Marine Construction Logistics for a LNG Export Facility

Coal seam gas held deep in the coal in Queensland is a key clean fuel of the future, and the Queensland Curtis LNG project is the first of three major Liquefied Natural Gas (LNG) export facilities to be developed on Curtis Island, near Gladstone, Queensland, Australia. The site is located on Curtis Island, approximately 8 km from Gladstone, which posed complex logistical challenges to support the major construction project. This paper describes the planning and marine infrastructure development with a focus on lessons learned in the design and construction of these facilities, worth over US $200M. As Curtis Island was previously undeveloped, significant marine facilities were required to support the ongoing construction works between 2010 and 2015. Design criteria included a range of vessels and conditions driven by the need for passenger facilities servicing 1,200 site personnel, construction materials delivered by Roll-On Roll-Off (Ro-Ro) vessels, barges carrying aggregate and water and diesel bunkers. For the permanent facilities (also used later in LNG facility construction), the design criteria was expanded to include the material offloading facility (MOF) to accommodate charter shipping and tug/barge combinations bringing in completed process plant modules, fabricated and assembled overseas. Various constraints discussed in this paper defined these facilities. This led to two separate terminals on the mainland, one for aggregate barging and one for passenger vessels and Ro-Ro cargo vessels. Two separate facilities were also developed on Curtis Island. These were: (1) the Construction Dock, built within the first 9 months of project development; and (2) the MOF, designed and built to handle module shipping, charter shipping, passenger vessels, and to also function as the terminal for the support of permanent LNG plant operations. A key factor is that these four facilities operate in a range of conditions from relatively mild currents and wave exposure at Curtis Island, to significant currents at the mainland. During the development process, all of the lessons learned have flowed through each facility, culminating in the optimized design and construction of the LNG Jetty export terminal.