Identifying Geotechnical Risk and Assigning Ownership on Water and Wastewater Pipeline Projects Using Alternative Project Delivery Methods

Geotechnical and geological risk have the potential to significantly impact the cost and schedule performance of most construction projects. This is especially the case for the design and construction of pipeline systems due to the reliance of these structures on subsurface conditions, typically over long distances. Pipeline projects are often executed using the traditional design-bid-build (DBB) method, but alternative project delivery methods (APDM), such as design-build (DB) and construction manager at risk (CMAR), are becoming increasingly more common. APDM can cause uncertainty regarding the allocation of geotechnical risk on pipeline projects. This uncertainty, coupled with the disparity between traditional and alternative delivery methods, highlights the need for further research into mitigating geotechnical risks on pipeline projects. This paper presents and discusses results from a pilot questionnaire administered to two public water and wastewater pipeline owners to provide an overview of potential geotechnical considerations, risks, and the ways in which risks in these projects are traditionally allocated. The results from these pilot questionnaires show that the owner is allocated a majority of the risk when using each delivery system. However, when using CMAR, the contractor is allocated more risk than when using DBB. Both owners stated that geotechnical risks are allocated differently based on the size of the pipeline and whether it is designed in-house or externally.