A massive sinkhole on Interstate 5 south of Tracy disrupted traffic Tuesday and had road crews scrambling to make repairs, a Caltrans spokesman said.
The sinkhole was discovered late Tuesday morning by Caltrans workers doing routine maintenance along northbound I-5, just south of Highway 33, Caltrans spokesman Greg Lawson said.
Lawson said it could have been worse.
"We're out there; we're taking care of it," he said. "We got to it early."
Crews were tearing into the asphalt with excavators Tuesday afternoon, trying to get to the root of the problem. By evening, the hole had grown to three times its original size, officials said.
"We're not really sure (of the cause) right now, we're still investigating," Lawson said. "But there is an irrigation pipe underneath, so that's one of the things were looking at to see if that irrigation pipe had a leak or something of that nature."
The hole was about 3 feet in diameter when first spotted, and one lane of I-5 was shut down as crews began repairs. But an hour later, it was determined the damage was much more extensive, and both northbound lanes were closed around noon as Caltrans workers used heavy equipment to tear up the road and make repairs, Lawson said.
A 6-mile detour was set up along eastbound Highway 132 and northbound Highway 33. Regular drivers of the route were impacted by the delay.
"We were already gonna be pushed to make our pickup on time," said truck driver Glenn Hamby, "so this is gonna affect us quite a bit."
Lawson said if it's a pipe issue, it can be repaired fairly easily. Caltrans hoped to have the freeway reopened by Thursday afternoon, he said.