Lessons Learned in the Planning, Design, and Construction of the Carlsbad Desalination Conveyance Pipeline

San Diego County Water Authority (SDCWA), like most of California, is in desperate need for new reliable water supplies. In 2012, SDCWA signed a long-term purchase agreement for water from the Carlsbad seawater desalination plant (desalination plant). The 54 million gallon per day (MGD) desalination plant is the largest desalination plant in the Western Hemisphere. In order to move this new 54 MGD supply into the SDCWA system the Carlsbad desalination conveyance pipeline (conveyance pipeline) and several other improvements to the agency’s system were required. This paper provides details on how SDCWA worked with the private developer, Poseidon Water and the design-builder, Kiewit Shea Desalination Joint Venture to build a new 10 mile, 54-inch pipeline, at a cost of $150 million, that would convey water from a new water supply source, the Pacific Ocean. A complex water purchase agreement and design-build/engineering procurement contract were used to construct the desalination plant. The conveyance pipeline was required to be designed to SDCWA standards and meet all regulatory requirements. The authors from the engineer of record for the project have provided their opinions on both the project successes and the lessons learned on the project. Most importantly the authors described how all parties worked together to deliver this very important regional project.