San Francisco Bay Tunnel progress - TunnelCast

March 01, 2012: Some five months into excavation, the Hitachi Zosen EPBM is more than 4,700ft or 18% into its drive on the 5 mile long water supply tunnel under the San Francisco Bay for the SFPUC. On a January 28, 2011 site visit, crews were navigating a pocket of bad ground that had slowed progress rates dramatically.

Snapshot

San Francisco Bay Tunnel Construction

Paula Wallis reports for TunnelTalk
Location:
San Francisco Bay
Dimensions:
Single bore, about 5 miles (8km) long, under the San Francisco Bay at depths ranging from 75ft to 110ft (22-33m), segmentally lined to 108in (3m) i.d. and finished with steel carrier pipes.
Type:
Water tunnel
Owner:
San Francisco Public Utilities Commission
Contract Value:
$215.3 million
TBMs:
Hitachi Zosen EPBM
Segment production:
Traylor Shea Precast, Stockton
Contractor:
Michels/Jay Dee/Coluccio JV
Designer:
Jacobs Associates
Construction Management:
Jacobs Engineering