Flow control in sewer networks is an important field with regard to environmental control. Sewer flows are difficult to handle because of their specific composition and the special conditions of an underground controller arrangement in a wet and cold atmosphere. The bistable vortex throttle is a new pure-fluidic device using vortex and two-phase flow effects. The sewer flow to be controlled passes through the device and activates the flow effects. No separate control flow is needed. Characteristics were recorded in the laboratory from a full-scale device. The reliability of the new device was proved under practical conditions.