ATLANTA (AP) Highway engineers have discovered almost 100 mi. (161 km) of crumbling foundations under interstate highways in Georgia, with a repair price tag of at least $193 million.
Motorists will pay another price in transportation delays when contractors begin digging up and replacing sections of I-285, I-75, I-85 and I-185.
The state Department of Transportation disclosed last week repairs were needed to the deep foundation of a stretch of I-75 south of Atlanta, from I-675 south to GA 16 in Butts County.
DOT engineers discovered the problem as work was winding down on a two-year, $10.2 million project to repave the 24-mi. (38.6 km) stretch of highway.
Officials say the DOT has found crumbling foundations under several more stretches of highway totaling nearly 70 mi. (112.6 km). Some of the sections have reached their useful life, said Buddy Gratton, the state maintenance engineer for the DOT.
The longest segment, nearly 34 mi. (54.7 km) long, stretches along I-185 through Muscogee, Harris and Troup counties. Four other major sections are all in metro Atlanta.
Foundation problems can lead to ruts, premature wearing and cracks.
”We’re seeing distresses,’ Gratton said of the freeway sections identified. ”You’ll get slow moving water across the roadway and that’s your major safety concern because of the potential for wet weather accidents.’
The state budget currently has no funds identified to repave the five immediate projects. The DOT will request money during the next three years, which will leave less cash for other road projects.
The problem could grow. The stretches of highway already pinpointed are among 50 that have been identified for testing to see if asphalt beneath the road surface is crumbling, Gratton said.
The roads being tested were constructed with an asphalt mix similar to that used to build the section of I-75 south of Atlanta that is now crumbling. It was a common mix used to build asphalt roadways across the country at that time.
The foundation problems are caused by water seeping into the roadbed. In the early 1980s, engineers began using an improved mix, which does a better job keeping out water.
The same problem was discovered two years ago on the southeastern leg of I-285. The repairs forced extensive closings and traffic delays.
Since 2000, the DOT has dug up and replaced nearly 30 mi. (48 km) of I-75, I-85 and I-285 to fix crumbling road beds with the same asphalt mix