City of Davis 66-Inch Influent Sewer Slip-lining

This project involved the rehabilitation of the sewer trunk main into the City’s wastewater treatment plant. A 900’ section of 42” HDPE pipe was sliplined inside the existing 66” RCP trunk main up to the City’s treatment plant headworks. Bypassing the flows to the treatment plant proved to be problematic as the 66” influent line ran under an existing canal, as well as neighboring wetlands and Fish and Game requirements. The crews were able to design and construct a temporary bypass to control flows to allow for installation of the liner pipe. M&H resolved numerous design issues to facilitate construction including adjusting the location of the insertion pit. These changes helped both the City of Davis and McGuire and Hester expedite the project.

Deep excavation of 30’ plus was performed at the insertion and receiving pits. The initial project design utilized pipe bursting methods, but due to conditions encountered in the field shoring options were modified, methods were changed, and the project switched to strictly sliplining to improve the existing facilities. Additionally, 6 manholes were modified/ upgraded at various other locations along the trunk main utilizing Armorock polymer manhole insert material. At the completion of the slipline work, a 0.75 mile section of access road was restored via lime treating with an AB cap. The project was performed under tight schedule constraints to complete the work and restoration prior to the wet season.