M-DWASD Design-Build Procurement for Government Cut Pipeline Replacement Project

摘要

Miami-Dade Water and Sewer Department (M-DWASD) is using design-build delivery for a project involving replacement of utility pipelines under Biscayne Bay; a 54-in. (1370-mm) force main (FM) that extends from Miami Beach to Virginia Key, and a 20-in. (510-mm) water main (WM) that extends between Port Island and Fisher Island. The project, referred to locally as the "Government Cut Project", is driven by an aggressive schedule to complete as of October 2012. The schedule must accommodate planned dredging activities to deepen and widen the harbor channels for the Port of Miami to serve the larger Post Panamax ships coming through the Panama Canal in 2014.Trenchless technology methods are being used to replace the pipelines through extremely pervious limestone, constituting some of the most challenging geologic conditions in the United States. To achieve project objectives, a significant site and subsurface investigation was necessary in addition to very complex permitting efforts. Land / ROW acquisition and easements were also required to obtain site areas for work activities as well as the permanent installations. The procurement process was a two-step "best value" procurement approach that selected the Design-Builder from a shortlist of best-qualified firms on the basis of both technical solution and price. The Request for Proposal promoted innovation through submittal of alternate proposals from the competing D-B firms, at their option, if proposers also submitted a base proposal in full compliance with the Request for Proposal (RFP).This paper will describe the nature of required design and construction, including the procurement process that M-DWASD used to address the challenges and risks faced by the project. A brief summary of the technical solution being implemented by the Design-Builder is provided. Further details regarding the design and construction methods are covered in a paper by the authors in the 2012 North American Tunnel Conference proceedings (Dill et al, 2012).