Water leaks are common, especially this time of year. But, a hole, 8-feet in diameter, in the middle of a busy intersection, is far from typical.
"I've heard about it happening in Chicago because that's where I'm from, but I've never heard of this happening in Madison before," says Allison Nowak.
The UW student encountered an unexpected detour on her walk to class.
"This is unique," she says.
The "this" she is referring to is the result of a water main break at the corner of State and Lake Streets.
"The cold weather causes the frost to push the earth down and it cracks the pipes," says Bob Kempfer with Madison Water Utility.
The original hole was about half the size, about 4-feet in diameter. Kempfer says it got its start from heavy force above.
"7 o'clockish (Tuesday morning) a bus came through and the concrete gave way. They got the bus out and we got called and came out," says Kempfer.
That was news to Madison Metro. A spokeswoman says there are no reports of such an incident happening.
According to the 911 Communications Center, the hole was called in by a police officer.
Regardless of what happened, onlookers can't get enough of this rare site.
"It would be very scary to fall through the street. It's not something you expect to happen," says Nowak.
Kempfer says the city has responded to nearly 120-water leaks this month alone. But, none quite like this.
"It could have been going on for a few days. It just wasn't surfacing, so we wouldn't know about it," he adds.
Crews were on the scene for about eight hours. They had to extremely careful because there is a gas line next the water main.
State and Lake Streets are back open. Permanent repairs will be made in the spring when the temperatures warm up.
Tuesday's work was done without shutting off water to nearby businesses.