New Irvington Tunnel Project
Sunol
AWARD OF MERIT
老板San Francisco Public Utilities Commission
Lead DesignerAECOM
ContractorSouthland Tutor Perini JV
Construction ManagementHatch Mott MacDonald
ConsultantJacobs Associates
Subcontractors Johnson Western Gunite Co.; Malcolm Drilling Co.; Municon Consultants; R&W Concrete Contractors; San Joaquin Electric; Pacific International Grout Co.
As a vital part of San Francisco’s Hetch Hetchy Regional Water System, the 1930s-era Irvington Tunnel supplies approximately 85% of the city’s water. However, the critically important tunnel had not been dewatered or physically inspected since 1966. As part of the $4.6-billion Water System Improvement Program, San Francisco built a new 3.5-mile-long tunnel to parallel the original tunnel as a seismically reliable alternative.
High groundwater inflows, gaseous conditions and two major fault zones made the $259-million project extremely challenging. Many pumps extracted water, and crews injected more than 7.8 million lb of cement before excavation to reduce inflow so the team could construct the 13-plus-ft-dia tunnel. Construction was completed with minimal disruption to the water system or to the local population, according to city officials.
Report Abusive Comment