Plumbing runs unseen inside the walls, so dream books read it as the hidden flow of emotions. Faulty pipes stand for feelings blocked or leaking where they should not.
When this appeared in your dream, what were you feeling?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.