SFPUC Hetch-Hetchy Mountain Tunnel

Project Location


Project Dates

2016 -2017

Services Provided

Construction Management


Hetch-Hetchy Mountain Tunnel scope of work for this project includes improvements to the SFPUC Hetch-Hetchy Mountain Tunnel at Adit 5/6, Adit 8/9, Big Creek Shaft, and Second Garrote Shaft. Improvements at Adits 5/6 and 8/9 to include improvements to access roads, demolition of existing concrete structures near adit entrances, removal of adit access gates and inner steel doors, rock excavation for new bulkheads, construction of new tunnel bulkheads, contact grouting, pressure grouting, construction of adit access gates, demolition of existing bulkhead, removal of tunnel lining, installation of rock bolts, shotcrete lining of tunnel, placement of new adit invert slab, installation of tunnel instrumentation and control panel. Improvements at Big Creek Shaft and Second Garrote Shaft include installation of new conduit, placement of new control panels and equipment, connections from existing power feed to new equipment, installation of casing vertically in the shaft, mounting of pipe in the tunnel, installation of sampling pump in the casing, installation of pressure probe in the casing, testing and startup of instrumentation.