Upon further inspection it looks like it is about 2 to 2.5 feet deep, extending into a little cave, maybe 6 feet long heading toward the pond. The roof of the cave is pretty much the two inches of asphalt. Yesterday, the hole might have swallowed Turkey Trotters on their way to the run.
I called Dispatch and asked for the Street Department to block off the road and then stopped in to let Station 9 know what the dealio was. When those guys got there to cone it off, the Street Department already had it blocked off.
No sign of buried treasure or even any dinosaur eggs in the cave. Still pretty cool to see. Usually I only see cavitation like this around broken water mains. There you go.
Update. Looks like the street will be shut down for a while: