By Brad Segall
PLYMOUTH MEETING, Pa. (CBS) -- Drivers hoping that Plymouth Road, between the Blue Route ramps and Butler Pike, would reopen sooner rather than later may not get their wish.
The bridge, which carries more than 15,000 cars a day, was shut down late last week because of a sinkhole. That shutdown has created major traffic jams in the area as drivers look for alternate routes around the closure.
Pennsylvania Department of Transportation spokesman Gene Blaum says the bridge remains closed indefinitely while they try to figure out what's causing the problems.
"We need to get a firm handle on the area underneath the bridge, because it's the foundation that seems to be significantly compromised," Blaum tells KYW Newsradio. "We have to know exactly what's taking place underneath the ground in order to determine the next course of action."
The road is built on limestone which, Blaum says, is susceptible to sinkholes because underground voids can develop.
Engineers have used ground-penetrating radar to get a better look at the situation, and will now drill into the earth to validate the radar's findings.
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