5.7 km-long x 2.9 m horseshoe-section Claremont tunnel constructed in 1928 to be emptied and inspected in January, 2001 with a view to designing a seismic improvement programme through the actively creeping portion of the Hayward Fault zone. Project leader Jacobs Associates with Camp, Dresser & McKee, Geomatrix, and Earthquake & Structure Inc. Visit www.jacobssf.com July 2000.The San Francisco Public Utilities Commission (SFPUC) selected URS and Jacobs Associates to design the new Irvington tunnel. The 24-month design phase began in August 2006, and the project construction should reach completion in 2013. The existing Irvington tunnel connects the Alameda siphons in the Sunol Valley to the Bay Division Pipelines in Fremont. This 3 m-diameter tunnel runs approximately 5.6 kilometres between two active faults, the Hayward and Calaveras. Approximately 85% of SFPUC water would not reach the San Francisco Bay Area if the current Irvington tunnel ever failed due to an earthquake or other reasons. Built around 1930, it last saw an inspection in 1966. The SFPUC cannot take it out of service without impacting the water supply. The new Irvington tunnel, of a similar size and length, will lie just south of the existing tunnel. Facilities include the new tunnel with initial and final linings, overflow shaft, tunnel portals, and related ancillary appurtenances. The project, estimated to cost approximately USD120 million, likely will use TBM as the preferred excavation method, and a precast concrete segmental lining system. Visit www.urscorp.com, www.jacobssf.com and www.sfwater.org 09/07.