New Irvington Water Tunnel
Two Antraquip 175
08 October, 2013: Final breakthrough completes 18,660ft (5.6km) of conventionally mined tunneling on the New Irvington Water Tunnel for the San Francisco Public Utilities Commission. Extensive groundwater inflows extended the excavation timeline by about 12 months and required more than 8.7 million pounds of pre-excavation grouting. The gassy ground classification also proved challenging. Contractor Southland/Tutor Perini now begins installation steel carrier pipe to complete the tunnel. Congratulations are owed to the work crews, engineers, designers, management and support staff on completion of the excavation.