Things have come on a long way from the early 2000s. Back then my old man was doing the assessments around the Tararua District for all the land that had slipped and it was a case of flying around in a small plane for ages making guesstimates of how much dirt had moved :)

editing to add he was the passenger, seeing the state of some of his fence posts and fences i'm glad he wasn't the pilot in the plane given the damage he can do in a tractor.