One of the primary reasons the public sector is interested in using PPPs is to achieve time savings in the total development process through concurrent performance of certain activities whose results are not mutually dependent, efficient use of resources, and related cost savings. PPPs can also expedite the application of advanced technology. Thus, private developers seek to "fast-track" design and construction, proceeding with certain elements of the construction work while design is still ongoing on others, and involving the construction firm in design reviews to avoid delays associated with design defects affecting project construction. Time savings can also lower the cost of the project by avoiding large increases in material costs due to price inflation.
Many of the transit capital projects identified in this report that were delivered through a PPP advanced by a year or more in part as a result of the PPP delivery approach. In one instance the application of a PPP advanced the opening date of a planned extension by several years as a result of funding contributions made by private partners.
Design-build expedited completion of the Hiawatha Corridor LRT project by one year over design-bid build by enabling project design and construction schedules to overlap. Similarly, the Largo Metrorail Extension advanced by an estimated two years due to DB, while the Hudson-Bergen Light Rail project advanced by at least one and possibly two years by using a DBOM delivery approach versus design-bid-build.
Both the highway and LRT portions of Denver's T- REX were delivered 22 months earlier than requested in the sponsoring agencies' request for proposals (RFP). While the RFP required completion by June 2008, the project delivery team proposed completion by September 1, 2006, which was one factor in the team's selection. The team met the schedule, completing LRT construction by September 1, 2006 and highway construction a few days earlier.
The DB consortium completed construction of Portland's MAX Airport Extension nine weeks early, providing Tri-Met additional time for initial testing. More importantly, the funding that Bechtel Enterprises brought to the table advanced the project by several years compared to the likely project timeframe if it were required to wait its turn for funding from the region and the Federal government. In fact, the lack of New Starts funding was an added attraction of the PPP as it eliminated the extensive application process required to secure Federal transit capital funds.
The BART Oakland Airport Connector project would not be possible without using a PPP structure because, due to the economic climate, a significant amount of anticipated state funding for the project would not likely have been made available for several years. Using a PPP, this project is moving forward with revenue service scheduled to begin as early as 2011.