Sewer cleaning can happen in any season. Sanitary sewer mains are cleaned using a high performance combination jetter/vacuum vehicle (see picture at right). A cleaning nozzle is propelled from one manhole to the next using water under high pressure. The nozzle is then pulled back to the starting manhole as the water scours the inside of the sewer pipe. Any debris in the pipe is pulled back with the water. The debris is removed from the manhole with a powerful vacuum on the combination truck.
During cleaning of sanitary sewer lines, air occasionally vents into a home through the sanitary sewer service line and plumbing ventilation system. When this happens, water in the toilet bowl can bubble or surge or, in rare cases, splash out of the bowl.
Common Causes of Air Venting
Air movement from normal cleaning operations
The use of high pressure necessary when cleaning lines within a steep slope
Sewer lines running close to the building
Capped roof vent
Size and complexity of the home’s waste and ventilation system
If you happen to see a sewer cleaning machine on your street, you may want to make sure your toilet lids are down.