AIRVAC Vacuum Sewer System

Valve Pit l Vacuum Mains l Vacuum Station

Vacuum sewers use small diameter PVC pipe installed in shallow trenches. Vacuum mains are slightly sloped towards the vacuum station. In flat terrain with no unusual subsurface obstacles present, a vacuum main can typically be extended to a length of 10,000 feet from the vacuum station. Click here for more information regarding line sizes, slopes and line lengths.

Profile changes, called lifts, are used to minimize trench depth. The line profile is designed to ensure that sewage will not block the pipe at low flow periods when the sewage is at rest.



"We liked AIRVAC because it did not require large pipes nor deep burial depths." - Paul Moore

"With vacuum you can “field engineer” in some cases. You can actually redirect the line for a few feet to get around an obstacle such as a tree or buried utility you didn’t know was there. You can’t do that with a gravity sewer.” -Chuck Brunkart

Click Here to find out what more of our customers are saying about AIRVAC!

Trench depth

AIRVAC’s patented saw-tooth profile keeps sewer lines shallow. Vacuum mains are typically installed within 1-2 ft of the minimum trench depth required by code.

Line length

There is a potential vacuum loss associated with every lift in the saw tooth profile. This limits the length of each vacuum main to about 10,000 ft (3 km) in flat terrain. Elevation changes along the route can extend or reduce this range.


Vacuum mains are slightly sloped (0.20%) towards the vacuum station. Unlike gravity sewers that require a minimum slope for a given pipe diameter to obtain the 2 ft/sec scouring velocity , vacuum sewers have no such requirement as the velocity in a vacuum main is independent of both slope and pipe diameter. The pressure differential results in velocities of 15 to 18 ft/sec.

Line sizes

Line sizes are typically 4”, 6”, 8” and 10“ (100 to 250 mm) SDR 21 gasketed PVC pipe. PE pipe can also be used.