Closed ramp

Sinkhole-related damage has forced the N.C. Department of Transportation to close southbound Interstate 85’s Parham Road ramp for at least 60 days pending repairs.

HENDERSON — A sinkhole has forced the N.C. Department of Transportation to set up a detour for people who use the ramp at Parham Road to get on Interstate 85 headed south.

The hole emerged on the right side of the Exit 215 ramp and also has closed part of Wesley Drive, as it stems from the failure of a corrugated metal drainage pipe that crosses under both roads.

DOT spokesman Marty Homan said the closure will last for “at least” 60 days while engineers work on replacing the pipe, and that in the meantime the agency is detouring traffic that would ordinarily use the Parham Road ramp to another nearby at Exit 214 that branches off North Garnett Street.

The cause of the problem remains unclear, though Homan noted that corrugated pipes like the one under the ramp do rust.

“But until we really get it out, we don’t really know,” he said. “We’re seeing the symptoms and not the cause, if you will.”

Agency statistics indicate the Parham Road ramp serves less than 700 vehicles a day. The detour covers roughly a quarter-mile, and channels vehicles into a from-the-left merge onto the interstate.

Planning for the replacement involves consultations with DOT’s hydrology and geotechnical experts. Workers will probably have to “jack and bore” the new pipe, Homan said, referring to a process that involves using jacks to push it through the soil without having to dig a trench in the roadbed.

The closure began on the evening of April 9, but it’s not clear when the sinkhole first emerged. It “probably started a good bit before that,” Homan said, noting that a sinkhole “doesn’t always look like a sinkhole at first” and can resemble a less serious problem like a crumbling road shoulder.

Contact Ray Gronberg at rgronberg@hendersondispatch.com or by phone at 252-436-2850.

Contact Ray Gronberg at rgronberg@hendersondispatch.com or by phone at 252-436-2850.