According to news reports, and a visit with a resident near the break, the water started flowing about 0600. It did undermine the pavement, creating the hole full of water you can see on the news video, as well as a lot of other damage.
The culprit was a 12 inch main breaking. The resident I visited with said he called the city about a week ago to report water on the street. The problem is there is frequently water on Holmes Road, although I would have to say not usually this far south--but I bet no one in the water department got very excited about the report.
It's not just the main that will need repair--the buckled street will also need fixing. Holmes Road will not be normal for several days.
Just what we needed with many people using it as an alternative with the Triangle problem.
Cell phone pics of the crews at work this muggy day. From the top: view of the work area looking south, some of the damage to the pavement, hoisting out the broken main, and preparing the new main. You can tell how deep that hole is from the ladder in it. It is deep enough that you can only see a man's head if he's standing in it, plus it required shoring.