Started digging last Sunday morning with an Electric jack hammer and a lot of anxiety about where the pipe ran mystery, but all in all felt pretty good about my best guesstimating. Took out a 12"² piece of the previously unknown 4" concrete pad under my asphalt and burried under it, dead center, was a 4" clay pipe that ran verticaly down to the main.
The place where the dousing indicated water appears to have no pipe but most likely is the path of the run off from the break... btw.