississippi, said the I-10 shutdown was part of his state's contraflow plan. But, the major backup in Mobile was one many drivers did not expect and weren't prepared for.

As traffic backed up onto I-59, gas stations ran out of fuel, exits closed and drivers got off the interstate.

"They started pulling off and taking backroads, many got lost," said Manley. "Saturday night we had to mobilize volunteer fire departments to find these people and get them back on I-59."

Manley said they have learned many lessons from the traffic influx. Next time they may place portable toilets along the interstate so drivers don't try to exit. They will also be more media savvy.

"As events develop on the interstate we can get it out right away. If we run low on fuel in Picayune on the south end and tell everybody to get fuel on the north end," he said.

But there are some challenges that only can be resolved by evacuees, by getting ready early.

"The common sense factor. Don't leave home with half a tank of gas, no food or water and everybody needs a bathroom and get involved in contraflow. That's not the way to do it," said Manley.

He and other transportation officials will talk about what can be done to improve contraflow Wednesday morning, but hope it is a plan they will not have to use anytime soon.