Portion of a fluid drainage conduit for a turbomachine

A portion of a fluid drainage conduit for an aircraft turbomachine, comprising an upstream stretch, a downstream stretch fixed relative to the upstream stretch and a retention chamber onto which the upstream stretch opens, the retention chamber being capable of communicating with the downstream stretch through at least one first aperture and at least one second aperture provided so as to be arranged lower than the first aperture during operation of the turbomachine, the retention chamber being arranged so that the fluid coming from the upstream stretch flows by gravitational flow towards the retention chamber, the drainage conduit portion further comprising an obturator configured to obturate the second aperture, the first and second apertures being provided so that when the obturator obturates the second aperture, the retention chamber is capable of retaining fluid while allowing a fluid overflow to flow from the upstream stretch to the downstream stretch through the first aperture, and when the obturator does not obturate the second aperture, the fluid can flow from the upstream stretch to the downstream stretch at least through the second aperture.