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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Gravity Pipeline Project

Last Updated May 2021

TBM Status Update – May 17, 2021

As of Monday, May 17, 2021, Salus tunneled 11,098 feet from the launch shaft and built 2,214 rings. Salus remains on target for break-in to the surge-flow splitter (SFS) shaft.

The jet grout columns and permeability test production columns were recently completed. Quality control work on the jet grout columns adjacent to the SFS shaft continue, assuring that the columns meet the required strength and permeability tests. These activities will ensure a safe break-in when the TBM enters the shaft.

BBJV and Shea Parsons Joint Venture continue coordination efforts to prepare for the safe arrival of the TBM.

Monthly Update: April 2021

Salus, the Tunnel Boring Machine (TBM), just entered its last stretch of tunneling while SVCW’s contractor partner, Barnard-Bessac Joint Venture (BBJV), prepares for its breakthrough at the Surge-Flow Splitter (SFS) shaft at the Front of Plant project site.  
The SFS shaft will receive the TBM at the end of her drive and will then be re-used for wastewater flow management once the Receiving Lift Station (RLS) and tunnel are complete. To prepare for Salus’s breakthrough, BBJV is installing jet grout columns – to prevent groundwater entering – and demolishing part of the receiving shaft’s wall at the point where Salus will pass through to the receiving shaft.
At the San Carlos Pump Station site, special excavation equipment was used to remove soil from the interior of the recently completed San Carlos Shaft. Air ventilation ducts were installed to provide a well-ventilated space for the workers to perform any work within the shaft.

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Gravity Pipeline Project

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