Pictures from Chopper 11 showed the truck under the bridges for the Interstate 295 interchange.
Authorities said the accident happened around 8:30 a.m. Traffic in the southbound lanes quickly backed up for miles.
Workers were seen loading dead pigs into a dump truck. It wasn't immediately clear how many animals were killed.
Authorities say no humans were hurt in the crash.
A large wrecker truck was used to right the hog truck, but but it took hours before southbound I-95 could be reopened.