TRACY, Calif. (KFSN) --A section of Interstate Five near Tracy remains closed as Caltrans tries to figure out why a massive sinkhole opened up Tuesday.
The hole gradually spread across two lanes of traffic after workers first spotted it. Traffic has since been diverted to Highways 33 and 132 during repairs.
Workers have dug nearly 35 feet to determine a cause but have come up empty so far.
An irrigation pipe was located directly beneath the sinkhole and it's unclear if it's connected to collapse.
Caltrans is planning to have the road opened by Thursday afternoon.