Thorny Details of the Rose Canyon Trunk Sewer Rehabilitation

The Rose Canyon Trunk Sewer (RCTS) is a 60-inch diameter plastic-lined reinforced concrete pipe (PLRCP) with plastic weld strips installed at each joint. Following inspections, it was observed that the lining at the joints had failed. The RCTS runs throughout an open space, environmentally sensitive area rich with riparian habitat. Other alignment challenges included multiple railroad crossings and an adjacent freeway. Numerous trenchless rehabilitation options were evaluated to repair the failed plastic liner weld strips, including both joint repair and lining methods. The potential environmental, encroachment, and community impacts of the rehabilitation along with the overall cost and construction schedule were considered in the ultimate recommendation. Internal mechanical pipe seals were selected to repair the pipe joints via manned entry of the trunk sewer, as this method was the least invasive to the environment and the most cost effective. Details of the development of the RCTS rehabilitation design along with the lessons learned during the construction will be discussed.