An example system includes a sewage pit; a suction pipe extending into the sewage pit; and a valve between the sewage pit and a vacuum pipe having a vacuum pressure. The valve is controllable to close or to open to allow content to flow from the sewage pit, through the suction pipe, to the vacuum pipe. A sensor tube extends into the sewage pit to sense a fill level of the sewage pit. The suction pipe is configured as a back-up to the sensor tube for sensing the fill level of the sewage pit. The valve is controllable based on a pressure in at least one of the suction pipe or the sensor tube meeting or exceeding a predefined level.