Progressive Design Build in Silicon Valley

摘要

The Silicon Valley Clean Water Gravity Pipeline (SVCW) is among the first tunnel projects in the United States to be procured using the Progressive Design Build (PDB) method. Selected by SVCW to provide cost certainty after the 60% design level and to allow greater coordination of the design with operations and maintenance, PDB is being used by SVCW to procure two other major projects-the Front of Plant pump station/headworks facility and the member agency Pump Station Improvements. The three projects are critical to SVCW's Regional Environmental Sewer Conveyance Upgrade (RESCU) program. The PDB process has facilitated a collaborative working relationship between owner, contractor and designer to agree design direction, align scheduling, manage risk and ensure designs incorporate SVCW's RESCU program success factors and contractor means and methods. The flexibility of PDB has allowed early milestones to be achieved during Stage 1, prior to negotiation of the Stage 2 lump sum construction contract. These include placement of the TBM order, 100% design for the precast concrete segmental lining and TBM launch shaft, all of which have significant project schedule impacts. Project successes and challenges of the PDB process are discussed from the Owner, Contractor and Designer perspective.