Many sewer rising mains have several things in common: They are a critical asset to the asset owner, as it is often complicated to divert the flow for an extended period of time. The accessibility to the pipe is mostly difficult, as the mains run through densely populated or environmentally sensitive areas or under creeks and main roads. The pipelines often have several bends in the run of the main. Faulty sewer rising mains have the potential to cause pollution, damage property and neighbouring services, resulting in significant costs.
Failures on rising mains can be caused by external corrosion, internal corrosion or mechanical failures like leaking joints, longitudinal cracks, etc. In many cases the pipeline is still able to withstand the traffic loads, but not the internal pressure loads. A renovation using swagelining or slipining with HDPE is often not acceptable due to the significant diameter reduction, the limitation of installing through bends, the pit sizes and the duration of the installation.
