Gravity Pipeline Tunnel
Client
Silicon Valley Clean Water (SVCW)
Location
Redwood City, CA
The Gravity Pipeline (GP) Tunnel project consists of the design, construction, permitting, connections to the existing conveyance system at two locations, start-up, commissioning, and closeout of an approximately 3.5 mile, 16-foot diameter concrete-segment lined tunnel using a Herrenknecht Earth Pressure Balance (EPB) shield tunnel boring machine (TBM) and a two-pass tunnel lining.
The tunnel route passes beneath environmentally sensitive areas of the San Francisco Bay, a County airport, roadways, residences and commercial businesses. The work also includes three, deep shafts, ranging in depth from 40 feet deep to 55 feet deep, to connect to the existing conveyance pipelines and pump stations. It interfaces directly with the two other RESCU projects.
To date the Gravity Pipeline Tunnel project has received 10 awards for outstanding achievement in 2023 from AEC industry organizations including APWA, CMAA, DBIA and ENR.
January 17, 2020
Gravity Pipeline Project Progress (0:00-1:17)
Views of the Tunnel Boring Machine (TBM) launching shaft, the elevator that transports workers to and from the tunneling construction site, and the concrete segments that line the gravity tunnel and include water lines, electrical conduits, ventilation ducts, and tracks for the TBM’s trailing gear (also known as “gantries”). Construction of the Inner Bair Island receiving shaft continues.
