>saw very large main at a horse farm that left a crater big enough to hide a school bus in the ~30 seconds it took to shut down.

I used to build houses. Heard an excavator hit a water main in a cul-de-sac. Not sure the size but it made a very big hole very quickly. Took a few minutes to find someone with the proper tool to shut water off for the entire street. Good thing it was at the top of a hill. =)