Description

This webinar will include lessons learned in working through the proposed PDB process . Lake Conestee Dam is a 130-year-old stone masonry structure with an impounded reservoir mostly filled with sediment. The contained sediment consists of a cap of clean material encapsulating contaminated material, that if released by a dam failure could cause a significant public health risk into the downstream reaches of the Reedy River. The risk to the public was deemed unacceptable and the State of South Carolina secured funding to replace the dam by September 2026 because of the brittle nature of masonry dam potential failure modes. The urgency to complete the project on an expedited schedule and within a fixed budget were prompts for the Lake Conestee Dam Replacement Project, LLC (LCDRP), under the advisement of Kleinschmidt Associates and Cumming Group, to pursue a design-build project delivery method. Through a competitive bid, LCDRP selected Kiewit Infrastructure Company South (Kiewit) to proceed with a progressive design-build project (PDB) with the engineering design performed entirely in house. The PDB approach deviated from the traditional design-bid-build (DBB) approach by providing a framework for the design and construction teams to work together from early stages of design and is expected to achieve a cost-effective design that will accelerate the completion months ahead of the stated goal. To achieve these efficiencies, the team also plans to utilize the PDB approach to complete foundation excavation in advance of finalizing the design of a new RCC dam to optimize its alignment within the limits of LCDRP's property and adjust schedule to align with other similar Kiewit projects to leverage crew experience with constructing RCC dams, neither of which would be possible using a more traditional DBB approach.