PVC Sewer Pipes: Proven, Reliable and Cost-efficient

PVC Sewer Pipes: Proven, Reliable and Cost-efficient - Vinyl Council Australia

February 15 2012

PVC pipes have traditionally been used for sewer systems as the material of choice for the past 37 years in Australia so there is a good track record from which to gauge performance. Sewers need to be fully sealed systems to overcome infiltration, exfiltration and tree root intrusion. The results of any of these issues can be very unpleasant for surrounding communities, and costly for the water authorities. Therefore the pipe system joint method and reliability is crucial to ensure a well performing sewer system.

Peter Klouda, Technical Support Engineer for Iplex Pipelines Australia gave a presentation in Canberra recently to Institute of Public Works Engineering Australia comparing sewer pipe performance. He was responding to a question as to whether a polyethylene (PE) sewer system which combines welded pipe and fabricated fittings would be an improvement on the existing PVC rubber ring jointed systems. Some concerns have been raised by authorities and councils about the risk of infiltration due to the rubber ring system.

Klouda therefore wanted to explore whether there would be significant benefits in switching to a PE system with its different joint system. The PE system has seen some limited use in Australia over the past five years, however, nowhere else in the world is PE being used for sewer systems.
Klouda found a number of differences between the two systems, notably:

• A potential loss in flow of as much as 12 percent with PE pipes as they have a smaller internal diameter.
• That 60 to 80 percent of infiltration when it occurs has nothing to do with the pipe system itself, and more to do with Overflow Relief Gullies and illegal connections to the sewer.
• That the PE pipe system was 80 percent more costly to install than the PVC system, partly because of the cost of the PE joints. If house connection costs were added on to this, the PE system could end up 120 percent more expensive.

Kouda concluded that it is critical when choosing the right product for the system that its service life and the overall costs are determined, including the cost of the pipe, its installation costs, maintenance and repair costs, depreciation and the total asset cost. His investigation found that PVC sewer pipes have a known history, lower installation cost and lower repair cost. Why change?