A stretch of southbound U.S. 61 South has sloughed again, and two-way traffic on the highway’s northbound lanes is planned while repairs are attempted.

The subterranean slide area near Signal Hill Drive is about 500 yards long has caused intermittent problems since the highway was built decades ago.

Today, there’s a major dip in the southbound lanes. Lighted signs warn motorists about the slide area.

During work by the Mississippi Department of Transportation, repairs will require both lanes to be temporarily closed, district engineer Walter Lyons said.

The MDOT closed the left southbound lane after new buckling was reported to E-911 about 7:45 a.m. Monday, said the MDOT maintenance supervisor for the Vicksburg area, Lamar Davis.

Though the right south-bound lane remains open, plans are for it to be closed as soon as crossover pavement and signs to create temporary two-way traffic in the northbound lanes are in place, Lyons said. Crossovers of the median on either side of the slide area will be improved to allow the switch, he added.

“We’re going to lose the southbound lanes,” Lyons said, adding that the MDOT will do everything it can to prevent slide damage to the northbound lanes as well.

Signs have been ordered and two-way traffic in the northbound lanes could be in place as early as next week, Lyons said.

Meanwhile, geologic consultants to the MDOT will continue to monitor and assess the slide area for the next couple of months as major reconstruction of the southbound lanes is planned, Lyons said.

If the slide area of the southbound lanes stabilizes quickly then those lanes may be temporarily fixed and the highway’s normal traffic pattern restored until work on the major reconstruction begins, Lyons said.

“The big fix could take a year,” Lyons said.

About six workers from the local MDOT maintenance crew were working to re-level the pavement in the left southbound lane Monday morning.

A meeting of MDOT management and engineers was held later in the afternoon where progress of a geologic survey that was begun last summer on the slide area was discussed.

Work on the same area of the southbound lanes had been necessary about two weeks ago.

“The same area just keeps moving,” Lyons said. “We just keep piling asphalt on top of it.”

Two separate, smaller slides to the south of the area were repaired during the early to mid-1970s, said MDOT geotechnical engineer Sean Ferguson.

“The other two have held but that one never really held,” Ferguson said of the current problem area, which he said has been sliding longer than the lanes of U.S. 61 above it have existed. “It’s been creeping for 30 years.”

Lyons said he attributed the recent movement in the slide to the unusually large amount of rainfall the area received in 2004 and through the winter months of this year.

“Water’s what makes the slides move,” Lyons explained. “When you have a dry spell, cracks open up.”

Lyons said the problem is a priority for the district and that a paving crew of about 25 workers would be working in the area today. He said he hoped motorists would drive slowly around the workers and be patient as the MDOT works to fix the problem.

“It’s a big problem,” he said. “It’s going to take us a long time to fix it.”