Monday, March 2, 2015

The New Irvington Tunnel is officially in service!

Our teams are excited to announce that the New Irvington Tunnel is officially in service carrying drinking water to our 2.6 million Bay Area customers.

This is a major milestone since the completion of the New Irvington Tunnel Project completes the last three tunnels in the Water System Improvement Program (WSIP), creating a critical water lifeline able to withstand earthquakes on the Hayward, Calaveras, and San Andreas faults.

Located between the Sunol Valley and Fremont, the new seismically-designed tunnel is the last of three tunnels making up this “water lifeline” around the Bay.  The project is part of the agency’s $4.8 billion Water System Improvement Program.

The tunnel was constructed by the joint venture of Southland Tutor Perini who began tunneling in March 2011. It was constructed using conventional mining techniques from four separate headings using road headers and controlled detonation to break up the hard rock.
Tunnel Facts:
  • Tunnel Length: 18,660 feet or 3.5 miles
  • Location: Parallel to the existing tunnel between Sunol Valley and the City of Fremont 
  • Depth: Between 30 feet and 700 feet underground
  • Finished internal diameter: 8.5 feet
  • More than 7.8 million pounds injected into the tunnel
  • The New Irvington Tunnel will carry approximately 120 million gallons of water a day on average during normal operating conditions when both tunnels are in service.
  • The maximum amount of water the tunnel can transport per day: approximately 300 million gallons 
  • This project provided approximately 42% of total labor hours to SFPUC service territory residents, and nearly half (48%) of total apprentice hours to SFPUC service territory apprentices ensuring our local workers and local residents were able to participate in this unique, once-in-a-lifetime construction opportunity.
What Happens Next?

Now that the tunnel is in service, the construction team will begin restoration of the above ground facilities. The SFPUC will take the existing tunnel out of service for inspection in early March 2015. The entire New Irvington Tunnel Project will be complete in Fall 2015.

1933: Historic photo of  worker at Irvington Portal spherical manifold

Today: New Irvington Tunnel worker at new dishhead at Irvington Portal

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