Wall collapses onto unfinished toll lanes in Cobb County

A retaining wall collapsed onto an unfinished portion of toll lanes that sit along I-75 and Windy Hill Road in Cobb County.

Drivers in Cobb and Cherokee counties are eagerly awaiting the opening of new toll lanes along I-75 and I-575 this summer, but the Northwest Corridor Express Lanes project may have hit a snag.

Between Friday night and Saturday morning, a retaining wall collapsed onto an unfinished portion of the toll lanes that sit along I-75 and Windy Hill Road in Cobb County, according to the Georgia Department of Transportation.

A retaining wall collapsed onto an unfinished portion of toll lanes that sit along I-75 and Windy Hill Road in Cobb County. JOHN SPINK / JSPINK@AJC.COM

Credit: JOHN SPINK / JSPINK@AJC.COM

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Credit: JOHN SPINK / JSPINK@AJC.COM

It is not clear what caused the wall to collapse or how it might affect the timeline of the project.

“We are going to have the design team and engineers ... on site doing a complete investigation to determine cause,” GDOT spokeswoman Natalie Dale told The Atlanta Journal-Constitution in an emailed statement.

Because “this is still an active construction zone,” no vehicles were on the highway and there was no impact to traffic during the morning commute.

The Northwest Corridor Express Lanes, once finished at the end of the summer, will stretch 30 miles on I-75 and I-575. State transportation officials say the limited access "express lanes" will whisk drivers from Acworth or Canton to the Perimeter in minutes, even if traffic in the regular lanes is at a standstill.

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MORE: New metro Atlanta express lanes: Traffic relief if you pay by the mile

The project is part of a planned 120-mile system of metro Atlanta toll lanes that state transportation officials say will make commuting easier and more predictable for those willing to pay by the mile. That system already exists on parts of I-85 in Gwinnett County and I-75 in Clayton and Henry counties.