Undignified and extremely common. The overflowing toilet is read as what should have been released, refusing to leave — in the East waste and wealth strangely paired, in the West emotional processing backed up, in Ibn Sirin's tradition private matters spilling past their bounds.
Three readings
In Chinese tradition · 周公解梦
The Chinese classics are famously cheerful about filth: excrement in dreams is wealth — 粪 as fortune — and an overflow can read, startlingly, toward money arriving in excess of the vessel. But the tradition also reads blockage honestly: what should flow away is backing up. The double reading asks a sharp question: is this abundance overwhelming its container, or waste you have failed to release?
The plumbing of a dream house is the psyche's processing: the toilet is where the finished and the toxic get released. An overflow is processing backed up — emotions, obligations, or others' problems taken in faster than you can discharge them. Dreamers in caretaking roles and boundary-poor jobs get this dream constantly. Its bluntness is its kindness: something must be allowed to leave, and the pipe is yours.
Read in the tradition's spirit, the privy is where one is rid of what burdens; its overflow marks private matters — burdens, expenditures, or troubles — exceeding their proper place and threatening to be seen. Cleansing after reads toward relief and purification. As meaning: something you should have let go of is spilling past its bounds — the dream asks for release, and for the boundaries that make release possible.
Toilet dreams track processing and privacy — two things modern life strains constantly. Overflow versions cluster in caretakers and the boundary-poor: people taking in more than they can discharge.
Is the Chinese wealth reading serious?
Entirely — 周公解梦 reads excrement toward fortune, and dreamers of the tradition greet these dreams cheerfully. The overflow variant holds both readings at once: abundance, and a container too small for it.
What does cleaning up the overflow mean?
The cleanup reads as the work of release actually done — boundaries repaired, the backlog processed. It is the resolution the dream wants; dreamers often report the dream stops recurring after it.
This is the general reading. Your dream is specific.