According to the laws of science, every occurrence can be explained scientifically. This is also supposed to apply to plumbing experiences. But sometimes the weird things that happen in a plumbing system are hard to explain.

I have accumulated a list of some of my weirder experiences with plumbing systems. Some may be obvious to you, others may not. These weird experiences would make for good questions to put to fourth– or fifth–year apprentices. Sometimes, it takes more thought to figure out what went wrong.