What is the Gravity Pipeline Project?

The Gravity Pipeline (GP) Project consists of the design, construction, permitting, start-up, commissioning, and closeout of approximately 17,600 feet of wastewater gravity FRP pipe inside a concrete-segment tunnel. The work includs three shafts and will interface directly with the Front of Plant (FoP) Project at the Receiving Lift Station (RLS). Work is being implemented under a Progressive Design-Build procurement process.

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What's Happening

Gravity Pipeline Project

Last Updated July 2020

TBM Status Update – July 27, 2020

Since its launch at the end of June, Salus, the Tunnel Boring Machine (TBM), has advanced 240 feet from the launch shaft and 48 rings were built. Salus is currently stopped from forward movement to install more gantries, or support platforms, in the tunnel behind the TBM.

Barnard-Bessac Joint Venture and SVCW’s technical team will continue to closely monitor Salus’ operations inside the tunnel, and meet as a Tunnel Task Force team to review its performance and discuss any potential issues.

July Monthly Update

Salus, the Tunnel Boring Machine (TBM), safely began her second drive from the launch shaft to SVCW’s wastewater treatment facility late June. Barnard-Bessac Joint Venture (BBJV), the contractor partner for the Gravity Pipeline project, connected all of Salus’ electrical components. These components included gantries, a frame structure raised on side supports, that house the equipment needed to power and run the TBM throughout its drive. Gantries also serve as an entryway to deliver concrete support rings to the front of Salus for installation.

BBJV transported the final segments of fiberglass reinforced polymer (FRP) pipes from the Port of Stockton to the storage yard in Sunol. They are wrapped in a protective blue tarp and stored in the yard until ready for installation in the new tunnel created by Salus.

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Gravity Pipeline Project

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