Every time I give one of my Science of the Surf community talks I always get asked the same question “Do sand bars collapse?” and I always give the same answer “No, sand bars do not collapse unless you blow them up with explosives”.

Sand bars are big piles of sand that are pretty solid and heavy. Sure, they shift around from time to time, but this takes days, weeks and even months. They never, ever, ever implode on themselves. It just doesn’t happen.

But you still hear stories of collapsing sand bars getting people into all sorts of strife. So where did this myth come from? Well, if it’s wacky and related to the beach, it must come from… Bondi.