Vacuum Sewer System

Function & benefits

Vacuum Sewer System

Vacuum sewer systems are a modern, mechanized method of wastewater collection and transport, fundamentally different from conventional gravity systems. Instead of relying on ground slope, negative pressure (vacuum) is created inside the pipelines, ensuring rapid and safe wastewater flow to the vacuum pumping station.

  • Lower investment cost (60–70% compared to gravity networks).
  • Rapid installation with minimal excavation.
  • Safety in areas with high watertable, rocky or unstable soil.
  • Minimal environmental and archaeological disturbance.
  • High flow velocity (3–6 m/s) reducing the risk of blockages.
  • Built-in pre-treatment of wastewater due to air introduction.
  • Absolute tightness: no leaks or odors.
  • Only one power supply required at the pumping station.
  • Immediate fault detection via control instruments.
  • Reduced biological treatment plant requirements due to zero inflow.
  • Sewer networks in flat areas.
  • Communities with high groundwater table or unstable soil.
  • Tourist areas, campsites, marinas, and ports.
  • Archaeological sites where excavation must be minimized.
  • Mixed gravity and vacuum networks for special cases.

This technology has been successfully applied worldwide for decades and in recent years has been dynamically implemented in Greece, offering a reliable and sustainable solution for the sewerage infrastructure of the future.

 

How Vacuum Sewer Systems Work

Vacuum sewer systems are mechanized systems for wastewater transport. Unlike conventional gravity systems, they operate by creating negative air pressure (vacuum) inside pipelines to generate flow. This technology has been proven worldwide, with hundreds of installed systems. Their design in the countries of the European Union is based on the EN 16932 standard.

A typical Vacuum System consists of:

  • Vacuum Pump Station(s): where vacuum is generated and maintained, wastewater is collected via the central vacuum network, and then discharged to the nearest receptor (gravity network or biological treatment plant).
  • Vacuum Pipelines: feeding vacuum to the vacuum valves and transferring wastewater. Their sawtooth profile allows longer distances between lifts and greater overall wastewater lift.
  • Vacuum Valves & Collection Chambers: located in manholes, acting as an interface between the vacuum inside pipes and atmospheric pressure of the houses gravity sewer.
 

Vacuum valves open automatically when wastewater accumulates in the chamber, admitting both wastewater and the right amount of air, then close again. The air-to-water ratio ranges from 2:1 to 5:1.
They operate pneumatically by differential pressure, ensuring reliable and complete wastewater transport.
Specialized automation and remote-control systems ensure full supervisory control and intervention capabilities.
Intravac’s expertise in vacuum sewer networks has established it as a leader in Greece, pioneering this sector and continuing to deliver successful projects while monitoring new, improved technologies.