We have a brook running under our house in a culvert. At this time of the year the water is just a trickle. Occasionally we do some maintenance like repointing and underpinning on the walls and this morning a property maintenance builder bloke showed up to do some work. He had just got set up with his planks and wheelbarrow when there was a roar and a 2 foot high torrent of muddy water came down, washing everything away. Luckily he was able to jump out, I reckon that if he had been knocked over he could have banged his head on a rock and died. He found his barrow and some of the planks later, a hundred yards downstream.
I rang United Utilities in fury and after insisting, got to speak with somebody senior who rang me back later and admitted that today is one of two days in the year when they open the scour valve in the reservoir upstream to test it. He told me they checked immediately downstream of the dam but obviously couldn't be expected to check the several miles down to the river.
So what would the coroner have said? Our fault? The builder's fault? Death by misadventure? In the ten years we have lived here we've never seen this happen.