Flovac Vacuum Pump Station

The vacuum station essentially sucks the sewage and air to a central point and then pumps the sewage to its intended location. The vacuum station has duty and standby vacuum pumps that create a vacuum in the vacuum sewer lines and an enclosed collection tank. When the vacuum mains deliver sewage and air to the pump station, Sewage pumps transfer the sewage from the collection tank through a rising main to the treatment plant or gravity network. Available packaged vacuum stations consisting of two or more vacuum pumps, two sewage pumps, a collection tank and controls. Packaged vacuum pump stations arrive at the job site pre-piped, pre-wired and factory tested to minimise construction cost.

Vacuum pumps typically run 2 to 3 hours each per day depending on the design approach and don't need to run continuously since the vacuum interface valves are normally closed. As sewage enters the system, driven by air at atmospheric pressure, the system vacuum will slowly decrease from -70kPa to -50kPa. The vacuum pumps are sized to increase the system vacuum from -50kPa to -70kPa in three minutes or so. The two non-clog sewage pumps are each sized for peak flow. Energy consumption can be calculated at the design phase for a particular project.


The collection tank is usually mild steel or stainless steel and is sized according to flow with typical sizes ranging from 3.8 to 15 cubic meters. The incoming vacuum lines connect individually to the collection tank, effectively dividing the system into zones.


Monitoring at the pump station can alert operators to a number of things.

  • Long pump hours or a low vacuum alarm suggesting a blockage in a vacuum valve in the reticulation or a break in the vacuum main.
  • High alarms for the tank to notify of problems with the discharge pumps
  • Pump faults calling for service to vacuum or sewage pumps
  • Information for asset owners about pump efficiencies as well as air/liquid ratios to assist with power saving
  • The pump station building can vary considerably depending on the type of project. It can be designed to fit in with other houses in the areas or if in an industrial area could be placed inside a container. In some projects the pump station has been put completely underground.