Assessments of Two Major DBO Projects Part Way into Their Operations Phases and Consideration of Enhancements to the DBO Contracting Model

摘要

Seattle Public Utilities' Cedar Treatment Facility and San Diego County Water Authority's TwinOaks Valley Water Treatment Plant have both been delivered using a Design-Build-Operatecontracting approach. The Cedar and Twin Oaks projects went into operations in 2004 and 2008,respectively. Owners using this approach typically believe that by allowing a DBO contractor toinnovate in the combined design, permitting, construction, and operations by customizing thedesign and construction of the facility to achieve its unique performance requirements and waterquality expectations, the designer-builder-operator will maximize efficiency, resulting in lowerconstruction and long term operations costs, and improved schedule and reliability. This paperwill review each project's initial objectives and assess results to date to determine whetherdesired outcomes have been achieved. While every DBO project is different, there tend to besimilar reasons for owners to select a DBO model, and at a high level, similar risk allocationsamong projects. The Cedar DBO project was modeled after Seattle Public Utilities (SPU) ToltTreatment Facility DBO project, which began operations three years prior to the Cedar DBOproject. Many aspects of the Twin Oaks Project were modeled after the Tolt and Cedar DBOprojects. Each of these projects has been the subject of industry observers interested inunderstanding whether the DBO model can consistently deliver results equal to or superior toconventional public works contracting or other alternative contracting approaches. Lessons havebeen learned, and in general, improvements have been made in each subsequent implementationof these DBO models, and those closely involved in the projects discussed in this paper canconceive of further evolution of the model - public-private partnerships for which risks andincentives are optimally placed in all phases of the projects. While this is the intent for any DBOproject, we find that the further we get into the long term operations and maintenance phase, themore likely that the contracts can be further improved based on the unique challenges of theoperations and maintenance phase.