CONWAY - State and local officials think a first-ever plan to reverse southbound lanes on U.S. 501 for about 20 miles could make Grand Strand hurricane evacuations six or seven hours faster.

On Tuesday, Gov. Mark Sanford stopped in Horry County to unveil plans before going to Charleston and Hilton Head Island for announcements there. Hurricane season began June 1 and ends Nov. 30.

The southbound lanes of U.S. 501 will reverse in Horry County at S.C. 22 and continue into Marion County, where traffic flow will return to normal at S.C. 576, Sanford said.

Officials commended Aynor Mayor John Dawsey for allowing the town of 587 residents to be effectively divided by nonstop, one-way motor traffic during an evacuation.

"The people in Aynor will have virtually a Berlin Wall in the town," Sanford said.

Traffic leaving the beach northbound on U.S. 501 will be diverted into the southbound lanes just before S.C. 22, which will allow that traffic to go north in the northbound lanes. Motorists will not be allowed to change lanes once they are in the reversed lanes.

The reversal, the first such plan for Horry County, will continue until U.S. 501 meets S.C. 576. Traffic in the northbound lanes of U.S. 501 will be diverted to U.S. 501 Business, toward Dillon, while traffic in the reversed lanes will be moved back into the northbound lanes of U.S. 501 and onto S.C. 576 to Florence.

The reversals could trim overall traffic travel time by six to seven hours along the Grand Strand, said Jon Boettcher, Hurricane Coordinator for the S.C. Emergency Management Division.

"The stronger the storm, the more people will evacuate crowding the roads," he said.

During the last major evacuation, it took residents between 24 and 26 hours to evacuate, Boettcher said.

"These reversal plans may not be activated for every storm, but they do offer us flexibility," he said.

Any decision to reverse a lane in Horry County or elsewhere will be left to Sanford.

Things Sanford said he will consider before reversing lanes include:

whether it is a peak tourist period or holiday;

strength of the storm; and whether a mandatory evacuation will be ordered.

"I am guardedly optimistic about this plan," Sanford said. "Any decision, you've got to say not things that could go wrong but, 'Is it better than status quo?'"

The plan was developed after a review of evacuations during 1999's Hurricane Floyd, when highways were gridlocked with fleeing residents and tourists.

The plan adds another tool to the area's toolbox to keep residents safe when a hurricane threatens the coast, said Paul Whitten, Horry County's public safety director.

"I think it's going to be a tremendous asset to the Grand Strand," Whitten said. "I don't see lane reversals as silver bullets, but this one solves a very specific problem."

The problem could be lessened if residents consider leaving earlier during voluntary evacuations, said S.C. Highway Patrol Col. Harry Stubblefield.

"Our recommendation will be if the [Interstate 26] reversal is appropriate, then this [reversal] is appropriate," he said.

Nearly 200 highway patrol officers and 300 S.C. National Guard support members will direct traffic in coastal areas when evacuations are issued, he said.

The first evacuation with lane reversals will be a work in progress, officials said.

"I think we can make it work," Dawsey said. "I watch this traffic every day as it goes in to the beach, and then when you try to get it out in one day, it's tough."