Timeline: A look at what’s happened
Gravity Tunnel Project Construction Completion
With the connection of the final FRP segments in the gravity tunnel at the Airport Access Shaft location, construction of the gravity pipeline was essentially complete. Final steps involved demobilization and restoration of the Airport Access Shaft site. Final completion of the GP project involves coordinated startup, which is anticipated to occur in mid-2023 once the other wastewater conveyance elements of the RESCU Program are online.
Completion of Pipe Installation inside Gravity Tunnel (GP Project)
Installation of Fiber Reinforced Polymer (FRP) pipe was completed over the full 3.5-mile length of the new gravity tunnel. FRP pipe installation involved maneuvering 20,000lb pipe segments into position with custom pipe transport equipment to account for segment length and tunnel curvature.
Planning for Systemwide Startup
Planning for RESCU Program system-wide startup moved to including the entire team in February 2022. Planning effort involved coordination between SVCW management and O&M, design-builders, and the construction management team.
Pipe Installation at Tunnel Drive 2 (Gravity Pipeline project)
Tunnel Drive 2 was completed at the of end June 2021. Salus was removed from the shaft, and installation of Fiber Reinforced Polymer (FRP) pipe for Tunnel Drive 2 begins.
Start of Micro-tunneling Activity (Pump Stations Improvements project)
Micro-tunneling on the Pump Stations Improvements project begins. The tunneling work uses a Micro-Tunnel Boring Machine (MTBM) to construct the Belmont Gravity Pipeline, that will convey wastewater flows from the City of Belmont to the drop structure connection to the new gravity tunnel adjacent to the existing San Carlos Pump Station. This construction work is expected to take 22 months.
Completion of Tunnel Drive 2 (Gravity Pipeline project)
Tunnel Drive 2 is completed at the of end June 2021, when Salus, the Tunnel Boring Machine (TBM), broke into the receiving shaft at the Front of Plant. Salus was removed from the shaft, cleaned, and hauled offsite for use in other tunneling projects not associated with SVCW’s project. This is the Gravity Pipeline project’s second major milestone.
Major Mechanical and Electrical Equipment Installed (Front of Plant project)
Major mechanical and electrical equipment have been installed at the Front of Plant project site. This includes electrical equipment installed in the Headworks electrical room and major equipment, such as the Odor control system biofilters and granular activated carbon vessels. Other equipment that was installed includes the grit washer classifier, Headcell grit removal unit, and odor control piping and fan units.
Mobilization to Menlo Park Pump Station and San Carlos Pump Station (Pump Stations Improvements project)
Mobilization to Menlo Park Pump Station and San Carlos Pump Station sites for site preparation begins. This includes setting up of fences, trailers, and staging areas for construction.
Installation of Interconnection Pipeline (Front of Plant project)
Installation of the Interconnection Pipeline (IPL) begins. The IPL is the 63-inch in diameter pipeline that conveys wastewater by gravity from the new Headworks Facility to the existing Wastewater treatment plant influent structure.
Pipe installation at Tunnel Drive 1 (Gravity Pipeline project)
Tunnel Drive 1 was completed at the of end March 2021. Salus was removed from the shaft, and Fiber Reinforced Polymer (FRP) pipe sections were being transported from the pipe storage yard in Sunol to the project site in Redwood City for installation in the tunnel. Installation of the FRP pipe sections for Tunnel Drive 1 begins.
Mobilization to Redwood City Pump Station (Pump Stations Improvements project)
Mobilization to Redwood City Pump Station for site preparation begins. This includes setting up of fences, trailers, and staging areas for construction.
Completion of Tunnel Drive 1 (Gravity Pipeline project)
Tunnel Drive 1 is completed on end March 2020, when Salus, the Tunnel Boring Machine (TBM), broke into the receiving shaft at Inner Bair Island. Salus was removed from the shaft, inspected, and retooled for the Tunnel Drive 2. This is the Gravity Pipeline project’s first major milestone.
Start of Tunneling Activity (Gravity Pipeline project)
Tunneling on the Gravity Pipeline project begins. There are 2 tunnel drives on this project, with Tunnel Drive 1 heading from the launch shaft at the intersection of Shoreway Road and Holly Street, to a receiving shaft on Inner Bair Island and Tunnel Drive 2 heading from the same launch shaft to a receiving shaft at the Front of the Plant project site adjacent to the SVCW WWTP.
Start of Excavation of Surge and Flow Splitter (SFS) Shaft and Receiving Lift Station (RLS) Shaft (Front of Plant project)
Excavation work on the SFS and RLS shafts begins. The SFS shaft is a vertical shaft located immediately to the west of (and upstream of) the Receiving Lift Station (RLS) shaft; the SFS shaft which will provide flow protection during wet weather events by acting as a surge tower. Wastewater will flow from the SFS shaft into the RLS shaft through two 60-inch diameter manifold pipes. The wastewater will be pumped out of the RLS through discharge pipes dedicated to each RLS pump and into the Headworks facility for preliminary treatment. The SFS shaft will be excavated to a depth of about 70 feet, while the RLS shaft will be excavated to a depth of about 90 feet.
Pile Driving Work for Headworks Facility
Construction of the Headworks facility begins. Piles are driven into the soil to provide structural support for the construction of the Headworks facility. The Headworks Facility plays a crucial role in the pretreatment of the influent wastewater. It involves screening of inorganic fibrous materials, such as rags, wipes etc. and the removal of inorganic grit material, such as sand and silt, all of which can interfere or damage the treatment processes in the Wastewater Treatment Plant.
Shaft Work Begins
The Gravity Pipeline project tunnel launch shaft sitework begins northeast of the intersection of Shoreway Road and Redwood Shores Parkway/Holly Street intersection. Major construction for shafts also began in late September for the FoP project and is expected to take 12 months.
In July we broke ground for the Front of the Plant (FoP) facilities and gravity pipeline tunnel, culminating four years of planning and design to rehabilitate the agency’s aging infrastructure and facilities.
Nov 9, 2017
Approved Agreement with JF Shea-Parsons Joint Venture team
On November 9, 2017 the SVCW Commission approved a Design-Build agreement with JF Shea-Parsons Joint Venture team. (FoP)
Oct 11, 2017
Approved Agreement with Bernard-Bessac Joint Venture team
On October 11, 2017 the SVCW Commission approved a Design-Build agreement with the Bernard-Bessac Joint Venture team that includes Arup as the design engineer. (GP)
July 31, 2017
Heavy Construction Begins
The FoP project heavy construction will begin on Monday July 31 and last about three weeks. Additional bulldozers, earth movers, dump trucks, lime spreaders and mixers will arrive Monday morning and then the actual work will begin Monday afternoon or Tuesday morning (August 1).
April 13, 2017
Approval of RESCU Program
The Silicon Valley Clean Water (SVCW) Commission on Thursday, April 13, approved the Regional Environmental Sewer Conveyance Upgrade (RESCU) Program, which consists of replacing or rehabilitating nearly all components of the existing conveyance system, including pipelines and pump stations.
Design- Build Procurement Process Approval
The Commission provided direction to proceed with this procurement method. PDB
Design- Build Procurement Process Recommendation
SVCW staff made a recommendation to the Commission in December 2016 to use a Design- Build procurement process for implementing the conveyance system design and construction.
Environmental Impact Report Preparation
SVCW is currently preparing an Environmental Impact Report for its Conveyance System Program and we anticipate the draft report will be available for public review in mid-to-late November. When it is available, we will post a notice on our website to inform anyone interested in how to access the report.
Capital Improvement Program Initiated
SVCW in 2008 initiated its Capital Improvement Program (CIP) to replace and rehabilitate the wastewater conveyance and treatment systems in a structured and prioritized manner.
Identification of Needs
Engineering studies determined that the majority of SVCW’s fixed assets were beyond their useful lives and needed replacement. The pipelines were experiencing more frequent leaks and the facilities, including pump stations, were deteriorating.